Smartphone charging myths – Are you killing your battery?
Nothing is cast in concrete but the consensus seems to be "It is important to note that the durability and capacity decay of the lithium-ion batteries used in smartphones are measured in cycles, which consist of full 0-100% discharges and recharges".
"If you want your battery to last as many cycles as it can before it degrades, experts recommend constantly keeping the device above 50%, but below 80%, turning it off when charging, and never allowing it to deplete fully or to become fully charged."
The complete discharge myth was a truth back in the days of Ni-Cd batteries which developed memory problems. The reality is it is often difficult to know when to disconnect your phone at around 80% unless you use an app like AccuBattery to warn you, or if your phone is rooted you could try an app that stops charging at a predetermined percentage like https://forum.xda-developers.com/android/apps-games/root-battery-charge-limit-t3557002.
|Smartphone charging myths – Are you killing your battery?
We examined evidence and expert opinions to determine if any “charging myths” have merit.