Electrochemical cells having designed flow fields and methods for producing the same

Patent metadata

Field	Value
Publication number	US-2017294662-A1
Application number	US-201615093604-A
Country	US
Kind code	A1
Filing date	Apr 7, 2016
Priority date	Apr 7, 2016
Publication date	Oct 12, 2017
Grant date	—

Abstract

Electrochemical cells can include flow channels designed to provide an electrolyte solution more efficiently to an electrode or ionically conductive separator. Such electrochemical cells can include an ionically conductive separator disposed between a first half-cell and a second half-cell, a first bipolar plate in the first half-cell, and a second bipolar plate in the second half-cell. At least one of the first bipolar plate and the second bipolar plate are a composite containing a conductive material and a blocking material. The blocking material defines a plurality of flow channels that are spaced apart from one another and extend laterally through the composite with respect to the ionically conductive separator. The plurality of flow channels are also in fluid communication with one another in the composite. Such electrochemical cells can be incorporated in electrochemical stacks and/or be fluidly connected to a fluid inlet manifold and a fluid outlet manifold.

First claim

What is claimed is the following:

1 . An electrochemical cell comprising:
an ionically conductive separator disposed between a first half-cell and a second half-cell; and a first bipolar plate in the first half-cell and a second bipolar plate in the second half-cell, at least one of the first bipolar plate and the second bipolar plate being a composite comprising a conductive material and a blocking material;
wherein the blocking material defines a plurality of flow channels that are spaced apart from one another and extend laterally through the composite with respect to the ionically conductive separator; and
wherein the plurality of flow channels are in fluid communication with one another in the composite.

2 . The electrochemical cell of claim 1 , wherein the conductive material comprises a non-woven carbon paper, a woven carbon cloth, a carbon felt, or a carbon foam.

3 . The electrochemical cell of claim 1 , wherein the plurality of flow channels are substantially parallel to one another in the composite.

4 . The electrochemical cell of claim 1 , further comprising:
a first electrode in the first half-cell and a second electrode in the second half-cell, the first electrode intervening between the first bipolar plate and the ionically conductive separator, and the second electrode intervening between the second bipolar plate and the ionically conductive separator.

5 . The electrochemical cell of claim 4 , wherein the first bipolar plate is in contact with the first electrode, and the second bipolar plate is in contact with the second electrode.

6 . The electrochemical cell of claim 1 , wherein the first bipolar plate and the second bipolar plate are in contact with opposing sides of the ionically conductive separator.

7 . The electrochemical cell of claim 1 , wherein the blocking material comprises a polymer material.

8 . The electrochemical cell of claim 7 , wherein the polymer material comprises a thermoplastic polymer.

9 . The electrochemical cell of claim 1 , wherein the blocking material is impregnated into the conductive material.

10 . The electrochemical cell of claim 1 , wherein the blocking material comprises a layer upon the conductive material.

11 . The electrochemical cell of claim 1 , further comprising:
a fluid inlet manifold configured to provide a first electrolyte solution to the first bipolar plate and a second electrolyte solution to the second bipolar plate; and a fluid outlet manifold configured to withdraw the first electrolyte solution from the first bipolar plate and the second electrolyte solution from the second bipolar plate;
wherein the fluid inlet manifold and the fluid outlet manifold are configured to provide and to withdraw the first electrolyte solution and the second electrolyte solution from alternating flow channels within the composite.

12 . The electrochemical cell of claim 11 , wherein the fluid inlet manifold and the fluid outlet manifold are configured to provide and to withdraw the first electrolyte solution and the second electrolyte solution on opposing lateral faces of the first bipolar plate and the second bipolar plate.

13 . The electrochemical cell of claim 11 , further comprising:
one or more frame layers configured to hold the first bipolar plate in the first half-cell and to provide a fluidic seal therein, and one or more frame layers configured to hold the second bipolar plate in the second half-cell and to provide a fluidic seal therein;
wherein at least one of the frame layers in the first half-cell is configured to provide the first electrolyte solution to the first bipolar plate, and at least one of the frame layers in the second half-cell is configured to provide the second electrolyte solution to the second bipolar plate.

14 . The electrochemical cell of claim 1 , further comprising:
one or more frame layers configured to hold the first bipolar plate in the first half-cell and to provide a fluidic seal therein, and one or more frame layers configured to hold the second bipolar plate in the second half-cell and to provide a fluidic seal therein;

15 . An electrochemical stack comprising:
a plurality of the electrochemical cells of claim 1 abutted together with one another.

16 . The electrochemical stack of claim 15 , further comprising:
an additional conductive layer disposed between adjacent electrochemical cells.

17 . The electrochemical stack of claim 15 , wherein the electrochemical stack is present in a flow battery.

18 . The electrochemical stack of claim 15 , further comprising:
a fluid inlet manifold configured to provide a first electrolyte solution to the first bipolar plate and a second electrolyte solution to the second bipolar plate; and a fluid outlet manifold configured to withdraw the first electrolyte solution from the first bipolar plate and the second electrolyte solution from the second bipolar plate;
wherein the fluid inlet manifold and the fluid outlet manifold are configured to provide and to withdraw the first electrolyte solution and the second electrolyte solution from alternating flow channels within the composite.

19 . A method comprising:
impregnating a blocking material into a portion of a conductive material to form a composite; and fabricating an electrochemical cell comprising a first bipolar plate in a first half-cell and a second bipolar plate in a second half-cell, the first half-cell and the second half-cell being separated by an ionically conductive separator;
wherein at least one of the first bipolar plate and the second bipolar plate comprises the composite; and
wherein the blocking material defines a plurality of flow channels that are spaced apart from one another and extend laterally through the composite with respect to the ionically conductive separator;
wherein the plurality of flow channels are in fluid communication with one another in the composite.

20 . The method of claim 19 , wherein the electrochemical cell is fabricated from rolled source materials in a continuous production line.

21 . The method of claim 20 , wherein the composite and the plurality of flow channels therein are also formed in the continuous production line before fabricating the electrochemical cell.

22 . The method of claim 19 , wherein impregnating the blocking material comprises thermally impregnating a thermoplastic polymer into the conductive material.

23 . The method of claim 19 , further comprising:
abutting a plurality of the electrochemical cells together with one another to form an electrochemical stack.

24 . A method comprising:
disposing a blocking material in a layer upon a conductive material to form a composite; removing a portion of the blocking material from the layer to define a plurality of flow channels that are spaced apart from one another; and fabricating an electrochemical cell comprising a first bipolar plate in a first half-cell and a second bipolar plate in a second half-cell, the first half-cell and the second half-cell being separated by an ionically conductive separator;
wherein at least one of the first bipolar plate and the second bipolar plate comprises the composite; and
wherein the plurality of flow channels extend laterally through the composite with respect to the ionically conductive separator;
wherein the plurality of flow channels are in fluid communication with one another in the composite.

25 . The m

Assignees

• Lockheed Martin Advanced Energy Storage Llc

Inventors

• Madden Thomas H
• Badrinarayanan Paravastu
• Warrington Curtis
• Puranam Srivatsava

Classifications

• H01M8/2483

  characterised by internal manifolds · CPC title

• H01M8/0258 Primary

  characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant · CPC title

• H01M8/0226

  in the form of mixtures · CPC title

• H01M8/188

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

• H01M8/04276

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