Halogen complexing agents bound to the cathode surface in static zinc halide cells.

Abstract

formula Q + (R A )(R B )(R C )(R D )X - A bipolar electrode is disclosed that includes a cathode substrate loaded with a halogen complexing agent having the structure: The bipolar electrode also includes a bipolar electrode plate having a cathode surface and an anode surface, the cathode surface being opposite the anode surface. The cathode surface is at least partially in contact with the cathode substrate. Electrochemical cells and battery stacks that include the bipolar electrode, as well as methods for manufacturing the bipolar electrode, are also disclosed. TIFF2024512677000004.tif103170

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 168,699, filed March 31, 2021, the disclosure of which is incorporated by reference in its entirety herein.

[0002] Technical Field Rechargeable batteries are described herein. In particular, static zinc halide batteries are described. [Background technology]

[0003] background Zinc halide batteries were developed as devices for storing electrical energy. Traditional zinc halide batteries (e.g., zinc bromide batteries) employ bipolar electrodes placed in a static, i.e., non-flowing, aqueous zinc bromide solution. The process of charging and discharging electrical current in a zinc halide battery generally involves the transfer of electrical current through the Zn in the zinc halide electrolyte. 2+ / Zn(s) and X - This is achieved through the reaction of a redox couple such as ZnO / X2. When a battery is charged with an electric current, the following chemical reactions take place: Zinc 2+ +2e - →Zn 2X - →X2+2e - , where X is a halogen (e.g., Cl, Br, or I). Conversely, when the battery discharges current, the following chemical reaction occurs: Zn → Zn 2+ +2e - X2+2e - →2X - .

[0004] These zinc halide batteries are formed in bipolar electrochemical cell stacks, where each electrode contains two poles, such that an anodic reaction occurs on one side of the electrode and a cathodic reaction occurs on the other side of the electrode. In this case, the bipolar electrodes are often configured as plates, and the cell stacks are assembled to form a prismatic shape. During charging and discharging of the bipolar battery, the electrode plates act as conductors for adjacent cells, i.e., each electrode plate acts as an anode for one cell and a cathode for the adjacent cell. In this prismatic battery shape, the entire surface area of ​​the electrode plates separating adjacent electrochemical cells transfers current from cell to cell.

[0005] Thus, when a conventional bipolar zinc halide battery is charged, zinc metal is electrolytically deposited on the anode side of the bipolar electrode plates while molecular halogen species are formed on the cathode side of the electrode plates, and when the battery is discharged, the electrodeposited zinc metal oxidizes and releases electrons which are conducted through the electrode plates to reduce the molecular halogen species to form halide anions.

[0006] The cathode of a conventional zinc-bromine battery must store bromine or polybromides during charging so that they are available during discharge. However, current zinc-bromine batteries rely on physical trapping of bromine or polybromides in a porous cathode, which is difficult when concentration and density gradients can cause bromine and polybromides to migrate away from the cathode and become unavailable during discharge. This is particularly problematic in large static zinc halide batteries, because the polybromides must remain stored in the cathode for hours at a time without moving around. Summary of the Invention

[0007] overview Described herein is a bipolar electrode having a cathode substrate loaded with a halogen complexing agent.

[0008] One aspect of the present disclosure is to provide a method for producing a bipolar electrode plate having a cathode surface and an anode surface, the cathode surface being opposite the anode surface; a cathode substrate loaded with a halogen complexing agent, the cathode surface being at least partially in contact with the cathode substrate; A bipolar electrode comprising: The halogen complexing agent is represented by the formula (I): Q + (R A )(R B )(R C )(R D )X - wherein the variables Q, R A , R B , R C , R D and X is as defined herein. Concerning bipolar electrodes.

[0009] In some embodiments, the cathode substrate is oxidized, carbon-treated, graphitized, activated, or any combination thereof. The cathode substrate may be oxidized, carbon-treated, graphitized, activated, or any combination thereof prior to being loaded with the halogen complexing agent. In some embodiments, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0010] In some embodiments, the cathode substrate comprises carbon felt. The carbon felt may be oxidized, carbon-treated, graphitized, activated, or any combination thereof. In some embodiments, the carbon felt has a thickness of about 2 mm to about 10 mm. The carbon felt may be loaded with a halogen complexing agent at a concentration of about 0.1 to about 100 milligrams per gram of carbon felt.

[0011] In some embodiments, the cathode substrate comprises compressed carbon powder, which may be activated carbon, carbon black, expanded graphite, graphite, or a combination of two or more thereof.

[0012] In some embodiments, the cathode surface is at least partially attached to the cathode substrate using an adhesive, an electrically conductive binder, a tape, a mechanical cage, or a combination thereof.

[0013] In some embodiments, the loaded cathodic substrate is a cathodic substrate chemically bonded to a halogen complexing agent, in some embodiments, the cathodic substrate is chemically bonded to a monomer of the halogen complexing agent, in some embodiments, the cathodic substrate is chemically bonded to a polymer of the halogen complexing agent.

[0014] In some embodiments, the halogen complexing agent is triethylammonium (12-dodecylphosphonate) bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium (12-dodecylphosphonate) chloride, pyridinium (12-dodecylphosphonate) bromide, N,N-dimethyl-N-octadecylammonium (12-dodecylphosphonate) bromide, 1-methyl-3-(dodecylphosphonate) imidazolium bromide, or 1-methyl-3-(hexylphosphonate) imidazolium bromide.

[0015] In some embodiments, the bipolar electrode plate comprises a titanium material, which may be at least partially coated with titanium carbide, hi some embodiments, the bipolar electrode plate comprises titanium, TiC, TiN, graphite, or an electrically conductive plastic.

[0016] A second aspect of the present disclosure relates to a method for producing a bipolar electrode, the method comprising the steps of: mixing a halogen complexing agent and a solvent to form a mixture; contacting a cathode substrate with the mixture to form a loaded cathode substrate by loading the mixture on the cathode substrate; and contacting at least a portion of the loaded cathode substrate with a cathode side of a bipolar electrode plate to form a bipolar electrode. The halogen complexing agent is represented by the formula (I):Q + (R A )(R B )(R C )(R D )X - wherein the variables Q, R A , R B , R C , R D and X is as defined herein.

[0017] In some embodiments, the method further comprises drying the loaded cathode substrate.

[0018] In some embodiments, the method further comprises sonicating the mixture prior to, during, or both before and during contacting the cathode substrate with the mixture.

[0019] In some embodiments, the method further comprises treating the cathode substrate, the treatment being selected from oxidation, carbon treatment, activation, graphite treatment, or any combination thereof, hi some embodiments, the treatment step is performed prior to, during, or both prior to and during contacting the cathode substrate with the mixture of halogen complexing agent and solvent.

[0020] In some embodiments, the solvent is water, an alcohol, or a combination thereof.

[0021] The halogen complexing agent in the mixture is monomeric. In some embodiments, the loaded cathodic substrate is a cathodic substrate chemically bonded to the halogen complexing agent. In some embodiments, the cathodic substrate is chemically bonded to the halogen complexing agent in monomeric form. In some embodiments, the cathodic substrate is chemically bonded to a polymer of the halogen complexing agent.

[0022] A third aspect of the present disclosure is a bipolar electrode plate having a cathode surface and an anode surface, the cathode surface being opposite the anode surface; and a cathode substrate loaded with a halogen complexing agent, the cathode surface being at least partially in contact with the cathode substrate; A bipolar electrode including: Aqueous zinc halide electrolyte and An electrochemical cell comprising: The halogen complexing agent is represented by the formula (I): Q + (R A )(R B )(R C )(R D )X - wherein the variables Q, R A , R B , R C , R D and X is as defined herein. Concerning electrochemical cells.

[0023] In some embodiments, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0024] In some embodiments, the halogen complexing agent is triethylammonium (12-dodecylphosphonate) bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium (12-dodecylphosphonate) chloride, pyridinium (12-dodecylphosphonate) bromide, N,N-dimethyl-N-octadecylammonium (12-dodecylphosphonate) bromide, 1-methyl-3-(dodecylphosphonate) imidazolium bromide, or 1-methyl-3-(hexylphosphonate) imidazolium bromide.

[0025] In some embodiments, the bipolar electrode plate comprises a titanium material, which may be at least partially coated with titanium carbide, hi some embodiments, the bipolar electrode plate comprises titanium, TiC, TiN, graphite, or an electrically conductive plastic.

[0026] In some embodiments, the aqueous zinc halide electrolyte of the electrochemical cell comprises about 25 wt.% to about 70 wt.% ZnBr2, about 5 wt.% to about 50 wt.% water, and about 0.05 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0027] In some embodiments, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 40 wt.% ZnBr2, about 25 wt.% to about 50 wt.% water, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and about 0.5 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0028] In some embodiments, the one or more quaternary ammonium agents are ammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, trimethylpropylammonium bromide, triethylmethylammonium chloride, trimethylpropylammonium chloride, butyltrimethylammonium chloride, trimethylethylammonium chloride, N-methyl-N-ethylmorpholinium bromide, N-methyl-N-ethylmorpholinium bromide (MEMBr), 1-ethyl-1-methylmorpholinium bromide, N-methyl-N-butylmorpholinium bromide, N-methyl-N-ethylpyrrolidinium bromide, N,N,N-triethyl-N-propylammonium bromide, N-ethyl-N-propylpyrrolidinium bromide, N-propyl-N-butylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, 1-methyl- The quaternary agent may be selected from the group consisting of 1-butylpyrrolidinium, N-ethyl-N-(2-chloroethyl)pyrrolidinium bromide, N-methyl-N-hexylpyrrolidinium bromide, N-methyl-N-pentylpyrrolidinium bromide, N-ethyl-N-pentylpyrrolidinium bromide, N-ethyl-N-butylpyrrolidinium bromide, trimethylene-bis(N-methylpyrrolidinium) dibromide, N-butyl-N-pentylpyrrolidinium bromide, N-methyl-N-propylpyrrolidinium bromide, N-propyl-N-pentylpyrrolidinium bromide, 1-ethyl-4-methylpyridinium bromide, 1-ethyl-2-methylpyridinium bromide, 1-butyl-3-methylpyridinium bromide, cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, cetyltriethylammonium bromide, and any combination thereof.

[0029] In some embodiments, the one or more quaternary ammonium agents comprise alkyl-substituted pyridinium chlorides, alkyl-substituted pyridinium bromides, alkyl-substituted morpholinium chlorides, alkyl-substituted morpholinium bromides, alkyl-substituted pyrrolidinium chlorides, alkyl-substituted pyrrolidinium bromides, or any combination thereof.

[0030] A fourth aspect of the present disclosure is A pair of terminal assemblies; at least one bipolar electrode interposed between the pair of terminal assemblies; A battery stack comprising: The bipolar electrodes are A bipolar electrode plate; a cathode substrate loaded with a halogen complexing agent; an aqueous zinc halide electrolyte in contact with the bipolar electrode plates and the cathode substrate; Including, The halogen complexing agent is represented by the formula (I): Q + (R A )(R B )(R C )(R D )X - wherein the variables Q, R A , R B , R C , R D and X is as defined herein. Regarding the battery stack.

[0031] In some embodiments, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0032] In some embodiments, the halogen complexing agent is triethylammonium (12-dodecylphosphonate) bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium (12-dodecylphosphonate) chloride, pyridinium (12-dodecylphosphonate) bromide, N,N-dimethyl-N-octadecylammonium (12-dodecylphosphonate) bromide, 1-methyl-3-(dodecylphosphonate) imidazolium bromide, or 1-methyl-3-(hexylphosphonate) imidazolium bromide.

[0033] In some embodiments, the bipolar electrode plates include a titanium material.

[0034] In some embodiments, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 70 wt.% ZnBr2, about 5 wt.% to about 50 wt.% water, and about 0.05 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0035] In some embodiments, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 40 wt.% ZnBr2, about 25 wt.% to about 50 wt.% water, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and about 0.5 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0036] In some embodiments, the one or more quaternary ammonium agents are ammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, trimethylpropylammonium bromide, triethylmethylammonium chloride, trimethylpropylammonium chloride, butyltrimethylammonium chloride, trimethylethylammonium chloride, N-methyl-N-ethylmorpholinium bromide, N-methyl-N-ethylmorpholinium bromide (MEMBr), 1-ethyl-1-methylmorpholinium bromide, N-methyl-N-butylmorpholinium bromide, N-methyl-N-ethylpyrrolidinium bromide, N,N,N-triethyl-N-propylammonium bromide, N-ethyl-N-propylpyrrolidinium bromide, N-propyl-N-butylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, 1-methyl- The quaternary agent may be selected from the group consisting of 1-butylpyrrolidinium, N-ethyl-N-(2-chloroethyl)pyrrolidinium bromide, N-methyl-N-hexylpyrrolidinium bromide, N-methyl-N-pentylpyrrolidinium bromide, N-ethyl-N-pentylpyrrolidinium bromide, N-ethyl-N-butylpyrrolidinium bromide, trimethylene-bis(N-methylpyrrolidinium) dibromide, N-butyl-N-pentylpyrrolidinium bromide, N-methyl-N-propylpyrrolidinium bromide, N-propyl-N-pentylpyrrolidinium bromide, 1-ethyl-4-methylpyridinium bromide, 1-ethyl-2-methylpyridinium bromide, 1-butyl-3-methylpyridinium bromide, cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, cetyltriethylammonium bromide, and any combination thereof.

[0037] In some embodiments, the one or more quaternary ammonium agents comprise alkyl-substituted pyridinium chlorides, alkyl-substituted pyridinium bromides, alkyl-substituted morpholinium chlorides, alkyl-substituted morpholinium bromides, alkyl-substituted pyrrolidinium chlorides, alkyl-substituted pyrrolidinium bromides, or any combination thereof.

[0038] In some embodiments, the self-discharge rate of the battery stacks described herein is about 29% to about 34% lower in a single cycle compared to an equivalent battery stack that does not include a halogen complexing agent. [Brief description of the drawings]

[0039] These and other features, aspects, and advantages of the devices described herein will become better understood from the following detailed description taken in conjunction with the accompanying drawings.

[0040] [Figure 1] FIG. 1 shows an exploded view of an electrochemical cell according to one aspect of the invention described. [Diagram 2] 2A and 2B are front and side views, respectively, of a bipolar electrode according to one aspect of the invention described. [Diagram 3] 1 shows an exploded view of a bipolar electrode according to one aspect of the invention described. [Figure 4] Figure 4A shows a front view and Figure 4B shows an exploded view of a bipolar electrode according to one aspect of the described invention. [Diagram 5] 2 shows a view of the backside of an electrode plate having sandblasted areas 217 according to one aspect of the invention described. [Figure 6] 6A and 6B show front and side views, respectively, of a cathode cage according to one aspect of the described invention. [Figure 7] 7A and 7B show, respectively, a front view of a cathode cage according to one aspect of the described invention and a close-up view of the cathode cage material with through holes. [Figure 8] 1 shows a cross-sectional view of a portion of an electrochemical cell including the interface between the front surface of a bipolar electrode plate (including a cathode assembly mounted thereto) and the back surface of a second electrode plate or the inner surface of a terminal end plate according to one aspect of the invention described. [Figure 9] 1A-1D show front, side, and top perspective views of loaded carbon felt for use as a cathode substrate according to one aspect of the invention described. [Figure 10] FIG. 1 shows a top perspective view of a terminal assembly for a bipolar battery according to one aspect of the invention described. [Figure 11] 11 shows an exploded view of the terminal assembly of FIG. 10 in accordance with aspects of the invention described. [Figure 12] FIG. 2 shows a side view of a battery stack according to one aspect of the invention described. [Figure 13] FIG. 13 shows an exploded view of the battery stack of FIG. 12 according to one aspect of the invention described. [Figure 14] FIG. 13 shows a front view of a battery frame member for use in the battery stack of FIG. 12 according to one aspect of the invention described. [Figure 15] FIG. 15 shows a close-up side view of the bottom of the battery frame member of FIG. 14 according to one aspect of the invention described. [Figure 16] 1 shows examples of self-assembled monolayers bound to an oxidized surface (eg, a cathode substrate) using two different examples of halogen complexing agents described herein. [Figure 17] FIG. 1 shows a plot of average discharge capacity versus cycle index for three cell populations that include either an untreated control felt ("Untreated") or felt loaded with one of the exemplary halogen complexing agents described herein ("Silane-treated" or "Phosphate-treated"). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] Detailed Description The embodiments of the present disclosure will be described in detail with reference to the drawings in which similar reference numbers identify similar or identical elements. It should be understood that the disclosed embodiments are merely examples of the disclosure that can be embodied in various forms. Well-known functions or structures are not described in detail to avoid obscuring the present disclosure with unnecessary detail. Therefore, the details of the specific structure and function disclosed in this specification should not be interpreted as limitations, but merely as a basis for the claims, and as a representative basis for teaching those skilled in the art to employ the present disclosure in various forms in substantially any suitable detailed structure.

[0042] I. Definition As used herein, the terms "electrochemical cell" or "cell" are used interchangeably to refer to a device capable of either generating electrical energy from a chemical reaction or promoting a chemical reaction through the introduction of electrical energy. The electrochemical cell may be a bipolar electrochemical cell, a terminal electrochemical cell, or a laboratory cell.

[0043] As used herein, the term "battery" includes an electrical storage device that includes at least one electrochemical cell. For example, a battery may include 40 electrochemical cells in series. "Secondary batteries" are rechargeable, whereas "primary batteries" are not. For secondary batteries described herein, the anode of the battery is designated as the positive electrode during discharge and as the negative electrode during charging.

[0044] As used herein, "electrolyte" refers to a substance that acts as an electrically conductive medium. For example, an electrolyte facilitates the movement of anions and cations within a cell. Electrolytes include mixtures of substances such as aqueous solutions of metal halide salts (e.g., ZnBr2, ZnCl2, etc.).

[0045] As used herein, the term "electrode" refers to an electrical conductor used to make contact with a non-metallic portion of a circuit (e.g., a semiconductor, an electrolyte, or a vacuum). An electrode can be either an anode or a cathode.

[0046] As used herein, the term "anode" refers to the negative electrode from which electrons flow during the discharge phase in a battery. The anode is also the electrode that undergoes chemical oxidation during the discharge phase. However, in secondary or rechargeable batteries, the anode is the electrode that undergoes chemical reduction during the charge phase of the cell. The anode is formed from an electrically conductive or semiconductive material, such as a metal (e.g., titanium or TiC-coated titanium), a metal oxide, a metal alloy, a metal composite, a semiconductor, and the like.

[0047] As used herein, the term "cathode" refers to the positive electrode into which electrons flow during the discharge phase in a battery. The cathode is also the electrode that undergoes chemical reduction during the discharge phase. However, in secondary or rechargeable batteries, the cathode is the electrode that undergoes chemical oxidation during the charge phase of the cell. Cathodes are formed from electrically conductive or semiconductive materials, such as metals, metal oxides, metal alloys, metal composites, semiconductors, and the like.

[0048] As used herein, the term "bipolar electrode" refers to an electrode that functions as an anode in one cell and a cathode in the other cell. For example, in a battery, a bipolar electrode functions as an anode in one cell and a cathode in an adjacent cell. In some examples, a bipolar electrode includes two faces, a cathode face and an anode face, the two faces being connected by an electrically conductive material. For example, a bipolar electrode plate can have opposing faces, where one face is an anode face and the other face is a cathode face, and the electrically conductive material is the thickness of the plate between the opposing faces.

[0049] As used herein, the term "halide" refers to a binary compound of a halogen with another element or radical that is less electronegative (or more electropositive) than the halogen, resulting in a fluoride, chloride, bromide, iodide, or astatide compound.

[0050] As used herein, the term "halogen" refers to any of the elements fluorine, chlorine, bromine, iodine, and astatine that occupy Group VIIA (17) of the periodic table. Halogens are reactive nonmetallic elements that form highly acidic compounds with hydrogen and can give rise to simple salts.

[0051] As used herein, the term "anion" refers to any chemical entity that has one or more permanent negative charges. Examples of anions include, but are not limited to, fluoride, chloride, bromide, iodide, arsenate, phosphate, arsenite, hydrogen phosphate, dihydrogen phosphate, sulfate, nitrate, hydrogen sulfate, nitrite, thiosulfate, sulfite, perchlorate, iodate, chlorate, bromate, chlorite, hypochlorite, hypobromite, carbonate, chromate, bicarbonate (bicarbonate), dichromate, acetate, formate, cyanide, amide, cyanate, peroxide, thiocyanate, oxalate, hydroxide, and permanganate.

[0052] As used herein, "titanium material" refers to titanium (in any oxidation state), TiC, alloys of TiC, e.g., TiC x M (wherein x is 0, 1, 2, 3, or 4 and M is a metal), titanium carbohyride, non-stoichiometric titanium-carbon compounds, and combinations thereof.

[0053] As used herein, "titanium carbide" is used interchangeably with "titanium carbide material" and includes TiC, alloys of TiC, e.g., TiC xM (wherein x is 0, 1, 2, 3, or 4 and M is a metal), titanium carbohydrides, non-stoichiometric titanium-carbon compounds, and combinations thereof.

[0054] As used herein, the term "zinc metal" refers to Zn(0) or Zn o Zinc is also commonly known as zinc.

[0055] As used herein, the term "quaternary ammonium agent" refers to any compound, salt, or material that contains a quaternary nitrogen atom. For example, quaternary ammonium agents include ammonium halides (e.g., NH4Br, NH4Cl, or any combination thereof), tetraalkylammonium halides (e.g., tetramethylammonium bromide, tetramethylammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, alkyl-substituted pyridinium halides, alkyl-substituted morpholinium halides, combinations thereof, etc.), heterocyclic ammonium halides (e.g., alkyl-substituted pyrrolidinium halides (e.g., N-methyl-N-ethylpyrrolidinium halides or N-ethyl-N-methylpyrrolidinium halides), alkyl-substituted pyridinium halides, alkyl-substituted morpholinium halides, viologens with at least one quaternary nitrogen atom, combinations thereof, etc.), or any combination thereof. Tetraalkylammonium halides may be symmetrically or asymmetrically substituted with respect to the substituent of the quaternary nitrogen atom.

[0056] As used herein, the term "weight percent" and its abbreviations "wt.%" or "wt%" are used interchangeably to refer to 100 times the mass of one or more components divided by the total mass of a mixture or product containing those components: TIFF2024512677000002.tif8128

[0057] When referring to a component or ingredient concentration for an electrolyte, as described herein, wt.% (or wt%) is based on the total weight of the electrolyte.

[0058] When an element or layer is referred to as "in contact with," "engaged with," "connected to," "attached to," or "bonded to" another element or layer, it may be directly in contact with, engaged with, connected to, attached to, or bonded to the other element or layer, or there may be intervening elements or layers present. In contrast, when an element is referred to as "directly in contact with," "directly engaged with," "directly connected to," "directly attached to," or "directly bonded to" another element or layer, there must not be intervening elements or layers present. Other words used to describe relationships between elements should be interpreted similarly (e.g., "between" and "directly between," "adjacent" and "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0059] Terms such as top, bottom, upper, lower, right, left, etc. may be used herein to describe the location of various elements relative to other elements. These terms represent the location of elements in an exemplary configuration. However, it will be apparent to one of ordinary skill in the art that battery frame members may be rotated in space without departing from the present disclosure, and thus these terms should not be used to limit the scope of the present disclosure.

[0060] As used herein, a "plurality" refers to two or more of the listed elements. In some embodiments, a plurality refers to three or more, four or more, or five or more of the listed elements.

[0061] As used herein, "chemically compatible" refers to a material that does not interfere with the chemistry of the electrochemical cell in a manner that significantly adversely affects the performance of the electrochemical cell. Chemically compatible materials are chemically compatible with the electrolyte (e.g., zinc halide electrolyte, alkaline electrolyte) and the anode and cathode materials.

[0062] As used herein, "chemically inert" refers to a material that does not chemically react in any meaningful way with the electrolyte, anode, or cathode of an electrochemical cell.

[0063] II. Electrochemical Cells and Battery Stacks 1-15, in one aspect a static (non-flowable) bipolar zinc halide rechargeable electrochemical cell 100 and a battery stack 1000 of such cells are described.

[0064] A. Bipolar Electrochemical Cell The bipolar electrochemical cell 100 includes a bipolar electrode 102, a terminal assembly 104, and a zinc halide electrolyte.

[0065] 1. Bipolar electrodes The bipolar electrodes 102, 102' may include a bipolar electrode plate 208 having a front surface 212 and a rear surface 214. One of the surfaces is a cathode surface and the other is an anode surface. A cathode assembly 202 including a cathode substrate 224 is secured to a cathode surface, such as the front surface, of the bipolar electrode plate such that the cathode assembly is in electrical communication with at least that surface (e.g., the front surface) of the bipolar electrode plate 208. The bipolar electrodes 102 may be configured to electrodeposit zinc metal on the anode electrode surface (e.g., the rear surface of an adjacent bipolar electrode or the inner surface of an end plate of a terminal anode assembly) during charging of the electrochemical cell, and generate halide or mixed halide species that are reversibly sequestered within the cathode assembly. Conversely, the electrodes may oxidize the electrodeposited zinc metal to Zn during discharging of the electrochemical cell. 2+The catalyst is configured to generate a cation and reduce a halide or mixed halide species to the corresponding anion.

[0066] a.Bipolar electrode plate The bipolar electrode plate 208, 208' may include a front surface 212 (212') and a rear surface 214 (214'), for example, as shown in FIG. 8. In some embodiments, the front surface 212 is a cathode surface and the rear surface 214 is an anode surface (of the zinc anode 230). A cathode assembly is located on the cathode surface (e.g., the front surface 212) of the bipolar electrode plate 208. The bipolar electrode plate includes a conductive coating or film that is relatively inert to the zinc halide electrolyte used in the electrochemical cell or battery stack. In some embodiments, the conductive coating or film covers at least a portion of the bipolar electrode plate 208, for example, at least a portion of the front surface 212, at least a portion of the rear surface 214, or at least a portion of both surfaces.

[0067] In some embodiments, the bipolar electrode plate 208 comprises titanium, titanium oxide, TiC, TiN, graphite, or an electrically conductive plastic. In some embodiments, the bipolar electrode plate 208 comprises a titanium material. In some embodiments, the bipolar electrode plate 208 comprises a titanium material at least partially coated with a titanium carbide material. In some embodiments, the bipolar electrode plate 208 comprises a titanium material with carbon thermally diffused therein. In these embodiments, at least a portion of the front surface 212, at least a portion of the rear surface 214, or at least a portion of both surfaces is coated with a titanium carbide material or has carbon thermally diffused therein. In some embodiments, the bipolar electrode plate 208 comprises an electrically conductive carbon material, such as a graphite plate. In some embodiments, the bipolar electrode plate 208 comprises a graphite plate coated with a titanium carbide material. In these embodiments, at least a portion of the front surface 212, at least a portion of the rear surface 214, or at least a portion of either of these surfaces is coated with a titanium carbide material. In some embodiments, the bipolar electrode plate 208 comprises an electrically conductive plastic. Any suitable electrically conductive plastic may be used within the scope of what is described. Such electrically conductive plastic materials may include a base resin polymer with carbon black, graphite, fumed silica, or combinations thereof. For example, the electrically conductive plastics described in U.S. Patent No. 4,169,816, filed March 6, 1978, which is incorporated herein by reference, may be used within the scope of what is described herein.

[0068] The bipolar electrode plates described herein optionally include a recess 215 in the front surface 212 of the bipolar electrode plate. In some embodiments, the bipolar electrode plate includes a recess 215 in the front surface 212 of the bipolar electrode plate. In some of these embodiments, the periphery of the recess 215 is substantially defined by an outermost edge of the flange 220 of the cathode cage 216 of the cathode assembly 202 such that the cathode assembly at least partially fits within the recess 215 when the bipolar electrode is assembled. In other embodiments, the periphery of the recess is at least partially within the outermost edge of the flange 220 of the cathode cage 216 of the cathode assembly 202. In some of these embodiments, the recess may be defined by an outermost edge of the loaded carbon felt 224 that fits within the cathode cage 216 of the cathode assembly 202 such that the loaded carbon felt 224 fits at least partially within the recess 215 of the bipolar electrode plate when the bipolar electrode 102 is assembled. Also, in some alternative embodiments, the front surface 212 of the bipolar electrode plate is non-recessed such that the front surface is at least substantially flat.

[0069] The described bipolar electrode plates may optionally include one or more through holes at or near the perimeter 204 of the plate. With reference to Figures 2A-4B, in some embodiments, the bipolar electrode plates include one or more through holes 206, 210 at or near the perimeter 204 of the plate that may be useful for filling the electrochemical cell with liquid electrolyte or for aligning the electrode plate within a battery stack.

[0070] The bipolar electrode plate may be formed by stamping or other suitable methods. A portion of the front surface 212, a portion of the rear surface 214, or a portion of both surfaces may optionally receive a surface treatment (e.g., coating, etc.) to enhance the electrochemical properties of the cell or battery stack. The rear surface of the bipolar electrode plate may include an electrochemically active area associated with or defined by the formation of a zinc metal layer upon charging of the cell or battery stack. In some embodiments, the rear surface of the electrode plate may be sandblasted (e.g., sandblasted with SiC or garnet), textured, or otherwise treated in the electrochemically active area. In another embodiment, the front surface may also be sandblasted in the electrochemically active area associated with the area enclosed by the cathode assembly.

[0071] For example, in some embodiments, at least a portion of the rear surface, at least a portion of the front surface, or at least a portion of both surfaces are treated (e.g., sandblasted) to provide a roughened surface. In some cases, at least a portion of the rear surface of a bipolar electrode plate is treated (e.g., sandblasted) to provide a roughened surface. In some cases, the area of ​​the rear surface that is treated to provide a roughened surface is substantially defined by the perimeter of a cathode assembly secured to the front surface of the electrode plate.

[0072] In some embodiments, the electrochemical cell includes a semi-permeable barrier disposed between the anode and cathode sides. In some embodiments, the electrochemical cell does not include a semi-permeable barrier disposed between the anode and cathode sides.

[0073] b. Cathode Assembly The described electrochemical cells and battery stacks may include at least one cathode assembly 202. The cathode assembly 202 is located on the cathode side (e.g., front surface 212) of a bipolar electrode plate 208, where the cathode assembly 202 includes at least one cathode substrate 224. The cathode side is at least partially in contact with the cathode substrate 224. An adhesive, a glue, an electrically conductive bond, a tape, a mechanical cage, or a combination thereof electrically connects the cathode substrate 224 to the cathode side of the bipolar electrode plate 208. In some embodiments, the mechanical cage is a cathode cage.

[0074] ia cathode cage A mechanical cage, such as the cathode cage 216, includes a pocket 218 and a flange 220, which is disposed at the flange 220 on either the front surface 212, 212' of a bipolar electrode plate or the inner surface 316 of a terminal end plate. With reference to FIGS. 6A and 6B, a front view (FIG. 6A) and a side view (FIG. 6B) of the cathode cage 216 are shown. The cathode cage 216 includes an overall area defined by a length X1 and a width Y1, including the flange 220. To form the flanges, a flat metal sheet is placed in a forming machine that presses a flange on each of the four ends of the flat sheet. In some embodiments, the flat metal sheet includes a titanium or titanium carbide material. In some aspects, the cathode cage further includes slots at the corners of the cage. These slots may be formed by laser cutting. The cathode cage 216 includes a reduced area corresponding to the pocket 218, which is defined by a length X2 and a width Y2. Thus, X1 is greater than X2 and Y1 is greater than Y2. In the illustrated example, the flange 220 is bent flat against the pocket 218 to define the dimensions X1 / X2 and Y1 / Y2 and the depth of the pocket. In some embodiments, the area defined by X2 and Y2 represents an etched area where a plurality of holes 227 will be formed. The length X1 / X2 and width Y1 / Y2 may vary based on the operational requirements of the electrochemical cell 100 or battery stack 1000.

[0075] In some embodiments, the flange 220 includes a surface adjacent and in contact with the front surface 212 of the bipolar electrode plate, and the depth of the pocket 218 extends from the flange in a direction away from the front surface of the electrode plate. The cathode cage pocket 218 cooperates with the front surface of the electrode plate to form a chamber in which the loaded carbon felt 224 is located. In some of these embodiments, the cathode cage is attached to the front surface of the electrode plate at its flange by welding, use of adhesives, electrically conductive bonds, use of mechanical fasteners, or any combination thereof.

[0076] The cathode cage is formed from a metal, metal alloy, or plastic that is substantially inert to the electrolyte of the electrochemical cell or battery stack. In some embodiments, the cathode cage is stamped from a titanium material. In some embodiments, the cathode cage comprises titanium or titanium oxide. In some embodiments, the cathode cage comprises a titanium material coated with a titanium carbide material.

[0077] In some embodiments, the cathode cage pocket is chemically etched to form a plurality of spaced apart holes 227. In some embodiments, the holes are sized and spaced to form a hole pattern (e.g., a tailored hole pattern) that increases the uniformity of current and / or charge distributed across the cathode cage by compensating for deformation or bending of the cathode cage pocket that occurs during operation (e.g., charging or discharging) of the electrochemical cell.

[0078] FIG. 7A shows a front view of the cathode cage 216 illustrated by FIG. 6A including a plurality of holes 227 formed through the chemically etched surface of the pocket 218 by chemical etching. FIG. 7B shows a detailed view of the portion illustrated by FIG. 7A showing the distribution of the plurality of holes 227. The chemical etching process is a subtractive manufacturing process that removes solid material that is removed to form the plurality of holes 227. During the first step of the chemical etching process, the cathode cage 216 begins as a flat metal sheet that is cut using shear forces to achieve dimensions corresponding to X1 and Y1. The metal sheet may then be cleaned and coated with a dry film solder mask in a hot roll laminator and then cooled in the dark. A protective film may then be applied and the metal sheet exposed in a vacuum exposure unit. In some instances, the degree of exposure may be measured using a step indicator and is deemed exposed when the desired degree of exposure is achieved. The metal sheet is then passed through a developer to remove the protective film while a dissolving cleaner in the developer is applied to the metal sheet to remove unwanted unexposed resist. The metal sheets may then be placed in a furnace rack and fired at a predetermined temperature for a predetermined time. For example, the firing temperature may be about 250° F. for about 60 minutes. Following the firing cycle, each metal sheet is air cooled and a chemical etcher is programmed per the specifications of the desired etching area, e.g., the area defined by X2 and Y2, and the fired and cooled metal sheets are passed through the chemical etcher to remove unwanted material, thereby forming holes 227.

[0079] 7B, the plurality of holes 227 are spaced apart along the rows in a pattern. In some embodiments, the pattern is an alternating repeating pattern. In some embodiments, the pattern is selected to allow for uniform distribution of current throughout the cathode cage 216 in the presence of the cathode cage curving and deforming from a flat state during charging of the electrochemical cell or battery stack. Providing a hole pattern in the cathode cage in accordance with the present disclosure improves uniform distribution of charge and / or current, which results in more uniform electrodeposition of metallic zinc at the anode surface of the bipolar electrode plate (e.g., the rear surface 214 of the bipolar electrode plate, or the inner surface 318 of the end plate, or both surfaces) during a charging cycle. Similarly, the conversion of bromine to bromide anions at or near the cathode cage 216 may also be improved. In some aspects, the spacing of each hole of the plurality of holes 227 along a row in the x direction, the spacing of alternating rows in the y direction, and the diameter f of the holes may be selected to achieve a substantially uniform distribution of charge and / or current throughout the cathode cage 216 based on the amount of bending or deformation that occurs to the cathode cage and bipolar electrodes as the electrochemical cell or battery stack charges and discharges. In some embodiments, the distribution (e.g., spacing) of the x and y hole locations in the x and y directions, respectively, is based on the nominal hole area and the recommended web length of the cathode cage 216. The surface thickness of the pocket 218 may determine the dimensions of the nominal hole area and the recommended web length. In some examples, the centers of adjacent holes 227 along a row are spaced about 0.067 cm apart in the x direction, and every other row is spaced about 0.152 cm apart in the y direction. As described in more detail below, the cathode cage 216 and bipolar electrode plates 208, 208' or terminal end plate 302 curve a greater distance from flat in regions further from the periphery in their respective portions, resulting in a smaller spacing between the anode and cathode electrodes in the central region versus the outer regions closer to the periphery. In general, the smaller the spacing between the anode and cathode electrodes, the larger the calculated hole diameter at the corresponding x and y hole location.

[0080] ib adhesives, pressure sensitive adhesives, electrically conductive binders, and / or tapes In addition to or instead of the cathode cage, adhesives, glues, electrically conductive binders, and / or tapes may be applied to the bipolar electrode plate to hold the cathode substrate at least partially in contact with the bipolar electrode plate. The cathode cage, glues, glues, binders, or tapes are electrically conductive. In some embodiments, the bipolar electrodes and electrochemical cells are constructed without a cathode cage, with adhesives to attach the loading carbon felt to the cathode side of the bipolar electrode plate. The electrochemical cell does not include any graphite plate in electrical communication with the cathode side of the bipolar plate.

[0081] As discussed above, below, and throughout, adhesive may be used to attach the cathode substrate to the bipolar electrode plate. In some embodiments, a volume (e.g., 5 ml) of adhesive or glue is applied to the cathode surface of the bipolar electrode, the cathode substrate is placed on the glue, pressure (e.g., 3 psi, 5 psi, etc.) is applied onto the carbon substrate, and the glue or glue is then allowed to dry (e.g., 1 hour). The glue may then hold the cathode substrate onto the surface of the bipolar electrode plate. The cathode substrate may have a substantially rectangular shape and may be aligned approximately in the center of the substantially rectangular bipolar electrode plate. In some embodiments, tape may be used instead of or in addition to the adhesive or glue.

[0082] One exemplary adhesive or glue that can be used to hold the carbon felt in contact with the bipolar electrode plate is an adhesive or glue that includes a mixture of acetone, polyvinylidene fluoride, methyl methacrylate / n-butyl methacrylate copolymer, and graphite. In some embodiments, the adhesive includes about 50 wt.% to about 75 wt.% acetone, about 10 wt.% to about 20 wt.% polyvinylidene fluoride, about 5 wt.% to about 10 wt.% methyl methacrylate / n-butyl methacrylate copolymer, and about 10 wt.% to about 20 wt.% graphite. For example, the adhesive or glue can include acetone, Kynar 2750, Elvacite 4111, and Timrex KS6 graphite.

[0083] ii. Cathode substrate The cathode substrate 224 is in electrical communication with the cathode side of the bipolar electrode plate 208 and is attached to the bipolar electrode plate 208 using a layer of adhesive, a glue, an electrically conductive adhesive, tape, or a combination thereof. In some embodiments, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0084] In some embodiments, the cathode substrate comprises at least one carbonaceous material. Carbonaceous materials suitable for the electrochemical cells described herein may include any carbonaceous material capable of reversibly absorbing aqueous bromine species (e.g., aqueous bromine or aqueous bromide) (collectively 702) and that is substantially chemically inert in the presence of an electrolyte. In some embodiments, the carbonaceous material comprises carbon black or other furnace process carbon. Suitable carbon black materials include, but are not limited to, Cabot Vulcan® XC72R, Akzo-Nobel Ketjenblack EC600JD, and other matte black mixtures of electrically conductive furnace process carbon blacks. In some embodiments, the carbonaceous material may also include other components, including, but not limited to, a PTFE binder and deionized water. For example, the carbonaceous material has a moisture content of less than 50 wt.% (e.g., about 0.01 wt.% to about 30 wt.%) based on the weight of the carbonaceous material. In some embodiments, the carbon material comprises PTFE (eg, about 0.5 wt.% to about 5 wt.%, based on the weight of the carbon material).

[0085] In some embodiments, the carbon material may be in the form of one or more thin rectangular blocks. In some embodiments, the carbon material may include a single solid block. In other embodiments, the carbon material may include 1-5, 1-3, or 1-2 solid blocks of carbon black.

[0086] In some embodiments, the carbon material may include woven carbon fiber or non-woven carbon felt material.

[0087] In some embodiments, the cathode substrate comprises carbon felt. FIG. 9 shows front, side, and top perspective views of a loaded carbon felt for use as a cathode substrate according to one aspect of the device described herein. The carbon felt 224 is in electrical communication with the front surface 212, 212' of the bipolar electrode plate 208, 208' and is confined by the cathode cage 216, 216' and the front surface 212, 212' of the bipolar electrode plate. In some embodiments, the carbon felt is sized and shaped such that the loaded carbon felt can at least partially fit into the cathode cage. In some embodiments, the carbon felt is sized and shaped such that the loaded carbon felt can at least partially fit into the frame. In some embodiments, the carbon felt is oxidized, carbon treated, graphite treated, activated, or any combination thereof. In some embodiments, the carbon felt has a thickness of about 2 mm to about 10 mm. For example, the carbon felt can have a thickness of about 4 mm to about 8 mm, about 6 mm to about 10 mm, or about 2 mm to about 6 mm. Without limitation, other carbon felts suitable for use in the devices described herein are commercially available from Avcarb, Cera Materials, or SGL Group (e.g., Avcarb G150, Avcarb G150A, Avcarb G200, Avcarb G200A, Avcarb G250, Avcarb G250A, Avcarb Cl 50, Avcarb C200, Avcarb C250, Cera GFE-1, SGL GFA5, SGL GFA6, SGL KFD2.5, or SGL GFC4.6).

[0088] In some embodiments, the cathode substrate comprises compressed carbon powder, hi some embodiments, the carbon powder is activated carbon, carbon black, expanded graphite, graphite, or a combination of two or more thereof.

[0089] 2. Terminal Assembly The bipolar electrochemical cell or battery described herein further includes a terminal assembly. A suitable terminal assembly may be, for example, the terminal assembly described in PCT Publication WO 2019 / 108513, filed on November 27, 2018, which is incorporated herein by reference and may be used within the scope of what is described herein.

[0090] 10-11, the terminal assembly 104 may include a terminal 308, a conductive plate 304 with an electrically conductive perimeter 306, an electrically insulating tape member 310, and a terminal bipolar electrode plate 302. The conductive plate 304, the terminal bipolar electrode plate 302, and the electrically insulating tape member 310 have inner and outer surfaces that are at least substantially parallel to one another, where the outer surface of the conductive plate 304 is bonded to the terminal 308 and the inner surface of the conductive plate 304 is bonded to the outer surface of the terminal bipolar electrode plate 302, with the electrically insulating tape member 310 between the inner surface of the conductive plate 304 and the outer surface of the terminal bipolar electrode plate 302 such that the electrically insulating tape member 310 does not cover the entire inner surface of the conductive plate 304, and where the electrically conductive perimeter 306 allows for a bidirectional uniform flow of electrical current through the conductive plate 304 between the terminal 308 and the terminal bipolar electrode plate 302.

[0091] The insulating tape member 310 does not cover the entire surface of the conductive plate 304, allowing the electrically conductive perimeter 306 to be in electrical communication with the terminal bipolar electrode plate 302. In some embodiments, the dimensions of the insulating tape member 310 are smaller than the dimensions of the conductive plate 304. A terminal 308 of the bipolar electrochemical cell is connected for electrical communication with the conductive plate 304. In some embodiments, an outer surface of the conductive plate 304 is bonded to the terminal 308. In some embodiments, the terminal 308 comprises any electrically conductive material. In one embodiment, the terminal comprises brass (e.g., the terminal is a brass plug in electrical communication with or in contact with the outer perimeter of the terminal).

[0092] The terminal bipolar electrode plate 302 of the terminal assembly 104 has inner and outer surfaces that are at least substantially parallel to the inner and outer surfaces of the conductive flat plate 304 and the electrically insulating tape member 310. The terminal bipolar electrode plate 302 may include, but is not limited to, titanium material coated with titanium carbide material, perforated holes, a roughened inner surface, and the like. The electrically conductive perimeter 306 of the flat plate 304 with the electrically insulating tape member 310 is bonded to the bipolar electrode plate 302 such that the electrically conductive perimeter 306 is approximately centered on an electrochemically active area of ​​the terminal bipolar electrode plate 302. In some embodiments, the electrochemically active area corresponds to an area extending between the inner and outer surfaces of the terminal bipolar electrode plate 302 that is in chemical or electrical communication with an adjacent terminal bipolar electrode plate during a charge / discharge cycle of an electrochemical cell. In these embodiments, the electrochemically active area for a terminal bipolar electrode plate 302 associated with the cathode terminal of the battery corresponds to or is defined by the area surrounded by a cathode assembly disposed on the inner surface of the terminal bipolar electrode plate 302 (e.g., terminal cathode electrode plate). The electrochemically active area for a terminal bipolar electrode plate 302 associated with the anode terminal of the battery may correspond to the area on its inner surface (terminal anode assembly) opposite the cathode assembly disposed in front of the adjacent bipolar electrode plate and that forms a layer of zinc metal upon charging of the battery. In some embodiments, at least a portion of the surface (e.g., at least the chemically active area) of the terminal bipolar electrode plate 302 of the terminal anode assembly is roughened.

[0093] FIG. 11 is an exploded view of the terminal assembly of FIG. 10 showing the cathode carbon material 224, the adhesive layer 311, the terminal bipolar electrode plate 302, the electrically insulating tape member 310, the conductive plate 304, the electrically conductive perimeter 306, and the terminal 308.

[0094] In some embodiments, the electrically conductive perimeter 306 formed by the weld is centered within the electrochemically active area of ​​the terminal bipolar electrode plate 302. In some embodiments, the electrically conductive perimeter 306 is substantially rectangular, substantially circular, or substantially elliptical. In some embodiments, the electrically conductive perimeter 306 is substantially rectangular.

[0095] In some embodiments, the conductive plate 304 with the electrically insulating tape member 310 is centered within the electrochemically active area of ​​the terminal bipolar electrode plate 302 .

[0096] In some embodiments, a surface of the electrically insulating tape member is joined to a surface of the conductive plate by welding or an adhesive, hi some embodiments, the adhesive is electrically conductive.

[0097] The conductive plates described herein are larger than prior art current collectors, thus providing more contact points and better current density distribution, which reduces manufacturing costs.

[0098] In some embodiments, the terminal assembly is a terminal cathode assembly, where the terminal cathode assembly includes a terminal bipolar electrode plate 302 having an electrochemically active area, a conductive plate 304 with an electrically insulating tape member 310 disposed on a surface of the terminal bipolar electrode plate 302 and approximately in the center of the electrochemically active area, and a cathode assembly, such as any of the cathode assemblies described herein, disposed on an inner surface of the terminal bipolar electrode plate 302.

[0099] In some embodiments, the terminal assembly is a terminal anode assembly, where the terminal anode assembly includes a terminal bipolar electrode plate 302 having an electrochemically active area and a conductive flat plate 304 with an electrically insulating tape member 310 in the center of the electrochemically active area, and the terminal anode assembly does not have a cathode assembly.

[0100] In some embodiments, the electrically conductive periphery 306 of the conductive plate 304 with the electrically insulating tape member 310 is joined to the surface of the terminal bipolar electrode plate 302 by welding or adhesive. Non-limiting examples of suitable welding methods include spot welding, continuous welding, tungsten inert gas (TIG) welding, or resistance welding. In some examples, the adhesive is electrically conductive. Non-limiting examples of suitable electrically conductive adhesives include graphite filled adhesives (e.g., graphite filled epoxy, graphite filled silicone, graphite filled elastomer, or any combination thereof), nickel filled adhesives (e.g., nickel filled epoxy), silver filled adhesives (e.g., silver filled epoxy), copper filled adhesives (e.g., copper filled epoxy), any combination thereof, and the like.

[0101] In some embodiments, the conductive plate 304 with the electrically insulating tape member 310 is comprised of at least one of copper alloy, copper / titanium clad, aluminum, titanium, and electrically conductive ceramics.

[0102] In some embodiments, at least one of the conductive plate 304 with the electrically insulating tape member 310 or the terminal bipolar electrode plate 302 comprises titanium. In some embodiments, at least one of the conductive plate 304 with the electrically insulating tape member 310 or the terminal bipolar electrode plate 302 comprises a titanium material coated with a titanium carbide material.

[0103] In some embodiments, at least one inner surface of the conductive plate 304 with the electrically insulating tape member 310 comprises copper.

[0104] In some embodiments, at least one outer surface of the conductive plate 304 with the electrically insulating tape member 310 comprises at least one of copper, titanium, and an electrically conductive ceramic.

[0105] In some embodiments, the conductive plate 304 with the electrically insulating tape member 310 comprises a first metal and the terminal bipolar electrode plate 302 comprises a second metal.

[0106] In some embodiments, the electrically insulating tape member 310 may include any adhesive material that has electrically insulating properties. Non-limiting examples of electrically insulating tape member 310 include, for example, Kapton™, Mylar™, polyimide, polyethylene, nylon, Teflon, neoprene, or any other electrically insulating polymer.

[0107] 3. Zinc halide electrolyte In the electrochemical cells and battery stacks described, an aqueous electrolyte, i.e., a zinc halide electrolyte, is interposed between the inner surface of the terminal end plate, the cathode assembly, the front surface of the bipolar electrode, and the inner surface of the frame, if present. In these embodiments, bromide anions at the surface of the cathode cage of the cathode assembly exposed to the electrolyte are oxidized to bromine when the electrochemical cell or battery stack is charged. Conversely, bromine is reduced to bromide anions during discharge. The conversion of bromine to bromide anions 232 at or near the cathode assembly can be represented as follows: Br2+2e - →2Br - .

[0108] Described herein are aqueous electrolytes useful for flowable or non-flowable (i.e. static) rechargeable zinc halide electrochemical cells or battery stacks in which zinc bromide, zinc chloride, or any combination of the two present in the electrolyte act as the electrochemically active material.

[0109] Any suitable zinc halide electrolyte can be used within the scope described herein.For example, the electrolyte described in PCT International Publication No. 2016 / 057477, filed October 6, 2015, and U.S. Patent Application Publication No. 2017 / 0194666, filed March 29, 2016, both of which are incorporated herein by reference, can be used within the scope described herein.

[0110] One aspect of what is described herein contemplates an electrolyte for use in a secondary zinc bromide electrochemical cell comprising about 30 wt.% to about 40 wt.% ZnCl or ZnBr, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and one or more quaternary ammonium agents, where the electrolyte comprises about 0.5 wt.% to about 10 wt.% of the one or more quaternary ammonium agents.

[0111] In some embodiments, the electrolyte comprises about 4 wt.% to about 12 wt.% (e.g., about 6 wt.% to about 10 wt.%) potassium bromide (KBr). In some embodiments, the electrolyte comprises about 8 wt.% to about 12 wt.% potassium bromide (KBr).

[0112] In some embodiments, the electrolyte comprises about 4 wt.% to about 12 wt.% (e.g., about 6 wt.% to about 10 wt.%) potassium chloride (KCl). In some embodiments, the electrolyte comprises about 8 wt.% to about 14 wt.% potassium chloride (KCl). In some embodiments, the electrolyte comprises about 11 wt.% to about 14 wt.% potassium chloride (KCl).

[0113] In some embodiments, the aqueous electrolyte comprises about 25 wt.% to about 70 wt.% ZnBr2, about 5 wt.% to about 50 wt.% water, and about 0.05 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0114] In some embodiments, the aqueous electrolyte comprises about 25 wt.% to about 40 wt.% ZnBr2, about 25 wt.% to about 50 wt.% water, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and about 0.5 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0115] In some embodiments, the one or more quaternary ammonium agents are ammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, trimethylpropylammonium bromide, triethylmethylammonium chloride, trimethylpropylammonium chloride, butyltrimethylammonium chloride, trimethylethylammonium chloride, N-methyl-N-ethylmorpholinium bromide, N-methyl-N-ethylmorpholinium bromide (MEMBr), 1-ethyl-1-methylmorpholinium bromide, N-methyl-N-butylmorpholinium bromide, N-methyl-N-ethylpyrrolidinium bromide, N,N,N-triethyl-N-propylammonium bromide, N-ethyl-N-propylpyrrolidinium bromide, N-propyl-N-butylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, 1-methyl- The quaternary agent may be selected from the group consisting of 1-butylpyrrolidinium, N-ethyl-N-(2-chloroethyl)pyrrolidinium bromide, N-methyl-N-hexylpyrrolidinium bromide, N-methyl-N-pentylpyrrolidinium bromide, N-ethyl-N-pentylpyrrolidinium bromide, N-ethyl-N-butylpyrrolidinium bromide, trimethylene-bis(N-methylpyrrolidinium) dibromide, N-butyl-N-pentylpyrrolidinium bromide, N-methyl-N-propylpyrrolidinium bromide, N-propyl-N-pentylpyrrolidinium bromide, 1-ethyl-4-methylpyridinium bromide, 1-ethyl-2-methylpyridinium bromide, 1-butyl-3-methylpyridinium bromide, cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, cetyltriethylammonium bromide, and any combination thereof.

[0116] In some embodiments, the one or more quaternary ammonium agents comprise alkyl-substituted pyridinium chlorides, alkyl-substituted pyridinium bromides, alkyl-substituted morpholinium chlorides, alkyl-substituted morpholinium bromides, alkyl-substituted pyrrolidinium chlorides, alkyl-substituted pyrrolidinium bromides, or any combination thereof.

[0117] In some embodiments, the electrolyte is a glyme (e.g., monoglyme, diglyme, triglyme, tetraglyme, pentaglyme, hexaglyme, or any combination thereof), an ether (e.g., DME-PEG, dimethyl ether, or a combination thereof), an alcohol (e.g., methanol, ethanol, 1-propanol, isopropanol, 1-butanol, sec-butanol, isobutanol, tert-butanol, or any combination thereof), a glycol (e.g., ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, neopentyl glycol, hexalene glycol, tetraglyme, pentaglycol, tetra ... glycol), or any combination thereof), an additive (e.g., Sn, In, Ga, Al, Tl, Bi, Pb, Sb, Ag, Mn, Fe, or any combination thereof), an acid (e.g., acetic acid, nitric acid, citric acid, or any combination thereof), potassium dihydrogen citrate, a crown ether (e.g., 18-crown-6, 15-crown-5, or combinations thereof), citric acid monohydrate, or potassium dihydrogen citrate monohydrate.

[0118] In one embodiment, the electrolyte is zinc bromide, 27.42 wt.%; water, 44.34 wt.%; potassium bromide, 6.78 wt.%; potassium chloride, 9.83%; 2,5,8,11,14-pentaoxapentadecane, 2.58 wt.%; 4-ethyl-4-methylmorpholin-4-ium bromide, 1.03 wt.%; tetraethylammonium bromide, 2.03 wt.%; triethylmethylammonium chloride, 1.94 wt.%; methoxypolyethylene glycol MW2000, 1.29 wt.%. t.%; methoxypolyethylene glycol MW1000, 0.32 wt.%; 2,2-dimethyl-1,3-propanediol, 1.29 wt.%; 2-methylpropan-2-ol, 0.32 wt.%; hexadecyltrimethylammonium bromide, 0.06 wt.%; hydrobromic acid (to reach pH 3.6), 0.52 wt.%; 1,1-dioctadecyl-4,4'bipyridinium dibromide, 0.25 wt.%; tin chloride, 7 ppm; and indium chloride, 7 ppm.

[0119] In one embodiment, the electrolyte consists of zinc bromide, 35.41 wt.%; water, 38.84 wt.%; potassium bromide, 5.54 wt.%; potassium chloride, 11.09 wt.%; triethylmethylammonium chloride, 5.8 wt.%; polyethylene glycol dimethyl ether (MW2000), 1.26 wt.%; polyethylene glycol dimethyl ether (MW1000), 0.35 wt.%; 2,2-dimethylpropane-1,3-diol, 1 wt.%; trimethylsiloxy-terminated polydimethylsiloxane (MW1250), 0.2 wt.%; indium chloride, 7 ppm; and tin chloride, 7 ppm.

[0120] B. Battery Stack The battery stack includes a plurality of bipolar electrodes disposed at least partially within a zinc halide electrolyte and interposed between a cathode terminal assembly and an anode terminal assembly, the cathode terminal assembly, the anode terminal assembly, the zinc halide electrolyte, and the bipolar electrodes including any embodiment described herein.

[0121] 12 and 13, a battery stack 1000 includes at least one bipolar electrochemical cell and a two terminal electrochemical cell. In one embodiment, the battery stack includes 40 bipolar electrochemical cells in series and a two terminal electrochemical cell.

[0122] At least one bipolar electrochemical cell includes a bipolar electrode 102, a battery frame member 114, and a zinc halide electrolyte. The terminal electrochemical cell includes a bipolar electrode 102, a battery frame member 114, a terminal assembly 104, a terminal end plate 105, and a zinc halide electrolyte.

[0123] 1. Frame members In some embodiments, the battery includes a battery frame member 114 that is interposed between two adjacent bipolar electrodes or between a bipolar electrode 102 and a terminal assembly 104 (e.g., a terminal anode assembly or a terminal cathode assembly).

[0124] 14, the battery frame member 114 has an outer perimeter edge and an inner perimeter edge that defines a hollow interior region. In some embodiments, the battery frame member 114 is configured such that the hollow interior region is approximately centered about the center of an electrochemically active area of ​​a terminal bipolar electrode plate 302 received by the battery frame member 114 and / or the center of a cathode assembly disposed on the terminal bipolar electrode plate 302. In some embodiments, the outer perimeter of the battery frame member 114 defines the exterior surface of the battery.

[0125] In some embodiments, the battery frame member 114 includes a first side that faces and holds a first terminal bipolar electrode plate 302 and a second side disposed opposite the first side of the battery frame member 114 that faces and holds a second bipolar electrode plate. The second electrode plate is adjacent to and parallel to the first electrode plate in the battery. The first and second electrode plates and the terminal electrode plate may be configured to have substantially the same size and shape. In some embodiments, the battery frame member 114 contacts the anode bipolar electrode plate on one side and the cathode bipolar electrode plate of an adjacent bipolar cell on the other side.

[0126] In some embodiments, the battery frame member 114 includes a seal member 116 (FIG. 14) extending around an inner periphery. In some embodiments, the battery frame member 114 includes a first seal member 116 disposed along a first inner periphery. In some embodiments, the first seal member is an O-ring. In some embodiments, the first seal member 116 is a gasket. In some embodiments, each inner periphery is configured to receive a seal member 116 mounted thereon that forms a substantially leak-tight seal when the seal is compressed between a corresponding bipolar or terminal electrode plate and the battery frame member 114 when the electrochemical cell is assembled to provide a sealing interface between the bipolar electrode plate or end plate and the battery frame member 114. The seal members cooperate to retain electrolyte between opposing bipolar electrode plates and the battery frame member 114, or between the bipolar electrode plate, terminal electrode plate and the frame member 114.

[0127] In some embodiments, the battery frame member 114 includes a trough at the bottom of the battery frame member 114 to prevent voltage anomalies during cycling. In some embodiments, the trough includes a trough shelf 406 and a gap 407 below the trough shelf 406. In some embodiments, the cathode carbon material 224 rests on the trough shelf 406. It has been found that the presence of the trough shelf and the gap below the trough shelf prevents voltage anomalies during cycling. In some embodiments, there is no gap 407 below the trough shelf 406, and the trough shelf 406 extends to the bottom of the battery frame member 114. In some embodiments, the trough shelf 406 on which the cathode carbon material 224 rests can be 0.5-5 cm high, including the gap 407 below the trough shelf 406, and can be 3 mm to 10 mm wide along the entire width of the bottom of the battery frame member 114.

[0128] In some embodiments, the battery frame member includes a first frame member and a second frame member, hi some embodiments, the first frame member and the second frame member are stacked horizontally and oriented vertically, and a first outer edge of the first frame member is substantially coplanar with a second outer edge of the second frame member.

[0129] In some embodiments of the battery, each battery frame member 114 is plastic welded to an adjacent frame member 114 with a weld bead 405 around the perimeter of the battery frame member 114 .

[0130] In some embodiments, a liquid diversion system is present at the top of the cell frame member 114 directly below the vent 402 that allows gas to escape into the gas flow path 401. In some embodiments, the liquid diversion system includes a primary diverter mechanism 403 with two partial barriers 404 and multiple secondary barriers to ensure that liquid is always directed back into the hollow interior region within the cell frame member 114. In some embodiments, the primary diverter 403 consists of a horizontal plastic protrusion with end pieces pointing downward at an angle ranging from 30 to 60 degrees. In some embodiments, the secondary barriers ensure that minimal liquid reaches the primary diverter. One advantage of the liquid diversion system is that it improves battery quality by keeping the electrolyte within the frame member during shipping.

[0131] Each battery frame member 114 may be formed from flame retardant polypropylene fibers, high density polyethylene, polyphenylene oxide, or polyphenylene ether. Each battery frame member 114 may receive two adjacent bipolar electrode plates, or a bipolar electrode plate and a terminal electrode plate. Each battery frame member 114 may also contain an aqueous electrolyte solution (e.g., a zinc halide electrolyte or a zinc bromide electrolyte).

[0132] 15 is an enlarged side view of the bottom of a battery frame member 114 showing a trough ledge 406 and a cavity 407 below the trough ledge. In this embodiment, each frame member in the battery includes a trough ledge 406 and a cavity 407.

[0133] 2. Pressure plate In some embodiments, the electrochemical cell or battery stack includes a pair of pressure plates located at the ends of the electrochemical cell or battery stack. Suitable pressure plates may be used within the scope of those described herein, for example, pressure plates described in PCT Publication WO 2019 / 108513, filed November 27, 2018, which is incorporated herein by reference.

[0134] III. Bipolar Electrode Including a Cathodic Surface Having a Halogen Complexing Agent A. Cathode substrate with halogen complexing agent As discussed above, the optimal cathode surface for a zinc-bromine battery should exhibit rapid bromine redox rate, high bromine complex retention, low electrical resistance, and high chemical stability. However, current zinc-bromine batteries rely on physical trapping of bromine or polybromides in a porous cathode substrate, which is difficult when concentration and density gradients can cause bromine and polybromides to migrate away from the cathode and become unavailable during discharge. Polybromides tend to accumulate at the bottom of the cathode substrate, reducing the surface area of ​​the cathode substrate available during discharge. Part of the polybromide oil phase is completely lost from the cathode substrate, which means that it can contact the anode and increase the self-discharge rate.

[0135] The present inventors have unexpectedly found that bipolar electrodes having a cathode substrate loaded with the halogen complexing agent described herein can improve the spatial distribution of bromine retention and capacity at the cathode surface. A method is described herein for chemically binding bromine and polybromides to the cathode surface that fixes bromine and polybromides in one location. Without wishing to be bound by theory, it is hypothesized that the halogen complexing agent is chemically bound to the cathode substrate by utilizing oxygen functional groups on the cathode substrate. The halogen complexing agent can then be utilized to complex bromine and polybromides and keep these materials fixed / bound to the cathode substrate surface. This approach is advantageous in that (1) a wide range of chemical options are available for introducing the halogen complexing agent to be bound to the cathode substrate; (2) the halogen complexing agent functional groups cover only a portion of the cathode substrate so that the reactive sites on the cathode substrate are not compromised; (3) this approach is a convenient and cost-effective method for processing the majority of cathode substrates, including carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, and reticulated carbon; and (4) this approach can be easily scaled up to large-scale manufacturing and large electrodes for commercial applications.

[0136] One aspect of what is described herein is a method for producing a pharmaceutical composition comprising: a bipolar electrode plate having a cathode surface and an anode surface, the cathode surface being opposite the anode surface; a cathode substrate loaded with a halogen complexing agent, the cathode surface being at least partially in contact with the cathode substrate; The halogen complexing agent is represented by the formula (I): + (R A )(R B )(R C )(R D )X - The structure is During the ceremony, Q is N, P, or S; R A , R B , and R C are each independently hydrogen or an optionally substituted branched or unbranched C1-C 20 alkyl, aryl, or vinyl, or R A~C any two of these together with Q form a C3-C6 cyclic group which may contain one or more additional heteroatoms selected from N, P, and O; R D may be substituted, branched or unbranched, C1-C 20 alkyl, allyl, vinyl, or a C3-C6 cyclic group optionally containing one or more heteroatoms selected from N, P, and O, where R D has a terminal functional group, X - F - , Cl - , Br - , or I - and Here, the functional groups are -PO3H2, -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, During the ceremony, R E , R F , and R G are each independently OCH3, OCH2CH3, CH3, or Cl; R H and R I are each independently H or C1 to C 20 is alkyl, Y is a halide.

[0137] In one embodiment, R A , R B , R C , and R DEach group may be independently substituted with a halide, hydroxy, carboxylic acid, ether, amine, amide, or ammonium. A , R B , and R C Non-limiting examples of each of the groups include, for example, optionally substituted methyl, ethyl, propyl, butyl, pentyl, hexyl, dodecyl, octadecyl, ethenyl, 2-propenyl, ethynyl, 2-propynyl, pyridinium (C5H5N + -), piperidinium (CH 12 N + -), pyrrolidinium (C4H8N + -), or imidazolium (C3H3N(R)N + -) is included.

[0138] R D The group may be optionally substituted, branched or unbranched, C1-C 20 alkyl, allyl, vinyl, or a C3-C6 cyclic group optionally containing one or more heteroatoms selected from N, P, and O, where R D R has a terminal functional group. D Non-limiting examples of groups include, for example, optionally substituted methyl, ethyl, propyl, butyl, pentyl, hexyl, dodecyl, octadecyl, ethenyl, 2-propenyl, ethynyl, 2-propynyl, pyridinium (C5H5N + -), piperidinium (CH 12 N + -), pyrrolidinium (C4H8N + -), or imidazolium (C3H3N(R)N + In some embodiments, the terminal functional group is a phosphonic acid group, a silyl ether group, or a halogenated alkyl group.

[0139] The halogen complexing agent is introduced to the cathode substrate as a monomer. In some embodiments, the halogen complexing agent does not include a polymer. The halogen complexing agent forms a self-assembled monolayer or multilayer that coats the surface of the cathode substrate. In some embodiments, the cathode substrate is chemically bonded to the monomer of the halogen complexing agent. In some embodiments, the cathode substrate is chemically bonded to the polymer of the halogen complexing agent. The monolayer or multilayer film formed is so thin that it does not significantly increase the resistance of the cell, reduce the electrochemically active surface area of ​​the electrode, or prevent the flux transport of electrolyte components through the electrode, as other doping approaches can. Other approaches involving physical entrapment of the halogen complexing agent within the cathode substrate, for example by using a polymer or cross-linked polymer complexing agent, may prevent the transport of electrolyte components across the electrode or cover a large portion of the electrode surface, rendering it electrochemically inactive.

[0140] In some embodiments, the halogen complexing agent is a quaternary ammonium halide, a phosphonium halide, or a sulfonium halide. In one embodiment, the halogen complexing agent is a quaternary ammonium halide. It should be noted that the quaternary ammonium salts commonly used in electrolytes do not adhere strongly to the cathode substrate because no ionic or covalent interactions are formed between such quaternary ammonium salts and the cathode substrate. If the cathode is loaded with quaternary ammonium salts that are incapable of binding to the cathode substrate, the positive charge of the ammonium groups may cause them to migrate from the cathode toward the anode upon cycling of the battery. This would reduce the availability of bromine and polybromides in the cathode upon discharge. In contrast, if one of the side chains (i.e., R D By using halogen complexing agents described herein (e.g., including quaternary ammonium salts of formula (I)) that terminate in a functional group that can be covalently bonded to the surface of the cathode substrate, it is possible to coat the surface of the cathode substrate with a layer of halogen complexing agent that is strongly adherent and does not diffuse into the bulk electrolyte.

[0141] Non-limiting examples of halogen complexing agents include, for example, triethylammonium (12-dodecylphosphonate) bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium (12-dodecylphosphonate) chloride, pyridinium (12-dodecylphosphonate) bromide, N,N-dimethyl-N-octadecylammonium (12-dodecylphosphonate) bromide, 1-methyl-3-(dodecylphosphonate) imidazolium bromide, or 1-methyl-3-(hexylphosphonate) imidazolium bromide.

[0142] Figure 16 shows examples of self-assembled monolayers bound to an oxidized surface (e.g., a cathode substrate) using two different examples of halogen complexing agents described herein. In the example on the left, the halogen complexing agent is an R 2 -based phosphate buffer with an alkyl chain bearing a phosphonic acid terminal functional group at one end (attached to a quaternary ammonium halide at the other end). D The halogen complexing agent contains a silyl ether group. When such a halogen complexing agent is exposed to an oxidizing surface (e.g., a cathode substrate), the phosphonic acid combines with oxygen and they self-assemble to form a film one molecule thick, where the quaternary ammonium halide group (the selected group on the other end) coats the oxidizing surface (e.g., a cathode substrate). Similar results can be achieved when the halogen complexing agent is terminated with a silyl ether group instead of a phosphonic acid, as shown in the example on the right side of FIG. 16. Furthermore, the silyl ether group of the halogen complexing agent can polymerize to form Si-O-Si (siloxane) bonds during contacting the cathode substrate with a mixture containing a halogen complexing agent having a silyl ether group, depositing the mixture on the cathode substrate, or coating the cathode substrate with the mixture. These clusters of silane can be bonded to the oxidizing surface (e.g., a cathode substrate) in the formation of a monolayer or multilayer.

[0143] As discussed above, below, and throughout the application, in some embodiments, the cathode substrate is further treated, for example, the cathode substrate is oxidized, carbon treated, graphite treated, activated, or any combination thereof.

[0144] B. Method Another aspect of the present disclosure relates to a method for making a bipolar electrode, the method comprising the steps of: mixing a halogen complexing agent and a solvent to form a mixture; contacting a cathode substrate with the mixture to form a loaded cathode substrate by loading the mixture on the cathode substrate; and contacting at least a portion of the loaded cathode substrate with the cathode side of a bipolar electrode plate to form a bipolar electrode. The loaded cathode substrate is a cathode substrate chemically bonded with a halogen complexing agent. The halogen complexing agent is represented by the formula (I): Q + (R A )(R B )(R C )(R D )X - wherein the variables Q, R A , R B , R C , R D and X is as defined herein.

[0145] The halogen complexing agent, cathode substrate, and bipolar electrode plate are as described above and throughout the application. In some embodiments, the halogen complexing agent is triethylammonium (12-dodecylphosphonate) bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium (12-dodecylphosphonate) chloride, pyridinium (12-dodecylphosphonate) bromide, N,N-dimethyl-N-octadecylammonium (12-dodecylphosphonate) bromide, 1-methyl-3-(dodecylphosphonate) imidazolium bromide, or 1-methyl-3-(hexylphosphonate) imidazolium bromide.

[0146] The halogen complexing agent and the solvent are mixed to form a mixture. The solvent can be any suitable solvent that allows for dispersion of the halogen complexing agent, loading of the cathode substrate, and evaporation upon drying of the cathode substrate. In some embodiments, the solvent comprises water. In some embodiments, the solvent comprises a water-miscible solvent. In some embodiments, the solvent comprises water, an alcohol, or any combination thereof. In some embodiments, the alcohol is a primary, secondary, or tertiary alkyl alcohol. Non-limiting examples of solvents include, for example, water, methanol, ethanol, propanol, isopropyl alcohol, acetone, dimethylformamide, acetonitrile, dimethylsulfoxide, or combinations thereof. The concentration of the halogen complexing agent in the mixture is about 0.01 wt.% to about 1 wt.%, and the concentration of the solvent in the mixture is about 99 wt.% to about 99.99 wt.%.

[0147] The mixture comprising the halogen complexing agent and the solvent is contacted with the cathode substrate to form a loaded cathode substrate, in which the mixture is loaded onto the cathode substrate. The loaded cathode substrate is one in which the halogen complexing agent is chemically bonded to the cathode substrate. The halogen complexing agent can be present within, on, or both within and on the cathode substrate. The mixture comprising the halogen complexing agent and the solvent is applied to, contacted with, deposited on, or loaded onto the cathode substrate to produce the loaded cathode substrate. In some embodiments, the mixture is sprayed onto the cathode substrate, and in other embodiments, the cathode substrate is dip coated into the mixture. In some embodiments, the cathode substrate is immersed in the mixture comprising the halogen complexing agent and the solvent.

[0148] In some embodiments, the method further comprises drying the loaded cathode substrate. Drying may be performed to evaporate the solvent from the mixture. Drying may be performed under vacuum or in a ventilated environment such as a laboratory hood. A fast-evaporating solvent (e.g., acetone) may be selected to reduce drying time. In some embodiments, the method further comprises sonicating the mixture before and / or during contacting the cathode substrate with the mixture. In some embodiments, the cathode substrate is immersed in the mixture. For example, the cathode substrate is immersed and kept submerged in the mixture for about 15 seconds. In some embodiments, the mixture is stirred or agitated before and / or during contacting the cathode substrate with the mixture.

[0149] In some embodiments, the method further comprises sonicating the mixture of halogen complexing agent and solvent prior to, during, or both before and during contacting the cathode substrate with the mixture.

[0150] In some embodiments, the method further comprises additional treatment of the cathode substrate. The treatment may comprise one or more of oxidation, carbon treatment, activation, or graphite treatment methods. The oxidation or activation treatment modifies the cathode substrate to enhance its ability to bond with the halogen complexing agent. For example, oxidation or activation of the surface of the cathode substrate increases the surface concentration of oxygen, allowing for the formation of stronger bonds between the surface of the cathode substrate and the halogen complexing agent. The carbon or graphite treatment enhances the chemical stability and electrical conductivity of the cathode substrate, which improves the performance and life of the battery in which it is used.

[0151] In some embodiments, the additional treatment step is performed prior to, during, or both prior to and during contacting the cathode substrate with the mixture of halogen complexing agent and solvent. In some embodiments, the additional treatment step is performed prior to contacting the cathode substrate with the mixture of halogen complexing agent and solvent.

[0152] The additional treatment steps of oxidation, activation, carbon treatment, and / or graphite treatment can be performed in any order. The oxidation and activation process can involve treating the cathode substrate with oxygen or air environment. The oxidation process can include chemical, electrochemical, and thermal techniques, all of which are well known to those skilled in the art. The carbon and graphite treatment process can involve one or more of a wide range of coating processes to provide functionality. For example, dip, slot die coating (including multilayers), spray, comma bar, reverse roll, and Mayer rod processes. Processing equipment including slitters, calendars, sheeters, and hot presses and die cutters can also be used. In some embodiments, the treatment is performed at high temperatures, for example, above about 1000°C or up to about 3000°C.

[0153] Carbon and / or graphite treatments may also include chemical vapor deposition (CVD) of carbon or graphite. A typical CVD process deposits amorphous pyrolytic carbon (PC) onto a carbon substrate such as carbon fabric, paper, tow, etc. Substantially uniform layers may be applied with thicknesses ranging from nanometers to micrometers.

[0154] In some embodiments, the cathode substrate is pretreated with a strong base (such as KOH) prior to contacting the cathode substrate with the mixture of halogen complexing agent and solvent.

[0155] The cathode substrate is as described above and throughout the application, hi some embodiments, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0156] In some embodiments, the cathode substrate comprises carbon felt. In some embodiments, the carbon felt is oxidized, carbon-treated, graphite-treated, activated, or any combination thereof. Fabric and fabric composite structures can be engineered to create carbon felt suitable for use in electrochemical applications. In some embodiments, the carbon felt is formed from precursor materials including either polyacrylonitrile (PAN), rayon, or pitch. In some embodiments, the carbon felt is a directly activated nonwoven fiber with a high surface area. The carbon felt can have characteristics such as high adsorption capacity, fast adsorption rate, heat resistance, acid resistance, alkali resistance, etc.

[0157] In some embodiments, the carbon felt is loaded with a halogen complexing agent at a concentration of about 0.1 grams to about 500 grams per kilogram of carbon felt. For example, the carbon felt is loaded with a halogen complexing agent at a concentration of about 1 gram to about 100 grams per kilogram of carbon felt.

[0158] At least a portion of the loaded cathode substrate may be incorporated into a bipolar electrode, which may correspondingly be incorporated into the electrochemical cells and battery stacks described herein. To incorporate the loaded cathode substrate into a bipolar electrode, the loaded cathode substrate or at least a portion of the loaded cathode substrate is contacted to the cathode surface of a bipolar electrode plate to form a bipolar electrode.

[0159] The bipolar electrode plate is as described above and throughout the application. In some embodiments, the bipolar electrode plate comprises a titanium material. The titanium material may be at least partially coated with titanium carbide. In some embodiments, the bipolar electrode plate comprises titanium, TiC, TiN, graphite, or an electrically conductive plastic.

[0160] In some embodiments, an adhesive or glue can be used to bond the loaded cathode substrate to the cathode side of the bipolar electrode plate. The adhesive or glue is electrically conductive. In some embodiments, at least a portion of the cathode surface is coated with an adhesive or glue, the loaded cathode substrate is placed on top of the glue, pressure (e.g., 3 psi, 5 psi, etc.) is applied to the top of the loaded cathode substrate, and then the adhesive or glue is cured or dried (e.g., for 1 hour).

[0161] In another aspect, a cathode cage holds a loaded cathode substrate in contact with the cathode side of the bipolar electrode plate. Suitable cathode cage configurations for holding a loaded cathode substrate in contact with the bipolar electrode plate are as described above and throughout the application.

[0162] The loaded cathode substrate may be attached to the bipolar electrode plate using either an adhesive, a pressure sensitive adhesive, an electrically conductive binder, a tape, or a cathode cage, or a combination thereof. Thus, it is possible to have a bipolar electrode (and corresponding electrochemical cell) without a cathode cage, where contact is maintained using an adhesive, a pressure sensitive adhesive, an electrically conductive binder, or a tape. Similarly, it is possible to have a bipolar electrode (and corresponding electrochemical cell) without an adhesive, a pressure sensitive adhesive, an electrically conductive binder, or a tape, where contact is maintained using a cathode cage.

[0163] Another aspect of the present disclosure is a method for producing a method for manufacturing a semiconductor device comprising the steps of: a bipolar electrode plate including a cathode surface and an anode surface, the cathode surface being opposite the anode surface; and a cathode substrate loaded with a halogen complexing agent, the cathode surface being at least partially in contact with the cathode substrate; A bipolar electrode including: Aqueous zinc halide electrolyte and In an electrochemical cell comprising: + (R A )(R B )(R C )(R D )X - wherein the variables Q, R A , R B , R C , R D and X are as defined herein. As discussed above, the bipolar electrodes described herein can be correspondingly incorporated into the electrochemical cells described herein by stacking the electrodes using frame members as spacers and terminating the stack with terminal assemblies on both ends.

[0164] Yet another aspect of the present disclosure is a method for producing a method for manufacturing a semiconductor device comprising the steps of: A pair of terminal assemblies; at least one bipolar electrode interposed between the pair of terminal assemblies; A battery stack comprising: The bipolar electrodes are A bipolar electrode plate; a cathode substrate loaded with a halogen complexing agent; an aqueous zinc halide electrolyte in contact with the bipolar electrode plates and the cathode substrate; Including, For the battery stack, the halogen complexing agent is represented by the formula (I): Q + (R A )(R B )(R C )(R D )X - wherein the variables Q, R A , R B , R C , R D and X are as defined herein. As discussed above, the bipolar electrodes described herein can be correspondingly incorporated into the electrochemical cells described herein, which in turn can be correspondingly incorporated into the battery stacks described herein by stacking the electrodes using frame members as spacers and terminating the stack with terminal assemblies on both ends.

[0165] In some embodiments, the self-discharge rate of the battery stacks described herein is about 29% to about 34% lower in a single cycle compared to an equivalent battery stack that does not include a halogen complexing agent. EXAMPLES

[0166] IV. Working Examples Example 1: Preparation of carbon felt substrate loaded with silane-based halogen complexing agent A solution containing trimethyl{[3-(trimethoxysilyl)propyl]}ammonium chloride (13 mM) in 1:1 (v / v) methanol and water was prepared. Three identical 6 mm thick dry PAN fiber-based carbon felts, previously modified by carbon treatment, activation, and graphite treatment methods, were dipped into the mixture and submerged for approximately 15 seconds. The felts were removed and excess mixture poured off. Each felt was placed on a drying rack and allowed to dry in a fume hood for 72 hours. The felts were then placed in a 60°C oven for 1 hour.

[0167] Example 2: Preparation of carbon felt substrates loaded with phosphonate-based halogen complexing agents A solution of triethylammonium bromide (12-dodecylphosphonate) (0.231 mM) in ethanol was prepared. Three pieces of the same 6 mm thick dry PAN fiber-based carbon felt, previously modified by carbon treatment, activation and graphite treatment methods, were dipped into the mixture and submerged for approximately 15 seconds. The felts were removed and excess mixture poured off. Each felt was placed on a drying rack and allowed to dry in a fume hood for 24 hours. The felts were then placed in a 60°C oven for 1 hour.

[0168] Example 3: Preparation of test cells Test cells were assembled using titanium carbide coated titanium metal current collectors formed into plates. The anode and cathode plates were arranged in a parallel configuration separated by a 12 mm thick high density polyethylene frame containing a recessed seal ring that sealed the cell by compressing the components between two opposing steel pressure plates. Prior to cell assembly, the halogen complexing agent loaded carbon felt described above or an untreated control carbon felt was attached to the cathode titanium current collector using 13 ml of an electrically conductive acetone based adhesive. The assembled cell was filled with an electrolyte composed primarily of zinc bromide and water, with small amounts of potassium halide salts and tetraalkylammonium bromide salts.

[0169] Example 4: Discharge capacity of test cells The test cells were cycled using an Arbin Instruments battery cycler. The cells were charged to a capacity of 13 Ah at a constant power of 4 W. The charge voltage limit was 2.4 V. The cells were discharged at a constant power of 4 W until the voltage reached 1.1 V. Figure 17 shows the average discharge capacity versus cycle index for three cell populations prepared in triplicate containing either untreated control carbon felt (untreated) or carbon felt loaded with trimethyl{[3-(trimethoxysilyl)propyl]}ammonium chloride (silane) or triethylammonium (12-dodecylphosphonate) bromide (phosphonate). The discharge capacity of the cells containing the treated carbon felt was higher than that of the control carbon felt, suggesting that the carbon felt treatment increases the availability of charged material.

[0170] Example 5: Testing the self-discharge rate of test cells To test the self-discharge rate of test cells with different populations, the rest period from the end of the charging step (top-of-charge) to the beginning of discharge was varied between 0.08 and 4 hours per cycle. The self-discharge rate is defined as the rate of capacity loss as a function of the top-of-charge rest period. Table 1 shows the reduction in the self-discharge rate of carbon felt loaded with trimethyl{[3-(trimethoxysilyl)propyl]}ammonium chloride (silane) or triethylammonium (12-dodecylphosphonate) bromide (phosphonate) compared to a control population containing untreated carbon felt. The reduction in the self-discharge rate suggests that the carbon felt treatment reduces the crossover of bromine from the cathode to the anode (bromine can react with zinc) and reduces the discharge capacity.

[0171] [Table 1]

[0172] In the first aspect, a bipolar electrode plate having a cathode surface and an anode surface, the cathode surface being opposite the anode surface; a cathode substrate loaded with a halogen complexing agent, the cathode surface being at least partially in contact with the cathode substrate; A bipolar electrode comprising: The halogen complexing agent is represented by the formula (I): Q + (R A )(R B )(R C )(R D )X - wherein Q is N, P, or S; R A , R B , and R C are each independently hydrogen or an optionally substituted branched or unbranched C1-C 20 alkyl, aryl, or vinyl, or R A~C any two of these together with Q form a C3-C6 cyclic group which may contain one or more additional heteroatoms selected from N, P, and O; R D may be substituted, branched or unbranched, C1-C 20 alkyl, allyl, vinyl, or a C3-C6 cyclic group optionally containing one or more heteroatoms selected from N, P, and O, where R D has a terminal functional group; and X - F - , Cl - , Br - , or I - where the functional groups are -PO3H2, -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, wherein R E , R F , and R G are each independently OCH3, OCH2CH3, CH3, or Cl; R H and R I are each independently H or C1 to C 20 alkyl and Y is a halide; A bipolar electrode is described.

[0173] In the first aspect above, each optional substituent is independently a halide, hydroxy, carboxylic acid, ether, amine, amide, or ammonium.

[0174] In any of the first aspects above, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0175] In any of the first aspects above, the cathode substrate comprises carbon felt.

[0176] In any of the first aspects above, the cathode substrate comprises compressed carbon powder.

[0177] In any of the first aspects above, the carbon powder is activated carbon, carbon black, expanded graphite, graphite, or a combination of two or more thereof.

[0178] In any of the first aspects above, the cathode surface is at least partially attached to the cathode substrate using an adhesive, an electrically conductive binder, a tape, a mechanical cage, or a combination thereof.

[0179] In any of the first aspects above, the cathode substrate is oxidized, carbon-treated, graphite-treated, activated, or any combination thereof.

[0180] In either of the first aspects above, the loaded cathode substrate is chemically bonded to a halogen complexing agent.

[0181] In either of the first aspects above, the cathode substrate is chemically bonded to a monomer of a halogen complexing agent.

[0182] In either of the first aspects above, the cathode substrate is chemically bonded to a polymer of a halogen complexing agent.

[0183] In any of the first aspects above, the halogen complexing agent is triethylammonium 12-dodecylphosphonate bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium 12-dodecylphosphonate chloride, pyridinium 12-dodecylphosphonate bromide, N,N-dimethyl-N-octadecylammonium 12-dodecylphosphonate bromide, 1-methyl-3-(dodecylphosphonate)imidazolium bromide, or 1-methyl-3-(hexylphosphonate)imidazolium bromide.

[0184] In any of the first aspects above, the bipolar electrode plates include a titanium material.

[0185] In either of the first aspects above, the titanium material is at least partially coated with titanium carbide.

[0186] In any of the first aspects above, the bipolar electrode plates include titanium, TiC, TiN, graphite, or an electrically conductive plastic.

[0187] In a second aspect, a method for producing a bipolar electrode is described that includes the steps of: combining a halogen complexing agent and a solvent to form a mixture; contacting a cathode substrate with the mixture to form a loaded cathode substrate, where the cathode substrate is loaded with the mixture; and contacting at least a portion of the loaded cathode substrate with a cathode side of a bipolar electrode plate to form a bipolar electrode. The halogen complexing agent is represented by the formula (I):Q + (R A )(R B )(R C )(R D )X -where Q is N, P, or S; R A , R B , and R C each independently represents hydrogen or an optionally substituted branched or unbranched C1-C 20 alkyl, aryl, or vinyl, or R A~C Any two of R together with Q form a C3-C6 cyclic group which may contain one or more additional heteroatoms selected from N, P, and O; D is an optionally substituted, branched or unbranched, C1-C 20 alkyl, allyl, vinyl, or a C3-C6 cyclic group optionally containing one or more heteroatoms selected from N, P, and O, where R D has a terminal functional group; and X - is F - , Cl - , Br - , or I - where the functional groups are -PO3H2, -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, wherein R E , R F , and R G are each independently OCH3, OCH2CH3, CH3, or Cl; R H and R I are each independently H or C1-C 20 is alkyl and Y is a halide.

[0188] In the above second aspect, the method further comprises the step of drying the loaded cathode substrate.

[0189] In either of the second aspects above, the method further comprises sonicating the mixture prior to, during, or both before and during contacting the cathode substrate with the mixture.

[0190] In either of the second aspects above, the solvent is water, an alcohol, or a combination thereof.

[0191] In either of the second aspects above, the cathode substrate is immersed in the mixture.

[0192] In any of the above second aspects, the method further comprises treating the cathode substrate, the treatment being selected from oxidation, carbon treatment, activation, graphite treatment, or any combination thereof.

[0193] In either of the second aspects above, the oxidation, carbon treatment, activation, graphite treatment, or any combination thereof is performed prior to contacting the cathode substrate with the mixture.

[0194] In either of the second aspects above, the halogen complexing agent in the mixture is a monomer.

[0195] In either of the above second aspects, the loaded cathode substrate is a cathode substrate chemically bonded with a halogen complexing agent.

[0196] In either of the second aspects above, the cathode substrate is chemically bonded to a monomer of a halogen complexing agent.

[0197] In either of the second aspects above, the cathode substrate is chemically bonded to a polymer of a halogen complexing agent.

[0198] In the third aspect, a bipolar electrode plate including a cathode surface and an anode surface, the cathode surface being opposite the anode surface; and a cathode substrate loaded with a halogen complexing agent, the cathode surface being at least partially in contact with the cathode substrate; A bipolar electrode including: Aqueous zinc halide electrolyte and The electrochemical cell includes a halogen complexing agent having the formula (I): + (RA )(R B )(R C )(R D )X - where Q is N, P, or S; R A , R B , and R C each independently represents hydrogen or an optionally substituted branched or unbranched C1-C 20 alkyl, aryl, or vinyl, or R A~C Any two of R together with Q form a C3-C6 cyclic group which may contain one or more additional heteroatoms selected from N, P, and O; D is an optionally substituted, branched or unbranched, C1-C 20 alkyl, allyl, vinyl, or a C3-C6 cyclic group optionally containing one or more heteroatoms selected from N, P, and O, where R D has a terminal functional group; and X - is F - , Cl - , Br - , or I - where the functional groups are -PO3H2, -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, wherein R E , R F , and R G are each independently OCH3, OCH2CH3, CH3, or Cl; R H and R I are each independently H or C1-C 20 is alkyl and Y is a halide.

[0199] In the third aspect above, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0200] In any of the third aspects above, the halogen complexing agent is triethylammonium 12-dodecylphosphonate bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium 12-dodecylphosphonate chloride, pyridinium 12-dodecylphosphonate bromide, N,N-dimethyl-N-octadecylammonium 12-dodecylphosphonate bromide, 1-methyl-3-(dodecylphosphonate)imidazolium bromide, or 1-methyl-3-(hexylphosphonate)imidazolium bromide.

[0201] In any of the third aspects above, the bipolar electrode plates include titanium, TiC, TiN, graphite, or an electrically conductive plastic.

[0202] In any of the third aspects above, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 70 wt.% ZnBr2, about 5 wt.% to about 50 wt.% water, and about 0.05 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0203] In any of the third aspects above, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 40 wt.% ZnBr2, about 25 wt.% to about 50 wt.% water, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and about 0.5 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0204] In any of the third aspects above, the one or more quaternary ammonium agents are ammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, trimethylpropylammonium bromide, triethylmethylammonium chloride, trimethylpropylammonium chloride, butyltrimethylammonium chloride, trimethylethylammonium chloride, N-methyl-N-ethylmorpholinium bromide, N-methyl-N-ethylmorpholinium bromide (MEMBr), 1-ethyl-1-methylmorpholinium bromide, N-methyl-N-butylmorpholinium bromide, N-methyl-N-ethylpyrrolidinium bromide, N,N,N-triethyl-N-propylammonium bromide, N-ethyl-N-propylpyrrolidinium bromide, N-propyl-N-butylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, 1-methyl-N-ethylpyrrolidinium bromide, N ... and any combination thereof.

[0205] In any of the above third aspects, the one or more quaternary ammonium agents comprise alkyl-substituted pyridinium chlorides, alkyl-substituted pyridinium bromides, alkyl-substituted morpholinium chlorides, alkyl-substituted morpholinium bromides, alkyl-substituted pyrrolidinium chlorides, alkyl-substituted pyrrolidinium bromides, or any combination thereof.

[0206] In the fourth aspect, A pair of terminal assemblies; at least one bipolar electrode interposed between the pair of terminal assemblies; A battery stack comprising: The bipolar electrodes are A bipolar electrode plate; a cathode substrate loaded with a halogen complexing agent; an aqueous zinc halide electrolyte in contact with the bipolar electrode plates and the cathode substrate; Including, A battery stack is described. The halogen complexing agent is represented by the formula (I): Q + (R A )(R B )(R C )(R D )X - where Q is N, P, or S; R A , R B , and R C each independently represents hydrogen or an optionally substituted branched or unbranched C1-C 20 alkyl, aryl, or vinyl, or R A~C Any two of R together with Q form a C3-C6 cyclic group which may contain one or more additional heteroatoms selected from N, P, and O; D is an optionally substituted, branched or unbranched, C1-C 20 alkyl, allyl, vinyl, or a C3-C6 cyclic group optionally containing one or more heteroatoms selected from N, P, and O, where R D has a terminal functional group; and X - is F - , Cl - , Br - , or I - where the functional groups are -PO3H2, -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, wherein R E , R F , and R Gare each independently OCH3, OCH2CH3, Cl, or CH3; R H and R I are each independently H or C1-C 20 is alkyl and Y is a halide.

[0207] In the above fourth aspect, the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon.

[0208] In any of the fourth aspects above, the halogen complexing agent is triethylammonium 12-dodecylphosphonate bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium 12-dodecylphosphonate chloride, pyridinium 12-dodecylphosphonate bromide, N,N-dimethyl-N-octadecylammonium 12-dodecylphosphonate bromide, 1-methyl-3-(dodecylphosphonate)imidazolium bromide, or 1-methyl-3-(hexylphosphonate)imidazolium bromide.

[0209] In any of the above fourth aspects, the bipolar electrode plates include titanium, TiC, TiN, graphite, or an electrically conductive plastic.

[0210] In any of the above fourth aspects, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 70 wt.% ZnBr2, about 5 wt.% to about 50 wt.% water, and about 0.05 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0211] In any of the above fourth aspects, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 40 wt.% ZnBr2, about 25 wt.% to about 50 wt.% water, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and about 0.5 wt.% to about 10 wt.% of one or more quaternary ammonium agents.

[0212] In any of the fourth aspects above, the one or more quaternary ammonium agents are ammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, trimethylpropylammonium bromide, triethylmethylammonium chloride, trimethylpropylammonium chloride, butyltrimethylammonium chloride, trimethylethylammonium chloride, N-methyl-N-ethylmorpholinium bromide, N-methyl-N-ethylmorpholinium bromide (MEMBr), 1-ethyl-1-methylmorpholinium bromide, N-methyl-N-butylmorpholinium bromide, N-methyl-N-ethylpyrrolidinium bromide, N,N,N-triethyl-N-propylammonium bromide, N-ethyl-N-propylpyrrolidinium bromide, N-propyl-N-butylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, 1-methyl-N-ethylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, N-methyl-N-ethyl ... and any combination thereof.

[0213] In any of the above fourth aspects, the one or more quaternary ammonium agents comprise alkyl-substituted pyridinium chlorides, alkyl-substituted pyridinium bromides, alkyl-substituted morpholinium chlorides, alkyl-substituted morpholinium bromides, alkyl-substituted pyrrolidinium chlorides, alkyl-substituted pyrrolidinium bromides, or any combination thereof.

[0214] In any of the above fourth aspects, the self-discharge rate of the battery stack is about 29% to about 34% lower in a single cycle compared to an equivalent battery stack that does not include the halogen complexing agent.

[0215] From the above and with reference to the various drawings, a person skilled in the art will recognize that certain modifications can be made to the present disclosure without departing from the scope of the present disclosure. Although some aspects of the disclosure are shown in the drawings, it is not intended that the disclosure be limited thereto, but rather that the disclosure be as broad as the art permits and the specification be read in the same manner. Therefore, the above description should not be interpreted as limiting, but merely as exemplification of certain aspects. A person skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

Claims

1. a bipolar electrode plate having a cathode surface and an anode surface, the cathode surface being opposite the anode surface; a cathode substrate loaded with a halogen complexing agent, the cathode surface being at least partially in contact with the cathode substrate; A bipolar electrode comprising: The halogen complexing agent is represented by formula (I): Q + (R A )(R B )(R C )(R D )X - The structure is During the ceremony, Q is N, P, or S; R A , R B , and R C are each independently hydrogen or unsubstituted or substituted, branched or unbranched C 1 ~C 20 alkyl, aryl, or vinyl, or R A～C Any two of the groups may, together with Q, contain one or more additional heteroatoms selected from N, P, and O. 3 ~C 6 Forming a heterocyclic group, R D is unsubstituted or substituted, branched or unbranched, C 1 ~C 20 C, which may contain one or more heteroatoms selected from alkyl, aryl, vinyl, or N, P, and O; 3 ~C 6 is a cyclic group, where R D further comprises a terminal functional group, and X is F, Cl, Br, or I; Here, R D The terminal functional group is -PO 3 H 2 , -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, During the ceremony, R E , R F , and R G Each is independent, OCH 3 , O.C.H. 2 CH 3 , C.H. 3 or Cl, R H and R I are each independently H or C 1 ~C 20 alkyl, and Y is a halide; Bipolar electrodes.

2. R A～D 2. The bipolar electrode of claim 1, wherein the substituents for are each independently one of a halide, hydroxy, carboxylic acid, ether, amine, amide, or ammonium.

3. the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon; Optionally, the cathode substrate comprises carbon felt or compressed carbon powder; Optionally, the carbon powder is activated carbon, carbon black, expanded graphite, graphite, or a combination of two or more thereof; 10. The bipolar electrode of claim 1.

4. the cathode surface in contact with the cathode substrate is connected to the cathode substrate using an adhesive, an electrically conductive binder, a tape, a mechanical cage, or a combination thereof; and / or the cathode substrate is oxidized, carbonized, graphitized, activated, or any combination thereof; and / or a cathode substrate loaded with a halogen complexing agent, the halogen complexing agent being chemically bonded thereto, and optionally the cathode substrate being chemically bonded to a monomer or polymer of the halogen complexing agent; The bipolar electrode of any one of claims 1 to 3.

5. The bipolar electrode according to any one of claims 1 to 4, wherein the halogen complexing agent is triethylammonium (12-dodecylphosphonic acid) bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium (12-dodecylphosphonic acid) chloride, pyridinium (12-dodecylphosphonic acid) bromide, N,N-dimethyl-N-octadecylammonium (12-dodecylphosphonic acid) bromide, 1-methyl-3-(dodecylphosphonic acid) imidazolium bromide, or 1-methyl-3-(hexylphosphonic acid) imidazolium bromide.

6. 6. The bipolar electrode of any one of claims 1 to 5, wherein the bipolar electrode plate comprises a titanium material, optionally the titanium material being at least partially coated with titanium carbide.

7. 6. The bipolar electrode of any one of claims 1 to 5, wherein the bipolar electrode plates comprise titanium, TiC, TiN, graphite, or an electrically conductive plastic.

8. A method for producing the bipolar electrode of claim 1, comprising the steps of: combining a halogen complexing agent and a solvent to form a mixture; contacting a cathode substrate with the mixture to form a loaded cathode substrate having the mixture loaded thereon; and contacting at least a portion of the loaded cathode substrate with the cathode side of the bipolar electrode plate to form a bipolar electrode. Including, The halogen complexing agent is represented by formula (I): Q + (R A )(R B )(R C )(R D )X - The structure is During the ceremony, Q is N, P, or S; R A , R B , and R C are each independently hydrogen or unsubstituted or substituted, branched or unbranched C 1 ~C 20 alkyl, aryl, or vinyl, or R A～C Any two of the groups may, together with Q, contain one or more additional heteroatoms selected from N, P, and O. 3 ~C 6 Forming a heterocyclic group, R D is unsubstituted or substituted, branched or unbranched, C 1 ~C 20 C, which may contain one or more heteroatoms selected from alkyl, aryl, vinyl, or N, P, and O; 3 ~C 6 is a cyclic group, where R D further comprises a terminal functional group, and X is F, Cl, Br, or I; Here, R D The terminal functional group is -PO 3 H 2 , -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, During the ceremony, R E , R F , and R G Each is independent, OCH 3 , O.C.H. 2 CH 3 , C.H. 3 or Cl, R H and R I are each independently H or C 1 ~C 20 alkyl, and Y is a halide; method.

9. A bipolar electrode according to any one of claims 1 to 7, Aqueous zinc halide electrolyte and 1. An electrochemical cell comprising:

10. The aqueous zinc halide electrolyte is from about 25 wt.% to about 70 wt.% ZnBr 2 %, about 5 wt.% to about 50 wt.% water, and about 0.05 wt.% to about 10 wt.% of one or more quaternary ammonium agents; Optionally, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 40 wt.% ZnBr 2 %, about 25 wt.% to about 50 wt.% water, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and about 0.5 wt.% to about 10 wt.% of one or more quaternary ammonium agents; Optionally, the one or more quaternary ammonium agents are selected from the group consisting of ammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, trimethylpropylammonium bromide, triethylmethylammonium chloride, trimethylpropylammonium chloride, butyltrimethylammonium chloride, trimethylethylammonium chloride, N-methyl-N-ethylmorpholinium bromide, N-methyl-N-ethylmorpholinium bromide (MEMBr), 1-ethyl-1-methylmorpholinium bromide, N-methyl-N-butylmorpholinium bromide, N-methyl-N-ethylpyrrolidinium bromide, N,N,N-triethyl-N-propylammonium bromide, N-ethyl-N-propylpyrrolidinium bromide, N-propyl-N-butylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, 1-methyl-1-butylpyrrolidinium bromide, N-ethyl-N-(2-chloroethyl)pyrrolidinium bromide, N-methyl-N-hexylpyrrolidinium bromide, N-methyl- or the one or more quaternary ammonium agents comprise an alkyl substituted pyridinium chloride, an alkyl substituted pyridinium bromide, an alkyl substituted morpholinium chloride, an alkyl substituted morpholinium bromide, an alkyl substituted pyrrolidin ...

10. The electrochemical cell of claim 9.

11. A pair of terminal assemblies; at least one bipolar electrode interposed between the pair of terminal assemblies; A battery stack comprising: The bipolar electrodes are A bipolar electrode plate; a cathode substrate loaded with a halogen complexing agent; an aqueous zinc halide electrolyte in contact with the bipolar electrode plates and the cathode substrate; Including, The halogen complexing agent is represented by formula (I): Q + (R A )(R B )(R C )(R D )X - The structure is During the ceremony, Q is N, P, or S; R A , R B , and R C are each independently hydrogen or unsubstituted or substituted, branched or unbranched C 1 ~C 20 alkyl, aryl, or vinyl, or R A～C Any two of the groups may, together with Q, contain one or more additional heteroatoms selected from N, P, and O. 3 ~C 6 Forming a heterocyclic group, R D is unsubstituted or substituted, branched or unbranched, C 1 ~C 20 C, which may contain one or more heteroatoms selected from alkyl, aryl, vinyl, or N, P, and O; 3 ~C 6 is a cyclic group, where R D further comprises a terminal functional group, and X is F, Cl, Br, or I; Here, R D The terminal functional group is -PO 3 H 2 , -Si(R E )(R F )(R G ), or -C(R H )(R I ) Y, During the ceremony, R E , R F , and R G Each is independent, OCH 3 , O.C.H. 2 CH 3 , C.H. 3 or Cl, R H and R I are each independently H or C 1 ~C 20 alkyl, and Y is a halide; Battery stack.

12. the cathode substrate comprises carbon felt, graphite felt, compressed carbon powder, graphite powder, expanded graphite powder, carbon foam, aerogel carbon, xerogel carbon, sol-gel carbon, carbon cloth, carbon paper, or reticulated carbon; and / or the halogen complexing agent is triethylammonium 12-dodecylphosphonate bromide, trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium bromide, N-trimethoxysilylundecyl-N,N,N-tri-n-butylammonium bromide, triethylammonium 12-dodecylphosphonate chloride, pyridinium 12-dodecylphosphonate bromide, N,N-dimethyl-N-octadecylammonium 12-dodecylphosphonate bromide, 1-methyl-3-(dodecylphosphonate)imidazolium bromide, or 1-methyl-3-(hexylphosphonate)imidazolium bromide; and / or The bipolar electrode plates include titanium, TiC, TiN, graphite, or an electrically conductive plastic; The battery stack of claim 11.

13. The aqueous zinc halide electrolyte is from about 25 wt.% to about 70 wt.% ZnBr 2 %, about 5 wt.% to about 50 wt.% water, and about 0.05 wt.% to about 10 wt.% of one or more quaternary ammonium agents; Optionally, the aqueous zinc halide electrolyte comprises about 25 wt.% to about 40 wt.% ZnBr 2 %, about 25 wt.% to about 50 wt.% water, about 5 wt.% to about 15 wt.% KBr, about 5 wt.% to about 15 wt.% KCl, and about 0.5 wt.% to about 10 wt.% of one or more quaternary ammonium agents; The battery stack according to claim 11 or 12.

14. The one or more quaternary ammonium agents may be selected from the group consisting of ammonium chloride, tetraethylammonium bromide, tetraethylammonium chloride, trimethylpropylammonium bromide, triethylmethylammonium chloride, trimethylpropylammonium chloride, butyltrimethylammonium chloride, trimethylethylammonium chloride, N-methyl-N-ethylmorpholinium bromide, N-methyl-N-ethylmorpholinium bromide (MEMBr), 1-ethyl-1-methylmorpholinium bromide, N-methyl-N-butylmorpholinium bromide, N-methyl-N-ethylpyrrolidinium bromide, N,N,N-triethyl-N-propylammonium bromide, N-ethyl-N-propylpyrrolidinium bromide, N-propyl-N-butylpyrrolidinium bromide, N-methyl-N-butylpyrrolidinium bromide, 1-methyl-1-butylpyrrolidinium bromide, lysinium, N-ethyl-N-(2-chloroethyl)pyrrolidinium bromide, N-methyl-N-hexylpyrrolidinium bromide, N-methyl-N-pentylpyrrolidinium bromide, N-ethyl-N-pentylpyrrolidinium bromide, N-ethyl-N-butylpyrrolidinium bromide, trimethylene-bis(N-methylpyrrolidinium) dibromide, N-butyl-N-pentylpyrrolidinium bromide, N-methyl-N-propylpyrrolidinium bromide, N-propyl-N-pentylpyrrolidinium bromide, 1-ethyl-4-methylpyridinium bromide, 1-ethyl-2-methylpyridinium bromide, 1-butyl-3-methylpyridinium bromide, cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, cetyltriethylammonium bromide, and any combination thereof; the one or more quaternary ammonium agents include alkyl-substituted pyridinium chlorides, alkyl-substituted pyridinium bromides, alkyl-substituted morpholinium chlorides, alkyl-substituted morpholinium bromides, alkyl-substituted pyrrolidinium chlorides, alkyl-substituted pyrrolidinium bromides, or any combination thereof; The battery stack of claim 13.

15. 15. The battery stack of any one of claims 11 to 14, wherein the self-discharge rate of the battery stack is about 29% to about 34% lower in a single cycle compared to an equivalent battery stack that does not include the halogen complexing agent.

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