Why DC current is used to charge batteries, not AC?
DC current is used to charge batteries because batteries store DC power, and every time you charge your laptop, the charger converts the AC power from the grid into DC power for your laptop’s battery.
Direct current (DC) charging is faster because there is more power available and can provide up to 80% of your battery’s range within an hour for most vehicles.
AC charging is technically impossible. One way or another, batteries end up being charged using DC power.