Stay unplugged longer with Think Pad Battery 29 (4 cell), Think Pad Battery 29+ (6 cell) & Think Pad Battery 29++ (9 cell). These rechargeable batteries use Lithium-Ion (Li-Ion) technology & can be used as replacement for aging system batteries or as a convenient spare battery. Features & Benefits: Lithium-Ion (Li-Ion) technology Six-cell, rechargeable system battery, 63 Wh Standard system battery specifications Over-discharge protection Capacity: 5600 m Ah Voltage: 11.1 V Compatible with: Think Pad X220
Dimensions Width 208.75 mm Depth 55.08 mm Height 22.79 mm