Topics

Lithium Batteries under Consideration


Dean Gillies
 
Edited

Hi all,
12 months ago I ordered 12x new Rolls S12-128AGM batteries to replace Stella's (A54-154) waning 5 year old battery bank.  
My thinking at the time was that I would seek another 5 years from AGM's before seriously considering lithium.
The pandemic happened and I was unable to return to the boat (in the UK) in 2020, so I cancelled my battery order.

Fast forward 12 months and I am thinking again about my battery replacement. During the pandemic I bought a caravan (RV) which is fitted with a 12Vx 200Ah lithium battery, and it has given me some good first-hand experience of using a lithium system in an off-grid scenario.  In practical terms, I am impressed by its ability to accept high charge rates even when SOC is high, and also to operate effectively with stable voltages when in low SOC states, even when delivering high currents.     My boat use-case is ideally 6 months constant cruising and 6 months in storage, although the current cycle will be 18 months in storage due to the pandemic. I am least impressed by the logistics of maintaining a lithium battery during long periods of storage.

That said, I am now considering making the jump to lithium when I (hopefully) return to the UK in 2020.
I don't want to get involved in a lithium "project" and I'm not particularly interested in turning Stella into a "smart boat".
I'm also not interested in retiring my generator, and I am happy to continue using this for AirCon and Laundry appliances, so I don't need a big invertor, and I don't want to replace the cabling between batteries and Engine Room charging devices.

My preferred path would be to install "drop-in" replacement lithium batteries, and then upgrade any other components necessary to ensure safe and reliable operation.
I believe the main thing I will need to re-configure/augment is my 175A charger to ensure it doesn't overheat with too much constant load, and doesn't destroy itself in a HV battery disconnect.
Any other critical things I should consider here?   

The lithium batteries I would prefer are the 24V models since they should always be properly balanced by the BMS, whereas the 12V models need to be separately managed for proper balancing in a 24V system (just like Lead Acid batteries do).  I understand about not having 12V redundancy for engine starting, and I'm comfortable with my contingencies there. 

I considered the BattleBorn 24V/50Ah batteries, and apart from the strange terminal configuration making them not "drop-in", these would seem to be a good choice. However I cannot find a supplier in the UK. Has anyone purchased these in the UK?  Has anyone purchased them for shipping to the UK from the US?

My other serious contender is the Relion RB24V50.  This has a slightly lower max discharge current (50A) than the BB battery (60A) which is important particularly for bow thruster operation but the terminal arrangement means that it is a true drop-in replacement AND it is available for purchase in the UK.  I wonder if anyone has any experience of this battery, or other Relion batteries? 

Cost vs power
The set of 12x AGM batteries is GBP2800 and provides about 250Ah of usable capacity at 24V without taking the batteries below about 65% SOC (which is my preference). So lets say about GBP11 per Ah of usable capacity.

A set of 8x 24Vx50Ah Relion batteries would cost about GBP8000 and give a usable capacity of about 280Ah without taking the batteries below 30% SOC. That is therefore about GBP28 per Ah of usable capacity.

The rule of thumb seems to be that the lithium option is about 2.5 times more expensive than AGM for equivalent capacity. 
Does that stack up with other experiences or did I miss something?

Weights
The 12x AGM batteries total mass is 393.6kg whereas the 8x lithium batteries weigh in at 105.6kg
That's a weight saving of 288kg.
I know that Stella, like other A54's, has a slight list to one side, but I just can't remember if it's port or starboard, can someone please remind me which it is?

Hmmm, I didn't intend this post to be quite so involved, but just typing it has helped to clarify my thinking :-)

Cheers
Dean
SY Stella A54-154
Currently (still) ashore in Ardrossan, Scotland.
 
 


 
   
  


  


Brent Cameron
 

Dean, Battle Born is the US distributor for Dragon Fly Energy. In the UK, the same batteries are sold as Transporter Energy. This is what Brian on Delos installed.   In addition to the alternator regulators you will need to ensure your chargers support a Lithium profile as well. 

Brent

On Nov 13, 2020, 8:58 PM -0500, Dean Gillies <stella@...>, wrote:

[Edited Message Follows]

Hi all,
12 months ago I ordered 12x new Rolls S12-128AGM batteries to replace Stella's (A54-154) waning 5 year old battery bank.  
My thinking at the time was that I would seek another 5 years from AGM's before seriously considering lithium.
The pandemic happened and I was unable to return to the boat (in the UK) in 2020, so I cancelled my battery order.

Fast forward 12 months and I am thinking again about my battery replacement. During the pandemic I bought a caravan (RV) which is fitted with a 12Vx 200Ah lithium battery, and it has given me some good first-hand experience of using a lithium system in an off-grid scenario.  In practical terms, I am impressed by its ability to accept high charge rates even when SOC is high, and also to operate effectively with stable voltages when in low SOC states, even when delivering high currents.     My boat use-case is ideally 6 months constant cruising and 6 months in storage, although the current cycle will be 18 months in storage due to the pandemic. I am least impressed by the logistics of maintaining a lithium battery during long periods of storage.

That said, I am now considering making the jump to lithium when I (hopefully) return to the UK in 2020.
I don't want to get involved in a lithium "project" and I'm not particularly interested in turning Stella into a "smart boat".
I'm also not interested in retiring my generator, and I am happy to continue using this for AirCon and Laundry appliances, so I don't need a big invertor, and I don't want to replace the cabling between batteries and Engine Room charging devices.

My preferred path would be to install "drop-in" replacement lithium batteries, and then upgrade any other components necessary to ensure safe and reliable operation.
I believe the main thing I will need to re-configure/augment is my 175A charger to ensure it doesn't overheat with too much constant load, and doesn't destroy itself in a HV battery disconnect.
Any other critical things I should consider here?   

The lithium batteries I would prefer are the 24V models since they should always be properly balanced by the BMS, whereas the 12V models need to be separately managed for proper balancing in a 24V system (just like Lead Acid batteries do).  I understand about not having 12V redundancy for engine starting, and I'm comfortable with my contingencies there. 

I considered the BattleBorn 24V/50Ah batteries, and apart from the strange terminal configuration making them not "drop-in", these would seem to be a good choice. However I cannot find a supplier in the UK. Has anyone purchased these in the UK?  Has anyone purchased them for shipping to the UK from the US?

My other serious contender is the Relion RB24V50.  This has a slightly lower max discharge current (50A) than the BB battery (60A) which is important particularly for bow thruster operation but the terminal arrangement means that it is a true drop-in replacement AND it is available for purchase in the UK.  I wonder if anyone has any experience of this battery, or other Relion batteries? 

Cost vs power
The set of 12x AGM batteries is GBP2800 and provides about 250Ah of usable capacity at 24V without taking the batteries below about 65% SOC (which is my preference). So lets say about GBP11 per Ah of usable capacity.

A set of 8x 24Vx50Ah Relion batteries would cost about GBP8000 and give a usable capacity of about 280Ah without taking the batteries below 30% SOC. That is therefore about GBP28 per Ah of usable capacity.

The rule of thumb seems to be that the lithium option is about 2.5 times more expensive than AGM for equivalent capacity. 
Does that stack up with other experiences or did I miss something?

Weights
The 12x AGM batteries total mass is 393.6kg whereas the 8x lithium batteries weigh in at 105.6kg
That's a weight saving of 288kg.
I know that Stella, like other A54's, has a slight list to one side, but I just can't remember if it's port or starboard, can someone please remind me which it is?

Hmmm, I didn't intend this post to be quite so involved, but just typing it has helped to clarify my thinking :-)

Cheers
Dean
SY Stella A54-154
Currently (still) ashore in Ardrossan, Scotland.
 
 


 
   
  


  

--
Brent Cameron

Future Amel Owner & Amel Owner Registry Moderator

Oro-Medonte, Ontario, Canada


Dean Gillies
 

Thanks Brent,
The problem I've found is that Transporter Energy don't supply the 24V battery model. They only supply the 12V battery.  I've seen good reviews of the Battleborn product in this forum and elsewhere.

Good point about the profiles. I have circa 2010 Mastervolt mains chargers which I believe have lithium profiles, and a Victron solar controller which I know definitely does have the lithium profile.

I'll check up on the Mastervolt products, and also that the Alternator external regulator is compatible.

Best regards
Dean
SY Stella A54-154


Elja Röllinghoff Balu SM 222
 

He Dean
By the calkulation for the price by AH you have to think abaut the time foe working in good contitione the AGM batteries maybe 5-8 years
Li maybe 10-12 years ( we dont now realy )
I think two month agow to change to LI in this winter but it seams to dificult for my an now i thange by a new charge system victron multiplus , victron solar charger , and new agm Batteries an then i can change in 5 yaers by LI Batteries

Elja
SM Balu 222

Von meinem iPhone gesendet


Courtney Gorman
 

I just installed 12 12v Relion batteries and 2 40v chargers everything was a straight swap 
Batteries 900$ each Chose the 40v because they can use any shore voltage and can run at the same time if wanted like with the Generator 
Obviously no long term experience but my failed chargers killed a 1 year old bank of AGMs so easy decision 
Cheers 
Courtney 
Trippin 
54 #101
Brunswick 


On Nov 13, 2020, at 8:57 PM, Dean Gillies <stella@...> wrote:

Hi all,
12 months ago I ordered 12x new Rolls S12-128AGM batteries to replace for Stella's (A54-154) waning 5 year old battery bank.  
My thinking at the time was that I would seek another 5 years from AGM's before seriously considering lithium.
The pandemic happened and I was unable to return to the boat (in the UK) in 2020, so I cancelled my battery order.

Fast forward 12 months and I am thinking again about my battery replacement. During the pandemic I bought a caravan (RV) which is fitted with a 12Vx 200Ah lithium battery, and it has given me some good first-hand experience of using a lithium system in an off-grid scenario.  In practical terms, I am impressed by its ability to accept high charge rates even when SOC is high, and also to operate effectively with stable voltages when in low SOC states, even when delivering high currents.     My boat use-case is ideally 6 months constant cruising and 6 months in storage, although the current cycle will be 18 months in storage due to the pandemic. I am least impressed by the logistics of maintaining a lithium battery during long periods of storage.

That said, I am now considering making the jump to lithium when I (hopefully) return to the UK in 2020.
I don't want to get involved in a lithium "project" and I'm not particularly interested in turning Stella into a "smart boat".
I'm also not interested in retiring my generator, and I am happy to continue using this for AirCon and Laundry appliances, so I don't need a big invertor, and I don't want to replace the cabling between batteries and Engine Room charging devices.

My preferred path would be to install "drop-in" replacement lithium batteries, and then upgrade any other components necessary to ensure safe and reliable operation.
I believe the main thing I will need to re-configure/augment is my 175A charger to ensure it doesn't overheat with too much constant load, and doesn't destroy itself in a HV battery disconnect.
Any other critical things I should consider here?   

The lithium batteries I would prefer are the 24V models since they should always be properly balanced by the BMS, whereas the 12V models need to be separately managed for proper balancing in a 24V system (just like Lead Acid batteries do).  I understand about not having 12V redundancy for engine starting, and I'm comfortable with my contingencies there. 

I considered the BattleBorn 24V/50Ah batteries, and apart from the strange terminal configuration making them not "drop-in", these would seem to be a good choice. However I cannot find a supplier in the UK. Has anyone purchased these in the UK?  Has anyone purchased them for shipping to the UK from the US?

My other serious contender is the Relion RB24V50.  This has a slightly lower max discharge current (50A) than the BB battery (60A) which is important particularly for bow thruster operation but the terminal arrangement means that it is a true drop-in replacement AND it is available for purchase in the UK.  I wonder if anyone has any experience of this battery, or other Relion batteries? 

Cost vs power
The set of 12x AGM batteries is GBP2800 and provides about 250Ah of usable capacity at 24V without taking the batteries below about 65% SOC (which is my preference). So lets say about GBP11 per Ah of usable capacity.

A set of 8x 24Vx50Ah Relion batteries would cost about GBP8000 and give a usable capacity of about 280Ah without taking the batteries below 30% SOC. That is therefore about GBP28 per Ah of usable capacity.

The rule of thumb seems to be that the lithium option is about 2.5 times more expensive than AGM for equivalent capacity. 
Does that stack up with other experiences or did I miss something?

Weights
The 12x AGM batteries total mass is 393.6kg whereas the 8x lithium batteries weigh in at 105.6kg
That's a weight saving of 288kg.
I know that Stella, like other A54's, has a slight list to one side, but I just can't remember if it's port or starboard, can someone please remind me which it is?

Hmmm, I didn't intend this post to be quite so involved, but just typing it has helped to clarify my thinking :-)

Cheers
Dean
SY Stella A54-154
Currently (still) ashore in Ardrossan, Scotland.
 
 


 
   
  


  


 

Transporter Energy distributes the Battle Born batteries in Europe under the brand Transporter Fact Sheet
For more information or a Custom Bundle Quote contact:
Justin Richardson 
Justin@...
+44 1323 405375  • Work
+44 7713 140946  • Mobile
Tell him that I referred you for an Amel Discount

Bill
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Fri, Nov 13, 2020 at 7:57 PM Dean Gillies <stella@...> wrote:
Hi all,
12 months ago I ordered 12x new Rolls S12-128AGM batteries to replace for Stella's (A54-154) waning 5 year old battery bank.  
My thinking at the time was that I would seek another 5 years from AGM's before seriously considering lithium.
The pandemic happened and I was unable to return to the boat (in the UK) in 2020, so I cancelled my battery order.

Fast forward 12 months and I am thinking again about my battery replacement. During the pandemic I bought a caravan (RV) which is fitted with a 12Vx 200Ah lithium battery, and it has given me some good first-hand experience of using a lithium system in an off-grid scenario.  In practical terms, I am impressed by its ability to accept high charge rates even when SOC is high, and also to operate effectively with stable voltages when in low SOC states, even when delivering high currents.     My boat use-case is ideally 6 months constant cruising and 6 months in storage, although the current cycle will be 18 months in storage due to the pandemic. I am least impressed by the logistics of maintaining a lithium battery during long periods of storage.

That said, I am now considering making the jump to lithium when I (hopefully) return to the UK in 2020.
I don't want to get involved in a lithium "project" and I'm not particularly interested in turning Stella into a "smart boat".
I'm also not interested in retiring my generator, and I am happy to continue using this for AirCon and Laundry appliances, so I don't need a big invertor, and I don't want to replace the cabling between batteries and Engine Room charging devices.

My preferred path would be to install "drop-in" replacement lithium batteries, and then upgrade any other components necessary to ensure safe and reliable operation.
I believe the main thing I will need to re-configure/augment is my 175A charger to ensure it doesn't overheat with too much constant load, and doesn't destroy itself in a HV battery disconnect.
Any other critical things I should consider here?   

The lithium batteries I would prefer are the 24V models since they should always be properly balanced by the BMS, whereas the 12V models need to be separately managed for proper balancing in a 24V system (just like Lead Acid batteries do).  I understand about not having 12V redundancy for engine starting, and I'm comfortable with my contingencies there. 

I considered the BattleBorn 24V/50Ah batteries, and apart from the strange terminal configuration making them not "drop-in", these would seem to be a good choice. However I cannot find a supplier in the UK. Has anyone purchased these in the UK?  Has anyone purchased them for shipping to the UK from the US?

My other serious contender is the Relion RB24V50.  This has a slightly lower max discharge current (50A) than the BB battery (60A) which is important particularly for bow thruster operation but the terminal arrangement means that it is a true drop-in replacement AND it is available for purchase in the UK.  I wonder if anyone has any experience of this battery, or other Relion batteries? 

Cost vs power
The set of 12x AGM batteries is GBP2800 and provides about 250Ah of usable capacity at 24V without taking the batteries below about 65% SOC (which is my preference). So lets say about GBP11 per Ah of usable capacity.

A set of 8x 24Vx50Ah Relion batteries would cost about GBP8000 and give a usable capacity of about 280Ah without taking the batteries below 30% SOC. That is therefore about GBP28 per Ah of usable capacity.

The rule of thumb seems to be that the lithium option is about 2.5 times more expensive than AGM for equivalent capacity. 
Does that stack up with other experiences or did I miss something?

Weights
The 12x AGM batteries total mass is 393.6kg whereas the 8x lithium batteries weigh in at 105.6kg
That's a weight saving of 288kg.
I know that Stella, like other A54's, has a slight list to one side, but I just can't remember if it's port or starboard, can someone please remind me which it is?

Hmmm, I didn't intend this post to be quite so involved, but just typing it has helped to clarify my thinking :-)

Cheers
Dean
SY Stella A54-154
Currently (still) ashore in Ardrossan, Scotland.
 
 


 
   
  


  


Scott SV Tengah
 

Dean, 

If you have the master volt 110/24 alternator you'll need the alpha pro 2 or later regulator. You'll also need the masterbus-usb interface to pick the lithium profile. No way to do it otherwise. 

If you have a bms that can send a signal out to indicate over or under voltage, it's possible to setup the alpha pro 2 to safely stop charging. Took me a while (and included the help of an engineer who used to break into car ecus for fun and profit) to figure it out but it's relatively simple at the end of the day. 

My victron mains and solar chargers are turned off by an external bms signal too, so no worries about high voltage disconnect. 

I'm curious how it's done with these drop in batteries - I simply don't know how they protect against hvd without destroying the alternator, mains charger and solar charger. Further if the battery is disconnected from the circuit, wouldn't you have a voltage spike, damaging your electronics? Hvd has happened to me on more than one occasion due to high charging currents on batteries that went slightly out of balance. Didn't happen until after the first year, so don't be overconfident if it doesn't happen right away. 

For long term storage if you're storing on the hard, just disconnect everything at 40-50%soc and the self discharge is negligible. 

With master volt I believe you can set a charging limit based on soc. With my victron I did a workaround where I have the programmable relay within the bmv712 battery monitor turn on the inverter at say 75% and run a 230v load (dehumidifer) until it drops to 45% or so. Dries the boat and keeps it from keeping the battery overcharged when I leave the boat for extended periods 

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


Scott SV Tengah
 

Ah yes and we listed to port prior to lithium. Even more so now. Full diesel tank helps though. 

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


ngtnewington Newington
 

Hi Dean, 
When I bought Amelia in 2017 I replaced the Onan. I spent about two months with no genset and there was no list. As soon as the new genset was installed we listed to port.
I also bought new Lifeline AGMs.
Still going 100%. I wanted Firefly at the time  but availability was the problem.
I understand the attractions of Lithium, but carbon foam AGM batteries are also very attractive. Firefly brand is the best but expensive and not available in the U.K.
Pure lead carbon AGM by Leoch are available in the U.K. £239 inc delivery. I am sure you could get a discount for 12. I have no personal experience with these batteries.

I currently use my boat for about 5 months per year. I have solar and wind. For the other seven months the solar keeps the batteries 100% charged. Whilst cruising I run the genset to make water, do the laundry etc for about 3 hrs per week. Call it 75 hours per year. So about 115 litres of diesel, one oil change and an oil filter pa.
I anticipate that my battery bank will last quite a long time...but who knows.
Now if I was to do it again now, that is buy a boat with the generator seized and dead.
I would not replace the generator.
I would go Lithium and big inverter and big solar and big alternator.
The boat would have less weight and no list and it would have saved money.
The thing is, you:
Have a good generator
Only use the boat six months pa
Not sure Lithium is worth the trouble and expense unless you are cruising full time.

If you had solar you would prolong the life of your AGM bank.

All the best and looking forward to rolling out effective vaccines so we can get back on track.

Nick 
S/Y Amelia Leros Gr
AML54-019



On 15 Nov 2020, at 02:13, Scott SV Tengah <Scott.nguyen@...> wrote:

Ah yes and we listed to port prior to lithium. Even more so now. Full diesel tank helps though. 

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


Elja Röllinghoff Balu SM 222
 

He Nick ,
He Dean
I think the A2 B charger 24/200 from sterling have a profile for Licium charging from Altinator

Elja
SM Balu
222

Von meinem iPhone gesendet


Dean Gillies
 

Hi Elja,
You are correct, maybe the Lithium batteries will last longer, but maybe not. we don't really know! 
I know from experience the AGM's should last 5 years.  I think its unlikely that the Lithium's would last 12.5 years. I will base my thinking on 7-8 years for the Lithium option which makes them effectively double the cost.

Brent, I think I've tracked down my Mastervolt (Chargemaster 24/100-3) chargers and as far as I can ascertain, they are adjustable via MasterBus for a lithium charging profile.

Still need to work out about the alternator charging ability. It's all a bit difficult from the other side of the planet!  
Many thanks
Dean
SY Stella
A54-154

 


Dean Gillies
 

Hi Courtney,
Thanks for that info. Its good to hear about the Relion brand. Sorry to hear about the AGM's, what happened to kill those so quickly?

Hi Bill,
Thanks for the info. Unfortunately, Transporter don't supply the 24V batter. I checked with Justin.

Cheers
Dean
SY Stella A54-154


Dean Gillies
 

Hi Scott,
Thanks for that info, very helpful. I was wondering about the alternator... I do have the MV Alpha 24/110 Alternator, but I don't know if I have the original or series II regulator.  Best info I can find at the moment says that series II was released around 2013, so most likely I don't have that and will need to upgrade to the Series II or III.

I believe HVD is handled best by avoiding it.  The chargers must be programmed to shutdown before HVD voltage is reached. For example the Relion RB24V50 HVD is 31.2V, whereas fully charged is 29.2V, so chargers can be programmed to shut down at say 29.5.

This can be programmed with the Mastervolt chargers and Series II/III regulators.  If a charger fault causes higher voltage, then as you suggest, its possible that a voltage spike on disconnect will result, possible destroying the faulty charger.  In theory, the other chargers should be shutdown at that stage, which may limit the damage.
When your battery imbalance occurred, did all of your strings disconnect simultaneously? 

I'm hoping to minimise the chance of battery imbalance by using 24V batteries rather than 2x12V pairs. This also provides 8 batteries in parallel, so I suspect it's less likely that all 8 batteries will disconnect simultaneously. All very difficult to predict of course without a test bench.

So the list issue favours AGM's, thanks for that info!

Cheers
Dean
SV Stella A54-154


Dean Gillies
 

Hi Nick,
Sounds like the lead batteries definitely help the list problem!

Good analysis, and I tend to agree about it being marginal for part-time cruising.  I have a good solar capability, and I'm sure I would get 5 years easily from some good AGM batteries.
I don't anticipate a big drop in Generator usage by changing to Lithium, and I like to run it for a reasonable time on a regular basis anyway just for good practice.

It looks like I'm getting close to an answer on the cost comparison on a drop-in replacement basis.
Its about GBP300 for a new Alpha Series III regulator, and another GBP200 for a USB interface to program the chargers, so that brings the Lithium package to about GBP8500 vs around GBP3000 or maybe a bit less for those Leoch Carbon AGM batteries.

So I save a heap of cash and don't list even more to port by sticking with the lead! Who knows what new toys I could buy with that GBP5500.

Very interesting exercise, I need to mull over this a little more.

Thanks all.
Dean
SY Stella A54-154 
 


Brent Cameron
 

I believe that you need to upgrade your Mastervolt Alpha I regulator to an Alpha III to support LiFePO4 batteries. 

Brent

On Nov 15, 2020, 5:00 AM -0500, Dean Gillies <stella@...>, wrote:
Hi Elja,
You are correct, maybe the Lithium batteries will last longer, but maybe not. we don't really know! 
I know from experience the AGM's should last 5 years.  I think its unlikely that the Lithium's would last 12.5 years. I will base my thinking on 7-8 years for the Lithium option which makes them effectively double the cost.

Brent, I think I've tracked down my Mastervolt (Chargemaster 24/100-3) chargers and as far as I can ascertain, they are adjustable via MasterBus for a lithium charging profile.

Still need to work out about the alternator charging ability. It's all a bit difficult from the other side of the planet!  
Many thanks
Dean
SY Stella
A54-154

 

--
Brent Cameron

Future Amel Owner & Amel Owner Registry Moderator

Oro-Medonte, Ontario, Canada


Courtney Gorman
 

Hi Dean I was at the Dock with charger and shore power 6 weeks while away from Trippin the charger died and batteries drained so low the alternator couldn’t be excited to start charging them.  Got a portable charger to get a smaller charge then alternator fully charged them but they fell below 24 volts within 30 minutes 
Total Bummer expensive lesson learned 


On Nov 15, 2020, at 5:05 AM, Dean Gillies <stella@...> wrote:

Hi Courtney,
Thanks for that info. Its good to hear about the Relion brand. Sorry to hear about the AGM's, what happened to kill those so quickly?

Hi Bill,
Thanks for the info. Unfortunately, Transporter don't supply the 24V batter. I checked with Justin.

Cheers
Dean
SY Stella A54-154


Scott SV Tengah
 

Alpha 2 is fine as that's what I have and it has a lithium profile. 
--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com


Scott SV Tengah
 

The hvd often occurs because one cell is over voltage. When that happens to me, if you look at the battery or bank level voltage, all looks fine. But that one cell is spiking. 

And if you don't cut off charging safely, and the cell goes above, i believe 4.2v, the entire battery is dead. Even if you can replace the cell, you now have a differentially aged battery. 

Point is that unless a charger is talking to the bms, it cannot detect cell level high voltage. 

If I understand right, seems the 24v parallel strings deal with individual battery hv and lv issues by disconnecting that one battery. For my system, the chargers were just shut off. 

I surmise as cells age they do it at different rates. Some develop higher resistance and therefore don't charge as fast. When I was drawing super high loads (150amps) and not fully charging often enough to trigger cell balancing, the imbalance reared it's ugly head. 

As you mention its unlikely that all batteries experience hv at the same time. What if you are leaving the boat in a very hot environment and the ambient temp spikes? High temp disconnect would affect all the batteries. How will your chargers and electronics deal with that? 

Also comparing longevity for cost comparisons implies that the only benefit of lithium is longer life. Consider that you will save 30% or more on generator runtime due to charging efficiency and high charge acceptance and the fact that you don't need to take it to 100% very often. And for us its nice to run all 230v without generator or even the 24v water maker all night but I understand you don't consider that a benefit. 

I'm full time for 2 years now and the batteries are as good as new. I know another a54 who has had it longer and they echo my experience. My experience with gel was that they declined linearly and then decayed exponentially until I got tired of charging every few hours. 

To me, the longevity is a nice benefit but definitely not the most important. 

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


Dean Gillies
 

Hi Courtney,
That's a tough lesson indeed.  Good luck with the Relion kit, that's a great amount of power for a good price. Unfortunately I cant get that kind of pricing in the UK.

Hi Scott/Brent,
Yes I've assumed I'll need to buy the Alpha Series 3 regulator if I proceed with Lithium.

Scott, regarding High Voltage Disconnect (HVD), the symptoms you have described are exactly what I'm hoping to avoid by using a 24V battery which is balanced end to end.  When a battery cell fades as you have described (increased resistance), and it's part of a series-connected string then the other cells and the other battery will be subjected to an overvoltage situation. If this overvoltage is sufficient to trigger a disconnect, then that string will be disconnected. If there are additional strings in parallel, then this should not cause too many problems since the other strings will assume the load and a significant voltage spike should not result. However, in this scenario I wonder how the battery with the faded cell will ever automatically recover, as logic dictates that the string with the faded battery will never be automatically re-balanced, and will shut down early on every full charge cycle.  What makes matters worse here is that the drop-in batteries have no mechanism to flag that this problem has occurred. The faded battery will just continue to fade, probably more and more quickly as time goes on. Having a system-level BMS like yours gives much more insight into such events and allows you to take action to restore the faded battery.

The high temperature disconnect is interesting. All the charging devices monitor their own temperature sensor, so the theory goes that they can self-protect.  However, the thing I've always had a problem with is where to locate the sensor.  If I've got 8 batteries and one temperature sensor, where do I put it? Near the top of the compartment is the likely sensible answer I suppose.  That would allow the chargers to react to a compartment-ambient temp inflicted disconnect where all batteries could possibly (unlikely) simultaneously disconnect. If one battery becomes hotter than the rest (most likely scenario), then that battery can dis-connect itself without causing system damage.  The high-temp cut-off for the RelIon 24V batteries is 80degC.

On the comparisons, my mind is still not made-up about life expectancy of the drop-ins. I know the theoretical cycle numbers look great, but we don't subject batteries to the theoretical cycling that the manufacturers test, so, for me, it remains to be seen.  I think the 12V drop-in pairs topology is particularly prone to earlier failure due to the hidden balancing problem.

As you say, personally my use-case for the boat derives no advantage from lesser gen-set usage, or overnight water-maker usage. In fact less gen-set usage in my case could well be classed as "under abuse".
     
Everyone has a different use-case for their boat, and if I was full-time liveaboard, I would go down the full-system path, maximise the solar, and certainly wouldn't be living aboard in Scotland lol. 

Cheers
Dean
SV Stella A54-154
 

 
     


Alan Leslie
 

Hi All,

I'm with Nick.
We have 12 x AGMs that we installed 4 years ago with battery balancers to ensure the voltage across the series batteries stays equal and we have had ZERO problems so far. Elyse has 600W of solar and a wind generator and when we are at the dock the mains charger is on as well. We keep the frig and one freezer running all the time.
At sea we use the genset to charge the batteries and other 220V requirements. We rarely let the batteries drop below 85% and are religious about not overcharging them. We have a 3 stage external regulator on the engine alternator to ensure the right charging profile, AND I installed a switch in the cockpit so I can disconnect the field wire at the regulator for when the batteries are fully charged from being at the dock and we make short trips to the fuel dock or the travel lift so the alternator doesn't ramp up to 28.8 V every time the engine is started.
I am sure that internally regulated engine alternators on boats are what kills house batteries. Those internal regulators are really designed for automotive applications mainly charging start batteries, they ramp up to 28.8V and stay there - all day - no good for deep cycle batteries.
Its an endless discussion it seems!
Cheers
Alan
Elyse SM437