The tin content of the lead-calcium-tin alloys, used in the positive grids of the Ieadfacid batteries, must be controlled at a sufficient level to avoid passivation, mainly under deep discharge conditions. The passivation phenomenon is attributed to the formation of a semiconductive PbO layer, growing under a porous superficial layer of PbSO4. Electrochemical measurements, as well as TEM and SIMS experiments have established that the PbO growth is controlled by the diffusion of ...
Keywords : lead/acid batteries, corrosion, passivation, lead-calcium-tin alloys, electrochemistry, TEM, SIMS