ThinkPad Battery 82 (4 cell, 32Wh) (4X50M33573) The 4-cell ThinkPad battery 82 is a replacement/spare battery for ThinkPad new E-series system. The battery is rechargeable and can be used as replacement or as a convenient spare for ThinkPad E570, E570c & E575 systems. This battery is powered by Lithium-Ion technology and has a safeguard chip which authenticates with Lenovo systems. The battery lasts on average 32 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.Feature: Lithium-ion technology 4 cell Polymer flat battery Over-discharge protection to prolong the life of the battery Battery energy (Watt-hours): 32Wh Battery Safeguard chip authenticates with Lenovo systems