| abstract |
The present invention provides a positive electrode, which has a large volume capacity density, high safety, and is excellent in the coating uniformity, the charge and discharge cyclic durability and the low-temperature properties. n Further, the present invention provides a process for producing a lithium-cobalt composite oxide for a positive electrode for a lithium secondary cell, the lithium-cobalt composite oxide being represented by the formula Li p Co x M y O z F a (wherein M is a transition metal element other than Co, aluminum or an alkaline earth metal element, 0.9≦p≦1.1, 0.980≦x≦1.000, 0≦y≦0.02, 1.9≦z≦2.1, x+y=1 and 0≦a≦0.02), which comprises firing a mixture of a cobalt source, a lithium source, and if required, the following M element source and a fluorine source at a temperature of from 800° C. to 1050° C. in an oxygen-containing atmosphere, characterized in that as the above cobalt source, cobalt hydroxide is used which has a specific surface area of from 5 to 50 m 2 /g, a press density of from 1.0 to 2.5 g/cm 3 and a structure having secondary particles formed by agglomeration of primary particles, and further that the average particle size D50 after the secondary particles are dispersed in a pure water, is at most ¼ of the original average particle size. |