High-capacity slurry electrode and flow energy storage system based on same

Patent metadata

Field	Value
Publication number	US-2016093449-A1
Application number	US-201514871506-A
Country	US
Kind code	A1
Filing date	Sep 30, 2015
Priority date	Sep 30, 2014
Publication date	Mar 31, 2016
Grant date	—

Abstract

Disclosed herein is a high-capacity slurry electrode for use in a flow energy storage system, comprising: an electrolyte; electrode active particles, distributed in the electrolyte, functioning as an electrode active material in an electrochemical flow capacitor storage system; and a redox active material, dissolved in the electrolyte, behaving as a pseudo-capacitor through a redox reaction on a surface of the electrode active material, wherein the high-capacity slurry electrode exhibits both capacitor properties based on the electrode active particles and pseudo-capacitor properties based on the redox active material.

First claim

What is claimed is:

1 . A high-capacity slurry electrode for use in a flow energy storage system, comprising:
an electrolyte; electrode active particles, distributed in the electrolyte, functioning as an electrode active material in an electrochemical flow capacitor storage system; and a redox active material, dissolved in the electrolyte, behaving as a pseudo-capacitor through a redox reaction on a surface of the electrode active material, wherein the high-capacity slurry electrode exhibits both capacitor properties based on the electrode active particles and pseudo-capacitor properties based on the redox active material.

2 . The high-capacity slurry electrode of claim 1 , wherein the electrode active particles are made of a material selected from among active carbon, graphene, a carbon nanotube, a conductive polymer, a metal oxide, and a combination thereof.

3 . The high-capacity slurry electrode of claim 2 , wherein the electrode active particles are spherical or symmetric with a specific surface area of 1000˜4000 m 2 /g.

4 . The high-capacity slurry electrode of claim 3 , wherein the electrode active particles have a particle size of 500 nm˜500 μm.

5 . The high-capacity slurry electrode of claim 1 , wherein the redox active material is a reduced form, an oxidized form, or a derived form of an electrochemically active organic molecule based on a benzene compound having either or both of an alcohol and an amine group.

6 . The high-capacity slurry electrode of claim 1 , wherein the redox active material is a reduced form, an oxidized form, or a derived form of an electrochemically active organic molecule based on a naphthalene or anthracene compound having either or both of an alcohol and an amine group.

7 . The high-capacity slurry electrode of claim 1 , wherein the redox active material is an electrochemically active inorganic molecule selected from among KI and KBr.

8 . The high-capacity slurry electrode of claim 1 , wherein the redox active material is dissolved at a concentration of 10 −9 M˜10 M in the electrolyte.

9 . The high-capacity slurry electrode of claim 1 , wherein the redox active material is 1,4-benzenediol or benzoquinone and is dissolved at a concentration of 10 −9 M˜5 M in the electrolyte.

10 . The high-capacity slurry electrode of claim 1 , wherein the redox active material is 1,4-naphthoquinone and is dissolved at a concentration of 10 −9 M˜5 M in the electrolyte.

11 . The high-capacity slurry electrode of claim 1 , further comprising conductive agent particles dispersed in the electrolyte, the conductive agent particles being used in an amount of 50 wt % or less of the electrode active particles.

12 . The high-capacity slurry electrode of claim 1 , wherein the conductive agent is carbon black.

13 . A method for preparing the high-capacity slurry electrode of claim 1 , comprising:
dissolving a redox active material in an electrolyte to give a redox active electrolyte, the redox active material being electrochemically active so as to perform a redox reaction; and mixing electrode active particles with the redox active electrolyte, the electrode active particles functioning as an active material in an electrochemical flow capacitor storage system.

14 . The method of claim 13 , wherein the electrolyte is an aqueous electrolyte containing at least one selected from among sulfuric acid (H 2 SO 4 ), sodium sulfate (Na 2 SO 4 ), potassium chloride (KCl), potassium hydroxide (KOH), and sodium hydroxide (NaOH).

15 . The method of claim 13 , wherein the electrolyte is a mixture of an organic solvent selected from the group consisting of acetonitrile (ACN), propylene carbonate (PC), ethylene carbonate (EC), diethylene carbonate (DEC), dimethylene carbonate (DMC), and a combination thereof, and a salt selected from among an ammonium salt, a lithium salt, and a combination thereof.

16 . The method of claim 13 , wherein the electrode active particles are blended with the conducting agent particles to give a mixture powder, and the mixture powder is mixed at a weight ratio of 1:1˜1:20 with the redox active electrolyte.

17 . A high-capacity slurry electrode-based flow energy storage system, comprising:
an anode current collector and a cathode current collector, separated from each other; an ion permeable separation membrane disposed between the anode current collector and the cathode current collector; a fluid anode positioned at an electrode region between the anode current collector and the ion permeable separation membrane; and a fluid cathode positioned at an electrode region between the cathode current collector and the ion permeable separation membrane, wherein at least one of the anode and the cathode is the high-capacity slurry electrode of claim 1 , exhibiting both a capacitor property based on the electrode active particles contained in the high-capacity slurry electrode and a pseudocapacitor property based on the redox active material contained in the high-capacity slurry electrode.

18 . The high-capacity slurry electrode-based flow energy storage system of claim 17 , further comprising:
storage tanks for storing the fluid anode and the fluid cathode, respectively; a path through which the fluid anode and the fluid cathode are circulated between the respective storage tanks and the electrode region; and a pump for driving the circulation.

19 . The high-capacity slurry electrode-based flow energy storage system of claim 17 , further comprising a gasket, positioned between the anode current collector or the cathode current collector and the ion permeable separation membrane, for forming the electrode region.

20 . The high-capacity slurry electrode-based flow energy storage system of claim 19 , wherein the gasket is made of a material selected from among silicon rubber, fluororubber, butyl rubber, Teflon, neoprene, latex, chlorosulfonated polyethylene rubber, ethylene propylene rubber, styrenebutadiene rubber, butadiene rubber, and nitrile butadiene rubber.

Assignees

• Korea Energy Research Inst

Inventors

• Yoon Hana
• Yoo Jung Joon

Classifications

• H01G11/02

  using combined reduction-oxidation reactions, e.g. redox arrangement or solion · CPC title

• H01G11/58

  Liquid electrolytes · CPC title

• H01G11/32

  Carbon-based · CPC title

• Y02E60/13

  Energy storage using capacitors · CPC title

• H01G11/34

  characterised by carbonisation or activation of carbon · CPC title