The common manganese dioxides IC2 and Tekkosha are rechargeable only for 18 and 10 cycles, respectively, when the depth of discharge is similar to 0.5 e/Mn. This low cycle life is due to the production of Mn3O4 during cycling. When the oxygen evolution is combined with electrochemical oxidation, these samples become rechargeable for 60-70 cycles. The increase in the cycle life is due to the oxidation of Mn3O4 to the initial MnO2 by oxidizing species generated near the Mn3O4 sites during oxygen evolution by overcharging. The overrecharging has a positive effect when the duration of the recharge stage does not exceed similar to 50% of that of the discharge stage. Beyond this value the cycle life decreases.