Hi maybe this is stupid question, recently bought eve280ah v3 cells. 24v system. Attached to cell 5 and 6 wire to feed my esp32. But when those 2 cells once hit bottom and bms cut the output then i just bought usb pcb and now feed it with first ant last cell (whole pack feeds energy to usb). And when first charged those 2 cells were lower than others. All seems logic, those were depleted the most.. ok.. Then had to use battery and discharged it bellow the level those 2 lower voltage cells were and all cells became equal (~ 3.31v, delta was about 0.003v). Than when cheap electricity was available i started to charge them. All looked nice, balanced..at least till 3.41v and then suddenly those 2 cells started to drop voltage while others get higher voltage. See picture it shows 1 cells that was lower and other that was like rest of the 6 cells.. HOW this is possible??
How can voltage drop while charging? Is this because of other 6 cells have much lower capacity? Why it was ok till 3.41v and sudden started to drop.
This is with 2 cells as i mentioned, but picture only 1 low and 1 'normal' to make it cleaner.
PS. also when stopped charging (6 cells were at 3.5v and current about 2A.. - used voltage limit @28v so amps dropped) and started to use battery, now the lowest cells still are higher voltage than those who seemed to be more charged. Is this just unbalanced cells problems (both x-files)?

How can voltage drop while charging? Is this because of other 6 cells have much lower capacity? Why it was ok till 3.41v and sudden started to drop.
This is with 2 cells as i mentioned, but picture only 1 low and 1 'normal' to make it cleaner.
PS. also when stopped charging (6 cells were at 3.5v and current about 2A.. - used voltage limit @28v so amps dropped) and started to use battery, now the lowest cells still are higher voltage than those who seemed to be more charged. Is this just unbalanced cells problems (both x-files)?

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