High pore volume utilization carbon and electric double layer capacitor

Patent metadata

Field	Value
Publication number	US-9799459-B2
Application number	US-201514804462-A
Country	US
Kind code	B2
Filing date	Jul 21, 2015
Priority date	Aug 8, 2014
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

An electric double layer capacitor electrode, including:
an activated carbon having:
a pore volume utilization efficiency (PVUE) of from about 200 to 290 F/cm 3 , wherein PVUE is the ratio of the activated carbon gravimetric capacitance (F/g) to the pore volume (cm 3 /g) of the activated carbon; a low non-linearity value of from 0.1 to 5%; and a total pore volume of from 0.32 to 0.56 cm 3 /g.

Also disclosed is a method of making an electric double layer capacitor electrode, and a method of characterizing the performance of activated carbon, and the electrode, in an electric double layer capacitor (EDLC) device, as defined, herein.

First claim

What is claimed is:

1. An electric double layer capacitor electrode, comprising:
an activated carbon having:
a pore volume utilization efficiency (PVUE) of from 200 to 290 F/cm 3 , wherein PVUE is the quotient of the activated carbon gravimetric capacitance (F/g) over the pore volume (cm 3 /g) of the activated carbon;
a low non-linearity value of from 0.1 to 5%; and
a total pore volume of from 0.32 to 0.56 cm 3 /g.

2. The electrode of claim 1 wherein the activated carbon is a carbon dioxide activated carbon.

3. The electrode of claim 1 wherein the electrode has at least one high capacitive cell having a gravimetric capacitance of from 90 to 30F/g, which cell is free of cation trapping, free of increased ionic resistance, or both.

4. The electrode of claim 1 wherein the activated carbon has a gravimetric capacitance of from 50 to 130F/g.

5. The electrode of claim 1 wherein the activated carbon has a gravimetric capacitance of 90 to 130F/g, a pore volume of 0.35 to 0.45 cm 3 /g, and a pore volume utilization efficiency of 230 to 270 F/cc.

6. The electrode of claim 1 wherein the activated carbon has a pore volume of 0.25 to 0.4 cm 3 /g in pores having a diameter of from 0.01 to 1 nm.

7. The electrode of claim 1 wherein the electrode in a large cell format having a TEMA-TFB electrolyte, the cell has an ESR of 0.35 to 7 milliohms.

8. The electrode of claim 1 wherein the electrode in a large cell format having a TEMA-TFB electrolyte, and in a 3.0 V stress test, has a capacitance degradation at 50 hrs of from 6 to 7%.

9. A method of making an electric double layer capacitor, comprising:
an activated carbon having:
a pore volume utilization efficiency (PVUE) of from 200 to 290 F/cm 3 , wherein PVUE is the quotient of the activated carbon gravimetric capacitance (F/g) over the pore volume (cm 3 /g) of the activated carbon;
a low non-linearity value of from 0.1 to 5%; and

a total pore volume of from 0.32 to 0.56 cm 3 /g the method comprising:
activating a carbon by heating a char in a furnace at from 700 to 1,000° C. for from 2 to 6 hrs, at from 0.5 to 5 rpm, and the furnace having a CO 2 volumetric flow rate of about 10 to 20 liter per minute per kg of furnace load, to form a carbon dioxide activated carbon; and
forming an electrode with the carbon dioxide activated carbon.

10. The method of claim 9 wherein the activated carbon has a gravimetric capacitance of from 50 to 130 F/g, a pore volume of from 0.32 to 0.56 cm 3 /g, and a pore volume utilization efficiency of from 200 to 290 F/cc.

11. The method of claim 9 wherein the activated carbon has pore volume of from 0.25 to 0.4 cm 3 /g in pores having a diameter from 0.01 to 1 nm.

Assignees

• Corning Inc

Inventors

• Gadkaree Kishor Purushottam
• Kumar Atul

Classifications

• H01G11/24 Primary

  characterised by structural features of the materials making up or comprised in the electrodes, e.g. form, surface area or porosity; characterised by the structural features of powders or particles used therefor · CPC title

• H01G11/86

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

• Y02E60/13

  Energy storage using capacitors · CPC title

• H01G11/34

  characterised by carbonisation or activation of carbon · CPC title

• C01B32/336

  characterised by gaseous activating agents · CPC title