How do I install or remove the Battery Cover and Battery for my Samsung Galaxy S II?
You must fully charge the battery before using your device for the first time. A discharged battery fully recharges in approximately four hours.
Charging a Battery
Your device is powered by a rechargeable Li-ion battery. The Travel Charger used to charge the battery is included with your device. Use only Samsung-approved batteries and chargers.
Although you can use the device while the battery is charging, doing so will require additional charging time.
Install the Battery
Make sure the battery is properly installed before switching on the device.
Remove the back cover by inserting a fingernail or pointed object into the slot on the side of your device.
Lift the cover up and away from the device (2).
Insert the battery into the opening on the back of the device, making sure the contacts align (1). Gently press down to secure the battery (2).
Place the back cover onto the back of the device and press down.
Plug the USB connector into the charger/accessory jack on the bottom of your device.
Plug the AC adapter into an electrical outlet. Fully charging a battery may take up to four hours.