Lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-10177413-B2
Application number	US-201314443719-A
Country	US
Kind code	B2
Filing date	Nov 18, 2013
Priority date	Nov 20, 2012
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

The present invention is a lithium ion secondary battery comprising a positive electrode and a non-aqueous electrolyte solution comprising a non-aqueous electrolyte solvent, wherein the positive electrode comprises a positive electrode active material having an operating potential at 4.5 V or higher versus lithium metal, the non-aqueous electrolyte solvent comprises a fluorinated phosphate ester represented by a predetermined formula and at least one selected from the group consisting of sulfone compounds represented by predetermined formulae, and the sulfone compound is included in an amount of 5 volume % or more in the non-aqueous electrolyte solvent.

First claim

The invention claimed is:

1. A lithium ion secondary battery comprising:
a positive electrode,
a separator,
an outer package comprising a laminate film, and
a non-aqueous electrolyte solution comprising a non-aqueous electrolyte solvent, wherein:
the positive electrode comprises a positive electrode active material having an operating potential of 4.5 V or higher versus lithium metal,
the separator comprises a polyolefin, and
the non-aqueous electrolyte solvent comprises:
a fluorinated phosphate ester represented by the following formula (1);
a sulfone compound selected from the group consisting of a compound represented by the following formula (2) and a compound represented by the following formula (3);

a fluorinated ether represented by the following formula (4); and
a cyclic carbonate, wherein the sulfone compound is included in an amount of 5 volume % or more in the non-aqueous electrolyte solvent, and in the non-aqueous electrolyte solvent, the volume ratio of the cyclic carbonate (CC), the sulfone compound (SF), the fluorinated phosphate ester (FP), and the fluorinated ether (FE) is in a range of CC:SF:FP:FE=5 to 15:15 to 25:10 to 30:40 to 60:

wherein R 1 , R 2 , R 3 each independently represent alkyl group or fluorinated alkyl group, and at least one thereof is fluorinated alkyl group,

wherein R 1 and R 2 each independently represent substituted or unsubstituted alkyl group,

wherein R 3 represents substituted or unsubstituted alkylene group,
R 101 —O—R 102   (4)

wherein R 101 and R 102 of formula (4) each represent an alkyl group or a fluorinated alkyl group, and at least one of R 101 and R 102 of formula (4) is the fluorinated alkyl group.

2. The lithium ion secondary battery according to claim 1 , wherein the sulfone compound comprises sulfolane.

3. The lithium ion secondary battery according to claim 1 , wherein the cyclic carbonate comprises at least one of ethylene carbonate (EC) and propylene carbonate (PC).

4. The lithium ion secondary battery according to claim 3 , wherein in the cyclic carbonate, the volume ratio between ethylene carbonate (EC) and propylene carbonate (PC) is in a range of EC:PC=100:0 to 50:50.

5. The lithium ion secondary battery according to claim 1 ,
wherein the non-aqueous electrolyte solution further comprises an additive,
wherein the additive comprises at least one selected from a cyclic monosulfonic acid ester, a cyclic disulfonic acid ester, a compound including an N(SO 2 F) 2 anion (FSI anion), and a fluorinated carbonate.

6. The lithium ion secondary battery according to claim 5 , wherein the additive is included at 0.1 to 3% by mass in relation to the total mass of the non-aqueous electrolyte solution.

7. The lithium ion secondary battery according to claim 5 , wherein the additive comprises one or more selected from 1,3-propane sultone, methylenemethane disulfonic acid ester, lithium bis(fluorosulfonyl)imide (LiFSI), and fluoroethylene carbonate (FEC).

8. The lithium ion secondary battery according to claim 5 , wherein the additive comprises two or more compounds selected from a cyclic monosulfonic acid ester, a cyclic disulfonic acid ester, a compound including an N(SO 2 F) 2 anion (FSI anion), and a fluorinated carbonate.

9. The lithium ion secondary battery according to claim 1 , wherein the positive electrode active material is represented by the following formula (6):
Li a (M x Mn 2-x-y A y )(O 4-w Z w )  (6)

wherein 0.4≤x≤1.2, 0≤y, x+y<2, 0≤a≤1.2, 0≤w≤1, M is at least one selected from the group consisting of Co, Ni, Fe, Cr, and Cu, A is at least one selected from the group consisting of Li, B, Na, Mg, Al, Ti, Si, K, and Ca, and Z is at least one of F and Cl.

10. The lithium ion secondary battery according to claim 1 , further comprising a negative electrode,
wherein the negative electrode comprises:
a water-based binder using a water-based emulsion; and
carboxymethylcellulose (CMC) and/or a derivative thereof.

11. A method of producing a lithium ion secondary battery comprising an electrode element, an electrolyte solution, a separator and an outer package comprising a laminate film, comprising:
preparing an electrode element by placing a positive electrode and a negative electrode so as to face each other; and
encapsulating the electrode element and a non-aqueous electrolyte solution comprising a non-aqueous electrolyte solvent in the outer package,
wherein:
the positive electrode comprises a positive electrode active material which is capable of absorbing and releasing lithium, and operates at 4.5 V or higher versus lithium,
the separator comprises a polyolefin, and
the non-aqueous electrolyte solvent comprises:
a fluorinated phosphate ester represented by the formula (1);
a sulfone compound selected from the group consisting of a compound represented by the formula (2) and a compound represented by the formula (3);

a fluorinated ether represented by the following formula (4); and
a cyclic carbonate,
wherein the sulfone compound is included in an amount of 5 volume % or more in the non-aqueous electrolyte solvent, and
in the non-aqueous electrolyte solvent, the volume ratio of the cyclic carbonate (CC), the sulfone compound (SF), the fluorinated phosphate ester (FP), and the fluorinated ether (FE) is in a range of CC:SF:FP:FE=5 to 15:15 to 25:10 to 30:40 to 60:

wherein R 1 , R 2 , R 3 each independently represent alkyl group or fluorinated alkyl group, and at least one thereof is fluorinated alkyl group,

wherein R 1 and R 2 each independently represent substituted or unsubstituted alkyl group,

wherein R 3 represents substituted or unsubstituted alkylene group,
R 101 —O—R 102   (4)

wherein R 101 and R 102 of formula (4) each represent an alkyl group or fluorinated alkyl group, and at least one of R 101 and R 102 of formula (4) is the fluorinated alkyl group.

12. A lithium ion secondary battery comprising:
a positive electrode,
a separator,
an outer package comprising a laminate film, and
a non-aqueous electrolyte solution comprising a non-aqueous electrolyte solvent, wherein:
the positive electrode comprises a positive electrode active material having an operating potential of 4.5 V or higher versus lithium metal,
the separator comprises a polyolefin and
the non-aqueous electrolyte solvent comprises:
a fluorinated phosphate ester represented by the following formula (1);
a sulfone compound selected from the group consisting of a compound represented by the following formula (2) and a compound represented by the following formula (3);

a fluorinated ether represented by the following formula (4); and
a cyclic carbonate; and
wherein the sulfone compound is included in an amount of 5 volume % or more in the non-aqueous electrolyte solvent; and
in the non-aqueous electrolyte solvent, the volume ratio of the cyclic carbonate (CC), the sulfone compound (SF), the fluorinated phosphate ester (FP), and the fluorinated ether (FE) is in a range of CC:SF:FP:FE=5 to 15: 20 to

Assignees

• Nec Corp

Inventors

• Sasaki Hideaki
• Noguchi Takehiro
• Katou Yuukou
• Takahashi Makiko

Classifications

• Y02T10/7011

  Cross-Sectional Technologies · mapped topic

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M10/0569 Primary

  characterised by the solvents · CPC title

• H01M4/505

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

• H01M4/131 Primary

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title