Li-Ni composite oxide particles and process for producing the same, and non-aqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-9698420-B2
Application number	US-201314436244-A
Country	US
Kind code	B2
Filing date	Oct 15, 2013
Priority date	Oct 17, 2012
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

The present invention relates to Li-Ni composite oxide particles that exhibit a high initial discharge capacity and are excellent in thermal stability when used as a positive electrode active substance for non-aqueous electrolyte secondary batteries, and a process for producing the Li-Nicomposite oxide particles. The Li-Ni composite oxide particles of the present invention have a composition of Li x Ni 1−y−a−b Co y M1 a M2 b O 2 wherein x, y, a and b represent 1.00≦x≦1.10; 0<y≦0.25; 0<a≦0.25; and 0≦b≦0.10, respectively; M1 is at least one element selected from the group consisting of Al and Mn; and M2 is at least one element selected from the group consisting of Zr and Mg, in which a product of a metal occupancy (%) of lithium sites of the Li-Ni composite oxide as determined by Rietveld analysis of X-ray diffraction thereof and a crystallite size (nm) of the Li-Ni composite oxide as determined by the Rietveld analysis is not less than 700 and not more than 1400.

First claim

The invention claimed is:

1. Li-Ni composite oxide particles having a composition of Li x Ni 1−y−a−b Co y M1 a M2 b O 2 wherein x, y, a and b represent 1.00≦x≦1.10; 0<y≦0.25; 0<a≦0.25; and 0≦b≦0.10, respectively; M1 is at least one element selected from the group consisting of Al and Mn; and M2 is at least one element selected from the group consisting of Zr and Mg, a product of a metal occupancy (%) of lithium sites of the Li-Nicomposite oxide as determined by Rietveld analysis of X-ray diffraction thereof and a crystallite size (nm) of the Li-Ni composite oxide as determined by the Rietveld analysis being not less than 700 and not more than 1400.

2. The Li-Ni composite oxide particles according to claim 1 , wherein the metal occupancy of lithium sites of the Li-Ni composite oxide as determined by the Rietveld analysis is not less than 2% and not more than 7%.

3. The Li-Ni composite oxide particles according to claim 1 , wherein the crystallite size of the Li-Ni composite oxide as determined by the Rietveld analysis is not more than 500 nm.

4. The Li-Ni composite oxide particles according to claim 1 , wherein the Li-Ni composite oxide particles have an average particle diameter of 1 to 20 μm and a BET specific surface area of 0.1 to 1.6 m 2 /g.

5. A process for producing the Li-Ni composite oxide particles as claimed in claim 1 , comprising the steps of mixing lithium compound particles and Ni-Co hydroxide particles, and calcining the resulting mixture, the Ni-Co hydroxide particles being produced by mixing an aqueous solution of a sulfuric acid salt of each metal element, an ammonia aqueous solution and a sodium hydroxide aqueous solution such that an ammonia concentration in a reaction vessel is controlled to not more than 1.4 mol/L, and a ratio of the ammonia concentration in the reaction vessel to a surplus hydroxyl group concentration in the reaction vessel is controlled to not less than 6.

6. A process for producing the Li-Ni composite oxide particles as claimed in claim 1 , comprising the steps of mixing lithium compound particles, Ni-Co hydroxide particles, and aluminum compound particles and/or zirconium compound particles, and calcining the resulting mixture, the Ni-Cohydroxide particles being produced by mixing an aqueous solution of a sulfuric acid salt of each metal element, an ammonia aqueous solution and a sodium hydroxide aqueous solution such that an ammonia concentration in a reaction vessel is controlled to not more than 1.4 mol/L, and a ratio of the ammonia concentration in the reaction vessel to a surplus hydroxyl group concentration in the reaction vessel is controlled to not less than 6.

7. A non-aqueous electrolyte secondary battery using a positive electrode comprising a positive electrode active substance comprising the Li-Nicomposite oxide particles as claimed in claim 1 .

Assignees

• Toda Kogyo Corp

Inventors

• Ishizaki Kazutoshi
• Kikuya Kazuhiko
• Sugihara Takahiko
• Santoki Teruaki
• Harada Takamitsu
• Nishimura Masaki
• Mishima Yuji
• Sadamura Hideaki

Classifications

• H01M10/052

  Li-accumulators · CPC title

• C01P2004/03

  obtained by SEM · CPC title

• C01G53/50

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

• C01P2006/12

  Surface area · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title