| 摘要 |
PROBLEM TO BE SOLVED: To provide: a positive electrode active material which exhibits a high rate characteristic when raising a charging voltage to increase a charge depth for the purpose of materializing a lithium ion secondary battery with a higher performance; and a lithium ion secondary battery arranged by use of such a positive electrode active material.SOLUTION: A positive electrode active material of the present invention comprises: a positive electrode active material base material including a lithium complex oxide expressed by the general formula, LiNiCoMO(where M represents at least one element of Mg, Ca, Sr, Ba, Ti, Al, Cr, Mn, Fe, Ge, W, Cu and Zn, 0.95≤a≤1.3, 0<x<1.0,0≤y<0.5, 0≤z<0.65) or LiMPO(where M represents at least one element of Fe, Mn, Co, Ni, V and VO); and a coating layer covering at least a part of the positive electrode active material base material. The coating layer includes FeOor FeO.SELECTED DRAWING: Figure 1 |
