Write the cell reactions which occur in lead storage battery when (i) it is in use (ii) not in use.

Explanation

(i) When battery is in use i.e., in discharging
`Pb(s) +PbO_(2)(s)+4H^(+)(aq)+2SO_(4)^(2-)(aq) to 2PbSO_(4)(s)+2H_(2)O(l)`
(ii) When battery is not in use i.e., in charging
`2PbSO_(4)(s)+2H_(2)O(l) to Pb(s)+PbO_(2)(s)+4H^(+)(aq)+2SO_(4)^(2-)(aq)`