US 2015/0311511 A1 · COATED NICKEL HYDROXIDE POWDER FOR ALKALI SECONDARY BATTERY POSITIVE ELECTRODE ACTIVE MATERIAL AND METHOD OF PRODUCING SAME

Abstract

A coated nickel hydroxide powder that has improved dispersibility in a paste to inhibit agglomeration and can be densely packed in a three-dimensional metal porous body in the preparation of a positive electrode for alkaline secondary battery includes nickel hydroxide particles and a coating layer made of a cobalt compound and formed on a surface of the nickel hydroxide particles, wherein when 10 mL of water is added to 10 g of the coated nickel hydroxide powder to prepare a suspension, the suspension having a pH of 10.2 or higher (as measured at 25° C.). The coated nickel hydroxide powder obtained through a crystallization step and a coating step is washed in a washing step until an amount of ammonium ions eluted into a suspension obtained by adding 10 mL of water to 10 g of the coated nickel hydroxide powder becomes 0.35 mmol/L or less.

Claims10

Dependent claims

A coated nickel hydroxide powder for an alkaline secondary battery positive electrode active material, comprising:

core particles made of nickel hydroxide;
and
a coating layer made of a cobalt compound and formed on a surface of the core particles, wherein
when 10 mL of water is added to 10 g of the coated nickel hydroxide powder to prepare a suspension, the suspension has a pH of 10.2 or higher as measured at 25° C.

1 more element

A method for producing a coated nickel hydroxide powder for an alkaline secondary battery positive electrode active material, the method comprising:

a crystallization step in which an ammonium ion supplier-containing aqueous solution and an aqueous alkali solution are supplied to a nickel-containing aqueous solution to obtain nickel hydroxide particles crystallized out by neutralization as core particles;
a coating step in which a coating layer made of a cobalt compound is formed on a surface of the core particles to obtain a coated nickel hydroxide powder;
a washing step in which the coated nickel hydroxide powder is washed;
and
a drying step in which the coated nickel hydroxide powder after washing is dried, wherein
in the washing step, the coated nickel hydroxide powder is washed until an amount of ammonium ions eluted into a suspension obtained by adding 10 mL of water to 10 g of the coated nickel hydroxide powder becomes 0.35 mmol/L or less.

3 more elements

Dependencies are inferred from the claim text.

Coated nickel hydroxide powder for alkali secondary battery positive electrode active material and method of producing same

Life of this patent

Coated nickel hydroxide powder for alkali secondary battery positive electrode active material and method of producing same

Life of this patent

Abstract

Claims10