Abstract: A positive electrode material for a nickel metal hydride secondary battery and a method for producing the positive electrode material for a nickel hydrogen secondary battery, capable of improving characteristics of a nickel metal hydride secondary battery by lowering volume resistivity, are provided. The positive electrode material for a nickel metal hydride secondary battery has, in a differential pore distribution in which a pore diameter range is 1.7 nm or more and 300 nm or less, a local maximum value of a highest peak of a differential pore volume positioned in a range of a pore diameter of 1.7 nm or more and 10.0 nm or less.

Abstract: A nickel-containing hydroxide particle covered with cobalt capable of preventing cracks and fissures in the particle and fine powder from being generated due to having an excellent particle strength is provided. The nickel-containing hydroxide particle covered with cobalt, including a covering layer containing cobalt oxyhydroxide formed on a nickel-containing hydroxide particle, wherein an average particle strength is 65.0 MPa or more and 100.0 MPa or less for a particle diameter with a cumulative volume percentage of 50% by volume (D50) of 10.0 ?m or larger and 11.5 ?m or smaller.

Abstract: The nickel-containing hydroxide particle covered with cobalt, wherein in a volume-based particle size distribution, the nickel-containing hydroxide particle covered with cobalt has the maximum peak with a height a, one peak at a height of (½)a or higher, and has a value A of formula (1) calculated from a width b of the maximum peak at a height of (½)a, and in a volume-based particle size distribution after compression treatment, the nickel-containing hydroxide particle covered with cobalt has the maximum peak with a height c, and has a value B of formula (2) calculated from a width d of the maximum peak at a height of (½)c, and wherein the value B and the value A have a relation represented by formula (3): A=[(b×(½)a]/2??(1) B=[(d×(½)c]/2??(2) ?1.50?[(B?A)/A]×1005.

Abstract: A positive electrode active material for an alkaline storage battery having excellent over-discharge tolerance and high-temperature tolerance, and a method for producing the positive electrode active material. A positive electrode active material for an alkaline storage battery, containing a hydroxide particle containing at least nickel and solid-solubilized cobalt, and a covering layer containing cobalt, the covering layer covering the hydroxide particle, in which cobalt contained in the covering layer and cobalt contained in the hydroxide particle each have a diffraction peak between diffraction angles of 65° and 66°, the diffraction angles each represented by 2? in a diffraction pattern obtained by X-ray diffraction measurement.

Abstract: Provided is a nickel composite hydroxide capable of reducing a calcination temperature when producing a positive electrode active material, and a positive electrode active material using the nickel composite hydroxide as a precursor. The nickel composite hydroxide for a precursor of a positive electrode active material of a non-aqueous electrolyte secondary battery, wherein when in the nickel composite hydroxide, a peak intensity of a diffraction peak on a (200) plane in powder X-ray diffraction measurement using CuK? rays is defined as ?, and a peak intensity of a diffraction peak on a (013) plane in powder X-ray diffraction measurement using CuK? rays is defined as ?, a value of ?/? is 0.75 or more and 0.95 or less, and the nickel composite hydroxide comprises Ni, Co, Mn, and one or more additive elements M selected from the group consisting of Al, Fe, Ti and Zr.

Abstract: The positive electrode active material particle for a secondary battery, containing a metal and/or a metal compound; and a nickel-containing composite compound, wherein a value of X is 0.00 or more and 0.08 or less. X=(C?A)/B ??(I) wherein A means a molar ratio of an amount of the metal in the metal and/or the metal compound to an amount of metals in the nickel-containing composite compound at a secondary particle diameter D90, B means a molar ratio of an amount of the metal in the metal and/or the metal compound to an amount of the metals in the nickel-containing composite compound at a secondary particle diameter D50, and C means a molar ratio of an amount of the metal in the metal and/or the metal compound to an amount of the metals in the nickel-containing composite compound at a secondary particle diameter D10.

Abstract: A positive electrode active material includes a composite particle. The composite particle includes a core particle and a covering layer. The core particle includes a nickel composite hydroxide. The nickel composite hydroxide is represented by the following formula: Nix1Zn1-x1-y1Coy1(OH)2 (where x1 and y1 satisfy 0.90?x1<1.00, 0?y1?0.01, and 0<(1?x1?y1)). The covering layer covers at least a part of a surface of the core particle. The covering layer includes a cobalt compound. In an X-ray absorption fine structure obtainable through measurement by a total electron yield method with soft X-ray, cobalt L3 absorption edge has a peak top in a range not less than 780.5 eV.

Abstract: A positive electrode active material for an alkaline storage battery having excellent over-discharge tolerance and high-temperature tolerance, and a method for producing the positive electrode active material. A positive electrode active material for an alkaline storage battery, containing a hydroxide particle containing at least nickel and solid-solubilized cobalt, and a covering layer containing cobalt, the covering layer covering the hydroxide particle, in which cobalt contained in the covering layer and cobalt contained in the hydroxide particle each have a diffraction peak between diffraction angles of 65° and 66°, the diffraction angles each represented by 2? in a diffraction pattern obtained by X-ray diffraction measurement.

Abstract: To provide a positive electrode active material for an alkaline storage battery having an excellent utilization factor even under a high-temperature condition. A positive electrode active material for an alkaline storage battery, having a hydroxide particle containing nickel, the hydroxide particle containing solid-solubilized cobalt, and a covering layer containing cobalt, the covering layer covering the hydroxide particle, in which the positive electrode active material has a diffraction peak between diffraction angles of 65° and 66°, the diffraction angles represented by 2? in a diffraction pattern obtained by X-ray diffraction measurement, a content by percentage of trivalent cobalt in the solid-solubilized cobalt is 30% by mass or more, a ratio of a content by percentage of the solid-solubilized trivalent cobalt in positive electrode active material particles for an alkaline storage battery, the particles having a secondary particle diameter (?D10) where a cumulative volume percentage is 10.

Abstract: An objective of the present invention is to provide a positive electrode active material that can inhibit the capacity changes associated with temperature variations, and an alkaline battery that contains this positive electrode active material. Aluminum and ytterbium are at least partially solid-dissolved in nickel hydroxide in the nickel composite hydroxide present in the positive electrode active material of the present invention.

Abstract: The present disclosure provides a positive electrode active material for sodium ion secondary batteries which has an excellent charge/discharge capacity and can reduce production costs The positive electrode active material for sodium ion secondary batteries comprises an oxyhydroxide containing: Ni or Ni and at least one transition metal element selected from the group consisting of Mg, Mn, Zn, Co and Al; Na; and S.

Abstract: An objective of the present invention is to provide a positive electrode active material that can inhibit the capacity changes associated with temperature variations, and an alkaline battery that contains this positive electrode active material. Aluminum and ytterbium are at least partially solid-dissolved in nickel hydroxide in the nickel composite hydroxide present in the positive electrode active material of the present invention.