The battery is a rechargeable lithium-ion type and provides up to 8 hours of use on one charge. It only takes roughly one hour to charge it, and it can be recharged approximately 1,000 times. The battery is inserted into the bottom of the drill. There is a black arrow on the battery between the two green release buttons. Line that arrow up with the arrow on the bottom of the screwdriver. Insert the battery by pushing it in, until one hears a click. The charging unit shows the battery’s charging status via an LED display. A green light indicates full charge, red means no charge, and both red and green lights simultaneously indicate a half charge. Please note that due to the battery being lithium-ion, Phoenix Contact can only ship it via ground.