This has happened to everybody at one time or another - contacts on battery-powered things corroded by leaking batteries. I have an Olympus 'dictaphone'-style digital voice recorder. It uses 2 AAA batteries, but the batteries in mine have leaked slightly and corroded the contacts at the -ve end, resulting in poor conductivity and difficulty in getting the thing to switch on. The contacts are little springs and thus rather hard to clean with anything abrasive.
Can anyone recommend anything that'll clean the contacts and restore conductivity or is it a lost cause?