| abstract |
An anode active matter capable of producing a non-aqueous electrolyte secondary battery having a high energy density and being excellent in charge/discharge cycle characteristics, and a non-aqueous electrolyte secondary battery-use anode and non-aqueous electrolyte secondary battery using it. An anode active matter containing a composite oxide represented by a composition formula LiaMn0.5-xNi0.5-yMx+yO2 (0.98≤a< 1.1, -0.1≤x-y≤0.1, M being an element other than Li, Mn, Ni). An anode active matter containing a composite oxide represented by a composition formula LiwMnx'Niy'Coz'O2 (x', y', z' are vales within a range where, on a ternary composition diagram, (x', y', z') exists on a line of or within a quadrangle ABCD having apexes point A (0.51, 0.49, 0), point B (0.45, 0.55, 0), point C (0.25, 0.35, 0.4) point D (0.31, 0.29, 0.4), and 0≤w/(x'+y'+z')≤ 1.30). |