| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery having a high energy density and excellent in safety and provide a positive electrode active material for use in the lithium ion secondary battery. <P>SOLUTION: A Li-containing composite oxide is formed from a plurality of transition metal elements selected among Cr, Mn, Fe, Co, Ni, and Cu, wherein the composition of the transition metal elements should be such that no particular element shares to much. The crystal structure of the composite oxide is such that the extent of the angle β formed between the crystalline a-axis and c-axis is controlled to 90°<β≤110°. The obtained composite oxide is used as the positive electrode active material of the intended lithium ion secondary battery. <P>COPYRIGHT: (C)2004,JPO |
