Properties and application of lead–calcium–tin–aluminium–bismuth alloys for positive grids

The effects of bismuth addition less than 0.05 wt% on the electrochemical properties of lead–calcium–tin–aluminum alloys were investigated in detail. Passivation and corrosion phenomena were investigated by cyclic voltammetry, electrochemical impedance spectra, linear sweep voltammetry. The effect of bismuth on oxygen evolution and hydrogen evolution were also discussed. The experimental results show that the addition of bismuth leads to the decreases of the hydrogen overpotential and increase of the hydrogen evolution rate. Oxygen evolution rate increases with the increase of content of bismuth. The measurements of cyclic voltammetry suggested that bismuth may promote the formation of lead dioxide. A key result was that the presence of bismuth might have beneficial effect on the formation of Pb(II).