Abstract: The anodic behavio of Pb-(0. 075%-0. 73%)Sm-0. 63%Sn and Pb-0. 088%Ca-0. 63%Sn alloys in sulfuric acid solution has been studied by using cyclic voltammetry, linear sweep voltammetry and impedance-time curves. The experimental results show that samarium in the Pb-Sm-Sn alloy can inhibit the growth of the anodic corrosion layer(PbO₂) formed on the alloy. Moreover, the evolution of oxygen at the Pb-Sm-Sn alloy electrode is less than that at the Pb-Ca-Sn alloy electrode. 2V-200 A·h VRLA batteries were manufactured by using the above two alloy positive grids separately. he corrosion layers formed on the positive gird surfaces after the life test of the batteries were observed by SEM. The results of the test show that the capacity loss of the battery with the Pb-Sm-Sn positive grids is significantly less than that of the battery with the Pb-Ca-Sn positive grids, and the longer floating charge life of the battery with the Pb-Sm-Sn positive grids is caused by the better corrosion-resistant performance of the Pb-Sm-Sn alloy with the anodic corrosion layer having a finer grain structure.

Key words: Pb-Sm-Sn alloy, Lead-acid battery, Floating charge potential, Anodic PbO₂corrosion layer