Lead-acid battery life testing and ultrasonics

The authors describe an ultrasonic grid growth measurement technique that significantly minimizes the number of test cells required for stationary lead-acid battery life testing and provides growth curves that are based on the same plates throughout the test. At four different temperatures, three stationary cells are maintained at each temperature at 80 mV above the PbO₂/PbSO₄ equilibrium potential. Positive plate growth and cell capacities are plotted so that activation energies can be obtained to permit room-temperature life predictions. The actual variation between mechanical and ultrasonic measurements of positive plate growth up to date indicates the difference to be less than 1%. Along with the obvious advantage that a nondestructive plate growth measuring technique provides, the accuracy and other advantages and limitations of the ultrasonic technique are discussed