Redox flow battery for storing electrical energy in underground storage means, and use thereof

Patent metadata

Field	Value
Publication number	US-12183925-B2
Application number	US-201917297777-A
Country	US
Kind code	B2
Filing date	Nov 27, 2019
Priority date	Nov 29, 2018
Publication date	Dec 31, 2024
Grant date	Dec 31, 2024

Abstract

A redox flow battery for storing electrical energy is described, comprising a reaction cell with two electrode chambers for catholyte and anolyte, each of which is connected to at least one liquid reservoir, the electrode chambers being separated by a membrane, being equipped with electrodes, and each being filled with electrolyte solutions which contain redox-active components dissolved or dispersed in an aqueous electrolyte solvent, as well as conducting salts dissolved therein and possibly further additives. A second embodiment relates to a redox flow battery for storing electrical energy, comprising a reaction cell with an electrode chamber for an electrolyte solution, which is connected to at least one liquid reservoir, the electrode chamber being equipped with a cathode and an anode, and being filled with electrolyte solution which contains redox-active components dissolved or dispersed in an aqueous electrolyte solvent, as well as conductive salts dissolved therein and possibly further additives. The redox flow cells are characterized in that the at least one liquid reservois is an underground storage means in which temperatures of at least 30° C. prevail, in that the concentration of the salts dissolved in the electrolyte solutions is at least 10% by weight, and in that the catholyte or the electrolyte solution contains selected redox-active and temperature-stable components. In the first embodiment, the anolyte contains a water-soluble redox-active component and in the second embodiment, the anolyte or the electrolyte solution contains a zinc salt.

First claim

The invention claimed is:

1. A redox-flow-battery for storing electrical energy comprising a reaction cell with two electrode chambers for a catholyte and an anolyte, which are each connected to at least one liquid reservoir, the electrode chambers being separated by a membrane, being equipped with electrodes, and each being filled with electrolyte solutions which contain redox-active components dissolved or dispersed in an aqueous electrolyte solvent, as well as conductive salts dissolved therein and possibly further additives, characterized in that
the at least one liquid reservoir is an underground storage means in which temperatures of at least 30° C. prevail, in that
the concentration of the salts dissolved in the electrolyte solutions is at least 10% by weight, in that
the anolyte contains a water-soluble or water-dispersible redox-active component, and
that the catholyte contains at least one compound or composition selected from one of the groups b), c), or d) as redox-active component, wherein

b) is an organic compound comprising at least one redox-active residue of formula (Ia)

in combination with hydrochloric acid and/or a salt selected from the group consisting of ammonium salts with inorganic or organic anions, salts with tetrafluoroborate anions or salts of trifluoromethanesulfonic acid,
c) is an organic compound comprising at least one redox-active residue of the formula (Ib)

d) is an organic compound comprising at least one redox-active residue of the formula (Ic)

R 7 , R 8 , R 9 and R 10 represent alkyl or each of R 7 and R 8 and R 9 and R 10 together with the common carbon atom form a cycloaliphatic or heterocyclic residue,
Q is —O—, —S—, —NH—, —NR 13a , —, —NR 13a R 13b + —(An m− ) 1/m , —PR 13a — or —SiR 13a R 13b —,
R 11 is —O or —S,
R 12 is —CH 2 —, —O—, —S—, —SO—, —SO 2 ——NR 13 — or —N + R 13 R 14 — (An m− ) 1/m ,
R 13 , R 13a , R 13b and R 14 independently of one another are monovalent organic residues, and
An is an m-valent anion and m is an integer of 1-4.

2. A redox-flow-battery for storing electrical energy, comprising a reaction cell with an electrode chamber for an electrolyte solution, which is connected to at least one liquid reservoir, the electrode chamber being equipped with a cathode and an anode, the electrode chamber being filled with electrolyte solution which contains redox-active components dissolved or dispersed in an aqueous electrolyte solvent, as well as conductive salts dissolved therein and optionally further additives, characterized in that
the at least one liquid reservoir is an underground storage means in which temperatures of at least 30° C. prevail, in that
the concentration of the salts dissolved in the electrolyte solutions is at least 10% by weight, in that
anolyte contains a water-soluble or water-dispersible redox-active component, and
a catholyte contains at least one compound or composition selected from one of the groups b), c), or d) as redox-active component, wherein

b) is an organic compound comprising at least one redox-active residue of formula (Ia)

in combination with hydrochloric acid and/or a salt selected from the group consisting of ammonium salts with inorganic or organic anions, salts with tetrafluoroborate anions or salts of trifluoromethanesulfonic acid,

c) is an organic compound comprising at least one redox-active residue of the formula (Ib)

d) is an organic compound comprising at least one redox-active residue of the formula (Ic)

R 7 , R 8 , R 9 and R 10 represent alkyl or each of R 7 and R 8 and R 9 and R 10 together with the common carbon atom form a cycloaliphatic or heterocyclic residue,
Q is —O—, —S—, —NH—, —NR 13a , —, —NR 13a R 13b + —(An m− ) 1/m , —PR 13a — or
—SiR 13a R 13b —,
R 11 is —O or —S,
R 12 is —CH 2 —, —O—, —S—, —SO—, —SO 2 ——NR 13 — or —N + R 13 R 14 —(An m− ) 1/m ,
R 13 , R 13a , R 13b and R 14 independently of one another are monovalent organic residues, and
An is an m-valent anion and m is an integer of 1-4.

3. The redox-flow-battery according to claim 1 , characterized in that the electrode chambers for catholyte and anolyte are separated by a semi-permeable membrane impermeable to the redox couple in the catholyte, and the anolyte contains zinc salt as a redox-active component.

4. The redox-flow-battery according to claim 2 , characterized in that the electrode chamber for catholyte and anolyte contains no membrane, and that the anolyte contains zinc salt as a redox-active component.

5. The redox-flow-battery according to claim 3 , characterized in that this contains a zinc-solid anode with the redox pair zinc (II)/zinc(0).

6. The redox-flow-battery according to claim 1 , characterized in that the temperature in the underground storage means is 30 to 90° C.

7. The redox-flow-battery according to claim 1 , characterized in that the concentration of salts dissolved in the electrolyte solutions is from 14 wt % to the saturation limit.

8. The redox-flow-battery according to claim 1 , characterized in that the state of charge of the catholyte or of the catholyte and the anolyte is less than 90%.

9. The redox-flow-battery according to claim 1 , characterized in that An m− is selected from the group of halide ions, hydroxide ions, phosphate ions, sulfate ions, perchlorate ions, hexafluorophosphate ions or tetrafluoroborate ions.

10. The redox-flow-battery according to claim 1 , characterized in that the electrolyte solution contains a compound having at least one redox-active residue of the formulae (Ia), (Ib) or (Ic), which is covalently bonded to a polymer backbone selected from the group consisting of polymethacrylates, polyacrylates, polystyrenes, polyalkylene glycols, polyalkylene imines or polyvinyl ethers.

11. The redox-flow-battery according to claim 1 , characterized in that the electrolyte solution contains oligomers or polymers containing recurring structural units corresponding to formula (V) and optionally other structural units derived from solubility-facilitating comonomers

wherein
ME is a recurring structural unit derived from a polymerizable monomer,
BG is a bridging group,
Pip is a piperidinyl residue of formula (Ia), (Ib) or (Ic), and
r is an integer from 2 to 150.

12. The redox-flow-battery according to claim 1 , characterized in that the electrolyte solution contains a redox-active compound of formula (VIa) or (VIb)

wherein R 7 , R 8 , R 9 and R 10 have the meaning defined in claim 1 ,
q is an integer from 1 to 3,
R 15 is a monovalent organic residue, which is optionally linked via an oxygen, sulfur or
nitrogen atom with the piperidinyl residue, and
R 16 is —

Assignees

• Univ Jena Friedrich Schiller

Inventors

• Schubert Ulrich Sigmar
• Hager Martin

Classifications

• H01M8/188

  by recharging of redox couples containing fluids; Redox flow type batteries · CPC title

• H01M4/368

  Liquid depolarisers · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• Y02E60/50

  Fuel cells · CPC title

• H01M4/60 Primary

  of organic compounds · CPC title