Electrochemical storage devices comprising chelated metals

Patent metadata

Field	Value
Publication number	US-12155103-B2
Application number	US-202017440596-A
Country	US
Kind code	B2
Filing date	Mar 20, 2020
Priority date	Mar 20, 2019
Publication date	Nov 26, 2024
Grant date	Nov 26, 2024

Abstract

Metal chelates, methods of making the metal chelate, electrolyte formulations comprising metal chelates, and electrochemical devices for energy storage using or including at least one metal chelate are disclosed. The disclosure also relates to a method to provide a metal to an electrolyte in a flow battery to plate an electrode while the electrode is in the battery.

First claim

The invention claimed is:

1. A flow battery electrolyte solution, comprising:
a metal component;
a chelate component;
a buffer; and
a counter ion;
wherein the metal component is a transition metal;
wherein greater than 99 mol % of the metal component in the electrolyte solution is complexed to a chelate component to thereby form a metal chelate;
wherein the electrolyte solution comprises K[Cr(PDTA)];
wherein at least a portion of the chelate component is uncomplexed and serves as a buffer; and
wherein the electrolyte solution has a pH of between 6 and 11.

2. The flow battery electrolyte solution of claim 1 , wherein the transition metal comprises chromium.

3. The flow battery electrolyte solution of claim 1 , wherein the counter ion comprises potassium.

4. The flow battery electrolyte solution of claim 1 , wherein the chelate component comprises uncomplexed PDTA.

5. The flow battery electrolyte solution of claim 1 , wherein a solubility of the metal chelate with the counter ion in the electrolyte solution is between about 0.1 M and about 2.0 M.

6. The flow battery electrolyte solution of claim 1 , wherein the electrolyte solution is a negative electrolyte solution and further comprises an additive, the additive comprising bismuth, lead, bismuth chelate, lead chelate, or any combination thereof.

7. A flow battery comprising:
the flow battery electrolyte solution of claim 1 ;
a catholyte comprising Fe(CN) 6 ; and
a membrane comprising a cation exchange membrane.

8. A flow battery electrolyte solution, comprising:
a metal component;
a chelate component;
a buffer; and
a counter ion;
wherein at least a portion of the metal component complexes with at least a portion the chelate component to thereby form a metal chelate;
wherein the metal component is a transition metal;
wherein the chelate component comprises PDTA;
wherein the electrolyte solution comprises K[Cr(PDTA)]; and
wherein the buffer comprises K 2 B 4 O 7 , K 2 HPO 4 , Na 2 B 4 O 7 , uncomplexed BDTA, uncomplexed CyDTA, uncomplexed EDTA, uncomplexed NTA, uncomplexed PDTA, or any combination thereof.

9. The flow battery electrolyte solution of claim 8 , wherein the transition metal comprises chromium.

10. The flow battery electrolyte solution of claim 8 , wherein the counter ion comprises potassium.

11. The flow battery electrolyte solution of claim 8 , wherein a solubility of the metal chelate with the counter ion in the electrolyte solution is between about 0.1 M and about 2.0 M.

12. The flow battery electrolyte solution of claim 8 , wherein the chelate component coordinates with between about 90 mol % and about 100 mol % of the metal component.

13. The flow battery electrolyte solution of claim 8 , wherein a pH of the electrolyte solution is between about 6 and about 11.

14. The flow battery electrolyte solution of claim 8 , wherein the electrolyte solution is a negative electrolyte solution and further comprises an additive, the additive comprising bismuth, lead, bismuth chelate, lead chelate, or any combination thereof.

15. A flow battery comprising:
the flow battery electrolyte solution of claim 8 ;
a catholyte comprising Fe(CN) 6 ; and
a membrane comprising a cation exchange membrane.

16. A flow battery electrolyte solution, comprising:
a metal component;
a chelate component;
a buffer; and
a counter ion;
wherein at least a portion of the metal component complexes with at least a portion the chelate component to thereby form a metal chelate;
wherein the metal component is a transition metal;
wherein the chelate component is EDTA; and
wherein the buffer comprises uncomplexed BDTA, uncomplexed CyDTA, uncomplexed EDTA, uncomplexed NTA, uncomplexed PDTA, or any combination thereof.

17. The flow battery electrolyte solution of claim 16 , wherein the transition metal is chromium, titanium, manganese, vanadium, cerium, or iron.

18. The flow battery electrolyte solution of claim 16 , wherein the counter ion is potassium, sodium, lithium, ammonium, tetraethylammonium, tetrabutylammonium, or a tetraalkylammonium salt.

19. The flow battery electrolyte solution of claim 16 , wherein the electrolyte solution comprises Na[Cr(EDTA)].

20. The flow battery electrolyte solution of claim 16 , wherein a solubility of the metal chelate with the counter ion in the electrolyte solution is between about 0.1 M and about 2.0 M.

21. The flow battery electrolyte solution of claim 16 , wherein the chelate component coordinates with between about 90 mol % and about 100 mol % of the metal component.

22. The flow battery electrolyte solution of claim 16 , wherein a pH of the electrolyte solution is between about 6 and about 11.

23. The flow battery electrolyte solution of claim 16 , wherein the electrolyte solution is a negative electrolyte solution and further comprises an additive, the additive comprising bismuth, lead, bismuth chelate, lead chelate, or any combination thereof.

24. A flow battery comprising:
the flow battery electrolyte solution of claim 16 ;
a catholyte comprising Fe(CN) 6 ; and
a membrane comprising a cation exchange membrane.

Assignees

• Univ Colorado Regents

Inventors

• Waters Scott
• Marshak Michael
• Robb Brian Hallett

Classifications

• H01M8/188 Primary

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

• Y02E60/50

  Fuel cells · CPC title

• H01M2300/0002

  Aqueous electrolytes · CPC title

• C07C229/76

  Metal complexes of amino carboxylic acids · CPC title

• H01M8/1016 Primary

  characterised by the electrolyte material (H01M8/12 takes precedence) · CPC title