I've got this exact same thing happening to a 3s truerc pack i got last week.. cell 1 is always lower than 2 and 3.. I balance before charging, and when I take it of the charger cell 1 is low by ~.05v.. I can't balance while charging because I'm using astroflight's. when I first got the pack, cell 1 was chillin at 2.5v.. the others were around 3.5v.. I just slowly charged at 1/2 - 1C until the pack was 1/2 charged, took it off and balanced, then continued charging at 2C. so far the pack's been running great, I dunno how long it'll last though w/ that one cell.. I'm not sure how many amps i'm pulling, but the pack's only rated to 80amps =\.
ok just charge the pack, during charging, it,s the cell 2 (the one who,s lower normally) that was the higher during charge but not too much, about 0.017 v of gap.
I,am thinking that this cell have a lower internal resistance and discharge and charge faster than two others one.
I've got this exact same thing happening to a 3s truerc pack i got last week.. cell 1 is always lower than 2 and 3.. I balance before charging, and when I take it of the charger cell 1 is low by ~.05v.. I can't balance while charging because I'm using astroflight's. when I first got the pack, cell 1 was chillin at 2.5v.. the others were around 3.5v.. I just slowly charged at 1/2 - 1C until the pack was 1/2 charged, took it off and balanced, then continued charging at 2C. so far the pack's been running great, I dunno how long it'll last though w/ that one cell.. I'm not sure how many amps i'm pulling, but the pack's only rated to 80amps =\.
Balancing before charging isn't going to help an end-of-the-charge imbalance, it will only make it worse. That is, unless your pack is made up of cells perfectly matched for capacity .
Wait, why can't you balance while charging?
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