how to make a (cheap) battery

Ok so there are many ways to do this but here's the basics. A battery as we all know facilitates electrical current. The battery does this usually using an acid, which allows the copper to steal electrons from zinc or lead. This happens because of the metals' difference in electronegativity, and the movement of the electrons is what we call and use as electric current. so to make a battery all you need to do is submerge plates of metal with contrasting electronegetivities in an acid, and complete the circuit so the electrons can move from plate to plate (according to their electronegativities), then place what you want the current going through in between.