| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery which is high in energy density and excellent in safety.SOLUTION: A nonaqueous electrolyte secondary battery has a cathode active material layer which contains a first cathode active material mainly formed of solid solution of LiMnO-LiMO(M represents at least one element selected from Ni,Co,Fe,Al,Mg,Ti,Sn,Zr,Nb,Mo,W,and Bi), and a second cathode active material formed of LiMO(0.1≤a≤1.1,Mrepresents at least one element selected from Ni,Co,Fe,Al,Mg,Ti,Sn,Zr,Nb,Mo,W,and Bi). The rate of the weight of the first cathode active material contained per unit thickness to the total weight of the first and second cathode active materials is set to be higher in the neighborhood of the surface of the cathode active material layer than that in the neighborhood of the interface between the cathode active material layer and a collector. |
