Lithium-ion secondary battery

Patent metadata

Field	Value
Publication number	US-10833364-B2
Application number	US-201615572568-A
Country	US
Kind code	B2
Filing date	May 9, 2016
Priority date	May 11, 2015
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

Lithium ion secondary batteries are disclosed that include a positive electrode comprising a lithium nickel composite oxide as a positive electrode active material and a separator consisting of one or more layers selected from polyimide layer, polyamide layer, the battery having a low self-discharge failure rate even after long term storage. The lithium ion secondary batteries can include a positive electrode comprising a lithium nickel composite oxide and a separator consisting of one or more layers selected from polyimide layer, polyamide layer, and polyamide imide layer, wherein the battery comprises an acid and/or an acid anhydride in an electrolyte solution and/or a member in contact with the electrolyte solution.

First claim

The invention claimed is:

1. A lithium ion secondary battery comprising
a positive electrode comprising a positive electrode active material comprising a lithium nickel composite oxide represented by formula (A), wherein the content of the lithium nickel composite oxide represented by formula (A) in the positive electrode active material is 100 mass %, and the positive electrode further comprises lithium hydroxide, lithium carbonate and/or lithium hydrogen carbonate, and
a separator consisting of one or more layers selected from a polyimide layer, a polyamide layer, and a polyamide imide layer,
wherein the battery comprises an electrolyte solution, wherein the electrolyte solution comprises and acid anhydride in an amount of 0.1 mol/l or more and 3 mol/l or less,
Li y Ni (i-x) M x O 2   (A)

wherein 0≤x<0.5, 0<y≤1.2, and M is Co and Al.

2. The lithium ion secondary battery according to claim 1 , wherein the separator is a microporous membrane or a nonwoven fabric.

3. The lithium ion secondary battery according to claim 2 , wherein the separator is an aramid microporous membrane.

4. The lithium ion secondary battery according to claim 3 , wherein the separator is a microporous separator consisting of one aramid layer.

5. The lithium ion secondary battery according to claim 1 , wherein a packing density of the positive electrode is 3.0 g/cm 3 or more.

6. The lithium ion secondary battery according to claim 1 , wherein the acid anhydride is selected from the group consisting of succinic anhydride, tetrafluoro succinic anhydride and maleic anhydride.

7. The lithium ion secondary battery according to claim 1 , wherein x in the formula (A) is 0.2 or less.

8. The lithium ion secondary battery according to claim 1 , wherein the separator consists of an aramid.

9. The lithium ion secondary battery according to claim 8 , wherein the separator has a thickness of 25 μm or less.

10. The lithium ion secondary battery according to claim 9 , wherein the electrolyte solution comprises LiPF 6 and ethylene carbonate and diethyl carbonate.

11. A power storage device having the lithium ion secondary battery according to claim 1 .

12. A vehicle mounting the lithium-ion secondary battery according to claim 1 .

13. A method of producing a lithium ion secondary battery according to claim 1 having an electrode element, an electrolyte solution and an outer package, comprising:
a step of producing the electrode element by placing a positive electrode comprising a lithium nickel composite oxide and a negative electrode so as to be faced with each other via a separator consisting of one or more layers selected from a polyimide layer, a polyamide layer, and a polyamide imide layer, and
a step of enclosing the electrode element and the electrolyte solution in the outer package, wherein the electrolyte solution comprises an acid and/or an acid anhydride.

Assignees

• Nec Corp

Inventors

• Iriyama Jiro
• Shimura Kenichi
• Inoue Kazuhiko

Classifications

• H01M50/454

  comprising a non-fibrous layer and a fibrous layer superimposed on one another · CPC title

• H01M50/457

  comprising three or more layers · CPC title

• H01M50/491

  Porosity · CPC title

• H01M50/423

  Polyamide resins · CPC title

• H01M50/489

  Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties · CPC title