Evaluation of a commercial lignin sample as expander for lead-acid battery negative plate by cyclic voltammetry studies

The effect of BnSO4 and commercial lignin as additive, individually and in combination, on the performance of the negative plate of a lead acid battery was studied in sulfuric acid medium by cyclic voltammetry. The cyclic voltammograms were analysed to study the oxidation-reduction reaction of the negative plate. The results showed that the beneficial effect of BaSO4 and the lignin sample on the discharge reaction of the lead electrode was as expected. The results indicate a dissolution-precipitation mechanism operating In the passivation of lead in sulfuric acid electrolyte. A concentration of 30 ppm of the lignin sample in sulfuric acid was found to be the optimum amount in terms of the negative plate performance.