| abstract |
The production method inexpensively provides a composite compound which comprises nickel and cobalt with few impurities, and serves as a precursor for the positive electrode active material of a lithium ion secondary battery. The composite compound is safe, has a high service capacity, has a superior charge/discharge cycle durability and can be used with a wide range of voltages. The production method for a composite compound comprising nickel, cobalt and an M element is characterized in that an aqueous solution or dispersion comprising nickel, cobalt and an M element is obtained by mixing a nickel ammine complex, a cobalt ammine complex and an M element source, and the aqueous solution or dispersion is heated to thermally decompose the nickel ammine complex and cobalt ammine complex and thereby produce a composite compound containing nickel, cobalt and an M element. |