| 摘要 |
PROBLEM TO BE SOLVED: To provide a positive electrode active material for lithium ion secondary batteries in which the quantity of a transition metal existing near the outermost surface is remarkably decreased.SOLUTION: Solid electrolyte-coated positive electrode active material powder comprises particles of a positive electrode active material for lithium ion secondary batteries; the positive electrode active material for lithium ion secondary batteries includes a complex oxide of Li and a transition metal M. The particles each have, on the surface thereof, a coating layer of a solid electrolyte expressed by the formula, LiAlTi(PO), where 0≤X≤0.5. In a depth direction analysis according to XPS, the average percentage of the total number of Al, Ti and P atoms to the total number of Al, Ti, M and P atoms distributing from the outermost layer to a depth of 1 nm is 50% or more. The transition metal M is at least one of e.g. Co, Ni and Mn. |
