Electric double layer capacitor

Patent metadata

Field	Value
Publication number	US-10636581-B2
Application number	US-201615760969-A
Country	US
Kind code	B2
Filing date	Jun 17, 2016
Priority date	Jun 17, 2016
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

This electric double layer capacitor is an electric double layer capacitor capable of maintaining a discharge capacity retention rate of 80% or more in a constant current and constant voltage continuous charge test at 60° C. and 3.5 V for 1,000 hours or more,
wherein a positive electrode includes graphite as a positive-electrode active material, a current collector on the positive electrode side is an aluminum material, the aluminum material is coated with an amorphous carbon film, and the amorphous carbon film has a thickness in the range from 60 nm or more to 300 nm or less.

First claim

The invention claimed is:

1. An electric double layer capacitor capable of maintaining a discharge capacity retention rate of 80% or more in a constant current and constant voltage continuous charge test at 60° C. and 3.5 V for 1,000 hours or more, wherein
a positive electrode includes a positive-electrode active material layer and a current collector in a positive electrode side, and the positive-electrode active material layer arranged on the current collector,
the positive-electrode active material layer includes graphite as a positive electrode active material,
the current collector on the positive electrode side is an aluminum material,
the aluminum material is coated exclusively with a film composed of an amorphous carbon and one or more optional element selected from a group consisting of boron and nitrogen, and
the amorphous carbon film has a thickness in a range from 60 nm or more to 300 nm or less.

2. The electric double layer capacitor according to claim 1 ,
wherein a current collector on a negative electrode side is any one of materials selected from the group consisting of an aluminum material, etched aluminum, and an aluminum material coated with an amorphous carbon film.

3. The electric double layer capacitor according to claim 1 , wherein the graphite comprises a rhombohedral crystal.

4. The electric double layer capacitor according to claim 1 ,
wherein a negative electrode comprises a carbonaceous material selected from the group consisting of activated carbon, graphite, hard carbon and soft carbon as a negative-electrode active material.

5. The electric double layer capacitor according to claim 2 , wherein the graphite comprises a rhombohedral crystal.

6. The electric double layer capacitor according to claim 2 ,
wherein a negative electrode comprises a carbonaceous material selected from the group consisting of activated carbon, graphite, hard carbon and soft carbon as a negative-electrode active material.

7. The electric double layer capacitor according to claim 3 ,
wherein a negative electrode comprises a carbonaceous material selected from the group consisting of activated carbon, graphite, hard carbon and soft carbon as a negative-electrode active material.

8. The electric double layer capacitor according to claim 5 ,
wherein a negative electrode comprises a carbonaceous material selected from the group consisting of activated carbon, graphite, hard carbon and soft carbon as a negative-electrode active material.

9. The electric double layer capacitor according to claim 1 ,
wherein the amorphous carbon film is one or more selected from a group consisting of a diamond-like carbon film, a hard carbon film, an a-C film, and an a-C:H film.

10. The electric double layer capacitor according to claim 1 ,
wherein the amorphous carbon film is one or more selected from a group consisting of a diamond-like carbon film, an a-C film, and an a-C:H film.

11. The electric double layer capacitor according to claim 1 ,
wherein the amorphous carbon film is a diamond-like carbon film in which boron or nitrogen is preferably doped.

Assignees

• Tpr Co Ltd
• Toc Capacitor Co Ltd
• Yoshio Masaki

Inventors

• Kobayashi Naoya
• Yoshio Masaki

Classifications

• H01G11/28 Primary

  arranged or disposed on a current collector; Layers or phases between electrodes and current collectors, e.g. adhesives · CPC title

• H01G11/32

  Carbon-based · CPC title

• H01G11/50

  specially adapted for lithium-ion capacitors, e.g. for lithium-doping or for intercalation · CPC title

• Y02E60/13

  Energy storage using capacitors · CPC title

• H01G11/06 Primary

  with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC] · CPC title