Fuel cell membrane humidifier

Abstract

The present invention relates to a fuel cell membrane humidifier that can prevent gas leakage caused by repeated operation and shutdown of a fuel cell, can be manufactured at relatively low manufacturing costs and with high productivity, and can suppress vibrations generated during operation. The fuel cell membrane humidifier according to an embodiment of the present invention comprises: The humidification module includes a humidification module that humidifies air supplied from the outside with moisture in exhaust gas discharged from a fuel cell stack, and caps that are respectively coupled to both ends of the humidification module. The humidification module includes a mid-case with both ends open and a step formed on an inner circumferential surface, at least one cartridge that is disposed in the mid-case and accommodates a plurality of hollow fiber membranes, a fixing layer on which the ends of the hollow fiber membranes are potted and supported by the inner wall of the mid-case, a bracket that is supported by the step of the mid-case and contacts the fixing layer, and a packing member that has a groove into which the end of the mid-case is sandwiched and contacts the bracket. The humidification module also includes a damping protrusion formed on the inner wall of the mid-case that is sandwiched between the fixing layer and suppresses vibrations generated in the cartridge due to air flowing inside the humidification module.

Description

[Technical field]

[0001] The present invention relates to a fuel cell membrane humidifier, and more particularly, to a fuel cell membrane humidifier that can prevent gas leakage caused by repeated operation and shutdown of a fuel cell, can be manufactured at relatively low manufacturing costs and with high productivity, and can suppress vibrations that occur during operation. [Background technology]

[0002] A fuel cell is a power generating battery that produces electricity by combining hydrogen and oxygen. Unlike ordinary chemical batteries such as dry batteries and storage batteries, fuel cells can continue to produce electricity as long as hydrogen and oxygen are supplied, and because there is no heat loss, they have the advantage of being about twice as efficient as internal combustion engines. In addition, fuel cells emit less pollutants because they directly convert the chemical energy generated by the combination of hydrogen and oxygen into electrical energy, making them environmentally friendly and reducing concerns about resource depletion due to increased energy consumption.

[0003] Depending on the type of electrolyte used, such fuel cells can be broadly classified into polymer electrolyte membrane fuel cells (PEMFCs), phosphoric acid fuel cells (PAFCs), molten carbonate fuel cells (MCFCs), solid oxide fuel cells (SOFCs), alkaline fuel cells (AFCs), and the like.

[0004] Although all of these fuel cells operate on the same principle, they differ in the type of fuel used, operating temperature, catalyst, electrolyte, etc. Among them, polymer electrolyte membrane fuel cells (PEMFCs) are known to be the most promising for use in small-scale stationary power generation equipment as well as transportation systems, as they operate at lower temperatures than other fuel cells, have a high power density, and can be made compact. One of the most important factors in improving the performance of a polymer electrolyte fuel cell (PEMFC) is to maintain the moisture content by supplying a certain amount of moisture to the polymer electrolyte membrane (Polymer Electrolyte Membrane or Proton Exchange Membrane (PEM)) of the membrane electrode assembly (Membrane Electrode Assembly (MEA)). If the polymer electrolyte membrane dries out, the power generation efficiency drops sharply.

[0005] Methods for humidifying a polymer electrolyte membrane include 1) a bubbler humidification method in which an internal pressure vessel is filled with water and the target gas is passed through a diffuser to supply moisture, 2) a direct injection method in which the amount of moisture required for the fuel cell reaction is calculated and moisture is supplied directly to the gas flow pipe via a solenoid valve, and 3) a humidification membrane method in which moisture is supplied to the gas flow layer using a polymer separation membrane. Among these, the membrane humidification method, which utilizes a membrane that selectively allows only water vapor contained in exhaust gas to pass through and provides water vapor to the air supplied to the polymer electrolyte membrane to humidify the polymer electrolyte membrane, is advantageous in that it allows the humidifier to be made lighter and smaller.

[0006] The selectively permeable membrane used in the membrane humidification method is preferably a hollow fiber membrane with a large permeation area per unit volume when forming a module. That is, when a membrane humidifier is manufactured using a hollow fiber membrane, it is possible to highly integrate hollow fiber membranes with a large contact surface area, and it is possible to sufficiently humidify a fuel cell even with a small capacity, and it is possible to use low-cost materials. It is also possible to recover moisture and heat contained in off-gas discharged at high temperatures from a fuel cell and reuse them through a humidifier. As shown in FIG. 1, a conventional membrane humidification type humidifier 1000 includes a humidification module 1100 in which moisture exchange occurs between air supplied from the outside and exhaust gas discharged from a fuel cell stack (not shown), and caps 1200 respectively connected to both ends of the humidification module 1100. One of the caps 12 transfers air supplied from the outside to the humidification module 1100, and the other transfers air humidified by the humidification module 1100 to the fuel cell stack.

[0007] The humidification module 1100 includes a mid-case 1110 having an off-gas inlet 1110a and an off-gas outlet 1110b, and a plurality of hollow fiber membranes 1120 in the mid-case 1110. Both ends of the bundle of hollow fiber membranes 1120 are potted on a fixing layer 1130. The fixing layer 1130 is generally formed by hardening a liquid polymer such as a liquid polyurethane resin by a casting method (e.g., dip casting or centrifugal casting). Air supplied from the outside flows along the hollow of hollow fiber membrane 1120. Exhaust gas that flows into mid-case 1110 through exhaust gas inlet 1110a comes into contact with the outer surface of hollow fiber membrane 1120 and is then discharged from mid-case 1110 through exhaust gas outlet 1110b. When the exhaust gas comes into contact with the outer surface of hollow fiber membrane 1120, moisture contained in the exhaust gas permeates hollow fiber membrane 1120, humidifying the air that was flowing along the hollow of hollow fiber membrane 1120.

[0008] The internal space of the cap 1200 must be fluidically connected only to the hollow of the hollow fiber membrane 1120 and completely isolated from the internal space of the mid-case 1110. Otherwise, gas leakage due to pressure difference will occur, reducing the power generation efficiency of the fuel cell. 1, together with the fixing layer 1130, the resin layer 1140 between the fixing layer 1130 and the mid-case 1110 isolates the interior space of the cap 1200 from the interior space of the mid-case 1110. Similar to the fixing layer 1130, the resin layer 1140 is generally formed by curing a liquid polymer, such as a liquid polyurethane resin, by a casting method (dip casting or centrifugal casting). However, (i) as the fuel cell is repeatedly operated and stopped, the resin layer 1140 expands and contracts alternately, and due to the difference in thermal expansion coefficient between the mid-case 1110 and the resin layer 1140, the resin layer 1140 is likely to separate from the mid-case 1110, causing a gap therebetween, or (ii) as a result of vibration and / or impact, a gap is likely to occur between the resin layer 1140 and the mid-case 1110. The gap between the resin layer 1140 and the mid-case 1110 causes gas leakage, reducing the power generation efficiency of the fuel cell.

[0009] In order to prevent gas leakage due to gaps occurring between the resin layer 1140 and the mid-case 1110, Korean Patent Registration No. 1697998 discloses a method of applying a sealant (liquid-phase sealant) to the steps on the side of the resin layer 1140 and the groove formed by the inner surface of the mid-case 1110, and then sandwiching a packing member (solid-phase sealant) in the groove and hardening the sealant. However, such a method has problems of low productivity and high manufacturing costs in that (i) the sealant must be applied precisely to fit the groove, which is inconvenient, (ii) it takes a fairly long time of 24 hours or more to harden the sealant, and (iii) a separate space is required to store the humidification module 1100 until the sealant hardens. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention aims to provide a fuel cell membrane humidifier that can prevent problems caused by the limitations and shortcomings of the related art as described above, reliably prevent gas leakage due to repeated operation and shutdown of a fuel cell, can be manufactured at relatively low manufacturing costs and with high productivity, and can suppress vibrations generated during operation. In addition to the above-mentioned aspects of the present invention, other features and advantages of the present invention will be described below or will be clearly understood by those having ordinary skill in the art from such description. [Means for solving the problem]

[0011] The fuel cell membrane humidifier according to an embodiment of the present invention comprises: The humidification module includes a humidification module that humidifies air supplied from the outside with moisture in exhaust gas discharged from a fuel cell stack, and caps that are respectively coupled to both ends of the humidification module. The humidification module includes a mid-case with both ends open and a step formed on an inner circumferential surface, at least one cartridge that is disposed in the mid-case and accommodates a plurality of hollow fiber membranes, a fixing layer on which the ends of the hollow fiber membranes are potted and supported by the inner wall of the mid-case, a bracket that is supported by the step of the mid-case and contacts the fixing layer, and a packing member that has a groove into which the end of the mid-case is sandwiched and contacts the bracket. The humidification module also includes a damping protrusion formed on the inner wall of the mid-case that is sandwiched between the fixing layer and suppresses vibrations generated in the cartridge due to air flowing inside the humidification module.

[0012] In the fuel cell membrane humidifier according to the embodiment of the present invention, the bracket and the packing member may each have a single closed curve shape corresponding to the cross-sectional shape of the mid-case. In the fuel cell membrane humidifier according to the embodiment of the present invention, the bracket may have a higher hardness than the packing member. In the fuel cell membrane humidifier according to the embodiment of the present invention, the bracket may have a hardness of 60 to 100 Shore A, and the packing member may have a hardness of 40 to 50 Shore A. In the fuel cell membrane humidifier according to an embodiment of the present invention, the packing member may include soft rubber, and the bracket may include metal, hard plastic, or hard rubber.

[0013] In the fuel cell membrane humidifier according to an embodiment of the present invention, the packing member may include silicone rubber or urethane rubber, and the bracket may include polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polycarbonate (PC), or acrylic resin. In the fuel cell membrane humidifier according to an embodiment of the present invention, the packing member may also be in contact with the fixing layer. In the fuel cell membrane humidifier according to an embodiment of the present invention, the fixing layer may include a first fixing layer to which an end of the hollow fiber membrane is potted, and a second fixing layer that covers the first fixing layer and contacts the bracket. In the fuel cell membrane humidifier according to the embodiment of the present invention, the first fixed layer and the second fixed layer may be made of the same material.

[0014] In the fuel cell membrane humidifier according to an embodiment of the present invention, the first fixing layer and the second fixing layer can both include polyurethane (PU) resin. In the fuel cell membrane humidifier according to an embodiment of the present invention, the humidification module may further include an inner case having both ends open within the mid-case, and the hollow fiber membrane may be disposed within the inner case. In the fuel cell membrane humidifier according to the embodiment of the present invention, an end of the inner case may be potted on the first fixing layer.

[0015] In addition, the fuel cell membrane humidifier according to the embodiment of the present invention includes: The humidification module includes a humidification module that humidifies air supplied from the outside with moisture in exhaust gas discharged from a fuel cell stack, and caps respectively attached to both ends of the humidification module. The humidification module includes a mid-case with both ends open and a step formed on its inner surface, at least one cartridge arranged in the mid-case and accommodating a plurality of hollow fiber membranes, a fixing layer to which the ends of the hollow fiber membranes are potted and supported by the inner wall of the mid-case, a bracket supported by the step of the mid-case and in contact with the fixing layer, and a packing member having a groove into which the end of the mid-case is sandwiched and in contact with the bracket. The inner wall of the mid-case is formed with a damping protrusion that is sandwiched between the fixing layer and suppresses vibrations generated in the cartridge due to air flowing inside the humidification module, and the hollow fiber membranes include a first group of hollow fiber membranes and a second group of hollow fiber membranes. The humidification module further includes a first inner case in which the hollow fiber membranes of the first group are arranged, and a second inner case in which the hollow fiber membranes of the second group are arranged, and the fixing layer includes a first fixing layer in which ends of the hollow fiber membranes of the first group are potted, a second fixing layer in which ends of the hollow fiber membranes of the second group are potted, and a third fixing layer that covers the first and second fixing layers and contacts the bracket.

[0016] In a fuel cell membrane humidifier according to an embodiment of the present invention, an end of the first inner case may be potted to the first fixing layer, and an end of the second inner case may be potted to the second fixing layer. Further details, such as implementations of various aspects of the present invention, are included in the following detailed description. Effect of the Invention

[0017] According to the present invention, the sealant application process and sealant curing process required in the conventional technology are omitted, which not only improves workability but also shortens manufacturing time, thereby dramatically improving productivity. Also, since no additional space is required to store the semi-finished products for the sealant curing process, the production cost of the humidifier may be reduced. Also, gas leakage caused by repeated operation and shutdown of the fuel cell can be prevented, and the fuel cell can be manufactured at relatively low manufacturing costs and with high productivity. In addition, a damping protrusion is formed between the mid-case and the fixing layer to suppress vibrations that occur during operation, to suppress air inside the mid-case from flowing to the cap, thereby enhancing the sealing function, and to facilitate the selection of the position of the fixing layer when forming the fixing layer. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is an exploded perspective view of a fuel cell membrane humidifier according to the prior art; [Diagram 2] 1 is a cross-sectional view showing a fuel cell membrane humidifier according to a first embodiment of the present invention. [Figure 3a] FIG. 1 is a perspective view of a bracket according to a first embodiment of the present invention. [Figure 3b] FIG. 3b is a cross-sectional view taken along line AA in FIG. 3a. [Figure 4a] FIG. 1 is a perspective view of a packing member according to a first embodiment of the present invention. [Figure 4b] FIG. 4b is a cross-sectional view taken along line AA in FIG. 4a. [Diagram 5] FIG. 4 is a cross-sectional view showing a fuel cell membrane humidifier according to a second embodiment of the present invention. [Figure 6a] 1A to 1C are cross-sectional views and the like for explaining a manufacturing method of a fuel cell membrane humidifier according to an embodiment of the present invention. [Figure 6b] 1A to 1C are cross-sectional views and the like for explaining a manufacturing method of a fuel cell membrane humidifier according to an embodiment of the present invention. [Figure 6c] 1A to 1C are cross-sectional views and the like for explaining a manufacturing method of a fuel cell membrane humidifier according to an embodiment of the present invention. [Figure 6d] 1A to 1C are cross-sectional views and the like for explaining a manufacturing method of a fuel cell membrane humidifier according to an embodiment of the present invention. [Figure 6e] 1A to 1C are cross-sectional views and the like for explaining a manufacturing method of a fuel cell membrane humidifier according to an embodiment of the present invention. [Figure 6f] 1A to 1C are cross-sectional views and the like for explaining a manufacturing method of a fuel cell membrane humidifier according to an embodiment of the present invention. [Figure 6g] 1A to 1C are cross-sectional views and the like for explaining a manufacturing method of a fuel cell membrane humidifier according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The present invention can be modified in various ways and can have various embodiments, and a specific embodiment will be illustrated and described in detail in the detailed description. However, this is not intended to limit the present invention to the specific embodiment, and it should be understood that the present invention includes all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention. The terms used in the present invention are merely used to describe certain embodiments and are not intended to limit the present invention. A singular expression includes a plural expression unless the context clearly indicates otherwise. In this specification, the terms "include" or "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. Hereinafter, a fuel cell membrane humidifier according to an embodiment of the present invention will be described with reference to the drawings.

[0020] The cross-sectional views of Figure 2 and Figures 5 to 6g are cross-sectional views of one end of the humidifier or semi-finished product, the other end having substantially the same (or symmetrical) cross-section. 2, the fuel cell membrane humidifier 2000 of the present invention includes a humidification module 2100 that humidifies air supplied from the outside with moisture in the exhaust gas discharged from the fuel cell stack. Each of the two ends of the humidification module 2100 is fastened to a cap 2200. One of the caps 2200 receives air from the outside through a port 2210 and transmits it to the humidification module 2100, and the other transmits air humidified by the humidification module 2100 to the fuel cell stack through the port 2210. The cap 2200 may be made of hard plastic (e.g., polycarbonate, polyamide (PA), polyphthalamide (PPA), etc.) or metal, and may have a simple closed curve shaped (e.g., circular or polygonal) traverse section.

[0021] The humidification module 2100 of one embodiment of the present invention is a device in which moisture exchange occurs between air supplied from the outside and exhaust gas supplied from a fuel cell stack, and comprises a mid-case 2110 with both ends open and having a step 2112 on its inner surface, a plurality of hollow fiber membranes 2121 in the mid-case 2110, a fixing layer 2122 to which the ends of the hollow fiber membranes 2121 are potted, a bracket 2130 supported by the steps 2112 of the mid-case 2110 and in contact with the fixing layer 2122, and a packing member 2140 having a groove into which the end of the mid-case 2110 is clamped and in contact with the bracket 2130. The mid-case 2110 has a port 2111 (only one is shown in FIG. 2) for exhaust gas inflow / outflow. The mid-case 2110 may be made of a hard plastic (e.g., polycarbonate, polyamide (PA), polyphthalamide (PPA), etc.) or metal, and may have a cross-section in the form of a single closed curve (e.g., circular or polygonal). According to one embodiment of the present invention, the mid-case 2110 may have a cross-section in the same form as the cap 2200.

[0022] The hollow fiber membrane 2121 may contain polysulfone resin, polyethersulfone resin, sulfonated polysulfone resin, polyvinylidene fluoride (PVDF) resin, polyacrylonitrile (PAN) resin, polyimide resin, polyamide-imide resin, polyester-imide resin, or a mixture of two or more of these. Air supplied from the outside through any one of the caps 2200 is humidified while flowing along the hollow of the hollow fiber membrane 2121, and then transmitted to the fuel cell stack through the other cap 2200. The exhaust gas that has flowed into mid-case 2110 comes into contact with the outer surface of hollow fiber membrane 2121, and is then discharged from mid-case 2110. When the exhaust gas comes into contact with the outer surface of hollow fiber membrane 2121, the moisture contained therein permeates hollow fiber membrane 2121, thereby humidifying the air flowing along the hollow of hollow fiber membrane 2121.

[0023] The fixing layer 2122 , which may be made of hard or soft polyurethane resin, must isolate the internal space of the cap 2200 from the internal space of the mid-case 2110 so that the cap 2200 is in fluid communication only with the hollow fiber membrane 2121 . However, as described above, (i) as the fuel cell is repeatedly operated and stopped, the fixing layer 2122 expands and contracts alternately, and due to the difference in thermal expansion coefficient between the mid-case 2110 and the fixing layer 2122, the fixing layer 2122 is likely to be separated from the mid-case 2110, causing a gap therebetween, or (ii) as a result of vibration and / or impact, a gap is likely to be caused between the fixing layer 2122 and the mid-case 2110. The gap between the fixing layer 2122 and the mid-case 2110 causes gas leakage, reducing the power generation efficiency of the fuel cell. Gas leakage that can be caused by the occurrence of a gap between the fixed layer 2122 and the mid-case 2110 includes (i) external leakage, in which exhaust gas in the internal space of the mid-case 2110 passes sequentially through the gap between the fixed layer 2122 and the mid-case 2110 and the gap between the cap 2200 and the mid-case 2110 to escape to the outside of the humidifier 2000, and (ii) internal leakage, in which exhaust gas in the internal space of the mid-case 2110 passes sequentially through the gap between the fixed layer 2122 and the mid-case 2110 and the gap between the fixed layer 2122 and the cap 2200 to enter the internal space of the cap 2200.

[0024] In order to prevent gas leakage due to the occurrence of a gap between the fixed layer 2122 and the mid-case 2110 , the fuel cell membrane humidifier 2000 of the present invention further includes a bracket 2130 , a packing member 2140 and a damping protrusion 2150 . As shown in FIGS. 3 a and 3 b , the bracket 2130 supported by the step 2112 of the mid-case 2110 may have a single closed curve shape corresponding to the cross-sectional shape of the mid-case 2110 . According to one embodiment of the present invention, the bracket 2130 has a higher hardness than the packing member 2140 and is strongly bonded to the fixing layer 2122 . For example, packing member 2140 may have a relatively low hardness of 30 to 60 Shore A, more preferably 40 to 50 Shore A, so that it may be compressed by the pressure applied when cap 2200 is tightened to mid-case 2110 by bolt 2310 and nut 2320, and bracket 2130 may have a hardness of 60 to 100 Shore A, more preferably 70 to 100 Shore A, which is higher than the hardness of packing member 2140.

[0025] As shown in FIGS. 4 a and 4 b , the packing member 2140 having a groove G into which the end of the mid-case 2110 is sandwiched may also have a single closed curve shape corresponding to the cross-sectional shape of the mid-case 2110 . According to one embodiment of the present invention, the packing member 2140 may include soft rubber (e.g., silicone rubber or urethane rubber), and the bracket 2130 may include metal, hard plastic [e.g., polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polycarbonate (PC), or acrylic resin], or hard rubber. When the cap 2200 is tightened to the mid-case 2110 by the bolts 2310 and nuts 2320, the portion of the packing member 2140 disposed between the cap 2200 and the mid-case 2110 (particularly, the portion of the packing member 2140 corresponding to the groove into which the end of the mid-case 2110 is pinched) is compressed by the pressure applied by the cap 2200 and the mid-case 2110, thereby preventing gas migration (i.e., external leakage) through the interface between the packing member 2140 and the mid-case 2110 and ensuring tight external sealing.

[0026] In addition, since the bracket 2130 is not only supported by the step 2112 of the mid-case 2110 but also has a relatively high hardness, when the cap 2200 is fastened to the mid-case 2110 by the bolt 2310 and the nut 2320, the bracket 2130 can effectively apply pressure to the packing member 2140 together with the cap 2200. As a result, the portion of the packing member 2140 disposed between the cap 2200 and the bracket 2130 [i.e., located inside the mid-case 2110] is sufficiently compressed, thereby preventing gas movement (i.e., internal leakage) through the interface between the packing member 2140 and the bracket 2130 and ensuring excellent internal sealing. In addition, the bracket 2130 according to an embodiment of the present invention has excellent adhesive strength with the fixing layer 2122, thereby preventing gas movement (i.e., internal leakage) through the interface between the bracket 2130 and the fixing layer 2122 and providing stronger internal sealing. If necessary, the surface of the bracket 2130 may be treated with a primer to further improve the adhesive strength between the bracket 2130 and the fixing layer 2122 and maximize the internal sealing effect.

[0027] The damping protrusion 2150 is formed to protrude from the inner wall of the mid-case 2110 toward the fixed layer 2122. The damping protrusion 2150 may be formed in a ring shape surrounding the inner wall of the mid-case 2110. During manufacture, the damping protrusion 2150 may be sandwiched in the fixed layer 2122 by a pressure method. The damping protrusion 2150 may be sandwiched in the second fixed layer 2122-2. Of course, the damping protrusion 2150 may also penetrate the second fixed layer 2122-2 and be sandwiched in the first fixed layer 2122-1. The damping protrusions 2150 are sandwiched between the fixed layer 2122 in a pressurized manner to compress the fixed layer 2122, thereby preventing air inside the mid-case 2110 from moving toward the cap 2200, thereby enabling tighter internal sealing. In addition, the damping protrusions 2150 are sandwiched between the fixing layer 2122 in a pressurized manner to compress the fixing layer 2122, thereby suppressing vibrations generated in the cartridge 2120 due to air flowing inside the humidification module 2100. That is, it is possible to suppress the cartridge 2120 from vibrating in the Z-axis direction due to the flow of dry air flowing in through the port 2210 of the cap (shown as the Z-axis direction in FIG. 2).

[0028] In addition, since the damping protrusions 2150 are formed to protrude from the inner wall of the mid-case 2110 toward the fixed layer 2122, it is possible to easily select the position of the fixed layer when forming the fixed layer during the manufacturing process. 2, the cap 2200 according to an embodiment of the present invention may have a cap protrusion 2220 at a position corresponding to the end of the mid-case 2110 that is sandwiched in the groove of the packing member 2140. The cap protrusion 2220 allows the packing member 2140 to be more effectively compressed together with the end of the mid-case 2110, thereby enabling a tighter external sealing. 2, the packing member 2140 according to an embodiment of the present invention may be in contact with the fixing layer 2122. By allowing the liquid resin (e.g., liquid polyurethane resin) used to form the fixing layer 2122 to be cured while in contact with the packing member 2140, the adhesive strength between the packing member 2140 and the fixing layer 2122 may be improved, and the internal sealing may be strengthened.

[0029] According to one embodiment of the present invention, as shown in FIG. 2, the fixing layer 2122 may include a first fixing layer 2122-1 to which the end of the hollow fiber membrane 2121 is potted, and a second fixing layer 2122-2 covering the first fixing layer 2122-1 and contacting the bracket 2130. The first fixing layer 2122-1 and the second fixing layer 2122-2 may be formed by hardening a liquid resin such as a liquid polyurethane resin by a dip casting method or a centrifugal casting method. The first fixing layer 2122-1 and the second fixing layer 2122-2 may be formed of different materials, but may be preferably formed of the same material (e.g., polyurethane resin) in terms of adhesive strength therebetween. 2, the humidification module 2100 may further include an inner case 2123 with both ends open in the mid-case 2110. In this case, the hollow fiber membrane 2121 is disposed in the inner case 2123. A first fixing layer 2122-1 to which the ends of the hollow fiber membrane 2121 are potted closes the open ends of the inner case 2123.

[0030] According to one embodiment of the present invention, the inner case 2123 has a plurality of holes H at positions corresponding to the ports 2111 (only one is shown in FIG. 2) for exhaust gas inflow / outflow. Exhaust gas that flows into the mid-case 2110 through the first port 2111 passes through the first hole H, and is dehydrated while flowing along the outer surface of the hollow fiber membrane 2121. Then, the exhaust gas exits the inner case 2133 through the second hole H on the opposite side, and is discharged from the mid-case 2110 through the second port 2111. The hollow fiber membrane 2121 , the first fixing layer 2122 - 1 , and the inner case 2123 constitute a hollow fiber membrane cartridge 2120 . As shown in FIG. 2, the end of the inner case 2123 is potted to the first fixing layer 2122-1, so that the relative positions of the hollow fiber membrane 2121 and the inner case 2123 can be kept constant.

[0031] A fuel cell membrane humidifier 2000 according to a second embodiment of the present invention will be described below with reference to FIG. As shown in FIG. 5, the fuel cell membrane humidifier 2000 according to the second embodiment of the present invention is substantially similar to the first embodiment described above, except that it includes two hollow fiber membrane cartridges 2120a, 2120b. That is, according to the second embodiment of the present invention, the hollow fiber membranes include a first group of hollow fiber membranes 2121a and a second group of hollow fiber membranes 2121b, the humidification module 2100 includes a first inner case 2123a in which the hollow fiber membranes 2121a of the first group are arranged and a second inner case 2123b in which the hollow fiber membranes 2121b of the second group are arranged, and the fixing layer 2122 includes a first fixing layer 2122-1a in which the ends of the hollow fiber membranes 2121a of the first group are potted, a second fixing layer 2122-1b in which the ends 2121b of the hollow fiber membranes of the second group are potted, and a third fixing layer 2122-2 that covers the first and second fixing layers 2122-1a, 2122-1b and contacts the bracket 2130.

[0032] The first group of hollow fiber membranes 2121a, the first fixing layer 2122-1a, and the first inner case 2123a constitute a first hollow fiber membrane cartridge 2120a, and the second group of hollow fiber membranes 2121b, the second fixing layer 2122-1b, and the second inner case 2123b constitute a second hollow fiber membrane cartridge 2120b. As shown in FIG. 5, the ends of the first and second inner cases 2123a, 2123b are potted into the first and second fixing layers 2122-1a, 2122-1b, respectively, so that the relative positions of the first group of hollow fiber membranes 2121a and the first inner case 2123a and the relative positions of the second group of hollow fiber membranes 2121b and the second inner case 2123b can each be maintained constant. For a larger humidification capacity, the number of hollow fiber membranes 2121 must be increased. However, in the case of the first embodiment having only one hollow fiber membrane cartridge 2120, the more hollow fiber membranes 2121 there are, the more difficult it becomes for exhaust gas to be transmitted to the hollow fiber membrane 2121 located in the center.

[0033] In contrast, in the second embodiment of the present invention, two hollow fiber membrane cartridges 2120a, 2120b are disposed spaced apart from each other, so that even if the number of the entire hollow fiber membranes 2121a, 2121b is increased, the exhaust gas can be transmitted relatively uniformly to the entire hollow fiber membranes 2121a, 2121b. In other words, when the number of hollow fiber membranes is the same, the structure of the second embodiment having two hollow fiber membrane cartridges 2120a, 2120b is advantageous in terms of hollow fiber membrane utilization compared to the structure of the first embodiment having only one hollow fiber membrane cartridge 2120. The number of hollow fiber membrane cartridges (and the like) to be mounted in the mid-case 2110 can be determined by taking into consideration the capacity of the fuel cell (or the required humidification capacity), the size of the humidifier, the weight of the humidifier, and the like. Hereinafter, the manufacturing method of the fuel cell membrane humidifier 2000 according to one embodiment of the present invention will be described in more detail with reference to FIGS. 6a to 6g.

[0034] First, as shown in FIG. 6a, a hollow fiber membrane cartridge 2120' is prepared in which the ends of a plurality of hollow fiber membranes 2121' are potted on a first fixing layer 2122-1'. The hollow fiber membrane cartridge 2120' may be manufactured by inserting at least a portion of each of the hollow fiber membranes 2121' into the inner case 2123, and then performing a dip casting process or a centrifugal casting process using a liquid resin such as a liquid polyurethane resin. The liquid resin is cured to form a first fixing layer 2122-1' to which the ends of the hollow fiber membranes 2121' are potted. When performing the dip casting process or the centrifugal casting process, the ends of the inner case 2123 may also be potted into the first fixing layer 2122-1' together with the ends of the hollow fiber membranes 2121'. The inner case 2123 may have first and second groups of holes H located on opposite sides along its length. Next, as shown in FIG. 6b, a hollow fiber membrane cartridge 2120' is inserted into a mid-case 2110 having both ends open and having a step 2112 and a damping protrusion 2150 formed on the inner circumferential surface.

[0035] According to an embodiment of the present invention, the mid-case 2110 has an open end and a cross section in the form of a single closed curve. The mid-case 2110 may have a partition wall dividing its internal space into an exhaust gas inlet space and an exhaust gas outlet space located on opposite sides along the length direction, and the hollow fiber membrane cartridge 2120' may be supported by the partition wall by being sandwiched in a hole formed in the partition wall. In this case, the first group of holes H of the inner case 2123 is present in the exhaust gas inlet space, and the second group of holes H of the inner case 2123 is present in the exhaust gas outlet space. In this case, the exhaust gas that enters the exhaust gas inlet space flows into the inner case 2123 through the first group of holes H, flows toward the second group of holes H within the inner case 2123, moves to the exhaust gas exhaust space through the second group of holes H, and is then exhausted from the mid-case 2110.

[0036] 6c, the bracket 2130 is attached onto the step 2112 of the mid-case 2110. As described above, the mid-case 2110 has a cross-section in the form of a single closed curve, and the bracket 2130 may have a single closed curve shape corresponding to the cross-sectional shape of the mid-case 2110. The bracket 2130 according to an embodiment of the present invention may be made of metal, hard plastic (e.g., polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polycarbonate (PC), or acrylic resin), or hard rubber. Optionally, the surface of the bracket 2130 may be treated with a primer before being mounted on the step 2112 of the mid-case 2110. 6d, a packing member 2140 having a groove corresponding to the end of the mid-case 2110 is then fitted onto the end of the mid-case 2110 such that the end of the mid-case 2110 is sandwiched in the groove and a portion of the packing member 2140 contacts the bracket 2130. The packing member 2140 may also have a single closed curve shape corresponding to the cross-sectional shape of the mid-case 2110.

[0037] Then, as shown in FIG. 6e, a second fixed layer 2122-2' is formed to fill the gap between the mid-case 2110, the bracket 2130, and the packing member 2140 and the end of the hollow fiber membrane cartridge 2120'. The second fixed layer 2122-2' can be manufactured by fastening a potting cap (not shown) to the mid-case 2110, injecting a liquid resin such as a liquid polyurethane resin into the potting cap while the potting cap is positioned below the mid-case 2110, performing a dip casting process to harden the resin, and then removing the potting cap. Alternatively, the second fixed layer 2122-2' can be formed by a centrifugal casting process.

[0038] The first and second fixing layers 2122-1', 2122-2' can each be composed of a different liquid resin, but in terms of adhesive strength between them, it may be preferable for them to be each formed of the same material (e.g., liquid polyurethane resin). According to one embodiment of the present invention, the liquid resin (e.g., liquid polyurethane) used to form the second fixing layer 2122-2' is hardened while in contact with the bracket 2130 and the packing member 2140, thereby improving the adhesion of the second fixing layer 2122-2' to them and strengthening the internal sealing. According to one embodiment of the present invention, the bracket 2130 is formed of a material having excellent adhesive strength with the second fixing layer 2122-2', so that gas migration (i.e., internal leakage) through the interface therebetween can be prevented and stronger internal sealing can be provided. Also, as described above, when the bracket 2130 is surface-treated with a primer, the adhesive strength between the bracket 2130 and the second fixing layer 2122-2' is maximized, so that better internal sealing can be provided. Next, 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 in Figure 6e to obtain a hollow fiber membrane 2121 with an open end potted on the first fixing layer 2122-1 surrounded by the second fixing layer 2122-2, as shown in Figure 6f.

[0039] Then, as shown in FIG. 6g, the cap 2200 is tightened onto the mid-case 2110, but in such a way that the cap 2200 compresses the packing member 2140. 6g, the cap 2200 according to an embodiment of the present invention may have a cap protrusion 2220 at a position corresponding to the end of the mid-case 2110 that is sandwiched in the groove of the packing member 2140. The cap protrusion 2220 may more effectively compress the packing member 2140 together with the end of the mid-case 2110, thereby enabling a tighter external sealing. Also, according to one embodiment of the present invention, the bracket 2130 has a higher hardness than the packing member 2140, so that the packing member 2140 can be compressed when the cap 2200 is tightened onto the mid-case 2110. That is, since the bracket 2130 is not only supported by the step 2112 of the mid-case 2110, but also has a higher hardness (60 to 100 Shore A, more preferably 70 to 100 Shore A) than the hardness of the packing member 2140 (30 to 60 Shore A, more preferably 40 to 50 Shore A), when the cap 2200 is fastened to the mid-case 2110 by the bolt 2310 and the nut 2320, the bracket 2130 can effectively apply pressure to the packing member 2140 together with the cap 2200. As a result, the portion of the packing member 2140 disposed between the cap 2200 and the bracket 2130 [i.e., located inside the mid-case 2110] is sufficiently compressed, thereby preventing gas movement (i.e., internal leakage) through the interface between the packing member 2140 and the bracket 2130, and ensuring excellent internal sealing.

[0040] According to the present invention described above, both external and internal leakage can be effectively prevented only through mechanical assembly of the bracket 2130 and the packing member 2140 without the sealant application and hardening processes of the conventional technology. Therefore, according to the present invention, the sealant application and hardening processes required in the conventional technology are omitted, so that not only the workability is improved, but also the manufacturing time is shortened, and the productivity can be improved dramatically. In addition, since a separate space for storing the semi-finished product during the sealant hardening process is not required, the production cost of the humidifier can be reduced. In addition, the damping protrusion 2150 is formed between the mid-case 2110 and the fixing layer 2122, so that vibrations generated during operation can be suppressed, the air inside the mid-case can be suppressed from flowing to the cap, the sealing function can be strengthened, and the position of the fixing layer can be easily selected when forming the fixing layer.

[0041] Although one embodiment of the present invention has been described above, a person having ordinary knowledge in the art would be able to modify and change the present invention in various ways by adding, changing, deleting, or adding components without departing from the concept of the present invention described in the claims, and this would also be considered to be within the scope of the claims of the present invention. [Explanation of symbols]

[0042] 2000:Fuel cell membrane humidifier 2100: Humidification module 2110: Mid-case 2120: Hollow fiber membrane cartridge 2121: Hollow fiber membrane 2122: Fixed layer 2130: Bracket 2140: Packing material 2150: Damping protrusion

Claims

1. a humidification module that humidifies air supplied from the outside with moisture contained in exhaust gas discharged from the fuel cell stack; a cap coupled to each end of the humidification module; Equipped with The humidification module includes: A mid-case having open ends and a step formed on an inner circumferential surface; At least one cartridge disposed within the mid-case and housing a plurality of hollow fiber membranes; An anchoring layer to which the ends of the hollow fiber membranes are potted and supported by the inner wall of the mid-case; a bracket supported by a step of the mid-case and in contact with the fixed layer; a packing member having a groove into which an end of the mid-case is sandwiched and which contacts the bracket; Equipped with a damping protrusion is formed on an inner wall of the mid-case, the damping protrusion being sandwiched between the fixing layers and configured to suppress vibrations generated in the cartridge by air flowing inside the humidification module; The damping protrusion is formed to protrude from an inner wall of the midcase toward the fixing layer.

2. The bracket and the packing member are 2. The fuel cell membrane humidifier of claim 1, each having a single closed curve shape corresponding to a cross-sectional shape of the mid-case.

3. The bracket is 2. The fuel cell membrane humidifier of claim 1, having a higher hardness than the packing member.

4. 4. The fuel cell membrane humidifier according to claim 3, wherein the bracket has a hardness of 60 to 100 Shore A, and the packing member has a hardness of 40 to 50 Shore A.

5. The packing member includes a soft rubber, The fuel cell membrane humidifier of claim 1 , wherein the bracket comprises metal, hard plastic, or hard rubber.

6. The packing member includes silicone rubber or urethane rubber, 6. The fuel cell membrane humidifier of claim 5, wherein the bracket comprises polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polycarbonate (PC), or acrylic resin.

7. The packing member is The fuel cell membrane humidifier of claim 1 also in contact with said fixed bed.

8. The fixing layer is a first fixing layer in which an end of the hollow fiber membrane is potted; a second fastening layer covering the first fastening layer and in contact with the bracket; 2. The fuel cell membrane humidifier of claim 1, comprising:

9. 9. The fuel cell membrane humidifier of claim 8, wherein the first and second immobile layers are formed of the same material.

10. 9. The fuel cell membrane humidifier of claim 8, wherein the first and second fixing layers both comprise polyurethane (PU) resin.

11. The humidification module further includes an inner case having both ends open and disposed within the mid-case. The fuel cell membrane humidifier according to claim 8 , wherein the hollow fiber membrane is disposed within the inner case.

12. The fuel cell membrane humidifier according to claim 11 , wherein an end of the inner case is potted to the first fixing layer.

13. a humidification module that humidifies air supplied from the outside with moisture contained in exhaust gas discharged from the fuel cell stack; a cap coupled to each end of the humidification module; Equipped with The humidification module includes: A mid-case having open ends and a step formed on an inner circumferential surface; At least one cartridge disposed within the mid-case and housing a plurality of hollow fiber membranes; An anchoring layer to which the ends of the hollow fiber membranes are potted and supported by the inner wall of the mid-case; a bracket supported by a step of the mid-case and in contact with the fixed layer; a packing member having a groove into which an end of the mid-case is sandwiched and which contacts the bracket; Equipped with a damping protrusion is formed on an inner wall of the mid-case, the damping protrusion being sandwiched between the fixing layers and suppressing vibrations generated in the cartridge by air flowing inside the humidification module; The hollow fiber membranes include a first group of hollow fiber membranes and a second group of hollow fiber membranes, The humidification module includes: a first inner case in which the first group of hollow fiber membranes is disposed; a second inner case in which the second group of hollow fiber membranes is disposed; and Further equipped with The fixing layer is a first fixing layer in which the ends of the hollow fiber membranes of the first group are potted; a second fixing layer in which the ends of the hollow fiber membranes of the second group are potted; a third fastening layer covering the first and second fastening layers and in contact with the bracket; Equipped with The damping protrusion is formed to protrude from an inner wall of the midcase toward the fixing layer.

14. an end of the first inner case is potted on the first fixing layer; 14. The fuel cell membrane humidifier of claim 13, wherein an end of the second inner case is potted to the second fixing layer.

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