So I recently made a 10s5p Pack, and now it will not charge past 39.5 volts.
I have checked the voltage at every single one of the 50 cells, and every cell reads 3.95 volts exactly.
I’ve done some reading, and found that the reason the charger might quit, is because one cell group might read 4.2 volts across, so the charger will shut off. However, none of my groups are at 4.2 volts, They are all at 3.95.
I am at a loss for what could be preventing the pack from reaching a higher voltage…
I mean I did go for a really long ride, to completely discharge the pack. I brought the whole pack down to 31 volts, and then got home, and right away brought it back up to 42 volts. However the next day (yesterday) It suddenly will not charge past 85% or 39.5 volts.
Did you ever short anything while installing the BMS? It’s very easy to short something out when installing BMS it could happen to anyone and that would be enough to damage it.
I agree with @Battosaii, it sounds like an issue with one of the balance channels on the BMS which typically only happen when a channel cap has been burnt out.
I would temp install a charge port on the packs main positive & negative and attempt to charge the pack to full. If it gets pretty close to 4.2 per cell then turn off the charger and replace the BMS. If it doesn’t then your issue is somewhere else.
When you say, “a channel cap has been burnt out.” Is that referencing to the JST plug(male/female) or something directly soldered onto the PCB of the BMS?