Supercapacitor and a method of manufacturing such a supercapacitor

• US 20030064565A1
• Filed: 09/23/2002
• Published: 04/03/2003
• Est. Priority Date: 11/09/2000
• Status: Active Grant

• Current Assignee: FOC Frankenburg Oil Company
• Original Assignee: Ultratech Incorporated (Veeco Instruments Incorporated)
• Inventors: Cederstrom, Jan, Wallace, Clarence L., Efimovitj, Alexander Kravchik, Zheng, Jie, Arulepp, Mati, Leis, Jaan, Maletin, Yurii, Perkson, Anti, Kozachkov, Sergey, Mironova, Antonina, Danilin, Valerii, Strizhakova, Natalie, Podmogilny, Sergey, Konstantinovich, Sergey Gordeev, Vasilevitj, Vasilii Sokolov, Aleksandrovna, Julia Kukushkina, Kolotilova, Julia, Izotov, Volodymyz
• Granted Patent: US 6,697,249 B2
• Time in Patent Office: Days
• US Class Current: 438/398
• 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 11/34 characterised by carbonisation or activation of carbon
• 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: H01M 4/583 Carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/623 fluorinated polymers
• CPC Class Codes: H01M 50/44 Fibrous material
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

An electric double layer capacitor including at least one pair of polarizable electrodes connected to current collectors, a separator made of ion-permeable but electron-insulating material interposed between the electrodes in each pair of electrodes, and a liquid electrolyte. According to the invention the electrodes include a layer of carbon particles having a narrow distribution of nanopores therein, the pore sizes of the nanopores being adapted to fit the ion sizes of the electrolyte. The invention also relates to a method of manufacturing such a supercapacitor.

Claims

1. An electric double layer capacitor including at least one pair of polarizable electrodes connected to current collectors, a separator made of ion-permeable but electron-insulating material interposed between the electrodes in each pair of electrodes, and a liquid electrolyte, characterised in that the electrodes include a layer of carbon particles having a narrow distribution of nanopores therein, the pore sizes of the nanopores being adapted to fit the ion sizes of the electrolyte.

2. The capacitor according to claim 1, characterised in that the layer of carbon particles in each electrode includes 2-10% wt of a binder.

3. The capacitor according to claim 2, characterised in that the binder is a fluorine-containing polymer.

4. The capacitor according to claim 3, characterised in that the layer of carbon particles in each electrode includes 1-15 wt % of thermo-expanded graphite (TEG) for improving the transport of ions in the layer.

5. The capacitor according to claim 3, characterised in that the layer of carbon particles in each electrode includes 1-15 wt. % of collodial carbon for improving the transport of ions in the layer.

6. The capacitor according to claim 1, characterised in that the layer of carbon particles in each electrode includes 0.5-10 wt. % of SiO₂ for increasing capacitance.

7. The capacitor according to claim 1, characterised in that the thickness of the electrodes lies within the range of 5-150 microns.

8. The capacitor according to claim 7, characterised in that the size of the carbon particles in the electrodes is less than about 10 microns.

9. The capacitor according to claim 1, characterised in that the carbon particles in the electrodes are produced by halogenation of particles of inorganic carbon containing compounds.

10. The capacitor according to claim 9, characterised in that the carbon particles in the electrodes are produced by halogenation of particles of inorganic carbon containing compounds based on metals, metalloids or combinations thereof from the group of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Cr, Fe, Al, Si, B and Ca.

11. The capacitor according to claim 9, characterised in that the nanopores in the electrodes of each pair of electrodes have different sizes in order to match different sizes of anions and cations in the electrolyte.

12. The capacitor according to claim 11, characterised in that the electrodes in each pair of electrodes have the same capacitance.

13. The capacitor according to claim 12, characterised in that the electrodes in each pair of electrodes have different volume.

14. The capacitor according to claim 13, characterised in that the positively and negatively charged electrode in each pair of electrodes are balanced according to zero-charged potential.

15. The capacitor according to claim 11, characterised in that a layer of aluminium having a thickness of 2-5 microns is deposited on the side of the electrode which is attached to a current collector.

16. The capacitor according to claim 1, characterised in that the separator is a porous dielectric film or paper, such as anonwoven polypropylene, a polyethylene separator film, a polyethylene terephthalate nuclear membrane or a cellulose separator paper, the separator thickness being about 5-100 microns, preferably 5-30 microns

17. The capacitor according to claim 1, characterised in that the separator is a thin film of a dielectric material deposited on each electrode on the side opposite to the side to which the current collector is attached.

18. The capacitor according to claims 1, characterised in that the liquid electrolyte is a water based electrolyte or an organic electrolyte.

19. The capacitor according to claim 18, characterised in that the liquid electrolyte comprises at least one salt selected from the group of tetrafluorborates or hexafluorophosphates of tetraalkylammonium, tetrakis(dialkylamino) phosphonium, N,N-dialkyl- 1,4-diazabicyclo[2.2.2]octanediium or their mixture, dissolved in an aprotic polar solvent or a mixture of such solvents selected from the group of acetonitrile, propionitrile, benzonitrile, butyronitrile, 3-methoxypropionitrile, gamma-butyrolactone, -valerolactone, ethylene carbonate, propylene carbonate, N,N-dimethylformamide, 1-methyl-2-pyrrolidinone, dimethoxyethane, methyl ethyl ketone and tetrahydrofuran;

the concentration of salts being 0.5-3.0 mol/l.

20. An electrolyte for an electric double layer capacitor, characterised in that a voltage levelling agent, chosen from the groups of twinned aromatic hydrocarbons(including heterosubstituted ones), aromatic nitriles, quinones and nitro- or amino-derivatives or combinations of nitronitriles (nitro-cyano derivatives) or cyanosustituted quinones is comprised in the electrolyte.

21. Use of magnetic pulse joining for attaching a foil or mesh of conductive material to a sheet of carbonaceous electrode.