Abstract: A particulate positive electrode active material for a lithium secondary cell which satisfies high charge and discharge cyclic durability, high safety, high temperature storage properties, a high discharge average voltage, large current discharge properties, a high weight capacity density, a high volume capacity density, etc. in a well-balanced manner is provided. A particulate positive electrode active material for a lithium secondary cell, which is represented by the formula LipCoxMyOzFa (wherein M is at least one element selected from Groups 2 to 8, 13 and 14 of the Periodic Table, 0.9?p?1.1, 0.980?x?0.9999, 0.0001?y?0.02, 1.9?z?2.1, 0.9?x+y?1 and 0.0001?a?0.02), wherein fluorine atoms and element M are unevenly distributed on the particle surface, the atomic ratio of fluorine atoms to cobalt atoms (a/x) is from 0.0001 to 0.02, and in powder X-ray diffraction using CuK?-ray, the half value width of the angle of diffraction on (110) plane is from 0.06 to 0.

Abstract: The present invention provides a lithium-transition metal composite oxide having a large volume capacity density, high safety, excellent coating uniformity, excellent charge/discharge cycle durability and excellent low temperature characteristics, and suitable as a positive electrode active material for a lithium secondary cell. A lithium-transition metal composite oxide which is represented by the formula LixM1?yNyO2 (wherein 0.2?x?1.2, 0?y?0.7, M is a transition metal element, and N is a transition metal element other than M or an alkaline earth metal element), wherein in the distribution curve of the cumulative volume particle size of said lithium composite oxide, the inclination of the curve at a cumulative volume fraction of 20% and 80% are at most 9%/?m and at least 3%/?m, respectively, and the average particle size is from 3 to 20 ?m.

Abstract: A particulate positive electrode active material for a lithium secondary cell which satisfies high charge and discharge cyclic durability, high safety, high temperature storage properties, a high discharge average voltage, large current discharge properties, a high weight capacity density, a high volume capacity density, etc. in a well-balanced manner is provided. A particulate positive electrode active material for a lithium secondary cell, which is represented by the formula LipCoxMyOzFa (wherein M is at least one element selected from Groups 2 to 8, 13 and 14 of the Periodic Table, 0.9?p?1.1, 0.980?x?0.9999, 0.0001?y?0.02, 1.9?z?2.1, 0.9?x+y?1 and 0.0001?a?0.02), wherein fluorine atoms and element M are unevenly distributed on the particle surface, the atomic ratio of fluorine atoms to cobalt atoms (a/x) is from 0.0001 to 0.02, and in powder X-ray diffraction using CuK?-ray, the half value width of the angle of diffraction on (110) plane is from 0.06 to 0.

Abstract: The present invention provides a lithium-transition metal composite oxide having a large volume capacity density, high safety, excellent coating uniformity, excellent charge/discharge cycle durability and excellent low temperature characteristics, and suitable as a positive electrode active material for a lithium secondary cell.