I have a high end charger and constantly am vigilant that my cells are balanced.I had left a pair of these batteries stored at 3.8v per cell for 2 weeks. I came back to discover one battery had 4 cells below 1v.I tried to recover the battery but so far it doesn't seem likely.I can't be certain I that I was at fault for the issue, I might have missed something. But in my opinion I treated these batteries very well and have experienced an unfortunate issue.I had my battery for 10 weeks and have charged it about 15 times.
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