Cathodic Behavior of Manganese Dioxide Electrodes in Nonaqueous Organic Electrolyte

Abstract

The cathodic behavior of manganese dioxides electrodeposited on graphite rod was studied in LiClO₄-propylene carbonate, dimetyl sulfoxide, tetrahydrofuran and γ-butyrolactone by means of potential sweep and galvanostatic method.
Upon heating at about 200°C in an air, the manganese dioxide electrode gives the most distinct cathodic peak current on polarization curve and a single plateau potential on discharge curve corresponding to the reduction of oxide toward lower oxidation state. The polarization curve is also cosiderably influenced by the viscosity of organic solvent.
The apparent discharge efficiency decreases with increasing thickness of the manganese dioxide layer deposited on the graphite and with increasing discharge current. The manganese dioxide is very slightly soluble in those organic electrolytes in the discharged state. Results showed that the manganese dioxide seemed to be reduced in the solid state.