Get on over to Radio Shack (or whatever equivalent electronics toy store may be near you). They usually have battery cases for AA and AAA size batteries, and they have all of the necessart contacts to hold the batteries and small diameter wires to connect them.
As for connecting to the foil, I doubt theat Bare Metal Foil™ will take much soldering, so: at the end of the foil, wash off the adhesive with acetone, then fold it back on itself several times to make a substantial tab. Poke a hole through the tab and mechanically attach it to the wiring with OO or smaller brass screws and nuts.