Steampunk Bunsen Battery

How does one power an Aperture Science Handheld Portal Device, you may ask? With this...

Ok... technically steampunk should be 'steam' powered, but when I was making my Portal Gun I had my heart set on a charging-based system as it is a 'portable device' after all.
So this is loosely based on a Bunsen Battery, which is a type of Galvanic Cell/ Electrolysis kind of thing. Apologies for the vagueness but science isn't really my field of expertise!

The connection is actually an old TV aerial cable in disguise which fits into a cleverly built in socket on the gun itself! I'm not sure why I do these things as literally no one notices unless I point it out... but it makes me happy on the inside

P.S. Hand is for size comparison to show the diddyness!