RECHARGEABILITY OF A CHEMICALLY MODIFIED MNO2 ZN BATTERY SYSTEM AT PRACTICALLY FAVORABLE POWER LEVELS/

Chemically modified (CM) rechargeable MnO2 cathodes, based on a publis hed and patented procedure developed at Ford Motor Company, have been prepared and their electrochemical performances investigated. The CM M nO2 cathodes were characterized by (i) good rechargeability, (ii) high energy and power densities, (iii) achievement of high charging/discha rging rates at a surprisingly constant working voltage, and (iv) low c ost. Use of an ion-selective separator enables the CM MnO2 to be used in a secondary alkaline MnO2 battery system with a Zn anode and apprec iable cycle-life to be realized. These characteristics make the second ary CM MnO2/Zn battery system a promising candidate for electric vehic le applications and also for many other market niches currently occupi ed by Ni-Cd secondary and MnO2/Zn primary cells.