| abstract |
Provided are a surface-modified lithium-containing composite oxide for a positive electrode active material for a lithium ion secondary battery excellent in volume capacity density, safety, charge / discharge cycle durability, and rate characteristics, and a method for producing the same. Li p N x M y O z F a ( where, N is the, Co, at least one element selected from the group consisting of Mn and Ni, M is a transition metal element other than N, Al, Sn and alkaline earth At least one element selected from the group consisting of similar metal elements: 0.9 ≦ p ≦ 1.3, 0.9 ≦ x ≦ 2.0, 0 ≦ y ≦ 0.1, 1.9 ≦ z ≦ 4 .2, 0 ≦ a ≦ 0.05) impregnated with a solution containing a lanthanoid source and a titanium source, and then heat-treated at 550 to 1000 ° C. A surface-modified lithium-containing composite oxide containing a highly crystalline lithium lanthanoid titanium composite oxide having a perovskite structure that does not contain fluorine is produced in the layer. |