Report on Heat Balance Studies on Submarine Storage Cells

Heat balance studies have been made on WLH-29 Ironclad cell to determine the magnitude of all heating and cooling effects and to determine the effect of these magnitudes on cell temperature both in the free electrolyte above the elements and at various other locations in the cell. The studies include a complete survey of the cooling effects associated with cell ventilation. It has been found that the main sources of heat in the early stages of the charge are the reversible heat effect of the charging reaction and the irreversible heat due to the I2R drop in the cell. During the latter stages of the charge when gassing is pronounced, the main source of heat is due to the heat formation of molecular hydrogen and oxygen from the atomic gas produced from the current. Ventilating air is not an important factor in reducing cell temperatures, either from the standpoint of evaporation or direct conductance. The reversible heat effect of the gassing reaction is an important cooling effect during the gassing phase of the charge. There is little temperature change from place to place in the cell during charge. The small temperature difference found in the early stages of the charge disappears when gassing sets in. This equalization in temperature parallels the equalization of gravity. Highest temperatures found are in the center of the cell. Maximum differences average about 8 degrees Fahrenheit.