Batteries & Magnets

[Galvatron]

I was having fun with my pocket compass one day and observed that the needle reacts to AA batteries as if they are magnetized. I looked around and found a couple things

Any thoughts on if this magnetism is because of the charge or because of the parts the battery is made of. I also wondered if the effect has been measured.

I thought that it would be cool to take advantage of a batteries energy in a different way so as to not run it down so fast.