[H] Thinkpad T23 dying battery

[Winterlight]

My Thinkpad T23 Li-ion battery is dying. It lasts about 30 minutes.  I 
guess there is no way to "refresh" them, like a NICAD , is there?

First time I had a laptop battery go bad....these things are expensive... 
any suggestions on where to buy one?

 Any reason I shouldn't buy a generic on like this
http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLG,GGLG:2005-47,GGLG:en&q=Thinkpad+T23+Battery