PbO2 (s) + 3H+ + HSO4- + 2e- => PbSO4 (s) + 2H2O @ 1.685vSince Pb compounds are mostly insoluble, there is never any significant amount of lead in the solution, so the electrolyte is mostly made up of H2O + H2SO4.Now, if we look at adding MgSO4 to the battery, instead ...