Effect of a phenyl vinyl ketone inhibitor on electrochemical behavior of pb-sb alloy as negative grid in lead–acid battery

Effects of phenyl vinyl ketone (PVK) inhibitor on electrochemical behavior of Pb-3%Sb alloy electrode have been studied by linear sweep voltammetry (LSV), cyclic voltammetry (CV) and Tafel polarization measurements. The alloy surface morphology after discharge/charge reactions was studied by using scanning electron microscopy (SEM). Results show that PVK additive may strongly suppress hydrogen evolution even at a low concentration of 20μL.L-1 and reduce the rate of corrosion reaction which occurs on negative electrode grids of the lead- acid battery. The value of inhibition efficiency of PVK additive for corrosion of negative electrode grids is 40.89% to 83.26% with PVK concentrations of 20 to 280μL.L-1. The presence of PVK in electrolyte solution significantly impedes the conversion reactions of negative grid material and makes them more reversible. The effect of PVK additve on conversion coefficients of negative electrode grids is maintained after hundred of CV cycles. The addition of PVK changed surface morphology of alloy electrode. The formed PbSO4 and porous Pb crystals are smaller in size and more compact. The results showed that PVK additieve is promising for use as suitable additives for lead- acid batteries.