I don’t want to hijack @SycloneDriver’s post, but this is AlFP system related, so hopefully not egregious… if I should start a new thread, please comment,
I was checking my new Humseink LifePo4 batteries today after the batteries have been on the charger for a few days. Batt 1 showed 100% SOC and Batt 2 showed 99%. Interestingly, the BMS on Batt 1 shut off the charging switch. I assume since it was at 100% and couldn’t accept any more charge. The batteries are paralleled (see photo below).
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I went out for a 2.5 hour sail today, with a light load on the house bank (fridge, VHF, stereo, CP & instruments).
When I got back, I left the charger off until I could check the BMS for the 2 batteries. Now, Batt 1 still showed 100% SOC and batt 2 was at 86% SOC.
I am not sure why these batteries, if wired in parallel, would not supply power to the house system in equal measure. Instead, it seems that one battery is doing all of the work
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I have written to Humseink to see what they can tell me (if anything). I have discovered that their BMS app will not let me see what the individual cells are doing

. They did say that their engineers are working on an upgrade to the app.
So, here is a crude drawing of my DC system (left out the AC side of the equation for now)...and only the house side. Left off the starter battery, switch, charger, etc for that.
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Does anyone see anything blatantly wrong with this set up (I hope not, as I have sailed with it a few times now). Or could this just an issue with the batteries? One thing I could try is to install a positive and negative bus bars and hook each battery individuslly to the bus bars. But the charger would charge the bus bars (single output charger ). Not sure that changes things much. Does paralleling LFP batteries need to be different than FLA?
Greg