| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium secondary battery with an excellent low-temperature output. <P>SOLUTION: A positive electrode material having a composition expressed in a composition formula: Li<SB>x</SB>Ni<SB>a</SB>(Mn<SB>y</SB>M<SB>1-y</SB>)<SB>b</SB>(Co<SB>z</SB>M'<SB>1-z</SB>)<SB>c</SB>O<SB>2</SB>(where, 0<x<1.2, 0<y<1, 0<z<1, a+b+c=1, 9b≤5a+2.7, 0<a<1, 0<b<1, 0<c<1, M is a quadrivalent element different from Mn, and M' is a trivalent element different from Co.), and having a region where an Mn concentration on the surface of particles constituting positive electrode material powder is higher by 10% or more than the inside of the particles in an atomic percentage. By this, a lithium secondary battery with an excellent low-temperature output can be obtained. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
