CATHODE MATERIAL FOR SECONDARY MANGANESE DIOXIDE AQUEOUS BATTERIES

A cathode material for a secondary aqueous manganese dioxide battery, comprising a compressed mixture of manganese dioxide particles, an electrical conductive additive, and a binder. The manganese dioxide particles are modified such that: 20-100% of an average bulk composition of the manganese dioxide particles has a beta manganese dioxide structure, the rest being other manganese dioxide polymorph structures, Mn3O4 or combinations thereof, and the carbon content of the manganese dioxide particles is 0.001-0.01 wt%. In a method for producing such cathode material, manganese dioxide particles are coated with a coating solution comprising an organic carbon source, the coating solution having an organic carbon concentration of 0.01 to 7.5 % by weight of the manganese dioxide particles. Thereafter the coated particles are dried and heated.