Positive electrode material for non-aqueous secondary battery, method for producing the same, positive electrode for non-aqueous secondary battery using the positive electrode material for non-aqueous secondary battery, and non-aqueous secondary battery using the same

摘要

PROBLEM TO BE SOLVED: To provide a nonaqueous secondary battery which has a high capacity and which has superior charge and discharge cycle characteristics even under a high-voltage condition.SOLUTION: A positive electrode material for a nonaqueous secondary battery comprises lithium-containing composite oxide particles, each including: an outermost surface; a surface layer portion ranging from the outermost surface to a depth of at least 2 nm; and a bulk portion located inward from the surface layer portion. The bulk portion has a composition expressed by the following general formula: LiMO(where M is a single transition metal element or transition metal element group including at least one selected from Co, Ni and Mn). On the outermost surface, a granular Zr oxide having an average particle diameter of 30 nm or less is disposed. A deposit portion is where the Zr oxide is disposed in a region of the outermost surface, and a non-deposit portion is with no Zr oxide deposited; the area of the non-deposit portion is 50-97% of the total area of the outermost surface. The surface layer portion in the non-deposit portion includes M and Zr. The percentage of the total number of Zr atoms included in the surface layer portion in the non-deposit portion to the total number of M atoms included in the surface layer portion in the non-deposit portion is 3-40 atom%.SELECTED DRAWING: Figure 1