Positive electrode active material for non-aqueous electrolyte secondary battery comprising tungsten coating film, and non-aqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-11967713-B2
Application number	US-201917059306-A
Country	US
Kind code	B2
Filing date	May 29, 2019
Priority date	May 31, 2018
Publication date	Apr 23, 2024
Grant date	Apr 23, 2024

Abstract

The present invention relates to a positive electrode active material for non-aqueous electrolyte secondary battery, including lithium-nickel composite oxide particles having a layer structure of hexagonal system; and a lithium tungstate coating film disposed on a surface of secondary particles of the lithium-nickel composite oxide particles, wherein the positive electrode active material for non-aqueous electrolyte secondary battery includes, as metallic elements, lithium (Li), nickel (Ni), cobalt (Co), element M (M) which is at least one element selected from Mn, V, Mg, Mo, Nb, Ti, Ca, Cr, Zr, Ta, and Al, and tungsten (W), wherein a ratio of amount of substance in the metallic elements contained is Li:Ni:Co:M:W=a:1-x-y:x:y:z, wherein 0.97≤a≤1.25, 0≤x≤0.35, 0≤y≤0.35, and 0.005≤z≤0.030.

First claim

The invention claimed is:

1. A positive electrode active material for a non-aqueous electrolyte secondary battery, comprising:
lithium-nickel composite oxide particles having a layer structure of hexagonal system; and
a lithium tungstate coating film disposed on a surface of secondary particles of the lithium-nickel composite oxide particles,
wherein the positive electrode active material for the non-aqueous electrolyte secondary battery includes, as metallic elements, lithium (Li), nickel (Ni), cobalt (Co), element M (M) which is at least one element selected from Mn, V, Mg, Mo, Nb, Ti, Ca, Cr, Zr, Ta, and Al, and tungsten (W),
wherein a ratio of amount of substance in the metallic elements contained is Li:Ni:Co:M:W=a:1-x-y:x:y:z,
wherein 0.97≤a≤1.25, 0≤x≤0.35, 0≤y≤0.35, and 0.007≤z≤0.020,
wherein a ratio of a maximum tungsten concentration to an average tungsten concentration is 5 or more and 25 or less when a line analysis is performed by STEM-EDX on a particle cross-section of the positive electrode active material for the non-aqueous electrolyte secondary battery, and
wherein a volume resistivity of the positive electrode active material when compressed to 3.2 g/cc as determined by a powder resistivity measurement is 1.0×10 2 Ω·cm or more and 1.0×10 4 Ω·cm or less.

2. The positive electrode active material for the non-aqueous electrolyte secondary battery according to claim 1 , wherein a crystalline phase of the lithium tungstate on the surface of the secondary particles is at least one selected from 7Li 2 WO 4 ·4H 2 O, Li 2 WO 4 , and Li 4 WO 5 .

3. The positive electrode active material for the non-aqueous electrolyte secondary battery according to claim 1 ,
wherein a specific surface area as measured by a BET method is 0.2 m 2 /g or more and 0.8 m 2 /g or less.

4. The positive electrode active material for the non-aqueous electrolyte secondary battery according to claim 1 ,
wherein a volume average particle size Mv of the positive electrode active material for the non-aqueous electrolyte secondary battery is 5 μm or more and 20 μm or less.

5. A non-aqueous electrolyte secondary battery comprising:
the positive electrode active material for the non-aqueous electrolyte secondary battery of claim 1 .

Assignees

• Sumitomo Metal Mining Co

Inventors

• Koshika Yuki
• KANEDA Haruki
• Yokoyama Jun

Classifications

• 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

• H01M4/366

  as layered products · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/58

  of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates · CPC title