Theoretical calculations for using positive electrode compression to increase lead-acid battery life

Investigators have confirmed that applying a small amount of mechanical pre ssure, approximately 1 bar (10(5) Pa), to the face of the positive electrod e can dramatically increase the life of deep cycled, lead acid batteries. I n this paper, we calculate the pressures required to stabilize the active m aterial in the positive electrode based on the "Agglomerate of Spheres" mod el. The calculations agree closely with the experimental observations. In a ddition to these calculations, we also provide another possible interpretat ion of the "Agglomerate of Spheres" model and give an improved estimate for the surface tension of lead dioxide, an important physical quantity for th e model. (C) 2000 Elsevier Science S.A. All rights reserved.