| abstract |
A nonaqueous electrolyte secondary battery comprisingn a positive electrode containing a granular positive electrode active material composed of a mixed metal oxide and an M 3 -containing compound (M 3 represents one or more elements selected from the group consisting of Group 3B elements in the periodic table, and the M 3 -containing compound is different from said mixed metal oxide) placed in the form of particles or a layer on the surface of the mixed metal oxide, wherein the positive electrode active material has M 1 (M 1 represents one or more elements selected from the group consisting of alkali metal elements), M 2 (M 2 represents one or more elements selected from the group consisting of Mn, Fe, Co and Ni), M 3 (M 3 has the same meaning as that described above) and O on its surface, and when the molar ratio (M 3 /M 2 ) of the number of M 3 atoms (mol) to the number of M 2 atoms (mol) on the surface of the positive electrode active material is represented by A and the BET specific surface area of the positive electrode active material is represented by S (m 2 /g), A and S satisfy the following formula (1): nn A/S ≧1 (1), a negative electrode, a separator, and a nonaqueous electrolyte. |