CATHODE ACTIVE MATERIAL

摘要

To provide a cathode active material to be used for a positive electrode of a lithium ion secondary battery having a high discharge capacity and favorable cycle durability.;A cathode active material, which comprises a lithium-containing composite oxide containing at least one transition metal element (X) selected from the group consisting of Ni element, Co element and Mn element, and Li element (provided that the molar ratio (Li/X) of the Li element based on the total amount of the transition metal element (X) is from 1.1 to 1.7),;wherein the aspect ratio of primary particles is from 2.5 to 10, and;in an X-ray diffraction pattern, the ratio (I020/I003) of the integrated intensity (I020) of a peak of (020) plane assigned to a crystal structure with space group C2/m to the integrated intensity (I003) of a peak of (003) plane assigned to a crystal structure with space group R-3m is from 0.02 to 0.3.

主权项

1. A cathode active material, which comprises a lithium-containing composite oxide containing at least one transition metal element (X) selected from the group consisting of Ni element, Co element and Mn element, and Li element (provided that the molar ratio (Li/X) of the Li element based on the total amount of the transition metal element (X) is from 1.1 to 1.7),
wherein the aspect ratio of primary particles is from 2.5 to 10, and in an X-ray diffraction pattern, the ratio (I020/I003) of the integrated intensity (Ion) of a peak of (020) plane assigned to a crystal structure with space group C2/m to the integrated intensity (I003) of a peak of (003) plane assigned to a crystal structure with space group R-3m is from 0.02 to 0.3.