On how to recharge your batteries, the results are more in line with our expectations. Thus, you are 60% to recharge your mobile as soon as the battery is less than 20%, which is a good reflex to limit wear. Indeed, as Olivier Simon explains, batteries degrade more quickly when the voltage is very high (charge level above 90%) or very low (below 20%). It is therefore preferable to multiply short charging cycles rather than letting your smartphone discharge completely.
Conversely, leaving your mobile plugged into a power outlet when it is at 100% battery will gradually degrade your battery. In question, “small overvoltages applied by the charger to the battery, which is already at its maximum voltage to maintain the level”, specifies Olivier Simon. These overvoltages affect the quality of the battery, whether you charge your smartphone in wired mode or by induction. Also note that it is better to charge a cold battery and, on the contrary, to use your smartphone at the right temperature.