Fuel cell humidifier and manufacturing method thereof

Abstract

Disclosed are a fuel cell humidifier capable of reliably preventing gas leakage due to repeated operation and stop of a fuel cell and capable of being manufactured at a lower manufacturing cost and a higher productivity, and a method of manufacturing the same. The fuel cell humidifier of the present invention comprises a humidification module and caps respectively coupled to both ends of the humidification module, wherein: the humidification module comprises an intermediate housing, a plurality of hollow fiber membranes in the intermediate housing, a fixing layer in which the ends of the hollow fiber membranes are encapsulated, and a composite gasket having a groove into which the ends of the intermediate housing are inserted; the composite gasket comprises an inner body, an outer body and a connecting body arranged between the inner body and the outer body and made of a first material. At least a portion of the inner body adheres to the securing layer and is formed of a second material different from the first material.

Description

[0001] This case is a divisional application, and its parent case is an application with an application date of June 24, 2020, application number 202080047053.2, and invention name “Fuel cell humidifier and its manufacturing method”. Technical Field

[0002] The present disclosure relates to a humidifier for a fuel cell and a method for manufacturing the same, and more particularly, to a humidifier for a fuel cell and a method for manufacturing the same, which can reliably prevent gas leakage caused by repeated operation and stop of the fuel cell and can be manufactured at a lower manufacturing cost and higher productivity. Background Art

[0003] A fuel cell is a power generation cell that combines hydrogen and oxygen to generate electricity. Fuel cells have the following advantages: unlike ordinary chemical batteries such as dry cells or storage batteries, they can generate electricity continuously as long as hydrogen and oxygen are supplied, and there is no heat loss, so the efficiency of fuel cells is about twice that of internal combustion engines.

[0004] In addition, the fuel cell directly converts chemical energy generated by the combination of hydrogen and oxygen into electrical energy, thereby emitting a small amount of pollutants. Therefore, the fuel cell has the following advantages: the fuel cell is environmentally friendly and can reduce concerns about resource depletion due to increased energy consumption.

[0005] Based on the type of electrolyte used, such fuel cells can generally be classified as polymer electrolyte membrane fuel cells (PEMFC), phosphoric acid fuel cells (PAFC), molten carbonate fuel cells (MCFC), solid oxide fuel cells (SOFC) or alkaline fuel cells (AFC) etc.

[0006] These fuel cells basically work according to the same principle, but differ from each other in the type of fuel used, operating temperature, catalyst and electrolyte. Among these fuel cells, polymer electrolyte membrane fuel cell (PEMFC) is known to be the most preferred for transportation systems and small stationary power generation equipment because the polymer electrolyte membrane fuel cell operates at a lower temperature than other fuels and the output density of the polymer electrolyte membrane fuel cell is high, thereby miniaturizing the polymer electrolyte membrane fuel cell.

[0007] One of the most important factors for improving the performance of polymer electrolyte membrane fuel cells (PEMFCs) is to supply a specified amount or more of water to the polymer electrolyte membrane or proton exchange membrane (PEM) of the membrane electrode assembly (MEA) to maintain the moisture content. The reason for this is that if the polymer electrolyte membrane or proton exchange membrane dries, the power generation efficiency is drastically reduced.

[0008] Methods used for humidifying polymer electrolyte membranes or proton exchange membranes include: 1) a bubbler humidification method, in which water is filled into a pressure vessel and the target gas is passed through a diffuser to supply moisture; 2) a direct injection method, in which the amount of moisture to be supplied required for the fuel cell reaction is calculated and the moisture is directly supplied to the gas flow conduit through a solenoid valve; and 3) a membrane humidification method, in which moisture is supplied to a gas fluidized bed using a polymer separation membrane.

[0009] Among these methods, the membrane humidification method uses a membrane configured to selectively allow only water vapor contained in the exhaust gas to pass through, and provides water vapor to the gas (i.e., air or fuel gas) supplied to the polymer electrolyte membrane or the proton exchange membrane to humidify the polymer electrolyte membrane or the proton exchange membrane. The advantage is that the weight and size of the humidifier can be reduced.

[0010] In the case of forming a module, a hollow fiber membrane having a large transmission area per unit volume is suitable for a selective permeable membrane used in a membrane humidification method. That is, when a humidifier is manufactured using a hollow fiber membrane, a high degree of integration of hollow fiber membranes having a large contact surface area can be achieved, whereby a polymer electrolyte membrane or a proton exchange membrane can be sufficiently humidified even in a small capacity, inexpensive materials can be used, and moisture and heat contained in exhaust gas discharged from a fuel cell at a high temperature can be collected, and the collected moisture and heat can be reused by the humidifier.

[0011] like Figure 1 As shown, a conventional membrane humidification type humidifier 1000 includes a humidifying module 1100 in which moisture is exchanged between gas supplied from the outside and exhaust gas exhausted from a fuel cell stack (not shown); and covers 1200 respectively coupled to opposite ends of the humidifying module 1100.

[0012] One of the covers 1200 transfers gas supplied from the outside to the humidifying module 1100 , and the other cover transfers the gas humidified by the humidifying module 1100 to the fuel cell stack.

[0013] The humidification module 1100 includes an intermediate housing 1110 having an exhaust gas inlet 1110a and an exhaust gas outlet 1110b, and a plurality of hollow fiber membranes 1120 disposed in the intermediate housing 1110. Opposite ends of a bundle of hollow fiber membranes 1120 are potted in a fixing layer 1130. Typically, each fixing layer 1130 is formed by hardening a liquid polymer such as a liquid polyurethane resin using a casting method such as dip casting (also called dip potting) or centrifugal casting (also called centrifugal potting).

[0014] The gas supplied from the outside flows along the hollow portion of the hollow fiber membrane 1120. The exhaust gas introduced into the intermediate housing 111 through the exhaust gas inlet 1110a contacts the outer surface of the hollow fiber membrane 1120 and is discharged from the intermediate housing 111 through the exhaust gas outlet 1110b. When the exhaust gas contacts the outer surface of the hollow fiber membrane 1120, moisture contained in the exhaust gas is transmitted through the hollow fiber membrane 1120 to humidify the gas flowing along the hollow portion of the hollow fiber membrane 1120.

[0015] The inner space of the cover 1200 must be in fluid communication with only the hollow portion of the hollow fiber membrane 1120 in a state completely isolated from the inner space of the intermediate housing 1110. Otherwise, gas leakage due to pressure difference may occur, thereby reducing power generation efficiency of the fuel cell.

[0016] Usually, if Figure 1 As shown, the fixing layer 1130 and the resin layer 1140 disposed between the fixing layer 1130 and the intermediate housing 1110 isolate the inner space of the cover 1200 from the inner space of the intermediate housing 1110. Similar to the fixing layer 1130, each resin layer 1140 is generally formed by hardening a liquid polymer such as a liquid polyurethane resin using a casting method (dip casting or centrifugal casting).

[0017] However, (i) due to repeated operation and stop of the fuel cell, the resin layer 1140 expands and contracts alternately, thereby separating the resin layer 1140 from the intermediate housing 1110 due to the difference in thermal expansion coefficient between the intermediate housing 1110 and the resin layer 1140, thereby generating a gap therebetween, or (ii) due to vibration and / or impact, there is a high probability that a gap will be generated between the resin layer 1140 and the intermediate housing 1110. The gap between the resin layer 1140 and the intermediate housing 1110 causes gas leakage, thereby reducing the power generation efficiency of the fuel cell.

[0018] In order to prevent gas leakage due to a gap generated between the resin layer 1140 and the intermediate shell 1110, Korean registered patent No. 1697998 discloses a method of applying a sealant (liquid seal) to a step formed on the side surface of the resin layer 1140 and a groove formed in the inner surface of the intermediate shell 1110, inserting a package (solid seal) into the groove, and curing the sealant.

[0019] However, the above method has problems of low productivity and high manufacturing cost in the following aspects: because (i) the sealant must be applied to precisely match the groove, thus having low workability, (ii) a considerable time of more than 24 hours is required for the sealant to harden, and (iii) a separate space for the humidification module 1100 needs to be reserved until the sealant hardens. Summary of the invention

[0020] Technical issues

[0021] Accordingly, the present disclosure is directed to a humidifier for a fuel cell and a method of manufacturing the same that can prevent the problems caused by the above-mentioned limitations and disadvantages of the related art.

[0022] An object of the present disclosure is to provide a humidifier for a fuel cell, which can reliably prevent gas leakage due to repeated operation and stop of the fuel cell and can be manufactured at a relatively low manufacturing cost and with high productivity.

[0023] Another object of the present disclosure is to provide a manufacturing method of a humidifier for a fuel cell, which can reliably prevent gas leakage caused by repeated operation and stop of the fuel cell at a relatively low manufacturing cost and high productivity.

[0024] In addition to the above-mentioned objects, other features and advantages of the present disclosure will be described hereinafter or will be clearly understood from the following description by those skilled in the art to which the present disclosure belongs.

[0025] Technical Solution

[0026] According to one aspect of the present disclosure, a humidifier for a fuel cell is provided, the humidifier comprising: a humidification module, the humidification module being configured to humidify gas supplied from the outside using moisture in exhaust gas exhausted from a fuel cell stack; and covers respectively coupled to opposite ends of the humidification module, wherein the humidification module comprises an intermediate shell opening at opposite ends, a plurality of hollow fiber membranes arranged in the intermediate shell, a fixing layer in which the ends of the hollow fiber membranes are potted, and a composite gasket having a groove for inserting the end of the intermediate shell, the composite gasket comprising: an internal body relative to the groove, the internal body being located inside the intermediate shell; an external body relative to the groove, the external body being located outside the intermediate shell; and a connector located between the internal body and the external body, the connector being formed of a first material, and at least a portion of the internal body being adhered to the fixing layer and being formed of a second material different from the first material.

[0027] The first material may be soft rubber, and the second material may be metal, hard plastic, hard rubber, or a soft rubber of a different type from the first material.

[0028] The first material may include soft silicone rubber or soft polyurethane rubber, and the second material may include polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polycarbonate (PC), acrylic resin, hard silicone rubber or hard polyurethane.

[0029] When the first material includes soft silicone rubber, the second material may include soft polyurethane rubber.

[0030] The inner body may include: a first portion directly connected to the connection body, the first portion being formed of a first material; and a second portion adhered to the first portion and the fixing layer, the second portion being formed of a second material.

[0031] The interface between the first portion and the second portion may have a step.

[0032] The first portion of the inner body may constitute a packaging portion formed of a first material together with the outer body and the connecting body, and the second portion of the inner body may constitute a bracket portion formed of a second material.

[0033] The packaging portion and the bracket portion may be integrally formed by injection molding.

[0034] The composite gasket may further include a primer layer formed on at least a portion of the surface of the inner body, the primer layer including a rubber adhesive component, an acrylic adhesive component, a polyurethane adhesive component, an epoxy adhesive component, a silicone adhesive component, a polyamide-based adhesive component, a polyimide-based adhesive component, or a mixture of two or more of the above.

[0035] The fixing layer may include: a first fixing layer in which the ends of the hollow fiber membranes are potted; and a second fixing layer that surrounds the first fixing layer while being adhered to an inner body of the composite gasket.

[0036] The first fixing layer and the second fixing layer may be formed of the same material.

[0037] The first fixing layer and the second fixing layer may both contain polyurethane (PU) resin.

[0038] The humidification module may further include an inner case disposed in the intermediate case, the inner case is opened at opposite ends thereof, the hollow fiber membrane may be disposed in the inner case, and the ends of the inner case may be potted in the first fixing layer.

[0039] The hollow fiber membrane may include a first group of hollow fiber membranes and a second group of hollow fiber membranes. The humidification module may further include: a first internal shell, in which the first group of hollow fiber membranes is arranged; and a second internal shell, in which the second group of hollow fiber membranes is arranged. The fixing layer may include: a first fixing layer, in which the ends of the first group of hollow fiber membranes are potted; a second fixing layer, in which the ends of the second group of hollow fiber membranes are potted; and a third fixing layer, which surrounds the first fixing layer and the second fixing layer and is adhered to the inner body of the composite gasket at the same time. The end of the first internal shell can be potted in the first fixing layer, and the end of the second internal shell can be potted in the second fixing layer.

[0040] According to another aspect of the present disclosure, a method for manufacturing a humidifier for a fuel cell is provided, the method comprising: preparing a hollow fiber membrane box having a first fixing layer, the ends of a plurality of hollow fibers being potted into the first fixing layer; inserting the hollow fiber membrane box into an intermediate shell opening at opposite ends thereof; preparing a composite gasket having a groove corresponding to the end of the intermediate shell; installing the composite gasket at the end of the intermediate shell so that the end of the intermediate shell is inserted into the groove; forming a second fixing layer, the second fixing layer being configured to fill the gap between the intermediate shell and the end of the hollow fiber membrane box and the composite gasket; The gap between the sheet and the end of the hollow fiber membrane box, and at the same time cutting the first fixing layer, the second fixing layer and the hollow fiber membrane to make the end of the hollow fiber membrane open; and fastening the cover to the intermediate shell so that the composite gasket is pressed by the cover, wherein the composite gasket includes: an inner body relative to the groove, the inner body is located in the intermediate shell based on the groove; an outer body relative to the groove, the outer body is located outside the intermediate shell; and a connector, the connector is located between the inner body and the outer body, the connector is formed of a first material, and at least a portion of the inner body is formed of a second material different from the first material.

[0041] The inner body may include: a first portion directly connected to the connection body, the first portion being formed of a first material; and a second portion adhered to the first portion and the fixing layer, the second portion being formed of a second material.

[0042] The first portion of the inner body may constitute a packaging portion formed of a first material together with the outer body and the connecting body, and the second portion of the inner body may constitute a bracket portion formed of a second material.

[0043] The preparation of the composite gasket may include: preparing a bracket portion; inserting the bracket portion into a mold; injecting a melt of a first material into the mold where the bracket portion is located; and cooling the melt of the first material to obtain a packaging portion adhered to the bracket portion.

[0044] Alternatively, the preparation of the composite gasket may include performing co-injection molding to simultaneously form the bracket portion and the encapsulation portion.

[0045] The preparation of the hollow fiber membrane cassette may include: inserting at least a portion of each hollow fiber membrane into an inner case; and performing a dip casting process or a centrifugal casting process to form a first fixing layer.

[0046] When the dip casting process or the centrifugal casting process is performed, the end of the inner case may also be encapsulated in the first fixing layer together with the end of the hollow fiber membrane.

[0047] The general description of the present disclosure given above is only used to illustrate or describe the present disclosure, and does not limit the scope of the rights of the present disclosure.

[0048] Beneficial Effects

[0049] According to the present disclosure, it is possible to effectively prevent external leakage and internal leakage only by mechanical assembly of the composite gasket without the conventional sealant coating process and curing process. Therefore, according to the present disclosure, the processability is improved and the manufacturing time is reduced, thereby significantly improving its productivity because the sealant coating process and the sealant curing process required in the conventional technology are omitted.

[0050] Furthermore, a separate space for storing semi-finished products of the sealant curing process is not required, whereby the production cost of the humidifier can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The accompanying drawings, which are included to help the understanding of the present disclosure and are included in and constitute a part of this specification, illustrate embodiments of the present disclosure and serve to explain the principles of the present disclosure together with the detailed description of the present disclosure.

[0052] Figure 1 is an exploded perspective view of a conventional humidifier for a fuel cell;

[0053] Figure 2 is a cross-sectional view of a humidifier according to a first embodiment of the present disclosure;

[0054] Figure 3 (a) is a perspective view of a composite gasket according to an embodiment of the present disclosure;

[0055] Figure 3 (b) is along Figure 3 (a) a cross-sectional view taken along line AA;

[0056] Figure 4 (a) to Figure 4 (f) is a cross-sectional view of a composite gasket according to various embodiments of the present disclosure;

[0057] Figure 5 is a cross-sectional view of a humidifier according to a second embodiment of the present disclosure;

[0058] Figure 6 is a cross-sectional view of a humidifier according to a third embodiment of the present disclosure; and

[0059] Figures 7a to 7f is a cross-sectional view explaining a method of manufacturing a humidifier according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0060] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. However, the following embodiments are only exemplarily provided for clear understanding of the present disclosure and do not limit the scope of the present disclosure.

[0061] Figure 2, Figure 5 , Figure 6 and Figures 7a to 7f is a cross-sectional view showing one end of a humidifier or a semi-finished product, the other end of the humidifier or the semi-finished product having a substantially identical (or symmetrical) cross-section.

[0062] like Figure 2 As shown, a humidifier 2000 for a fuel cell according to the present disclosure includes a humidification module 2100 configured to humidify gas supplied from the outside using moisture in exhaust gas exhausted from a fuel cell stack. Opposite ends of the humidification module 2100 are respectively coupled to covers 2200.

[0063] One of the covers 2200 receives gas from the outside through the port 2210 and transmits the gas to the humidification module 2100, and the other cover transmits the gas humidified by the humidification module 2100 to the fuel cell stack through the port 2210. Each cover 2200 may be formed of a rigid plastic (e.g., polycarbonate, polyamide (PA), or polyphthalamide (PPA)) or metal, and may have a cross-section of a simple closed curve shape (e.g., a circle or a polygon).

[0064] In a humidification module 2100 according to an embodiment of the present disclosure, moisture exchange is performed between gas supplied from the outside and exhaust gas supplied from a fuel cell stack, and the humidification module 2100 according to an embodiment of the present disclosure includes: an intermediate shell 2110 opened at opposite ends thereof, a plurality of hollow fiber membranes 2121 being arranged in the intermediate shell 2110; a fixing layer 2122, in which ends of the hollow fiber membranes 2121 are encapsulated; and a composite gasket 2130 having a groove, into which ends of the intermediate shell 2110 are inserted.

[0065] The intermediate housing 2110 has a port 2111 for exhaust gas introduction / discharge ( Figure 2 Only one is shown in the figure). The intermediate housing 2110 may be formed of a rigid plastic (e.g., polycarbonate, polyamide (PA), or polyphthalamide (PPA)) or a metal, and may have a cross-section of a simple closed curve shape (e.g., a circle or a polygon). According to an embodiment of the present disclosure, the intermediate housing 2110 may have the same cross-section as the cover 2200.

[0066] Each hollow fiber membrane 2121 may include a polymer membrane formed of polysulfone resin, polyethersulfone resin, sulfonated polysulfone resin, polyvinylidene fluoride (PVDF) resin, polyacrylonitrile (PAN) resin, polyimide resin, polyamideimide resin, polyesterimide resin, or a mixture of two or more thereof.

[0067] The gas supplied from the outside through one cover 2200 is humidified while flowing along the hollow portion of the hollow fiber membrane 2121 , and is transferred to the fuel cell stack through the other cover 2200 .

[0068] The exhaust gas introduced into the intermediate housing 2110 contacts the outer surface of the hollow fiber membrane 2121 and is discharged from the intermediate housing 211. When the exhaust gas contacts the outer surface of the hollow fiber membrane 2121, moisture contained in the exhaust gas is transmitted through the hollow fiber membrane 2121 to humidify the gas flowing along the hollow portion of the hollow fiber membrane 2121.

[0069] The fixing layer 2122 may be formed of hard or soft polyurethane resin, and must isolate the inner space of the cover 2200 from the inner space of the intermediate housing 2110 so that the cover 2200 is in fluid communication only with the hollow fiber membranes 2121 .

[0070] However, as described above, (i) the fixing layer 2122 alternately expands and contracts due to repeated operation and stop of the fuel cell, thereby separating the fixing layer 2122 from the intermediate shell 2110 due to the difference in thermal expansion coefficient between the intermediate shell 2110 and the fixing layer 2122, thereby generating a gap therebetween, or (ii) due to vibration and / or impact, there is a high probability that a gap will be generated between the fixing layer 2122 and the intermediate shell 2110. The gap between the fixing layer 2122 and the intermediate shell 1110 causes gas leakage, thereby reducing the power generation efficiency of the fuel cell.

[0071] Gas leakage that may be caused by the generation of a gap between the fixed layer 2122 and the intermediate shell 2110 includes: (i) external leakage, through which the exhaust gas in the internal space of the intermediate shell 2110 passes through the gap between the fixed layer 2122 and the intermediate shell 2110 and the gap between the cover 2200 and the intermediate shell 2110 in sequence, and is then discharged to the outside of the humidifier 2000; and (ii) internal leakage, through which the exhaust gas in the internal space of the intermediate shell 2110 passes through the gap between the fixed layer 2122 and the intermediate shell 2110 and the gap between the fixed layer 2122 and the cover 2200 in sequence, and is then introduced into the internal space of the cover 2200.

[0072] In order to prevent gas leakage due to generation of a gap between the fixing layer 2122 and the intermediate case 2110 , the humidifier 2000 for a fuel cell according to the present disclosure further includes a composite gasket 2130 .

[0073] like Figure 3 As shown in FIG. 2A , the composite gasket 2130 may have a simple closed curve shape corresponding to the cross-section of the intermediate shell 2110 .

[0074] like Figure 3 As shown in (b), Figure 3 (b) is along Figure 3 (a) is a sectional view taken along line AA, the composite gasket 2130 may have a groove G, into which the end of the intermediate shell 2110 is inserted, and the composite gasket 2130 may include a packaging portion 2131 and a bracket portion 2132, which are formed of different materials.

[0075] Figure 4 (a) to Figure 4 (f) is a cross-sectional view of a composite gasket 2130 according to various embodiments of the present disclosure.

[0076] refer to Figure 4 (a) to Figure 4 (c) According to the composite gasket 2130 disclosed herein, the composite gasket 2130 includes: an inner body 2130a relative to a groove G into which the end of the intermediate shell 2110 is inserted, the inner body 2130a being located inside the intermediate shell 2110; an outer body 2130b relative to the groove G, the outer body 2130b being located outside the intermediate shell 2110; and a connector 2130c located between the inner body 2130a and the outer body 2130b, the connector being formed of a first material.

[0077] According to the present disclosure, at least a portion of the inner body 2130a is formed of a second material different from the first material.

[0078] According to an embodiment of the present disclosure, the second material may be a material that exhibits higher adhesive force with respect to the fixing layer 2122 than the first material, and a portion of the inner body 2130 a formed of the second material may be firmly bonded to the fixing layer 2122 .

[0079] For example, the connector 2130c of the composite gasket 2130 may be formed of a first material (e.g., soft rubber) having a relatively low hardness of 30 to 60 Shore A, more preferably 40 to 50 Shore A, so as to be compressed by the pressure applied when the cover 2200 is fastened to the intermediate housing 2110 by bolts 2310 and nuts 2320, and the portion of the inner body 2130a that is in direct contact with the fixing layer 2122 may be formed of a material (e.g., metal, hard plastic, hard rubber, or soft rubber) that exhibits higher adhesion to the fixing layer 2122 than the first material.

[0080] The first material of the connector 2130c may include soft silicone rubber or soft polyurethane rubber, and the second material of the inner body 2130a may include polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polycarbonate (PC), acrylic resin, hard silicone or hard polyurethane.

[0081] In addition, when the first material of the connector 2130c includes soft silicone rubber, the second material of the inner body 2130a may include soft polyurethane rubber.

[0082] Respectively Figure 4 (a) to Figure 4 As shown in (c), the inner body 2130a may include: (i) a first portion directly connected to the connector 2130c and formed of a first material; and (ii) a second portion adhered to the first portion and the fixing layer 2122, and formed of a second material.

[0083] In order to increase the contact area between the first part and the second part formed of different materials, thereby maximizing the adhesion therebetween, the interface between the first part and the second part may have a step, such as Figure 4 (a) and Figure 4 (b) as shown.

[0084] The first part of the inner body 2130a can constitute a packaging part 2131 formed of a first material together with the outer body 2130b and the connector 2130c. The second part of the inner body 2130a can constitute a bracket part 2132 formed of a second material. The packaging part 2131 and the bracket part 2132 can be integrally formed by injection molding, which will be described in detail below.

[0085] When the cover 2200 is fastened to the intermediate shell 2110 by bolts 2310 and nuts 2320, the connector 2130c of the composite gasket 2130 is pressed and clamped by the end of the intermediate shell 2110 and the cover 2200, thereby preventing gas from moving through the interface between the composite gasket 2130 and the intermediate shell 2110 (i.e., external leakage), thereby ensuring a tight external seal.

[0086] In addition, since the packaging part 2131 and the bracket part 2132 are integrally formed by injection molding, a strong adhesive force can be obtained between them. Therefore, it is possible to prevent gas from moving through the interface between the packaging part 2131 and the bracket part 2132 (i.e., through the interface between the first part and the second part of the internal body 2130a) (i.e., internal leakage), so that a good internal seal can be ensured.

[0087] In addition, since the bracket portion 2132 (i.e., the second part of the internal body 2130a) according to an embodiment of the present disclosure has excellent adhesion relative to the fixing layer 2122, the gas can be prevented from moving through the interface between the bracket portion 2132 and the fixing layer 2122 (i.e., internal leakage), thereby providing a stronger internal seal.

[0088] Optionally, the surface of the bracket portion 2132 or the surface of the inner body 2130a may be treated with a primer, thereby further increasing the bonding strength between the bracket portion 2132 or the inner body 2130a and the fixing layer 2122, thereby maximizing the internal sealing effect. Figure 4 (d) to Figure 4 As shown in (f), the composite gasket 2130 according to the present disclosure further includes a primer layer 2133 formed on at least a portion of the surface of the inner body 2130a, whereby the composite gasket can have a stronger adhesive force relative to the fixing layer 2122. The primer used to increase the adhesive strength between the composite gasket 2130 and the fixing layer 2122 may include a rubber adhesive component, an acrylic adhesive component, a polyurethane adhesive component, an epoxy adhesive component, a silicone adhesive component, a polyamide-based adhesive component, a polyimide-based adhesive component, or a mixture of two or more of the foregoing components.

[0089] For the rubber adhesive component, natural rubber (NR) and / or synthetic rubber may be used. The synthetic rubber may be SBR, NBR, CR, BR, IIR and / or EPDM.

[0090] For the acrylic adhesive component, acrylic emulsions, anaerobic acrylic resins, and / or acrylic resin-based tapes may be used.

[0091] For the polyurethane adhesive component, solvent-based polyurethane, polyurethane hot melt, or urethane emulsion may be used.

[0092] For the polyamide-based adhesive component, a polyamide hot melt adhesive may be used.

[0093] like Figure 2 As shown, the cover 2200 according to an embodiment of the present disclosure may have a protrusion 2220 formed at a position corresponding to the end of the intermediate housing 2110 inserted into the groove G of the composite gasket 2130. The protrusion 2220, together with the end of the intermediate housing 2110, more effectively compresses the connector 2130c of the composite gasket 2130, thereby achieving a tighter external seal.

[0094] like Figure 2As shown, in addition to the second portion of the inner body 2130a of the composite gasket 2130, the first portion of the inner body 2130a of the composite gasket 2130 may also be adhered to the fixing layer 2122. The liquid resin (e.g., liquid polyurethane resin) used to form the fixing layer 2122 is hardened in a state of contact with the first and second portions of the inner body 2130a of the composite gasket 2130, thereby increasing the bonding strength between the gasket 2130 and the fixing layer 2122, thereby improving the internal sealing.

[0095] According to the embodiments of the present disclosure, Figure 2 As shown, the fixing layer 2122 may include: a first fixing layer 2122-1 in which the end of the hollow fiber membrane 2121 is potted; and a second fixing layer 2122-2 which surrounds the first fixing layer 2122-1 and adheres to the inner body 2130a of the composite gasket 2130.

[0096] Each of the first fixing layer 2122-1 and the second fixing layer 2122-2 can be formed by hardening a liquid resin such as a liquid polyurethane resin using a dip casting method or a centrifugal casting method. Although the first fixing layer 2122-1 and the second fixing layer 2122-2 can be formed of different materials, considering the bonding strength therebetween, preferably, the first fixing layer and the second fixing layer are formed of the same material (e.g., polyurethane resin).

[0097] like Figure 2 As shown, the humidification module 2100 may further include an inner shell 2123 disposed in the intermediate shell 2110, the inner shell being open at opposite ends thereof. In this case, the hollow fiber membrane 2121 is disposed in the inner shell 2123. The first fixing layer 2122-1 in which the ends of the hollow fiber membrane 2121 are potted closes a corresponding one of the open ends of the inner shell 2123.

[0098] According to an embodiment of the present disclosure, the inner housing 2123 has a plurality of holes H ( Figure 2 Only one is shown in the figure). The exhaust gas introduced into the intermediate housing 2110 through the first port 2111 passes through the first hole H and then absorbs moisture while flowing along the outer surface of the hollow fiber membrane 2121. Subsequently, the exhaust gas is discharged from the inner housing 2123 through the second hole H on the opposite side and then discharged from the intermediate housing 2110 through the second port 2111.

[0099] The hollow fiber membrane 2121 , the first fixing layer 2122 - 1 and the inner shell 2123 constitute a hollow fiber membrane box 2120 .

[0100] like Figure 2 As shown, the end of the inner shell 2123 is encapsulated in the first fixing layer 2122 - 1 , thereby the relative positions of the hollow fiber membranes 2121 and the inner shell 2123 can be uniformly maintained.

[0101] In the following, reference will be made to Figure 5 A humidifier 2000 for a fuel cell according to a second embodiment of the present disclosure is described.

[0102] A humidifier 2000 for a fuel cell according to a second embodiment of the present disclosure is Figure 2 The humidifier 2000 for a fuel cell is the same as the humidifier 2000 for a fuel cell, except that the intermediate housing 2110 has a step 2112 formed on an inner circumferential surface thereof and the composite gasket 2130 (more specifically, the bracket portion 2132 ) is supported by the step 2112 .

[0103] Since the bracket portion 2132 is supported by the step 2112 of the intermediate housing 2110 and has a higher hardness than the packaging portion 2131, when the cover 2200 is fastened to the intermediate housing 2110 by the bolts 2310 and the nuts 2320, the bracket portion 2132 can effectively apply pressure to the packaging portion 2131 together with the cover 2200. Therefore, it is possible to prevent gas from moving through the interface between the packaging portion 2131 and the bracket portion 2132 (i.e., through the interface between the first portion and the second portion of the inner body 2130a) (i.e., internal leakage), and thus good internal sealing can be ensured.

[0104] In addition, if Figure 4 As shown in (f), when at least a portion of the surface of the inner body 2130a of the composite gasket 2130 is treated with a primer, not only the surface of the inner body is in contact with the fixing layer 2122, but also the surface of the inner body supported by the step 2112 is treated with a primer, thereby further increasing the bonding strength between the inner body 2130a and the fixing layer 2122, thereby maximizing the internal sealing effect. Furthermore, the bonding strength between the inner body 2130a and the step 2112 can be further increased, thereby maximizing the external sealing effect.

[0105] In the following, reference will be made to Figure 6 A humidifier 2000 for a fuel cell according to a third embodiment of the present disclosure is described.

[0106] like Figure 6 As shown, a humidifier 2000 for a fuel cell according to a third embodiment of the present disclosure is substantially the same as the first embodiment described above, except that the humidifier includes two hollow fiber membrane cartridges 2120a and 2120b.

[0107] That is, according to the third embodiment of the present disclosure, the hollow fiber membrane includes a first group of hollow fiber membranes 2121a and a second group of hollow fiber membranes 2121b, and the humidification module 2100 includes: a first internal shell 2123a, in which the first group of hollow fiber membranes 2121a are disposed; and a second internal shell 2123b, in which the second group of hollow fiber membranes 2121b are disposed, and the fixing layer 2122 includes: a first fixing layer 2123a; 2-1a, the ends of the first group of hollow fiber membranes 2121a are embedded in the first fixing layer 2122-1a; the second fixing layer 2122-1b, the ends of the second group of hollow fiber membranes 2121b are embedded in the second fixing layer 2122-1b; and the third fixing layer 2122-2, the third fixing layer 2122-2 surrounds the first fixing layer 2122-1a and the second fixing layer 2122-1b and is adhered to the inner body 2130a of the composite gasket 2130.

[0108] The first group of hollow fiber membranes 2121a, the first fixing layer 2122-1a and the first inner shell 2123a constitute a first hollow fiber membrane cassette 2120a, and the second group of hollow fiber membranes 2121b, the second fixing layer 2122-1b and the second inner shell 2123b constitute a second hollow fiber membrane cassette 2120b.

[0109] like Figure 6 As shown, the ends of the first internal shell 2123a and the second internal shell 2123b are respectively encapsulated in the first fixed layer 2122-1a and 2122-1b, so that the relative position of the first group of hollow fiber membranes 2121a and the first internal shell 2123a and the relative position of the second group of hollow fiber membranes 2121b and the second internal shell 2123b can be evenly maintained.

[0110] In order to improve the humidification capacity, it is necessary to increase the number of hollow fiber membranes 2121. However, in the first and second embodiments, each embodiment includes only a single hollow fiber membrane box 2120, and there is a problem that if the number of hollow fiber membranes 2121 increases, it is difficult to transmit the exhaust gas to the hollow fiber membrane 2121 located in the center.

[0111] In contrast, in the third embodiment of the present disclosure, the two hollow fiber membrane boxes 2120a and 2120b are spaced apart from each other, whereby even if the number of hollow fiber membranes 2121a and 2121b increases, the exhaust gas can be relatively uniformly transmitted to the hollow fiber membranes 2121a and 2121b. That is, assuming that the number of hollow fiber membranes is equal, the structure of the third embodiment including two hollow fiber membrane boxes 2120a and 2120b is advantageous in terms of utilization of the hollow fiber membranes, compared with the structures of the first and second embodiments each including a single hollow fiber membrane box 2120.

[0112] The number of hollow fiber membrane cartridges installed in the intermediate housing 2110 may be determined by comprehensively considering the capacity of the fuel cell (or the required humidification capacity), the size of the humidifier, and the weight of the humidifier.

[0113] In the following, reference will be made to Figures 7a to 7f The manufacturing method of the humidifier 2000 for a fuel cell according to an embodiment of the present disclosure is described in more detail.

[0114] First, if Figure 7a As shown, a hollow fiber membrane cassette 2120 ′ having a first fixing layer 2122 - 1 ′ is prepared, and ends of a plurality of hollow fiber membranes 2121 ′ are potted in the first fixing layer 2122 - 1 ′.

[0115] The hollow fiber membrane box 2120' can be manufactured by inserting at least a portion of each hollow fiber membrane 2121' into the inner shell 2123 and performing a dip casting process or a centrifugal casting process using a liquid resin such as a liquid polyurethane resin. The first fixing layer 2122-1' in which the end of the hollow fiber membrane 2121' is potted is formed due to the hardening of the liquid resin.

[0116] When the dip casting process or the centrifugal casting process is performed, the end of the inner case 2123 may be potted in the first fixing layer 2122 - 1 ′ together with the end of the hollow fiber membrane 2121 ′.

[0117] The inner housing 2123 may have a first group of holes H and a second group of holes H formed in a longitudinal direction thereof so as to be located at opposite sides.

[0118] Then, if Figure 7b As shown, the hollow fiber membrane cassette 2120' is inserted into the intermediate housing 2110 which is open at opposite ends thereof.

[0119] According to an embodiment of the present disclosure, the intermediate housing 2110 has a simple closed curve-shaped cross section. The intermediate housing 2110 may have a partition wall configured to partition its internal space into an exhaust gas introduction space and an exhaust gas discharge space located on opposite sides in the longitudinal direction, and the hollow fiber membrane box 2120' may be inserted through a hole formed in the partition wall to be supported by the partition wall. At this time, the first group of holes H of the internal housing 2123 is located in the exhaust gas introduction space, and the second group of holes H of the internal housing 2123 is located in the exhaust gas discharge space.

[0120] In this case, the exhaust gas that has entered the exhaust gas introduction space is introduced into the internal shell 2123 through the first group of holes H, flows to the second group of holes H in the internal shell 2123, moves to the exhaust gas discharge space through the second group of holes H, and is discharged from the intermediate shell 2110.

[0121] Then, if Figure 7c As shown, a composite gasket 2130 having a groove G corresponding to the end of the intermediate shell 2110 is prepared, and the composite gasket 2130 is installed on the end of the intermediate shell 2110 so that the end of the intermediate shell 2110 is inserted into the groove G.

[0122] The composite gasket 2130 can be obtained by the following processes: (i) preparing a bracket portion 2132 formed of a second material, (ii) inserting the bracket portion 2132 into a mold, (iii) injecting a melt of the first material into the mold where the bracket portion 2132 is located, and (iv) cooling the melt of the first material to obtain the encapsulation portion 2131 adhered to the bracket portion 2132. Optionally, the surface of the bracket portion 2132 may be treated with a primer and may be inserted into the mold afterwards to increase the bonding strength between the bracket portion 2132 and the encapsulation portion 2131.

[0123] Alternatively, co-injection molding may be performed to simultaneously form the support portion 2132 and the packaging portion 2131 .

[0124] As described above, at least a portion of the surface of the inner body 2130a of the composite gasket 2130 obtained through the above process may be treated with a primer.

[0125] According to an embodiment of the present disclosure, the packaging part 2131 and the bracket part 2132 are integrally formed by injection molding, thereby obtaining a strong adhesive force between the packaging part and the bracket part even if they are formed of different materials. Therefore, it is possible to prevent gas from moving through the interface between the packaging part 2131 and the bracket part 2132 (i.e., internal leakage), thereby ensuring a good internal seal.

[0126] Then, if Figure 7d As shown, a second fixing layer 2122 - 2 ′ is formed, and the second fixing layer 2122 - 2 ′ is configured to fill a gap between an end of the hollow fiber membrane cassette 2120 ′ and the intermediate housing 2110 and a gap between an end of the hollow fiber membrane cassette 2120 ′ and the composite gasket 2130 .

[0127] The second fixing layer 2122-2' may be manufactured by fastening a potting cap (not shown) to the intermediate housing 2110, performing a dip-casting process of injecting a liquid resin such as a liquid polyurethane resin into the potting cap and hardening the liquid resin in a state where the potting cap is located below the intermediate housing 2110, and removing the potting cap. Alternatively, the second fixing layer 2122-2' may be formed by a centrifugal casting process.

[0128] Although the first fixing layer 2122-1' and the second fixing layer 2122-2' may be formed of different liquid resins, in consideration of the adhesive strength therebetween, preferably, the first fixing layer and the second fixing layer are formed of the same material (eg, polyurethane resin).

[0129] According to an embodiment of the present disclosure, the liquid resin (e.g., liquid polyurethane resin) used to form the second fixing layer 2122-2' can be hardened while in contact with the composite gasket 2130 (specifically, the bracket portion), thereby increasing the bonding strength of the second fixing layer 2122-2' therewith, thereby improving the internal sealing.

[0130] According to an embodiment of the present disclosure, since the bracket portion 2132 is formed of a material having excellent adhesion to the second fixed layer 2122-2', the movement of gas through the interface between them (i.e., internal leakage) can be prevented, and thus a stronger internal seal can be provided. In addition, when the surface of the bracket portion 2132 is treated with a primer, as described above, the bonding strength between the bracket portion 2132 and the second fixed layer 2122-2' can be maximized, and thus a better internal seal can be provided.

[0131] Subsequently, the first fixing layer 2122-1', the second fixing layer 2122-2' and the hollow fiber membrane 2121' are simultaneously cut along the cutting line CL of Figure 7D, thereby obtaining the hollow fiber membrane 2121, as shown in Figure 7E, which is configured so that its end embedded in the first fixing layer 2122-1 surrounded by the second fixing layer 2122-2 is open.

[0132] Then, if Figure 7f As shown, the cover 2200 is fastened to the intermediate housing 2110 such that the connecting body 2130 c of the composite gasket 2130 is compressed by the cover 2200 .

[0133] like Figure 7f As shown, the cover 2200 according to an embodiment of the present disclosure may have a protrusion 2220 formed at a position corresponding to the end of the intermediate housing 2110. Since the end of the intermediate housing 2110 is inserted into the groove G of the composite gasket 2130, the protrusion 2220 and the end of the intermediate housing 2110 together compress the connector 2130c of the composite gasket 2130, thereby achieving a tighter external seal.

[0134] According to the above-mentioned disclosure, it is possible to effectively prevent external leakage and internal leakage only by mechanical assembly of the composite gasket 2130 without the need for conventional sealant coating process and curing process. Therefore, according to the disclosure, the workability is improved and the manufacturing time is reduced, thereby significantly improving its productivity because the sealant coating process and the sealant hardening process required in the prior art are omitted. In addition, a separate space for storing semi-finished products in the sealant hardening process is not required, thereby reducing the production cost of the humidifier.

Claims

1. A humidifier for a fuel cell, the humidifier comprising: a humidification module configured to humidify gas supplied from the outside using moisture in exhaust gas exhausted from the fuel cell stack; as well as covers, the covers being respectively coupled to opposite ends of the humidification module, Wherein, the humidification module comprises: an intermediate housing open at opposite ends of the intermediate housing; a plurality of hollow fiber membranes disposed in the intermediate housing; a fixing layer in which ends of the hollow fiber membranes are potted; and a composite gasket having a groove into which the end of the intermediate housing is inserted, The composite gasket comprises: Relative to the inner body of the groove, the inner body is located inside the intermediate housing; The outer body is located outside the intermediate housing relative to the outer body of the groove; and a connecting body between the inner body and the outer body, the connecting body being formed of a first material, and At least a portion of the inner body is adhered to the securing layer and is formed of a second material different from the first material.

2. The humidifier according to claim 1, wherein: The first material has a hardness of 30 Shore A to 60 Shore A, and The second material has a higher adhesive force with respect to the fixing layer than the first material.

3. The humidifier according to claim 1, wherein: The first material comprises soft silicone rubber or soft polyurethane rubber, and The second material includes polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polycarbonate (PC), acrylic resin, hard silicone rubber or hard polyurethane.

4. The humidifier according to claim 1, wherein: The first material comprises soft silicone rubber, and The second material includes soft polyurethane rubber.

5. The humidifier according to claim 1, wherein: The internal body comprises: directly connected to a first portion of the connector, the first portion being formed of the first material; and Adhering to the first portion and a second portion of the fixing layer, the second portion is formed of the second material.

6. The humidifier according to claim 5, wherein: An interface between the first portion and the second portion has a step.

7. The humidifier according to claim 5, wherein: The first portion of the inner body, together with the outer body and the connecting body, constitutes a packaging portion formed of the first material. The second portion of the inner body constitutes a bracket portion formed of the second material, and The encapsulation part and the bracket part are integrally formed by injecting a melt of the first material into a mold where the bracket part is located and cooling the melt of the first material to obtain the encapsulation part adhered to the bracket part, or performing co-injection molding to simultaneously form the bracket part and the encapsulation part.

8. The humidifier according to claim 5, wherein: The first portion of the inner body, together with the outer body and the connecting body, constitutes a packaging portion formed of the first material. the second portion of the inner body constituting a bracket portion formed of the second material, The intermediate housing has a step formed on an inner circumferential surface of the intermediate housing, The bracket portion is supported by the step, and The bracket portion has a higher hardness than the packaging portion.

9. The humidifier according to claim 1, wherein: The composite gasket further includes a primer layer formed on at least a portion of the surface of the inner body, the primer layer including a rubber adhesive component, an acrylic adhesive component, a polyurethane adhesive component, an epoxy adhesive component, a silicone adhesive component, a polyamide-based adhesive component, a polyimide-based adhesive component, or a mixture of two or more of the above.

10. The humidifier according to claim 1, wherein: The fixed layer comprises: a first fixing layer in which the end portions of the hollow fiber membranes are potted; and A second fixing layer surrounds the first fixing layer while being adhered to the inner body of the composite gasket.

11. The humidifier according to claim 10, wherein: The first fixing layer and the second fixing layer are formed of the same material.

12. The humidifier according to claim 10, wherein: The first fixing layer and the second fixing layer both include polyurethane (PU) resin.

13. The humidifier according to claim 10, wherein: The humidification module further includes an inner shell disposed in the intermediate shell, the inner shell being open at opposite ends, The hollow fiber membrane is disposed in the inner housing, and The end of the inner shell is potted in the first fixing layer.

14. The humidifier according to claim 1, wherein: The hollow fiber membranes include a first group of hollow fiber membranes and a second group of hollow fiber membranes, The humidification module further comprises: a first internal shell in which the first set of hollow fiber membranes is disposed; and a second inner shell, wherein the second set of hollow fiber membranes is disposed in the second inner shell, The fixed layer comprises: a first fixing layer, in which ends of the first group of hollow fiber membranes are potted; a second fixing layer in which ends of the second group of hollow fiber membranes are potted; and a third fixing layer, the third fixing layer surrounding the first fixing layer and the second fixing layer while being adhered to the inner body of the composite gasket, The end of the first inner shell is potted in the first fixing layer, and An end portion of the second inner shell is potted in the second fixing layer.

15. A method for manufacturing a humidifier for a fuel cell, the method comprising: preparing a hollow fiber membrane box having a first fixing layer, wherein ends of a plurality of hollow fibers are potted into the first fixing layer; inserting the hollow fiber membrane cassette into an intermediate housing, opening at opposite ends of the intermediate housing; preparing a composite gasket having a groove corresponding to the end of the intermediate housing; installing the composite gasket on the end of the intermediate housing so that the end of the intermediate housing is inserted into the groove; forming a second fixing layer configured to fill a gap between the intermediate housing and an end of the hollow fiber membrane box and a gap between the composite gasket and the end of the hollow fiber membrane box; cutting the first fixing layer, the second fixing layer and the hollow fiber membrane simultaneously so that the end of the hollow fiber membrane is opened; as well as The cover is fastened to the intermediate housing so that the composite gasket is compressed by the cover, wherein: The composite gasket comprises: Relative to the inner body of the groove, the inner body is located inside the intermediate housing; The outer body is located outside the intermediate housing relative to the outer body of the groove; and a connector, the connector being located between the inner body and the outer body, the connector being formed of a first material, and At least a portion of the inner body is formed from a second material different than the first material.

16. The humidifier according to claim 15, wherein: The first material has a hardness of 30 Shore A to 60 Shore A, and The second material has a higher adhesive force with respect to the second fixing layer than the first material.

17. The method according to claim 15, wherein: The internal body comprises: a first portion, the first portion being directly connected to the connector; and a second part, the second part being adhered to the first part and the fixing layer, The first part of the inner body, the outer body and the connector together form a packaging part formed of the first material, and Wherein, the second portion of the inner body constitutes a bracket portion formed of the second material.

18. The method according to claim 17, wherein: The intermediate housing has a step formed on an inner circumferential surface of the intermediate housing, wherein the composite gasket is mounted on the end of the intermediate housing so that the bracket portion is supported by the step, and The bracket portion has a higher hardness than the packaging portion.

19. The method according to claim 15, wherein: The preparation of the hollow fiber membrane box comprises: inserting at least a portion of each of the hollow fiber membranes into an inner housing; and A dip casting process or a centrifugal casting process is performed to form the first fixed layer.

20. The method according to claim 19, wherein: When the dip casting process or the centrifugal casting process is performed, the end of the inner case is also potted in the first fixing layer together with the end of the hollow fiber membrane.

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