| 摘要 |
PROBLEM TO BE SOLVED: To provide excellent performance in load characteristics and charge/ discharge characteristics at a high current density by baking a raw material of a lithium manganese oxide in the no-oxygen atmosphere, and cooling it in the oxygen atmosphere. SOLUTION: A lithium manganese oxide with a spinel structure including oxygen deficiency is synthesized during the baking process of a raw material of a lithium manganese oxide in the no-oxygen atmosphere, and it is active material powder which is suppressed with excess grain growth and has narrow grain size distribution. Oxygen deficiency is complemented during the cooling process in the oxygen atmosphere, thereby the positive electrode active material powder, which has the expected spinel crystal structure, a uniform grain size with excess grain growth suppressed, and narrow grain size distribution, can be obtained. Cr or the like is preferably blended with this lithium manganese oxide. The Mn site of a composition formula LiMn2O4 is substituted by Cr, and the positive electrode active material expressed by a composition formula LiMn2-xCrxO4 (0<=x<=1.0) is obtained. |
