| 摘要 |
PROBLEM TO BE SOLVED: To provide a positive electrode active material of "lithium-excessive type" for a nonaqueous electrolyte secondary battery, which is superior in the capacity-keeping rate in charge and discharge cycles by setting a specific surface area appropriately.SOLUTION: A positive electrode active material for a nonaqueous electrolyte battery, comprises a lithium transition metal composite oxide having a crystal structure of α-NaFeOtype. The mole ratio Li/Me of Li and a transition metal(Me) which the lithium transition metal composite oxide includes is 1.2 to less than 1.5. The transition metal(Me) includes Mn and Ni; the lithium transition metal composite oxide has an X-ray diffraction pattern which can be identified as belonging to a space group P312 or R3-m; with Miller indices hkl according to X-ray diffraction measurement by Cu Kα rays, the half-value width of a diffraction peak of (003) plane is 0.180-0.210°; and the BET specific surface area of the lithium transition metal composite oxide is 2.0-3.8 m/g.SELECTED DRAWING: Figure 1 |
