How do I fix an electric bicycle battery that is out of cell balance?
crwdns2934249:0crwdne2934249:0:
Problem/error occurring
The lithium-ion battery (NKY451B02B Panasonic 25.2V, 13.2Ah) in my electric bicycle is out of cell balance and inoperable.
What I tried by myself
I disassembled it and found that there are 42 cells (18650) (6 in parallel and 7 in series configuration). The specification of one cell is estimated to be 3.6V, 2200mAh. When I measured the voltage for each block of six parallel cells, six were 3.81V and one block was 0.3V. One of the cells had rust on it, so it was removed. A cell (18650) that was used in a mobile battery was mounted in its place. We then charged the cells to an equivalent voltage, but the cell balance was not resolved.
I assumed that the control board was memorizing the cell balance status. I would like to know how to resolve this condition.