According to the versus analysis of electrode reaction process between potential-controlled floatation equipment and metallurgical electrochemistry reaction unit, the distribution regularities of cell voltage among the electrodes of extra-potential-controlled floatation equipment has been achieved . Since the potential-controlled floatation equipment must provide suitable bubbles and channels for the flotation of mineral. The improvements of potential -controlled flotation equipment's efficiency have no choice but to choose an appropriate electrode material, In theory, this is the reason why the extra potential is more greater than the pulp potential.