STRUCTURE AND PERFORMANCE OF SINTERED IRON ELECTRODES

The discharge capacity of an electrode prepared by the sintering of sponge iron powder has been found to be highly dependent upon the electrode's density. Maximum capacities (near 0.4 Ahr g-1) have been determined for electrodes having densities within the range from 21.5 to 23.5% of the theoretical density of iron. High capacity was also found to be favored by low charge current density (25 mA cm-2. The capacity of a low density electrode (19.6% of the theoretical density of iron) was found to be much less affected by discharge current density than were higher density electrodes. Charge and discharge potentials were also determined as a function of electrode density. Large (400 cm2) electrodes of the optimum density were prepared and found to have the same large capacity as their smaller, test-size counterparts. © 1979.