Lenovo Battery Fifty Seven Plus ( 0C52863 ) Factory Sealed Lenovo Originals for T440p, T540p, W540, W541, L540 , L440 Lenovo 57+ 6 cell , Part Number : 0a52863 Is Pakaged In The Original Manufactures Factory Sealed Retail Packaging. ThinkPad Battery 57+ (6 Cell) standard system battery For L540, L440, T540P(Not for T540 Or T540S), T440P( Not For T440 or T440S), W540, W541. Lenovo 57+ Battery capacity (Amp-hour)5.2 Ah , Weight: 330 g (0.73 lb), Battery energy (Watt-hours): 57Wh. Battery Safeguard chip authenticates with Lenovo systems .Over-discharge protection to prolong the life of the battery. The battery lasts on average 57 watt hours* and utilises over-discharge protection to ensure a secure flow of power. Many factors affect battery life. These include: screen brightness, battery conditioning, features, applications, power management and other customer preferences.