Weird battery balance issues with setup

[Samhall72]

Hi eveeyons, new to the forum after reading alot on here through googling.

I am having issues with my power setup in my camper that j just can't work out.

I have 2x batteries in parallel, each one is 105ah lifepo4 12v, with its Own daly 4s 12v 100a bms.

The batteries live in a single case and are paralleled internally at the bms for negative and battery terminal for positve lines.

I am having the following issues:
Keep getting cell 4 of pack 1 going out of balance and shutting bms charge side down. The bms of pack one also wuite often wont display the current charge or discharge. It also seems to go to sleep ans becomes non contactable by bluetooth even when there is still load.

Pack 2 is more reliable, but keep getting cells 2 a 3 going out od balance from 1 and 4.


I csnt help feeling that this is a bms and wiring issue. The packs seemed.when they were assmebled and balanced and charged before paralleling.

I assumed that as long as the packs were same spex and bms were the same With the same settings it should work. But apparently not.

Hellllllllp im. Going a bit mad here.

Thanks,

Sam

 

[NVS]

Put a 5amp active balancer on each battery and you'll be amazed by how well they stay balanced. Google helwig 5amp active balancer helwig seems to be the preferred brand. Also check all of your connections especially the little sense wires make sure all the crimps are good.

 

[JeepDaddy]

Welcome to the forum.

Did you top-balance your cells?