Electrochemical Treatment

Any process that involves the transfer of electrons between two substances—typically a solid and a liquid—and is either triggered by or accompanied by the movement of an electric current is known as an electrochemical reaction. In an electrochemical process, an oxidation-reduction (redox) reaction propels the movement of electrons from one molecule to another. When electrons move from an oxidised substance to a reduced one, a redox reaction takes place. The anode and the cathode are two conducting electrodes used in electrochemical cells. The electrode where oxidation takes place is known as the anode. The electrode on which reduction occurs is the cathode. Benefits include.
Materials that are inexpensive and non-toxic.

Drawbacks:
Cannot be recycled; may leak (weak acid electrolyte reacts with zinc)
short shelf life
unstable voltage