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: Provided is a nickel composite hydroxide that was excellent in reactivity to a lithium compound and a positive electrode active material using the nickel composite hydroxide as a precursor. The nickel composite hydroxide, having an average diameter of pores of 50 ? or larger and 60 ? or smaller in pore distribution measurement by a nitrogen adsorption method and an integrated intensity ratio of a diffraction peak appearing in a range of 2?=51.9±1.0°/a diffraction peak appearing in a range of 2?=19.1±1.0° in powder X-ray diffraction using CuK? rays of 0.40 or more and 0.50 or less.

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.