Suppose AC current is shooting into a wire, and the wire is attached to a bulk piece of metal off to the side of it, kind of like a ground, but not as deep as a ground. Wouldn't the bulk piece of metal work kind of like a capacitor and smooth out the voltage a bit? Everywhere I Google, I see the same definition of capacitor, which says it has to have a dielectric between two plates. I want a 1000uf 50V non-polarized capacity, but can't find one for sale anywhere. So I want to build my own. I'm having trouble finding any equations for electron electron repulsion in a fixed area of Culombs, stuck in the area by a voltage. I'm designing a battery charger, and want to use some capacitors to help smooth the voltage.