Carbon surface modification for three-volt ultracapacitor

• US 10,763,051 B2
• Filed: 03/29/2019
• Issued: 09/01/2020
• Est. Priority Date: 10/08/2012
• Status: Active Grant

• Current Assignee: UCAP Power, Inc.
• Original Assignee: Maxwell Technologies Incorporated (Tesla Inc.)
• Inventors: Bendale, Priya, Crawford, Robert, Mitchell, Porter, Nelson, Jeffrey, Schafer, Doug, Xi, Xiaomei
• Primary Examiner(s): Thomas, Eric W
• Assistant Examiner(s): Ramaswamy, Arun
• Application Number:
  US16/370,172
• Publication Number:
  US 20190362908A1
• Time in Patent Office: 522 Days
• Field of Search: 361502, 361508, 361516, 361503, 361504, 361505
• CPC Class Codes: H01G 11/14 Arrangements or processes for adjusting or protecting hybrid or EDL capacitors emergency protective circuit arrangements specially adapted for capacitors, and effecting automatic switching in the event of an undesired change from normal working conditions H02H7/16; emergency protective circuit arrangements for limiting excess current or voltages without disconnection H02H9/00
• CPC Class Codes: H01G 11/24 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 Class Codes: H01G 11/28 arranged or disposed on a current collector; Layers or phases between electrodes and current collectors, e.g. adhesives
• CPC Class Codes: H01G 11/32 Carbon-based
• CPC Class Codes: H01G 11/34 characterised by carbonisation or activation of carbon
• CPC Class Codes: H01G 11/38 Carbon pastes or blends; Binders or additives therein
• CPC Class Codes: H01G 11/52 Separators
• CPC Class Codes: H01G 11/54 Electrolytes
• CPC Class Codes: H01G 11/58 Liquid electrolytes
• CPC Class Codes: H01G 11/60 characterised by the solvent
• CPC Class Codes: H01G 11/62 characterised by the solute, e.g. salts, anions or cations therein
• CPC Class Codes: H01G 11/68 characterised by their material
• CPC Class Codes: H01G 11/78 Cases; Housings; Encapsulations; Mountings
• CPC Class Codes: H01G 11/82 Fixing or assembling a capacitive element in a housing, e.g. mounting electrodes, current collectors or terminals in containers or encapsulations
• CPC Class Codes: H01G 11/84 Processes for the manufacture of hybrid or EDL capacitors, or components thereof
• CPC Class Codes: H01G 11/86 specially adapted for electrodes carbonisation or activation of carbon for the manufacture of electrodes H01G11/34
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

An electric double-layer ultracapacitor configured to maintain desired operation at an operating voltage of three volts, where the capacitor includes a housing component, a first and a second current collector, a positive and a negative electrode electrically coupled to one of the first and second current collectors, and a separator positioned between the positive and the negative electrode. At least one of the positive electrode and the negative electrode can include a treated carbon material, where the treated carbon material includes a reduction in a number of hydrogen-containing functional groups, nitrogen-containing functional groups and/or oxygen-containing functional groups.

Claims

1. A method of making an ultracapacitor, comprising:

providing a first current collector electrically coupled to a positive electrode and a second current collector electrically coupled to a negative electrode, and separated by a separator into a housing; and

adding an electrolyte to the housing, wherein the electrolyte comprises a quaternary ammonium salt in ionic contact with the positive electrode and the negative electrode, wherein the electrolyte comprises less than 1 M salt;

wherein the capacitor is configured to operate at 65°

C. with a cycle life of greater than 500 k cycles.

2. The method of claim 1, wherein the quaternary ammonium salt comprises a cation selected from the group consisting of Spiro-(1,1′

)-bipyrrolidinium, triethyimethyl ammonium and tetraethyl ammonium.

3. The method of claim 1, wherein the quaternary ammonium salt comprises an anion selected from the group consisting of tetrafluoroborate and iodide.

4. The method of claim 1, wherein the electrolyte further comprises acetonitrile.

5. The method of claim 1, wherein the salt concentration of the electrolyte is about 0.8 M.

6. The method of claim 1, wherein the capacitor is configured to operate at 3 volts or greater at 65°

C. and maintaining greater than 80% of its initial capacitance for over 1500 hours.

7. The method of claim 1, wherein the capacitor is configured to operate at 3 volts or greater at 65°

C. and maintaining less than 200% of its initial equivalent series resistance for over 1500 hours.

8. The method of claim 1, wherein the positive electrode and negative electrode each independently comprise a dry electrode film comprising carbon and binder.

9. A method of making an ultracapacitor, comprising:

providing a first current collector electrically coupled to a positive electrode and a second current collector electrically coupled to a negative electrode, and separated by a separator into a housing; and

adding an electrolyte to the housing, wherein the electrolyte comprises a quaternary ammonium salt in ionic contact with the positive electrode and the negative electrode, wherein the electrolyte comprises less than 1 M salt;

wherein the capacitor is configured to operate at 3 volts or greater at 65°

C. and maintaining greater than 80% of its initial capacitance for over 1500 hours.

10. The method of claim 9, wherein the quaternary ammonium salt comprises a cation selected from the group consisting of spiro-(1,1′

)-bipyrrolidinium, triethylmethyl ammonium and tetraethyl ammonium.

11. The method of claim 9, wherein the quaternary ammonium salt comprises an anion selected from the group consisting of tetrafluoroborate and iodide.

12. The method of claim 9, wherein the electrolyte further comprises acetonitrile.

13. The method of claim 9, wherein the salt concentration of the electrolyte is about 0.8 M.

14. The method of claim 9, wherein the capacitor is configured to operate at 3 volts or greater at 65°

C. and maintaining less than 200% of its initial equivalent series resistance for over 1500 hours.

15. A method of making an ultracapacitor, comprising:

providing a first current collector electrically coupled to a positive electrode and a second current collector electrically coupled to a negative electrode, and separated by a separator into a housing; and

adding an electrolyte to the housing, wherein the electrolyte comprises a quaternary ammonium salt in ionic contact with the positive electrode and the negative electrode, wherein the electrolyte comprises less than 1 M salt;

wherein the capacitor is configured to operate at 3 volts or greater at 65°

C. and maintaining less than 200% of its initial equivalent series resistance for over 1500 hours.

16. The method of claim 15, wherein the quaternary ammonium salt comprises a cation selected from the group consisting of spiro-(1,1′

)-bipyrrolidinium, triethylmethyl ammonium and tetraethyl ammonium.

17. The method of claim 15, wherein the quaternary ammonium salt comprises an anion selected from the group consisting of tetrafluoroborate and iodide.

18. The method of claim 15, wherein the electrolyte further comprises acetonitrile.

19. The method of claim 15, wherein the salt concentration of the electrolyte is about 0.8 M.