EFFECT OF GELLING ON THE ELECTRODE-KINETICS OF THE PB PBSO4 AND HYDROGEN-ELECTRODE REACTIONS IN MAINTENANCE-FREE LEAD-ACID-BATTERIES/

The electrode kinetics of the Pb/PbSO4 and the hydrogen-evolution reac tions on porous lead electrodes in sulfuric acid has been studied usin g a quantitative analysis of galvanostatic transients in the linear po larization domain. Significant changes are observed in the kinetics wi th the addition of thixotropic agents (e.g., sodium silicate) that are often employed in the manufacture of maintenance-free lead/acid batte ries. The effects of these thixotropic agents on the charge-transfer a nd ohmic components of the Pb/PbSO4 reaction and charge-transfer compo nents of hydrogen-electrode reaction are analysed with the help of a ' pore-plugging' model. This study allows a non-destructive determinatio n of the electrode kinetic parameters and the internal resistance cont ribution from pore-plugging. This is useful when designing maintenance -free lead/acid batteries.