Magic Trackpad stuck battery

I have a Magic Trackpad that sat unused in a work drawer for a few months. Like a total noob, I neglected to remove the batteries.

I recently reconfigured my workspace and decided to start using trackpad once more, but to my horror, the batteries had corroded and the one furthest in, is very very stuck.

I have tried a long neck, thin screwdriver to try and pry away some of the corrosion around the edge, and lot of banging/ knocking/ cursing, but the battery is still in place.

I welcome any suggestions on how I can remove the other battery and hopefully resurrect this trackpad into working order. I open to suggested chemicals/ power tools etc.

Many thanks in advance community!