STUDY OF STRUCTURAL FACTORS OF LEAD-ACID-BATTERY ELECTRODES

The electrolyte conductivity in the pores, and the true and apparent densities of the active mass, were measured on electrodes of a starter-type lead-acid battery in various stages of discharge, and the porosity of the plates and the tortuosity factor of the pores were evaluated. The results suggest that the charged, cycled positive plates contain a certain fraction of lead dioxide of a lower density, probably amorphous, which is reduced preferentially. Transport restrictions are more important in positive than in negative plates. Volume changes of a negative plate during cycling were found to be reversible, while with a positive plate they were irreversible. © 1979.