Auxiliary electrode mediated membrane-free redox electrochemical cell for energy storage

Patent metadata

Field	Value
Publication number	US-11411231-B2
Application number	US-202016992083-A
Country	US
Kind code	B2
Filing date	Aug 12, 2020
Priority date	Aug 15, 2019
Publication date	Aug 9, 2022
Grant date	Aug 9, 2022

Abstract

The invention provides a membrane-free redox cell utilizing auxiliary electrodes that facilitate fast charging and discharging of anolyte and catholyte for electrochemical energy storage. The anode and cathode chambers are ionically separated, and electrically connected through a conductor joining auxiliary electrodes comprised of a redox material. In use, charging/discharging of the galvanic cell takes place between primary electrodes, and the redox material is immersed in the electrolyte in both anode and cathode chambers.

First claim

The invention claimed is:

1. A galvanic cell comprising:
ionically isolated cathodic and anodic half cells, the cathodic half cell comprising a primary cathode and an auxiliary anode in a cathodic electrolyte, the anodic half cell comprising a primary anode and an auxiliary cathode in an anodic electrolyte, the cathodic electrolyte being ionically isolated from the anodic electrolyte; the primary cathode comprising a primary cathode terminal, and the primary anode comprising a primary anode terminal, the primary cathode and anode terminals being electrically connected through an external storage and discharge mechanism; and the auxiliary anode being electrically coupled to the auxiliary cathode by an electron conductor, the cathodic half cell being thereby electrically coupled to the anodic half cell through the electron conductor to form a reversible circuit with reversible half cell reactions that alternatively mediate electrochemical energy storage reactions and electrochemical energy discharge reactions.

2. The galvanic cell of claim 1 , wherein the cathodic electrolyte comprises V 3+ and V 2+ , and wherein the anodic electrolyte comprises VO 2+ and VO 2+ .

3. The galvanic cell of claim 2 , wherein to mediate electrochemical energy storage by the electrochemical energy storage reactions, VO 2+ in the anodic electrolyte is oxidized at the primary anode to form VO 2+ , and V 3+ in the cathodic electrolyte is reduced at the primary cathode to form V 2+ .

4. The galvanic cell of claim 3 , wherein to mediate electrochemical energy discharge by the electrochemical energy discharge reactions, VO 2+ in the anodic electrolyte is reduced at the primary anode to form VO 2+ , and V 2+ in the cathodic electrolyte is oxidized at the primary cathode to form V 3+ .

5. The galvanic cell of claim 4 , wherein the cathodic electrolyte and the anodic electrolyte are vanadyl sulfate solutions in an acidic supporting electrolyte.

6. The galvanic cell of claim 5 , wherein the auxiliary anode and/or auxiliary cathode comprises: a redox metal oxide or a mixed metal oxide; or, wherein the auxiliary anode comprises tin IV oxide (SnO 2 ); or, wherein the auxiliary cathode comprises tin II oxide (SnO); or, wherein the auxiliary anode and/or auxiliary cathode comprise a composite electrode comprising a carbonaceous substrate material; or, wherein the auxiliary anode and/or auxiliary cathode comprise an ionomer film coating covering the auxiliary anode and/or auxiliary cathode; or, wherein the auxiliary anode and/or auxiliary cathode comprises a redox gel material.

7. The galvanic cell of claim 6 , wherein the auxiliary anode comprises tin IV oxide (SnO 2 ), and the auxiliary cathode comprises tin II oxide (SnO), wherein to mediate electrochemical energy storage by the electrochemical energy storage reactions, a portion of the tin IV in the auxiliary anode is reduced to tin II, and a portion of the tin II in the auxiliary cathode is oxidized to tin IV.

8. The galvanic cell of claim 7 , wherein to mediate electrochemical energy discharge by the electrochemical energy discharge reactions, a portion of the tin II in the auxiliary anode is oxidized to tin IV, and a portion of the tin IV in the auxiliary cathode is reduced to tin II.

9. The galvanic cell of claim 6 wherein the ionomer film coating comprises an ion conductive material that is an electronic insulator; a perfluorosulfonic acid (PFSA) ionomer dispersion; a polyethylene oxide (PEO); or, a polypropylene oxide (PPO).

10. The galvanic cell of claim 6 , wherein the redox gel material comprises an ion conducting and electron conducting media supported on a substrate or a porous matrix; or a ferrocene (Fc) based gel; or an ionic liquid based gel; or, a redox active polymer.

11. The galvanic cell of claim 10 , wherein the redox active polymer comprises a conjugated polymer backbone.

12. The galvanic cell of claim 11 , wherein the conjugated polymer backbone comprises a poly aniline (PANI); a poly (3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) and/or wherein the conjugated polymer backbone comprises a redox active group substituent.

13. The galvanic cell of claim 12 , wherein the redox active group substituent is a quinone, imide, carbazole, or ferrocene.

14. The galvanic cell of claim 1 , wherein the cathodic electrolyte is circulated from a cathodic electrolyte storage tank through the cathodic half cell, and the anodic electrolyte is circulated from an anodic electrolyte storage tank through the anodic half cell.

15. The galvanic cell of claim 1 , wherein the cathodic and anodic electrolytes comprise a redox electrolyte pair, the auxiliary anode and auxiliary cathode comprise an auxiliary electrode pair, and the primary cathode and primary anode comprise a primary electrode pair, and:
a) the redox electrolyte pair comprises:
i) vanadyl species, or
ii) zinc (Zn) and iron (Fe) species, or
iii) anthraquinone sulfonate species (AQS) and Fe species, or
iv) benzoquinone (BQ) and Zn species, or
v) Fe and chromium (Cr) species;
the auxiliary electrode pair comprises SnO 2 and SnO; and
the primary electrode pair comprises:
i) platinum on carbon catalyst (Pt/C) coated on carbon cloth, or
ii plain carbon paper, or
iii) plain carbon cloth; or

b) the redox electrolyte pair comprises:
i) vanadyl species, or
ii) AQS and Fe species, or
iii) BQ and Zn species, or
iv) Fe and Cr species, or
v) quinone and iodine species;
the auxiliary electrode pair comprises NiOOH and Ni(OH) 2 ; and
the primary electrode pair comprises:
i) MnO 2 coated on carbon, or
ii) ii) plain carbon paper, or iii) plain carbon cloth; or,

c) the redox electrolyte pair comprises a quinone-based electrolyte comprising;
i) zinc particles; or
ii) MnO 2 particles;
the auxiliary electrode pair comprises SnO 2 and SnO; and
the primary electrode pair comprises porous carbon foam or carbon felt; or,

d) the redox electrolyte pair comprises a quinone-based electrolyte comprising zinc particles; and, the auxiliary electrode pair comprises NiOOH and Ni(OH) 2 ; and, the primary electrode pair comprises porous carbon foam or carbon felt.

16. The galvanic cell of claim 15 , wherein the redox electrolyte is circulated through porous concentrically arranged primary and auxiliary electrode pairs.

17. The galvanic cell of claim 16 , wherein the primary and auxiliary electrode pairs are separated by a chemically inert insulating mesh.

18. The galvanic cell of claim 15 , wherein the redox electrolyte pair comprises a gel-type electrolyte.

19. The galvanic cell of claim 15 , wherein the anodic electrolyte comprises a non-aqueous media housed in an anaerobic anode compartment, and the non-aqueous media comprises a mixture of quinone species.

Assignees

• Uti Lp

Inventors

• Venkatesan Senthil Velan
• Karan Kunal
• Larter Stephen
• Thangadurai Venkataraman
• Radovic Jagos R

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/9016

  Oxides, hydroxides or oxygenated metallic salts · CPC title

• H01M4/8626

  characterised by the form · CPC title

• H01M8/04194 Primary

  Concentration measuring cells · CPC title

• H01M8/188 Primary

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