Samsung SGH-S959ZKATFN - Manual (Page 13)

Getting Started 9
3. Press along the edge of the back cover (3) until you have a
secure seal.
Note: Make sure the battery is properly installed before switching
on the phone.
Charging a Battery
Your device is powered by a rechargeable Li-ion battery. The
Travel Charger that is used to charge the battery, is included with
your device. Use only Samsung-approved batteries and chargers.
Note: Long backlight settings, searching for service, vibrate mode,
web browser use, and other variables may reduce the
battery’s talk and standby times.
Although you can use the phone while the battery is charging,
doing so will require additional charging time.
Note: You must fully charge the battery before using your phone
for the first time. A discharged battery recharges fully in
approximately 4 hours.