Modeling oxygen evolution and associated failure mechanisms in lead acid batteries

In this paper, the authors hypothesize that oxygen generated at the positive electrode causes the active material to soften and shed. They believe this mechanism is also responsible for conductivity changes in the positive active material. They suggest that the conductivity changes occur inside the positive plate at those locations where the potentials are highest. They base our analysis on the agglomerate of spheres (AOS) model which, in a previous paper, was used to quantitatively explain the large increase in battery life resulting from a small amount of mechanical pressure applied to the positive electrode. This previous investigation is what made them suspect that the high potentials associated with the neck regions of the spheres causes oxygen to evolve and the necks to deteriorate.