All you have to do is google "fix laptop battery" (without the quotes) and you can get stuff like this:
http://www.fonerbooks.com/laptop_3.htm
-Short condensed version of what you have to do with any battery.
http://www.electronics-lab.com/articles/Li_Ion_reconstruct...
-Very good and long step-by-step guide.
http://www.engadget.com/2005/06/28/how-to-rebuild-your-lap...
-(same battery as second link but condensed with user comments)
http://www.schou.dk/linux/laptop/
-A fix in a nutshell.
http://www.hackaday.com/2005/08/26/how-to-laptop-resurrect...
-Scroll down a little to "Battery Revival" and it shows you how to bring back the battery to life with the use of a freezer.
http://repair4laptop.org/notebook_battery.html
-Website with many links that will probably help you.
http://consumerist.com/2007/02/dell-dead-battery-suffers-from-temporary-battery-failure.html
Exercise regularly battery
This is recommended for those using the AC adapter for longer period of time. We recommend using the battery at least once in two weeks apart.