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Which manufacturer is advising charging to 100% regularly to ‘balance cells’?

And how does that square with the fact that you can’t charge a BEV pack to 100% anyway, Tesla excepted?

Ergo, the BMS can balance at less than 100%.
At less than 99% all voltages are more or less the same across cells, so balancing is only effectively possible at 98-100% .
Not that would make any dent to the life of the battery if one cell is at 45% and the other at 46%
 

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otally up to the BMS des
cars dont get that "LOW" to see those differences.what your dash says as "0%" is like 10-15%, so from 15% to high 90s, your voltage difference between cells will be next to none.
Voltage difference is essential for fast and effective balancing, if you look into any lithium SOC graph and understand how an active balancer works, will be pretty obvious to you.
 

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Whether you ‘balance’ cells at 4.1v or 3.8v, doesn’t really matter, and my point was that BMSs have moved on in the last decade and they certainly can balance at different voltages.

Personally, I just think this is a subject that far too many EV owners worry about, and the way it’s often written about is just another little barrier to adoption for anybody reading about them on here for the first time.
My point is that at 99% one cell can be 100% and the other at 98%. which can be a difference in voltage of 0.4v or more.
At 50% one cell can be at 48% and another at 53% and the voltage difference between them will be 0.008v
Voltage difference is essential for balancing to work, and most BMS's will only do this at high state of charge for that same reason.
 
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