阅读说明：本技术 电池隔膜和使用该电池隔膜的电池 (Battery separator and battery using the same ) 是由 理查德·I·马塞勒 于 2018-04-30 设计创作，主要内容包括：一种电池,其包括隔膜,所述隔膜包含含有苯乙烯和乙烯基苄基-R<Sub>s</Sub>的共聚物的离子传导聚合物组合物,其中R<Sub>s</Sub>是带正电的环胺基。离子传导聚合物组合物可以是膜的形式。离子传导聚合物组合物可以包含苯乙烯、乙烯基苄基-R<Sub>s</Sub>和乙烯基苄基-R<Sub>x</Sub>的三元共聚物,其中R<Sub>s</Sub>是带正电的环胺基,R<Sub>x</Sub>是选自由Cl、OH以及OH或Cl与除环胺或简单胺外的物种之间的反应产物组成的组中的至少一种组分,所述乙烯基苄基-R<Sub>x</Sub>基团的总重量大于所述膜的总重量的1％,并且所述乙烯基苄基-R<Sub>s</Sub>基团的总重量是所述膜的总重量的15％以上。(A battery comprising a separator comprising a polymer containing styrene and vinylbenzyl-R s Ion-conducting polymer composition of a copolymer of (1), wherein R s Is a positively charged cyclic amine group. The ion-conducting polymer composition may be in the form of a membrane. The ion conducting polymer composition may comprise styrene, vinylbenzyl-R s And vinylbenzyl-R x Wherein R is s Is a positively charged cyclic amino group, R x Is to selectAt least one component from the group consisting of Cl, OH and reaction products between OH or Cl and a species other than cyclic or simple amines, the vinylbenzyl-R x The total weight of groups is greater than 1% of the total weight of the membrane, and the vinylbenzyl-R s The total weight of the groups is more than 15% of the total weight of the film.)

1. A battery comprising a separator comprising a polymer containing styrene and vinylbenzyl-R_sion-conducting polymer composition of a copolymer of (1), wherein R_sis a positively charged cyclic amine group.

2. the battery of claim 1, wherein the ionically conductive polymer composition comprises styrene, vinylbenzyl-R_sAnd vinylbenzyl-R_xThe terpolymer of (a), wherein:

R_sIs a cyclic amine group with positive charge,

R_xIs at least one component selected from the group consisting of Cl, OH and reaction products between OH or Cl and an inorganic species or an organic species other than an amine,

Said vinylbenzyl-R_xThe total weight of groups is greater than 1% of the total weight of the terpolymer, and

Wherein said vinylbenzyl-R_sThe total weight of groups is more than 15% of the total weight of the terpolymer.

3. The battery of claim 1, wherein R_sSelected from the group consisting of: imidazolePyridine, and their usepyrazolesPyrrolidine, pyrrolidineazoles, azolesPyrimidine, pyrimidinePiperidine, piperidine and their use as a medicamentIndole, indoleAnd triazines。

4. The battery of claim 3, wherein R_sIs an imidazole。

5. The battery of claim 4, wherein the imidazoleIs tetramethylimidazole。

6. The battery of claim 3, wherein R_sIs pyridine。

7. The battery of claim 6, wherein the pyridineIs an alkyl pyridine。

8. The battery of claim 7, wherein the pyridineis pentamethylpyridine。

9. The battery of claim 1, wherein the copolymer has a molecular weight of 1000 to 10,000,000 atomic units (A.U.).

10. The battery of claim 9, wherein the copolymer has a molecular weight of 10,000 to 1,000,000a.u.

11. The battery of claim 10, wherein the copolymer has a molecular weight of 25,000 to 250,000a.u.

12. The battery of claim 1, wherein the ionically conductive polymer composition forms at least a portion of the separator.

13. The battery of claim 12, wherein the battery separator has a thickness of 10 to 300 microns.

14. the battery of claim 1, wherein the ionically conductive polymer composition further comprises at least one component selected from the group consisting of:

Linear or substituted polyolefins;

A polymer comprising uncharged cyclic amine groups;

A polymer comprising at least one of phenylene and phenyl;

A polyamide; and

A reaction product of a component having two carbon-carbon double bonds.

15. The battery of claim 14, wherein:

The polyolefin comprises at least one of polyethylene, polypropylene and polytetrafluoroethylene;

The polymer comprising uncharged cyclic amine groups is polybenzimidazole;

The polymer containing at least one of a phenylene group and a phenyl group is a polyphenylene ether;

The component having two carbon-carbon double bonds is at least one of divinylbenzene and butadiene; and is

the polyamide component is nylon 6 or nylon 66.

16. The battery of claim 1, further comprising an electrode comprising at least one d-block element.

17. The battery of claim 16, wherein the d-block element is selected from the group consisting of: v, Cr, Mn, Fe, Co, Ni, Cu, and Zn.

18. The battery of claim 17, wherein the d-block element is bound to an organic ligand.

19. The battery of claim 1, wherein the copolymer is crosslinked.

20. The battery of claim 1, wherein the separator comprises a porous polymer having an average pore size of 0.5 to 3 nm.

21. The battery of claim 1, wherein the separator further comprises clay.

22. The battery of claim 1, wherein the separator further comprises a zeolite.

23. The battery of claim 1, wherein the separator further comprises a metal oxide.

24. the battery of claim 1, wherein the separator further comprises a nanofiltration or ultrafiltration membrane.

25. The battery of claim 1, wherein the separator further comprises alternating layers of:

(a) An organic molecule or polymer comprising an anionic group; and

(b) An organic molecule or polymer comprising a cationic group.

26. The battery of claim 1, wherein the separator further comprises a molecule or polymer capable of chelating a metal ion.

27. the battery of claim 1, wherein the separator further comprises a molecule or polymer having a carboxylate ligand.

28. The battery of claim 1, wherein the separator further comprises a cation exchange ionomer.

29. The battery of claim 27, wherein the cation exchange ionomer comprises perfluorosulfonic acid.

30. The battery of claim 1, wherein the separator further comprises a reverse osmosis membrane.

31. The battery of claim 1, wherein the separator further comprises a positively charged cyclic amine surfactant.

32. The battery of claim 30, wherein the positively charged cyclic amine surfactant has the form:

R₁₈-R₁₉-R₂₀-R₂₁-R₂₂，

Wherein:

R₁₉And R₂₁is composed of positively charged ringsThe difunctional group of the amine(s) is,

R₂₀Is a difunctional group selected from the group consisting of straight chain alkyl, branched chain alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl and heteroarylalkyl groups having up to 20 carbons,

R₁₈and R₂₂Is a monofunctional group independently selected from the group consisting of straight chain alkyl, branched chain alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroarylalkyl, wherein R is₁₈And R₂₂Each of which contains unreacted double bonds.

33. The battery of claim 31, wherein R₁₉And R₂₁Including the elimination of imidazolesThe outer positively charged cyclic amine.

34. a positively charged cyclic amine surfactant, wherein the positively charged cyclic amine surfactant has the form:

R₁₈-R₁₉-R₂₀-R₂₁-R₂₂，

Wherein:

R₁₉And R₂₁is composed of imidazole removingAn external positively charged bifunctional group of a cyclic amine;

R₂₀is a difunctional group selected from the group consisting of straight chain alkyl, branched chain alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroalkylaryl groups having up to 20 carbons; and is

R₁₈And R₂₂Is a difunctional group independently selected from the group consisting of straight chain alkyl, branched chain alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl and heteroarylalkyl, wherein R is₁₈And R₂₂Each of which contains a polymerizable double bond.

35. A membrane comprising a polymerized positively charged cyclic amine surfactant, wherein the positively charged cyclic amine surfactant has the form:

R₁₈-R₁₉-R₂₀-R₂₁-R₂₂，

Wherein:

R₁₉And R₂₁Is composed of imidazole removingAn external positively charged bifunctional group of a cyclic amine;

R₂₀Is a difunctional group selected from the group consisting of straight chain alkyl, branched chain alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroalkylaryl;

R₁₈and R₂₂Is a difunctional group independently selected from the group consisting of straight chain alkyl, branched chain alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl and heteroarylalkyl, wherein R is₁₈And R₂₂Each of which contains a polymerizable double bond.

36. The film of claim 33, wherein R₁₈、R₂₀And R₂₂Having up to 20 carbon atoms.

37. The membrane of claim 34, wherein the battery separator further comprises a porous support.

38. a membrane useful as a battery separator, said membrane comprising a polymer comprising styrene and vinylbenzyl-R_sIon-conducting polymer composition of a copolymer of (1), wherein R_sIs a positively charged cyclic amine group.

Technical Field

The present invention relates to a separator for an electrochemical device. In particular, the present invention relates to a separator for a battery and the resulting battery.

Background

Secondary lithium ion batteries now power most portable electronic devices, but lithium is highly flammable and lithium ion batteries need to be replaced more frequently than is normally required. A number of alternative battery chemistries and designs have been proposed, but they have inherent disadvantages.

Conventional alkaline batteries have been in use for many years. Alkaline batteries have reasonable energy density, but they are difficult to recharge once fully discharged due to zinc crossover during discharge and hydrogen formation during the recharge process.

In Lin et al, Science, stage 349,6255, page 1529-1532 (2015), a novel battery with chemistry to avoid hydrogen formation is described. However, electricity of Linthe cell was subjected to a high resistance (about 0.895 ohm-cm at room temperature)²) The use of the membrane of (a).

In Parker et al, Science 356,6336 phase, page 415-418 (2017), a new battery is described that can be discharged to 40% capacity and recharged. However, zinc crossover occurs at higher discharges, limiting performance.

summary of The Invention

by using a catalyst comprising a catalyst containing styrene and vinylbenzyl-R_sthe battery separator of the anionic conductive polymer composition of copolymer (a) wherein R is a polymer of formula (b), overcomes the disadvantages of the prior batteries_sIs a positively charged cyclic amine group.

In the foregoing improved battery separator, the ion conducting polymer composition preferably comprises styrene, vinylbenzyl-R_sAnd vinylbenzyl-R_xWherein R is_sIs a positively charged cyclic amino group, R_xIs at least one component selected from the group consisting of Cl, OH and reaction products of OH or Cl with species other than cyclic or simple amines, vinylbenzyl-R_xThe total weight of the radicals being greater than 0.3% of the total weight of the film, and vinylbenzyl-R_sThe total weight of the groups is more than 15% of the total weight of the film.

in one embodiment of the foregoing battery, R_sSelected from the group consisting of: imidazolePyridine compoundPyrazolespyrrolidine as a therapeutic agentAzole compoundsPyrimidinesPiperidine derivativesIndolesand triazinesPreferred is imidazoleAnd pyridine

In another embodiment of the polymer composition, R_sIs an imidazoleImidazolePreferably an alkyl imidazoleMore preferably tetramethylimidazole

In another embodiment of the polymer composition, R_sIs pyridinePyridine compoundPreferably an alkyl pyridineMore preferably pentamethylpyridine

In another embodiment of the polymer composition, the molecular weight of the polymer is 1000 to 10,000,000 atomic units (A.U.), preferably 10,000 to 1,000,000a.u., and most preferably 25,000 to 250,000a.u.

In another embodiment, the polymer composition is in the form of a film. The preferred thickness of the film is 10 to 300 microns.

In another embodiment, the polymer composition is crosslinked.

In another embodiment, the polymer composition further comprises at least one component selected from the group consisting of:

(a) linear or substituted polyolefins;

(b) A polymer comprising uncharged cyclic amine groups;

(c) A polymer comprising at least one of phenylene and phenyl;

(d) A polyamide; and

(e) A reaction product of a component having two carbon-carbon double bonds.

In another embodiment, the polyolefin comprises at least one of polyethylene, polypropylene, and/or polytetrafluoroethylene. The polymer comprising uncharged cyclic amine groups is preferably polybenzimidazole. The polymer containing at least one of phenylene group and phenyl group is preferably polyphenylene ether. The component having two carbon-carbon double bonds is preferably divinylbenzene or butadiene. The preferred polyamide component is polybenzimidazole.

In another embodiment, the polymer membrane further comprises a porous layer, wherein the pores have a diameter of 0.5 to 3 nm.

In another embodiment, the aforementioned battery further comprises at least one d-block element from the periodic table of elements. The d-block element is preferably selected from the group of V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Cd and Hg. The d-block element may be bound to an organic ligand.

In another embodiment, the polymer film further comprises a clay.

In another embodiment, the polymer membrane further comprises a zeolite.

In another embodiment, the polymer film further comprises a metal oxide.

In another embodiment, the polymeric membrane further comprises a nanofiltration or ultrafiltration membrane.

In another embodiment, the polymer film further comprises alternating layers of:

(a) an organic molecule or polymer comprising an anionic group; and

(b) An organic molecule or polymer comprising a cationic group.

In another embodiment, the polymeric membrane further comprises a molecule or polymer capable of chelating a metal ion.

In another embodiment, the polymeric film further comprises a molecule or polymer having a carboxylate ligand.

In another embodiment, the polymeric membrane further comprises a cation exchange ionomer. The cation exchange ionomer preferably comprises perfluorosulfonic acid.

In another embodiment, the polymeric membrane further comprises a reverse osmosis membrane.

In another embodiment, the polymeric membrane comprises a polymeric positively charged cyclic amine surfactant.

Preferably, the positively charged cyclic amine surfactant has the form:

R₁₈-R₁₉-R₂₀-R₂₁-R₂₂

Wherein:

R₁₉-and-R₂₁-is a bifunctional group comprising a positively charged cyclic amine;

R₂₀-is a bifunctional group selected from linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroalkylaryl; and is

R₁₈And R₂₂Each independently selected from the group consisting of linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroarylalkyl, wherein the monofunctional group R₁₈And R₂₂Each of which is contained inOne less unreacted double bond.

Preferably, R₁₉And R₂₁Is to remove imidazoleThe outer positively charged cyclic amine.

Preferably, R₁₈、R₂₀And R₂₂Containing not more than 20 carbon atoms.

In another embodiment, the battery separator comprises a polymeric positively charged cyclic amine surfactant. Preferably, the positively charged cyclic amine surfactant has the form:

R₁₈-R₁₉-R₂₀-R₂₁-R₂₂，

Wherein:

R₁₉And R₂₁Is a positively charged cyclic amine;

R₂₀Selected from the group consisting of linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroalkylaryl, but not a polymer; and is

R₁₈And R₂₂Independently selected from the group consisting of linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroarylalkyl which contain unreacted double bonds.

The positively charged cyclic amine is preferably not an imidazoleR₁₈、R₂₀And R₂₂Preferably containing no more than 20 carbon atoms.

Brief Description of Drawings

Fig. 1 is a schematic diagram generally depicting a cell design.

detailed description of illustrative embodiments

It is to be understood that the methods are not limited to the particular methodology, protocols, and reagents described herein as these may vary, as will be appreciated by those familiar with the art to which this relates. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the methods. It should also be noted that, as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a linker" is a reference to one or more linkers and equivalents thereof known to those skilled in the art. Similarly, the phrase "and/or" is used to indicate that one or both of the recited circumstances may occur, e.g., a and/or B includes (a and B) as well as (a or B).

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the methods belong. Embodiments of the method and various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments and/or illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale and features of one embodiment may be used with other embodiments, even if not explicitly recited herein, as will be appreciated by the skilled artisan.

Any numerical range recited herein includes all values from the lower value to the upper value in increments of one unit provided that there is a separation of at least two units between any lower value and any higher value. For example, if it is stated that the concentration of a component or a value of a process variable (such as, for example, dimensions, angular dimensions, pressure, time, etc.) is, for example, from 1 to 98, specifically from 20 to 80, more specifically from 30 to 70, it is intended that the present specification expressly recite values such as 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc. For values less than one, one unit is considered to be 0.0001, 0.001, 0.01, or 0.1, as appropriate. These are only examples of what is specifically intended, and all possible combinations of numerical values between the lowest value and the highest value are treated in a similar manner.

In addition, provided immediately below is a "definitions" section, wherein specific terms relating to the method are specifically defined. Specific methods, devices, and materials are described, but any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the methods.

Definition of

The term "polymer electrolyte membrane" refers to both cation exchange membranes, which typically comprise a polymer having a plurality of covalently linked negatively charged groups, and anion exchange membranes, which typically comprise a polymer having a plurality of covalently linked positively charged groups. Typical cation exchange membranes include proton conducting membranes such as perfluorosulfonic acid polymers available under the trade name "NAFION" from e.i. du Pont DE nemours and Company (DuPont) of Wilmington, DE.

the term "anion exchange cell" as used herein refers to a cell having an anion exchange membrane separating a negative electrode from a positive electrode.

The term "faradaic efficiency" as used herein refers to the fraction of electrons applied to the cell that participate in the desired reaction.

The term "hydrogen evolution reaction", also referred to as "HER", as used herein, refers to the electrochemical reaction 2H⁺+2e^-→H₂。

The term "Millipore water" is water produced by a Millipore filtration system having a resistivity of at least 18.2 megaohm-centimeters.

The term "imidazole" as used herein"refers to a positively charged ligand containing an imidazole group. Which includes unmodified (bare) imidazoles or substituted imidazoles. Specifically included are ligands of the form:

Wherein R is₁-R₅Each independently selected from the group consisting of hydrogen, halides, linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, heteroalkylaryl, and polymers thereof, vinyl as described hereina benzyl copolymer.

The term "pyridine" as used herein"refers to a positively charged ligand containing a pyridine group. Which include unmodified or substituted pyridines. Specifically included are ligands of the form:

Wherein R is₆-R₁₁Each independently selected from hydrogen, halides, linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, heteroalkylaryl, and polymers thereof, such as vinylbenzyl copolymers as described herein.

The term "phosphonium" as used herein refers to positively charged ligands containing phosphorus. Which includes substituted phosphorus. Specifically included are ligands of the form:

P⁺(R₁₂R₁₃R₁₄R₁₅)，

Wherein R is₁₂-R₁₅Each independently selected from hydrogen, halides, linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, heteroalkylaryl, and polymers thereof, such as vinylbenzyl copolymers as described herein.

The term "positively charged cyclic amine" as used herein refers to a positively charged ligand containing a cyclic amine. It specifically includes imidazolesPyridine compoundPyrazolesPyrrolidine as a therapeutic agentazole compoundsPyrimidinesPiperidine derivativesIndolesTriazineAnd polymers thereof, such as the vinylbenzyl copolymers described herein.

The term "surfactant" as used herein is a molecule having a hydrophilic head group and a hydrophobic tail.

The term "positively charged cyclic amine surfactant" as used herein refers to a surfactant whose head group contains a positively charged cyclic amine.

The term "polymerizable positively charged cyclic amine surfactant" as used herein refers to a positively charged cyclic amine surfactant whose one or more tail groups contain a double bond or other group that can be polymerized.

The term "simple amine" refers to the following forms of material:

N(R₁₆R₁₇R₁₈)，

Wherein R is₁₆、R₁₇And R₁₈Each independently selected from hydrogen, linear alkyl, branched alkyl, cycloalkyl, heteroalkyl, aryl, heteroaryl, alkylaryl, and heteroalkylaryl, but not a polymer.

The term "PIM" as used herein refers to a polymer having intrinsic microporosity.

The term "clay" or "clay mineral" as used herein refers to a material comprising hydrated aluminum phyllosilicates.

The term "MOF" as used herein refers to a metal-organic framework.

The term "d-block element" as used herein refers to one or more of the following: ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg.

The term "nanofiltration membrane" as used herein refers to a membrane having 1nm to 50nm diameter pores passing through the membrane.

the term "reverse osmosis membrane" as used herein refers to a membrane designed for reverse osmosis. It is a semi-permeable membrane that uses pore sizes less than 1nm to remove ions, molecules and larger molecules from water and other solvents.

The term "PSTMIM solution" as referred to herein refers to a solution prepared as described in specific example 1.

DETAILED DESCRIPTIONS

figure 1 shows a simple alkaline cell. The battery is composed of a negative electrode 100, a positive electrode 101, and a membrane electrolyte 102 interposed therebetween. The negative electrode is typically zinc, copper or silver. The positive electrode is typically a metal oxide or hydroxide such as MnO₂Or NiOOH. During discharge, the following reactions occur on the negative electrode

Zn(s)→Zn²⁺(aq)+2e^-(1)

Zn²⁺(aq)+4OH^-(aq)→Zn(OH)₄ ^2-(aq)(2)

And the following reaction occurs at the positive electrode:

2MnO₂(s)+H₂O(l)+2e^-→Mn₂O₃(s)+2OH^-(aq)(3)

The following reactions can also take place on the negative or positive electrode:

Zn(OH)₄ ^2-(aq)→ZnO(s)+H₂O(l)+2OH^-(aq)(4)

Zinc dissolves into the KOH solution during reaction 1 and reacts rapidly with hydroxyl to form a dissolved complex. Zn (OH)₄ ^2-Some of the complexes react on the negative electrode to produce zinc oxide precipitates, butIs Zn (OH)₄ ^2-Some of the complex diffuses through the film 102 during discharge and is deposited on the positive electrode 101.

Recharging the battery requires reversing the reaction to redeposit the metallic zinc on the negative electrode and Mn on the positive electrode₂O₃And (4) reoxidizing. The zinc still in the negative electrode can be efficiently reconverted to metallic zinc. Dendrite formation should be limited and techniques exist to do so. However, zinc on the positive electrode is difficult to regenerate. For the reducing conditions to dissolve the zinc oxide on the positive electrode, a net operation (running at net) is required. For adding Mn to the positive electrode₂O₃For reoxidation oxidation conditions, a net run is also required. Since it is not possible to reduce zinc and Mn simultaneously₂O₃Oxidation, which presents problems.

In principle, the amount of zinc deposited on the positive electrode can be limited by appropriately adjusting the separator. For example, if the membrane is designed to prevent or block Zn (OH)₄ ^2-But allowing hydroxyl radicals to pass through the membrane, the deposition of ZnO on the positive electrode can be avoided, and the cell can therefore be regenerated.

It is noted that the battery will not be efficient if the membrane resistance for hydroxyl transport is too high. In principle, however, a suitable separator will enable the production of a renewable alkaline battery.

in the present application, separator compositions are disclosed that exhibit low resistance to hydroxyl transport, but limit the transport of copper and zinc ions through the membrane.

Specific example 1: preparation of improved membranes for alkaline batteries

Preparation of PSTMIM Polymer solution

The first step is to prepare a polymer solution which will be referred to as a PSTMIM polymer solution.

Step 1: and (5) purifying the monomer.Inhibitor-free vinylbenzyl chloride (VBC) was prepared by adding a volume V of VBC (Dow Chemical, Midland, MI) and a volume equal to V/4 of 0.5 wt% aqueous sodium hydroxide solution (Sigma Aldrich, st. louis, MO) to a separatory funnel. Followed by stirring the funnel to remove the waterMixing with VBC, holding the mixture stationary until it forms an organic layer and an inorganic layer, and then decanting the VBC. This process was repeated until the water layer showed no visible color change, which was approximately five times. This procedure was repeated using deionized water instead of sodium hydroxide solution until the aqueous layer pH was neutral. The washed VBC was placed in a refrigerator overnight before weighing to convert most of the remaining water to ice, and then the ice was separated from the VBC by decantation.

Step 2: preparation of inhibitor styrene.styrene (Sigma Aldrich, st. louis, MO) was fed through a 60mL syringe filled with Sigma-Aldrich 311340 inhibitor remover to prepare inhibitor-free styrene.

And step 3: and (3) synthesizing a copolymer.Poly (vinylbenzyl chloride-co-styrene) was then synthesized by: a solution of inhibitor-free styrene (689g, 6.62mol) and vinylbenzyl chloride (573g, 3.75mol) in chlorobenzene (999g) was heated under nitrogen at 60 ± 2 ℃ for 24 hours in a heating mantle using AIBN (α, α' -azobisisobutyronitrile) (Sigma Aldrich, st. louis, MO) (11.85g, 0.94 wt% based on total monomer weight) as initiator. The copolymer poly (VBC-co-St) was precipitated in methanol, then washed thoroughly and dried at 60 ℃ overnight.

And 4, step 4: PSTMIM solution preparation.1,2,4, 5-tetramethylimidazole (172.8g, 1.3914mol) (TCI, Montgomeryville, Pa.), poly (VBC-co-St) synthesized above (550g), anhydrous Methoxyisopropanol (MIP) (1600g, Sigma-Aldrich), Divinylbenzene (DVB) (Sigma Aldrich, St. Louis, MO) (22g, 0.169mol), and AIBN (0.22g) were mixed under nitrogen flow. The mixture was stirred and heated to 65 ℃ for about 48 hours until the viscosity reached about 800 cp. The resulting solution is referred to herein as a "PSTMIM solution".

PSTMIM film preparation

A PSTMIM film was prepared by casting the PSTMIM polymer solution prepared above directly onto a polyethylene terephthalate (PET) backing layer (LOPAREX LLC, Eden, NC). The thickness of the solution on the backing was controlled by an BKY (Geretsried, germany) automatic film applicator with an adjustable doctor blade. The film was then dried in a vacuum oven at an elevated temperature of 70 ℃ and held for 1 hour. After a further hour in a slowly decreasing vacuum oven, the film was removed from the oven and placed in a 1M KOH (City Chemicals, West Haven, CT) solution overnight, during which time the film peeled off the liner. The KOH solution was replaced twice. In this way, the "chloride form" anion exchange membrane is converted to the hydroxide form.

U.S. patent application publication No. US 2017/0128930A 1 discloses that films prepared in this manner contain styrene, vinylbenzyl-R_sAnd vinylbenzyl-R_xWherein R is_sIs a positively charged cyclic amine group, and R_xIs at least one component selected from the group consisting of Cl, OH, and reaction products between OH or Cl and an inorganic species or an organic species other than an amine.

examples of inorganic species include metal ions in the starting material. Examples of organic species include alcohols used as solvents or otherwise added during synthesis.

U.S. patent application publication No. US 2017/0128930A 1 also discloses that when vinylbenzyl-R_xThe total weight of the groups being greater than 1% of the total weight of the terpolymer and vinylbenzyl-R_sExcellent properties are obtained when the total weight of the groups is more than 15% of the total weight of the terpolymer.

Membrane characterization

Membrane conductivity measurement

By measuring IrO with platinum catalyst positive electrode₂Catalyst negative electrode and 5cm of the membrane to be tested between the positive and negative electrodes²Electrochemical Impedance Spectroscopy (EIS) of Fuel Cell Technologies (Albuquerque, NM) cells to test the thickness-direction conductivity of the membrane.

The positive electrode was prepared as follows: 100mg of Pt nanoparticles (Premion, Alpha Aesar) were suspended in 2ml of isopropanol, 1ml of deionized water, and 0.2ml of a 5% dispersion of an ionomer available under the trade name NAFION (DuPont). The mixture was sonicated in a water bath for 10 minutes. The resulting positive ink was sprayed onto 5cm x of Sigracet 39BC carbon paper (SGLGroup, Meiningen, Germany)5cm pieces. The electrodes were dried in an oven at 80 ℃ for 20 minutes and cut into 4 pieces of 2.5cm x 2.5cm for testing. The catalyst loading was about 2mg/cm²。

The negative electrode was prepared in a similar manner, but using IrO₂Nanoparticles (Premion, Alfa Aesar, inc.) replace the platinum nanoparticles. The catalyst ink was sprayed onto a 6cm x 6cm stainless steel fiber cloth (AISI 316L-WNR, Bekaert, Zwevegem, Belgium). The electrodes were dried in an oven at 80 ℃ for 20 minutes and cut into 4 pieces of 3cm x 3cm for testing. The actual loading was about 2mg/cm²。

the film prepared above was sandwiched between a Pt cathode and IrO as described above₂Between the cathodes, and mounted to 5cm²1M KCl was pumped into the negative and positive electrodes in Fuel Cell hardware (Fuel Cell Technologies, Albuquerque, NM), and the electrochemical impedance spectra of the cells were measured with a potentiostat coupled to a frequency analyzer (Solartron,1287+ 1255B). Assuming the cell resistance is the membrane resistance, the contribution from the resistance of other components such as the electrodes and the cell hardware is ignored. The area specific resistance (R) was determined by the intersection of the EIS spectrum on the real axis.

table 1 shows the Area Specific Resistance (ASR) measured as described above.

TABLE 1

Measured specific resistance (ASR)

Origin of origin	temperature of	Ohm-cm of ASR2	Leakage current, μ A/cm2
				Lin et al1	25℃	0.895	<2.5
Lin et al1	43℃	0.560
				Detailed description of the preferred embodiment 1	27℃	0.284	<0.7
Detailed description of the preferred embodiment 1	43℃	0.127

¹lin et al, Science, stage 349,6255, page 1532 (2015) 1529-.

It should be noted that the area specific resistance of the new film is less than one third of the area specific resistance of Lin et al. Therefore, the energy loss will be low. The leakage current is also small, further improving the performance of the novel film.

Cu²⁺And Zn²⁺Crossing measurement

also measure Cu²⁺The rate of ion passage through the membrane. The limiting current was measured using the following method:

The membrane was sandwiched between a sheet of stainless steel fiber felt (positive electrode) and a sheet of Cu mesh (negative electrode), and mounted at 5cm²Fuel Cell Technologies (Albuquerque, NM) Fuel Cell hardware. By mixing CuSO₄(Sigma Aldrich, St. Louis, Mo.) in Millipore Water to prepare 1M CuSO₄And (3) solution. Mixing CuSO₄the solution is fed to the anode flow field, andDeionized (DI) water is fed to the positive flow field. Cu crossing the membrane from cathode to anode²⁺Is reduced to Cu at the positive electrode⁰While the Cu negative electrode is dissolved into the anodic electrolyte (anolyte) to maintain the Cu during the measurement²⁺Is constant. Cu of current-carrying film²⁺Is limited in permeability. Linear Scanning Voltammograms (LSV) were made by scanning potentials from 0.05 to-0.3V at 2 mV/s. The limiting current density occurs at-0.2 to-0.3V. Using limiting current density as Cu passing through the film²⁺A measure of crossing.

Zn is also measured²⁺The rate of ion passage through the membrane. The limiting current was measured using the following method:

the film was sandwiched between a piece of silver film (positive electrode) and a piece of copper mesh (negative electrode), and mounted at 5cm²fuel Cell Technologies Fuel Cell hardware. By reacting ZnNO₃(Sigma Aldrich, St. Louis, Mo.) in Millipore Water to prepare 1M ZnNO₃And (3) solution. ZnNO is reacted with₃The solution was fed to the anode flow field and DI water was fed to the cathode flow field. Zn crossing the film from cathode to anode²⁺Is reduced to Zn at the anode⁰. Zn with current passing through the membrane²⁺Is limited in permeability. Linear Scanning Voltammograms (LSV) were made by scanning potentials from-1.0 to-1.5V at 2 mV/s. The limiting current density occurs at-1.3 to-1.4V.

Table 2 shows the results obtained. Note that the limit Cu²⁺The current is only 10mA/cm². This is in contrast to the higher than 1,000mA/cm reported in commonly owned U.S. patent application Ser. No. 15/406,909²The hydroxide currents of (a) were compared.

TABLE 2

Comparison of the Properties of the films contemplated herein

Comparative example 1: amine coated targarray film

Measurements were also performed using amine coated targarray (Kirkland, canada) battery separators. Most battery separators have high resistance in 1M KOH. Conductivity as low as 0.1mS/cm was measured with commercial battery separators. The exception is ceramic coated porous polypropylene membranes. When the ceramic coated porous polypropylene separator was coated with an amine surfactant, reasonable conductivity was obtained within hours before the amine was washed away.

In detail, a 25 μm thick ceramic coated porous polypropylene separator # SH624w22VVV (Targarray, Montreal, Canada) membrane was soaked in a solution containing 1 wt% BIO-SOFTR N-300(Stephan, Northfield, IL) for two minutes. The other 99% of the solution consisted of 30% deionized water and 70 wt% isopropanol (Sigma Aldrich, st. louis, MO). The film was then dried in an oven at 60 ℃ for 1 hour before use.

Next, copper and zinc crossover and membrane conductivity were measured using the procedure in specific example 1.

The figure of merit (FOM) for a given membrane is defined as:

Table 2 shows the figure of merit for a number of embodiments.