Is ceramic (high heat resistant) something you can 3D print?
Ceramic was available several years ago, however the finished products were not up to my standards (too much variance in part thickness, too slow manufacturing times). However the new alternative is 3D printed porcelain which is even better than ceramic. The only catch is the porcelain parts are 3D printed as a negative mold, and then filled with liquid porcelain (then fired in a kiln with a glaze over the top).
There are quite a few limitations to working with 3D printed porcelain at this time, but it is doable. Feel free to PM me any ideas you may have, I'll tell you how feasible they are.
If you take suggestions, I'd like something like this
http://delta3dstudios.com/haze-can-case-5-cans/
but with space for a battery. In fact I already like the model, specially the fact that there is a place for the stem.
Hmmm, something that is doable. Although my concern would be the mouthpiece and can slots - due to the added height of the batteries, the mouthpiece and cans would rattle around, but I'm sure I could come up with something. I could absolutely build a custom case like this for you though, PM me if you'd like to place a custom order for one.