Giving the car a service and a once over. Found this;

http://i.imgur.com/D3dQB.jpg

Wanting to know how I stop these deposits forming on the battery terminal.

Thanks

If you want to clean it up, turn on the kettle (full) and pour the boiling water over to get rid of the corrossion. You can then sand all the metal lightly for a good clean, and then spray battery terminal protector over it which lasts between your services.

Also cover the terminals with vaseline after cleaning them with boiling water....

Also add bi carb soda to the mix as this will help disolve the corrosion

Well, I disconnected and cleaned the terminals and lugs with a battery terminal cleaner from Supercheap. Didn't use bi-card' or boiling water, but I did coat everything in some grease? that was included with a set of spark plug leads I bought a while ago. Looked like vaseline, had the word "dimethylpolysiloxane" on it. Big words = good stuff.... right?

Grease, vaso etc all good. Personally I use fish oil as it leaves a thin film with excellent anti corrosive properties.