djmp69

I was just given a 50c 5000 6s lipo today. When I put it on the tester, it showed 4%, 21+ volts. Red flag in my book. So I asked the guy when the last time he stored it or had it on a charger. He said August. To me, that's alarming, but I figured I'd try it anyway. I'm just wondering if there are things I should be looking for while I'm charging it, or is it even worth charging? Is it too far gone? Any special procedure I should do to make sure it's ok? My plan is to charge it, make sure the cells balance ok, then discharge it and watch the voltages. Not sure at what rate I should discharge it for a reliable test, any suggestions? I really have a gut feeling that I should pass on it, but if I'm being overly cautious and this battery could possibly be saved or be ok, then cool.

Any ideas?

mushia

The recommended cut off voltage is 3.7V per cell.

djmp69

Right, I know that, and that's my point. At an average of 3.48 to 3.50v per cell, is it past the point of no return, or does it depend on if the cells went into deep discharge? How hard and firm is the 3.7 volt floor rule? I'm charging it now, and it seems to be ok, so I'm going to have to wait and see how well it stores/discharges

djmp69

UPDATE: Solved. Battery is trashed. It only charged to 22.83 volts. Cells all balanced out at 3.80/1, but it won't go any higher. Question answered, battery going bye bye!