Development of advanced lead acid batteries for electric vehicles. The use of additives to increase performance and extend life. II. Gel cells

In this work, additives have been incorporated in the paste materials to improve the capacity and the life of the lead-acid battery. The battery's capacity is improved by additives that permanently increase the porosity of the positive active material and therefore the acid supply in the positive plate. Another material that has intrinsic conductivity was also added to permanently enhance the conductivity of the positive paste body. Antimony grids have historically given long service life at the cost of high water loss catalyzed by deposition of antimony on the negative active material. To combat the negative effects of antimony alloys, antimony-absorbing agents were dispersed into the negative active material to preferentially absorb and irreversibly bind the antimony ions, thereby protecting the active material. In this work, the authors have evaluated the use of these performance-improving additives in gelled electrolyte valve-regulated lead acid (VRLA) batteries.