| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium secondary battery which has a large output and of which degradation of life property, in particular, the input and output property caused by charge and discharge cycle at high temperatures can be suppressed. <P>SOLUTION: Lithium manganate of which the average particle size of the secondary particles, which are made of a particle A having an average particle size 0.5-1 μm and a particle B having an average particle size 2-3 μm, is made 10-30 μm, having spherical shape, is used for the positive electrode active material. The ratio N<SB>A</SB>/ N<SB>B</SB>, the ratio of quantity N<SB>A</SB>of the particle A to the quantity N<SB>B</SB>of the particle B is made to range between 5 and 20. Since lithium manganate having spherical shape of its secondary particles is used, conductive material enters into the active materials and the contact area between the active material and the conductive material is increased. Further, the specific surface area is made large by the particle A and the reaction area of the electrode is increased, and by the particle B, the cohesion between the particles becomes large, thereby, elution of manganese can be suppressed. <P>COPYRIGHT: (C)2004,JPO |
