GoKawiilCNET battery experts advise avoiding 100% charges and overnight charging
CNET reports that keeping a phone's lithium-ion battery at full charge for extended periods, as happens with overnight charging, accelerates capacity loss through voltage stress and heat. Fast charging and gaming while plugged in also generate heat that speeds up battery wear, while deep discharges to 0% add further strain. The outlet says these effects compound over time, becoming measurable within a year and obvious after two.