Primary cell dioxide is used in the Leclanché cell and zinc–carbon cell, and nitric acid is used in the Bunsen cell and Grove cell. Attempts have been made to make simple cells self-depolarizing by roughening the surface of the copper plate to facilitate the detachment of hydrogen bubbles with little success. Electrochemical depolarization exchanges the hydrogen for a metal, such as copper (e.g., Daniell cell), or silver (e.g., Silver-oxide cell).so called The battery terminal (electrode) that develops a positive voltage polarity (the carbon electrode in a dry cell) is called the cathode and the electrode with a negative polarity (zinc in a
Standard electrode potential 0.00 V and any electrode, for which the electrode potential is not yet known, can be paired with SHE—to form a galvanic cell—and the galvanic cell potential gives the unknown electrode's potential. Using this process, any electrode with an unknown potential can be paired with either the SHE or another electrode for which the potential has already been derived and that unknown value can be established. Since the electrode potentials are conventionally defined as reduction potentials, the sign of the potential for the metal electrode being oxidized must be reversed when calculating the overall cell potential. Note that the electrode