I tried to clean as much as I could, some contacts were broken due to corrosion. I couldn't clean everything.

Also found a small amount of that blue stuff on a chip near the battery compartment, I didn't want to touch it to avoid damage. Leaving that there will damage the PowerBook?

Is there any way to cover the empty battery compartment?

I don't want to put the old battery that caused all the mess. It wouldn't make sense to buy a new battery because I wouldn't be able to use it since some contacts are broken.

Thanks for your help