Science & TechHow it works
How your phone battery stores power: as migrating ions.
A lithium-ion battery has two electrodes, graphite and a metal oxide, separated by an electrolyte. While charging, lithium ions move into the graphite and tuck themselves between its carbon layers. While discharging, they travel back, and the electrons take the detour through your device. The invention won the 2019 Nobel Prize in Chemistry.
Useful: Batteries age least between 20 and 80 % charge and at moderate temperatures; sitting at 100 % all the time stresses the cells.
Source: en.wikipedia.org