CATHODE MATERIAL FOR SECONDARY BATTERY HAVING ALKALI METAL ANODE

摘要

PURPOSE:To improve reversibility of charge-discharge cycles by adding vanadium oxide or a vanadium salt to MnO2 as a cathode active mass and quenching the mixture after heat treatment. CONSTITUTION:MnO2 and vanadium oxide are heated to react each other in the interface between their particles under the condition of mixed uniformly and the crystal structures of MnO2 and V2O5 are changed and strains are produced by quenching the mixture after the heat treatment. As a result, insertion and desertion of an alkali metal become easy and thus charge-discharge cycle property is improved. Since the most of vanadium oxide remains as V2O5, a discharge curve of an electrode using this active mass shows, as a whole, two step discharge pattern which is particular in V2O5 and the discharge capacity of an electrode using a simple mixture of MnO2 and V2O5 is remarkably improved as compared with those of electrodes using solely MnO2 and V2O5.