Patent ID: 7718314

Claim:
A cathode material containing a first cathode active material, a second cathode active material, and a third cathode active material, wherein, the first cathode active material is a complex oxide containing lithium (Li), manganese (Mn), nickel (Ni), and cobalt (Co), the second cathode active material is a complex oxide containing lithium and at least one of nickel and cobalt, the third cathode active material is at least a phosphorus oxide containing lithium and iron (Fe), a ratio by the weight ratio of the cathode active materials is a value in the range obtained by joining each dot of A, B, C, and D expressed in Mathematical formula 1, where the first cathode active material is x, the second cathode active material is y, and the third cathode active material is z in a ternary diagram with the apexes set to each cathode active material, and Mathematical Formula 1 is: A ( x,y,z )=(0.76,0.04,0.20) B ( x,y,z )=(0.94,0.05,0.01) C ( x,y,z )=(0.05,0.94,0.01) D ( x,y,z )=(0.04,0.76,0.20) (Mathematical formula 1).