Electrochemical Cell with Bipolar Faradaic Membrane

Patent metadata

Field	Value
Publication number	US-2016254512-A1
Application number	US-201615055491-A
Country	US
Kind code	A1
Filing date	Feb 26, 2016
Priority date	Feb 27, 2015
Publication date	Sep 1, 2016
Grant date	—

Abstract

An electrochemical cell includes a negative electrode having a first liquid phase having a first active metal, a positive electrode having a second liquid phase having a second active metal, and a liquid electrolyte having a salt of the first active metal and a salt of the second active metal. The electrochemical cell also includes a bipolar faradaic membrane, disposed between the negative electrode and the positive electrode, having a first surface facing the negative electrode and a second surface facing the positive electrode. The bipolar faradaic membrane is configured to allow cations of the first active metal to pass through and to impede cations of the second active metal from transferring from the positive electrode to the negative electrode and is at least partially formed from a material having an electronic conductivity sufficient to drive faradaic reactions at the second surface with the cations of the positive electrode.

First claim

What is claimed is:

1 . An electrochemical cell comprising:
a negative electrode comprising a first liquid phase having a first active metal; a positive electrode, separated from the negative electrode, comprising a second liquid phase having a second active metal; a liquid electrolyte, disposed between the negative electrode and the positive electrode, comprising a salt of the first active metal and a salt of the second active metal; and a bipolar faradaic membrane, disposed between the negative electrode and the positive electrode, having a first surface facing the negative electrode and a second surface facing the positive electrode, the bipolar faradaic membrane configured to allow cations of the first active metal to pass through and configured to impede cations of the second active metal from transferring from the positive electrode to the negative electrode, the bipolar faradaic membrane at least partially formed from a material having an electronic conductivity sufficient to drive faradaic reactions at the second surface with the cations of the positive electrode.

2 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane is configured to have the first surface positively charged and the second surface negatively charged.

3 . The electrochemical cell according to claim 2 , wherein the positively charged first surface and the negatively charged second surface are electrostatically induced.

4 . The electrochemical cell according to claim 1 , wherein the electronic conductivity of the material is greater than or equal to 10 −10 S/m at operating temperature of the electrochemical cell.

5 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane is permeable to passive spectator ions.

6 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane is selected from the group consisting of titanium nitride, zirconium nitride, titanium diboride, graphite, grapheme, metals, metalloids, and combinations thereof.

7 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane further comprises a sintering additive, wherein the sintering additive is selected from the group consisting of magnesium oxide, aluminum oxide, aluminum nitride, silicon nitride, silicon oxide, silicon oxynitride, and combinations thereof.

8 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane is an electronically conductive matrix comprising an insulator and conductive particles, wherein the insulator is selected from the group consisting of magnesium oxide, aluminum oxide, silicon oxide, aluminum nitride, silicon nitride, silicon oxynitride, and/or polymers.

9 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane is selected from the group consisting of nickel-iron foam, copper foam, carbon foam, metal felt, metallic fibers, steels, alloys, and combinations thereof.

10 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane is selected from the group consisting of copper, titanium, iron, nickel, tungsten, tantalum, molybdenum, silicon, and combinations thereof.

11 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane further comprises an electronic pathway across the bipolar faradaic membrane, wherein the electronic pathway is selected from the group consisting of iron, steel, graphite, graphene, and combinations thereof.

12 . The electrochemical cell according to claim 1 , wherein the negative electrode is selected from the group consisting of sodium, lithium, magnesium, calcium, and combinations thereof.

13 . The electrochemical cell according to claim 1 , wherein the positive electrode is selected from the group consisting of lead, zinc, tin, bismuth, antimony, and combinations thereof.

14 . The electrochemical cell according to claim 1 , wherein the bipolar faradaic membrane is in direct contact with the negative electrode.

15 . The electrochemical cell according to claim 1 , wherein the electrolyte is between the negative electrode and the bipolar faradaic membrane and between the bipolar faradaic membrane and the positive electrode.

16 . The electrochemical cell according to claim 1 , wherein the electrochemical cell is a Li/PbCl 2 electrochemical cell.

17 . The electrochemical cell according to claim 1 , wherein the negative electrode is an alloy and the electrochemical cell is a LiPb∥PbCl 2 electrochemical cell, a LiBi∥PbCl 2 electrochemical cell, a LiPb∥SnCl 2 electrochemical cell, a LiSn∥SnCl 2 electrochemical cell, a Li—Pb∥PbBr 2 electrochemical cell, a Mg—Pb∥PbCl 2 electrochemical cell, or a Mg—Sn∥PbCl 2 electrochemical cell.

18 . The electrochemical cell according to claim 1 , wherein the negative electrode is contained in an electronically conductive container.

19 . The electrochemical cell according to claim 1 , wherein the electrolyte is selected from the group consisting of LiCl—KCl, LiBr—KBr, and LiCl—LiBr—KBr.

20 . A method of exchanging electrical energy with an external circuit, the method comprising:
providing an electrochemical cell according to claim 1 ; connecting the electrochemical cell to the external circuit; and operating the external circuit so as to drive transfer of electrons between the negative electrode and the positive electrode.

Assignees

• Massachusetts Inst Technology
• Total Marketing Services

Inventors

• Yin Huayi
• Chen Fei
• Chung Brice Hoani Valentin
• Ouchi Takanari
• Sadoway Donald Robert

Classifications

• H01M4/387

  Tin or alloys based on tin · CPC title

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title

• H01M10/399 Primary

  Cells with molten salts · CPC title

• H01M2300/0057

  Chlorides · CPC title

• H01M4/38

  of elements or alloys · CPC title