| 摘要 |
PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery at low cost, high capacity, and long charging/discharging cycle life by using a composite metal oxide having the specified composition containing a large quantity of Li, and Mn and other metals as a positive pole active material precursor. SOLUTION: A LiMn composite metal oxide is obtained by electrochemically implanting lithium ions in the sealed container of a nonaqueous electrolyte lithium ion secondary battery to increase the content of lithium ions. The composition is represented by the formula of Li1+x Mn2-a Ma/c O4+b . (0.3<x<1, 2.0<a<=1.0, 0<=b<0, c=1-4, M is a cation of metal other than Li and Mn). A positive active material precursor mainly comprising this composite metal oxide is obtained and lithium ions are electrochemically released from the precursor to obtain a positive pole active material having the composition represented by Liy Mn2-a Ma/c O4+b (0<y<=1). The released lithium ions are implanted in a negative active material precursor to obtain a negative active material. |
