| abstract |
The present invention relates to positive electrode active material particles, each comprising: a core particle X, the core particle X comprising a lithium nickelate composite oxide having a layer structure, the composite oxide having the formula Li 1+a Ni 1-b- c Co b M c O 2 represents, wherein M is at least one element selected from Mn, Al, B, Mg, Ti, Sn, Zn and Zr; coating compound Y, which includes selected from Al, Mg, Zr, Ti and Si At least one element; and coating compound Z, which includes Li element, wherein the content of lithium hydroxide LiOH in the positive electrode active material particles is not more than 0.40wt%, and the content of lithium carbonate Li in the positive electrode active material particles 2 CO 3 Not more than 0.65wt%, and the weight ratio of lithium carbonate content to lithium hydroxide content is not less than 1. |