iBook G3 Battery Question

Recently my friend came into possession of a used iBook G3 (I don't know the specs off hand; but it runs Tiger okay), and ran into a slight problem. It appears as though the battery doesn't fully charge, and loses power 5 minutes after it being unplugged. I've looked at the battery, and it appears okay--although possibly lose. I'm sure that Apple wouldn't do repairs on it anymore, but does anyone know why the battery might not be working?

If specs are needed I can provide them. But its an iBook G3 running Tiger.

So there's really nothing that can be done; 'cause the battery is just too "new" for the machine itself? I kind of figured it was something just faulty about the machine itself. Thanks for the help.