Nickel-containing composite hydroxide and production process therefor, positive-electrode active material for a nonaqueous-electrolyte secondary battery and production process therefor, and nonaqueous-electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-2017324090-A1
Application number	US-201515522852-A
Country	US
Kind code	A1
Filing date	Oct 29, 2015
Priority date	Oct 30, 2014
Publication date	Nov 9, 2017
Grant date	—

Abstract

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 2 /g. Thus a nickel-containing composite hydroxide expressed by Ni 1−x−y Co x Al y M t (OH) 2+α (where, 0<x≦0.20, 0<y≦0.15, 0≦t≦0.10, 0≦α 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 1−x−z Co x Mn z M t (OH) 2+α (where 0<x≦0.50, 0<z≦0.50, x+z≦0.70, 0≦t≦0.10, 0≦α≦0.50, and M is one or more kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y) is obtained.

First claim

1 . A nickel-containing composite hydroxide that is expressed by the general formula: Ni 1−x−y Co x Al y M t (OH) 2+α (where, 0<x≦0.20, 0<y≦0.15, 0≦t≦0.10, 0≦α 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 1−x−z Co x Mn z M t (OH) 2+α (where 0<x≦0.50, 0<z≦0.50, x+z≦0.70, 0≦t≦0.10, 0≦α≦0.50, and M is one or more kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y), and includes secondary particles that are formed from an aggregation of plural primary particles, with the average particle size of the secondary particles being 20 μm to 50 μm, and the average particle size of the primary particles being 0.01 μm to 0.40 μm, and when roasted in air for 2 hours at 800° C., the BET value of the nickel-containing composite oxide that is obtained is 12 m 2 /g to 50 m 2 /g.

2 . The nickel-containing composite hydroxide according to claim 1 , wherein the shape of the secondary particles is spherical or ellipsoidal.

3 . A production method for a nickel-containing composite hydroxide is a method for producing a nickel-containing composite hydroxide that is expressed by the general formula: Ni 1−x−y Co x Al y M t (OH) 2+α (where, 0<x≦0.20, 0<y≦0.15, 0≦t≦0.10, 0≦α≦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 1−x−z Co x Mn z M t (OH) 2+α (where 0<x≦0.50, 0<z≦0.50, x+z≦0.70, 0≦t≦0.10, 0≦α≦0.50, and M is one or more kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y) by a crystallization reaction; and
when performing the crystallization reaction
adds an alkaline aqueous solution to a mixed aqueous solution that includes at least nickel and cobalt to make the pH value of that mixed aqueous solution that is measured at a reference liquid temperature of 25° C. 11.0 to 13.0;
makes the reaction temperature of the mixed aqueous solution 20° C. to 45° C.;
adds a complexing agent to the mixed aqueous solution to make the ammonium ion concentration of that mixed aqueous solution 4 g/L to 15 g/L; and
using stirring blades that have an inclination angle with respect to a horizontal plane of no less than 20° and no greater than 60°, stirs the mixed solution according to stirring conditions so that the BET value of nickel-containing composite oxide that is obtained by roasting the nickel-containing composite hydroxide in air for 2 hours at 800° C. becomes 12 m 2 /g to 50 m 2 /g.

4 . The production method for nickel-containing composite hydroxide according to claim 3 , further comprising a process of covering the nickel-containing composite hydroxide that is obtained by the crystallization reaction with Al or Mn, or with Al or Mn and added elements M.

5 . A positive-electrode active material for a nonaqueous-electrolyte secondary battery that comprises a lithium nickel-containing composite oxide that is expressed by the general formula: Li 1+u Ni 1−x−y Co x Al y M t O 2 (where 0<x≦0.20, 0<y≦0.15, 0≦t≦0.10, 0≦u≦0.50, and M is at least one kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y), or Li 1+u Ni 1−x−z Co x Mn z M t O 2 (where 0<x≦0.50, 0<z≦0.50, x+z≦0.70, 0≦t≦0.10, 0≦u≦0.50, and M is at least one kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y), and includes secondary particles that are formed by an aggregation of plural primary particles, and has a layered hexagonal crystal structure; and
the average particle size of the secondary particles is 20 μm to 50 μm, the average particle size of the primary particles is 0.10 μm to 0.40 μm, and the site occupancy of metal ions other than lithium ions at site 3 a that is obtained from Rietveld analysis of X-ray diffraction is 1.5% or less.

6 . The positive-electrode active material for a nonaqueous-electrolyte secondary battery according to claim 5 , wherein the shape of the secondary particles is spherical or ellipsoidal.

7 . The positive-electrode active material for a nonaqueous-electrolyte secondary battery according to claim 5 , wherein the tap density of the secondary particles is 2.5 g/cm 3 or greater.

8 . A production method for a positive-electrode active material for a nonaqueous-electrolyte secondary battery that is a production method for a positive-electrode active material that comprises a lithium nickel-containing composite oxide that has a layered hexagonal crystal structure that is expressed by the general formula: Li 1+u Ni 1−x−y Co x Al y M t O 2 (where 0<x≦0.20, 0<y≦0.15, 0≦t≦0.10, 0≦u≦0.50, and M is at least one kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y), or Li 1+u Ni 1−x−z Co x Mn z M t O 2 (where 0<x≦0.50, 0<z≦0.50, x+z≦0.70, 0≦t≦0.10, 0≦u≦0.50, and M is at least one kind of element selected from among Mg, Ca, Ba, Nb, Mo, V, Ti, Zr and Y);
the method comprising;
a mixing process for forming a lithium mixture by mixing the nickel-containing composite hydroxide according to claim 1 or heat treated particles of that nickel-containing composite hydroxide with a lithium compound; and
a firing process of performing firing of the lithium mixture that was formed in the mixing process in an oxygen atmosphere at a temperature of 650° C. to 850° C.

9 . The production method for a positive-electrode active material for a nonaqueous-electrolyte secondary battery according to claim 8 , further comprising a roasting process before the mixing process for obtaining the heat treated particles by roasting the nickel-containing composite hydroxide in an air atmosphere at 400° C. to 900° C.

10 . A nonaqueous-electrolyte secondary battery that uses the positive-electrode active material for a nonaqueous-electrolyte secondary battery according to claim 5 as positive-electrode material.

Assignees

• Sumitomo Metal Mining Co

Inventors

• Ryoshi Kazuomi
• Mori Kensaku
• Kase Katsuya
• Kamata Yasutaka

Classifications

• C01P2006/11

  Powder tap density · CPC title

• C01G53/66

  containing alkaline earth metals, e.g. SrNiO3 or SrNiO2 · CPC title

• C01G53/50

  of the type (MnO2)n-, e.g. Li(NixMn1-x)O2 or Li(MyNixMn1-x-y)O2 · CPC title

• C01P2006/40

  Electric properties · CPC title

• H01M4/525 Primary

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title