Heat will work on epoxy, but will not have any effect on CA (in my experience). Debonder works good, and doesn't smell as bad as acetone, but I think acetone works the best. Just be careful with it. Put a little on the glue, and let it sit for a few minutes, and then carefuly start rocking the battery back and forth. A second application may be necessary. The glue will eventually soften up and you can remove the battery.

It seemed like a good idea at the time, didn't it? I usually just box my batteries in with scrap balsa strips (1/8 inch thickness). It's easy to cut those sticks off when you need to remove the battery.