On the base of an analysis of some literature is shown that a solid state reaction mechanism can have several advantages over a dissolution–precipitation mechanism as the most convenient way to describe the Pb/H2SO4 interface in the PbSO4 region, at least for some of the possible experimental conditions. In support of this view, quantitative analyses of the voltammetric results for the formation and reduction of PbSO4 are presented, showing that it is possible to obtain the kinetic parameters of the reactions occurring at the Pb/PbSO4 interface. From these analyses, it is possible to gain a deeper understanding of how the negative plates of lead acid batteries operate efficiently.