T400 not charging - Battery damage?

[Ragueneau]

I recently took my T400 in to a repair depot to have my keyboard replaced under ThinkPlus. At the time, my 9-cell battery was at about 70% of its total life, or about 3.5 hours of runtime. I got the machine back and ran it from the dock for the next week, and I started to notice the battery light was blinking, although I didn't pay it much attention.

This weekend I undocked it to bring to a friend's house, and the battery was completely dead, and refused to charge. Power Manager says 'the battery has failed due to normal wear', that it cannot be charged and must be replaced.

I tried removing the battery and holding down power for 30 seconds, but no change. I also looked into the event viewer, and it seems that the repair depot only had the machine powered on for about five minutes while the work was done.

What could have happened to my battery? Can it be reversed?

Will my Thinkpad Protection cover a new battery since it wasn't slow degradation over time?

[richk]

It sounds like the battery is just dead. Battery warranty is one year, whether or not you have thinkpad protection.

[Ragueneau]

Do batteries die that radically that quickly though?

[richk]

Unfortunately, yes. However, it would be best if you had another machine to test it in

[redhook]

Do batteries die that radically that quickly though?

Lithium-ion batteries have a protection circuit in them that will not allow the battery to charge once all the charge cycles have been completed. They just die.