60-80%

I read a couple of articles that today’s batteries in digital devices like tablets and phones last longer if they are charged to 60 or 80%.  I wondered how much longer and saw an estimate of twice as long.  To me, that is enough to matter.

I have found that charging Apple phones and tablets goes faster when I turn a device on, plug it up, see that it is charging and turn it off, still plugged in.