Balance question

[tetonmtnbiker]

Hello,

I have 2 sets of 4 Fortune 100 amp hour cells. And 2 overkill solar 120 amp BMS’s. While I was in the flat part of the curve charging My cells were at most .003V apart (3mV)! At the very end of the curve when my first cell reached 3.65 V, they were 29 mV apart. I was going to top balance them, but with them being so close together would you bother?

Thanks,

Jeff

 

[Pierre]

Hello,

I have 2 sets of 4 Fortune 100 amp hour cells. And 2 overkill solar 120 amp BMS’s. While I was in the flat part of the curve charging My cells were at most .003V apart (3mV)! At the very end of the curve when my first cell reached 3.65 V, they were 29 mV apart. I was going to top balance them, but with them being so close together would you bother?

Thanks,

Jeff

No.

 

[tetonmtnbiker]

2nd battery had a delta of .003 between highest and lowest cell during the flat part of the charging curve and a .046 Delta when the first cell reached 3.650 (lowest at 3.604). I’m still thinking ? don’t bother top balancing. Still agree?

 

[Craig]

2nd battery had a delta of .003 between highest and lowest cell during the flat part of the charging curve and a .046 Delta when the first cell reached 3.650 (lowest at 3.604). I’m still thinking ? don’t bother top balancing. Still agree?

Agree we also talked about this elsewhere. Probably best not to charge them that high anyhow for lifespan purposes

 

[Pierre]

2nd battery had a delta of .003 between highest and lowest cell during the flat part of the charging curve and a .046 Delta when the first cell reached 3.650 (lowest at 3.604). I’m still thinking ? don’t bother top balancing. Still agree?

Yes. Cells delta V of up to about 80mV at the extreme ends (In my book) should be quite acceptable.