FlexiBMS - battery not charging over 80 percent (second one now, different type)

Hi there, I’m having some trouble charging recently. It didn’t do that in the beginning but started after a few months. It goes to around 80 percent then then stops. If I unplug it and plug it back in it sometimes does the full charge. Recently it starts to be more and more on and off though. I had the same issue on an older board. In that case I used a different charger and it seemed to work. But before I buy the NEXT charger I was wondering if it could have other causes.
my thoughts were:
firmware and FlexiBMS settings???
cabeling? how important is it and why that balance cables don’t touch/cross? Or is it at all?
Doesn’t seem to be heat related.
Not sure how to troubleshoot that.
Grateful for any input.


Measure the voltage coming out of the charger with a volt meter

Read the states of charge off of each cell based on the BMS

Report back to us

thanks. the bms isn’t hooked up to anything that could read it. i could only measure each cell. currently got the flexibms for the small form factor

You’ll want to check them by hand then, if a cell is way off it won’t let the system finish charging

If you’re connected to the ecs CAN and have a BT module, Freesk8 App should allow you to see cell readout

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