Battery design
 

Hey guys, I am doing a project for a class i'm in. He let us choose out topics but we are required to model the heat transfer of whatever.
I decided to model an RC battery and try to figure out how hot the cells are for a certain battery case temperature.
I realize it can be hard to find out details about the batteries so it's going to be a rough approximation.

To do this, I could use some help with finding some details of the batteries since nobody would want to destroy a perfectly good battery.

-Does anyone know what the "foil" like material enclosing the cells is made of or how thick it is?
-How thick is the plastic case on most hardcase batteries and what kind of plastic is it?

I appreciate any help on this. There is a lot more that I could put into my calculations, but I'm probably just going to make assumptions to simplify it.