| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an active material for a lithium secondary battery which can increase discharge capacity in potential region not more than 4.3V. <P>SOLUTION: The material is an active material for a lithium secondary battery containing solid solution of the lithium transition metal composite oxide having an α-NaFeO<SB>2</SB>type of the crystal structure, wherein the composition ratio of Li, Co, nickel and Mn which the solid solution contains satisfies with the following relation: Li<SB>1+(1/3)x</SB>Co<SB>1-x-y</SB>Ni<SB>(1/2)y</SB>Mn<SB>(2/3) x+(1/2)y</SB>, where, x+y≤1, 0≤y, 1-x-y=z, and in the triangle phase diagram of the system of Li[Li<SB>1/3</SB>Mn<SB>2/3</SB>]O<SB>2</SB>(x)-LiNi<SB>/1/2</SB>Mn<SB>1/2</SB>O2(y)-LiCo<SB>2</SB>(z), a point (x, y, z) is represented with the value of the range which exists on the outline or interior of the quadrangle HIJK which makes vertex points by the point H(0.6, 0.4, 0), the point I(0.67, 0.13, 0.2), the point J (0.7, 0, 0.3) and the point K(0.55, 0.05, 0.4). <P>COPYRIGHT: (C)2011,JPO&INPIT |
