Flow battery balancing cells having a bipolar membrane and methods for use thereof

Patent metadata

Field	Value
Publication number	US-2016308235-A1
Application number	US-201615098276-A
Country	US
Kind code	A1
Filing date	Apr 13, 2016
Priority date	Apr 14, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

Parasitic reactions, such as production of hydrogen and oxidation by oxygen, can occur under the operating conditions of flow batteries and other electrochemical systems. Such parasitic reactions can undesirably impact operating performance by altering the pH and/or state of charge of one or both electrolyte solutions in a flow battery. Electrochemical balancing cells configured for addressing the effects of parasitic reactions can include: a first chamber containing a first electrode, a second chamber containing a second electrode, a third chamber disposed between the first chamber and the second chamber, an ion-selective membrane forming a first interface between the first chamber and the third chamber, and a bipolar membrane forming a second interface between the second chamber and the third chamber. Such electrochemical balancing cells can be placed in fluid communication with at least one half-cell of a flow battery.

First claim

What is claimed is the following:

1 . An electrochemical balancing cell comprising:
a first chamber containing a first electrode; a second chamber containing a second electrode; a third chamber disposed between the first chamber and the second chamber; an ion-selective membrane forming a first interface between the first chamber and the third chamber; and a bipolar membrane forming a second interface between the second chamber and the third chamber.

2 . The electrochemical balancing cell of claim 1 , wherein the ion-selective membrane comprises a cation-exchange material.

3 . The electrochemical balancing cell of claim 2 , wherein the cation-exchange material comprises a sulfonated, perfluorinated polymer.

4 . The electrochemical balancing cell of claim 1 , wherein the first electrode is a negative electrode and the second electrode is a positive electrode.

5 . The electrochemical balancing cell of claim 1 , wherein the first electrode is a positive electrode and the second electrode is a negative electrode.

6 . The electrochemical balancing cell of claim 1 , wherein at least one of the first chamber, the second chamber, and the third chamber contain an aqueous electrolyte solution.

7 . A flow battery system comprising:
a first half-cell containing a first electrolyte solution; and a second half-cell containing a second electrolyte solution;
wherein at least one of the first half-cell and the second half-cell is in fluid communication with an electrochemical balancing cell comprising:
a first chamber containing a first electrode;
a second chamber containing a second electrode;
a third chamber disposed between the first chamber and the second chamber;
an ion-selective membrane forming a first interface between the first chamber and the third chamber; and
a bipolar membrane forming a second interface between the second chamber and the third chamber.

8 . The flow battery system of claim 7 , wherein the ion-selective membrane comprises a cation-exchange material.

9 . The flow battery system of claim 7 , wherein the first electrode is a negative electrode and the second electrode is a positive electrode.

10 . The flow battery system of claim 9 , wherein either the first half-cell or the second half-cell is in fluid communication with both the first chamber and the second chamber, and the third chamber contains an aqueous electrolyte solution.

11 . The flow battery system of claim 9 , wherein either the first half-cell or the second half-cell is in fluid communication with the third chamber, and the first chamber and the second chamber independently contain water or an aqueous solution.

12 . The flow battery system of claim 7 , wherein at least one of the first electrolyte solution and the second electrolyte solution comprises an aqueous electrolyte solution.

13 . The flow battery system of claim 7 , wherein at least one of the first electrolyte solution and the second electrolyte solution comprises a coordination complex as an active material.

14 . A method comprising:
providing an electrochemical balancing cell comprising:
a first chamber containing a first electrode;
a second chamber containing a second electrode;
a third chamber disposed between the first chamber and the second chamber;
an ion-selective membrane forming a first interface between the first chamber and the third chamber; and
a bipolar membrane forming a second interface between the second chamber and the third chamber;
introducing a first electrolyte solution comprising a first active material into the third chamber; introducing water or an aqueous solution independently into the first chamber and the second chamber; applying a potential across the electrochemical balancing cell so as to induce a current therein, such that the second electrode is a positive electrode and the first electrode is a negative electrode; and converting water into protons and hydroxide ions at the bipolar membrane;
wherein the protons migrate into the first electrolyte solution in the third chamber and the hydroxide ions migrate into the water or the aqueous solution in the second chamber.

15 . The method of claim 14 , further comprising:
placing the electrochemical balancing cell in fluid communication with at least one half-cell of a flow battery; and transferring the first electrolyte solution between the electrochemical balancing cell and the flow battery.

16 . The method of claim 15 , wherein the first electrolyte solution is transferred to a negative half-cell of the flow battery.

17 . The method of claim 15 , wherein the first electrolyte solution is transferred to a positive half-cell of the flow battery.

18 . The method of claim 15 , wherein the first electrolyte solution comprises an aqueous solution.

19 . A method comprising:
providing an electrochemical balancing cell comprising:
a first chamber containing a first electrode;
a second chamber containing a second electrode;
a third chamber disposed between the first chamber and the second chamber;
an ion-selective membrane forming a first interface between the first chamber and the third chamber; and
a bipolar membrane forming a second interface between the second chamber and the third chamber;
introducing a first electrolyte solution comprising a first active material into the first chamber and the second chamber; introducing an aqueous electrolyte solution into the third chamber; applying a potential across the electrochemical balancing cell so as to induce a current therein, such that the second electrode is a positive electrode and the first electrode is a negative electrode; and converting water into protons and hydroxide ions at the bipolar membrane;
wherein the protons migrate into the aqueous electrolyte solution in the third chamber and the hydroxide ions migrate into the first electrolyte solution in the second chamber.

20 . The method of claim 19 , further comprising:
placing the electrochemical balancing cell in fluid communication with at least one half-cell of a flow battery; and transferring the first electrolyte solution between the electrochemical balancing cell and the flow battery.

21 . The method of claim 20 , wherein the first electrolyte solution is transferred to a negative half-cell of the flow battery.

22 . The method of claim 20 , wherein the first electrolyte solution is transferred to a positive half-cell of the flow battery.

23 . The method of claim 20 , wherein the first electrolyte solution comprises an aqueous solution.

Assignees

• Lockheed Martin Advanced Energy Storage Llc

Inventors

• Reece Steven Y

Classifications

• H01M8/04186

  of liquid-charged or electrolyte-charged reactants · CPC title

• H01M8/188 Primary

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

• H01M8/20

  Indirect fuel cells, e.g. fuel cells with redox couple being irreversible (H01M8/18 takes precedence) · CPC title

• H01M8/1023

  having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes · CPC title

• H01M8/04276

  Arrangements for managing the electrolyte stream, e.g. heat exchange · CPC title