Originally Posted by 4S4K4N

So after a good days worth of racing I packed up and went home. I didn't get home until late so I decided I would recharge my packs in the morning. This morning I hooked my TrakPower 2S pack to the charger and to my surprise one cell had dropped to 2.5V. The other was perfectly fine at 3.4V.

I know your not supposed to let LiPo's sit fully discharged, and it wasn't fully discharged. I never hit the LVC, although i probably got close to hitting the LVC so maybe that point is moot. So after I set the charger to NiMH mode and set it to under 1 amp and after about 30 seconds to a minute the second cell reported 3.4V just like the first one. Now I'm charging in LiPo mode at 1A which is around 1/5C on this pack.

Should I consider this to be a defect in my pack or just a result of me letting the pack sit overnight almost at the LVC? This is pretty much a brand new pack with only 5 or so charges through it.

And just as a disclaimer... I'm not new to this. I fully know the dangers of trying to recharge a cell under 3V. I've done this exact process a few times on packs that I accidentally ran down too far. I'm not asking whether it's safe or not. I know the risk that I'm taking and I am surely keeping a very close eye on the pack as it charges.

What I’m concerned about is that a single cell became so unbalanced and went so low overnight on it's own behalf. It was not plugged into the car during this time, and the pack itself never went below 6.4V while running. It was just stored overnight at a voltage of probably around 6.6V if i had to guess.