Extending the lifetime of organic flow batteries via redox state management

Patent metadata

Field	Value
Publication number	US-2021391591-A1
Application number	US-201917281767-A
Country	US
Kind code	A1
Filing date	Oct 1, 2019
Priority date	Oct 1, 2018
Publication date	Dec 16, 2021
Grant date	—

Abstract

The invention provides flow batteries including an anthraquinone and methods of discharging the batteries that reduce loss of capacity. The loss of capacity of anthraquinones may be mitigated by controlling the state of charge and/or oxidizing the negolyte.

First claim

What is claimed is:

1 . A method of discharging a battery comprising the steps of:
a) providing a flow battery comprising a negolyte comprising an anthrahydroquinone in aqueous solution or suspension in contact with a first electrode, a posolyte comprising a redox active species in contact with a second electrode, and a barrier separating the negolyte and posolyte; and b) discharging the flow battery so that that anthrahydroquinone is oxidized to an anthraquinone and the redox active species is reduced, wherein the state of charge of the anthrahydroquinone at the end of charging is less than 100%.

2 . The method of claim 1 , further comprising providing an oxidizing agent to the discharged negolyte.

3 . A method of discharging a battery comprising the steps of:
a) providing a flow battery comprising a negolyte comprising an anthrahydroquinone in aqueous solution or suspension in contact with a first electrode, a posolyte comprising a redox active species in contact with a second electrode, and a barrier separating the negolyte and posolyte; b) discharging the flow battery so that that anthrahydroquinone is oxidized to an anthraquinone and the redox active species is reduced; and c) providing an oxidizing agent to the discharged negolyte.

4 . The method of any one of claims 1 - 3 , wherein the anthraquinone is of formula (I):

wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 is independently selected from H; halo; optionally substituted C 1-6 alkyl; oxo; optionally substituted C 3-10 carbocyclyl; optionally substituted C 1-9 heterocyclyl having one to four heteroatoms independently selected from O, N, and S; optionally substituted C 6-20 aryl; optionally substituted C 1-9 heteroaryl having one to four heteroatoms independently selected from O, N, and S; —CN; —NO 2 ; —OR a ; —SR a ; —N(R a ) 2 ; —C(═O)R a ; —C(═O)OR a ; —S(═O) 2 R a ; —S(═O) 2 OR a (e.g., SO 3 H); —P(═O)R a2 ; and —P(═O)(OR a ) 2 ; or any two adjacent groups selected from R 1 , R 2 , R 3 , and R 4 are joined to form an optionally substituted 3-6 membered ring, or an ion thereof, wherein each R a is independently H; C 1-6 alkyl; optionally substituted C 3-10 carbocyclyl; optionally substituted C 1-9 heterocyclyl having one to four heteroatoms independently selected from O, N, and S; optionally substituted C 6-20 aryl; optionally substituted C 1-9 heteroaryl having one to four heteroatoms independently selected from O, N, and S; an oxygen protecting group; or a nitrogen protecting group.

5 . The method of any one of claims 1 - 4 , wherein the redox active species comprises bromine, chlorine, iodine, molecular oxygen, vanadium, chromium, cobalt, iron, aluminum, manganese, cobalt, nickel, copper, or lead.

6 . The method of claim 1 or 2 , wherein the state of charge at the end of charging is between 45-95%.

7 . The method of claim 2 or 3 , wherein the oxidizing agent is molecular oxygen.

8 . The method of claim 7 , wherein the molecular oxygen is provided in gaseous form.

9 . The method of claim 8 , wherein the gaseous form is air.

10 . The method of claim 1 , wherein the battery is cycled for at least 100 times.

11 . The method of claim 2 or 3 , wherein the oxidizing agent is provided after each discharge.

12 . The method of claim 2 or 3 , wherein the oxidizing agent is not provided until after at least 10 cycles.

13 . A flow battery comprising:
i) a negolyte comprising an anthrahydroquinone in aqueous solution or suspension in contact with a first electrode; ii) a posolyte comprising a redox active species in contact with a second electrode; iii) a barrier separating the negolyte and posolyte; and iv) a controller to limit the state of charge of the anthrahydroquinone to less than 95%.

14 . The flow battery of claim 13 , further comprising a source of oxidizing agent in fluid communication with the negolyte and/or a gas dispersion element in the negolyte.

15 . A flow battery comprising:
i) a negolyte comprising an anthrahydroquinone in aqueous solution or suspension in contact with a first electrode; ii) a posolyte comprising a redox active species in contact with a second electrode; iii) a barrier separating the negolyte and posolyte; and iv) a source of oxidizing agent in fluid communication with the negolyte and/or a gas dispersion element in the negolyte.

16 . The flow battery of any one of claims 13 - 15 , wherein the anthraquinone is of formula (I):

wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 is independently selected from H; halo; optionally substituted C 1-6 alkyl; oxo; optionally substituted C 3-10 carbocyclyl; optionally substituted C 1-9 heterocyclyl having one to four heteroatoms independently selected from O, N, and S; optionally substituted C 6-20 aryl; optionally substituted C 1-9 heteroaryl having one to four heteroatoms independently selected from O, N, and S; —CN; —NO 2 ; —OR a ; —SR a ; —N(R a ) 2 ; —C(═O)R a ; —C(═O)OR a ; —S(═O) 2 R a ; —S(═O) 2 OR a (e.g., SO 3 H); —P(═O)R a2 ; and —P(═O)(OR a ) 2 ; or any two adjacent groups selected from R 1 , R 2 , R 3 , and R 4 are joined to form an optionally substituted 3-6 membered ring, or an ion thereof, wherein each R a is independently H; C 1-6 alkyl; optionally substituted C 3-10 carbocyclyl; optionally substituted C 1-9 heterocyclyl having one to four heteroatoms independently selected from O, N, and S; optionally substituted C 6-20 aryl; optionally substituted C 1-9 heteroaryl having one to four heteroatoms independently selected from O, N, and S; an oxygen protecting group; or a nitrogen protecting group.

17 . The flow battery of any one of claims 13 - 16 , wherein the redox active species comprises bromine, chlorine, iodine, molecular oxygen, vanadium, chromium, cobalt, iron, aluminum, manganese, cobalt, nickel, copper, or lead.

18 . The flow battery of claim 13 or 14 , wherein the state of charge is between 45-95%.

19 . The flow battery of claim 14 or 15 , wherein the oxidizing agent is molecular oxygen.

20 . The flow battery of claim 19 , wherein the molecular oxygen is provided in gaseous form.

21 . The flow battery of claim 20 , wherein the gaseous form is air.

22 . A method of reducing loss of capacity in a flow battery comprising the steps of:
a) providing a flow battery comprising a negolyte in aqueous solution or suspension in contact with a first electrode, a posolyte in contact with a second electrode, and a barrier separating the negolyte and posolyte; and b) charging the negolyte to less than 100% before discharge or oxidizing the negolyte after discharge.

23 . The method of claim 22 , wherein the negolyte comprises an organic redox active compound or an organometallic redox active compound.

24 . The method of claim 22 , wherein the negolyte comprises an anthraquinone.

25 . The method of claim 24 , wherein the anthraquinone is of formula (I):

wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 is independently selected from H; halo; optionally substituted C 1-6 alkyl; oxo; optionally substituted C

Assignees

• Harvard College

Inventors

• Goulet Marc-Antoni
• Gordon Roy G
• Aziz Michael J

Classifications

• H01M8/225 Primary

  Fuel cells in which the fuel is based on materials comprising particulate active material in the form of a suspension, a dispersion, a fluidised bed or a paste · CPC title

• H01M8/188 Primary

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

• H01M8/18

  Regenerative fuel cells, e.g. redox flow batteries or secondary fuel cells · CPC title

• Y02E60/50

  Fuel cells · CPC title