Study on the Improvement of Aging Treatment of Grid Alloy

Abstract

Lead alloys, with several percent of antimony as well as small amounts of tin and arsenic are in use for the grid of lead acid batteries. Though the alloy is age-hardenable at room temperature, at least 3-days aging is required before the alloy becomes hard enough to be safely treated in pasting operation. For the purpose of reducing the aging time to cut down the period necessary for the production, a method of accelerating the aging has been studied. As the result, only 2 hours were found to be necessary for the alloy to attain the first plateau in the aging curve by heating it at 70°C after casting. The result has been successfully applied to the production process of lead-acid batteries in the author’s plant. The influence of additional elements, 0.05 and 1% each of Ag, Te, Se, Na, Cu, Mg, Cd, Zn, has also been investigated. Among the elements considered, Mg, Ag, Se and Cd have been found to accelerate aging but the effect was found to be less than that of keeping the alloy at 70°C.