Originally Posted by
ploves27
Okay so I rebuilt them as side by side packs and tested them again. I put them on the charger until 2 of the cells got hot (around 135 degrees). I'm guessing those are the bad cells but they had the same voltage as the other cells 1.39 volts. I guess I'm going to find the best cells of the two packs and try to make atleast one good one.
Thanks for the help guys!
Before you go mixing cells on your packs balance discharge them (which you can do now that they're side by side), and drop all the cells down to the same voltage (using a discharge tray) then charge them back up! It will only take a little extra time, and could save you from having to chuck batteries that may still be good. If they're still doing it, then ya, bad cell
Also, I would _not_ mix cells between manufacturers even if they are the same mAh rating, unless it was a last-ditch effort. Even cells from the same manufacturer within two different packs can be different enough to cause you headaches.