Ultracapacitor with a low leakage current

Patent metadata

Field	Value
Publication number	US-11170944-B2
Application number	US-201816132849-A
Country	US
Kind code	B2
Filing date	Sep 17, 2018
Priority date	Sep 18, 2017
Publication date	Nov 9, 2021
Grant date	Nov 9, 2021

Abstract

An ultracapacitor that contains at least one electrochemical cell is provided. The cell includes a first electrode that contains a first carbonaceous coating (e.g., activated carbon particles) electrically coupled to a first current collector, a second electrode that contains a second carbonaceous coating (e.g., activated carbon particles) electrically coupled to a second current collector, an aqueous electrolyte in ionic contact with the first electrode and the second electrode and that contains a polyprotic acid (e.g., sulfuric acid), and a separator that is positioned between the first and second electrodes. Through selective control over the particular nature of the materials used to form the ultracapacitor, as well as the manner in which they are formed, a variety of beneficial properties may be achieved.

First claim

What is claimed is:

1. An ultracapacitor comprising an electrochemical cell that contains a first electrode, a second electrode, a separator positioned between the first and second electrodes, and an aqueous electrolyte that is ionic contact with the first and second electrodes,
wherein the first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating,
wherein the separator contains a crosslinked polymer film formed from a vinyl alcohol polymer, a polyethylene oxide, a polyethyleneimine, a polyethylene glycol, a cellulose acetate, a polyvinylmethylethyl ether, or a phenol formaldehyde resin, and
further wherein after being subjected to an applied voltage for 180 minutes, the ultracapacitor exhibits a leakage current of only about 1 microamp or less and wherein the ratio of the thickness of the crosslinked polymer film to the thickness of the electrochemical cell is from about 0.05 to about 1.

2. The ultracapacitor of claim 1 , wherein the first and second current collectors contain a conductive metal.

3. The ultracapacitor of claim 2 , wherein the conductive metal is aluminum or an alloy thereof.

4. The ultracapacitor of claim 1 , wherein the first carbonaceous coating, the second carbonaceous coating, or both contain activated carbon particles.

5. The ultracapacitor of claim 4 , wherein at least 50% by volume of the activated carbon particles have a size of from about 0.01 to about 30 micrometers.

6. The ultracapacitor of claim 4 , wherein the activated carbon particles have a BET surface area of from about 900 m 2 /g to about 3,000 m 2 /g.

7. The ultracapacitor of claim 6 , wherein the activated carbon particles contain a plurality of pores, wherein the amount of pores having a size of about 2 nanometers or less is about 50 vol. % or less of the total pore volume, the amount of pores having a size of from about 2 nanometers to about 50 nanometers is about 20 vol. % to about 80 vol. % of the total pore volume, and the amount of pores having a size of about 50 nanometers or more is from about 1 vol. % to about 50 vol. % of the total pore volume.

8. The ultracapacitor of claim 1 , wherein the aqueous electrolyte includes a polyprotic acid.

9. The ultracapacitor of claim 8 , wherein the polyprotic acid is sulfuric acid.

10. The ultracapacitor of claim 1 , wherein the crosslinked polymer film is formed from a vinyl alcohol polymer.

11. The ultracapacitor of claim 1 , wherein the film contains a heteropolyacid compound having the following general formula:
A m [X x Y y O z ]· n H 2 O

X and Y are independently boron, aluminum, gallium, silicon, germanium, tin, phosphorus, arsenic, antimony, bismuth, selenium, tellurium, iodine, scandium, yttrium, lanthanum, actinium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, or tungsten;
A is hydrogen or a cation;
m is an integer of from 1 to 10;
x is an integer of from 1 to 10;
y is an integer of from 2 to 20;
z is an integer of from 10 to 100; and
n is an integer of from 0 to 150.

12. The ultracapacitor of claim 11 , wherein the heteropolyacid compound is dodecamolybdophosphoric acid, ammonium molybdophosphate, sodium molybdophosphate, potassium molybdophosphate, lithium molybdophosphate, calcium molybdophosphate, magnesium molybdophosphate, dodecatungstophosphoric acid, ammonium tungstophosphate, sodium tungstophosphate, potassium tungstophosphate, lithium tungstophosphate, calcium tungstophosphate, magnesium tungstophosphate, dodecamolybdosilicic acid, ammonium molybdosilicate, sodium molybdosilicate, potassium molybdosilicate, lithium molybdosilicate, calcium molybdosilicate, magnesium molybdosilicate, dodecamolybdogermanic acid, ammonium molybdogermanate, sodium molybdogermanate, potassium molybdogermanate, lithium molybdogermanate, calcium molybdogermanate, magnesium molybdogermanate, hexamolybdotelluric acid, ammonium molybdotellurate, sodium molybdotellurate, potassium molybdotellurate, lithium molybdotellurate, calcium molybdotellurate, magnesium molybdotellurate, dodecatungstosilicic acid, ammonium tungstosilicate, sodium tungstosilicate, potassium tungstosilicate, lithium tungstosilicate, calcium tungstosilicate, magnesium tungstosilicate, or a combination thereof.

13. The ultracapacitor of claim 1 , further comprising a housing within which the first electrode, the second electrode, the separator, and the electrolyte are retained.

14. The ultracapacitor of claim 1 , wherein the separator contains a crosslinked polymer film formed from a polyethylene oxide, a polyethyleneimine, a polyethylene glycol, a cellulose acetate, a polyvinylmethylethyl ether, or a phenol formaldehyde resin.

15. The ultracapacitor of claim 1 , wherein the separator contains a crosslinked polymer film formed from a polyethyleneimine, a cellulose acetate, a polyvinylmethylethyl ether, or a phenol formaldehyde resin.

16. An ultracapacitor comprising an electrochemical cell that contains a first electrode, a second electrode, a separator positioned between the first and second electrodes, and an aqueous electrolyte that is ionic contact with the first and second electrodes,
wherein the first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating,
wherein the separator contains a crosslinked polymer film formed from a vinyl alcohol polymer, a polyethylene oxide, a polyethyleneimine, a polyethylene glycol, a cellulose acetate, a polyvinylmethylethyl ether, or a phenol formaldehyde resin and wherein the crosslinked polymer film has a thickness of from about 500 micrometers to about 10,000 micrometers.

17. The ultracapacitor of claim 16 , wherein after being subjected to an applied voltage for 180 minutes, the ultracapacitor exhibits a leakage current of only about 1 microamp or less.

18. An ultracapacitor comprising an electrochemical cell that contains a first electrode, a second electrode, a separator positioned between the first and second electrodes, and an aqueous electrolyte that is ionic contact with the first and second electrodes,
wherein the first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating,
wherein the separator contains a crosslinked polymer film that contains a heteropolyacid compound having the following general formula:
A m [X x Y y O z ]· n H 2 O

X and Y are independently boron, aluminum, gallium, silicon, germanium, tin, phosphorus, arsenic, antimony, bismuth, selenium, tellurium, iodine, scandium, yttrium, lanthanum, actinium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, or tungsten;
A is hydrogen or a cation;
m is an integer of from 1 to 10;
x is an integer of from 1 to 10;
y is an integer of from 2 to 20;
z is an integer of from 10 to 100; and
n is an integer of from 0 to 150.

Assignees

• Avx Corp
• Kyocera Avx Components Corp

Inventors

• Knopsnyder Jonathan Robert
• Hansen Shawn

Classifications

• H01G11/68

  characterised by their material · CPC title

• H01G11/42 Primary

  Powders or particles, e.g. composition thereof · CPC title

• Y02E60/13

  Energy storage using capacitors · CPC title

• H01G11/52

  Separators · CPC title

• H01G11/78

  Cases; Housings; Encapsulations; Mountings · CPC title