Sumitomo Metal Mining Company, Ltd.

Tai Ito

Norimichi Yonesato

Kazuomi Ryoshi

Hiroyuki Toya

Tetsufumi Komukai

Mitsuru Yamauchi

Shoji Futaki

A nickel composite hydroxide includes nickel, cobalt, manganese, and an element M with an atomic ratio of Ni:Co:Mn:M=1−x1−y1−z1:x1:y1:z1 (wherein M is at least one element selected from a group consisting of a transition metal element other than Ni, Co, Mn, a II group element, and a XIII group element, 0.15≤0.25, 0.15≤y1≤0.25, 0≤z1≤0.1), the nickel composite hydroxide having a cobalt or manganese rich layer from a surface of a particle of the secondary particles toward an inside of the secondary particles and a layered low-density layer between the cobalt or manganese rich layer and a center of the particle of the secondary particles, and a thickness of the cobalt or manganese rich layer and low-density layer is 1% or more and 10% or less to a diameter of the secondary particles.

Nickel composite hydroxide, method for producing nickel composite hydroxide, positive electrode active material for lithium ion secondary battery, method for producing positive electrode active material for lithium ion secondary battery, and lithium ion secondary battery

Disclosed herein are a nickel oxide fine powder that is suitable as a material for electronic parts and has a controlled sulfur content, a low chlorine content, and a fine particle size and a method for industrially and stably producing such a nickel oxide fine powder. Nickel hydroxide obtained by neutralizing an aqueous nickel sulfate solution with an alkali is heat-treated in a non-reducing atmosphere at a temperature higher than 850&#xb0; C. but lower than 1050&#xb0; C. to form nickel oxide particles, and a sintered compact of nickel oxide particles that may be formed during the heat treatment is pulverized by preferably allowing the nickel oxide particles to collide with one another. The thus obtained nickel oxide fine powder has a sulfur content of 400 mass ppm or less, a chlorine content of 50 mass ppm or less, a sodium content of 100 mass ppm or less, and a specific surface area of 3 m/g or more but less than 6 m/g.

Nickel oxide micropowder and method for producing same

Nickel hydroxide obtained by neutralizing an aqueous nickel sulfate solution with an alkali is heat-treated in a non-reducing atmosphere at a temperature higher than 850&#xb0; C. but lower than 1050&#xb0; C. to form nickel oxide particles, and a sintered compact of nickel oxide particles that may be formed during the heat treatment is pulverized by preferably allowing the nickel oxide particles to collide with one another. The thus obtained nickel oxide fine powder has a sulfur content of 400 mass ppm or less, a chlorine content of 50 mass ppm or less, a sodium content of 100 mass ppm or less, and a specific surface area of 3 m/g or more but less than 6 m/g.

This invention provides a nickel oxide powder material, a production process thereof with high efficiency, a raw material composition for use in the same, and an anode material using the nickel oxide powder material. The nickel oxide powder material, when used as an anode material for a solid oxide fuel cell, can reduce heat shrinkage percentage in calcination to reduce a shrinkage difference from other component, and can suppress the occurrence of cracking, delamination, warpage and the like during calcining. Also in power generation after re-reduction after exposure of the anode once to an oxidizing atmosphere, for example, due to the disruption of the fuel supply, deterioration of microstructure of the anode can be suppressed, and the voltage drop percentage of the cell can be reduced. The nickel oxide powder material is used in an anode material constituting a solid oxide fuel cell and is characterized in that spinel compound represented by compositional formula: NiMOwherein M represents a metal element is formed inside or on the surface of the nickel oxide powder or at the interface between the powder particles.

Nickel oxide powder material for solid oxide fuel cell, production process thereof, raw material composition for use in the same, and anode material using the nickel oxide powder material

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Niihama, Japan

Tai Ito