Defining a recombination efficiency for sealed, lead-acid batteries: a material balance approach

The term recombination efficiency has been applied throughout the literature to sealed, lead-acid batteries that operate on the principle of the ''oxygen cycle.'' In these systems oxygen gas from the positive electrode is recombined at the negative electrode and the evolution of hydrogen is suppressed. Present definitions describe only in part the true state of the overcharge processes in these systems. A complete material balance is described which accounts for overcharge and rigorously defines recombination efficiency in terms of both oxygen recombination and hydrogen suppression. This material balance is applied to data from non-antimonial, sealed, gelled-electrolyte, lead-acid batteries.