Hi Jayne, on the front of the battery pack is a rectangular red button. Press and hold this down whilst sliding the battery pack away from the base of the drill. To charge the battery, insert the charging lead into the socket on the battery, then plug the charger into the 13A wall socket and switch on. The LED will be RED if the battery is low on voltage and whilst being charged and then change to GREEN when fully charged. Once fully charged, slide the battery back onto the base of the drill until you hear a click, then it is correctly installed.