LITHIUM-CONTAINING MANGANESE-DIOXIDE (COMPOSITE DIMENSIONAL MANGANESE OXIDE, CDMO) AS POSITIVE MATERIAL FOR A LITHIUM SECONDARY BATTERY

Lithium-containing manganese dioxide (CDMO) has been developed as the positive material for lithium secondary batteries. CDMO is prepared from lithium salt and manganese dioxide by heat treatment. It is a composite oxide of γ/β-MnO2 and Li2MnO3. The influence on rechargeability of lithium salts, heat-treatment temperature, and manganese dioxide type has been investigated by conducting cycle tests with flat cells. Lithium hydroxide is more reactive with MnO2 in the production of Li2MnO3 than either Li2O or Li2CO3. The optimum condition for preparing CDMO is to heat treat LiOH and MnO2 at about 375 °C. CDMO prepared from EMD (electrolytic manganese dioxide) yields a larger and more stable capacity than CDMO prepared from CMD (chemical manganese dioxide). Sodium-free EMD exhibits the largest discharge capacity. © 1990.