| 摘要 |
PURPOSE: An active material provides a nonaqueous electrolyte secondary battery with excellent output performance and high voltage performance. CONSTITUTION: An active material for a nonaqueous electrolyte secondary battery contains a lithium transition metal composite oxide which has an α-NaFeO_3 type crystal structure and a composition of Li_(1+α)Me_(1-α)O_2. The lithium transition metal composite oxide is a particle which has a core and a coating part. The cobalt concentration of the coating part is higher than the cobalt concentration of the core. The manganese concentration of the coating part is lower than the manganese concentration of the core. The cobalt ratio in the coating part is 3-10 % to the transition metal ratio in the core. [Reference numerals] (AA) Precursor core particle producing process; (BB,FF) Reaction tub (pH=7.9,50°C); (CC,GG) Mn rich composition (core); (DD,HH) (Co,Ni,Mn) sulphate; (EE) Precursor particle before coating producing method; (II) Sulphate containing (coating)Co |
