In order to explore how to improve the electrochemical performance of the lead-acid battery positive active material, PbO2 particles with multiple morphologies and phases including urchin-like and ball-like alpha-PbO2 particles with size of 0.5-1 mu m, flower-like beta-PbO2 particles with size of 1-2 j.mu m are chemically synthesized. These samples are composed of different smaller nanoparticles. The electrode made with urchin-like 13-Pb02 and flower-like alpha-PbO2 in the ratio of 1:1 can deliver a discharge capacity of 183 mA h g(-1) at 0.1 C after 100 cycles, and subsequent rate performance test shows that a discharge capacity of 97.2 mA h g(-1) can be obtained even at 1 C. Moreover, this kind of electrode pretreated in 1 M H2SO4 solution displays improved stability of cycle, a capacity of 146.7 mA h g(-1) can be obtained after 100 cycles, and its corresponding active material utilization ratio can reach 65%. (c) 2013 Elsevier B.V. All rights reserved.