Lithium nickelate-based positive electrode active substance particles and process for producing the same, and non-aqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-10615414-B2
Application number	US-201615386406-A
Country	US
Kind code	B2
Filing date	Dec 21, 2016
Priority date	Jan 15, 2016
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

The present invention provides lithium nickelate-based positive electrode active substance particles having a high energy density which are excellent in charge/discharge cycle characteristics when highly charged, and hardly suffer from generation of gases upon storage under high-temperature conditions, and a process for producing the positive electrode active substance particles, as well as a non-aqueous electrolyte secondary battery. The present invention relates to positive electrode active substance particles each comprising a core particle X comprising a lithium nickelate composite oxide having a layer structure which is represented by the formula: Li1+aNi1-b-cCobMcO2 wherein M is at least one element selected from the group consisting of Mn, Al, B, Mg, Ti, Sn, Zn and Zr; a is a number of −0.1 to 0.2 (−0.1≤a≤0.2); b is a number of 0.05 to 0.5 (0.05≤b≤0.5); and c is a number of 0.01 to 0.4 (0.01≤c≤0.4); a coating compound Y comprising at least one element selected from the group consisting of Al, Mg, Zr, Ti and Si; and a coating compound Z comprising an Li element, in which a content of lithium hydroxide LiOH in the positive electrode active substance particles is not more than 0.40% by weight, a content of lithium carbonate Li2CO3 in the positive electrode active substance particles is not more than 0.65% by weight, and a weight ratio of the content of lithium carbonate to the content of lithium hydroxide is not less than 1.

First claim

The invention claimed is:

1. Positive electrode active substance particles each comprising:
a core particle X comprising a lithium nickelate composite oxide having a layer structure which is represented by the formula:
Li 1+a Ni 1-b-c Co b M c O 2

wherein M is at least one element selected from the group consisting of Mn, Al, B, Mg, Ti, Sn, Zn and Zr; and wherein:
−0.1≤a≤0.2;
0.05≤b≤0.5; and
0.01≤c≤0.4;

a coating compound Y comprising at least one element selected from the group consisting of Al, Mg, Zr, Ti and Si, wherein compound Y comprises an oxide, carbonate, or hydroxide; and
a coating compound Z comprising an Li element, wherein coating compound Z comprises an oxide, carbonate, or hydroxide,
in which a content of lithium hydroxide (LiOH) in the coating compound Z is 0 to 0.40% by weight, a content of lithium carbonate (Li 2 CO 3 ) in the coating compound Z is 0 to 0.65% by weight, and a weight ratio of the content of lithium carbonate to the content of lithium hydroxide in the coating compound Z is not less than 1 and not greater than 3.42,
wherein coating compound Y and coating compound Z are separate coating compounds.

2. The positive electrode active substance particles according to claim 1 , wherein a weight ratio of the coating compound Z to the coating compound Y is in the range of 1 to 100.

3. The positive electrode active substance particles according to claim 1 , wherein the positive electrode active substance particles have a BET specific surface area of 0.05 to 0.70 m 2 /g, a median diameter D 50 of aggregated particles of 1 to 30 μm, and a 2% powder pH value of not more than 11.40.

4. A non-aqueous electrolyte secondary battery comprising a positive electrode active substance comprising the positive electrode active substance particles as claimed in claim 1 .

5. A process for producing the positive electrode active substance particles as claimed in claim 1 , comprising the steps of:
forming the coating compound Y on a surface of the core particle X by a vapor phase epitaxy method; and then
subjecting the resulting particle to humidification treatment and heat treatment in atmospheric air at a temperature of 150 to 450° C. to form the coating compound Z on the particle.

6. A process for producing the positive electrode active substance particles as claimed in claim 1 , comprising the steps of:
subjecting the core particle X to humidification treatment and heat treatment in atmospheric air at a temperature of 150 to 450° C. to form the coating compound Z on a surface of the core particle X; and then
forming the coating compound Y on the resulting particle by a vapor phase epitaxy method.

Assignees

• Toda Kogyo Corp

Inventors

• Watanabe Hiroyasu
• Sun Xiang

Classifications

• H01M4/483

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M10/052

  Li-accumulators · CPC title

• C23C16/45527

  characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations · CPC title

• C23C16/45553

  characterized by the use of precursors specially adapted for ALD · CPC title