In this case, [Mika] wanted to resurrect the battery from his IBM Thinkpad T40. He identified the offending cell and replaced it, but couldn’t get any juice out of the battery after the repair.

The ThinkPad was created in 1992 by IBM. In the first few years of development, three product lines came to the forefront. The 300 series ThinkPad was the bottom rung, the 500 series was middle of ...