Stay unplugged longer with the help of a spare or replacement Think Pad system battery. Replace your original 4-cell system battery (select models) or carry an extra to extend your unplugged computing time. Its compatible design allows it to be in the system when the system is connected to Think Pad X200 Ultra Base. Features Lenovo Lithium-Ion Battery for Think Pad X200 Tablet series Lithium-Ion (Li-Ion) technology Four-cell, rechargeable system battery, 14.4 V, 2.0 Ah Standard system battery specifications Over-discharge protection