Effect of Surfactants on the Electrochemical Behavior of the Positive Plate

The main goal of this research is to improve the performance of positive plate of lead-acid battery using surfactants in 0.5 M H2SO4. The use of surfactants aims to increase the ability and the cycle life of the positive active material. The electrochemical behavior of pure lead and PbO2 electrodes interface was investigated at room temperature by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and potential-dynamic polarization curves. Scanning electron microscopy (SEM) was used to explore the film layer morphology deposited on the surface of working electrodes. Cyclic voltammograms of pure lead (Pb) electrode show that in the presence of PS the current peaks of the transition of PbO2 to PbSO4 and PbO2 to PbSO4 dropped at small concentrations of surfactants. We observed a remarkable improvement of the discharge capacity of the PAM for an amount of PS ranging between 10 and 50 ppm. EIS results indicate the improvement of mass transport by the decrease of resistance.In the other hand, the PbSO4 surface layers and the crystal size of PbSO4 changes with impact effect of surfactants. As a result of the morphological changes which occurred, the PbO2 films formed are hardly more reducible with PbSO4 and delays the appearance of resistive PbSO4 layers at the material interface. As a conclusion, we can say that the electrical performance of the battery increase by extending the life cycle.