Rapid evaluation of the rechargeability of c-MnO₂ in alkaline media by abrasive stripping voltammetry

Abstract

Cyclic abrasive stripping voltammetry is shown to provide the experimental basis for the evaluation of the rechargeability of γ-MnO₂ in 9 M KOH. Relative discharge capacities at different depths of discharge (DOD) with respect to the first one-electron reduction of γ-MnO₂ are compared when metal ions such as Ba²⁺ or Zn²⁺ are additionally present in the electrolyte solution. At about 30% DOD, resulting relative discharge capacities are essentially equal to those of AA cells either in the absence or presence of Ba²⁺ ions from about 10 discharge/charge cycles. However, the corresponding time scales are substantially different. While it takes about 2.7 h to complete 20 discharge/charge cycles in the case of abrasive stripping voltammetric characterization, some 360 h are needed to cycle an AA-sized battery in the conventional manner.