Stationary Lead-Acid Batteries With Selenium Alloys

Until ten years ago the grids of lead-acid batteries were usually made of lead-antimony alloys containing 5-11 wt. % antimony. The necessary mechanical strength and castability are easily achieved with this content of antimony. However, the unavoidable corrosion of the positive grid liberates antimony from the grid, which proves to be both unfavorable as well as unfavorable with respect to battery performance. On the one hand, antimony stabilizes the active material of the positive electrode, the cycle life of the battery is improved and passivation effects disturbing mainly the discharge mechanism are not observed when alloys with a high antimony content are used for positive grids. On the other hand, antimony migrates to the negative plate where it is precipitated and reduces the hydrogen over voltage. This leads to lower charge voltage increased self-discharge and therefore increased water loss of the battery.