Li-Ni COMPOSITE OXIDE PARTICLES AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

Abstract

The present invention provides positive electrode active substance particles comprising a lithium nickelate composite oxide which have a high energy density and are excellent in repeated charge/discharge cycle characteristics when charging at a high voltage, as well as a non-aqueous electrolyte secondary battery. The present invention relates to positive electrode active substance particles each comprising a core particle X comprising a lithium nickelate composite oxide having a layer structure which is represented by the formula: Li1+aNi1-b-cCobMcO2 wherein M is at least one element selected from the group consisting of Mn, Al, B, Mg, Ti, Sn, Zn and Zr, a is a number of −0.1 to 0.2 (−0.1·a·0.2), b is a number of 0.05 to 0.5 (0.05·b·0.5) and c is a number of 0.01 to 0.4 (0.01·c·0.4); and a coating compound Y comprising at least one element selected from the group consisting of Al, Mg, Zr, Ti and Si and having an average film thickness of 0.2 to 5 nm, in which a crystal phase having a layered rock salt structure and comprising Ni2+ ions is present in the form of a layer between the core particle X and the coating compound Y.

Dependencies are inferred from the claim text.