[Edited Message Follows]

Fellow Amelians,

I have been following these Lithium threads with great interest as i really thought that with the cost of LiFePO4 batteries coming down, and the advent of "drop in" replacements for LA batteries, perhaps the time had come to seriously consider replacing our aging AGM bank with Lithium.

BUT, reading all this thread so far, I'm now no longer sure.

Our 660Ah AGM bank has performed well for 6 years - but we look after it really well - balancers on each battery string, never discharge to less than 85%, 600W of MPPT controlled solar., externally regulated 175A alternator (with a field disconnect switch to prevent over charging), always plugged in at the dock etc

Two concerns I had with Lithium were, the peak discharge rate required by the bow thruster and this sudden BMS disconnect issue...perhaps a hybrid AGM/Lithium bank could address those issues, but it all seems to be getting incredibly complex...and not very clear as to how to manage it all....especially when not on the boat.

By contrast our 660Ah bank of AGMs has none of these issues - nor do we have the listing issue pointed out by a few, caused by the lack of mass of the Lithium bank.
Our system is simple to manage and has worked really well over 6 years. It is only just now starting to show slightly reduced capacity - but there's still plenty.
Mind you, we're not great fans of aircon, nor are we interested in having an induction cooktop, so our needs are relatively modest by what seem to be modern standards / requirements.

Also, sailing in remote parts of the Pacific, as we are want to do, brings up the constant issue - what do you do if it goes wrong? and that applies to everything on the boat.
Of course if you never stray far from your home port, or frequent the Western hemisphere only - and have plenty of money - then maybe these things are not an issue.
My aim has always been to be able to keep the boat going, wherever we are - that is essential for us.

Maybe I'm just  considered an old-fashioned sailor these days - certainly approaching the "old" part - there was a time when I was "ahead of the curve" on all this stuff, but that seems to have changed !

So, while I am impressed with the technological advances spoken of here and admire the courage of these early adopters, I now think that when the time comes, I will probably replace my old AGMs with new AGMs - for another 6 years...

Cheers
Alan
Elyse SM437

Addendum : and when I read things like this : https://nordkyndesign.com/charging-marine-lithium-battery-banks/
                     It makes the whole idea of Lithium even more scary and difficult to control..and while they say you will get many more years...will you really?