All batteries will ultimately fail, stop working, and cease to operate, and or otherwise end their useful life. It is the reality of a consumable product. The cost to operate a replacement battery in your device, however, is relatively cheap so it is not a catastrophe when batteries stop working (although certainly an inconvenience). Yet when batteries do fail have you ever wondered why?
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Common causes of battery failure include: battery degradation, warping, battery explosions, incompatible designs, improper hardware, battery misue and or abuse.