A positive electrode active material for a non-aqueous electrolyte secondary battery includes a lithium metal composite oxide, wherein the lithium metal composite oxide is represented by a general formula: Li.sub.aNi.sub.1xyzCo.sub.xD.sub.yE.sub.zO.sub.2 (wherein, in the formula, 0.05x0.35, 0y0.35, 0.002z0.05, 1.00a1.30, an element D is at least one type of element selected from Mn, V, Mo, Nb, Ti, and W, and an element E is an element forming an alloy with lithium at a potential more noble than a potential in which ions of the element E are reduced), wherein the lithium metal composite oxide includes primary and secondary particles formed by aggregating the primary particles, wherein an oxide containing the element E exists at a surface of at least either of the primary and secondary particles.

Disclosed is a lithium complex oxide and method of manufacturing the same, more particularly, a lithium complex oxide effective in improving the characteristics of capacity, resistance, and lifetime with reduced residual lithium and with different interplanar distances of crystalline structure between a primary particle locating in a internal part of secondary particle and a primary particle locating on the surface part of the secondary particle, and a method of preparing the same.

A positive electrode active material has a small difference in a crystal structure between the charged state and the discharged state. For example, the crystal structure and volume of the positive electrode active material, which has a layered rock-salt crystal structure in the discharged state and a pseudo-spinel crystal structure in the charged state at a high voltage of approximately 4.6 V, are less likely to be changed by charging and discharging as compared with those of a known positive electrode active material. In order to form the positive electrode active material having the pseudo-spinel crystal structure in the charged state, it is preferable that a halogen source such as a fluorine and a magnesium source be mixed with particles of a composite oxide containing lithium, a transition metal, and oxygen, which is synthesized in advance, and then the mixture be heated at an appropriate temperature for an appropriate time.

Provided is a nickel-containing composite hydroxide that is a precursor of a positive-electrode active material with which a nonaqueous-electrolyte secondary battery having a low irreversible capacity and a high energy density can be configured. An aqueous alkaline aqueous solution and a complexing agent are added to an mixed aqueous solution including at least nickel and cobalt to regulate the pH (measured at a reference liquid temperature of 25 C.) of this mixed aqueous solution to 11.0 to 13.0, the ammonium concentration to 4 to 15 g/L, and the reaction temperature to 20 C. to 45 C. Using stirring blades having an inclination angle of 20 to 60 with respect to a horizontal plane, the mixture is stirred to conduct a crystallization reaction under such conditions that when the nickel-containing composite hydroxide to be obtained is roasted in air at 800 C. for 2 hours, the roasted composite hydroxide has a BET value of 12 to 50 m.sup.2/g. Thus a nickel-containing composite hydroxide expressed by Ni.sub.1-x-yCo.sub.xAl.sub.yM.sub.t(OH).sub.2+ (where, 0<x0.20, 0<y0.15, 0t0.10, 0 0.50, and M is one or more kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y), or the general formula: Ni.sub.1-x-zCo.sub.xMn.sub.zM.sub.t(OH).sub.2+ (where 0<x0.50, 0<z0.50, x+z0.70, 0t0.10, 00.50, and M is one or more kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y) is obtained.

Provided is a positive electrode active material that is capable of simultaneously improving the battery capacity, output characteristics and cycling characteristics of a secondary battery. When obtaining a transition metal-containing composite hydroxide that is a precursor to the positive electrode active material, by adjusting the pH value of a reaction aqueous solution to be within the range 12.0 to 14.0 and performing generation of nuclei (nucleation), and then adjusting the pH value of the reaction aqueous solution to be within the range 10.5 to 12.0 and causing the nuclei to grow (particle growth), atmosphere control is performed at least one time in which the reaction atmosphere during nucleation and in the initial stage of particle growth is adjusted to be a non-oxidizing atmosphere, and during particle growth is switched to be an oxidizing atmosphere having an oxygen concentration that is 5% by volume or more by directly introducing an oxidizing gas into the reaction aqueous solution while continuing the supply of a raw material aqueous solution, and then is further switched to a non-oxidizing atmosphere by directly introducing an inert gas into the reaction aqueous solution while continuing the supply of the raw material aqueous solution.

Provided is a composite metal oxide which is represented by Formula (1) and has an -NaFeO.sub.2 type crystal structure, in which a peak half value width of a (104) plane to be measured by powder X-ray diffraction is 0.250 or less at 2.

Na.sub.xM.sup.1.sub.r(Fe.sub.yNi.sub.zMn.sub.wM.sub.1yzw)O.sub.2(1) (in Formula (1), M represents any one or more elements selected from the group consisting of B, Si, V, Ti, Co, Mo, Pd, Re, Pb, and Bi, M.sup.1 represents any one or more elements selected from the group consisting of Mg and Ca, and relations 0r0.1, 0.5x1.0, 0.1y0.5, 0<z<0.4, 0<w<0.4, 00.05, and y+z+w1 are satisfied)

Provided is a nickel-containing composite hydroxide that is a precursor of a positive-electrode active material with which a nonaqueous-electrolyte secondary battery having a low irreversible capacity and a high energy density can be configured. An aqueous alkaline aqueous solution and a complexing agent are added to an mixed aqueous solution including at least nickel and cobalt to regulate the pH (measured at a reference liquid temperature of 25 C.) of this mixed aqueous solution to 11.0 to 13.0, the ammonium concentration to 4 to 15 g/L, and the reaction temperature to 20 C. to 45 C. Using stirring blades having an inclination angle of 20 to 60 with respect to a horizontal plane, the mixture is stirred to conduct a crystallization reaction under such conditions that when the nickel-containing composite hydroxide to be obtained is roasted in air at 800 C. for 2 hours, the roasted composite hydroxide has a BET value of 12 to 50 m.sup.2/g. Thus a nickel-containing composite hydroxide expressed by Ni.sub.1xyCo.sub.xAl.sub.yM.sub.t(OH).sub.2+ (where, 0<x0.20, 0<y0.15, 0t0.10, 0 0.50, and M is one or more kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y), or the general formula: Ni.sub.1xzCo.sub.xMn.sub.zM.sub.t(OH).sub.2+ (where 0<x0.50, 0<z0.50, x+z0.70, 0t0.10, 00.50, and M is one or more kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y) is obtained.

A method of manufacturing a positive electrode material for a battery, wherein the material is a complex oxide whose overall composition is Li.sub.aNi.sub.bM.sub.cN.sub.dL.sub.eO.sub.x, M: is selected from the group consisting of Mn and Co, N: is one, two, or more chemical elements selected from the group consisting of Mg, Al, Ti, Cr, and Fe, L: is one, two, or more chemical elements selected from the group consisting of B, C, Na, Si, P, S, K, Ca, and Ba, and where a/(b+c+d): 0.80 to 1.30, b/(b+c+d): 0.30 to 0.95, c/(b+c+d): 0.05 to 0.60, d/(b+c+d): 0.005 to 0.10, e/(b+c+d): 0.0005 to 0.010, b+c+d=1, and x: 1.5 to 2.5, the method including mixing raw material chemical elements or compounds containing raw material chemical elements, baking the resultant raw materials at a temperature of 700 C. or higher and 950 C. or lower in a baking process, and thereafter performing a treatment using a water-washing process.

An organic matter decomposition catalyst that contains a perovskite type complex oxide represented by A.sub.xB.sub.yM.sub.zO.sub.w, wherein A contains 90 at % or more of at least one element selected from the group consisting of Ba and Sr, B contains 80 at % or more of Zr, M is at least one element selected from the group consisting of Mn, Co, Ni, and Fe, y+z=1, x>1, z<0.4, and w is a positive value that satisfies electrical neutrality.

The invention relates to electrodes comprising doped nickelate-containing compositions comprising a first component-type comprising one or more components with an O3 structure of the general formula: A.sub.aM.sup.1vM.sup.2wM.sup.3xM.sup.4yM.sup.5zO.sub.2 wherein A comprises one or more alkali metal selected from sodium, lithium and potassium M.sup.1 is nickel in oxidation state 2+, M.sup.2 comprises one or more metals in oxidation state 4+, M.sup.3 comprises one or more metals in oxidation state 2+, M.sup.4 comprises one or more metals in oxidation state 4+, and M.sup.5 comprises one or more metals in oxidation state 3+ wherein 0.85a1; 0<v<0.5; at least one of w and y is >0; x0; z0; and wherein a, v, w, x, y and z are chosen to maintain electroneutrality; together with one or more component-types selected from a second component-type comprising one or more components with a P2 structure of the general formula: A.sub.a<M.sup.1vM.sup.2wM.sup.3x<M.sup.4y<M.sup.5zO.sub.2 wherein A comprises one or more alkali metal selected from sodium, lithium and potassium; M.sup.1 is nickel in oxidation state 2+, M.sup.2 comprises one or more metals in oxidation state 4+, M.sup.3 comprises one or more metals in oxidation state 2+, M.sup.4 comprises one or more metals in oxidation state 4, and M.sup.5 comprises one or more metals in oxidation state 3+ wherein 0.4a<1; 0<v<0.5; at least one of w and y is >0; x0, preferably x>0; z>0; and wherein a, v, w, x, y and z are chosen to maintain electroneutrality; and a third component-type comprising one or more components with a P3 structure of the general formula: A.sub.aM1.sub.vM2.sub.wM.sup.3.sub.xM.sup.4.sub.yM.sup.5.sub.zO.sub.2 wherein A comprises one or more alkali metals selected from sodium, lithium and potassium; M.sup.1 is nickel in oxidation state 2+, M.sup.2 comprises one or more metals in oxidation state 4+, M.sup.3 comprises one or more metals in oxidation state 2, M.sup.4 comprises one or more metals in oxidation state 4+, and M.sup.5 comprises one or more metals in oxidation state 3+ wherein 0.4a<1, 0<v<0.5, At least one of w and y is >0; x0; z0; and wherein a, v, w, x, y and z are chosen to maintain electroneutrality.