Hi happy users of addapto!
I’m also the happy daily user of a mini-e addapto for now 3 years to go to work. I have made a battery (20S5P) 6 months ago which used to work also perfectly thanks to the very good information I’ve found on this forum. Thanks again everyone for that. But I’ve now experienced the following issue 1 week ago for which I would need your help if possible:
-after a charge every cell was balanced excepted one which was lower (25mV) cf. picture below (for the second time with 65mV). Usually the gap is only less than 8mV possibly 2mV.

-But when I did use the bike 10mns later this cell was higher than the others (30mV) and above the maximum charging Voltage
When using the bike, the Voltage gap remained constant even when pushing the throttle. And the following charge was OK but the failed cell has needed to be balanced for a while.
This makes me think that the cell works correctly as its behaviour during charge and discharge and its internal resistance seems OK. So my personal hypothesis is that there was an issue with the cell voltage measurement which remained wrongly fixed. So every cell went up during charge but only the others were balanced. This could explain why the voltage was lower for this cell at the end of the balancing and but higher than the target when using the bike after that. I have to say that my battery is sealed with silicone and cells are compressed by the case to make the connection. So the troubleshooting is not so easy as it takes me quite a long time to open and close the case to access everything. The other issue is I have to use it to go to work.

I do suspect either a bad connection issue or a problem with the BMS (SW or HW?) but I’m not sure this could explain this behaviour.
After that everything went fine again for one week but I experienced the same issue this morning with a bigger voltage gap (65mV) which changes quickly to 150mV. This gap remains quite constant during bike use but the measurement seems less stable than the other cells.

Here are my questions:

-Did anyone experienced the same issue or would have any hypothesis?
My other question related to the troubleshooting is:

-The failed cell is the 4/20. Is it possible to renumber the board (7,1,2,3,4,5,6) and not to use anymore the 1st board (the 7 after the previous renumbering) as I only use 5 boards for my 20S. It seems to be possible when reading the manual but I did not figure how when using the menu (cf. picture below), I use the buttons but nothing happen. If the issue comes from this particular board this would solve this issue.
Thanks in advance.
Jerome