Originally Posted by
Mooncatt Once in a while, running a battery down to the cutoff is ok and is part of the calibration process if that's ever needed. Doing it all the time,, yes that will kill a battery quicker.
There is no calibration process. That a myth that comes from old nickel metal hydride (NiMH) batteries, and doesn't apply to lithium ion (Li-ion) batteries that are used in today's smartphones. Li-ion batteries don't need to be calibrated.
Draining a Li-ion battery all the way will cause damage. Fortunately, your phone operating system prevents that (when it says 0% and the phone shuts off, it's not actually at 0%).But if you were told force it by repeatedly booting the phone until it won't boot anymore, then you'd be causing damage.