Cathode materials for lithium ion batteries with high specific discharge capacity and processes for synthesizing these materials

摘要

Positive electrode active materials are described that have a very high specific discharge capacity upon cycling at room temperature and at a moderate discharge rate. Some materials of interest have the formula Li1+xNiMnCOO2, where x ranges from about 0.05 to about 0.25, ranges from about 0.1 to about 0.4, ranges from about 0.4 to about 0.65, and ranges from about 0.05 to about 0.3. The materials can be coated with a metal fluoride to improve the performance of the materials especially upon cycling. Also, the coated materials can exhibit a very significant decrease in the irreversible capacity lose upon the first charge and discharge of the cell. Methods for producing these materials include, for example, a co-precipitation approach involving metal hydroxides and sol-gel approaches.