Power storage device, lithium-ion secondary battery, electric double layer capacitor and lithium-ion capacitor

Patent metadata

Field	Value
Publication number	US-9478368-B2
Application number	US-201414450786-A
Country	US
Kind code	B2
Filing date	Aug 4, 2014
Priority date	Jun 30, 2010
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

One object is to provide a power storage device including an electrolyte using a room-temperature ionic liquid which includes a univalent anion and a cyclic quaternary ammonium cation having excellent reduction resistance. Another object is to provide a high-performance power storage device. A room-temperature ionic liquid which includes a cyclic quaternary ammonium cation represented by a general formula (G1) below is used for an electrolyte of a power storage device. In the general formula (G1), one or two of R 1 to R 5 are any of an alkyl group having 1 to 20 carbon atoms, a methoxy group, a methoxymethyl group, and a methoxyethyl group. The other three or four of R 1 to R 5 are hydrogen atoms. A − is a univalent imide anion, a univalent methide anion, a perfluoroalkyl sulfonic acid anion, tetrafluoroborate (BF 4 − ), or hexafluorophosphate (PF 6 − ).

First claim

What is claimed is:

1. A power storage device comprising:
a positive electrode;
a negative electrode;
a separator;
an electrolyte salt; and
an ionic liquid represented by a general formula (G2)

wherein R 2 represents an alkyl group having 1 to 4 carbon atoms,
wherein R 1 represents a hydrogen atom,
wherein A − represents a univalent imide anion selected from (C n F 2n+1 SO 2 ) 2 N − (n=0 to 4), (C m F 2m+1 SO 3 ) − (m=0 to 4), and CF 2 (CF 2 SO 2 ) 2 N − , and
wherein the electrolyte salt includes a lithium ion.

2. The power storage device according to claim 1 , wherein the power storage device is a lithium-ion secondary battery.

3. The power storage device according to claim 1 , wherein the power storage device is a lithium-ion capacitor.

4. The power storage device according to claim 1 , wherein the A − is (FSO 2 ) 2 N − or (CF 3 SO 2 ) 2 N − .

5. The power storage device according to claim 1 , the power storage device further comprising:
a first solvent,
wherein the first solvent is a room-temperature ionic liquid other than the ionic liquid represented by the general formula (G2).

6. An electronic appliance comprising the power storage device according to claim 1 .

7. An electric propulsion vehicle comprising the power storage device according to claim 1 .

8. A power storage device comprising:
a positive electrode;
a negative electrode;
a separator;
an electrolyte salt; and
an ionic liquid represented by a general formula (G4)

wherein A − represents a univalent imide anion selected from (C n F 2n+1 SO 2 ) 2 N − (n=0 to 4), (C m F 2m+1 SO 3 ) − (m=0 to 4), and CF 2 (CF 2 SO 2 ) 2 N − , and
wherein the electrolyte salt includes a lithium ion.

9. The power storage device according to claim 8 , wherein the power storage device is a lithium-ion secondary battery.

10. The power storage device according to claim 8 , wherein the power storage device is a lithium-ion capacitor.

11. The power storage device according to claim 8 , wherein the A − is (FSO 2 ) 2 N − or (CF 3 SO 2 ) 2 N − .

12. The power storage device according to claim 8 , the power storage device further comprising:
a first solvent,
wherein the first solvent is a room-temperature ionic liquid other than the ionic liquid represented by the general formula (G4).

13. An electronic appliance comprising the power storage device according to claim 8 .

14. An electric propulsion vehicle comprising the power storage device according to claim 8 .

Assignees

• Semiconductor Energy Lab

Inventors

• Ito Kyosuke
• Itakura Toru

Classifications

• Y02E60/13

  Energy storage using capacitors · CPC title

• H01G11/58 Primary

  Liquid electrolytes · CPC title

• H01M2300/0034

  Fluorinated solvents · CPC title

• H01M10/0566

  Liquid materials · CPC title

• H01G11/62 Primary

  characterised by the solute, e.g. salts, anions or cations therein · CPC title