I've found a way to restore partially the duration of the battery of my iBook. It used to last 1hr 30m. Now it lasts more than two hours. Here's how I did it. Work normally using the battery. Wait for the warning about the battery. Open a terminal, you must be an admin user. Type:
% sudo shutdown nowThe password required is that of your account. At the end of shutdown you are in single user mode. Now you can wait until the battery will completely be discharged. You can accelerate the process typing fsck repeatedly.
Mac OS X Hints
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