| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery which has high discharging capacity and is excellent in a cycle characteristic by regulating a particle diameter, a particle diameter distribution width or the like of positive electrode active material particles. SOLUTION: An average particle diameter of particles of a positive electrode active material using LiMn2 Oy is set to 5 to 30μm, and a particle diameter distribution width by converting a width of a minimum and maximum diameter from an average particle diameter into a numeric value by classifying the whole particles by particle diameters, is set not more than 20%, and microscopic particles on which dispersion of particle diameters is extremely reduced and which have a uniform particle diameter are formed. Therefore, filling density of a positive electrode active material is enhanced, and discharging capacity is improved, and it can be flatly and uniformly brought into close contact with a positive electrode core body, and a cycle characteristic is improved. In particles not less than 80% of the whole positive electrode active material particles, a particle diameter distribution width is also made to exist within 10%, and dispersion of particle diameters is reduced, and sufficient filling density of the positive electrode active material is obtained, and initial discharge capacity can be improved, and the deterioration of the cycle characteristic is also restrained. |
