Pb3O4 has been investigated as a cathode material for voltage compatible, nonaqueous lithium cells and its good performance has been demonstrated. The mechanism of the process has been elucidated by undertaking X-ray and XPS analyses of the discharge products at significant points of the discharge curve. Pb(II) was unambiguously recognized by the latter technique, thus evidencing a two-step reduction mechanism en route to Pb(O) during lithiation.