Hi duncan999,
The battery itself may be fine, as you stated the plastic piece broke it may not be making a good connection. If you could replace the clip it may work fine. You could try checking the manufacturer of the motherboard to see if they would have a replacement clip. The other options are, you can try online to find one, a computer shop or perhaps from another notebook. Here is a Google search page that may help you.cmos battery clip replacement google search. Please not the last link on the page, for battery clip. If you are unable to resolve this, the motherboard will require replacement.
