Up to one-third more capacity than the standard system battery. This high-capacity battery has an extended area on the back edge & fits in the standard Think Pad Z60m system battery slot. It's design allows it to remain in the system when the system is connected to the Think Pad Advanced Dock, Advanced Mini-Dock or Essential Port Replicator. Battery life (and recharge times) depends on many factors including screen brightness, applications, features, power management, battery condition & other customer preferences. Lenovo 10.8V 9 Cell Lithium-Ion Battery for Think Pad Z Series IBM 10.8V 9 Cell Lithium-Ion Battery for Think Pad Z Series Up to 1/3 more capacity than the standard system battery to stay unplugged longer Up to 1/3 more capacity than the standard system battery to stay unplugged longer Original equipment specifications for correct fit & capabilities Original equipment specifications for correct fit & capabilities Backed by a Limited Warranty from Lenovo with renowned Service & Support available from IBM Backed by a Limited Warranty from Lenovo with renowned Service & Support available from IBM One year Customer Replaceable Unit One year Customer Replaceable Unit