Sulphation: During normal discharge of battery Pb so4 is formed. This Pb so4 is chemically reversible by passing current. These split up to their original constituents. But under certain condition crystalline lead sulphate is formed (Example: under charging after some time without trickle charging). This Pb so4 is chemically irreversible. So if the sulphation occurs the battery life decreases. Efficiency decreases and the active material starts falling of the grid.
