Hollow fiber membrane for fuel cell humidifier, and humidifier and fuel cell system comprising same

Abstract

The present invention relates to: a hollow fiber membrane for a fuel cell humidifier, the hollow fiber membrane comprising a polymer and an antioxidant, wherein the antioxidant is disposed on the inner surface and / or the outer surface thereof; a method for manufacturing same; and a humidifier and a fuel cell system, comprising same.

Description

Hollow fiber membrane for fuel cell humidifier, humidifier and fuel cell system including same

[0001] The present invention relates to a new hollow fiber membrane for a fuel cell humidifier and a humidifier and fuel cell system including the same.

[0002] Fuel cells are power-generating cells that convert the chemical energy of hydrogen and oxygen into electrical energy through an electrochemical reaction. Unlike conventional chemical cells like batteries or accumulators, fuel cells can continuously produce electricity as long as hydrogen and oxygen are supplied. They also have the advantage of no heat loss, making them more than twice as efficient as internal combustion engines.

[0003] Furthermore, fuel cells are environmentally friendly energy generators that generate no pollutants, as they use hydrogen and oxygen as raw materials and produce water as a product. Therefore, fuel cells are not only environmentally friendly but also offer the advantage of reducing concerns about resource depletion due to increased energy consumption.

[0004] Fuel cells can be classified into polymer electrolyte membrane fuel cells (PEMFC), phosphoric acid fuel cells (PAFC), molten carbonate fuel cells (MCFC), solid oxide fuel cells (SOFC), and alkaline fuel cells (AFC).

[0005] Among these, polymer electrolyte fuel cells are known to be suitable for use in transportation systems because they can operate at lower temperatures and have a higher power density than other fuel cells.

[0006] Meanwhile, polymer electrolyte fuel cells generally form water by reacting 2 moles of hydrogen and 1 mole of oxygen in the fuel cell stack during operation. However, if the reaction is incomplete, peroxide or hydroxyl radicals may be formed as byproducts.

[0007] The peroxide or hydroxyl radicals generated in this way cause deterioration of the polymer electrolyte membrane in the fuel cell stack, and a technology has been reported to include a small amount of additive, such as an inorganic material, in the polymer electrolyte membrane to prevent deterioration of the polymer electrolyte membrane.

[0008] However, since the polymer electrolyte membrane must have a certain level of pores distributed to allow ions to pass through, the content of inorganic materials, such as inorganic particles, for improving durability is limited to a certain value or less.

[0009] Accordingly, there is still a need for technology that can prevent deterioration of polymer electrolyte membranes even during long-term operation of fuel cells.

[0010] The present invention aims to improve the durability of a fuel cell system by protecting a polymer electrolyte membrane from peroxide and / or hydroxyl radicals continuously generated in a stack of fuel cell cells.

[0011] According to one aspect, a hollow fiber membrane for a fuel cell humidifier is provided, which comprises a polymer and an antioxidant, wherein the antioxidant is disposed on an inner surface and / or an outer surface of the hollow fiber membrane.

[0012] According to another aspect, there is provided a step of preparing a dope solution for forming a hollow fiber membrane comprising a polymer and an antioxidant;

[0013] A step of discharging the above dope solution into a coagulation tank through a tubular radiator; and

[0014] A step of solidifying the radiation solution discharged into the above-mentioned coagulation tank in the coagulation tank, then winding and drying to obtain a hollow fiber membrane;

[0015] A method for manufacturing a hollow fiber membrane for a fuel cell humidifier is provided, wherein the hollow fiber membrane has an antioxidant disposed on the inner surface and / or the outer surface.

[0016] According to another aspect, a humidifier for a fuel cell including the above hollow fiber membrane is provided.

[0017] According to another aspect, a fuel cell stack comprising a fuel cell cell having a polymer electrolyte membrane; and

[0018] A fuel cell humidifier in communication with the fuel cell stack;

[0019] A fuel cell system is provided in which an antioxidant is leaked from the humidifier and flows into the fuel cell stack at a rate of 1 ug / 1000 hr or more.

[0020] According to one aspect, the hollow fiber membrane has an antioxidant disposed or dispersed on the inner and / or outer surfaces of the hollow fiber membrane, so that when the outside air is humidified in the hollow fiber membrane, the antioxidant flows out from the hollow fiber membrane and flows into the fuel cell stack at a rate of 1 ug / 1000 hr or more, thereby sufficiently preventing deterioration of the polymer electrolyte membrane included in the fuel cell cell in the fuel cell stack, thereby improving durability.

[0021] FIG. 1 and FIG. 2 are exploded perspective views of a fuel cell humidifier according to one embodiment of the present invention.

[0022] Figures 3 to 6 are enlarged views of a cross-section of a hollow fiber membrane according to one embodiment of the present invention.

[0023] FIG. 7 and FIG. 8 are block diagrams illustrating the configuration of a fuel cell system according to one embodiment of the present invention.

[0024] The present inventive concept described below is capable of various modifications and embodiments. Specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present inventive concept to specific embodiments, but should be understood to encompass all modifications, equivalents, or alternatives within the technical scope of the present inventive concept.

[0025] The terminology used below is only used to describe specific embodiments and is not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. Hereinafter, it should be understood that terms such as "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, ingredient, material, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, ingredients, materials, or combinations thereof.

[0026] When a component is referred to as being "connected, coupled" to another component, it should be understood that while the component may be directly connected or coupled to the other component, there may also be a new component between the component and the other component. Conversely, when a component is referred to as being "directly connected" or "directly coupled" to another component, it should be understood that no new component exists between the component and the other component.

[0027] Throughout the specification, when an element, such as a layer, film, region, or plate, is referred to as being "on" or "above" another element, this includes not only instances where the element is directly above the other element, but also instances where there are other elements intervening between them. Terms such as first, second, etc. may be used throughout the specification to describe various components, but the components themselves should not be limited by these terms. These terms are used solely to distinguish one element from another.

[0028] The term "polymer" as used throughout the specification means a polymer formed by polymerization of one or more monomer units, and has a meaning encompassing polymer resins and polymer macromolecules.

[0029] The embodiments described below are merely exemplary, and various modifications are possible from these embodiments.

[0030] According to one aspect, a hollow fiber membrane is provided, comprising a polymer and an antioxidant, wherein the antioxidant is disposed on an inner surface and / or an outer surface.

[0031] The above antioxidant may be arranged on at least one surface of the inner and outer surfaces of the hollow fiber membrane so that some of the antioxidant is released when it comes into contact with the outside air passing through the humidifying membrane.

[0032] According to one embodiment, the hollow fiber membrane has a network structure formed of a polymer, and may further include an antioxidant within the network structure.

[0033] According to one embodiment, the antioxidant may be dispersed within the polymer constituting the hollow fiber membrane. For example, the antioxidant may have a particle shape and may be dispersed and present in a structure embedded within the polymer. That is, the antioxidant may be dispersed within the network structure without forming bonds with the polymer forming the skeleton of the hollow fiber membrane.

[0034] Since the above antioxidant does not form a bond with the hollow fiber membrane, the antioxidant may leak out and be delivered to the fuel cell stack together with the humidified air during the process in which outside air passes through the hollow portion of the hollow fiber membrane.

[0035] According to one embodiment, the antioxidant may be configured to be released from the hollow fiber at a rate of 1 ug / 1000 hr or more. By releasing the antioxidant at a rate exceeding the above amount, chemical deterioration of the polymer electrolyte membrane in the fuel cell stack due to oxidizing substances can be suppressed.

[0036] According to one embodiment, the antioxidant may be incorporated into the hollow fiber membrane by the manufacturing process described below. For example, the antioxidant may be incorporated into the hollow fiber membrane by mixing it into a dope solution during the membrane-forming process, the antioxidant may be incorporated into the hollow fiber membrane by discharging it into the core solution and incorporating it into the hollow fiber membrane during the phase inversion process, or the antioxidant solution may be injected into the hollow portion after the hollow fiber membrane is manufactured to form an antioxidant coating layer on the inner surface of the hollow fiber membrane.

[0037] According to one embodiment, the antioxidant may be dispersed on at least one of the inner and outer surfaces of the hollow fiber or may be in the form of a coating layer. For example, the antioxidant may be attached in the form of particles to at least one of the inner and outer surfaces of the hollow fiber or a plurality of particles may form a coating layer.

[0038] For example, the antioxidant particles can be uniformly distributed over the entire surface so as not to block the pores of the hollow fiber.

[0039] According to one embodiment, the antioxidant may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the polymer.

[0040] According to one embodiment, the antioxidant may form an antioxidant coating layer disposed on at least one surface among the inner and outer surfaces of the hollow fiber. At this time, the antioxidant coating layer may be configured to be able to leak out a certain amount when in contact with the outside air. In order for the antioxidant to be configured to be able to leak out a certain amount, there should be no chemical bonding between the antioxidant and the main polymer of the membrane, and it is advantageous for the antioxidant to be located on the inner surface of the membrane. Therefore, when forming a humidifying membrane, crosslinking agents or additives that may cause crosslinking between the antioxidant and the main polymer should be excluded.

[0041] For example, the antioxidant coating layer may have a thickness of 1 to 50 um so that a certain amount of the antioxidant can flow out. If the thickness of the antioxidant coating layer is less than 1 um, it is difficult to obtain a sufficient amount of antioxidant flow out through contact with the outside air, and if the thickness exceeds 50 um, it may be difficult to achieve sufficient moisture exchange of the outside air because it acts as a resistance layer against the progress of the outside air.

[0042] According to one embodiment, the antioxidant particles or antioxidant coating layer may cover all or part of the inner or outer surface of the hollow fiber.

[0043] According to one embodiment, the antioxidant may be included in an amount of 0.01 to 5 parts by weight relative to 100 parts by weight of the polymer forming the hollow fiber membrane.

[0044] If the above antioxidant is included in an amount of less than 0.01 parts by weight, it is not sufficient to prevent deterioration of the hollow fiber membrane due to peroxide or hydroxyl radicals generated in the fuel cell reaction, and if it exceeds 5 parts by weight, the pores of the hollow fiber membrane may be closed, resulting in a decrease in moisture exchange performance and a deterioration in the membrane humidifier function.

[0045] According to one embodiment, the antioxidant may include a phenolic antioxidant, an amine antioxidant, a metal antioxidant, an organo-metallic antioxidant, a sulfur-based antioxidant, a phosphorus-based antioxidant, or a combination thereof.

[0046] For example, the phenolic antioxidants include Irganox 1010 (Irganox 1010: pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, manufactured by BASF), Irganox 1076 (Irganox 1076: octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, manufactured by BASF), Irganox 1330 (Irganox 1330: 3,3',3",5,5',5"-hexa-t-butyl-a,a',a"-(mesitylene-2,4,6-triyl)tri-p-cresol, manufactured by BASF), and Irganox 3114 (Irganox 3114: 1,3,5-Tris(3,5-di-t-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, manufactured by BASF Corporation), Irganox 3790 (Irganox 3790: 1,3,5-Tris((4-t-butyl-3-hydroxy-2,6-xylyl)methyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, manufactured by BASF Corporation), Irganox 1035 (Irganox 1035: thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], manufactured by BASF Corporation), Irganox 1135 (Irganox 1135: Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-C7-C9 branched alkyl ester, manufactured by BASF Corporation), Irganox 1520L (Irganox 1520L: 4,6-bis(octylthiomethyl)-o-cresol, manufactured by BASF Corporation), Irganox 3125 (Irganox 3125, manufactured by BASF Corporation), Irganox 565 (Irganox 565: 2,4-bis(n-octylthio)-6-(4-hydroxy-3',5'-di-t-butylanilino)-1,3,5-triazine, manufactured by BASF Corporation), Adekastab (registered trademark) AO-80 (Adekastab AO-80: 3,9-bis(2-(3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy)-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, (manufactured by ADEKA Co., Ltd.), Smilizer (registered trademark) BHT, Dong GA-80, Dong GS (above,It may include Cyanox 1790 (manufactured by Sumitomo Chemical Co., Ltd.), Cyanox (registered trademark) 1790 (manufactured by Cytech Co., Ltd.), and Vitamin E (manufactured by Eisai Co., Ltd.), or any combination thereof.

[0047] The amine antioxidant may include phenyl-α-naphthylamine, phenyl-β-naphthylamine, N,N'-diphenyl-p-phenylenediamine, N,N'-di-naphthyl-p-phenylenediamine, HALS compounds, or combinations thereof.

[0048] For example, phosphorus antioxidants include tris(2,4-di-t-butylphenyl)phosphite (Irgafos 168), tris[2-[[2,4,8,10-tetra-t-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl]oxy]ethyl]amine (Irgafos 12), bis(2,4-bis(1,1-dimethylethyl)-6-methylphenyl)ethyl esterphosphite (Irgafos 38), Adecastab 329K, Adecastab PEP36, Adecastab PEP-8, Sandstab P-EPQ, Weston 618, Weston 619G, Ultranox 626, (6-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-t-butyldibenzo[d,f][1,3,2]dioxaphosphepin) (Smilizer GP), or a combination thereof.

[0049] For example, the metal-based antioxidant may include cerium, nickel, tungsten, ruthenium, palladium, silver, rhodium, cesium, zirconium, cobalt, chromium, yttrium, manganese, iron, molybdenum, lead, vanadium, titanium, niobium, lanthanum, ions thereof, oxides thereof, salts thereof, or any mixture thereof.

[0050] For example, the organo-metallic antioxidant may include a Ce-crown complex, a Ce-phosphoric acid complex, a Ce-Bypyridine, or any mixture thereof.

[0051] For example, the sulfur-based antioxidant may include dilaurylthiodipropionate (DLTDP), distearylthiodipropionate (DSTDP), ditridecylthiodipropionate (DMTDP), bis 2-methyl-4(3-alkylthio)-propionyloxy)-5-tert-butylphenol sulfide, tetrakis methylene-3-(laurylthio)propionate methane, or combinations thereof.

[0052] According to one embodiment, the hollow fiber membrane may include a polymer, and the polymer may be selected from known polymers suitable for forming a hollow fiber membrane, and may include, for example, a polyvinylidene fluoride (PVDF) polymer, a polysulfone polymer, a sulfonated polysulfone, cellulose acetate, cellulose triacetate, polymethyl methacrylate, Nafion, a polystyrene (PS) polymer, a polytetrafluoroethylene (PTFE) polymer, a perfluorosulfonic acid (PFSA) polymer, a polyphenylsulfone polymer, a polyethersulfone (PES) polymer, a polyacrylonitrile (PAN) polymer, a polyetherimide (PEI) polymer, a polyimide (PI) polymer, or any combination of the above-mentioned polymers.

[0053] For example, the polymer may include a polystyrene-based polymer.

[0054] The hollow fiber membrane comprises one or more of the polymers listed above as a main polymer, and may further comprise an auxiliary polymer, taking into account the desired properties of the hollow fiber membrane. For example, the auxiliary polymer may be polyvinylpyrrolidone.

[0055] According to one embodiment, the polymer may be included in an amount of 90 parts by weight or more and less than 100 parts by weight, or 95 parts by weight to 99.999 parts by weight, based on 100 parts by weight of the hollow fiber membrane.

[0056] According to one embodiment, the auxiliary polymer may be included in an amount of 5 to 20 parts by weight per 100 parts by weight of the hollow fiber membrane.

[0057] According to one embodiment, the thickness of the hollow fiber membrane may be 0.5 nm to 1 mm.

[0058] According to one embodiment, the hollow fiber membrane may further include additives such as a surfactant, a hydrophilic organic compound, a hydrophilic polymer, or a crosslinking agent.

[0059] For example, the additive may include at least one of polyethylene glycol, glycerin, diethyl glycol, triethylene glycol, ethanol, polyvinylpyrrolidone, water, zinc chloride, and lithium chloride.

[0060] These additives can be selected and added in appropriate amounts, as long as they do not impair the inherent properties of the hollow fiber membrane. It will be apparent to those skilled in the art that any known materials used in the manufacture of hollow fiber membranes can also be used.

[0061]

[0062] According to one aspect, a method for manufacturing a hollow fiber membrane for a fuel cell humidifier is provided, comprising the step of providing a hollow fiber membrane configured to allow an antioxidant to leak out.

[0063] Humidifiers for fuel cells supply humidified air to fuel cell stacks. Impurities in the humidified air can potentially reduce the lifespan of the fuel cell. Therefore, it is necessary to suppress the release of impurities resulting from the decomposition of hollow fiber materials. Because hollow fibers are essentially formed from organic polymers, exposure to the high temperature and humidity generated from the stack during fuel cell operation can cause polymer deformation, short-circuiting, or the formation of various impurity ions due to polymer decomposition. These impurities can be transferred into the stack, potentially degrading its performance.

[0064] To address these issues, attempts have been made to enhance the durability of hollow fiber membranes by adding fluorinated polymers or by providing a durable coating layer on the surface of the membrane. However, the addition of fluorinated materials and the provision of a durable coating layer still have limitations, such as hindering the moisture exchange capacity of the hollow fiber membrane or reducing its heat resistance.

[0065] Accordingly, the inventor of the present invention conducted research focusing on substances that cause the decomposition of hollow fiber membranes, and studied a direction for fundamentally removing oxidizing substances that flow into the membrane humidifier from the fuel cell stack together with high-temperature and humid air. In relation to this, since injecting a large amount of antioxidant into the fuel cell stack to remove oxidizing substances generated in the fuel cell stack may act as an impurity in the fuel cell stack and reduce efficiency, the inventors completed the present invention based on the finding that if the hollow fiber membrane included in the fuel cell humidifier is configured to allow a constant amount of antioxidant to flow out for a long time, the antioxidant can be continuously supplied to the fuel cell stack, contributing to the removal of oxidizing substances.

[0066] According to one embodiment, the step of providing a hollow fiber membrane configured to allow the antioxidant to flow out may include the step of preparing a dope solution for forming a hollow fiber membrane.

[0067] According to one embodiment, the dope solution may include a step of mixing a polymer and an antioxidant in an organic solvent, wherein the antioxidant is mixed in an amount of 0.01 to 5 parts by weight relative to 100 parts by weight of the polymer, to obtain a spinning solution. In this case, the organic solvent used in the preparation of the dope solution may be a third solvent described below, for example, N-methyl-2-methylpyrrolidone.

[0068] The solvent may include at least one of a first solvent, a second solvent, and a third solvent. For example, the solvent may be a mixed solvent including two types of solvents among the first solvent, the second solvent, and the third solvent.

[0069] The first solvent is a solvent that cannot dissolve the polymer at room temperature (e.g., 23 to 25°C) but can dissolve the polymer at high temperatures (e.g., 80°C or higher), and may include butanol, isobutanol, octanol, pentanol, isopentanol, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, polyoxylethylene octylphenyl ether, or a combination thereof.

[0070] The second solvent is a solvent that cannot dissolve the polymer, and may include water, methanol, ethanol, isopropanol, acetone, hexane, pentane, benzene, toluene, carbon tetrachloride, o-dichlorobenzene, polyethylene glycol, or a combination thereof.

[0071] The third solvent is a solvent that can dissolve the polymer even at room temperature, and may include N-methyl-2-pyrrolidone, dimethyl sulfoxide, dimethyl acetamide, dimethyl formamide, methyl ethyl ketone, tetrahydrofuran, tetramethyl urea, or trimethyl phosphate.

[0072] A person skilled in the art can use one or a mixture of two or more of the first solvent, the second solvent, and the third solvent, taking into consideration the characteristics of the polymer raw material and the production of a hollow fiber membrane having desired properties.

[0073] According to one embodiment, when the solvent is a mixed solvent of two types of solvents, the mixing ratio of the solvents may be 1:9 to 9:1 by weight, but is not limited thereto, and a person skilled in the art may select an appropriate range by considering the content of the polymer and the antioxidant, the viscosity of the spinning solution, the porosity of the hollow fiber membrane, and the physical properties of the final hollow fiber membrane.

[0074] According to one embodiment, the spinning solution comprises a polymer forming the skeleton of a hollow fiber membrane, an antioxidant, a solvent, and, if necessary, additional additives. The solvent is removed during the spinning solution forming into a hollow fiber membrane, so that the final product has a structure in which the antioxidant is incorporated into the polymer skeleton.

[0075] According to one embodiment, the content of the polymer contained in the spinning solution may be 15 to 25 parts by weight based on 100 parts by weight of the total spinning solution. For example, the content of the polymer contained in the spinning solution may be 16 to 24 parts by weight, 17 to 23 parts by weight, 18 to 22 parts by weight, or 19 to 21 parts by weight.

[0076] According to one embodiment, the content of the antioxidant included in the above-mentioned radiation source may be more than 0 and less than 5 parts by weight, or 0.001 to 5 parts by weight, relative to 100 parts by weight of the polymer forming the skeleton of the hollow fiber membrane.

[0077] According to one embodiment, the temperature at which the polymer, antioxidant, and optionally additives are mixed in the solvent in the step of obtaining the above-described radiation source may be appropriately selected at room temperature or high temperature in consideration of the polymer, antioxidant, additive, and solvent used.

[0078] According to one embodiment, the mixing time of the above-described radiation source may be performed for a time sufficient for the polymer, antioxidant, and any additives to be sufficiently dissolved and / or dispersed in the solvent.

[0079] According to one embodiment, the viscosity of the spinning solution may be 5,000 to 50,000 cps at 35°C. When the viscosity of the spinning solution satisfies the above range, the spinning solution can be smoothly discharged through the nozzle without clogging.

[0080] In order to maintain the viscosity of the above-mentioned spinning solution within the aforementioned range, the temperature of the spinning nozzle may be adjusted to a temperature above a certain temperature. Alternatively, the spinning solution may further include a viscosity modifier to control the viscosity as needed.

[0081] According to one embodiment, the spinning solution may further include an additive in consideration of the membrane forming properties and porosity of the hollow fiber membrane, the dispersibility of the antioxidant, and the viscosity of the spinning solution.

[0082] For example, the additive may include at least one of polyethylene glycol, glycerin, diethyl glycol, triethylene glycol, ethanol, polyvinylpyrrolidone, water, zinc chloride, and lithium chloride.

[0083] According to one embodiment, the step of irradiating the above-mentioned radiation source into the coagulation tank may include a step of irradiating the discharge liquid using a tubular radiation device, for example, a double-tubular radiation device or a triple-tubular radiation device, but is not limited to such a tubular type, and any discharge method capable of forming a hollow shape may be used without limitation.

[0084] According to one embodiment, when the spin-off solution is discharged into the coagulation tank through a double-tube type spin-off device, the composition of the spin-off solution discharged from each tube of the double-tube type may be the same or different. For example, when the spin-off solution is discharged using a triple-tube type spin-off device, the composition of the spin-off solution passing through each tube may be the same or different. For example, when a triple-tube type spin-off device is used, the composition of the spin-off solution passing through the tubes arranged on the inner and outer sides of the tube may be the same, and only the composition of the spin-off solution passing through the intermediate tube between the inner and outer sides may be different.

[0085] According to one embodiment, in the step of irradiating the above-mentioned radiation source into the coagulation tank, the radiation temperature may be set to a temperature equal to or higher than the radiation source mixing temperature. In this case, when using a multi-tubular nozzle, the temperature of each nozzle may be set differently, enabling the optimal radiation source to be discharged at an appropriate temperature.

[0086] According to one embodiment, in the step of radiating the above-mentioned radiation source into the coagulation tank, the discharge speed may be 5 to 100 g / min.

[0087] According to one embodiment, when the above-mentioned radiation source is discharged through a tubular nozzle, a core liquid (core liquid) may be discharged together into the inner hollow portion of the tubular body. The core liquid may include a mixed solution of a second solvent and a third solvent.

[0088] According to one embodiment, the core solution may be a mixture of a second solvent and a third solvent in a volume ratio of 3:7 to 7:3. When the core solution satisfies the volume ratio within the above range, an antioxidant contained in the core solution may be incorporated into the hollow fiber membrane during the phase conversion process of the radiation.

[0089] According to one embodiment, the core solution may further include an antioxidant. By further including an antioxidant in the core solution, the antioxidant can be dispersed onto the inner surface of the hollow fiber membrane through phase separation during the hollow fiber membrane formation process. As a result, the antioxidant can be dispersed and present at a high concentration on the inner surface of the hollow fiber membrane. As described above, when the core solution containing the antioxidant is discharged together, the antioxidant can be contained in small amounts or not at all in the spinning solution.

[0090] According to one embodiment, the radiation emitted from the radiation device can contact the coagulation liquid in the coagulation tank through the air gap.

[0091] The above air gap is the region where the radiant comes into contact with air, and artificial cooling air can be introduced therein, taking into account the physical properties of the radiant. For example, the length of the air gap can be set to 0.1 to 50 cm. The air gap is the region where the first phase transition occurs, where the phase transition is achieved by exchanging moisture in the atmosphere with the organic solvent in the radiant solution. When the length of the air gap satisfies the above range, sufficient phase transition occurs, and a hollow fiber membrane having a desired pore structure can be obtained.

[0092] The above radiation passes through the air gap and comes into contact with the coagulation liquid contained in the coagulation tank, thereby solidifying and forming a porous hollow fiber membrane.

[0093] According to one embodiment, the coagulation tank may be configured as a single tank, but is not limited thereto, and may be configured such that two or more coagulation tanks are arranged in series. When there are two or more coagulation tanks, the coagulant used in each coagulation tank may be the same or different.

[0094] According to one embodiment, the coagulant contained in the coagulation tank serves to coagulate the discharged liquid through the detention into the form of a hollow fiber membrane, and the coagulant used at this time can be appropriately selected and used by a person skilled in the art from among known coagulants by considering the porosity of the hollow fiber membrane, the pore structure of the hollow fiber membrane, etc.

[0095] For example, a second solvent such as an acidic solution or water may be used as the coagulant.

[0096] According to one embodiment, the hollow fiber membrane obtained through the above coagulation tank may undergo a post-processing step.

[0097] According to one embodiment, the post-treatment step may include performing a chemical treatment and / or a physical treatment.

[0098] For example, the chemical treatment in the above post-treatment step is performed to remove and dry the coagulant contained in the pores after the hollow fiber membrane is formed, and may include water washing, washing, hot water treatment, etc., and if necessary, the solution used for water washing, washing, hot water treatment, etc. may further include an antioxidant.

[0099] For example, the physical treatment in the above post-processing step may further include a stretching or shrinking process to control the size and shape of the pores inside the hollow fiber membrane to improve the strength and durability of the hollow fiber membrane.

[0100] According to one embodiment, after forming a hollow fiber membrane, a post-treatment may be performed by injecting a solution of an antioxidant dissolved in a second solvent into the hollow portion of the hollow fiber, followed by drying. Through this post-treatment, an antioxidant coating layer may be provided on the inner surface of the hollow fiber membrane. The post-treatment for providing an antioxidant coating layer on the inner surface of the hollow fiber membrane may be performed additionally to the process described above, or may be performed for the purpose of forming a selective antioxidant coating layer only on the inner surface of a hollow fiber membrane, either with or without an antioxidant, after forming the hollow fiber membrane.

[0101] The hollow fiber membrane for a fuel cell humidifier manufactured through the aforementioned process does not have an antioxidant bound to the hollow fiber through a crosslinking agent or binder, but is dispersed inside the hollow fiber membrane or forms a coating layer on the inner surface of the hollow fiber membrane, so that the antioxidant is easily dissolved into the external air during the moisture exchange process of the hollow fiber membrane.

[0102]

[0103]

[0104] According to another aspect, a humidifier including the above hollow fiber membrane is provided.

[0105] For the hollow fiber desert, please refer to the above, and below, the humidifier will be described with reference to FIGS. 1 and 2.

[0106] Figures 1 and 2 are perspective views of a fuel cell humidifier (100) according to one embodiment of the present invention.

[0107] As shown in FIGS. 1 and 2, the fuel cell humidifier (100) of the present invention includes a middle case (110), a cap case (120), a fixing part (130), and a hollow fiber membrane bundle (200).

[0108] Here, the hollow fiber membrane bundle (200) may have antioxidant particles distributed on each surface of the hollow fiber membrane, or may include an antioxidant coating layer on the surface. For enlarged views of the hollow fiber membrane surface, refer to FIGS. 3 and 4.

[0109] The middle case (110) is combined with the cap case (120) to form the outer shape of the membrane humidifier (100). The middle case (110) and the cap case (120) may be made of a hard plastic such as polycarbonate or a metal. The middle case (110) and the cap case (120) may have a circular cross-sectional shape in the width direction, as shown in FIG. 1, or a polygonal cross-sectional shape in the width direction, as shown in FIG. 2. The polygon may be a rectangle, a square, a trapezoid, a parallelogram, a pentagon, a hexagon, etc., and the polygon may have rounded corners. In addition, the circle may be an oval.

[0110] In the middle case (110), a second fluid inlet (112) through which the second fluid is supplied and a second fluid outlet (113) through which the second fluid is discharged are formed.

[0111] In FIGS. 1 and 2, a plurality of hollow fiber membranes (210) are arranged in the middle case (110) in the form of a single hollow fiber membrane bundle (200), but the hollow fiber membranes (210) may also be arranged in the middle case (110) in a state of being divided and accommodated in two or more cartridges.

[0112] A fluid inlet (121) is formed in the cap case (120). The fluid inlet (121) formed in one of the cap cases (120) respectively connected to both ends of the middle case (110) becomes a first fluid inlet, and the fluid inlet (121) formed in the other one becomes a first fluid outlet. The first fluid introduced through the fluid inlet (121) functioning as the first fluid inlet passes through the internal conduits (i.e., lumens) of the hollow fiber membranes (210) accommodated inside the middle case (110) and then exits through the fluid inlet (121) functioning as the first fluid outlet.

[0113] The ends of the hollow fiber membranes (210) are potted in the fixing member (130). The fixing member (130) binds the hollow fiber membranes (210) and fills the gap between the hollow fiber membranes (210) and the gap between the hollow fiber membranes (210) and the middle case (110). As a result, each of the two ends of the middle case (110) is blocked by the fixing member (130), and a flow path through which a second fluid passes is formed therein. The material of the fixing member (130) is known in the art, and a detailed description thereof is omitted herein.

[0114] FIGS. 3 to 6 are enlarged views showing the cross-section of one of the hollow fiber membrane bundles according to one embodiment of the present invention. The enlarged views of FIGS. 3 to 5 illustrate an embodiment in which antioxidant particles or an antioxidant coating layer are disposed only on the outer surface of the hollow fiber according to one embodiment of the present invention, but the present invention is not necessarily limited thereto, and an embodiment in which antioxidant particles or an antioxidant coating layer are provided on the inner surface of the hollow fiber, or on both the inner and outer surfaces, also corresponds to one embodiment of the present invention.

[0115] Referring to FIGS. 3 to 6, the hollow fibers (30, 40, 50, 60) include cavities (300, 400, 500, 600), which are passages for air movement and locations where moisture exchange occurs. The hollow fiber membrane includes an inner surface (S2), which is a surface on the cavity side, and an outer surface (S1) facing the outside of the hollow fiber membrane. The hollow fiber has a thickness region (310, 410, 510, 610) between the inner surface (S2) and the outer surface (S1), and the thickness region (310, 410, 510, 610) has a porous structure, although not shown. The porosity of the thickness region can be configured to allow moisture exchange between moist air provided from the fuel cell stack and dry air from the outside. An antioxidant particle (320, 520) or an antioxidant coating layer (420, 620) including antioxidant particles is provided on the outer surface (S1) or inner surface (S2) of the hollow fiber (30, 40, 50, 60). At this time, the antioxidant particles (320, 520) and the antioxidant coating layer (420, 620) may be provided in an amount that does not close the pores arranged in the thickness region (310, 410, 510, 610). In addition, the antioxidant particles (320, 520) and the antioxidant coating layer (420, 620) may be arranged so as not to close the gaps between adjacent hollow fiber membranes when the hollow fibers (30, 40, 50, 60) are bundled. That is, the thickness of the antioxidant coating layer (420, 620) is configured to not exceed half the width of the hollow fiber membrane gap in the hollow fiber membrane bundle, and the antioxidant particles (320, 520) are provided to be uniformly dispersed on the surface.

[0116] Although not shown, in addition to FIGS. 3 to 6, a structure in which antioxidant particles and an antioxidant coating layer are mixed on the inner or outer surface can be understood by those skilled in the art, and therefore, further description thereof is omitted herein.

[0117]

[0118] According to another aspect, a fuel cell system is provided, comprising: a fuel cell stack including a fuel cell cell having a polymer electrolyte membrane; and a humidifier communicating with the fuel cell stack; wherein an antioxidant flows out from the humidifier and flows into the fuel cell stack at a rate of 1 ug / 1000 hr or more.

[0119] Referring to FIG. 7, a fuel cell system according to one embodiment of the present invention includes a fuel cell stack (1000), a hydrogen supply unit (2000), and an air supply unit (3000).

[0120] The above fuel cell stack (1000) generates heat and steam by reacting hydrogen supplied from a hydrogen supply unit (2000) and oxygen supplied from an air supply unit (3000).

[0121] The above fuel cell stack (1000) is composed of a membrane-electrode assembly, an electrolyte membrane, a catalyst layer, electrodes of a cathode and an anode, a gas diffusion layer, a separator, and a gasket, and each component can be manufactured using known materials by a known method.

[0122] The fuel cell stack (1000) above generates electricity through a combination reaction of hydrogen and oxygen. Specifically, the fuel cell stack (1000) is supplied with hydrogen on the anode side and with oxygen on the cathode side. On the anode side, hydrogen ions are generated through an oxidation reaction of hydrogen, and the electrons generated at this time move to the cathode side through a wire. The hydrogen ions move to the cathode side through the electrolyte membrane, come into contact with oxygen, and form water vapor.

[0123] Since the reduction reaction of oxygen at the cathode electrode of a polymer electrolyte fuel cell proceeds with the formation of hydrogen peroxide as an intermediate reaction, hydrogen peroxide or hydroxyl radicals may be generated at the cathode electrode. In addition, at the anode electrode of the polymer electrolyte fuel cell, hydrogen peroxide or hydroxyl radicals may also be generated at the anode electrode as oxygen molecules permeate the polymer electrolyte membrane. The hydrogen peroxide or hydroxyl radicals thus generated may cause deterioration of the polymer electrolyte membrane, which is poor at oxidizing substances.

[0124] In an effort to prevent the deterioration of such polymer electrolyte membranes, a method of introducing radical scavengers onto the surface of the polymer electrolyte membrane has been proposed. However, when an excessive amount of radical scavengers is used to improve durability, there has been a problem of a decrease in ion exchange rate due to pore closure of the ion exchange membrane. Furthermore, the loss of radical scavengers present on the surface of the polymer electrolyte membrane occurred during fuel cell operation, and due to this, the durability of the polymer electrolyte membrane has decreased, making it difficult to obtain sufficient durability life characteristics.

[0125] The inventor of the present invention has conducted in-depth research to solve the deterioration of fuel cell durability due to hydrogen peroxide or hydroxyl radicals generated in the fuel cell stack, and has completed the present invention based on the finding that the durability life characteristics of the fuel cell are obtained when air containing an antioxidant is continuously supplied from a humidifier (3200) included in an air supply unit (300) provided upstream of the fuel cell stack.

[0126] Specifically, the hollow fiber membrane included in the humidifier (3200) releases antioxidants at a rate of 1 ug / 1000 hr or more and is included in the air flowing into the fuel cell stack.

[0127] The above hydrogen supply unit (2000) supplies stored hydrogen to the fuel cell stack (1000). Any hydrogen supply unit capable of supplying hydrogen to the fuel cell stack can be used without limitation.

[0128] The above air supply unit (3000) includes an air compression unit (3100) that compresses outside air to generate a first fluid and a humidifier (3200) that humidifies the first fluid and transmits it to a fuel cell stack.

[0129] The air compression unit (3100) receives outside air and supplies the compressed first fluid into the humidifier. The air compression unit (3100) is a device that compresses a fluid such as air, and may include, for example, a blower, a compressor, etc.

[0130] If necessary, an additional filter may be installed in front of the inlet of the air compression unit to block the ingress of contaminants, or a separate air filter may be provided.

[0131] The humidifier (3200) receives compressed air from the air compression unit (3100), humidifies the air, and supplies it to the fuel cell stack.

[0132] The humidifier (3200) exchanges moisture between air from the outside and steam generated from the fuel cell stack (1000), and supplies the humidified air into the fuel cell stack (1000).

[0133]

[0134] According to another aspect, a fuel cell system comprises a fuel cell stack (1000); a hydrogen supply unit (2000) for supplying hydrogen to the stack; an air supply unit (3000) for supplying air to the stack, wherein the air supply unit includes an air compression unit (3100) and a humidifier (3200); and a filter unit disposed on a path along which outside air passing through the humidifier (3200) moves to the fuel cell stack and configured to remove peroxide and / or hydroxyl radicals.

[0135] This fuel cell system is described with reference to FIG. 8.

[0136] Among the systems of FIG. 8, the fuel cell stack (1000) and the hydrogen supply unit (2000) are as described in FIG. 7, and the air supply unit (3000) is as described in FIG. 5 for the humidifier (3200), except that the hollow fiber membrane included in the humidifier (3200) does not include an antioxidant.

[0137] The above filter unit (4000) may be arranged between the humidifier (3200) and the fuel cell stack (1000). Specifically, the filter unit (4000) may be arranged adjacent to an outlet of outside air (i.e., first fluid) passing through the humidifier, adjacent to an inlet through which the first fluid flows into the fuel cell stack, or arranged in a path along which the first fluid moves between the humidifier and the fuel cell stack.

[0138] The above filter unit (4000) may include a porous substrate; and an antioxidant provided on the surface of the porous substrate.

[0139] The porous substrate may be a porous nonwoven fabric. For example, the porous substrate includes a membrane having an average pore size of 50 nm to 10 μm on its surface. The porous substrate may optionally include either a hydrophilic membrane or a hydrophobic membrane. For example, and without limitation, the porous substrate may include a membrane comprising a thermoplastic polymer, including polyethylene, polypropylene, 1-octene, styrene, a polyolefin (co)polymer, polyamide, poly-1-butene, poly-4-methyl-1-pentene, polyether sulfone, ethylene tetrafluoroethylene, polyvinylidene fluoride, polysulfone, polyacrylonitrile, polyamide, cellulose acetate, cellulose nitrate, regenerated cellulose, polyvinyl chloride, polycarbonate, polyethylene terephthalate, polyimide, polytetrafluoroethylene, ethylene chlorotrifluoroethylene, or a combination thereof.

[0140] The above porous substrate may include any known substrate having a mesh shape.

[0141] The above antioxidant may be provided on one or both sides of the porous substrate. For example, the antioxidant may be provided on both sides of the porous substrate, and the concentration of the antioxidant provided on the first side facing the fuel cell stack (1000) may be higher than the concentration of the antioxidant provided on the second side opposite the first side.

[0142] For information on the above antioxidants, refer to the above.

[0143]

[0144] Hereinafter, an embodiment of the present invention will be described through examples and comparative examples, and the scope of the present invention is not intended to be limited to the examples.

[0145]

[0146] (Example)

[0147] Example 1

[0148] The dope stock solution was prepared by mixing 20 wt% polystyrene (PS), 6% polyvinyl pyrrolidone (PVP), and 1% antioxidant Irganox1010 with 73% solvent N-methyl pyrrolidone (NMP). The core solution was prepared by mixing N-methyl pyrrolidone and ethanol in a volume ratio of 6:4. The dope stock solution was discharged through the outer tube of the double-tube nozzle and the core solution was discharged through the inner tube, thereby immersing the radiant material in a coagulation tank containing a coagulation solution. The radiant material came into contact with the coagulation solution in the coagulation tank and was formed into a hollow fiber membrane. At this time, the coagulation solution used was water and polyethylene glycol (PEG) in a 1:1 ratio, and the temperature was adjusted to 40℃. The hollow fiber membrane that passed through the coagulation tank was washed with water at 40℃ in a washing tank and then dried to obtain a hollow fiber membrane. At this time, the thickness of the hollow fiber membrane was 150 um.

[0149]

[0150] Comparative Example 1

[0151] The dope stock solution was prepared by mixing 20 wt% polystyrene (PS), 6% polyvinyl pyrrolidone (PVP), and 1% antioxidant Irganox1010 with 73% solvent N-methyl pyrrolidone (NMP). The core solution was prepared by mixing N-methyl pyrrolidone and ethanol in a volume ratio of 75:25. The dope stock solution was discharged through the outer tube of the double-tube nozzle and the core solution was discharged through the inner tube, thereby immersing the radiant material in a coagulation tank containing a coagulation solution. The radiant material came into contact with the coagulation solution in the coagulation tank and was formed into a hollow fiber membrane. At this time, the coagulation solution used was water and polyethylene glycol (PEG) in a 1:1 ratio, and the temperature was adjusted to 40℃. The hollow fiber membrane that passed through the coagulation tank was washed with water at 40℃ in a washing tank and then dried to obtain a hollow fiber membrane. At this time, the thickness of the hollow fiber membrane was 150 um.

[0152]

[0153] Comparative Example 2

[0154] The dope stock solution was prepared by mixing 20 wt% polystyrene (PS), 6% polyvinyl pyrrolidone (PVP), and 74% N-methyl pyrrolidone (NMP) as the solvent, and the core solution was prepared by mixing N-methyl pyrrolidone and ethanol in a volume ratio of 6:4. The dope stock solution was discharged through the outer tube of the double-tube nozzle, and the core solution was discharged through the inner tube, thereby immersing the radiant material in a coagulation tank containing a coagulation solution. The radiant material came into contact with the coagulation solution in the coagulation tank and was formed into a hollow fiber membrane. At this time, the coagulation solution used was water and polyethylene glycol (PEG) in a 1:1 ratio, and the temperature was adjusted to 40°C. The hollow fiber membrane that passed through the coagulation tank was washed with water at 40°C in a washing tank and then dried to obtain a hollow fiber membrane. At this time, the thickness of the hollow fiber membrane was 150 μm.

[0155]

[0156] Evaluation Example 1

[0157] When a humidifier module including the hollow fiber membrane manufactured in Example 1 and Comparative Example 1 was manufactured and mounted on a fuel cell system and operated, the content of antioxidant remaining in the hollow fiber membrane after 1000 hours was measured by the following method, and is shown in Table 1 below.

[0158] [Method for measuring antioxidant content]

[0159] The antioxidant content was measured using 1H-NMR. The prepared hollow fiber membrane was dissolved in DMSO-D6 and measured, and the total content was calculated by comparing the integral ratio of the proton peak of the main polymer and the proton peak of the antioxidant.

[0160] Fuel cell operation pre-humidification membrane 1g per 1000hr operation post-humidification membrane 1g per 1000hr operation Example 196000 μg 95000 μg Comparative example 10 μg 0 μg

[0161]

[0162] As shown in Table 1 above, the membrane humidifier including the hollow fiber membrane of Example 1 showed a decrease in the content of the antioxidant after 1000 hours of fuel cell operation, which suggests that the antioxidant was transferred from the membrane humidifier into the fuel cell stack. Comparative Example 1 confirmed that the antioxidant was not included in the final manufactured membrane humidifier even though the antioxidant was included in the dope solution, which suggests that the mixing ratio of the core solution is important in order to keep the antioxidant inside during the hollow fiber membrane forming process.

[0163]

[0164] Evaluation Example 2

[0165] When a humidifier module including the hollow fiber membrane manufactured in Example 1 and Comparative Example 2 was manufactured and installed in a fuel cell system and operated, the gas permeability of the polymer electrolyte membrane in the stack after 1000 hours was measured using the following method, and the results are shown in Table 2.

[0166] [Method for Measuring Gas Permeability of Polymer Electrolyte Membranes]

[0167] The gas permeability of a polymer electrolyte membrane is measured by cutting the polymer electrolyte membrane into a circle with a diameter of 50 mm, mounting it on a measuring jig, and applying hydrogen gas at a pressure of 0.5 bar to measure the amount of hydrogen that permeates.

[0168] After 1000 hours of operation, the gas permeability of the polymer electrolyte membrane was compared with Example 2. The reduction rate was 20.030 cc / min.m. 2 Control Example 10.020 cc / min.m 2 About 30%

[0169] As shown in Table 2 above, the polymer electrolyte membrane in the fuel cell stack supplied with an antioxidant from a membrane humidifier was suppressed from chemical deterioration by oxidizing substances, and thus, it was confirmed that the gas permeability was reduced by approximately 30% compared to Comparative Example 2 in which the antioxidant was not supplemented.

[0170] It was confirmed that when the hollow fiber membrane manufactured according to Example 1 is applied to a membrane humidifier and used in a fuel cell system, the membrane humidifier serves to supply an antioxidant into the fuel cell stack, thereby preventing chemical deterioration of the polymer electrolyte membrane in the fuel cell stack.

Claims

1. Contains polymers and antioxidants, A hollow fiber membrane for a fuel cell humidifier, wherein the above antioxidant is disposed on the inner surface and / or the outer surface.

2. In paragraph 1, A hollow fiber membrane for a fuel cell humidifier, wherein the polymer forms a network structure and the antioxidant is dispersed and present within the network structure.

3. In paragraph 1, A hollow fiber membrane for a fuel cell humidifier, wherein the above antioxidant is configured to be released from the hollow fiber membrane in an amount of 1 μg or more for 1000 hours when the fuel cell is operated.

4. In paragraph 1, A hollow fiber membrane for a fuel cell humidifier, wherein the polymer comprises a polyvinylidene fluoride (PVDF) polymer, a polysulfone polymer, a sulfonated polysulfone, cellulose acetate, cellulose triacetate, polymethyl methacrylate, Nafion, a polystyrene (PS) polymer, a polytetrafluoroethylene (PTFE) polymer, a perfluorosulfonic acid (PFSA) polymer, a polyphenylsulfone polymer, a polyethersulfone (PES) polymer, a polyacrylonitrile (PAN) polymer, a polyetherimide (PEI) polymer, a polyimide (PI) polymer, or any combination thereof.

5. In paragraph 4, A hollow fiber membrane for a fuel cell humidifier, wherein the polymer comprises a polysulfone-based polymer, a sulfonated polysulfone, a polystyrene (PS)-based polymer, a polyethersulfone (PES)-based polymer, or any combination thereof.

6. In paragraph 1, A hollow fiber membrane for a fuel cell humidifier, wherein the polymer is contained in an amount of 90 parts by weight or more and less than 100 parts by weight per 100 parts by weight of the hollow fiber membrane.

7. In paragraph 1, A hollow fiber membrane for a fuel cell humidifier, wherein the antioxidant comprises a phenol-based antioxidant, an amine-based antioxidant, a metal-based antioxidant, an organo-metallic antioxidant, a sulfur-based antioxidant, a phosphorus-based antioxidant, or a combination thereof.

8. In paragraph 1, A hollow fiber membrane for a fuel cell humidifier, wherein the antioxidant is contained in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the polymer.

9. In paragraph 1, The hollow fiber membrane for a fuel cell humidifier further comprises polyvinylpyrrolidone.

10. A step of preparing a dope solution for forming a hollow fiber membrane containing a polymer and an antioxidant; A step of discharging the above dope solution into a coagulation tank through a tubular radiator; and A step of solidifying the radiation solution discharged into the above-mentioned coagulation tank in the coagulation tank, then winding and drying to obtain a hollow fiber membrane; The above hollow fiber membrane is a method for manufacturing a hollow fiber membrane for a fuel cell humidifier, wherein an antioxidant is disposed on the inner surface and / or the outer surface.

11. In paragraph 10, A method for manufacturing a hollow fiber membrane for a fuel cell humidifier, comprising the step of obtaining a spinning dope solution by mixing a polymer and an antioxidant in an organic solvent, wherein the antioxidant is mixed in an amount of 0.01 to 5 parts by weight relative to 100 parts by weight of the polymer.

12. In paragraph 10, The above tubular radiator contains a mixed solution of a second solvent and a third solvent in a volume ratio of 3:7 to 7:3 as a core liquid in the hollow part, The second solvent comprises water, methanol, ethanol, isopropanol, acetone, hexane, pentane, benzene, toluene, carbon tetrachloride, o-dichlorobenzene, polyethylene glycol, or a combination thereof. A method for producing a hollow fiber membrane for a fuel cell humidifier, wherein the third solvent comprises N-methyl-2-pyrrolidone, dimethyl sulfoxide, dimethyl acetamide, dimethyl formamide, methyl ethyl ketone, tetrahydrofuran, tetramethyl urea, trimethyl phosphate, or a combination thereof.

13. In paragraph 12, A method for manufacturing a hollow fiber membrane for a fuel cell humidifier, wherein the above-mentioned core solution further contains an antioxidant.

14. A fuel cell humidifier comprising a hollow fiber membrane according to any one of claims 1 to 9.

15. A fuel cell stack comprising a fuel cell having a polymer electrolyte membrane; and A humidifier according to claim 14, which is in communication with the fuel cell stack; A fuel cell system in which an antioxidant leaks from the humidifier and flows into the fuel cell stack at a rate of 1 ug / 1000 hr or more.

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