KR102264516B1 - Ion exchanging membrane, method for manufacturing the same and energy storage system comprising the same - Google Patents

Abstract

The present invention relates to an ion exchange membrane, a method for manufacturing the same, and an energy storage device including the same, wherein the ion exchange membrane includes a support layer, a polymer electrolyte membrane disposed on one surface of the support layer, and including an ion conductor, and the support layer and the and an interfacial adhesive layer positioned between the polymer electrolyte membranes.
Since the ion exchange membrane includes a support layer, the ion permeation path is increased and the movement of vanadium ions and bromine ions is suppressed, thereby preventing these ions from causing a degradation reaction in the polymer electrolyte membrane or lowering the voltage efficiency. , the interfacial bonding force between the support layer and the polymer electrolyte membrane is high, and the difference between the swelling property of the support layer and the swelling property of the polymer electrolyte membrane is minimized, so that the structural stability is excellent.

Description

Ion exchange membrane, method for manufacturing the same, and energy storage device including same {ION EXCHANGING MEMBRANE, METHOD FOR MANUFACTURING THE SAME AND ENERGY STORAGE SYSTEM COMPRISING THE SAME}

The present invention relates to an ion exchange membrane, a method for manufacturing the same, and an energy storage device including the same, and more particularly, to an ion exchange membrane in which movement of vanadium ions and bromine ions is suppressed and structural stability is excellent, a manufacturing method thereof, and energy comprising the same It's about storage.

In order to solve the problems of depletion of fossil fuels and environmental pollution, efforts are being made to save fossil fuels or apply renewable energy to more fields by improving use efficiency.

Renewable energy sources such as solar and wind are being used more efficiently than ever before, but these energy sources are intermittent and unpredictable. Due to these characteristics, dependence on these energy sources is limited, and the proportion of renewable energy sources among the current primary power sources is very low.

Rechargeable batteries provide a simple and efficient method of storing electricity, so efforts are being made to miniaturize them and increase their mobility to use them as intermittent auxiliary power sources or as power sources for small household appliances such as laptops, tablet PCs, and mobile phones.

Among them, a redox flow battery (RFB) is a secondary battery that can store and use energy for a long period of time by repeating charging and discharging by an electrochemical reversible reaction of an electrolyte. The stack and electrolyte tank, which determine the capacity and output characteristics of the battery, are configured independently of each other, so the design of the battery is free and the installation space is small.

In addition, the redox flow battery has a load leveling function that can respond to a sudden increase in power demand by installing it in a power plant, power system, or building, and a function to compensate or suppress power failure or instantaneous low voltage, etc., and can be freely combined as needed. It is a very promising energy storage technology and is a system suitable for large-scale energy storage.

The redox flow battery is generally composed of two separate electrolytes. One stores the electroactive material in the negative electrode reaction and the other is used in the positive electrode reaction. In an actual redox flow battery, the electrolyte reaction is different between the anode and the cathode, and since the electrolyte flow phenomenon exists, a pressure difference occurs between the anode side and the cathode side. In the all-vanadium-based redox flow battery, which is a representative redox flow battery, the reactions of the positive and negative electrolytes are shown in Schemes 1 and 2, respectively.

[Scheme 1]

[Scheme 2]

Therefore, an ion exchange membrane with improved physical and chemical durability is required to overcome the pressure difference at both electrodes and to exhibit excellent battery performance even after repeated charging and discharging, and in the redox flow battery, the ion exchange membrane is a system It is a core material that accounts for about 10% of the price.

As such, in the redox flow battery, the ion exchange membrane is a key component that determines the battery life and price. For the commercialization of the redox flow battery, the selective permeability of the ion exchange membrane is high, so that the crossover of vanadium ions is It should be low, electrical resistance should be small, ionic conductivity should be high, and mechanical and chemical stability should be high durability and low price.

Meanwhile, the polymer electrolyte membrane, which is currently commercialized as an ion exchange membrane, has been used for several decades and is a field that is being continuously studied. Recently, direct methanol fuel cell (DMFC) or polymer electrolyte membrane fuel cell (PEMFC) Numerous studies on ion exchange membranes as a medium for transferring ions used in electrolyte membrane fuel cells, proton exchange membrane fuel cells, redox flow batteries, and water purification are being actively conducted.

Currently, a material widely used as an ion exchange membrane is a Nafion™-based membrane, a polymer containing a perfluorinated sulfonic acid group, manufactured by DuPont, USA. When this membrane has a saturated moisture content, it has ion conductivity of 0.08 S/cm at room temperature, excellent mechanical strength and chemical resistance, and has stable performance as an electrolyte membrane enough to be used in fuel cells for automobiles. In addition, commercially available membranes of a similar type include Aciplex-S membranes manufactured by Asahi Chemicals, Dow membranes manufactured by Dow Chemicals, and Asahi Glass Ltd. There are Flemion membranes and GoreSelect membranes from Gore & Associates, and polymers perfluorinated in alpha or beta form by Ballard Power System of Canada. It is under development research.

However, the membranes are expensive and difficult to synthesize, so there is a difficulty in mass production, and the efficiency as an ion exchange membrane is greatly reduced, such as having low ionic conductivity at high or low temperatures.

In addition, the membranes undergo a crossover phenomenon in which vanadium ions or bromine ions in addition to the hydronium ions to be transferred are transmitted during operation of the redox flow battery, and these ions cause a degradation reaction in the membranes or lower voltage efficiency. cause problems

It is an object of the present invention to provide an ion exchange membrane in which the movement of vanadium ions and bromine ions is suppressed and the structural stability is excellent.

Another object of the present invention is to provide a method for manufacturing the ion exchange membrane.

Another object of the present invention is to provide an energy storage device including the ion exchange membrane.

According to an embodiment of the present invention, it includes a support layer, a polymer electrolyte membrane positioned on one surface of the support layer and including an ion conductor, and an interfacial adhesive layer positioned between the support layer and the polymer electrolyte membrane, the interface The adhesive layer provides an ion exchange membrane that adheres the support layer and the polymer electrolyte membrane while any one selected from the group consisting of the support layer, the polymer electrolyte membrane, and both is melted and then solidified.

The interfacial adhesive layer may be one in which a portion of the polymer electrolyte membrane is melted and penetrated into the pores of the support layer and then solidified while bonding the support layer and the polymer electrolyte membrane.

The interfacial adhesive layer may be formed by bonding the support layer and the polymer electrolyte membrane while a part of the support layer is melted and attached to the polymer electrolyte membrane and then solidified.

The interfacial adhesive layer may be formed by bonding the support layer and the polymer electrolyte membrane while the support layer and the polymer electrolyte membrane are melted and mixed and then solidified.

The support layer is polybutylene, polypropylene, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyimide, polyurethane, polybutene, polylactic acid, polyvinyl alcohol, polyvinyl chloride, polyphenylene sulfide. , polysulfone, polyethylene-co-vinyl acetate, polyacrylonitrile, cyclic polyolefin, polyoxymethylene, polyolefin-based thermoplastic elastomer, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), their It may include any one selected from the group consisting of derivatives, copolymers thereof, and mixtures thereof.

The polymer electrolyte membrane is poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), a copolymer of tetrafluoroethylene and fluorovinyl ether containing a sulfonic acid group, defluorinated sulfided polyetherketone, sulfonated sulfonated polyimide (S-PI), sulfonated polyarylethersulfone (S-PAES), sulfonated polyetheretherketone (SPEEK), sulfonated polybenzimidazole (S-PAES) polybenzimidazole (SPBI), sulfonated polysulfone (S-PSU), sulfonated polystyrene (S-PS), sulfonated polyphosphazene, sulfonated polyquinoxaline ( sulfonated polyquinoxaline, sulfonated polyketone, sulfonated polyphenylene oxide, sulfonated polyether sulfone, sulfonated polyether ketone , sulfonated polyphenylene sulfone, sulfonated polyphenylene sulfide, sulfonated polyphenylene sulfide sulfone, sulfonated polyphenylene sulfide sulfone Sulfonated polyphenylene sulfide sulfone nitrile, sulfonated polyarylene ether, sulfonated polyarylene ether nitrile, sulfonated polyarylene ether nitrile ed polyarylene ether ether nitrile), polyarylene ether sulfone ketone (sulfonated polyarylene ether sulfone ketone), derivatives thereof, copolymers thereof, and mixtures thereof may include any one ion conductor selected from the group consisting of.

The polymer electrolyte membrane may include a porous support including a plurality of pores, and the ion conductor filling the pores of the porous support.

The volume ratio of the polymer electrolyte membrane and the support layer may be 1:0.1 to 1:2.0.

A difference in swelling ratio between the polymer electrolyte membrane and the support layer may be 10% or less.

The polymer electrolyte membrane may include inorganic particles substituted with ion exchange groups.

The polymer electrolyte membrane may include the inorganic particles substituted with the ion exchange group in an amount of 0.001 parts by weight to 0.5 parts by weight based on 100 parts by weight of the ion conductor.

According to another embodiment of the present invention, a polymer electrolyte membrane including an ion conductor is placed on one surface of a support layer, and any one selected from the group consisting of the support layer, the polymer electrolyte membrane, and both is melted and then solidified It provides a method of manufacturing an ion exchange membrane comprising the step of forming an interfacial adhesive layer for adhering the support layer and the polymer electrolyte membrane.

The interfacial adhesive layer may be to adhere the support layer and the polymer electrolyte membrane while a part of the polymer electrolyte membrane is melted and penetrated into the pores of the support layer and then solidified.

The interfacial adhesive layer may be one in which a portion of the support layer is melted and attached to the polymer electrolyte membrane and then solidified to adhere the support layer and the polymer electrolyte membrane.

The interfacial adhesive layer may be to adhere the support layer and the polymer electrolyte membrane while the support layer and the polymer electrolyte membrane are melted and mixed and then solidified.

The method of manufacturing the ion exchange membrane may further include preparing a polymer electrolyte membrane including inorganic particles substituted with ion exchange groups.

According to another embodiment of the present invention, there is provided an energy storage device including the ion exchange membrane.

The energy storage device may be a redox flow battery.

Since the ion exchange membrane of the present invention includes a support layer, the ion permeation path is increased and the movement of vanadium ions and bromine ions is suppressed, thereby causing deterioration of these ions in the polymer electrolyte membrane or lowering the voltage efficiency. While being prevented, the bonding force between the interface between the support layer and the polymer electrolyte membrane is high, and the difference between the swelling property of the support layer and the swelling property of the polymer electrolyte membrane is minimized, so that the structural stability is excellent.

1 is a cross-sectional view schematically showing an ion exchange membrane according to an embodiment of the present invention.
2 is a schematic diagram schematically showing an all-vanadium-based redox battery according to another embodiment of the present invention.

Hereinafter, the present invention will be described in more detail.

An ion exchange membrane according to an embodiment of the present invention includes a support layer, a polymer electrolyte membrane disposed on one surface of the support layer, and an ion conductor, and an interfacial adhesive layer positioned between the support layer and the polymer electrolyte membrane.

1 is a cross-sectional view schematically showing the ion exchange membrane according to an embodiment. Hereinafter, the ion exchange membrane will be described with reference to FIG. 1 .

The ion exchange membrane 104 is located between the support layer 10, the polymer electrolyte membrane 20 positioned on one surface of the support layer 10, and the support layer 10 and the polymer electrolyte membrane 20. and an interfacial adhesive layer 30 .

The support layer 10 prevents crossover of unwanted ions and serves to improve dimensional stability of the ion exchange membrane 104 . Specifically, the support layer 10 inhibits the movement of vanadium ions and bromine ions by increasing the permeation path of ions, thereby causing deterioration of these ions in the polymer electrolyte membrane 20 or lowering the voltage efficiency. can prevent

The support layer 10 has a plurality of pores therein and may be in various forms such as a material having excellent strength, for example, a woven fabric, a non-woven fabric, a mesh, a net, a sponge, a foam, a metal porous material, a metal mesh, polyester, It may be made of various materials such as polyamide, aramid resin, polyimide, fluororesin, ultra-high molecular weight polyethylene, and metal.

Specifically, if the support layer 10 is the nonwoven fabric composed of a plurality of randomly oriented fibers, the nonwoven fabric is interlaid, but not in the same manner as the woven fabric, but individual fibers or filaments. It means a sheet having the structure of The nonwoven fabric is carding (carding), garneting (garneting), air-laying (air-laying), wet-laying (wet-laying), melt blowing (melt blowing), spunbonding (spunbonding), thermal bonding (thermal bonding) ) and may be manufactured by any one method selected from the group consisting of stitch bonding.

The fibers constituting the nonwoven fabric may include one or more polymer materials, and may be used as long as they are generally used as polymer materials for fiber formation, and specifically, hydrocarbon-based fiber-forming polymer materials may be used. For example, the fiber-forming polymeric material may include polyolefins such as polybutylene, polypropylene and polyethylene; polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyamides (such as nylon-6 or nylon-6,6); polyimide; Polyurethane; polybutene; polylactic acid; polyvinyl alcohol; polyvinyl chloride; polyphenylene sulfide; polysulfone; fluid crystalline polymers; polyethylene-co-vinyl acetate; polyacrylonitrile; cyclic polyolefins; polyoxymethylene; polyolefin-based thermoplastic elastomers; polytetrafluoroethylene (PTFE); polyvinylidene fluoride (PVDF); derivatives thereof; copolymers thereof; and any one selected from the group consisting of mixtures thereof, but the present invention is not limited thereto.

The polymer electrolyte membrane 20 includes the ion conductor.

The ion conductor may be a cation conductor having a cation exchange group capable of transporting a cation such as a proton, or an anion conductor having an anion exchange group capable of transporting an anion such as a hydroxy ion, carbonate or bicarbonate.

The cation exchange group may be any one selected from the group consisting of a sulfonic acid group, a carboxyl group, a boronic acid group, a phosphoric acid group, an imide group, a sulfonimide group, a sulfonamide group, and combinations thereof, and generally a sulfonic acid group or a carboxyl group. have.

The cation conductor may include a fluorine-based polymer including the cation exchange group and including fluorine in a main chain; Benzimidazole, polyamide, polyamideimide, polyimide, polyacetal, polyethylene, polypropylene, acrylic resin, polyester, polysulfone, polyether, polyetherimide, polyester, polyethersulfone, polyetherimide, poly hydrocarbon-based polymers such as carbonate, polystyrene, polyphenylene sulfide, polyetheretherketone, polyetherketone, polyarylethersulfone, polyphosphazene, or polyphenylquinoxaline; partially fluorinated polymers such as polystyrene-graft-ethylenetetrafluoroethylene copolymer or polystyrene-graft-polytetrafluoroethylene copolymer; sulfone imides and the like.

More specifically, when the cation conductor is a hydrogen ion cation conductor, the polymer may include a cation exchange group selected from the group consisting of a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, a phosphonic acid group, and derivatives thereof in the side chain, Specific examples include poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), copolymers of tetrafluoroethylene and fluorovinyl ether containing sulfonic acid groups, defluorinated sulfided polyether ketones, derivatives thereof, fluorine-based polymers including copolymers thereof and mixtures thereof; Sulfonated polyimide (S-PI), sulfonated polyarylethersulfone (S-PAES), sulfonated polyetheretherketone (SPEEK), sulfonated polybenzimi Sulfonated polybenzimidazole (SPBI), sulfonated polysulfone (S-PSU), sulfonated polystyrene (S-PS), sulfonated polyphosphazene, sulfonated poly Sulfonated polyquinoxaline, sulfonated polyketone, sulfonated polyphenylene oxide, sulfonated polyether sulfone, sulfonated polyether ketone polyether ketone), sulfonated polyphenylene sulfone, sulfonated polyphenylene sulfide, sulfonated polyphenylene sulfide sulfone, sulfonated polyphenyl Sulfonated polyphenylene sulfide sulfone nitrile, sulfonated polyarylene ether, sulfonated polyarylene ether nitrile, sulfonated polyarylene ether nitrile ( sulfonated polyarylene ether ether nitrile), polyarylene ether sulfone ketone (sulfonated polyarylene ether sulfone ketone), derivatives thereof and hydrocarbon-based polymers including sieves, copolymers thereof, and mixtures thereof, but is not limited thereto.

The anion conductor is a polymer capable of transporting anions such as hydroxy ions, carbonate or bicarbonate, and the anion conductor is commercially available in the form of a hydroxide or halide (usually chloride), and the anion conductor is an industrial essence (water purification), metal separation or catalytic processes, and the like.

As the anion conductor, a polymer doped with a metal hydroxide may be generally used, and specifically, poly(ethersulfone) doped with a metal hydroxide, polystyrene, vinyl-based polymer, poly(vinyl chloride), poly(vinylidene fluoride) , poly(tetrafluoroethylene), poly(benzimidazole), or poly(ethylene glycol) may be used.

On the other hand, the polymer electrolyte membrane 20 may be in the form of a reinforced membrane in which the ion conductor fills the pores of a fluorine-based porous support such as e-PTFE or a porous support such as a porous nanoweb support manufactured by electrospinning, etc. have.

The interfacial adhesive layer 30 is positioned between the support layer 10 and the polymer electrolyte membrane 20 , and bonds the support layer 10 and the polymer electrolyte membrane 20 .

When the support layer 10 is introduced and physically coupled to the polymer electrolyte membrane 20 , there is a problem of low interfacial binding force. In addition, when the support layer 10 and the polymer electrolyte membrane 20 are adhered using an adhesive, detachment may occur due to dissolution of the adhesive, and it is difficult to have structural stability.

Therefore, in the present invention, the interfacial adhesive layer 30 is solidified after any one selected from the group consisting of the support layer 10, the polymer electrolyte membrane 20, and both of the support layer and the polymer The electrolyte membrane is adhered. For this reason, the ion exchange membrane 104 has a high bonding force between the interface between the support layer 10 and the polymer electrolyte membrane 20 , and minimizes the difference in swelling degree between the support layer 10 and the polymer electrolyte membrane 20 . Structural stability can be further improved.

Specifically, in one example, the interfacial adhesive layer 30 is formed with the support layer 10 and the polymer electrolyte while a part of the polymer electrolyte membrane 20 is melted and penetrated into the pores of the support layer 10 and then solidified. The film 20 may be adhered.

In this case, the polymer electrolyte membrane 20 may use one that can be melted by heat or an organic solvent among the ionic conductors exemplified above. For example, when the ion conductor is the fluorine-based polymer, it can be generally melted by heat, and when the ion conductor is the hydrocarbon-based polymer, it can be generally dissolved with a solvent. In this case, the support layer 10 may be exemplified by polyphenylene sulfide (PPS) having a higher melting temperature than that of the polymer electrolyte membrane 20 .

A portion of the polymer electrolyte membrane to be melted may be up to a certain depth from one surface of the polymer electrolyte membrane, and the predetermined depth is the thickness of the interfacial adhesive layer 30 to be formed and the porosity of the support layer 10. It can be adjusted according to the content of the ion conductor penetrating into the pores of the support layer 10 . On the other hand, after the entire polymer electrolyte membrane 20 is melted, only a part of it may penetrate into the pores of the support layer 10 .

In another example, the interfacial adhesive layer 30 includes the support layer 10 and the polymer electrolyte membrane 20 while a part of the support layer 10 is melted and attached to the polymer electrolyte membrane 20 and then solidified. may be bonded.

In this case, the support layer 10 may be made of a polymer having a lower melting temperature than the polymer electrolyte membrane 20, such as polyethylene or polypropylene.

Alternatively, the support layer 10 may be a thermal bonding nonwoven fabric. The thermal bonding nonwoven fabric comprises a first fiber made of high melting point polyethylene terephthalate (PET) and a second fiber made of low melting point polyethylene terephthalate (PET), and the first fiber and the second fiber are mixed and spun. can be manufactured. The high-melting-point polyethylene terephthalate (PET) may have a melting point of 240°C or higher, and the low-melting-point polyethylene terephthalate (PET) may have a melting point of 120°C to 230°C. In this case, the content of the first fiber is 10 wt% to 90 wt%, specifically 30 wt% to 70 wt%, and the content of the second fiber is 10 wt% to 90 wt% with respect to the total weight of the thermal bonding nonwoven fabric , specifically 30 wt% to 70 wt%.

At this time, a portion of the support layer to be melted may be up to a certain depth from one surface of the support layer, and the predetermined depth is based on the content of the melted support layer in consideration of the thickness of the interfacial adhesive layer 30 to be formed. can be adjusted accordingly.

In another example, the interfacial adhesive layer 30 is formed by melting and mixing the support layer 10 and the polymer electrolyte membrane 20 and solidifying the support layer 10 and the polymer electrolyte membrane 20. It may be adhesive. Accordingly, the interfacial adhesive layer 30 may be formed of a mixture of a polymer material constituting the support layer 10 and an ion conductor constituting the polymer electrolyte membrane 20 . At this time, the material of the support layer 10 and the polymer electrolyte membrane 20 is the same as described above, except that the temperature at which the support layer 10 and the polymer electrolyte membrane 20 can melt at the same time or higher during melt adhesion By applying heat, or using a solvent capable of dissolving the support layer 10 and the polymer electrolyte membrane 20 at the same time.

On the other hand, as described above, as the interfacial adhesive layer 30 is melt-bonded between the support layer 10 and the polymer electrolyte membrane 20, the support layer 10 and the polymer electrolyte membrane 20 Structural stability can be further improved by minimizing the difference in swelling degree of the ion exchange membrane 104 so that the difference in swelling degree between the support layer 10 and the polymer electrolyte membrane 20 itself is small. Stability can be further improved.

Specifically, the difference in swelling ratio between the polymer electrolyte membrane 20 and the support layer 10 may be 10% or less, and more specifically, 5% or less.

At this time, the swelling ratio of the polymer electrolyte membrane 20 and the support layer 10 is immersed in distilled water at 80° C. for 24 hours and then taken out and wet. The thickness and area are measured, and the thickness and area are measured after drying it in a vacuum at 80° C. for 24 hours. _{The thickness (T wet} ) and area (L _wet ) and the thickness (T _dry ) and area (L _dry ) in the wet state of the polymer electrolyte membrane 20 or the support layer 10 in the following Equation 1 and By substituting in Equation 2, it is possible to measure the swelling ratio to the thickness and the swelling ratio to the area.

[Equation 1]

(T _wet - T _dry / T _dry ) × 100 = △T(Swell ratio to thickness, %)

[Equation 2]

(L _wet - L _dry / L _dry ) × 100 = △L(Swell ratio to area, %)

The difference in the swelling ratio can be calculated by Equation 3 below. In this case, the swelling ratio of the polymer electrolyte membrane 20 and the support layer 10 may be a swelling ratio to a thickness, a swelling ratio to an area, or both.

[Equation 3]

Difference in swelling ratio (%) = swelling ratio of polymer electrolyte membrane - swelling ratio of support layer

When the difference in swelling ratio between the polymer electrolyte membrane 20 and the support layer 10 exceeds 10%, physical separation between the two layers may occur.

Meanwhile, in order to make the difference in the swelling ratio between the support layer 10 and the polymer electrolyte membrane 20 itself small, the polymer electrolyte membrane 20 may further include inorganic particles substituted with ion exchange groups.

The inorganic particles have structural stability while containing a large amount of moisture or solvent by including micropores that are structurally formed to contain a large amount of moisture. Accordingly, when the inorganic particles are introduced into the polymer electrolyte membrane 20, the difference in the swelling ratio can be made smaller by serving as a reservoir for storing the absorbed moisture or solvent, and the inorganic particles are separated from the ion exchange group. As substituted with , dimensional stability, durability, and dispersibility in the polymer electrolyte membrane 20 may be further improved.

Specifically, the inorganic particles are substituted with any one cation exchange group selected from the group consisting of a sulfonic acid group, a carboxyl group, a boronic acid group, a phosphoric acid group, an imide group, a phosphonic acid group, a sulfonimide group, a sulfonamide group, and combinations thereof. and may be preferably substituted with a sulfonic acid group or a carboxyl group.

The inorganic particles may be selected from the group consisting of ionic conductors, radical scavengers, oxygen evolution reaction (OER) catalysts, gas barrier particles, and mixtures thereof. can be one

The ion conductor not only makes the difference in the swelling ratio between the support layer 10 and the polymer electrolyte membrane 20 small, but also has excellent dispersibility in the polymer electrolyte membrane 20, so that the polymer electrolyte membrane 20 ) can improve the ionic conductivity. The ion conductor is a hydrophilic inorganic additive, specifically SnO ₂ , silica, alumina, zirconia, mica, zeolite, phosphotungstic acid, silicon It may be any one selected from the group consisting of tungstic acid (silicon tungstic acid), zirconium hydrogen phosphate (zirconiumhydrogen phosphate), and mixtures thereof.

The radical scavenger is an ion of a transition metal capable of inhibiting the generation of hydroxy radicals by decomposing hydrogen peroxide into water and oxygen, specifically, cerium, tungsten, ruthenium, palladium, silver, rhodium, cerium, zirconium, yttrium, and manganese. , molybdenum, lead, vanadium, titanium, and the like, and the metal itself, its ionic form, their oxide form, their salt form, or other forms are also possible.

The oxygen evolution reaction catalyst may include a platinum-based metal or a non-platinum-based metal active material. The platinum-based metal may be used alone or in combination of two or more selected from the group consisting of platinum, gold, palladium, rhodium, iridium, ruthenium, osmium, platinum alloys, alloys thereof, and mixtures thereof.

The gas barrier particles include clay, montmorillonite, saponite, laponite, mica, fluorohetorite, kaolinite, vermiculite. And it may be any one selected from the group consisting of mixtures thereof.

The polymer electrolyte membrane 20 may include 0.001 parts by weight to 0.5 parts by weight of the inorganic particles substituted with the ion exchange group based on 100 parts by weight of the ion conductor, and more specifically, 0.05 to 0.2 parts by weight. can do. If the content of the inorganic particles substituted with the ion exchange group is less than 0.001 parts by weight based on 100 parts by weight of the ion conductor, it may be difficult to express the effect of improving the swelling property due to the introduction of the inorganic particles, and when it exceeds 0.5 parts by weight, the polymer electrolyte It is difficult to form the film 20 and mechanical properties may be deteriorated.

The volume ratio of the polymer electrolyte membrane 20 and the support layer 10 may be 1:0.1 to 1:2.0, and more specifically, 1:0.5 to 1:0.10. When the volume ratio of the support layer 10 is less than 0.1 with respect to the volume ratio 1 of the polymer electrolyte membrane 20, the swelling property of the polymer electrolyte membrane 20 itself is greatly expressed, and the effect of introducing the support layer 10 is insignificant. If it exceeds 2.0, the support layer 10 may act as a resistance to the material to be transferred by the polymer electrolyte membrane 20 .

In addition, the volume ratio of the polymer electrolyte membrane 20 and the interfacial adhesive layer 30 may be 1:0.001 to 1:0.2, and more specifically, 1:0.005 to 1:0.01. If the volume ratio of the interfacial adhesive layer 30 is less than 0.001 with respect to the volume ratio 1 of the polymer electrolyte membrane 20, desorption of the interface may occur, and if it exceeds 0.2, the proton transfer efficiency may decrease due to the resistance occurring at the interface. can

In the method for manufacturing an ion exchange membrane according to another embodiment of the present invention, a polymer electrolyte membrane including an ion conductor is placed on one surface of a support layer, and any one selected from the group consisting of the support layer, the polymer electrolyte membrane, and both and forming an interfacial adhesive layer for adhering the support layer and the polymer electrolyte membrane while melting and solidifying.

Specifically, in one example, the interfacial adhesive layer may adhere the support layer and the polymer electrolyte membrane while a part of the polymer electrolyte membrane is melted and penetrated into the pores of the support layer and then solidified.

In this case, the polymer electrolyte membrane may be thermally melted at a temperature greater than or equal to the melting point of the ion conductor constituting the polymer electrolyte membrane. The thermal melting temperature may be 80 °C to 250 °C, and more specifically, 90 °C to 230 °C. If the thermal melting temperature is less than 80 °C, the bonding between the polymer electrolyte membrane and the support layer may be non-uniform, and if it exceeds 250 °C, damage to the polymer electrolyte membrane and the support layer may occur.

On the other hand, when the polymer electrolyte membrane is dissolved using an organic solvent, as an organic solvent capable of dissolving the polymer electrolyte membrane, N-methyl-2-pyrrolidine (NMP), dimethyl Any one selected from the group consisting of formamide (dimethylformamide, DMF), dimethylacetamide (DMA), dimethylsulfoxide (DMSO), and combinations thereof may be used. In this case, the organic solvent may be applied to the surface of the polymer electrolyte membrane using a spray or the like to dissolve the surface of the polymer electrolyte membrane.

In addition, the molten ion conductor may allow itself to permeate into the pores of the support layer by gravity, but may also apply a certain pressure to make the permeation more efficient. The pressure may be 0.1 bar to 5 bar, and more specifically, 1 bar to 3 bar. When the pressure is less than 0.1 bar, it is difficult to expect the effect of pressurization, and when it exceeds 5 bar, damage to the support layer may occur or the penetration may be non-uniform due to the high pressure.

In another example, the interfacial adhesive layer may adhere the support layer and the polymer electrolyte membrane while a part of the support layer is melted and attached to the polymer electrolyte membrane and then solidified.

In this case, the support layer may be made of a polymer having a lower melting temperature than the polymer electrolyte membrane, such as polyethylene or polypropylene. The thermal melting temperature of the support layer may be 80 °C to 150 °C, and more specifically, 90 °C to 140 °C. If the thermal melting temperature is less than 80 °C, the bonding between the two interfaces may be non-uniform, and if it exceeds 150 °C, damage to the support layer may occur.

Alternatively, the support layer may be a thermal bonding nonwoven fabric. In this case, the thermal bonding nonwoven fabric may be thermally melted at a temperature between the melting points of the first fiber and the second fiber.

In addition, the molten support layer may be attached to the polymer electrolyte membrane by itself, but a certain pressure may be applied so that the molten support layer is compressed to the polymer electrolyte membrane in order to further improve adhesion. The pressure may be 0.1 bar to 5 bar, and more specifically, 1 bar to 3 bar. When the pressure is less than 0.1 bar, it is difficult to describe the effect of the pressure, the bonding surface may be non-uniform, and if it exceeds 5 bar, damage to the support layer may occur.

In another example, the interfacial adhesive layer may adhere the support layer and the polymer electrolyte membrane while the support layer and the polymer electrolyte membrane are melted and mixed and then solidified.

In this case, the polymer electrolyte membrane and the support layer may be thermally melted, and the thermal melting temperature may be 80°C to 250°C, and more specifically, 90°C to 230°C. When the thermal melting temperature is less than 80 °C, the adhesive surface between the polymer electrolyte membrane and the support layer may be non-uniform, and when it exceeds 250 °C, damage to the polymer electrolyte membrane and the support layer may occur.

In addition, a certain pressure may be applied so that the molten polymer electrolyte membrane and the molten support layer are well mixed with each other to form the surfactant layer. The pressure may be 0.1 bar to 5 bar, and more specifically, 1 bar to 3 bar. If the pressure is less than 0.1 bar, the adhesive surface may be non-uniform, and if it exceeds 5 bar, damage may occur to the polymer electrolyte membrane and the support layer.

On the other hand, the method of manufacturing the ion exchange membrane may further include the step of preparing a polymer electrolyte membrane including inorganic particles substituted with the ion exchange group so that the difference in the swelling ratio between the support layer and the polymer electrolyte membrane itself is small. can

The step of preparing the polymer electrolyte membrane including the inorganic particles substituted with the ion exchange group is specifically, the step of replacing the surface of the inorganic particles with an ion exchange group, mixing the inorganic particles substituted with the ion exchange group with the ion conductor to prepare a composition for forming a polymer electrolyte membrane, and preparing the polymer electrolyte membrane using the composition for forming a polymer electrolyte membrane.

Regarding the method of substituting the inorganic particle with an ion exchange group, for example, if the ion exchange group is a sulfonic acid group that is a cation exchange group, the inorganic particles are sulfonated using a sulfonating agent. Ion exchange groups can be introduced into the particle.

Sulfuric acid may be used as the sulfonating agent, but as another example, the prepared polymer is mixed with dichloromethane, chloroform, 1,2-dichloroethane (1) in the presence of an excess of chlorosulfonic acid. Inorganic particles substituted with hydrogen ion conducting groups can be prepared by conducting the reaction in a chlorinated solvent such as ,2-dichloroethane).

Next, a composition for forming a polymer electrolyte membrane is prepared by mixing the inorganic particles substituted with the ion exchange group and the ion conductor.

The composition for forming a polymer electrolyte membrane may include the ion conductor in a concentration of 0.1% to 30%, and may include the ion conductor in a concentration of 1% to 10%. In the specification of the present invention, the concentration means a percent concentration, and the percent concentration can be obtained as a percentage of the mass of the solute with respect to the mass of the solution.

In this case, the amount of the inorganic particles substituted with the ion exchange group is the amount of the inorganic particles substituted with the ion exchange group in 100 parts by weight of the ion conductor in the polymer electrolyte membrane prepared using the composition for forming a polymer electrolyte membrane. It may be appropriately adjusted to be 0.001 parts by weight to 0.5 parts by weight, more specifically 0.05 parts by weight to 0.2 parts by weight.

As the solvent, alcohol such as ethanol, isopropyl alcohol, n-propyl alcohol, butyl alcohol, water, dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, etc. may be preferably used.

The polymer electrolyte membrane may be manufactured by a general film forming method using the composition for forming a polymer electrolyte membrane, for example, may be formed by applying the composition for forming a polymer electrolyte membrane to a substrate and drying the composition. As a method of applying the composition for forming the polymer electrolyte membrane, a method such as slot die coating, bar coating, comma coating, screen printing, spray coating, doctor blade coating, or a brush may be used.

The drying process may be drying at 25 °C to 90 °C for 12 hours or more. If the drying temperature is less than 25 ℃ and the drying time is less than 12 hours, a sufficiently dried polymer electrolyte membrane may not be formed, and if it is dried at a temperature exceeding 90 ℃, cracks may occur in the polymer electrolyte membrane.

The energy storage device according to another embodiment of the present invention includes the ion exchange membrane. Hereinafter, a case in which the energy storage device is a redox flow battery will be described in detail, but the present invention is not limited thereto, and the ion exchange membrane may be applied to an energy storage device in the form of a fuel cell or a secondary battery.

In one example of the energy storage device, the ion exchange membrane has low vanadium ion permeability by blocking vanadium ions, etc., so that when applied to a vanadium redox flow battery, the vanadium active material crosses over to improve energy efficiency. Since high energy efficiency can be achieved by solving the degradation problem, the energy storage device may preferably be a redox flow battery.

The redox flow battery may be charged and discharged by supplying a positive electrolyte and a negative electrolyte to a battery cell including a positive electrode and a negative electrode disposed to face each other and the ion exchange membrane disposed between the positive electrode and the negative electrode.

The redox flow battery is an all-vanadium-based redox battery using a V(IV)/V(V) redox couple as a positive electrolyte and a V(II)/V(III) redox couple as a negative electrolyte; a vanadium-based redox battery using a halogen redox couple as a positive electrolyte and a V(II)/V(III) redox couple as a negative electrolyte; a polysulfide bromine redox battery using a halogen redox couple as a positive electrolyte and a sulfide redox couple as a negative electrolyte; Or it may be a zinc-bromine (Zn-Br) redox battery using a halogen redox couple as a positive electrolyte and a zinc (Zn) redox couple as a negative electrolyte, but in the present invention, the type of the redox flow battery is not limited

Hereinafter, a case in which the redox flow battery is an all-vanadium-based redox battery will be described as an example. However, the redox flow battery of the present invention is not limited to the all-vanadium-based redox battery.

2 is a schematic diagram schematically showing the all-vanadium-based redox battery.

Referring to FIG. 2, the redox flow battery includes a cell housing 102, the ion exchange membrane 104 installed to divide the cell housing 102 into an anode cell 102A and a cathode cell 102B, and the an anode 106 and a cathode 108 positioned in anode cell 102A and cathode cell 102B, respectively.

In addition, the redox flow battery may further include a positive electrolyte storage tank 110 in which the positive electrolyte is stored and a negative electrolyte storage tank 112 in which the negative electrolyte is stored.

In addition, the redox flow battery includes an anode electrolyte inlet and a cathode electrolyte outlet at the top and bottom of the cathode cell 102A, and a cathode electrolyte inlet and a cathode electrolyte outlet at the top and bottom of the cathode cell 102B can do.

The positive electrolyte stored in the positive electrolyte storage tank 110 is introduced into the positive electrode cell 102A through the positive electrolyte inlet by the pump 114, and then from the positive electrode cell 102A through the positive electrolyte outlet. discharged

Similarly, the negative electrolyte stored in the negative electrolyte storage tank 112 is introduced into the negative electrode cell 102B through the negative electrolyte inlet by the pump 116, and then the negative electrode cell 102B through the negative electrolyte outlet. ) is emitted from

In the anode cell 102A, the movement of electrons through the anode 106 occurs according to the operation of the power source/load 118, and accordingly, an oxidation/reduction reaction of ^{V 5+} ↔V ^{4+ occurs.} Similarly, in the cathode cell 102B, the movement of electrons through the cathode 108 occurs according to the operation of the power source/load 118, and thus an oxidation/reduction reaction of ^{V 2+} ↔V ^{3+ occurs.} After the oxidation/reduction reaction, the positive electrolyte and the negative electrolyte are circulated to the positive electrolyte storage tank 110 and the negative electrolyte storage tank 112 , respectively.

The anode 106 and the cathode 108 are formed of Ru, Ti, Ir. A composite comprising an oxide of one or more metals selected from Mn, Pd, Au and Pt and one or more metals selected from Ru, Ti, Ir, Mn, Pd, Au and Pt (for example, on a Ti substrate Ir oxide or Ru oxide coated), a carbon composite including the composite material, a dimensionally stable electrode (DSE) including the composite material, a conductive polymer (for example, polyacetylene, polythiophene, etc. conducting electricity) material), graphite, glassy carbon, conductive diamond, conductive DLC (Diamond-Like Carbon), non-woven fabric made of carbon fiber, and woven fabric made of carbon fiber.

The positive electrolyte and the negative electrolyte may include any one metal ion selected from the group consisting of titanium ions, vanadium ions, chromium ions, zinc ions, tin ions, and mixtures thereof.

For example, the negative electrolyte includes a vanadium divalent ion (V ²⁺ ) or a vanadium trivalent ion (V ³⁺ ) as a negative electrolyte ion, and the positive electrode electrolyte includes a vanadium tetravalent ion (V ^{4 ) as a positive electrolyte ion. +} ) or a vanadium ^pentavalent ion (V 5+ ).

The concentration of the metal ions included in the positive electrolyte and the negative electrolyte is preferably 0.3 M to 5 M.

As a solvent of the positive electrolyte and the negative electrolyte, H ₂ SO ₄ , K ₂ SO ₄ , Na ₂ SO ₄ , H ₃ PO ₄ , H ₄ P ₂ O ₇ , K ₂ PO ₄ , Na ₃ PO ₄ , K ₃ PO ₄ , HNO ₃ , KNO ₃ and NaNO ₃ Any one selected from the group consisting of may be used. Since all of the metal ions serving as the positive and negative active materials are water-soluble, aqueous solutions may be suitably used as solvents for the positive and negative electrolytes. In particular, when any one selected from the group consisting of sulfuric acid, phosphoric acid, nitric acid, sulfate, phosphate and nitrate is used as the aqueous solution, stability, reactivity and solubility of the metal ion may be improved.

On the other hand, the ion exchange membrane may also be applied to a membrane-electrode assembly for a fuel cell, and specifically, the membrane-electrode assembly includes an anode electrode and a cathode electrode positioned opposite to each other, and the ions positioned between the anode electrode and the cathode electrode It may include an exchange membrane.

Hereinafter, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein.

[Preparation Example: Preparation of Ion Exchange Membrane]

(Example 1)

A composition for forming a polymer electrolyte membrane was prepared by mixing 5% by weight of fluorine-based ionomer poly(perfluorosulfonic acid) (PFSA) having an EW of 725 g/eq and a H ₂ O/2-propanol solution with the remaining weight, followed by film formation. A 50 μm thick polymer electrolyte membrane was prepared.

The prepared polymer electrolyte membrane is placed on a polyphenylene sulfide (PPS) nonwoven fabric, and a pressure of 1.0 bar is applied at 130 ° C., which is a temperature higher than the melting initiation temperature of the poly (perfluorosulfonic acid) using a hot press, and the melt The polymer electrolyte membrane infiltrated into the pores of the support layer and then solidified to form an interfacial adhesive layer having a thickness of 2.5 μm.

In this case, the volume ratio of the polymer electrolyte membrane, the support layer, and the interfacial adhesive layer was 1:0.05:0.3.

(Example 2)

A composition for forming a polymer electrolyte membrane was prepared by mixing 5% by weight of fluorine-based ionomer poly(perfluorosulfonic acid) (PFSA) having an EW of 725 g/eq and a H ₂ O/2-propanol solution with the remaining weight, followed by film formation. A 50 μm thick polymer electrolyte membrane was prepared.

The prepared polymer electrolyte membrane is placed on a polyethylene (PE) nonwoven fabric, and a pressure of 1.0 bar is applied at 100° C. or higher, which is a temperature higher than the melting initiation temperature of the polyethylene (PE) nonwoven fabric, using a hot press, so that one side of the molten support layer The surface was pressed to the polymer electrolyte membrane and then solidified to form an interfacial adhesive layer having a thickness of 2.5 μm.

In this case, the volume ratio of the polymer electrolyte membrane, the support layer, and the interfacial adhesive layer was 1:0.05:0.3.

(Example 3)

A composition for forming a polymer electrolyte membrane was prepared by mixing 5% by weight of fluorine-based ionomer poly(perfluorosulfonic acid) (PFSA) having an EW of 725 g/eq and a H ₂ O/2-propanol solution with the remaining weight, followed by film formation. A 50 μm thick polymer electrolyte membrane was prepared.

On the other hand, a thermal bond nonwoven fabric in which general PET and low melting point PET were mixed in a weight ratio of 50:50 was prepared as a support layer.

The prepared polymer electrolyte membrane is placed on a polyethylene (PE) nonwoven fabric, and a pressure of 1.0 bar is applied at 140° C. or higher, which is a temperature higher than the thermal bonding temperature of the thermal bonding nonwoven fabric, using a hot press, and one surface of the molten support layer is applied. After pressing on the polymer electrolyte membrane, it was solidified to form an interfacial adhesive layer having a thickness of 5 μm.

In this case, the volume ratio of the polymer electrolyte membrane, the support layer, and the interfacial adhesive layer was 1:0.1:0.3.

(Example 4)

5 wt% of fluorine-based ionomer poly(perfluorosulfonic acid) (PFSA) having an EW of 725 g/eq, 10 wt% _{of SiO 2 inorganic particles substituted with a sulfonic acid group, and H 2} O/2-propanol solution with the remaining weight A composition for forming a polymer electrolyte membrane was prepared by mixing, and then a film was formed to prepare a polymer electrolyte membrane having a thickness of 50 μm.

The prepared polymer electrolyte membrane is placed on a polyphenylene sulfide (PPS) nonwoven fabric, and a pressure of 1.0 bar is applied at 130° C., which is a temperature higher than the melting initiation temperature of the poly (perfluorosulfonic acid) using a hot press, and the melt The polymer electrolyte membrane was solidified after penetrating into the pores of the support layer to form an interfacial adhesive layer with a thickness of 0.25 μm.

In this case, the volume ratio of the polymer electrolyte membrane, the support layer, and the interfacial adhesive layer was 1:0.05:0.3.

(Comparative Example 1)

A composition for forming a polymer electrolyte membrane was prepared by mixing 5% by weight of fluorine-based ionomer poly(perfluorosulfonic acid) (PFSA) having an EW of 725 g/eq and a H ₂ O/2-propanol solution with the remaining weight, followed by film formation. A 50 μm thick polymer electrolyte membrane was prepared.

(Comparative Example 2)

A composition for forming a polymer electrolyte membrane was prepared by mixing 5% by weight of fluorine-based ionomer poly(perfluorosulfonic acid) (PFSA) having an EW of 725 g/eq and a H ₂ O/2-propanol solution with the remaining weight, followed by film formation. A 50 μm thick polymer electrolyte membrane was prepared.

The prepared polymer electrolyte membrane and polyphenylene sulfide (PPS) nonwoven fabric were laminated with a polyurethane-based moisture-curing hot melt adhesive using a gravure coater, and for moisture curing of the adhesive, in an aging room at 35° C. and 85% humidity for 24 hours. matured.

In this case, the volume ratio of the polymer electrolyte membrane, the support layer, and the adhesive layer was 1:0.1:0.3.

(Comparative Example 3)

5 wt% of fluorine-based ionomer poly(perfluorosulfonic acid) (PFSA) having an EW of 725 g/eq, 10 wt% _{of SiO 2 inorganic particles substituted with a sulfonic acid group, and H 2} O/2-propanol solution with the remaining weight A composition for forming a polymer electrolyte membrane was prepared by mixing, and then a film was formed to prepare a polymer electrolyte membrane having a thickness of 50 μm.

The prepared polymer electrolyte membrane and polyphenylene sulfide (PPS) nonwoven fabric were laminated with a polyurethane-based moisture-curing hot melt adhesive using a gravure coater, and for moisture curing of the adhesive, in an aging room at 35° C. and 85% humidity for 24 hours. matured.

In this case, the volume ratio of the polymer electrolyte membrane, the support layer, and the adhesive layer was 1:0.1:0.3.

[Experimental Example 1: Analysis of Vanadium Permeability of the Prepared Ion Exchange Membrane]

Vanadium permeability was measured for the ion exchange membranes prepared in Examples and Comparative Examples, and the results are shown in Table 1 below.

The vanadium permeability was measured by UV-vis spectroscopy of the amount of vanadium ions transmitted over time by placing the membrane between the _{MgSO 4 solution and the vanadium solution.}

Vanadium permeability (cm ² /min) Example 1 4.5×10 ^-8 Example 2 2.5×10 ^-8 Example 3 3.7×10 ^-8 Example 4 1.4×10 ^-8 Comparative Example 1 1.6×10 ^-7 Comparative Example 2 8.3×10 ^-8 Comparative Example 3 6.2×10 ^-8

Referring to Table 1, it can be seen that in the case of the ion exchange membranes prepared in the Examples, permeation of vanadium pentavalent ions is prevented by including the support layer, compared to the ion exchange membranes prepared in Comparative Examples. have.

[Experimental Example 2: Measurement of dimensional stability of the prepared ion exchange membrane]

For the ion exchange membranes prepared in Examples and Comparative Examples, dimensional stability was measured at 80 ° C., at a relative humidity of 95%, and at 80 ° C., at a relative humidity of 50%, and the results are shown in Table 2 below.

The dimensional stability is determined by immersing the prepared ion exchange membrane in distilled water at 80° C. for 24 hours, taking out the wet polymer electrolyte membrane, measuring the thickness and area, and drying the ion exchange membrane in a vacuum at 80° C. for 24 hours. After measuring the thickness and area, the thickness (T _wet ) and area (L _wet ) and the thickness (T _dry ) and area (L _dry ) in the wet state of the polymer electrolyte membrane are substituted into the following Equations 1 and 2 Thus, the swelling ratio to the thickness and the swelling ratio to the area were measured.

[Equation 1]

(T _wet - T _dry / T _dry ) × 100 = △T(Swell ratio to thickness, %)

[Equation 2]

(L _wet - L _dry / L _dry ) × 100 = △L(Swell ratio to area, %)

Polymer electrolyte membrane swelling ratio (%) ¹⁾ Swelling ratio of support layer (%) ¹⁾ Difference in swelling ratio (%) ¹⁾ Dimensional stability (%) Δ L ΔT Example 1 10 2 8 2 18 Example 2 10 4 6 4 17 Example 3 10 5 5 5 16 Example 4 6 2 4 2 12 Comparative Example 1 10 - - 10 25 Comparative Example 2 10 2 8 8 20 Comparative Example 3 6 2 4 4 18

1) The swelling ratio of the polymer electrolyte membrane and the support layer is the result of measuring the swelling ratio with respect to the area according to Equation 2 above.

As shown in Table 2, the ion exchange membrane prepared in the above Example has a high bonding force between the interface between the support layer and the polymer electrolyte membrane, and the difference between the swelling property of the support layer and the swelling property of the polymer electrolyte membrane is minimized, so that the structural stability is excellent. it can be seen that

In particular, in the ion exchange membrane prepared in Example 4, as the polymer electrolyte membrane includes the inorganic particles substituted with the ion exchange groups, the difference in the swelling ratio between the support layer and the polymer electrolyte membrane itself becomes smaller, so that dimensional stability It can be seen that this is further improved.

On the other hand, in the ion exchange membranes prepared in Comparative Examples 2 and 3, as the support layer and the polymer electrolyte membrane are adhered by an adhesive, desorption may occur due to dissolution of the adhesive, thereby reducing dimensional stability and the like. It can be seen that structural stability is reduced.

[Experimental Example 3: Performance analysis of the prepared ion exchange membrane]

Voltage efficiency, current efficiency, and system efficiency were measured for the ion exchange membranes prepared in Examples and Comparative Examples, and the results are shown in Table 3 below.

The system efficiency (EE, Energy Efficiency) of the ion exchange membrane was measured by constructing the following device and measuring its electrochemical properties.

The device for measuring the energy efficiency consisted ^{of a unit cell having an electrode area of 25 cm 2} , two aqueous solution tanks, and a pump for measuring electrochemical properties in VRFB. As the anolyte, a solution containing 30 mL of 1.7 M VOSO ₄ and 2.5 MH ₂ SO ₄ (aqueous tetravalent vanadium solution) was used, and as the catholyte, an aqueous solution obtained by electrolytic reduction of the anolyte (trivalent vanadium aqueous solution) was used. The anolyte was used in a slightly larger amount than the catholyte to suppress overcharging. The measurement unit cell was composed of a film to be measured, a heat treated carbon felt (Heat treated Carbon Felt, manufactured by Nippon Carbon, Inc.) having a size of ^{25 cm 2 , and a current collector.} A potentiostat/constant current device was used for charging/discharging the unit cell for measurement, and the charge/discharge current density was measured at ^{60 mA/cm 2 .} In addition, the charging/discharging of the unit cell was performed in a cur-off method by setting the charging 1.6 V and the discharging 1.0 V, and charging/discharging was performed 5 times, using Equation 4 below to determine current efficiency (CE) and voltage efficiency. (VE) and energy efficiency (EE) were calculated.

[Equation 4]

CE=Q _D /Q _C

VE=E _AD /E _AC

EE=CE×VE

Here, Q _C [C] and Q _D [C] are the coulombic amounts during charging and discharging, and E _AC [V] and E _AD [V] are the cell voltages during charging and discharging.

voltage efficiency
(VE) current efficiency
(CE) system efficiency
(EE) Example 1 84.5 96.3 81.4 Example 2 83.7 96.5 80.8 Example 3 84.1 96.2 80.9 Example 4 85.4 97.5 83.3 Comparative Example 1 81.0 96.0 77.8 Comparative Example 2 82.6 94.3 77.9 Comparative Example 3 83.2 96.7 80.5

Referring to Table 3, in the case of the ion exchange membranes prepared in the Examples, compared to the ion exchange membranes prepared in Comparative Examples, the movement of vanadium ions and bromine ions is suppressed and the structural stability is improved, so that the voltage efficiency It can be confirmed that this is improved and deterioration is prevented.

Although the preferred embodiment of the present invention has been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also provided. is within the scope of the

10: support layer
20: polymer electrolyte membrane
30: interfacial adhesive layer
102: cell housing
102A: positive cell 102B: negative cell
104: ion exchange membrane
106: positive electrode
108: cathode
110: anode electrolyte storage tank
112: negative electrolyte storage tank
114, 116: pump
118: power / load

Claims (18)

support layer for preventing ionic crossover;
a reinforcing film located on one surface of the support layer, and
An interfacial adhesive layer positioned between the support layer and the reinforcing film,
The interfacial adhesive layer is to adhere the support layer and the reinforcing film while any one selected from the group consisting of the support layer, the reinforcing film, and both is melted and then solidified,
The support layer has the form of a woven fabric, non-woven fabric, mesh, net, sponge, or foam, polybutylene, polypropylene, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyimide, polyurethane, Polybutene, polylactic acid, polyvinyl alcohol, polyvinyl chloride, polyphenylene sulfide, polysulfone, polyethylene-co-vinyl acetate, polyacrylonitrile, cyclic polyolefin, polyoxymethylene, polyolefin-based thermoplastic elastomer, polytetra containing any one selected from the group consisting of fluoroethylene (PTFE), polyvinylidene fluoride (PVDF), derivatives thereof, copolymers thereof, and mixtures thereof,
The reinforcing membrane comprises a porous support including a plurality of pores and an ion conductor filling the pores of the porous support,
ion exchange membrane. The method of claim 1,
The interfacial adhesive layer is an ion exchange membrane wherein a portion of the reinforcement membrane is melted and penetrated into the pores of the support layer and then solidified while adhering the support layer and the reinforcement membrane. The method of claim 1,
The interfacial adhesive layer is an ion exchange membrane wherein a portion of the support layer is melted and adhered to the reinforcement film and then solidified while bonding the support layer and the reinforcement film. The method of claim 1,
The interfacial adhesive layer is an ion exchange membrane wherein the support layer and the reinforcing membrane are melted and mixed and then solidified while adhering the support layer and the reinforcing membrane. delete The method of claim 1,
The ion conductor is poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), a copolymer of tetrafluoroethylene and fluorovinyl ether containing a sulfonic acid group, defluorinated sulfided polyetherketone, sulfonated sulfonated polyimide (S-PI), sulfonated polyarylethersulfone (S-PAES), sulfonated polyetheretherketone (SPEEK), sulfonated polybenzimidazole (S-PAES) polybenzimidazole (SPBI), sulfonated polysulfone (S-PSU), sulfonated polystyrene (S-PS), sulfonated polyphosphazene, sulfonated polyquinoxaline ( sulfonated polyquinoxaline, sulfonated polyketone, sulfonated polyphenylene oxide, sulfonated polyether sulfone, sulfonated polyether ketone , sulfonated polyphenylene sulfone, sulfonated polyphenylene sulfide, sulfonated polyphenylene sulfide sulfone, sulfonated polyphenylene sulfide sulfone Sulfonated polyphenylene sulfide sulfone nitrile, sulfonated polyarylene ether, sulfonated polyarylene ether nitrile, sulfonated polyarylene ether nitrile Any one selected from the group consisting of polyarylene ether ether nitrile), polyarylene ether sulfone ketone (sulfonated polyarylene ether sulfone ketone), derivatives thereof, copolymers thereof, and mixtures thereof, the ion exchange membrane. delete The method of claim 1,
The volume ratio of the reinforcement membrane and the support layer is 1:0.1 to 1:2.0 of the ion exchange membrane. The method of claim 1,
The difference in swelling ratio between the reinforcement membrane and the support layer is 10% or less of the ion exchange membrane. 10. The method of claim 9,
The reinforcing membrane is an ion exchange membrane further comprising inorganic particles substituted with ion exchange groups. 11. The method of claim 10,
The reinforcing membrane is an ion exchange membrane comprising 0.001 parts by weight to 0.5 parts by weight of the inorganic particles substituted with the ion exchange group based on 100 parts by weight of the ion conductor. Positioning the reinforcing membrane on one side of the support layer for preventing ion crossover,
While solidifying after melting any one selected from the group consisting of the support layer, the reinforcing film, and both,
Comprising the step of forming an interfacial adhesive layer for adhering the support layer and the reinforcing film,
The support layer has the form of a woven fabric, non-woven fabric, mesh, net, sponge, or foam, polybutylene, polypropylene, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyimide, polyurethane, Polybutene, polylactic acid, polyvinyl alcohol, polyvinyl chloride, polyphenylene sulfide, polysulfone, polyethylene-co-vinyl acetate, polyacrylonitrile, cyclic polyolefin, polyoxymethylene, polyolefin-based thermoplastic elastomer, polytetra containing any one selected from the group consisting of fluoroethylene (PTFE), polyvinylidene fluoride (PVDF), derivatives thereof, copolymers thereof, and mixtures thereof,
The reinforcing membrane comprises a porous support including a plurality of pores and an ion conductor filling the pores of the porous support,
A method for manufacturing an ion exchange membrane. 13. The method of claim 12,
The interfacial adhesive layer is a method of manufacturing an ion exchange membrane that a part of the reinforcing membrane is melted and penetrated into the pores of the support layer and then solidified while adhering the support layer and the reinforcing membrane. 13. The method of claim 12,
The interfacial adhesive layer is a method of manufacturing an ion exchange membrane to which a part of the support layer is melted and attached to the reinforcement membrane and then solidified to adhere the support layer and the reinforcement membrane. 13. The method of claim 12,
The interfacial adhesive layer is a method of manufacturing an ion exchange membrane that adheres the support layer and the reinforcing membrane while the support layer and the reinforcing membrane are melted and mixed and then solidified. 13. The method of claim 12,
The reinforcing membrane further comprises inorganic particles substituted with an ion exchange group, the method of manufacturing an ion exchange membrane. An energy storage device comprising the ion exchange membrane according to claim 1 . 18. The method of claim 17,
The energy storage device is an energy storage device that is a redox flow battery (redox flow battery).

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