2014 Volume 55 Issue 2 Pages 327-333
In this study, nanoscale PbO2 was obtained by the hydrolysis reaction of Pb(CH3COO)4 in an ethanol solution, and the conventional PbO2 was prepared by the electrolytic oxidation of PbO powder in a H2SO4 solution. The former PbO2 was identified as single phase β-PbO2 with the average crystallite size of about 12 nm that had an excellent electrochemical activity, whereas the latter one was a mixture of α-PbO2, β-PbO2 and PbSO4 of about 41 nm average size. A hybrid lead-acid battery cathode consisting of an inner layer of the conventional PbO2 and an outer layer of the nanoscale PbO2 was also manufactured. The average diameter of the pores in the hybrid cathode was smaller than that of the conventional cathode of the lead-acid battery, which was made from only the conventional PbO2. The mass change in the hybrid cathode during the discharge-charge cycle test was relatively high as compared to that of the conventional cathode. Moreover, the cycle tests clearly showed that the reversibility of the discharge-charge reaction was improved in the hybrid cathode since the electrode mass returned to zero even after repeated charge and discharge. As a result, the hybrid cathode was significantly better than the conventional cathode regarding both the current efficiency and the utilization factor of the active materials of the cathode during the discharge-charge reaction. These results may suggest the manufacturing of a novel lead-acid battery with a higher power density and higher capacity.