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Converting my Amel 54 to lithium batteries: what I did, what I like and what I don't like (after one year of full time live aboard use)

Scott SV Tengah
 
Edited

A little over a year ago, I replaced my nearly stock Amel 54 “comfort package” lead acid system with a nearly complete LifePo4, aka lithium battery system. The system was designed with the help of Victron engineers and of course a marine electrician, but I will say that many marine electricians today try to apply lead acid thinking to lithium and it leads to many unintended consequences. I promised many of you a writeup on my 1 year experience with my system, what works and what could be better.

I’ll start by saying that lithium truly is life changing. All of the 230v appliances we ran earlier, we can run without genset. On battery, we can cook with induction, run aft aircon all night, heat water, run the boiler, wash clothes and dishes and moreover, charging just got a 20-25% boost due to lithium’s charging efficiency. The only thing that won’t run is that I can’t start up the scuba compressor on inverter power, probably due to startup spike. I can probably install a capacitor to fix that, but it’s low priority and I’m fine starting the genset for that. Despite the cost of my system, I would do it again in a heartbeat. It is the best change we have made on the boat, without question.

I’ll also preface by saying what I’ve said many a time before - I am not an engineer by any means but I simply research, ask questions, execute and then test extensively. I rely on people smarter than me to advise me on things I don’t understand, of which there are many. It’s not a cheap system but given that we are at the front end of a multi-year circumnavigation, I believe the amortized cost is lower than using flooded lead acid/gel/agm. That is, if you don’t kill the batteries, which an improperly setup system may very well do.

My old system consisted of the following:

  • Twelve 100AH 12v gel batteries, wired in serial pairs to make 24v and then wired in parallel to make 600 amp hours.
  • Dolphin 100amp primary and 30amp secondary charger
  • Mastervolt 110amp 24v changer on the main engine with Alpha Pro 1 regulator
  • Xantrex power monitor

I’ll start by listing the components of my current electrical system, specifically items related to my lithium installation:

  • Six Victron Smart lithium 150ah 12.8v batteries, wired in serial pairs to make 25.6v and then wired in parallel to make 450AH.
  • Victron VE.BUS BMS
  • Victron Quattro 24v/5000va/120amp charger/inverter
  • Victron Skylla-i 24/80 (3) charger with correct adaptor to allow it to talk to the VE.BUS BMS
  • Mastervolt 110amp 24v changer on the main engine with Alpha Pro 2 regulator
  • Three LG Neon2 320watt solar panels for a total of 960w wired in parallel
  • Victron BlueSolar 150/35 MPPT charger with the correct adaptor to allow it to talk to the VE.BUS BMS
  • Victron BMV-712 battery monitor

Let’s walk through the individual components and why I chose them, what I like about them and what could be better. The system is NOT perfect and some of the problems I’m trying to solve for are still outstanding. Part of this writeup is to ask for your help, especially those of you who studied/worked with this stuff, and to explain my decision making and have you tell me, with a reasoned argument and evidence, why a different way is better. Or provide solutions for holes in my system - I’ll be the first to say that they exist.

You will note heavy representation by one brand - Victron. That was intentional because one of my biggest fears is that the batteries die and if I had lots of different brands for the various components, they will each point fingers at the other and I would be left holding the bag. Victron has a great reputation and my experience with them has been great. I’m sure Mastervolt or Battle Born or XXXXYYY brand is great, so don’t take my component selection as saying that Victron is the best and no other brand will work. 

Batteries: We’ll start with the battery selection. Because lithium can easily go 2000 cycles even with 80% DOD, you don’t need as much bank capacity to equal usable capacity compared to lead acid. With my original 600AH setup and no more than the recommended 40% DOD, the usable AH is 600*.4=240AH. Given the batteries are 12.8v, you need an even number of them to make 25.6v, so I could have gone with 4 of them and had the same usable capacity (300*.8 = 240AH) as the original 600AH setup. But I went for 6 batteries and got 450AH and (450*.8=360AH) usable capacity. Sure, even more is nice, but the reality is that my solar array only puts out about 200-250AH a day, so additional battery bank capacity would simply extend the interval for running the generator and 230v chargers. I probably won’t install a wind generator for various reasons. Each pair of batteries is connected serially using copper bars. The Electrican tried battery cables as jumper wires (“but this worked fine on every other <lead acid> setup I’ve installed!”) but the current going through them caused the cables to overheat. The copper bars aren’t perfect because they can exert force on the battery posts, but that’s the best solution I’ve found to date. Note that each pair is wired to the Amel installed +ve and -ve post in the battery compartment using equal length battery cables.

The Victron Smart lithium 150AH batteries fit in the stock battery location under the passage berth. They were nearly the perfect size, only requiring me to trim a bit of the wooden bracing under the “lid” of the passage berth bed. Some may put larger batteries horizontally, but Victron explicitly cautions against that. For warranty reasons, I will follow their advice. The batteries are considerably lighter than my previous gel batteries - I lost 258kg in battery weight alone. That’s actually a bit of a problem because now we list about 1-1.5 degrees to port and my port side gelcoat is under the waterline and requires weekly scrubbing! Nearly half the battery compartment is empty but I’m too afraid to put anything in the same location as those expensive batteries. 

I also added 3 fuses, 450 amps each. 

My understanding is that Amel didn’t install battery bank fuses because they didn’t want you to lose bow thruster, windlass or other critical high draw components when voltage drops and consequently amperage skyrockets. This is not really a concern with lithium, where the voltage drop is negligible even when I draw 200amps from them. I can easily run the bow thruster or the windlass with engine/genset off. Even to my non-engineer mind, having non-fused big batteries like this just sounds dangerous. Hearing about a few Amel battery bank explosions reinforces my fear, so I went for the fuses. I zip tie backup fuses and also jumper wires nearby in case the installed fuses fail to handle the currents Amel 54s require. No problems so far.

BMS: With Victron, I went for the VE.BUS BMS system. All the pigtails from the six batteries run in serial to the BMS. As you may know, the BMS monitors the battery condition, down to the cell level.

230v Charger/Inverter: I chose the Quattro 24/5000/120 because it barely fit into the spot where the old Dolphin 100A charger sat, in the engine room. This gives me 5000va (watts, more or less, depending on the 230v appliance) of inverter capacity and can charge at up to 120amps. With lithium, the batteries can take nearly the full charging current up until high 90s state of charge, so I opted for lots of charging capacity for shorter genset runtime. We aren’t on shore power much, so I can’t comment except to say that much of the time, your shore power connection can’t handle that much amperage, so you’ll be limited by that.

The inverter capacity allows us to run virtually everything on the boat. The admiral has been known to run the toaster, microwave and induction cooker at the same time. While the batteries can easily handle that in terms of current delivery, if you draw 200amps like that, you’ll drain the battery bank in about 2.5 hours. Note that lithium capacity does not drop dramatically like lead acid with increasing current.  For lead acid, when they say 100amp hours, they mean 5 amps an hour for 20 hours (test load=capacity/20hrs). If you draw 100amps on a lead acid battery, it will probably last 10 minutes and result in a massive voltage drop, increasing your amperage even more. That is not the case with lithium. 

Why did I choose the 5000va Quattro and not 3000va model or the 8000va model? 

Well for the 3000va model, I figured there would be times where the admiral or crew overload the inverter. It’s not the end of the world if you have a 3000va inverter, but since the batteries can easily handle 5000va of draw, I figured why not? Also the ratings are made for operation at 25 degrees Celsius. It might get a bit hotter on my boat so I wanted excess capacity. Additionally the 5000va fits perfectly, (correction: vertically as Victron intended), where the old Dolphin 100amp charger fit. We had to add a wood board for backing, but it fits perfectly and takes advantage of the ventilation provided by Amel to the original Dolphin 100amp. After a year of usage, I have never noted output nor charging current reduction due to heat. The 8000va model is larger and heavier and I am not sure it will fit in the stock Dolphin 100 location. Additionally, the standby draw is twice (2 amps+) the standby draw of the 5000va. There is some power save mode but that makes my analog Amel voltmeter jump constantly, which I avoided for longevity reasons. For me, the Quattro 24/5000/120 was the goldilocks solution.

By using the Quattro, you take the original Amel 230v automatic switch out of the system as the Quattro does it internally. There are advantages to that, as you will see later.

Installing the Quattro requires an ethernet cable and FOUR 50mm^2 battery cables from the engine room to the battery compartment. That means you need to break the epoxy seal between the engine compartment and the passage berth, located on the floor on the forward end of the “passage”. After this, you will re-epoxy the hole so the watertight separation is re-established. I also ran an additional ethernet cable in case of failure of the original cable.

I also added a Victron Skylla-i 24/80 charger. This is intentional for two reasons: (1) If the main Quattro fails, I can easily rewire the shore power lead and run the Skylla. This duplicates the redundancy we had with the original Dolphin 100amp / 30 amp separate chargers. (2) Additionally, this gives me a way to plug-in at marinas that are primarily 110v and then double them up to produce 220v. This is common in the Americas. The problem with this system is that it still retains 60hz, but many of the appliances in our 54 do not run on 60hz. So the concept is that we can use the Skylla to charge the lithium batteries and have the Quattro provide 230v/50hz power via the inverter.  The Skylla is wired using the old cables that were connected to the Dolphin 100amp charger. If Amel believes the cables can handle 100amps, I presume it can handle 80amps. The Skylla fits where the old Dolphin 30 amp charger fit, right next to the Quattro.

When the Quattro detects mains/genset power, it will immediately pass it through to the boat’s internal 230v wiring. If that shore power is 60hz, you have a problem. I specifically asked Victron if I could force the Quattro to just charge and not pass through shore power and the answer was a definitive NO. So the Skylla solves that problem if the situation ever arises where we need to plug in for longer periods in locations that only provide 60hz power. I’m sure an expensive frequency converter would be more seamless, but we don’t anticipate many if any long periods of plugging in in the Americas.

Alternator and Charge Controller: The original Mastervolt Alpha Pro 1 alternator charge controller does not have a lithium charging profile and had to be replaced with a newer model. Unfortunately Victron does not make alternators nor alternator charge controllers. Note that most alternators will burn up when subjected to the charging loads imposed by lithium. With lead acid, the maximum current is only required for a short period as lead acid cannot accept full charging current once you get above say 60% state of charge. So your typical 100 amp alternator will only be required to output 100amps for a short period. With lithium, it will be required to output the full amperage until the battery bank is nearly full. Many alternators cannot handle the heat generated from this and will burn out quickly. Speaking to Mastervolt engineers, they were adamant that the Mastervolt 24/110 can easily handle outputting the full current for long periods as lithium requires. For extra measure, I installed a temperature sensor on the alternator to reduce output if the alternator overheats. Additionally, I limited maximum output to 90 amps. This is done via an ethernet adaptor from Mastervolt.

Renewable power generation: I installed a stainless arch above my davits and mounted LG Neon2 panels. I wanted the 350w model but they only had 320w in stock. Note that the size is exactly the same, it’s just some panels have higher yield than others. This gives me 960w total. I opted to connect them in parallel, which requires thicker cables (13mm2) and more of them, but given my research, I believe parallel will allow higher daily total output when there is partial shading from sails/masts. Electricians often push for serial wiring as it’s easier. The solution we came up with is to have a pair of wires from each panel to a junction/switch in the lazarette and then a single pair from there to the MPPT charge controller.

For charge controlling, I opted for the Victron BlueSolar 150/35 MPPT controller. The 150v gives me the voltage capacity in case I decide to re-wire the panels to serial and the 35 amps is just at the level recommended for 1000 watts of solar.

The electricians installed it in the same passage berth compartment as the main switches, which after a while, I realized was not ideal. More about that later.

Finally, I installed a Victron BMV-712 battery monitor in the same location as the original Xantrex monitor, on the Amel 24v panel. It fit perfectly.

Operation:

Lithium thinking is very different from conventional lead acid thinking. The batteries do not like to be kept at 100%, in fact, for optimal lifetime, you should keep them at 40-50% state of charge. I generally try to keep them between 40-80%. The renewables will add on average, 200-250 amp hours a day in tropical areas. That almost covers my daily usage. But energy is like money, you will never have enough and if you’re not careful, you will end up using more than you have!

With lithium, you can think of the batteries as a “gas tank” for energy. After a year’s usage, the amount I put in via charging is only 2.5% less than the amount drawn out. That 2.5% is charging inefficiency. With lead acid, the charging inefficiency/loss around 10x as much, so when you draw 20 amps, you need to put in 25 amps to replace it! That means the same 1000 watt solar array with lithium is effectively a 750watt array with lead acid. And given that lithium can accept full charge current up to high 90s SOC, very little generated solar power is "wasted" by batteries not being able to accept full current at high SOC, a common problem with lead acid. With the thousands of cycles available in lithium and the charging efficiency, my primary concern is keeping the batteries between 40-80%. 

Right now, every 3 days, on overage, I’ll start up the genset and run both chargers (200amp total) for around 30 minutes. My procedure is that I’ll turn off all the chargers (not simple on the Quattro as you need to login via the MK3-USB connector and use the VE-Config software and reduce charging current to zero amps. Then I’ll start the Onan 11kw and run it for 30 seconds before turning on all the chargers to allow oil to circulate. The Skylla 80 amp is wired into the original 230v panel switch for the 100amp Dolphin. I haven’t gotten around to changing the label yet. :) I wire that to AC output 2 on the Quattro, so the Skylla only runs on shorepower/genset, rather than inverter. It also delays switching on by 2 minutes, I believe. Everything else is wired to run off the inverter. Yes, even the water heater and aircon.

To turn off the genset, I’ll turn off all the chargers and then let the genset run with no load for 1 minute before shutting it down. This cool down procedure is probably overkill, but specifically recommended by Onan. Then I’ll reset the Quattro to max charging power in case the laptop dies and I’m unable to increase it later. This procedure, while it occurs only twice a week or so, is something I’m trying to eliminate. I’ll talk about that later.

One disadvantage of pairing up the batteries to produce the required 24v is that these serial pairs can become imbalanced. Same with lead acid, so nothing new here. Most people just let it be, but I am a bit more careful. Once a year or whenever I have good shore power, I’ll use the Quattro to fully charge the battery bank and then disconnect all the batteries. If I’m still living aboard, the Skylla provides clean enough output that I can use it to provide 24v in the absence of a battery bank. I will take my small 12.8v lithium specific charger (1.5amps), which you can buy for $30 on Amazon and charge each 12.8v battery individually. By topping them off individually in this manner, when I pair them back up, they are re-balanced. The Victron batteries have balancing capabilities within the cells of each individual battery, but NOT across a serial pair. While this is probably not necessary, the cost of the batteries is making me do whatever I can do ensure they are happy. I went nearly a year before this balancing procedure and the batteries remained quite balanced - again my procedure is probably overkill.

Problems/Holes:

All is not perfect on our system. With lithium, each 12.8v battery is composed of 4cells. If any of those cells drop below a certain voltage or go above a certain voltage or overheat, they will be damaged irreparably. That’s why you have a BMS to monitor all the cells individually. However, the BMS only warns of dangerous conditions - you need something to act on that warning.

Battery Disconnect: 

You need a device to disconnect loads when the voltage is low, as indicated by the BMS. Initially I installed the Victron BP-220 which can handle 220 amps continuous and a lot more for short periods, supposedly. It was a reminder never to trust the marketing material without testing. The first time I used my hydraulic passarelle, the BP-220 melted. The Amel was not initially wired with lithium in mind, so the “control” wires that are connected to switches and have low current are not separated from the “power supply” wires when they get to the main switches. If you could take the time to separate that out, 220 amp capacity of the BP-220 would be plenty, but as is, it’s not sufficient. 

My current solution involves not letting the battery bank state of charge drop below 25%. I’ve confirmed with Victron that this will make it very very unlikely that you’ll have a cell low voltage condition.  Moreover, the inverter will stop inverting if the BMS indicates a cell low voltage condition.

Does anyone have a solenoid they can suggest? The VE.BUS BMS load disconnect functions by sending out a signal at battery voltage (eg - 25.8v) when all is good and drops to open circuit when the load needs to be disconnected. The VE.BUS BMS can power a solenoid that requires up to 2amps but obviously I would prefer something that is bi-stable so it doesn’t draw power continuously when all is good. I would prefer something that can handle at least 600amps continuous.

Charging Disconnect:

To prevent cell over temperature or over voltage, there needs to be a way to cut off charging. The VE.BUS BMS communicates with the Quattro, the Skylla and the MPPT. If the BMS signals a problem, the Victron devices will stop charging.

The Mastervolt alternator, however, is not controlled by the VE.BUS BMS. According to Victron documentation, the VE.BUS BMS has an output that provides 10mA of power to control a simple relay in response to battery over voltage conditions. The Mastervolt controller has a “reg-on” brown wire that allows you to safely cut off charging on the Mastervolt alternator. All you need to do is disconnect it. Mastervolt provides this functionality and states that you can wire it to a switch and use it to safely turn off the alternator to give additional motoring power when needed. So it’s safe for the alternator, per Mastervolt. But, despite trying 24v relays and even 12v relays, the VE.BUS BMS could not power a relay to control the reg-on and consequently turn off the alternator if necessary. 

I had a long discussion with Victron engineers and they suggested I try this very low current relay. 

https://www.schneider-electric.com/en/product/RSL1PREU/interface-plug-in-relay---zelio-rsl---1-c-o---48-v-dc---6-a---with-led/

Any thoughts on this? It needs to require a lower power draw to activate than a normal 24 or 12v Hella automotive relay.

In the meantime, the Victron engineers suggested I set the absorption voltage on the Mastervolt to 27.5 volts. By doing that, it does not fully charge the lithium bank and with that low of absorption voltage, the likelihood we have a cell overvoltage condition is very very small. In fact, given lithium’s distaste of persistent high state of charge, I may lower the absorption voltage further so I don’t keep the batteries at high SOC during extended motoring.

Shorepower charging and state of charge:

Another problem I have tried to solve is regarding state of charge while plugged in for long periods. Personally I don’t like to plug in because of horror stories I’ve heard regarding bad wiring at marinas and zincs disappearing very quickly. In fact, I’ve been tied up for 2 months during this hurricane season and I have not even bothered to plug in - I just let the solar array take care of the batteries.  We even run AC when it’s too hot.

Now the challenge when you’re either plugged in or not using much energy as is the case when you’re not moving much is how to keep the batteries from sitting at 100%. Lead acid thinking requires you to keep the batteries fully charged - in the lithium world that will reduce their lifespan. 

One solution is to set a lower absorption voltage when you’re plugged into shore power for a long time, so that the chargers stop charging at say, 60% state of charge. This is done through trial and error because one of the advantages of lithium is very little voltage drop with respect to state of charge. That, of course, makes it hard to determine state of charge. But trial enough or more accurately, error enough and you’ll figure it out.

MPPT choice and location:

If I could do it again, I would have bought the SmartSolar vs. the BlueSolar. I like monitoring and tracking and the SmartSolar has the bluetooth transmitter built in. The BlueSolar does not and requires that I add in a bluetooth transmitter, which is fine except for the fact that the same data comm port on the MPPT is used by the charging cutoff signal from the VE.BUS BMS. 

I also don’t like the current location of the BlueSolar MPPT as it heats up the main battery switch compartment where it’s located. I don’t want to vent it to the passage berth area as we don't want to add more heat to our living spaces. I also don’t want to vent it outside using the existing battery vent because I would rather not have salt mist enter a compartment full of wires. I’m sure Amel thought of that when they installed the vent in the engine room - I am not going to take unnecessary risk with my expensive lithium setup by altering the vent system in the battery compartment. What I will likely do is mount it in the engine room and use the old wiring for the Dolphin 30 amp charger to extend the solar panel feed to the MPPT. Then I’ll just use the same 2 pairs of 50mm2 wires that the Quattro uses in order to feed solar charging current to the batteries. 

Safety, Better Batteries, Drop In Solutions, Replacing Batteries.

A few final notes - LifePo4 is very different and far safer than the lithium batteries that you hear about blowing up in phones and laptops. You can research it, so I’ll leave it at that. Some have suggested that cheaper and better battery technologies are right around the corner. To me, I could wait until next year to buy a computer and I might get a faster one, but then I will not have a computer for a year. We are circumnavigating now and really enjoy having a functioning power system now. After experiencing life on lithium, I would never go back to lead acid/gel/agm. Moreover, I knew some people when I was back in grad school (known for their engineering department) who were talking about solid state batteries and that wasn’t last year. :) The statements I’ve read about solid state batteries being right around the corner have been from the same institution. Perhaps this time, it’s true, but I am not holding my breath.

Some companies are selling you drop in solutions. Just buy their lithium batteries and you can use your existing charging system and it just works. Hopefully after reading this description of my experience with lithium, you will not send money to them. Otherwise you’ll probably be sending more money once your batteries die unexpectedly.

Finally, some have wondered what happens if a battery fails in the middle of the Tuomotus, stating that you can’t find a lithium replacement out there and you’re screwed. Well, while I agree you won’t find a lithium replacement in every harbor in the world, you aren’t really screwed. All of my chargers can handle standard gel/lead acid/agm batteries and if necessary, you can replace them with lead acid and just change the charging profile. But the reality is that with the ability for lithium to take deep discharges with no damage, I would probably just take a battery pair out of my bank and keep going. But this does highlight the fact that you should be able to change the charging profile yourself. It’s not rocket science and if I can do it, anyone can.

Next steps for me:

As I mentioned, I am not 100% happy with the alternator charge (high voltage) disconnect situation and the missing low voltage load disconnect solution. I’m all ears on how I can fix those.

The next project for me, which could be easy or cause intense brain damage is wiring the Onan generator to automatically start at 30% SOC and turn off at 75% SOC. It’s relatively easy to get the Onan generator to start with the Victron system, but I want the generator to start, with no load for 30 seconds, then turn on the chargers, run for the necessary time to charge up to 75% SOC and then turn off chargers and run the generator for an additional 60 seconds to cool down before shutting off the generator. 

I think I’ve found a solution in the programmable relays in the Quattro paired with the relay in the BMV-712, but I need to consult with my smart friends first before I try this solution. With it implemented, my system would remove one of the heretofore seemingly unavoidable annoyances of sailing an electricity hungry sailboat - constantly monitoring the battery SOC. The solar would provide most of my power and if that proves not enough, the generator would automatically kick in, maintaining the built in protections (overheat/oil pressure/etc) that the Onan has.

Anyways, this post is far too long already. Hopefully this opens up a discussion and I’m happy to answer any questions on things that I have not explained clearly or omitted, which I’m sure there are many.

-- 

Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Matt Salatino
 

Excellent discussion. Very informative and educational.
Thanks!

~~~⛵️~~~Matt

On Sep 3, 2019, at 9:03 AM, Scott SV Tengah <Scott.nguyen@...> wrote:

[Edited Message Follows]
[Reason: Formatting]

A little over a year ago, I replaced my nearly stock Amel 54 “comfort package” lead acid system with a nearly complete LifePo4, aka lithium battery system. The system was designed with the help of Victron engineers and of course a marine electrician, but I will say that many marine electricians today try to apply lead acid thinking to lithium and it leads to many unintended consequences. I promised many of you a writeup on my 1 year experience with my system, what works and what could be better.

I’ll start by saying that lithium truly is life changing. All of the 230v appliances we ran earlier, we can run without genset. On battery, we can cook with induction, run aft aircon all night, heat water, run the boiler, wash clothes and dishes and moreover, charging just got a 20-25% boost due to lithium’s charging efficiency. The only thing that won’t run is that I can’t start up the scuba compressor on inverter power, probably due to startup spike. I can probably install a capacitor to fix that, but it’s low priority and I’m fine starting the genset for that. Despite the cost of my system, I would do it again in a heartbeat. It is the best change we have made on the boat, without question.

I’ll also preface by saying what I’ve said many a time before - I am not an engineer by any means but I simply research, ask questions, execute and then test extensively. I rely on people smarter than me to advise me on things I don’t understand, of which there are many. It’s not a cheap system but given that we are at the front end of a multi-year circumnavigation, I believe the amortized cost is lower than using flooded lead acid/gel/agm. That is, if you don’t kill the batteries, which an improperly setup system may very well do.

My old system consisted of the following:

  • Twelve 100AH 12v gel batteries, wired in serial pairs to make 24v and then wired in parallel to make 600 amp hours.
  • Dolphin 100amp primary and 30amp secondary charger
  • Mastervolt 110amp 24v changer on the main engine with Alpha Pro 1 regulator
  • Xantrex power monitor

I’ll start by listing the components of my current electrical system, specifically items related to my lithium installation:

  • Six Victron Smart lithium 150ah 12.8v batteries, wired in serial pairs to make 25.6v and then wired in parallel to make 450AH.
  • Victron VE.BUS BMS
  • Victron Quattro 24v/5000va/120amp charger/inverter
  • Victron Skylla-i 24/80 (3) charger with correct adaptor to allow it to talk to the VE.BUS BMS
  • Mastervolt 110amp 24v changer on the main engine with Alpha Pro 2 regulator
  • Three LG Neon2 320watt solar panels for a total of 960w wired in parallel
  • Victron BlueSolar 150/35 MPPT charger with the correct adaptor to allow it to talk to the VE.BUS BMS
  • Victron BMV-712 battery monitor

Let’s walk through the individual components and why I chose them, what I like about them and what could be better. The system is NOT perfect and some of the problems I’m trying to solve for are still outstanding. Part of this writeup is to ask for your help, especially those of you who studied/worked with this stuff, and to explain my decision making and have you tell me, with a reasoned argument and evidence, why a different way is better. Or provide solutions for holes in my system - I’ll be the first to say that they exist.

You will note heavy representation by one brand - Victron. That was intentional because one of my biggest fears is that the batteries die and if I had lots of different brands for the various components, they will each point fingers at the other and I would be left holding the bag. Victron has a great reputation and my experience with them has been great. I’m sure Mastervolt or Battle Born or XXXXYYY brand is great, so don’t take my component selection as saying that Victron is the best and no other brand will work. 

Batteries: We’ll start with the battery selection. Because lithium can easily go 2000 cycles even with 80% DOD, you don’t need as much bank capacity to equal usable capacity compared to lead acid. With my original 600AH setup and no more than the recommended 40% DOD, the usable AH is 600*.4=240AH. Given the batteries are 12.8v, you need an even number of them to make 25.6v, so I could have gone with 4 of them and had the same usable capacity (300*.8 = 240AH) as the original 600AH setup. But I went for 6 batteries and got 450AH and (450*.8=360AH) usable capacity. Sure, even more is nice, but the reality is that my solar array only puts out about 200-250AH a day, so additional battery bank capacity would simply extend the interval for running the generator and 230v chargers. I probably won’t install a wind generator for various reasons. Each pair of batteries is connected serially using copper bars. The Electrican tried battery cables as jumper wires (“but this worked fine on every other <lead acid> setup I’ve installed!”) but the current going through them caused the cables to overheat. The copper bars aren’t perfect because they can exert force on the battery posts, but that’s the best solution I’ve found to date. Note that each pair is wired to the Amel installed +ve and -ve post in the battery compartment using equal length battery cables.

The Victron Smart lithium 150AH batteries fit in the stock battery location under the passage berth. They were nearly the perfect size, only requiring me to trim a bit of the wooden bracing under the “lid” of the passage berth bed. Some may put larger batteries horizontally, but Victron explicitly cautions against that. For warranty reasons, I will follow their advice. The batteries are considerably lighter than my previous gel batteries - I lost 258kg in battery weight alone. That’s actually a bit of a problem because now we list about 1-1.5 degrees to port and my port side gelcoat is under the waterline and requires weekly scrubbing! Nearly half the battery compartment is empty but I’m too afraid to put anything in the same location as those expensive batteries. 

I also added 3 fuses, 450 amps each. 

My understanding is that Amel didn’t install battery bank fuses because they didn’t want you to lose bow thruster, windlass or other critical high draw components when voltage drops and consequently amperage skyrockets. This is not really a concern with lithium, where the voltage drop is negligible even when I draw 200amps from them. I can easily run the bow thruster or the windlass with engine/genset off. Even to my non-engineer mind, having non-fused big batteries like this just sounds dangerous. Hearing about a few Amel battery bank explosions reinforces my fear, so I went for the fuses. I zip tie backup fuses and also jumper wires nearby in case the installed fuses fail to handle the currents Amel 54s require. No problems so far.

BMS: With Victron, I went for the VE.BUS BMS system. All the pigtails from the six batteries run in serial to the BMS. As you may know, the BMS monitors the battery condition, down to the cell level.

230v Charger/Inverter: I chose the Quattro 24/5000/120 because it barely fit into the spot where the old Dolphin 100A charger sat, in the engine room. This gives me 5000va (watts, more or less, depending on the 230v appliance) of inverter capacity and can charge at up to 120amps. With lithium, the batteries can take nearly the full charging current up until high 90s state of charge, so I opted for lots of charging capacity for shorter genset runtime. We aren’t on shore power much, so I can’t comment except to say that much of the time, your shore power connection can’t handle that much amperage, so you’ll be limited by that.

The inverter capacity allows us to run virtually everything on the boat. The admiral has been known to run the toaster, microwave and induction cooker at the same time. While the batteries can easily handle that in terms of current delivery, if you draw 200amps like that, you’ll drain the battery bank in about 2.5 hours. Note that lithium capacity does not drop dramatically like lead acid with increasing current.  For lead acid, when they say 100amp hours, they mean 5 amps an hour for 20 hours (test load=capacity/20hrs). If you draw 100amps on a lead acid battery, it will probably last 10 minutes and result in a massive voltage drop, increasing your amperage even more. That is not the case with lithium. 

Why did I choose the 5000va Quattro and not 3000va model or the 8000va model? 

Well for the 3000va model, I figured there would be times where the admiral or crew overload the inverter. It’s not the end of the world if you have a 3000va inverter, but since the batteries can easily handle 5000va of draw, I figured why not? Also the ratings are made for operation at 25 degrees Celsius. It might get a bit hotter on my boat so I wanted excess capacity. Additionally the 5000va fits perfectly, albeit sideways, where the old Dolphin 100amp charger fit. We had to add a wood board for backing, but it fits perfectly and takes advantage of the ventilation provided by Amel to the original Dolphin 100amp. After a year of usage, I have never noted output nor charging current reduction due to heat. The 8000va model is larger and heavier and I am not sure it will fit in the stock Dolphin 100 location. Additionally, the standby draw is twice (2 amps+) the standby draw of the 5000va. There is some power save mode but that makes my analog Amel voltmeter jump constantly, which I avoided for longevity reasons. For me, the Quattro 24/5000/120 was the goldilocks solution.

By using the Quattro, you take the original Amel 230v automatic switch out of the system as the Quattro does it internally. There are advantages to that, as you will see later.

Installing the Quattro requires an ethernet cable and FOUR 50mm^2 battery cables from the engine room to the battery compartment. That means you need to break the epoxy seal between the engine compartment and the passage berth, located on the floor on the forward end of the “passage”. After this, you will re-epoxy the hole so the watertight separation is re-established. I also ran an additional ethernet cable in case of failure of the original cable.

I also added a Victron Skylla-i 24/80 charger. This is intentional for two reasons: (1) If the main Quattro fails, I can easily rewire the shore power lead and run the Skylla. This duplicates the redundancy we had with the original Dolphin 100amp / 30 amp separate chargers. (2) Additionally, this gives me a way to plug-in at marinas that are primarily 110v and then double them up to produce 220v. This is common in the Americas. The problem with this system is that it still retains 60hz, but many of the appliances in our 54 do not run on 60hz. So the concept is that we can use the Skylla to charge the lithium batteries and have the Quattro provide 230v/50hz power via the inverter.  The Skylla is wired using the old cables that were connected to the Dolphin 100amp charger. If Amel believes the cables can handle 100amps, I presume it can handle 80amps. The Skylla fits where the old Dolphin 30 amp charger fit, right next to the Quattro.

When the Quattro detects mains/genset power, it will immediately pass it through to the boat’s internal 230v wiring. If that shore power is 60hz, you have a problem. I specifically asked Victron if I could force the Quattro to just charge and not pass through shore power and the answer was a definitive NO. So the Skylla solves that problem if the situation ever arises where we need to plug in for longer periods in locations that only provide 60hz power. I’m sure an expensive frequency converter would be more seamless, but we don’t anticipate many if any long periods of plugging in in the Americas.

Alternator and Charge Controller: The original Mastervolt Alpha Pro 1 alternator charge controller does not have a lithium charging profile and had to be replaced with a newer model. Unfortunately Victron does not make alternators nor alternator charge controllers. Note that most alternators will burn up when subjected to the charging loads imposed by lithium. With lead acid, the maximum current is only required for a short period as lead acid cannot accept full charging current once you get above say 60% state of charge. So your typical 100 amp alternator will only be required to output 100amps for a short period. With lithium, it will be required to output the full amperage until the battery bank is nearly full. Many alternators cannot handle the heat generated from this and will burn out quickly. Speaking to Mastervolt engineers, they were adamant that the Mastervolt 24/110 can easily handle outputting the full current for long periods as lithium requires. For extra measure, I installed a temperature sensor on the alternator to reduce output if the alternator overheats. Additionally, I limited maximum output to 90 amps. This is done via an ethernet adaptor from Mastervolt.

Renewable power generation: I installed a stainless arch above my davits and mounted LG Neon2 panels. I wanted the 350w model but they only had 320w in stock. Note that the size is exactly the same, it’s just some panels have higher yield than others. This gives me 960w total. I opted to connect them in parallel, which requires thicker cables (13mm2) and more of them, but given my research, I believe parallel will allow higher daily total output when there is partial shading from sails/masts. Electricians often push for serial wiring as it’s easier. The solution we came up with is to have a pair of wires from each panel to a junction/switch in the lazarette and then a single pair from there to the MPPT charge controller.

For charge controlling, I opted for the Victron BlueSolar 150/35 MPPT controller. The 150v gives me the voltage capacity in case I decide to re-wire the panels to serial and the 35 amps is just at the level recommended for 1000 watts of solar.

The electricians installed it in the same passage berth compartment as the main switches, which after a while, I realized was not ideal. More about that later.

Finally, I installed a Victron BMV-712 battery monitor in the same location as the original Xantrex monitor, on the Amel 24v panel. It fit perfectly.

Operation:

Lithium thinking is very different from conventional lead acid thinking. The batteries do not like to be kept at 100%, in fact, for optimal lifetime, you should keep them at 40-50% state of charge. I generally try to keep them between 40-80%. The renewables will add on average, 200-250 amp hours a day in tropical areas. That almost covers my daily usage. But energy is like money, you will never have enough and if you’re not careful, you will end up using more than you have!

With lithium, you can think of the batteries as a “gas tank” for energy. After a year’s usage, the amount I put in via charging is only 2.5% less than the amount drawn out. That 2.5% is charging inefficiency. With lead acid, the charging inefficiency/loss around 10x as much, so when you draw 20 amps, you need to put in 25 amps to replace it! That means the same 1000 watt solar array with lithium is effectively a 750watt array with lead acid. And given that lithium can accept full charge current up to high 90s SOC, very little generated solar power is "wasted" by batteries not being able to accept full current at high SOC, a common problem with lead acid. With the thousands of cycles available in lithium and the charging efficiency, my primary concern is keeping the batteries between 40-80%. 

Right now, every 3 days, on overage, I’ll start up the genset and run both chargers (200amp total) for around 30 minutes. My procedure is that I’ll turn off all the chargers (not simple on the Quattro as you need to login via the MK3-USB connector and use the VE-Config software and reduce charging current to zero amps. Then I’ll start the Onan 11kw and run it for 30 seconds before turning on all the chargers to allow oil to circulate. The Skylla 80 amp is wired into the original 230v panel switch for the 100amp Dolphin. I haven’t gotten around to changing the label yet. :) I wire that to AC output 2 on the Quattro, so the Skylla only runs on shorepower/genset, rather than inverter. It also delays switching on by 2 minutes, I believe. Everything else is wired to run off the inverter. Yes, even the water heater and aircon.

To turn off the genset, I’ll turn off all the chargers and then let the genset run with no load for 1 minute before shutting it down. This cool down procedure is probably overkill, but specifically recommended by Onan. Then I’ll reset the Quattro to max charging power in case the laptop dies and I’m unable to increase it later. This procedure, while it occurs only twice a week or so, is something I’m trying to eliminate. I’ll talk about that later.

One disadvantage of pairing up the batteries to produce the required 24v is that these serial pairs can become imbalanced. Same with lead acid, so nothing new here. Most people just let it be, but I am a bit more careful. Once a year or whenever I have good shore power, I’ll use the Quattro to fully charge the battery bank and then disconnect all the batteries. If I’m still living aboard, the Skylla provides clean enough output that I can use it to provide 24v in the absence of a battery bank. I will take my small 12.8v lithium specific charger (1.5amps), which you can buy for $30 on Amazon and charge each 12.8v battery individually. By topping them off individually in this manner, when I pair them back up, they are re-balanced. The Victron batteries have balancing capabilities within the cells of each individual battery, but NOT across a serial pair. While this is probably not necessary, the cost of the batteries is making me do whatever I can do ensure they are happy. I went nearly a year before this balancing procedure and the batteries remained quite balanced - again my procedure is probably overkill.

Problems/Holes:

All is not perfect on our system. With lithium, each 12.8v battery is composed of 4cells. If any of those cells drop below a certain voltage or go above a certain voltage or overheat, they will be damaged irreparably. That’s why you have a BMS to monitor all the cells individually. However, the BMS only warns of dangerous conditions - you need something to act on that warning.

Battery Disconnect: 

You need a device to disconnect loads when the voltage is low, as indicated by the BMS. Initially I installed the Victron BP-220 which can handle 220 amps continuous and a lot more for short periods, supposedly. It was a reminder never to trust the marketing material without testing. The first time I used my hydraulic passarelle, the BP-220 melted. The Amel was not initially wired with lithium in mind, so the “control” wires that are connected to switches and have low current are not separated from the “power supply” wires when they get to the main switches. If you could take the time to separate that out, 220 amp capacity of the BP-220 would be plenty, but as is, it’s not sufficient. 

My current solution involves not letting the battery bank state of charge drop below 25%. I’ve confirmed with Victron that this will make it very very unlikely that you’ll have a cell low voltage condition.  Moreover, the inverter will stop inverting if the BMS indicates a cell low voltage condition.

Does anyone have a solenoid they can suggest? The VE.BUS BMS load disconnect functions by sending out a signal at battery voltage (eg - 25.8v) when all is good and drops to open circuit when the load needs to be disconnected. The VE.BUS BMS can power a solenoid that requires up to 2amps but obviously I would prefer something that is bi-stable so it doesn’t draw power continuously when all is good. I would prefer something that can handle at least 600amps continuous.

Charging Disconnect:

To prevent cell over temperature or over voltage, there needs to be a way to cut off charging. The VE.BUS BMS communicates with the Quattro, the Skylla and the MPPT. If the BMS signals a problem, the Victron devices will stop charging.

The Mastervolt alternator, however, is not controlled by the VE.BUS BMS. According to Victron documentation, the VE.BUS BMS has an output that provides 10mA of power to control a simple relay in response to battery over voltage conditions. The Mastervolt controller has a “reg-on” brown wire that allows you to safely cut off charging on the Mastervolt alternator. All you need to do is disconnect it. Mastervolt provides this functionality and states that you can wire it to a switch and use it to safely turn off the alternator to give additional motoring power when needed. So it’s safe for the alternator, per Mastervolt. But, despite trying 24v relays and even 12v relays, the VE.BUS BMS could not power a relay to control the reg-on and consequently turn off the alternator if necessary. 

I had a long discussion with Victron engineers and they suggested I try this very low current relay. 

https://www.schneider-electric.com/en/product/RSL1PREU/interface-plug-in-relay---zelio-rsl---1-c-o---48-v-dc---6-a---with-led/

Any thoughts on this? It needs to require a lower power draw to activate than a normal 24 or 12v Hella automotive relay.

In the meantime, the Victron engineers suggested I set the absorption voltage on the Mastervolt to 27.5 volts. By doing that, it does not fully charge the lithium bank and with that low of absorption voltage, the likelihood we have a cell overvoltage condition is very very small. In fact, given lithium’s distaste of persistent high state of charge, I may lower the absorption voltage further so I don’t keep the batteries at high SOC during extended motoring.

Shorepower charging and state of charge:

Another problem I have tried to solve is regarding state of charge while plugged in for long periods. Personally I don’t like to plug in because of horror stories I’ve heard regarding bad wiring at marinas and zincs disappearing very quickly. In fact, I’ve been tied up for 2 months during this hurricane season and I have not even bothered to plug in - I just let the solar array take care of the batteries.  We even run AC when it’s too hot.

Now the challenge when you’re either plugged in or not using much energy as is the case when you’re not moving much is how to keep the batteries from sitting at 100%. Lead acid thinking requires you to keep the batteries fully charged - in the lithium world that will reduce their lifespan. 

One solution is to set a lower absorption voltage when you’re plugged into shore power for a long time, so that the chargers stop charging at say, 60% state of charge. This is done through trial and error because one of the advantages of lithium is very little voltage drop with respect to state of charge. That, of course, makes it hard to determine state of charge. But trial enough or more accurately, error enough and you’ll figure it out.

MPPT choice and location:

If I could do it again, I would have bought the SmartSolar vs. the BlueSolar. I like monitoring and tracking and the SmartSolar has the bluetooth transmitter built in. The BlueSolar does not and requires that I add in a bluetooth transmitter, which is fine except for the fact that the same data comm port on the MPPT is used by the charging cutoff signal from the VE.BUS BMS. 

I also don’t like the current location of the BlueSolar MPPT as it heats up the main battery switch compartment where it’s located. I don’t want to vent it to the passage berth area as we don't want to add more heat to our living spaces. I also don’t want to vent it outside using the existing battery vent because I would rather not have salt mist enter a compartment full of wires. I’m sure Amel thought of that when they installed the vent in the engine room - I am not going to take unnecessary risk with my expensive lithium setup by altering the vent system in the battery compartment. What I will likely do is mount it in the engine room and use the old wiring for the Dolphin 30 amp charger to extend the solar panel feed to the MPPT. Then I’ll just use the same 2 pairs of 50mm2 wires that the Quattro uses in order to feed solar charging current to the batteries. 

Safety, Better Batteries, Drop In Solutions, Replacing Batteries.

A few final notes - LifePo4 is very different and far safer than the lithium batteries that you hear about blowing up in phones and laptops. You can research it, so I’ll leave it at that. Some have suggested that cheaper and better battery technologies are right around the corner. To me, I could wait until next year to buy a computer and I might get a faster one, but then I will not have a computer for a year. We are circumnavigating now and really enjoy having a functioning power system now. After experiencing life on lithium, I would never go back to lead acid/gel/agm. Moreover, I knew some people when I was back in grad school (known for their engineering department) who were talking about solid state batteries and that wasn’t last year. :) The statements I’ve read about solid state batteries being right around the corner have been from the same institution. Perhaps this time, it’s true, but I am not holding my breath.

Some companies are selling you drop in solutions. Just buy their lithium batteries and you can use your existing charging system and it just works. Hopefully after reading this description of my experience with lithium, you will not send money to them. Otherwise you’ll probably be sending more money once your batteries die unexpectedly.

Finally, some have wondered what happens if a battery fails in the middle of the Tuomotus, stating that you can’t find a lithium replacement out there and you’re screwed. Well, while I agree you won’t find a lithium replacement in every harbor in the world, you aren’t really screwed. All of my chargers can handle standard gel/lead acid/agm batteries and if necessary, you can replace them with lead acid and just change the charging profile. But the reality is that with the ability for lithium to take deep discharges with no damage, I would probably just take a battery pair out of my bank and keep going. But this does highlight the fact that you should be able to change the charging profile yourself. It’s not rocket science and if I can do it, anyone can.

Next steps for me:

As I mentioned, I am not 100% happy with the alternator charge (high voltage) disconnect situation and the missing low voltage load disconnect solution. I’m all ears on how I can fix those.

The next project for me, which could be easy or cause intense brain damage is wiring the Onan generator to automatically start at 30% SOC and turn off at 75% SOC. It’s relatively easy to get the Onan generator to start with the Victron system, but I want the generator to start, with no load for 30 seconds, then turn on the chargers, run for the necessary time to charge up to 75% SOC and then turn off chargers and run the generator for an additional 60 seconds to cool down before shutting off the generator. 

I think I’ve found a solution in the programmable relays in the Quattro paired with the relay in the BMV-712, but I need to consult with my smart friends first before I try this solution. With it implemented, my system would remove one of the heretofore seemingly unavoidable annoyances of sailing an electricity hungry sailboat - constantly monitoring the battery SOC. The solar would provide most of my power and if that proves not enough, the generator would automatically kick in, maintaining the built in protections (overheat/oil pressure/etc) that the Onan has.

Anyways, this post is far too long already. Hopefully this opens up a discussion and I’m happy to answer any questions on things that I have not explained clearly or omitted, which I’m sure there are many.

-- 

Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Rob Dillmann
 

Dear Scott,

Thank you for your extensive and interesting report on your transfer to Lithium. Valuable insights and helpful for my next upgrade of the electrical system.
I have no solutions to offer for your final questions (lack of expertise), but I have one suggestion.

I upgraded the electrical system of our Mango recently, including the Victron Quattro 3000 and  Victron solar controllers, but still working with 600 Ah plus 300 Ah lead acid. 
I agree completely with your experiences with the Quattro as the central intelligent unit for your power supply. We included however also a Victron isolating transformer for safety reasons and for flexibility (it accepts both 220 and 110V, and 50 and 60Hz). 

Best regards,

Rob Dillmann
Amel Mango 43






Op di 3 sep. 2019 om 15:03 schreef Scott SV Tengah <Scott.nguyen@...>:

A little over a year ago, I replaced my nearly stock Amel 54 “comfort package” lead acid system with a nearly complete LifePo4, aka lithium battery system. The system was designed with the help of Victron engineers and of course a marine electrician, but I will say that many marine electricians today try to apply lead acid thinking to lithium and it leads to many unintended consequences. I promised many of you a writeup on my 1 year experience with my system, what works and what could be better.

 

I’ll start by saying that lithium truly is life changing. All of the 230v appliances we ran earlier, we can run without genset. On battery, we can cook with induction, run aft aircon all night, heat water, run the boiler, wash clothes and dishes and moreover, charging just got a 20-25% boost due to lithium’s charging efficiency. The only thing that won’t run is that I can’t start up the scuba compressor on inverter power, probably due to startup spike. I can probably install a capacitor to fix that, but it’s low priority and I’m fine starting the genset for that. Despite the cost of my system, I would do it again in a heartbeat. It is the best change we have made on the boat, without question.

 

I’ll also preface by saying what I’ve said many a time before - I am not an engineer by any means but I simply research, ask questions, execute and then test extensively. I rely on people smarter than me to advise me on things I don’t understand, of which there are many. It’s not a cheap system but given that we are at the front end of a multi-year circumnavigation, I believe the amortized cost is lower than using flooded lead acid/gel/agm. That is, if you don’t kill the batteries, which an improperly setup system may very well do.

 

My old system consisted of the following:

 

  • Twelve 100AH 12v gel batteries, wired in serial pairs to make 24v and then wired in parallel to make 600 amp hours.
  • Dolphin 100amp primary and 30amp secondary charger
  • Mastervolt 110amp 24v changer on the main engine with Alpha Pro 1 regulator
  • Xantrex power monitor

 

I’ll start by listing the components of my current electrical system, specifically items related to my lithium installation:

 

  • Six Victron Smart lithium 150ah 12.8v batteries, wired in serial pairs to make 25.6v and then wired in parallel to make 450AH.
  • Victron VE.BUS BMS
  • Victron Quattro 24v/5000va/120amp charger/inverter
  • Victron Skylla-i 24/80 (3) charger with correct adaptor to allow it to talk to the VE.BUS BMS
  • Mastervolt 110amp 24v changer on the main engine with Alpha Pro 2 regulator
  • Three LG Neon2 320watt solar panels for a total of 960w wired in parallel
  • Victron BlueSolar 150/35 MPPT charger with the correct adaptor to allow it to talk to the VE.BUS BMS
  • Victron BMV-712 battery monitor

 

Let’s walk through the individual components and why I chose them, what I like about them and what could be better. The system is NOT perfect and some of the problems I’m trying to solve for are still outstanding. Part of this writeup is to ask for your help, especially those of you who studied/worked with this stuff, and to explain my decision making and have you tell me, with a reasoned argument and evidence, why a different way is better. Or provide solutions for holes in my system - I’ll be the first to say that they exist.

 

You will note heavy representation by one brand - Victron. That was intentional because one of my biggest fears is that the batteries die and if I had lots of different brands for the various components, they will each point fingers at the other and I would be left holding the bag. Victron has a great reputation and my experience with them has been great. I’m sure Mastervolt or Battle Born or XXXXYYY brand is great, so don’t take my component selection as saying that Victron is the best and no other brand will work. 

 

Batteries: We’ll start with the battery selection. Because lithium can easily go 2000 cycles even with 80% DOD, you don’t need as much bank capacity to equal usable capacity compared to lead acid. With my original 600AH setup and no more than the recommended 40% DOD, the usable AH is 600*.4=240AH. Given the batteries are 12.8v, you need an even number of them to make 25.6v, so I could have gone with 4 of them and had the same usable capacity (300*.8 = 240AH) as the original 600AH setup. But I went for 6 batteries and got 450AH and (450*.8=360AH) usable capacity. Sure, even more is nice, but the reality is that my solar array only puts out about 200-250AH a day, so additional battery bank capacity would simply extend the interval for running the generator and 230v chargers. I probably won’t install a wind generator for various reasons. Each pair of batteries is connected serially using copper bars. The Electrican tried battery cables as jumper wires (“but this worked fine on every other <lead acid> setup I’ve installed!”) but the current going through them caused the cables to overheat. The copper bars aren’t perfect because they can exert force on the battery posts, but that’s the best solution I’ve found to date. Note that each pair is wired to the Amel installed +ve and -ve post in the battery compartment using equal length battery cables.

 

The Victron Smart lithium 150AH batteries fit in the stock battery location under the passage berth. They were nearly the perfect size, only requiring me to trim a bit of the wooden bracing under the “lid” of the passage berth bed. Some may put larger batteries horizontally, but Victron explicitly cautions against that. For warranty reasons, I will follow their advice. The batteries are considerably lighter than my previous gel batteries - I lost 258kg in battery weight alone. That’s actually a bit of a problem because now we list about 1-1.5 degrees to port and my port side gelcoat is under the waterline and requires weekly scrubbing! Nearly half the battery compartment is empty but I’m too afraid to put anything in the same location as those expensive batteries. 

 

I also added 3 fuses, 450 amps each. 

 

My understanding is that Amel didn’t install battery bank fuses because they didn’t want you to lose bow thruster, windlass or other critical high draw components when voltage drops and consequently amperage skyrockets. This is not really a concern with lithium, where the voltage drop is negligible even when I draw 200amps from them. I can easily run the bow thruster or the windlass with engine/genset off. Even to my non-engineer mind, having non-fused big batteries like this just sounds dangerous. Hearing about a few Amel battery bank explosions reinforces my fear, so I went for the fuses. I zip tie backup fuses and also jumper wires nearby in case the installed fuses fail to handle the currents Amel 54s require. No problems so far.

 

BMS: With Victron, I went for the VE.BUS BMS system. All the pigtails from the six batteries run in serial to the BMS. As you may know, the BMS monitors the battery condition, down to the cell level.

 

230v Charger/Inverter: I chose the Quattro 24/5000/120 because it barely fit into the spot where the old Dolphin 100A charger sat, in the engine room. This gives me 5000va (watts, more or less, depending on the 230v appliance) of inverter capacity and can charge at up to 120amps. With lithium, the batteries can take nearly the full charging current up until high 90s state of charge, so I opted for lots of charging capacity for shorter genset runtime. We aren’t on shore power much, so I can’t comment except to say that much of the time, your shore power connection can’t handle that much amperage, so you’ll be limited by that.

 

The inverter capacity allows us to run virtually everything on the boat. The admiral has been known to run the toaster, microwave and induction cooker at the same time. While the batteries can easily handle that in terms of current delivery, if you draw 200amps like that, you’ll drain the battery bank in about 2.5 hours. Note that lithium capacity does not drop dramatically like lead acid with increasing current.  For lead acid, when they say 100amp hours, they mean 5 amps an hour for 20 hours (test load=capacity/20hrs). If you draw 100amps on a lead acid battery, it will probably last 10 minutes and result in a massive voltage drop, increasing your amperage even more. That is not the case with lithium. 

 

Why did I choose the 5000va Quattro and not 3000va model or the 8000va model? 

 

Well for the 3000va model, I figured there would be times where the admiral or crew overload the inverter. It’s not the end of the world if you have a 3000va inverter, but since the batteries can easily handle 5000va of draw, I figured why not? Also the ratings are made for operation at 25 degrees Celsius. It might get a bit hotter on my boat so I wanted excess capacity. Additionally the 5000va fits perfectly, albeit sideways, where the old Dolphin 100amp charger fit. We had to add a wood board for backing, but it fits perfectly and takes advantage of the ventilation provided by Amel to the original Dolphin 100amp. After a year of usage, I have never noted output nor charging current reduction due to heat. The 8000va model is larger and heavier and I am not sure it will fit in the stock Dolphin 100 location. Additionally, the standby draw is twice (2 amps+) the standby draw of the 5000va. There is some power save mode but that makes my analog Amel voltmeter jump constantly, which I avoided for longevity reasons. For me, the Quattro 24/5000/120 was the goldilocks solution.

 

By using the Quattro, you take the original Amel 230v automatic switch out of the system as the Quattro does it internally. There are advantages to that, as you will see later.

 

Installing the Quattro requires an ethernet cable and FOUR 50mm^2 battery cables from the engine room to the battery compartment. That means you need to break the epoxy seal between the engine compartment and the passage berth, located on the floor on the forward end of the “passage”. After this, you will re-epoxy the hole so the watertight separation is re-established. I also ran an additional ethernet cable in case of failure of the original cable.

 

I also added a Victron Skylla-i 24/80 charger. This is intentional for two reasons: (1) If the main Quattro fails, I can easily rewire the shore power lead and run the Skylla. This duplicates the redundancy we had with the original Dolphin 100amp / 30 amp separate chargers. (2) Additionally, this gives me a way to plug-in at marinas that are primarily 110v and then double them up to produce 220v. This is common in the Americas. The problem with this system is that it still retains 60hz, but many of the appliances in our 54 do not run on 60hz. So the concept is that we can use the Skylla to charge the lithium batteries and have the Quattro provide 230v/50hz power via the inverter.  The Skylla is wired using the old cables that were connected to the Dolphin 100amp charger. If Amel believes the cables can handle 100amps, I presume it can handle 80amps. The Skylla fits where the old Dolphin 30 amp charger fit, right next to the Quattro.

 

When the Quattro detects mains/genset power, it will immediately pass it through to the boat’s internal 230v wiring. If that shore power is 60hz, you have a problem. I specifically asked Victron if I could force the Quattro to just charge and not pass through shore power and the answer was a definitive NO. So the Skylla solves that problem if the situation ever arises where we need to plug in for longer periods in locations that only provide 60hz power. I’m sure an expensive frequency converter would be more seamless, but we don’t anticipate many if any long periods of plugging in in the Americas.

 

Alternator and Charge Controller: The original Mastervolt Alpha Pro 1 alternator charge controller does not have a lithium charging profile and had to be replaced with a newer model. Unfortunately Victron does not make alternators nor alternator charge controllers. Note that most alternators will burn up when subjected to the charging loads imposed by lithium. With lead acid, the maximum current is only required for a short period as lead acid cannot accept full charging current once you get above say 60% state of charge. So your typical 100 amp alternator will only be required to output 100amps for a short period. With lithium, it will be required to output the full amperage until the battery bank is nearly full. Many alternators cannot handle the heat generated from this and will burn out quickly. Speaking to Mastervolt engineers, they were adamant that the Mastervolt 24/110 can easily handle outputting the full current for long periods as lithium requires. For extra measure, I installed a temperature sensor on the alternator to reduce output if the alternator overheats. Additionally, I limited maximum output to 90 amps. This is done via an ethernet adaptor from Mastervolt.

 

Renewable power generation: I installed a stainless arch above my davits and mounted LG Neon2 panels. I wanted the 350w model but they only had 320w in stock. Note that the size is exactly the same, it’s just some panels have higher yield than others. This gives me 960w total. I opted to connect them in parallel, which requires thicker cables (13mm2) and more of them, but given my research, I believe parallel will allow higher daily total output when there is partial shading from sails/masts. Electricians often push for serial wiring as it’s easier. The solution we came up with is to have a pair of wires from each panel to a junction/switch in the lazarette and then a single pair from there to the MPPT charge controller.

 

For charge controlling, I opted for the Victron BlueSolar 150/35 MPPT controller. The 150v gives me the voltage capacity in case I decide to re-wire the panels to serial and the 35 amps is just at the level recommended for 1000 watts of solar.

 

The electricians installed it in the same passage berth compartment as the main switches, which after a while, I realized was not ideal. More about that later.

 

Finally, I installed a Victron BMV-712 battery monitor in the same location as the original Xantrex monitor, on the Amel 24v panel. It fit perfectly.

 

Operation:

 

Lithium thinking is very different from conventional lead acid thinking. The batteries do not like to be kept at 100%, in fact, for optimal lifetime, you should keep them at 40-50% state of charge. I generally try to keep them between 40-80%. The renewables will add on average, 200-250 amp hours a day in tropical areas. That almost covers my daily usage. But energy is like money, you will never have enough and if you’re not careful, you will end up using more than you have!

 

With lithium, you can think of the batteries as a “gas tank” for energy. After a year’s usage, the amount I put in via charging is only 2.5% less than the amount drawn out. That 2.5% is charging inefficiency. With lead acid, the charging inefficiency/loss around 10x as much, so when you draw 20 amps, you need to put in 25 amps to replace it! That means the same 1000 watt solar array with lithium is effectively a 750watt array with lead acid. And given that lithium can accept full charge current up to high 90s SOC, very little generated solar power is "wasted" by batteries not being able to accept full current at high SOC, a common problem with lead acid. With the thousands of cycles available in lithium and the charging efficiency, my primary concern is keeping the batteries between 40-80%. 

 

Right now, every 3 days, on overage, I’ll start up the genset and run both chargers (200amp total) for around 30 minutes. My procedure is that I’ll turn off all the chargers (not simple on the Quattro as you need to login via the MK3-USB connector and use the VE-Config software and reduce charging current to zero amps. Then I’ll start the Onan 11kw and run it for 30 seconds before turning on all the chargers to allow oil to circulate. The Skylla 80 amp is wired into the original 230v panel switch for the 100amp Dolphin. I haven’t gotten around to changing the label yet. :) I wire that to AC output 2 on the Quattro, so the Skylla only runs on shorepower/genset, rather than inverter. It also delays switching on by 2 minutes, I believe. Everything else is wired to run off the inverter. Yes, even the water heater and aircon.

 

To turn off the genset, I’ll turn off all the chargers and then let the genset run with no load for 1 minute before shutting it down. This cool down procedure is probably overkill, but specifically recommended by Onan. Then I’ll reset the Quattro to max charging power in case the laptop dies and I’m unable to increase it later. This procedure, while it occurs only twice a week or so, is something I’m trying to eliminate. I’ll talk about that later.

 

One disadvantage of pairing up the batteries to produce the required 24v is that these serial pairs can become imbalanced. Same with lead acid, so nothing new here. Most people just let it be, but I am a bit more careful. Once a year or whenever I have good shore power, I’ll use the Quattro to fully charge the battery bank and then disconnect all the batteries. If I’m still living aboard, the Skylla provides clean enough output that I can use it to provide 24v in the absence of a battery bank. I will take my small 12.8v lithium specific charger (1.5amps), which you can buy for $30 on Amazon and charge each 12.8v battery individually. By topping them off individually in this manner, when I pair them back up, they are re-balanced. The Victron batteries have balancing capabilities within the cells of each individual battery, but NOT across a serial pair. While this is probably not necessary, the cost of the batteries is making me do whatever I can do ensure they are happy. I went nearly a year before this balancing procedure and the batteries remained quite balanced - again my procedure is probably overkill.

 

Problems/Holes:

 

All is not perfect on our system. With lithium, each 12.8v battery is composed of 4cells. If any of those cells drop below a certain voltage or go above a certain voltage or overheat, they will be damaged irreparably. That’s why you have a BMS to monitor all the cells individually. However, the BMS only warns of dangerous conditions - you need something to act on that warning.

 

Battery Disconnect: 

 

You need a device to disconnect loads when the voltage is low, as indicated by the BMS. Initially I installed the Victron BP-220 which can handle 220 amps continuous and a lot more for short periods, supposedly. It was a reminder never to trust the marketing material without testing. The first time I used my hydraulic passarelle, the BP-220 melted. The Amel was not initially wired with lithium in mind, so the “control” wires that are connected to switches and have low current are not separated from the “power supply” wires when they get to the main switches. If you could take the time to separate that out, 220 amp capacity of the BP-220 would be plenty, but as is, it’s not sufficient. 

 

My current solution involves not letting the battery bank state of charge drop below 25%. I’ve confirmed with Victron that this will make it very very unlikely that you’ll have a cell low voltage condition.  Moreover, the inverter will stop inverting if the BMS indicates a cell low voltage condition.

 

Does anyone have a solenoid they can suggest? The VE.BUS BMS load disconnect functions by sending out a signal at battery voltage (eg - 25.8v) when all is good and drops to open circuit when the load needs to be disconnected. The VE.BUS BMS can power a solenoid that requires up to 2amps but obviously I would prefer something that is bi-stable so it doesn’t draw power continuously when all is good. I would prefer something that can handle at least 600amps continuous.

 

Charging Disconnect:

 

To prevent cell over temperature or over voltage, there needs to be a way to cut off charging. The VE.BUS BMS communicates with the Quattro, the Skylla and the MPPT. If the BMS signals a problem, the Victron devices will stop charging.

 

The Mastervolt alternator, however, is not controlled by the VE.BUS BMS. According to Victron documentation, the VE.BUS BMS has an output that provides 10mA of power to control a simple relay in response to battery over voltage conditions. The Mastervolt controller has a “reg-on” brown wire that allows you to safely cut off charging on the Mastervolt alternator. All you need to do is disconnect it. Mastervolt provides this functionality and states that you can wire it to a switch and use it to safely turn off the alternator to give additional motoring power when needed. So it’s safe for the alternator, per Mastervolt. But, despite trying 24v relays and even 12v relays, the VE.BUS BMS could not power a relay to control the reg-on and consequently turn off the alternator if necessary. 

 

I had a long discussion with Victron engineers and they suggested I try this very low current relay. 

https://www.schneider-electric.com/en/product/RSL1PREU/interface-plug-in-relay---zelio-rsl---1-c-o---48-v-dc---6-a---with-led/

Any thoughts on this? It needs to require a lower power draw to activate than a normal 24 or 12v Hella automotive relay.

 

In the meantime, the Victron engineers suggested I set the absorption voltage on the Mastervolt to 27.5 volts. By doing that, it does not fully charge the lithium bank and with that low of absorption voltage, the likelihood we have a cell overvoltage condition is very very small. In fact, given lithium’s distaste of persistent high state of charge, I may lower the absorption voltage further so I don’t keep the batteries at high SOC during extended motoring.

 

Shorepower charging and state of charge:

 

Another problem I have tried to solve is regarding state of charge while plugged in for long periods. Personally I don’t like to plug in because of horror stories I’ve heard regarding bad wiring at marinas and zincs disappearing very quickly. In fact, I’ve been tied up for 2 months during this hurricane season and I have not even bothered to plug in - I just let the solar array take care of the batteries.  We even run AC when it’s too hot.

 

Now the challenge when you’re either plugged in or not using much energy as is the case when you’re not moving much is how to keep the batteries from sitting at 100%. Lead acid thinking requires you to keep the batteries fully charged - in the lithium world that will reduce their lifespan. 

 

One solution is to set a lower absorption voltage when you’re plugged into shore power for a long time, so that the chargers stop charging at say, 60% state of charge. This is done through trial and error because one of the advantages of lithium is very little voltage drop with respect to state of charge. That, of course, makes it hard to determine state of charge. But trial enough or more accurately, error enough and you’ll figure it out.

 

MPPT choice and location:

 

If I could do it again, I would have bought the SmartSolar vs. the BlueSolar. I like monitoring and tracking and the SmartSolar has the bluetooth transmitter built in. The BlueSolar does not and requires that I add in a bluetooth transmitter, which is fine except for the fact that the same data comm port on the MPPT is used by the charging cutoff signal from the VE.BUS BMS. 

 

I also don’t like the current location of the BlueSolar MPPT as it heats up the main battery switch compartment where it’s located. I don’t want to vent it to the passage berth area as we don't want to add more heat to our living spaces. I also don’t want to vent it outside using the existing battery vent because I would rather not have salt mist enter a compartment full of wires. I’m sure Amel thought of that when they installed the vent in the engine room - I am not going to take unnecessary risk with my expensive lithium setup by altering the vent system in the battery compartment. What I will likely do is mount it in the engine room and use the old wiring for the Dolphin 30 amp charger to extend the solar panel feed to the MPPT. Then I’ll just use the same 2 pairs of 50mm2 wires that the Quattro uses in order to feed solar charging current to the batteries. 

 

Safety, Better Batteries, Drop In Solutions, Replacing Batteries.

 

A few final notes - LifePo4 is very different and far safer than the lithium batteries that you hear about blowing up in phones and laptops. You can research it, so I’ll leave it at that. Some have suggested that cheaper and better battery technologies are right around the corner. To me, I could wait until next year to buy a computer and I might get a faster one, but then I will not have a computer for a year. We are circumnavigating now and really enjoy having a functioning power system now. After experiencing life on lithium, I would never go back to lead acid/gel/agm. Moreover, I knew some people when I was back in grad school (known for their engineering department) who were talking about solid state batteries and that wasn’t last year. :) The statements I’ve read about solid state batteries being right around the corner have been from the same institution. Perhaps this time, it’s true, but I am not holding my breath.

 

Some companies are selling you drop in solutions. Just buy their lithium batteries and you can use your existing charging system and it just works. Hopefully after reading this description of my experience with lithium, you will not send money to them. Otherwise you’ll probably be sending more money once your batteries die unexpectedly.

 

Finally, some have wondered what happens if a battery fails in the middle of the Tuomotus, stating that you can’t find a lithium replacement out there and you’re screwed. Well, while I agree you won’t find a lithium replacement in every harbor in the world, you aren’t really screwed. All of my chargers can handle standard gel/lead acid/agm batteries and if necessary, you can replace them with lead acid and just change the charging profile. But the reality is that with the ability for lithium to take deep discharges with no damage, I would probably just take a battery pair out of my bank and keep going. But this does highlight the fact that you should be able to change the charging profile yourself. It’s not rocket science and if I can do it, anyone can.

 

Next steps for me:

 

As I mentioned, I am not 100% happy with the alternator charge (high voltage) disconnect situation and the missing low voltage load disconnect solution. I’m all ears on how I can fix those.

 

The next project for me, which could be easy or cause intense brain damage is wiring the Onan generator to automatically start at 30% SOC and turn off at 75% SOC. It’s relatively easy to get the Onan generator to start with the Victron system, but I want the generator to start, with no load for 30 seconds, then turn on the chargers, run for the necessary time to charge up to 75% SOC and then turn off chargers and run the generator for an additional 60 seconds to cool down before shutting off the generator. 

 

I think I’ve found a solution in the programmable relays in the Quattro paired with the relay in the BMV-712, but I need to consult with my smart friends first before I try this solution. With it implemented, my system would remove one of the heretofore seemingly unavoidable annoyances of sailing an electricity hungry sailboat - constantly monitoring the battery SOC. The solar would provide most of my power and if that proves not enough, the generator would automatically kick in, maintaining the built in protections (overheat/oil pressure/etc) that the Onan has.

 

Anyways, this post is far too long already. Hopefully this opens up a discussion and I’m happy to answer any questions on things that I have not explained clearly or omitted, which I’m sure there are many.

 

 

--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Scott SV Tengah
 

Rob,

Does the Victron Isolation Transformer take 60hz input and output 50hz? 
--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Andrew & Kate Lamb
 

An excellent write up Scott and very useful.

 

We  have had a Victron Quattro 5000/120 since 2013 and have been very pleased with this. It is clear that lithium is the next step.

 

Andrew

Ronpische

Sm472

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Scott SV Tengah
Sent: Tuesday, September 3, 2019 4:35 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Converting my Amel 54 to lithium batteries: what I did, what I like and what I don't like (after one year of full time live aboard use)

 

Rob,

Does the Victron Isolation Transformer take 60hz input and output 50hz? 
--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

ngtnewington Newington
 

Hi Scott,

Very interesting to read about your project. You have obviously enjoyed the whole process and the challenge.
Would it be impertinent to ask how much it all cost? 
I will stick with my AGM’s until they eventually die, they are two and a bit years old, but when the time comes Lithium is certainly an option...

Kind regards

Nick
S/Y Amelia
Kefalonia
AML 54-019


On 3 Sep 2019, at 16:04, Andrew & Kate Lamb <andrew.lamb@...> wrote:

An excellent write up Scott and very useful.

 

We  have had a Victron Quattro 5000/120 since 2013 and have been very pleased with this. It is clear that lithium is the next step.

 

Andrew

Ronpische

Sm472

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Scott SV Tengah
Sent: Tuesday, September 3, 2019 4:35 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Converting my Amel 54 to lithium batteries: what I did, what I like and what I don't like (after one year of full time live aboard use)

 

Rob,

Does the Victron Isolation Transformer take 60hz input and output 50hz? 
--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Brent Cameron
 

Fantastic write up Scott.  I kept writing down questions and then erasing them as I read further and you answered them.  I’d love to see a schematic at one point but I think most of it is pretty self-evident from your description.  I do have a few questions:

  1. Are your 450A fuses wired into each of the 2x12V battery pairs before you gang them together in parallel - i.e., if one fuse blows, it takes down two of your Lithium 12V batteries leaving two more 2x12V pairs to continue to provide the load at 24V?
  2. Not to be pedantic but I suspect that you mean that the pig tails connected to your VE.BUS BMS and your batteries are daisy chained rather than serial connections?  I gather that the Victron batteries send digital information to the VE.BUS BMS so the information isn’t aggregated by putting them in serial configuration as would happen if they were using an analog signal - such as voltage?  So in your system, battery 1 connects to battery 2… connects to battery 6 which connects to the BMS?  I was never sure how these BMS systems connected to the batteries and control them when the batteries  are serially and then parallel connected as in your configuration.  If the system senses an issue with say battery 3 in your system, I would expect that the BMS should somehow signal battery 3 to shut down - but then what happens to battery 4 (the other battery in the series configuration to make 24V) - does it sense getting back fed by the other two banks of batteries and shut down itself? (Late addition - Now I see that you are using the BP-220 to shut down the battery - but it seems to me it would take down the entire system if one battery failed.. no?). This leads me to the next point….
  3. With respect to your question about the solenoid… Can the VE.BUS BMS be configured to talk to three BP-220’s, each protecting one 2x12V pair of batteries?  I.e. you would have your battery fuses inline with the BP-220’s and then bring them together in parallel. This might also address my question on how the BMS system commands the shut down… I gather the batteries themselves do not shut down but rather you need a system like the BP-220 to shut them down when commanded to by the VE.BUS BMS?  If I’m right, this would simply drop a 24V battery pair in the event of a bad cell and not the entire bank - presumably, you’d also want it to trigger some sort of alarm to let you know you’d just lost 33% of your capacity.
  4. Did you consider the LFP-Smart 25.6V/200A batteries and if so, why did you discard them: 
    1. Cost; 
    2. Size (they seem to be 33% higher, 37% deeper and only 2% more narrow so I guess you may have had an issue fitting them into the existing battery compartment?);
    3. Didn’t need the extra power 33% power, or;
    4. Other
  5. I guess it isn’t that much work to wire up two 12V to get 24V - especially as that is the way the boat originally came anyway but I was thinking it might have simplified the situation where you have to shut down a bank of batteries because of a bad cell.
  6. With respect to your idea about automagically starting and stopping your 11KW Onan to keep the bank between 30-75% in the absence of solar, you might think of adding a normally open switch triggered by closing the engine room hatch as a safety feature in your autostart circuit so the genset didn’t fire up automagically when you were working on or around it. (The switch would be open when the hatch is open preventing your Onan from starting while you were down there working on/or around it).
Again, this is a fantastic write up Scott.  I think you will do much to advance the cause (along with the work Bill is doing to help get reduced prices) of bringing these magnificent sailing machines into a much more energy independent paradigm. 


Brent Cameron, Future Amel Owner and Amel Owner’s Registry Moderator

On Sep 3, 2019, 1:23 PM -0400, ngtnewington Newington via Groups.Io <ngtnewington@...>, wrote:
Hi Scott,

Very interesting to read about your project. You have obviously enjoyed the whole process and the challenge.
Would it be impertinent to ask how much it all cost? 
I will stick with my AGM’s until they eventually die, they are two and a bit years old, but when the time comes Lithium is certainly an option...

Kind regards

Nick
S/Y Amelia
Kefalonia
AML 54-019


On 3 Sep 2019, at 16:04, Andrew & Kate Lamb <andrew.lamb@...> wrote:

An excellent write up Scott and very useful.

 

We  have had a Victron Quattro 5000/120 since 2013 and have been very pleased with this. It is clear that lithium is the next step.

 

Andrew

Ronpische

Sm472

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Scott SV Tengah
Sent: Tuesday, September 3, 2019 4:35 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Converting my Amel 54 to lithium batteries: what I did, what I like and what I don't like (after one year of full time live aboard use)

 

Rob,

Does the Victron Isolation Transformer take 60hz input and output 50hz? 
--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com


--
Brent Cameron

Future Amel Owner & Amel Owner Registry Moderator

Oro-Medonte, Ontario, Canada

Joerg Esdorn
 

Thanks very much, Scott.  Excellent write-up.  I have a few questions and comments.

1.  The A55 comes with a switch that in the "on" position, turns on the generator automatically if the SOC goes below 60%.  Amel cautions owners, however, that it may not be a good idea to have this switch on since the generator will then run for 2 hours and all kinds of things can happen if you happen to be not on the boat while this is happening.  I've never had it "on" but I've certainly had the "low water" alarm come on because there was some issue with the saltwater intake.    If I had not been on the boat, I might have destroyed my generator. 
2.  Does your 5KW charger get hot when it is charging the batteries?  Where is it installed - in the engine room?  I'm asking because I was on another boat with Lithium batteries and they had very powerful cooling fans for the chargers even though charging was limited to 20% of battery capacity.  The fans were very noisy which for me, sleeping in the cabin next to the chargers, was a problem.  This was in late 2017, the system was designed by Mastervolt engineers and the boat was new then.  Do you have a limit on the charging current?
3.  On the A55, I cannot use my 2.5KW inverter for high current things like the water heater, AC, water maker.  This is done by Amel to protect  the gel batteries, I'm sure, through the wiring of the 230V switchboard.  I was surprised that you didn't mention this in your writeup - presumably the A54 has the same setup for the original switchboard but you are getting around this issue by not wiring your 5KW combi through the old switchboard?  I'm wondering how easy it would be to change the wiring on the switchboard and just add another inverter (in parallel) rather than starting from scratch.  
4.  When you leave your boat for extended periods, can't you just leave the batteries without charger?  If you start them at 100%, it should take many months before they're down to 25%, right?  

Scott, again many thanks for this.  My gel batteries may have another year in them or may not.  It's great to have someone as competent as you doing the major lifting on the choice of battery I will need to make soon! 

Joerg Esdorn
A55 #53
Kincsem, currently anchored by Gibraltar

Paul Brown
 

Hi Scott 

Thank you again for sharing all this information and it certainly helps my awareness and thoughts moving forward 

As you know the previous owner of my A55 upgraded the system to almost a complete MasterVolt lithium, charging, inverter and monitoring system in 2015, which works extremely well and reliability to date, it has been certainly a life changing experience aboard as I too enjoy anchoring for extended periods and living off the grid with minimal use of the generator. 

We have away to go by increasing solar from 550w/24v to hopefully 1100w/24v which I figure would allow total off the grid solar generation continuous without generator along with upgrading all appliances to a suitable inverter - this is my grey area as to what development I really need to accomplish this 

I have a question please, how do you manage maintaining an equal balance of all your batteries in the bank if only running the bank between 40-80% SOC. Mastervolt has advised me that I should charge the bank to 100% at least every fortnight to balance the batteries otherwise it is likely to damage them. This is an area that needs clarification in respect to manage the SOC to optimise long term life of the system. 

Currently I need to run the generator on average 4-5 hours per week when at anchor, at that time I can make water, run the washer, use the air-con’s and of course charge to 100%.. it would be wonderful not ever running the generator and everything from batteries,, but how can this be achieved???

I look forward to following this thread as if lithium maybe the ideal system it does need some questions answered to establish an ideal system, considering it would be the most costly system but certainly could be a great investment.

I wish there was a blue print off the shelf 

Kind regards Paul - Fortuna II A55#17


On 4 Sep 2019, at 8:16 am, Joerg Esdorn via Groups.Io <jhe1313@...> wrote:

Thanks very much, Scott.  Excellent write-up.  I have a few questions and comments.

1.  The A55 comes with a switch that in the "on" position, turns on the generator automatically if the SOC goes below 60%.  Amel cautions owners, however, that it may not be a good idea to have this switch on since the generator will then run for 2 hours and all kinds of things can happen if you happen to be not on the boat while this is happening.  I've never had it "on" but I've certainly had the "low water" alarm come on because there was some issue with the saltwater intake.    If I had not been on the boat, I might have destroyed my generator. 
2.  Does your 5KW charger get hot when it is charging the batteries?  Where is it installed - in the engine room?  I'm asking because I was on another boat with Lithium batteries and they had very powerful cooling fans for the chargers even though charging was limited to 20% of battery capacity.  The fans were very noisy which for me, sleeping in the cabin next to the chargers, was a problem.  This was in late 2017, the system was designed by Mastervolt engineers and the boat was new then.  Do you have a limit on the charging current?
3.  On the A55, I cannot use my 2.5KW inverter for high current things like the water heater, AC, water maker.  This is done by Amel to protect  the gel batteries, I'm sure, through the wiring of the 230V switchboard.  I was surprised that you didn't mention this in your writeup - presumably the A54 has the same setup for the original switchboard but you are getting around this issue by not wiring your 5KW combi through the old switchboard?  I'm wondering how easy it would be to change the wiring on the switchboard and just add another inverter (in parallel) rather than starting from scratch.  
4.  When you leave your boat for extended periods, can't you just leave the batteries without charger?  If you start them at 100%, it should take many months before they're down to 25%, right?  

Scott, again many thanks for this.  My gel batteries may have another year in them or may not.  It's great to have someone as competent as you doing the major lifting on the choice of battery I will need to make soon! 

Joerg Esdorn
A55 #53
Kincsem, currently anchored by Gibraltar

svperegrinus@yahoo.com
 

With regard to the brown wire and a Mastervolt Alpha Pro regulator: the On/Off control of the regulator _is_ the brown wire.  In fact, if the brown wire is not interrupted at installation time via an interface to your engine's ignition key or to an oil pressure switch, then the regulator will always be on 24x7 and it will either burn up the alternator windings or discharge the batteries, whichever happens first.  Therefore I agree that yes, it is up to Victron to provide the signal necessary for you to install the relay that will interrupt the brown wire and turn off the regulator.  Hopefully the Schneider switch Victron proposes will address your issue.

Non-automated options for switching off the Alpha Pro regulator, short of manually pulling off the brown wire, include:

1.  Install an in-line manual switch

2.  Set up a "Alternator Off" / "Alternator On" virtual switch buttons on a Mastervolt EasyView screen.  This is what I have done.  I've never had occasion to need to use these buttons in anger, as the regulator has proven to be 100% reliable with regards to voltages, floats, temperatures, etc., but it is important to have this emergency kill available, just in case.

3.  Connect via USB to the Mastervolt MasterBus.  On the MasterAdjust software, select the option to "Configure" the regulator.  This will turn off the regulator and it will remain off until the configuration is again locked down.

NICOLAS KLENE <n.klene@...>
 

Hi Ameliens 
I have been following with great interest your discussions, on converting to lithium .
I am actively looking for a SM 2K , and it would be one of the first upgrade I would go through .
There is a young guy very knowledgable who could perhaps answer some of your question, check his posts on youtube , his name is William Prowse.
All the best 
Nick
Soon to be an Amel owner 
🚣‍♂️

Theo s/v Paloma
 

The Victron isolation transformer does not change frequency. It only up or down converts Voltage.
It works great!

Theo
s/v Paloma
Amel 50 #18

Arno Luijten
 

Hi Scott,

Thanks for your extensive report on the Lithium conversion.
Reading your post I notice the same challenge as I've been anticipating when moving to Lithium. Basically you want the batteries to stick at 70-80% if you keep the boat on shore-power and avoid keeping the batteries at 100% for extended periods. When at anchor this is more easy as there is typically no permanent feed of power into the battery similar to shore power so the SOC will go up and down anyway. At the same time you want to avoid unnecessary cycles on the battery. There is no easy solution as ideally you want the chargers to stop charging at 80% unless there is a reason to go to 100% (i.e. start of a longer passage). At the same time you do need to feed the onboard systems even if your batteries should stop charging. Most battery chargers can also act as power-supply. So just isolating the batteries from the charger when the batteries reach 80% SOC would solve that problem. But how to handle the situation when the on-board systems require more power then the charger can supply and the "disconnect-from-shore-power" event without having a power-dip on all your on-board systems during the time it takes to re-connect the batteries. When at anchor ideally you need to anticipate when the renewable sources will no longer be able to support the on-board systems and the batteries need to brought back on-line. For the latter, as you rightfully say, you can determine the voltage the chargers need to produce to halt the charging process at 70-80% but there is no easy way to alter this voltage if you need to go to 100%. Ideally you should be able to simply activate a certain charging profile for all charging devices. I have not found a solution for this myself.
Balancing the batteries is another issue as this is typically performed at 100%SOC requiring the need to occasionally push the batteries to 100%SOC. There are systems that do continuously balancing but that required the usage of individual cells (https://www.ev-power.eu/).

So to me it seems the Marine industry had not yet made the full change to support Lithium batteries in the best way possible. The question is if you want to wait for that point if we will ever see it happen. By that time there may be another technology surpassing Lithium.

Arno Luijten
SV Luna,
A54-121

Peter Forbes
 

Your Amel 54 will last for at least another 30 years. I plan to wait for next step in technology - probably in control devices.

Peter Forbes
Carango
Amel 54 -035
La Rochelle 

On Thu, 5 Sep 2019 at 13:14, Arno Luijten <arno.luijten@...> wrote:
Hi Scott,

Thanks for your extensive report on the Lithium conversion.
Reading your post I notice the same challenge as I've been anticipating when moving to Lithium. Basically you want the batteries to stick at 70-80% if you keep the boat on shore-power and avoid keeping the batteries at 100% for extended periods. When at anchor this is more easy as there is typically no permanent feed of power into the battery similar to shore power so the SOC will go up and down anyway. At the same time you want to avoid unnecessary cycles on the battery. There is no easy solution as ideally you want the chargers to stop charging at 80% unless there is a reason to go to 100% (i.e. start of a longer passage). At the same time you do need to feed the onboard systems even if your batteries should stop charging. Most battery chargers can also act as power-supply. So just isolating the batteries from the charger when the batteries reach 80% SOC would solve that problem. But how to handle the situation when the on-board systems require more power then the charger can supply and the "disconnect-from-shore-power" event without having a power-dip on all your on-board systems during the time it takes to re-connect the batteries. When at anchor ideally you need to anticipate when the renewable sources will no longer be able to support the on-board systems and the batteries need to brought back on-line. For the latter, as you rightfully say, you can determine the voltage the chargers need to produce to halt the charging process at 70-80% but there is no easy way to alter this voltage if you need to go to 100%. Ideally you should be able to simply activate a certain charging profile for all charging devices. I have not found a solution for this myself.
Balancing the batteries is another issue as this is typically performed at 100%SOC requiring the need to occasionally push the batteries to 100%SOC. There are systems that do continuously balancing but that required the usage of individual cells (https://www.ev-power.eu/).

So to me it seems the Marine industry had not yet made the full change to support Lithium batteries in the best way possible. The question is if you want to wait for that point if we will ever see it happen. By that time there may be another technology surpassing Lithium.

Arno Luijten
SV Luna,
A54-121

--
Best wishes
Peter Forbes
+44 (0) 7836 209730

Scott SV Tengah
 
Edited

Nick,

I can't recall exactly, but 15k euros excluding the solar arch/panels/MPPT is probably about right.
--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Scott SV Tengah
 

Brent,

Glad you found some value in it. I went through a lot of brain damage to get to where I am today, so no need for others to repeat my mistakes.

Answers to your questions:

1) That is correct, 1 fuse per 25.8v pair.
2) You are correct - no worries, if I'm wrong about something, I'd rather have someone point it out than for me to remain blissfully ignorant about my ignorance. :) They are daisy chained. I tried to use the BP-220 but that failed due to overcurrent. I think the Victron system responds to over/under voltage in a very blunt manner - I don't believe it shuts down nor disconnects individual batteries. One of the cells in one of the batteries is over voltage and the all of the chargers stop charging. In the under voltage situation, it just cuts off your load to prevent battery damage until the charger(s) have raised voltage back above the lower limit.

Each battery can be monitored (temp and cell voltages) via bluetooth. I surmise if your BMS cut everything off, you could check individually and then remove the battery (or more accurately the battery and the one it's serially connected to) from the bank and continue on.

3) My understanding of the low voltage cutoff is that it's "global"  - so the VE.BUS BMS can't instruct a specific BP-220 to load disconnect. I actually think your idea of putting three BP-220s in the system, one for each battery pair MIGHT work to protect the batteries, but as I said, the load disconnect signal is global. Nowhere in the documentation does it show the capacity to assign specific a specific load disconnector to specific batteries. I'm loathe to spend more money on BP-220s when a single one should have been able to handle the passarelle. 

4) The height on the 25.6/200 is a problem. Even with my 12.8/150 model, I had to trim a bit of the bracing on the lid. I just looked and noted the 12.8/200 is reported to be the same size as the 12.8/150. I'm not sure this model existed at the time I installed my system AND it seems a bit odd that you get 33% more capacity with the same size and only 10% more weight. So it may be a typo. But if not, it's an easy way to get more capacity.
https://www.victronenergy.com/upload/documents/Datasheet-12,8-&-25,6-Volt-lithium-iron-phosphate-batteries-Smart-EN.pdf

6) Great idea in general. I will say that my Volvo isn't ground isolated. A previous owner replaced the 12v alternator and didn't put the isolated version in, so the negative is connected to the bonding system. I've been told by very knowledgable Amel reps that it's not ideal to have the 12v negative connected, but it's not a huge problem. Hell, most boats are setup that way. I'm careful, so we installed an additional "main battery switch" whereby I can disconnect the 12v negative when I'm anchored for a while or tied up, so as to eliminate the connection between 12v negative and bonding. This also prevents the genset/engine from starting, obviously. 

But your idea is very good.

--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Scott SV Tengah
 

Joerg,

1) I need to do more research when I get ready to wire my genset to start automatically, but I have heard that the Onan will shut itself down if it detects low oil pressure, over temperature on the coolant, etc. Does anyone know if this is true?

2) It can get warm, yes. It's in the engine room where the old Dolphin 100 was located. There is an air intake directed right at it, which Amel installed for the Dolphin. The Quattro has its own fans and they will kick on after a long period of charging or high load inverting. But I can only hear it if the engine room hatch is open and I've never noted charging current being limited or inverting wattage being limited, so at least with my usage, heat has not been a problem. Another post mentioned it would be nice to have the Quattro trigger the Amel-installed exhaust fans if temps got above XXXX, which I think is a great idea. The Quattro has programmable relays, so that shouldn't be difficult.

3) The way the Quattro is setup is that you have AC-Out1 which feeds both passthrough shorepower/genset 230v AND inverter 230V. There is then AC-Out2 which only feeds passthrough shorepower/genset 230v. The only thing we have wired to AC-Out2 is the Victron Skylla-i 24/80 charger. 

I didn't do the actual connection but had a long discussion with the electrician to ensure the practical operation was how I wanted it. He didn't note any difficulties in wiring it up, so I presume it wasn't hard.

4) First off, I wouldn't want them staying at 100% or anywhere near that. Lithium irreversibly loses capacity if you hold them at high SOC. Secondly, there is a small load from the 24-12v downconverters and frankly, I don't want to lose all the saved settings on the radio, B&G, etc. If the boat is in the water, I want to have power in case the bilge pumps need to operate. Call me paranoid, but well, things happen!


--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Scott SV Tengah
 

Paul,

I generally try to keep it between 40-80% but yes, the Victron literature tells you to charge to 100% every month or two to allow the BMV-712 battery monitor to re-calibrate. I believe it also allows your cells to balance out. We do this but only once every month or two.

My understanding is that if you don't do super heavy draws (eg - 1C or 450 amps in my case) or charge to the absolute highest voltage recommended, the batteries will tend to stay in balance. That has been our experience over the last year. 

To be safe, once a year, I will charge up the bank completely using the Quattro then disconnecting all the batteries and charging them individually with a 12.8v 1.5amp charger until completely full. That's to maintain balance - most likely major overkill, but the cost of the system is quite high, so I'm ok overdoing it. :)

I think you will still need to run the genset now and then. If we have excess energy (eg - over 80% SOC), we will run the water maker to burn off energy. But often, we just do it while motoring. I considered adding another 220 watts (Sunpower flexible panels) on the Bimini. That would put me close to 1200 watts. But the cost and complication of that was too much for me right now (plenty of other higher priority items!) and I resigned to using the genset twice a week. At the end of the day, we should probably use the genset a bit, otherwise my understanding is that non-use can damage it also.


--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Scott SV Tengah
 
Edited

Correct, the Reg-on wire does turn on/off the alternator. 

I installed the manual in-line switch. I will, in fact, turn off the alternator manually during long motoring days, especially if it's sunny.  However, I don't really like a system that requires me to think about it because there will inevitably be one time when I forget. And with lithium, it's just too expensive to leave the health of the system dependent on me never screwing up and forgetting.

As you alluded, none of the manual systems will not correct an over voltage condition. That is, unless you either monitor the batteries constantly through bluetooth or wire the VE.BUS BMS to sound an alarm at over voltage. But then that goes back to requiring your perfect intervention.  So we need to figure out a way to get the VE.BUS BMS "charge disconnect" signal to disconnect the Mastervolt Reg-on wire. Hopefully that Schneider relay draws so little current that the 10mA VE.BUS Bms charge disconnect circuit can trigger it.
--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Scott SV Tengah
 

I considered waiting too and we decided we wanted to be able to take advantage of the benefits now, during our circumnavigation. 

It is a personal decision though. The technology isn't to the point where you just order it off the shelf, drop it in and it all works perfectly. I think even with current systems, you could achieve that, but it requires lots of thinking and planning to get there. It's simply too new for most marine electricians to understand. Lead acid has been around for nearly 100 years and can take the abuse. I would argue that, given the number of Amel's I've heard of with lead acid battery bank explosions/problems, lead acid isn't there either.

For us, however, the ability to run the washer, the dishwasher, the toaster, the microwave, the induction cooker, the projector, the water maker, the water heater, aircon,...all without turning on the generator and getting a massive boost in charging efficiency and high load output efficiency - well I wouldn't want to give that up and wait for something that may be better at some indeterminate point in the future. 

The problem with lithium is that there isn't a boat-specific drop in solution. It's too new and there are far too few users for any company to put the R&D into that. I surmise when the new technology comes out, the same lag will be there. 

--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com