There is no such thing as "100%" or "60%" or any other battery meter number. They are all guesstimates based on the battery's history and cycle count. Li-ion b

There is no such thing as "100%" or "60%" or any other battery meter number. They are all guesstimates based on the battery's history and cycle count. Li-ion batteries don't have a simple voltage-charge relationship like lead-acid batteries do so you can't actually know the real charge state of the battery (and even those have a number of ways the battery chemistry can get messed up). I'll also note that your specific battery history matters a lot. If you leave your phone on a hot car dash in the summer even once it will dramatically alter that battery's performance. It isn't as simple as saying it cuts the lifetime... the battery's ability to deliver peak current is affected.