In more "general consumption" terms (because I am not an electric geek), could anyone explain why a specific cell in a LiFePO4 battery pack would go bad? I have two 1.5 year old packs made up of 8 cells each. They have probably been charged less than 30 times over the past year, properly charged after each use, proper temps in winter storage, etc. One pack seems fine but the other wasn't charging so we did the usual cell check. Each cell is supposed to be 3.2v. Three are basically dead. The other cells are OK. I know I need to replace the bad cells, but was curious why this might have happened.
Thanks for your help!