Low resistance ultracapacitor electrode and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-9595398-B2
Application number	US-201414166494-A
Country	US
Kind code	B2
Filing date	Jan 28, 2014
Priority date	Aug 30, 2013
Publication date	Mar 14, 2017
Grant date	Mar 14, 2017

Abstract

A carbon-based electrode includes activated carbon, carbon black, and a binder. The binder is fluoropolymer having a molecular weight of at least 500,000 and a fluorine content of 40 to 70 wt. %. A method of forming the carbon-based electrode includes providing a binder-less conductive carbon-coated current collector, pre-treating the carbon coating with a sodium napthalenide-based solution, and depositing onto the treated carbon coating a slurry containing activated carbon, carbon black and binder.

First claim

We claim:

1. A carbon-based electrode comprising:
a current collector having opposing first and second major surfaces;
a first conductive layer disposed adjacent to the first major surface;
a second conductive layer disposed adjacent to the second major surface, wherein the first conductive layer and second conductive layer comprising a carbon coating, and are free of a binder material; and
a first carbon-based layer and a second carbon-based layer, each carbon-based layer comprising a mixture of activated carbon, carbon black, and a binder, and disposed adjacent to the respective first and second conductive layers, wherein the binder comprises a fluoro-polymer having from 40 to 70 wt. % fluorine and a molecular weight of at least 500,000, and
the carbon coating first and second conductive layers each have an organic content of less than 1 wt. %.

2. The carbon-based electrode according to claim 1 , wherein the fluoro-polymer includes 50 to 70 wt. % fluorine.

3. The carbon-based electrode according to claim 1 , wherein the fluoro-polymer has a molecular weight of at least 800,000.

4. The carbon-based electrode according to claim 1 , wherein the fluoro-polymer is polyvinylidene fluoride.

5. The carbon-based electrode according to claim 1 , wherein the carbon coating first and second conductive layers each have an organic content of less than 0.5 wt. %.

6. The carbon-based electrode according to claim 1 , wherein the first and second conductive layers are free of organic content.

7. The carbon-based electrode according to claim 1 , wherein the first and second conductive layers comprise thermally-grown carbon.

8. The carbon-based electrode according to claim 1 , wherein the first and second carbon-based layers have a thickness of from 20 to 500 micrometers.

9. The carbon-based electrode according to claim 1 , wherein the activated carbon has an average particle size of less than 20 microns.

10. The carbon-based electrode according to claim 1 , wherein the carbon-based layers include 75-90 wt. % activated carbon, 5-10 wt. % carbon black, and 5-15 wt. % binder.

11. An energy storage device comprising a first carbon-based electrode and a second carbon-based electrode arranged within a casing, wherein each carbon-based electrode includes:
a current collector having opposing first and second major surfaces;
a first conductive layer disposed adjacent to the first major surface;
a second conductive layer disposed adjacent to the second major surface, wherein the first conductive layer and second conductive layer comprise a carbon coating, and are free of a binder material; and
a first carbon-based layer and a second carbon-based layer, each comprising a mixture of activated carbon, carbon black, and binder, and disposed adjacent to the respective first and second conductive layers,
wherein the binder comprises polyvinylidene fluoride having a molecular weight of at least 500,000.

12. The device according to claim 11 , wherein the first conductive layer and the second conductive layer comprise conductive carbon.

13. The device according to claim 11 , wherein the device is an electrochemical double layer capacitor.

Assignees

• Corning Inc

Inventors

• Gadkaree Kishor Purushottam
• Kadam Rahul Suryakant
• Kumar Atul

Classifications

• Y02E60/13

  Energy storage using capacitors · CPC title

• Y02T10/7022

  Cross-Sectional Technologies · mapped topic

• H01G11/38 Primary

  Carbon pastes or blends; Binders or additives therein · CPC title

• H01G11/70

  characterised by their structure · CPC title

• H01G11/86

  specially adapted for electrodes (carbonisation or activation of carbon for the manufacture of electrodes H01G11/34) · CPC title