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

• US 8,795,544 B2
• Filed: 06/23/2011
• Issued: 08/05/2014
• Est. Priority Date: 06/30/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Ito, Kyosuke, Itakura, Toru
• Primary Examiner(s): Koslow, Carol M
• Application Number:
  US13/167,030
• Publication Number:
  US 20120002349A1
• Time in Patent Office: 1,139 Days
• Field of Search: 252/62.2, 361/503, 361/502, 361/505, 429/339, 429/324
• US Class Current: 252/62.2
• CPC Class Codes: H01G 11/22 Electrodes
• CPC Class Codes: H01G 11/58 Liquid electrolytes
• CPC Class Codes: H01G 11/62 characterised by the solute, e.g. salts, anions or cations therein
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0561 the electrolyte being constituted of inorganic materials only
• CPC Class Codes: H01M 10/0563 Liquid materials, e.g. for Li-SOCl2 cells
• CPC Class Codes: H01M 10/0566 Liquid materials
• CPC Class Codes: H01M 10/0569 characterised by the solvents
• CPC Class Codes: H01M 2300/0034 Fluorinated solvents
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

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 R₁ to R₅ 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 R₁ to R₅ are hydrogen atoms. A⁻ is a univalent imide anion, a univalent methide anion, a perfluoroalkyl sulfonic acid anion, tetrafluoroborate (BF₄⁻), or hexafluorophosphate (PF₆⁻).

Claims

1. A power storage device comprising:

a positive electrode;

a negative electrode;

a separator;

an electrolyte salt; and

a room-temperature ionic liquid represented by a general formula (G1)

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 (FSO₂)₂N⁻

or (CF₃SO₂)₂N⁻

.

5. A power storage device comprising:

a positive electrode;

a negative electrode;

a separator;

an electrolyte salt; and

a room-temperature ionic liquid represented by a general formula (G2)

6. The power storage device according to claim 5,

wherein the power storage device is a lithium-ion secondary battery.

7. The power storage device according to claim 5,

wherein the power storage device is a lithium-ion capacitor.

8. The power storage device according to claim 5, wherein the A⁻

is (FSO₂)₂N⁻

or (CF₃SO₂)₂N⁻

.

9. A power storage device comprising:

a positive electrode;

a negative electrode;

a separator;

an electrolyte salt; and

a room-temperature ionic liquid represented by a general formula (G3)

10. The power storage device according to claim 9,

wherein the power storage device is a lithium-ion secondary battery.

11. The power storage device according to claim 9,

wherein the power storage device is a lithium-ion capacitor.

12. The power storage device according to claim 9, wherein the A⁻

is (FSO₂)₂N⁻

or (CF₃SO₂)₂N⁻

.