| abstract |
PROBLEM TO BE SOLVED: To provide a method for producing a spinel-type lithium-manganese composite oxide having improved charge / discharge cycle characteristics in a high-temperature (50 ° C. or higher) environment, and a spinel-type lithium-manganese composite oxide produced by the method. The present invention provides a positive electrode active material for a lithium ion secondary battery, comprising: A in the general formula (I) LixMn (2-y ) M yi B y2 O 4 (I) ( wherein at least, M is Al, Cr, Fe, Ni, Co, selected from the group consisting of Ga and Mg One type, x is 0.9 ≦ x ≦ 1.1, y is y = y 1 + y 2 , 0.002 ≦ y ≦ 0.5, 0 ≦ y 1 <0.5, 0.0 02 ≦ y 2 ≦ 0.1) and the following general formula (Ia) Li x Mn (in 2-y) M y O 4 (Ia) ( wherein a y 2 is 0 in the above general formula (I), M, x is As defined above, y is 0.002 ≦ y ≦ 0.5) and a positive electrode active material for a lithium ion secondary battery comprising the spinel-type lithium manganese composite oxide produced by this method. |