Battery voltages, different in parallel
I'm having a stupid moment here. I'm trying to bottom balance my lithium cells so I hook them up in parallel. I left them like that for several days used to discharger to drain them down to 2.65 volts and then reinstalled them in my cart. To my surprise when I checked pack voltage it was still 50.1 which tells me I did not discharge all of them evenly or together.
So I went back and tested all cells individually some were at 2.7 others were at 3.1 and now they are way out of balance. So I hook them back up in parallel testing individual cells several of them are still at 3.1 and some are at 2.7 of course the full parallel voltage is a cell average. How long should it take a 270 amp hour 3.2 volt pack to balance? I also took the time to use my fluke and audible diode check across the full length of terminals to ensure I had good connections with the alligator clips.
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