Inexpensive metal-free organic redox flow battery (ORBAT) for grid-scale storage

• US 9,614,245 B2
• Filed: 06/17/2014
• Issued: 04/04/2017
• Est. Priority Date: 06/17/2013
• Status: Active Grant

• Current Assignee: University of Southern California
• Original Assignee: University of Southern California
• Inventors: Narayan, Sri, Prakash, Surya G. K., Yang, Bo, Hoober-Burkhardt, Lena, Krishnamoorthy, Sankarganesh
• Primary Examiner(s): Stagg, Miriam
• Assistant Examiner(s): Haske, Wojciech
• Application Number:
  US14/307,030
• Publication Number:
  US 20140370403A1
• Time in Patent Office: 1,022 Days
• Field of Search: None
• CPC Class Codes: H01M 2250/10 Fuel cells in stationary systems, e.g. emergency power source in plant
• CPC Class Codes: H01M 2300/0002 Aqueous electrolytes
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 8/08 Fuel cells with aqueous electrolytes
• CPC Class Codes: H01M 8/188 by recharging of redox couples containing fluids; Redox flow type batteries
• CPC Class Codes: H01M 8/20 Indirect fuel cells, e.g. fuel cells with redox couple being irreversible H01M8/18 takes precedence
• CPC Class Codes: Y02B 90/10 Applications of fuel cells in buildings
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A flow battery includes a positive electrode, a positive electrode electrolyte, a negative electrode, a negative electrode electrolyte, and a polymer electrolyte membrane interposed between the positive electrode and the negative electrode. The positive electrode electrolyte includes water and a first redox couple. The first redox couple includes a first organic compound which includes a first moiety in conjugation with a second moiety. The first organic compound is reduced during discharge while during charging the reduction product of the first organic compound is oxidized to the first organic compound. The negative electrode electrolyte includes water and a second redox couple. The second couple includes a second organic compound including a first moiety in conjugation with a second moiety. The reduction product of the second organic compound is oxidized to the second organic compound during discharge.

Claims

1. A flow battery comprising:

a positive electrode;

a positive electrode electrolyte including water and a first redox couple, the positive electrode electrolyte flowing over and contacting the positive electrode, the first redox couple including a first organic compound, the first organic compound including a first moiety having formula 1 in conjugation with a second moiety having formula 2 and a reduction product of the first organic compound, the first organic compound being reduced during discharge;

2. The flow battery of claim 1 further comprising:

a positive electrode reservoir in fluid communication with the positive electrode, the positive electrode electrolyte being stored in the positive electrode reservoir to charge and discharge the flow battery; and

a negative electrode reservoir in fluid communication with the negative electrode, the negative electrode electrolyte being stored in the negative electrode reservoir to charge and discharge the flow battery.

3. The flow battery of claim 1 wherein:

the first organic compound is a first quinone and the reduction product of the first organic compound is a first hydroquinone.

4. The flow battery of claim 3 wherein the first quinone has a standard electrode potential greater than 0.6 volts relative to a standard hydrogen electrode.

5. The flow battery of claim 3 wherein the first quinone is described by formula 5 or 6 or salts thereof:

6. The flow battery of claim 5 wherein R₄, R₅, R₆, R₇ are each independently —

NO₂, —

N(R₂)₃⁺X<sup>−

, —

CF</sup>₃, CCl₃, —

CN, —

SO₃H, —

PO₃H₂, —

COOH, —

OH, —

O⁻

M⁺, —

SO₃⁻

M⁺, PO₃<sup>2−

M+</sup>₂, —

COO⁻

M⁺, —

COOR₂, F, Cl, Br, —

CHO, —

COR₂ where R₂ is H or C_1-10alkyl, M⁺ is a positively charged counter-ion, and X⁻

is a negatively charged-ion.

7. The flow battery of claim 5 wherein R₄, R₅, R₆, R₇ are each independently H, —

NO₂, —

CF₃, or —

SO₃H.

8. The flow battery of claim 3 wherein the first quinone includes a component selected from the group consisting of:

9. The flow battery of claim 1 wherein the positive electrode electrolyte and/or the negative electrode electrolyte includes a component selected from the group consisting of:

10. The flow battery of claim 1 wherein the second organic compound has the following formula:

11. The flow battery of claim 1 wherein the positive electrode electrolyte and/or the negative electrode electrolyte has a pH from 9 to 14.

12. The flow battery of claim 11 wherein the positive electrolyte has a pH from 9 to 14 and includes a compound selected from the group consisting of:

13. The flow battery of claim 1 wherein the positive electrode electrolyte and/or the negative electrode electrolyte further includes an additional solvent other than water.

14. The flow battery of claim 13 wherein the additional solvent is selected from the group consisting of dimethylformamide, C_1-4 alcohols, acetone nitrile, and combinations thereof.

15. The flow battery of claim 1 wherein 1, 2, 3, 4, 5, or 6 of R₁₆-R₂₃ are electron withdrawing groups selected from the group consisting of —

NO₂, —

N(R₂)₃⁺X⁻

, —

CF₃, CCl₃, —

CN, —

SO₃H, —

PO₃H₂, —

COOH, —

OH, —

O⁻

M⁺, —

SO₃⁻

M⁺, —

PO₃²⁻

M⁺₂, —

COO⁻

M⁺, —

COOR₂, F, Cl, Br, —

CHO, and —

COR₂ where R₂ is H or C_1-10 alkyl and M⁺ is a positively charged counter-ion.

16. The flow battery of claim 1 wherein 1, 2, 3, 4, 5, or 6 of R₁₆-R₂₃ are electron donating groups selected from the group consisting of C_1-10alkyl, NH₂, —

NHR₂, —

N(R₂)₂, —

O⁻

M⁺, —

NHCOR₂, —

OR₂, —

CH₃, —

C₂H₅, and phenyl where R₂ is H or C_1-10 alkyl and M⁺ is a positively charged counter-ion.

17. The flow battery of claim 1 wherein 1, 2, 3, 4, 5, or 6 of R₁₆-R₂₃ are a functional groups that increases water solubility selected from the group consisting of —

SO₃H, , —

PO₃H₂, —

COOH, —

OH, —

O⁻

M⁺, —

SO₃⁻

M⁺, —

PO₃²⁻

M⁺₂, —

COO⁻

M⁺, pyridinyl, imidazoyl, and pyrroyl, where M⁺ is a positively charged counter-ion.

18. A flow battery comprising:

a positive electrode;

a positive electrode electrolyte including water and a first quinone redox couple, the first quinone redox couple including a first quinone and a first hydroquinone, the first quinone being reduced to the first hydroquinone during discharge, the first quinone selected from the group consisting of benzoquinone and benzoquinones that are substituted with an electron withdrawing group;

a negative electrode;

a negative electrode electrolyte flowing over and contacting the negative electrode, the negative electrode electrolyte including a second organic compound having formula 8 or 9;

19. The flow battery of claim 18 wherein the electron withdrawing group is —

NO₂, —

N(R₂)₃⁺X⁻

, —

CF₃, CCl₃, —

CN, —

SO₃H, —

COOH, —

COOR, F, Cl, Br, —

CHO, or —

COR₂ where R₂ is H or C_1-10alkyl and X⁻

is a negatively charged counter-ion.

20. The flow battery of claim 18 wherein the negative electrode electrolyte includes water, the negative electrode electrolyte flowing over and contacting the negative electrode.

21. The flow battery of claim 18 wherein 1, 2, 3, 4, 5, or 6 of R₁₆-R₂₃ are electron withdrawing groups selected from the group consisting of —

NO₂, —

N(R₂)₃⁺X⁻

, —

CF₃, CCl₃, —

CN, —

SO₃H, —

PO₃H₂, —

COOH, —

OH, —

O⁻

M⁺, —

SO₃⁻

M⁺, —

PO₃²⁻

M⁺₂, —

COO ⁻

M⁺, —

COOR₂, F, Cl, Br, —

CHO, and —

COR₂ where R₂ is H or C_1-10alkyl and M⁺ is a positively charged counter-ion.

22. The flow battery of claim 18 wherein 1, 2, 3, 4, 5, or 6 of R₁₆-R₂₃ are electron donating groups selected from the group consisting of C_1-10alkyl, NH₂, —

NHR₂, —

N(R₂)₂, —

O⁻

M⁺, —

NHCOR₂, —

OR₂, —

CH₃, —

C₂H₅, and phenyl where R₂ is H or C_1-10 alkyl and M⁺is a positively charged counter-ion.

23. The flow battery of claim 18 wherein 1, 2, 3, 4, 5, or 6 of R₁₆-R₂₃ are a functional groups that increases water solubility selected from the group consisting of —

SO₃H, , —

PO₃H₂, —

COOH, —

OH, —

O⁻

M⁺, —

SO₃⁻

M⁺, —

PO₃²⁻

M⁺₂, —

COO⁻

M⁺, pyridinyl, imidazoyl, and pyrroyl, where M⁺is a positively charged counter-ion.