Lithium-ion battery charging on an electrical vehicle is not terribly different from the charging process for your other electronic devices.
When you plug the car into a charger, the vehicle’s computer system analyzes the current to decide what is safe to put into the battery and for how long. The vehicle then receives the current, moving the lithium ions from the cathode to the anode. The chemical makeup of the battery allows a bigger current to go in without reactions taking place inside that could lead to a short circuit or fire.
High currents may cause irreversible changes over time. Some Tesla owners report that their range dropped slightly over time with regular supercharger use.