Can you leave your laptop charger on when fully charged?

Yes you can leave your laptop charger on once the battery is fully charged.

however, modern Li-Ion batteries should never be run ar full capacity continuously.

We recommend either removing the battery if you plan on using your laptop for a long period of time on the mains, or let the battery run down once a week and then recharge it again to keep the molecules moving within the battery.

See our simple guide here on how to care for your laptop battery