Non-aqueous electrolyte secondary cell
The present invention aims to improve cycling characteristics with maintaining high capacity, which is a feature of lithium-nickel composite oxide, and provides a non-aqueous electrolyte secondary battery comprising a positive electrode which is configured by applying on a current collector a mixture which comprises: a lithium-containing composite oxide having a hexagonal system structure, wherein Co is substituted for part of nickel in a lithium-nickel composite oxide (the substitution percentage ranges from 5 to 30%) and, in addition, at least one kind of such elements as Al, Mn, Ti, and Mg is substituted (the substitution percentage is less than 20%); a binder; and a conductive material; and said lithium-containing composite oxide is characterized in that a half width of the (110)-plane-based diffraction peak obtained from powder X-ray diffraction method, in which CuKα line is used as characteristic X-ray, is larger than 0.13° and smaller than 0.20°, and that the ratio of the (003)-plane-based diffraction peak intensity to the (104)-plane-based diffraction peak intensity is larger than 1.2 and smaller than 1.8.
1 . A non-aqueous electrolyte secondary battery comprising a positive electrode which is configured by applying on a current collector a mixture which comprises:
a lithium-containing composite oxide having a hexagonal system structure, wherein Co is substituted for part of nickel atoms in the crystal lattice in a lithium-nickel composite oxide which is represented by a general equation, LiNiO 2 , (provided that the substitution percentage ranges from 5% to 30% of the number of nickel atoms in said lithium-nickel composite oxide) and, in addition, at least one element which is selected from a group consisting of Al, Mn, Ti, and Mg is substituted (provided that the substitution percentage is less than 20% of the number of nickel atoms in said lithium-nickel composite oxide),
a binder, and
a conductive material;
wherein said lithium-containing composite oxide is characterized in that a half width of the (110)-plane-based diffraction peak obtained from powder X-ray diffraction method, in which CuKα line is used as characteristic X-ray, is larger than 0.13° and smaller than 0.20° and that the ratio of the (003)-plane-based diffraction peak intensity to the (104)-plane-based diffraction peak intensity is larger than 1.2 and smaller than 1.8.
2 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein said lithium-containing composite oxide is represented by the general equation, Li w Ni x Co y M z O 2 , (provided that M is at least one element which is selected from Al, Mn, Ti, or Mg, 0<w≦1.2, 0.95≦x+y+z≦1.05, 0.5≦x≦0.9, 0.05≦y≦0.3, and 0<x≦0.2.)
3 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein said lithium-containing composite oxide is represented by the general equation, Li w Ni x Co y Al z O 2 , (provided that 0<w1.2, 0.95≦x+y+z≦1.05, 0.7≦x≦0.85, 0.1≦y≦0.2, and 0.01<z≦0.1.)