Patent ID: 8137840

Claim:
A nonaqueous secondary battery comprising: a positive electrode having a positive electrode mixture layer, a negative electrode, and a nonaqueous electrolyte, wherein the positive electrode comprises an active material consisting of at least three lithium-containing transition metal oxides having different average particle sizes and at least five inflection points in a particle size distribution curve of the mixture of said at least three lithium-containing transition metal oxides, wherein the lithium-containing transition metal oxides comprise at least one transition metal element M 1 selected from the group consisting of Co, Ni and Mn, and the transition metal element M 1 of the lithium-containing transition metal oxide having the smallest average particle size is partially substituted with a metal element M 2 other than the transition metal element M 1 , wherein the transition metal element M 2 comprises Mg and at least one metal element selected from the group consisting of Ti, Zr, Ge, Nb, Al and Sn, wherein a content of the transition metal element M 2 in the lithium-containing transition metal oxide having the smallest average particle size is largest among said at least three lithium-containing transition metal oxides.