Capacitor and method for producing the same

Patent metadata

Field	Value
Publication number	US-2016284479-A1
Application number	US-201415037987-A
Country	US
Kind code	A1
Filing date	Oct 24, 2014
Priority date	Nov 19, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

A capacitor includes an electrode group that includes a positive electrode including a positive electrode active material and a porous positive electrode current collector that holds the positive electrode active material, a negative electrode including a negative electrode active material and a porous negative electrode current collector that holds the negative electrode active material, and a first separator disposed between the positive electrode and the negative electrode; a nonaqueous electrolyte having alkali metal ion conductivity; a case that hermetically seals the electrode group and the nonaqueous electrolyte; an alkali metal supply source disposed between the electrode group and the case; and a second separator disposed between the electrode group and the alkali metal supply source. At least the negative electrode contains an alkali metal introduced by pre-doping using the alkali metal supply source. The second separator has a thickness of 5 to 60 μm. The negative electrode current collector includes a first metal porous body having a three-dimensional mesh-like structure.

First claim

1 . A capacitor comprising:
an electrode group that includes
a positive electrode including a positive electrode active material and a porous positive electrode current collector that holds the positive electrode active material,
a negative electrode including a negative electrode active material and a porous negative electrode current collector that holds the negative electrode active material, and
a first separator disposed between the positive electrode and the negative electrode;
a nonaqueous electrolyte having alkali metal ion conductivity; a case that hermetically seals the electrode group and the nonaqueous electrolyte; an alkali metal supply source disposed between the electrode group and the case; and a second separator disposed between the electrode group and the alkali metal supply source, wherein at least the negative electrode contains an alkali metal introduced by pre-doping using the alkali metal supply source, the second separator has a thickness of 5 to 60 μm, and the negative electrode current collector includes a first metal porous body having a three-dimensional mesh-like structure.

2 . The capacitor according to claim 1 , wherein the negative electrode has a thickness of 50 to 600 μm.

3 . The capacitor according to claim 1 , wherein the positive electrode current collector includes a second metal porous body having a three-dimensional mesh-like structure.

4 . The capacitor according to claim 1 , wherein the first separator has a porosity of 20% to 85%, and the second separator has a porosity of 20% to 85%.

5 . The capacitor according to claim 1 , wherein a ratio of a thickness of the first separator to a total thickness of a pair of the positive electrode and the negative electrode is 10% or less.

6 . The capacitor according to claim 1 , wherein, in a discharged state, the negative electrode has a potential of 0 to 1 V with respect to an oxidation-reduction potential of the alkali metal.

7 . A method for producing a capacitor, comprising:
a step of preparing an electrode group that includes a positive electrode including a positive electrode active material and a porous positive electrode current collector that holds the positive electrode active material, a negative electrode including a negative electrode active material and a porous negative electrode current collector that holds the negative electrode active material, and a first separator disposed between the positive electrode and the negative electrode;
a step of preparing an alkali metal supply source that supports an alkali metal;
a step of housing the alkali metal supply source, the electrode group, and a second separator in a case so that the alkali metal supply source is disposed between the electrode group and the case and faces the electrode group with the second separator therebetween;
a step of electrically connecting the negative electrode to the alkali metal supply source;
a step of pre-doping at least the negative electrode with the alkali metal supported on the alkali metal supply source by pouring a nonaqueous electrolyte having alkali metal ion conductivity into the case; and
a step of hermetically sealing the case,
wherein the second separator has a thickness of 5 to 60 μm, and
the negative electrode current collector includes a first metal porous body having a three-dimensional mesh-like structure.

8 . The method for producing a capacitor according to claim 7 , wherein the pre-doping is performed until a potential of the negative electrode reaches 0 to 1 V with respect to an oxidation-reduction potential of the alkali metal.

Assignees

• Sumitomo Electric Industries

Inventors

• Okuno Kazuki
• Majima Masatoshi
• Ueda Mitsuyasu

Classifications

• H01G11/78

  Cases; Housings; Encapsulations; Mountings · 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

• H01G11/70

  characterised by their structure · CPC title

• H01G11/84

  Processes for the manufacture of hybrid or EDL capacitors, or components thereof · CPC title

• H01G11/52

  Separators · CPC title