The Samsung Galaxy Z Fold 3 and the Samsung Galaxy Z Flip 3 have a charging limit feature that’s designed to protect your battery.
Smartphones are built to last, though lithium-ion batteries are still chemically degrading from the moment they are first used. This is a result of the fundamental chemistry behind how these batteries work, but there are ways to slow the process down. Not charging your phone to 100% every time you charge it is one such way, and it’s often recommended to charge your phone to around 80%-85% for the best battery longevity. The Samsung Galaxy Z Fold 3 and the Samsung Galaxy Z Flip 3 are getting Samsung’s “protect battery” feature that prevents charging above 85% when enabled.
