| 摘要 |
PROBLEM TO BE SOLVED: To heighten capacity by using mixed active material of composite oxide mainly composed of lithium and manganese having a spinel structure and composite oxide mainly composed of lithium and nickel having a layer-like structure. SOLUTION: A mixture having a weight ratio of A/B>=20/80 is used as a positive electrode active material, where composite oxide mainly composed of lithium and manganese having a spinel structure is LiXMnYOZ (A) and composite oxide mainly composed of lithium and nickel is Lia Nib OZ (B). In a range where A/B is smaller than 20/80, the amount of the LiXMnYOZ in the mixed active material is small so that the safety of a lithium secondary battery in which the Lia Nib OZ is a factor cannot be guaranteed. Also the rapid rise of potential at a discharge end, which is the feature of the LiXMnYOZ, hardly appears in a battery voltage so that circuit design becomes complex to cause high cost. |
