Mathematical models of current losses in bipolar cells

Abstract

A thorough study of current losses in bipolar cells has been made for the development of the great energy-saving potential of bipolar cells. A proper equivalent circuit for bipolar cells has been proposed, and mathematical methods for computing current losses for all types of polar-ization have been developed. For linear polarization, the current losses can be computed by solving either a tridiagonal matrix or a second-order ordinary differential equation. These values can be used to evaluate the minimum current losses at given conditions. For other kinds of polarization, the current losses can be computed by similar methods if the necessary experiments of measuring the cell voltages of each electrolytic compartment have been made. These values can be used to design practical bipolar cells. Extensive experiments have been made to evaluate the effects of electrode polarization, electromotive force (emf) of the galvanic cell for the for-mation of electrolyzed substance, gaseous products, geometric dimensions of electrolytic cells, specific resistance of electrolyte used, and the total and ordinal number of electrolytic com-partments on current losses. This was the first time such systematic experimental research had been undertaken. Experiments showed that theoretical models were in good agreement with measured data and that DC energy consumption of 0.45 kwh/kg Pb for lead electrolysis from molten chlorides could be achieved in a cell with seven bipolar electrodes.