ThinkPad T series T420s, and the T520, have been lauded for their battery life – up to 30 hours with a 9-cell battery slice. ThinkPad T series The ThinkPad T series is a line of laptop computers introduced by IBM in 2000. After the transfer of the consumer computer division in 2005, they were developed and marketed by Chinese technology company Lenovo. IBM introduced the T series as part of their ThinkPad brand in 2000. The laptop was meant to cater to users working with multiple networks and in different environments. This resulted in the development of the IBM Embedded Security Subsystem. From
ThinkPad X series Windows 7 Enterprise. The specifications<ref name="Notebook Review - Lenovo ThinkPad X201/X201s Review"></ref> of the X201 are given below: The specifications of the X201s are given below: The X201 tablet, released in 2010, was criticized by Engadget for its lack of durability, protruding battery, and thick body, while praised for its performance. Notebook Review had similar views about the X201 tablet in terms of both performance and battery life while indicating that the display was superior to that of the X201 or X201s. The ThinkPad X-series laptops released in 2011 by Lenovo were the X120e, X220, X220i, X220 tablet and X1.