Got a Wii Mote that is dead. The batteries have leaked inside of it...

This is one I acquired with a cheap system sold as spares/repairs on ebay yet it all works fine other than the Wii Mote.
I know they are only about £5 to buy new (3rd party), but is it worth opening up and seeing if it can be cleaned up and made to work or is it dead?

Anyone done it before?