Humidifier for fuel cell

Abstract

The present invention relates to a humidifier for a fuel cell, the humidifier comprising: a humidification module; a first cap coupled to one end of the humidification module; and a second cap coupled to the other end of the humidification module, wherein the humidification module includes a mid-case, at least one cartridge, and a partition part dividing the interior of the mid-case into an inflow space and an outflow space, the cartridge includes an inner case, a compartment part, and a plurality of hollow fiber membrane bundles received in each of multiple sub-cartridges, and the compartment part includes differential pressure reduction holes in communication with the inflow space and the outflow space.

Description

Humidifier for fuel cell

[0001] The present invention relates to a humidifier for a fuel cell for supplying humidified gas to a fuel cell.

[0002] Unlike conventional chemical cells such as batteries or accumulators, fuel cells can continuously produce electricity as long as hydrogen and oxygen are supplied, and they have the advantage of being about twice as efficient as internal combustion engines because there is no heat loss.

[0003] Furthermore, because they directly convert the chemical energy generated by the combination of hydrogen and oxygen into electrical energy, they produce fewer pollutants. Therefore, fuel cells are not only environmentally friendly but also offer the advantage of reducing concerns about resource depletion due to increasing energy consumption.

[0004] Depending on the type of electrolyte used, these fuel cells can be broadly classified into polymer electrolyte membrane fuel cells (PEMFC), phosphoric acid fuel cells (PAFC), molten carbonate fuel cells (MCFC), solid oxide fuel cells (SOFC), and alkaline fuel cells (AFC).

[0005] While each of these fuel cells operates on fundamentally identical principles, they differ in the type of fuel used, operating temperature, catalyst, and electrolyte. Among these, polymer electrolyte membrane fuel cells (PEMFCs) are known to be the most promising, not only for small-scale stationary power generation but also for transportation systems, due to their low-temperature operation and high power density, which allows for miniaturization.

[0006] One of the most important factors in improving the performance of polymer electrolyte membrane fuel cells (PEMFCs) is maintaining the moisture content of the polymer electrolyte membrane (or proton exchange membrane: PEM) of the membrane electrode assembly (MEA) by supplying a certain amount of moisture. This is because power generation efficiency rapidly declines when the polymer electrolyte membrane dries.

[0007] Methods for humidifying a polymer electrolyte membrane include 1) a bubbler humidification method in which a 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 a fuel cell reaction is calculated and moisture is directly supplied to the gas flow pipe through a solenoid valve; and 3) a humidification membrane method in which moisture is supplied to a gas fluidized bed using a polymer membrane.

[0008] Among these, the membrane humidification method, which humidifies the polymer electrolyte membrane by providing water vapor to the air supplied to the polymer electrolyte membrane using a membrane that selectively transmits only water vapor contained in the exhaust gas, is advantageous in that it can make the humidifier lightweight and compact.

[0009] The selectively permeable membrane used in membrane humidification is preferably a hollow fiber membrane with a large permeable area per unit volume when forming a module. This allows for high integration of hollow fiber membranes with a large contact surface area in humidifiers, enabling sufficient humidification of fuel cells even with small capacities. Furthermore, it allows for the use of inexpensive materials. Furthermore, the moisture and heat contained in the high-temperature off-gas emitted from the fuel cell can be recovered and reused in the humidifier.

[0010] Figure 1 is a schematic exploded perspective view of a typical fuel cell humidifier.

[0011] As illustrated in Fig. 1, a conventional membrane humidifier (100) includes a humidifying module (110) in which moisture exchange occurs between air supplied from the outside and exhaust gas discharged from a fuel cell stack (not shown), and caps (120) connected to both ends of the humidifying module (110).

[0012] One of the above caps (120) delivers air supplied from the outside to the humidifying module (110), and the other delivers air humidified by the humidifying module (110) to the fuel cell stack.

[0013] The humidifying module (110) includes a mid-case (111) having an off-gas inlet (111a) and an off-gas outlet (111b), and a plurality of hollow fiber membranes (112) within the mid-case (111). Both ends of the hollow fiber membranes (112) are potted in a potting layer (113). The potting layer (113) is generally formed by curing a liquid polymer such as a liquid polyurethane resin through a casting method. The potting layer (113) in which the ends of the hollow fiber membranes (112) are potted and the resin layer (114) between the potting layer (113) and the mid-case (111) block the internal spaces of the caps (120) from the internal space of the mid-case (111). Similar to the potting layer (113) above, the resin layer (114) is generally formed by curing a liquid polymer such as a liquid polyurethane resin through a casting method.

[0014] Air supplied from the outside flows along the hollow fiber membranes (112). The exhaust gas introduced into the mid-case (111) through the exhaust gas wet gas inlet (111a) comes into contact with the outer surface of the hollow fiber membranes (112) and then flows out from the mid-case (111) through the exhaust gas wet gas outlet (111b). When the exhaust gas comes into contact with the outer surface of the hollow fiber membranes (112), moisture contained in the exhaust gas permeates the hollow fiber membranes (112), thereby humidifying the air flowing along the hollow fiber membranes (112).

[0015] In this case, the shell pressure difference due to the exhaust gas flowing along the outer side of the hollow fiber membranes (112) may increase excessively, which increases the amount of electricity generated in the fuel cell system used on the compressor side. Accordingly, there is a problem of reducing the overall efficiency of the fuel cell system in the past.

[0016] The present invention has been devised to solve the above-described problem, and to provide a humidifier for a fuel cell capable of preventing excessive increase in shell pressure.

[0017] To solve the above-mentioned problem, the present invention may include the following configuration.

[0018] A humidifier for a fuel cell according to the present invention may include a humidifying module; a first cap coupled to one end of the humidifying module; and a second cap coupled to the other end of the humidifying module. The humidifying module may include a mid-case having open ends, at least one cartridge accommodated inside the mid-case, and a partition wall portion dividing the interior of the mid-case into an inlet space into which a first gas flows in and an outlet space through which the first gas flows out. The cartridge may include an inner case having openings at both ends; a partition portion dividing the interior of the inner case into a plurality of sub-cartridges; and a plurality of hollow fiber membrane bundles accommodated in each of the sub-cartridges. The partition portion may include a differential pressure reducing hole communicating with each of the inlet space and the outlet space.

[0019] The above humidifying module can humidify dry gas to be supplied to the fuel cell stack using wet gas.

[0020] The present invention utilizes a pressure reduction hole to prevent excessive increases in the shell pressure differential between the inlet and outlet spaces separated by a partition wall. Accordingly, the present invention can reduce the amount of electricity generated in the fuel cell system used by the compressor side for the flow of the first gas, thereby contributing to improving the overall efficiency of the fuel cell system.

[0021] The present invention can divide a cartridge into sub-cartridges using a partition, thereby reducing the internal cross-sectional area of ​​each sub-cartridge and also reducing the size of the hollow fiber membrane bundles accommodated in the sub-cartridges. Accordingly, the present invention can increase the number of hollow fiber membranes in each of the hollow fiber membrane bundles that come into contact with a first gas and participate in humidification. Accordingly, the present invention can improve the overall humidification efficiency by improving the humidification efficiency of each sub-cartridge.

[0022] Figure 1 is a schematic exploded perspective view of a typical fuel cell humidifier.

[0023] Figure 2 is a schematic exploded perspective view of a fuel cell humidifier according to the present invention.

[0024] Figure 3 is a schematic exploded cross-sectional view showing a fuel cell humidifier according to the present invention along line II of Figure 2.

[0025] Figure 4 is a schematic cross-sectional view showing a fuel cell humidifier according to the present invention along line II of Figure 2.

[0026] Figures 5 and 6 are schematic plan views of a cartridge in a fuel cell humidifier according to the present invention.

[0027] Figure 7 is a schematic cross-sectional view showing a cartridge of a fuel cell humidifier according to the present invention taken along line II-II of Figure 6.

[0028] Figure 8 is a schematic side cross-sectional view showing a cartridge of a fuel cell humidifier according to the present invention along line Ⅲ-Ⅲ of Figure 7.

[0029] Figure 9 is a schematic cross-sectional view showing a cartridge of a fuel cell humidifier according to the present invention along line IV-IV of Figure 6.

[0030] Figure 10 is a schematic cross-sectional view showing a cartridge of a fuel cell humidifier according to the present invention along the line V-V of Figure 7.

[0031] FIG. 11 is a schematic cross-sectional view showing an embodiment of a cartridge of a fuel cell humidifier according to the present invention including a plurality of compartments, taken along line II-II of FIG. 6.

[0032] Hereinafter, embodiments of a fuel cell humidifier according to the present invention will be described in detail with reference to the attached drawings. In FIGS. 9 and 10, two parallel dashed lines are omitted. In FIGS. 7, 9, and 11, a bundle of hollow fiber membranes is schematically depicted using dot hatching.

[0033] Referring to FIGS. 2 to 4, a fuel cell humidifier (1) according to the present invention uses wet gas to humidify dry gas to be supplied to a fuel cell stack (not shown). The wet gas may be discharged from the fuel cell stack. The dry gas may be fuel gas or air. The dry gas may be supplied to the fuel cell stack after being humidified by the wet gas. The fuel cell humidifier (1) according to the present invention includes a humidifying module (2), a first cap (3) coupled to one end of the humidifying module (2), and a second cap (4) coupled to the other end of the humidifying module (2). The humidifying module (2) can humidify dry gas. The humidifying module (2) can humidify dry gas to be supplied to the fuel cell stack using the wet gas.

[0034] Referring to FIGS. 2 to 4, the humidifying module (2) humidifies dry gas. The first cap (3) may be coupled to one end of the humidifying module (2). The second cap (4) may be coupled to the other end of the humidifying module (2). The humidifying module (2) may supply humidified dry gas to the fuel cell stack using a first gas and a second gas. When the first gas is a dry gas, the second gas may be a wet gas. In this case, the first gas may be supplied to the fuel cell stack after being humidified by the second gas. When the first gas is a wet gas, the second gas may be a dry gas. In this case, the second gas may be supplied to the fuel cell stack after being humidified by the first gas.

[0035] The above humidifying module (2) includes a mid-case (21) and at least one cartridge (22).

[0036] The above mid-case (21) is combined with the cartridge (22). The cartridge (22) can be accommodated inside the mid-case (21). The mid-case (21) has both ends open. In this case, a receiving hole (211) can be formed in the mid-case (21). The receiving hole (211) can be formed to penetrate the mid-case (21) in the first axial direction (X-axis direction). At least one cartridge (22) can be arranged in the receiving hole (211).

[0037] The above-mentioned mid-case (21) may include a mid-body (210). The mid-body (210) accommodates the cartridge (22). The cartridge (22) is arranged inside the mid-body (210) so that it can be accommodated in the mid-body (210). At least one cartridge (22) can be accommodated in the mid-body (210). The accommodation hole (211) may be formed to penetrate the mid-body (210) in the first axial direction (X-axis direction).

[0038] The above-mentioned mid-case (21) may include a mid inlet (212) and a mid outlet (213). The mid inlet (212) may introduce the first gas into the interior of the mid body (210). The mid outlet (213) may discharge the first gas from the interior of the mid body (210). The mid outlet (213) and the mid inlet (212) may each protrude from the mid body (210). The mid outlet (213) and the mid inlet (212) may be spaced apart from each other along the first axial direction (X-axis direction). The mid outlet (213), the mid inlet (212), and the mid body (210) may be formed integrally.

[0039] The cartridge (22) is arranged inside the mid-case (21). The cartridge (22) can be accommodated in the mid-body (210). The cartridge (22) includes a hollow fiber membrane bundle (221). The hollow fiber membrane bundle (221) can be modularized by being coupled to the cartridge (22). Accordingly, through a process of coupling the cartridge (22) to the mid-case (21), the hollow fiber membrane bundle (221) can be installed inside the mid-case (21). Therefore, the fuel cell humidifier (1) according to the present invention can improve the ease of installation, separation, and replacement of the hollow fiber membrane bundle (221). The hollow fiber membrane bundle (221) can include a plurality of hollow fiber membranes. Each of the hollow fiber membranes can include a hollow space through which the second gas passes.

[0040] The above cartridge (22) may include an inner case (222).

[0041] The inner case (222) has openings at both ends and contains the hollow fiber membrane bundle (221). The hollow fiber membrane bundle (221) can be modularized by being placed inside the inner case (222). The hollow fiber membrane bundle (221) can 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.

[0042] The cartridge (22) may include a first fixing layer (223). The first fixing layer (223) fixes one end of the hollow fiber membrane bundle (221). The first fixing layer (223) may close an opening formed in one end of the inner case (222). In this case, the first fixing layer (223) may be formed so as not to block the hollow fiber membranes of the hollow fiber membrane bundle (221). The first fixing layer (223) may be formed by curing a liquid resin, such as a liquid polyurethane resin, through a casting process. A portion of the first fixing layer (223) may be positioned inside the inner case (222), and the remaining portion may protrude outside the inner case (222). The above first fixed layer (223) can also fix one end of the hollow fiber membrane bundle (221) and the inner case (222).

[0043] The cartridge (22) may include a second fixed layer (224). The second fixed layer (224) fixes the other end of the hollow fiber membrane bundle (221). The second fixed layer (224) may close an opening formed at the other end of the inner case (222). In this case, the second fixed layer (224) may be formed so as not to block the hollow fiber membranes of the hollow fiber membrane bundle (221). The second fixed layer (224) may be formed by curing a liquid resin, such as a liquid polyurethane resin, through a casting process. A portion of the second fixed layer (224) may be positioned inside the inner case (222), and the remaining portion may protrude outside the inner case (222). The second fixed layer (224) may also fix the other end of the hollow fiber membrane bundle (221) and the inner case (222). Since the second fixed layer (224) and the first fixed layer (223) are formed so as not to block the hollow fiber membranes of the hollow fiber membrane bundle (221), the second gas can be supplied to the hollow fiber membranes of the hollow fiber membrane bundle (221) without being obstructed by the second fixed layer (224) and the first fixed layer (223), and can flow out from the hollow fiber membranes of the hollow fiber membrane bundle (221) without being obstructed by the second fixed layer (224) and the first fixed layer (223).

[0044] Referring to FIGS. 2 to 6, the cartridge (22) may include an inner inlet (225) and an inner outlet (226).

[0045] The inner inlet (225) is formed in the inner case (222). The inner inlet (225) may be formed in at least one side surface among side surfaces of the inner case (222). The side surfaces of the inner case (222) may be surfaces arranged to surround an inner hole formed to penetrate the inner case (222) so as to form openings at both ends of the inner case (222). The inner hole may be formed to extend along the first axial direction (X-axis direction) and penetrate the inner case (222). The inner inlet (225) may be arranged to face at least one side wall among side walls of the mid-case (21). The inner inlet (225) may introduce the first gas into the interior of the inner case (222). The inner inlet (225) may be formed by penetrating the inner case (222). As illustrated in FIG. 5, the inner inlet (225) may be implemented as a single through hole penetrating the inner case (222). As illustrated in FIG. 6, the inner inlet (225) may also be implemented as a plurality of through holes penetrating the inner case (222). In this case, the inner inlet (225) may include a plurality of inlet windows (225a) formed to penetrate different portions of the inner case (222). The inlet windows (225a) may be arranged to be spaced apart from each other along the first axial direction (X-axis direction) and the second axial direction (Y-axis direction) to form a matrix. The second axial direction (Y-axis direction) and the first axial direction (X-axis direction) are axial directions that are arranged perpendicular to each other.

[0046] The inner outlet (226) is formed in the inner case (222). The inner outlet (226) may be formed in at least one side surface among the side surfaces of the inner case (222). The inner outlet (226) may discharge the first gas from the inside of the inner case (222). The inner outlet (226) may be formed by penetrating the inner case (222). As illustrated in FIG. 5, the inner outlet (226) may be implemented as a single through hole penetrating the inner case (222). As illustrated in FIG. 6, the inner outlet (226) may also be implemented as a plurality of through holes penetrating the inner case (222). In this case, the inner outlet (226) may include a plurality of outlet windows (226a) formed to penetrate different parts of the inner case (222). The outlet windows (226a) may be arranged to form a matrix shape by being spaced apart from each other along the first axial direction (X-axis direction) and the second axial direction (Y-axis direction). The inner outlet (226) and the inner inlet (225) may be arranged at positions spaced apart from each other along the first axial direction (X-axis direction).

[0047] When the first gas is a wet gas, the first gas is supplied between the inner surface of the mid-case (21) and the outer surface of the cartridge (22) through the mid inlet (212), and is supplied into the interior of the cartridge (22) through the inner inlet (225) so as to contact the outer surface of the hollow fiber membrane bundle (221). In this process, moisture contained in the first gas can permeate the hollow fiber membranes of the hollow fiber membrane bundle (221), thereby humidifying the second gas flowing along the cavities of the hollow fiber membranes of the hollow fiber membrane bundle (221). The humidified second gas can be supplied to the fuel cell stack through the first cap (3) or the second cap (4) after flowing out from the hollow fiber membrane bundle (221). The first gas after humidifying the second gas may flow out between the outer surface of the cartridge (22) and the inner surface of the mid-case (21) through the inner outlet (226), and may flow out to the outside of the mid-case (21) through the mid outlet (213). In this case, the first gas may be an off-gas discharged from the fuel cell stack.

[0048] When the first gas is a dry gas, the first gas is supplied between the inner surface of the mid-case (21) and the outer surface of the cartridge (22) through the mid inlet (212), and is supplied into the interior of the cartridge (22) through the inner inlet (225) so as to contact the outer surface of the hollow fiber membrane bundle (221). In this process, the moisture of the second gas flowing along the hollow fiber membranes of the hollow fiber membrane bundle (221) can humidify the first gas introduced into the interior of the cartridge (22) by permeating the hollow fiber membranes of the hollow fiber membrane bundle (221). The humidified first gas may flow out between the outer surface of the cartridge (22) and the inner surface of the mid-case (21) through the inner outlet (226), and may be supplied to the fuel cell stack after flowing out to the outside of the mid-case (21) through the mid outlet (213). The second gas after humidifying the first gas may flow out from the hollow fiber membrane bundle (221) and then be discharged to the outside through the first cap (3) or the second cap (4). In this case, the second gas may be an off-gas discharged from the fuel cell stack.

[0049] The above humidifying module (2) may include a first packing portion (23).

[0050] The first packing part (23) is air-tightly coupled to one end of the mid-case (21) through mechanical assembly. Accordingly, the first packing part (23) can allow the first cap (3) to be in fluid communication only with the hollow fiber membrane bundle (221). Therefore, the first packing part (23) can prevent the first gas and the second gas from being directly mixed. The first packing part (23) is arranged between the mid-case (21) and the cartridge (22), thereby sealing the space between the mid-case (21) and the cartridge (22). In this case, the cartridge (22) can be inserted into the first insertion hole (231) formed in the first packing part (23). The first packing portion (23) may be in contact with each of the inner surface of the mid-case (21), the outer surface of the cartridge (22), and the first fixing layer (223). Through this contact, the first packing portion (23) may be hermetically coupled to one end of the mid-case (21). In this case, the first packing portion (23) may be in contact with each of a portion of the inner surface of the mid-case (21), a portion of the outer surface of the cartridge (22), and a portion of the first fixing layer (223).

[0051] The above humidifying module (2) may include a second packing part (24).

[0052] The second packing part (24) is airtightly coupled to the other end of the mid-case (21) through mechanical assembly. Accordingly, the second packing part (24) can allow the second cap (4) to be in fluid communication only with the hollow fiber membrane bundle (221). Therefore, the second packing part (24) can prevent the first gas and the second gas from being directly mixed. The second packing part (24) is arranged between the mid-case (21) and the cartridge (22), thereby sealing the space between the mid-case (21) and the cartridge (22). In this case, the cartridge (22) can be inserted into the second insertion hole (241) formed in the second packing part (24). The second packing portion (24) may be in contact with each of the inner surface of the mid-case (21), the outer surface of the cartridge (22), and the second fixing layer (224). Through this contact, the second packing portion (24) may be hermetically coupled to the other end of the mid-case (21). In this case, the second packing portion (24) may be in contact with each of a portion of the inner surface of the mid-case (21), a portion of the outer surface of the cartridge (22), and a portion of the second fixing layer (224).

[0053] The above humidifying module (2) may include a partition wall (25).

[0054] The above-mentioned partition wall (25) divides the interior of the mid-case (21) into an inlet space (IS) into which the first gas flows in and an outlet space (OS) from which the first gas flows out. The partition wall (25) can block the first gas flowing in through the mid inlet (212) from flowing directly into the outlet space (OS) without passing through the interior of the cartridge (22). Accordingly, the first gas flowing in through the mid inlet (212) can flow into the outlet space (OS) only through the interior of the cartridge (22). The cartridge (22) can be inserted into the partition wall (25) such that the inner inlet (225) is arranged in the inlet space (IS) and the inner outlet (226) is arranged in the outlet space (OS). The above-mentioned partition wall portion (25) can be joined to the mid-case (21) so as to protrude from the inner surface of the mid-case (21). The partition wall portion (25) can be closely attached to the outer surface of the cartridge (22), thereby partitioning the inlet space (IS) and the outlet space (OS) so as not to be in fluid communication with each other. The partition wall portion (25) and the mid-case (21) may also be formed integrally.

[0055] Referring to FIGS. 2 to 4, the first cap (3) is coupled to one end of the humidifying module (2). The space between the first cap (3) and the cartridge (22) can be sealed against the space between the cartridge (22) and the mid-case (21) by the first packing portion (23). The first cap (3) can include a first port (31). The first port (31) is for the second gas to flow. The first port (31) can communicate with the hollow fiber membranes of the hollow fiber membrane bundle (221). Accordingly, in the process of the second gas flowing between the first cap (3) and the hollow fiber membrane bundle (221), the second gas can be introduced or discharged through the first port (31).

[0056] Referring to FIGS. 2 to 4, the second cap (4) is coupled to the other end of the humidifying module (2). The second cap (4) may be positioned at a position spaced apart from the first cap (3) along the first axial direction (X-axis direction). The space between the second cap (4) and the cartridge (22) may be sealed against the space between the cartridge (22) and the mid-case (21) by the second packing portion (24). The second cap (4) may include a second port (41). The second port (41) is for the second gas to flow. The second port (41) may be communicated with the hollow fiber membranes of the hollow fiber membrane bundle (221). Accordingly, in the process in which the second gas flows between the second cap (4) and the hollow fiber membrane bundle (221), the second gas can be introduced or introduced through the second port (41). When the second gas is introduced through the second port (41), the second gas can be introduced through the first port (31). In this case, the second gas can exchange moisture with the first gas while sequentially passing through the second cap (4), the hollow fiber membranes of the hollow fiber membrane bundle (221), and the first cap (3). When the second gas is introduced through the second port (41), the second gas can be introduced through the first port (31). In this case, the second gas can exchange moisture with the first gas while sequentially passing through the first cap (3), the hollow fiber membranes of the hollow fiber membrane bundle (221), and the second cap (4). Although not shown, resin layers may be formed on both ends of the mid-case (21) instead of the packing parts (5, 6). The resin layers can be formed by curing a liquid polymer, such as a liquid polyurethane resin, through a casting method.

[0057] Here, in the process in which the first gas introduced into the inflow space (IS) flows through the interior of the cartridge (22) to the outlet space (OS), the shell pressure difference between the inflow space (IS) and the outlet space (OS) may excessively increase due to the densely packed hollow fiber membrane bundles (221) inside the cartridge (22). This may increase the amount of electricity generated in the fuel cell system used by the compressor side for the flow of the first gas, thereby lowering the overall efficiency of the fuel cell system. To prevent this, the cartridge (22) may include a partition (227, illustrated in FIG. 7).

[0058] Referring to FIGS. 7 to 11, the partition (227) can partition the interior of the inner case (222) into a plurality of sub-cartridges (22a, 22b). In this case, the cartridge (22) can include a plurality of hollow fiber membrane bundles (221a, 221b) accommodated in each of the sub-cartridges (22a, 22b). Each of the sub-cartridges (22a, 22b) can be implemented with a portion of the inner case (222) and the hollow fiber membrane bundle (221a). Moisture exchange between the first gas and the second gas can occur inside each of the sub-cartridges (22a, 22b).

[0059] The plurality of sub-cartridges (22a, 22b) include a first sub-cartridge (22a) and a second sub-cartridge (22b). The plurality of sub-cartridges (22a, 22b) are also referred to as "sub-cartridges (22a, 22b)". The plurality of hollow fiber membrane bundles (221a, 221b) include a first hollow fiber membrane bundle (221a) and a second hollow fiber membrane bundle (221b). The plurality of hollow fiber membrane bundles (221a, 221b) are also referred to as "hollow fiber membrane bundles (221a, 221b)".

[0060] The above-mentioned partition (227) may include a differential pressure reduction hole (227a) that is connected to each of the inflow space (IS) and the outflow space (OS). The differential pressure reduction hole (227a) may correspond to an internal space of the partition (227). When the partition (227) is formed by extending along the first axial direction (X-axis direction), the differential pressure reduction hole (227a) may be formed by penetrating the partition (227) along the first axial direction (X-axis direction).

[0061] Since the above pressure reduction hole (227a) is connected to each of the inlet space (IS) and the outlet space (OS), a portion of the first gas introduced into the mid-case (21) through the mid inlet (212) may be introduced into the compartment (227), flow along the pressure reduction hole (227a), and then be introduced into the outlet space (OS). In this case, another portion of the first gas introduced into the mid-case (21) through the mid inlet (212) may be introduced into the sub-cartridges (22a, 22b) from the inlet space (IS), exchange moisture with the second gas while flowing along the sub-cartridges (22a, 22b), and then be introduced into the outlet space (OS).

[0062] In this way, the cartridge (22) is implemented to perform a humidifying function by exchanging moisture with the second gas while the first gas flows between the hollow fiber membrane bundles (221a, 221b) using the sub-cartridges (22a, 22b), and at the same time, the cartridge (222) is implemented to perform a shell pressure reduction function by allowing the first gas to flow along the pressure reduction hole (227a) without being affected by the hollow fiber membrane bundles (221a, 221b) using the partition (227).

[0063] Accordingly, the fuel cell humidifier (1) according to the present invention can achieve the following effects.

[0064] First, the fuel cell humidifier (1) according to the present invention can prevent the shell differential pressure from increasing excessively by using the differential pressure reduction hole (227a) during the process in which the first gas introduced into the inflow space (IS) flows through the interior of the cartridge (22) to the outflow space (OS). Accordingly, the fuel cell humidifier (1) according to the present invention can reduce the amount of electricity generated in the fuel cell system used by the compressor side for the flow of the first gas, and thus can contribute to improving the overall efficiency of the fuel cell system.

[0065] Second, since the fuel cell humidifier (1) according to the present invention can divide the cartridge (22) into the sub-cartridges (22a, 22b) by using the partition (227), the size of the internal cross-sectional area of ​​each of the sub-cartridges (22a, 22b) can be reduced. The internal cross-sectional area of ​​each of the sub-cartridges (22a, 22b) may be a cross-sectional area based on the third axial direction (Z-axis direction). The third axial direction (Z-axis direction) is an axial direction perpendicular to each of the first axial direction (X-axis direction) and the second axial direction (Y-axis direction). As the size of the internal cross-sectional area of ​​each of the sub-cartridges (22a, 22b) decreases, the size of the hollow fiber membrane bundles (221a, 221b) accommodated in the sub-cartridges (22a, 22b) also decreases with respect to the third axial direction (Z-axis direction). Therefore, the fuel cell humidifier (1) according to the present invention can increase the number of hollow fiber membranes that come into contact with the first gas and participate in humidification among the hollow fiber membranes of each of the hollow fiber membrane bundles (221a, 221b). Accordingly, the fuel cell humidifier (1) according to the present invention can improve the overall humidification efficiency by improving the humidification efficiency of each of the sub-cartridges (22a, 22b).

[0066] The partition (227) can partition the interior of the inner case (222) into the sub-cartridges (22a, 22b) based on the second axial direction (Y-axis direction). For example, the partition (227) can be arranged between a first sub-cartridge (22a) among the sub-cartridges (22a, 22b) and a second sub-cartridge (22b) among the sub-cartridges (22a, 22b). A first hollow fiber membrane bundle (221a) among the hollow fiber membrane bundles (221a, 221b) can be accommodated in the first sub-cartridge (22a). A second hollow fiber membrane bundle (221b) among the hollow fiber membrane bundles (221a, 221b) can be accommodated in the second sub-cartridge (22b). The above-mentioned partition (227) may be implemented as a plurality of partition plates that partition a portion of the inner case (222) and the interior of the inner case (222). The partition (227) may also be implemented separately from the inner case (222). In this case, the partition (227) may be formed in a cylindrical shape with an entirely empty interior.

[0067] The above-mentioned partition (227) may be implemented so as not to accommodate the hollow fiber membrane bundle (221). Accordingly, the pressure reduction hole (227a) is empty. Accordingly, the partition (227) can introduce a portion of the first gas introduced into the inflow space (IS) through the empty pressure reduction hole (227a) and then discharge it into the discharge space (OS). Accordingly, the partition (227) can reduce the shell pressure difference by utilizing the pressure reduction hole (227a), thereby contributing to improving the overall efficiency of the fuel cell system.

[0068] The above-mentioned partition (227) can be sealed at both ends by the first fixed layer (223) and the second fixed layer (224). In this case, the first fixed layer (223) can seal one end of the differential pressure reducing hole (227a), thereby sealing one end of the partition (227). The second fixed layer (224) can seal the other end of the differential pressure reducing hole (227a), thereby sealing the other end of the partition (227). In this way, since both ends of the differential pressure reducing hole (227a) are sealed, the partition (227) can induce the first gas introduced from the inflow space (IS) into the differential pressure reducing hole (227a) to flow out to the outflow space (OS).

[0069] The above-mentioned partition (227) may be implemented so that the differential pressure reduction hole (227a) and the inflow space (IS) are communicated through the inner inflow port (225). In this case, the inner inflow port (225) may include a first inflow window (225b) that communicates the sub-cartridges (22a, 22b) and the inflow space (IS), and a second inflow window (225c) that communicates the differential pressure reduction hole (227a) and the inflow space (IS). Accordingly, a portion of the first gas may be introduced into the sub-cartridges (22a, 22b) from the inflow space (IS) through the first inflow window (225b), and another portion of the first gas may be introduced into the differential pressure reduction hole (227a) from the inflow space (IS) through the second inflow window (225c). The first inflow window (225b) and the second inflow window (225c) may belong to the inflow windows (225a). The first inflow window (225b) and the second inflow window (225c) may each be provided in multiples. When the partition (227) is implemented separately from the inner case (222), the second inflow window (225c) may be formed by penetrating both the inner case (222) and the partition (227).

[0070] The above-mentioned partition (227) may be implemented so that the differential pressure reduction hole (227a) and the outlet space (OS) are connected through the inner outlet (226). In this case, the inner outlet (226) may include a first outlet window (226b) that connects the sub-cartridges (22a, 22b) and the outlet space (OS), and a second outlet window (226c) that connects the differential pressure reduction hole (227a) and the outlet space (OS). Accordingly, the first gas introduced into the interior of the sub-cartridges (22a, 22b) may be discharged into the outlet space (OS) through the first outlet window (226b), and the first gas introduced into the interior of the partition (227) may be discharged into the outlet space (OS) through the second outlet window (226c). The first outlet window (226b) and the second outlet window (226c) may belong to the outlet windows (226a). The first outlet window (226b) and the second outlet window (226c) may each be provided in multiples. When the partition (227) is implemented separately from the inner case (222), the second outlet window (226c) may be formed by penetrating both the inner case (222) and the partition (227).

[0071] Meanwhile, when the internal cross-sectional area (ICS) of the inner case (222) is defined as 1, the cross-sectional area (CS) of the differential pressure reduction hole (227a) may be 0.3 or less. In this case, the cross-sectional area (CS) of the differential pressure reduction hole (227a) may be formed to be 0.3 times or less than the internal cross-sectional area (ICS) of the inner case (222). The cross-sectional area (CS) of the differential pressure reduction hole (227a) and the internal cross-sectional area (ICS) of the inner case (222) may each be cross-sectional areas based on the third axial direction (Z-axis direction). When the cross-sectional area (CS) of the pressure reduction hole (227a) is formed to be more than 0.3 times the internal cross-sectional area (ICS) of the inner case (222), the density of the hollow fiber membrane bundles (221a, 221b) accommodated in the sub-cartridges (22a, 22b) increases further, so that the shell pressure difference between the inlet space (IS) and the outlet space (OS) may increase. In this case, if the number of hollow fiber membranes of the hollow fiber membrane bundles (221a, 221b) accommodated in the sub-cartridges (22a, 22b) is reduced, the humidification performance may deteriorate. In consideration of this, the fuel cell humidifier (1) according to the present invention can reduce the shell differential pressure and improve the humidification performance by being implemented so that the cross-sectional area (CS) of the differential pressure reduction hole (227a) is formed to be 0.3 times or less compared to the internal cross-sectional area (ICS) of the inner case (222). When the internal cross-sectional area (ICS) of the inner case (222) is defined as 1, when the cross-sectional area (CS) of the differential pressure reduction hole (227a) is formed to be 0.3, the fuel cell humidifier (1) according to the present invention can be implemented so as to have approximately the same humidification performance while reducing the shell differential pressure by 30% compared to a comparative example without the partition (227).

[0072] The cartridge (22) may include a plurality of partitions (227). The partitions (227, 227') (illustrated in FIG. 11) may be arranged at positions spaced apart from each other. Accordingly, the partitions (227, 227') can implement a shell differential pressure reduction function at different positions, thereby further reducing the shell differential pressure applied to the inlet space (IS) and the outlet space (OS). Due to the partitions (227, 227'), the number of the sub-cartridges (22a, 22b, 22c) (illustrated in FIG. 11) also increases, thereby reducing the internal cross-sectional area of ​​each of the sub-cartridges (22a, 22b, 22c). Accordingly, the fuel cell humidifier (1) according to the present invention can further increase the number of hollow fiber membranes that come into contact with the first gas and participate in humidification in each of the sub-cartridges (22a, 22b, 22c), thereby further improving the overall humidification efficiency.

[0073] The above-described compartments (227, 227') may be arranged at positions spaced apart from each other along the second axial direction (Y-axis direction). Accordingly, a plurality of sub-cartridges (22a, 22b, 22c) (as shown in FIG. 11) may be arranged at positions spaced apart from each other along the second axial direction (Y-axis direction). Although FIG. 11 illustrates that the cartridge (22) includes two compartments (227, 227') and three sub-cartridges (22a, 22b, 22c), the present invention is not limited thereto, and the cartridge (22) may be implemented to include three or more compartments (227) and four or more sub-cartridges. In this case, the number of the sub-cartridges may be one more than the number of compartments (227).

[0074] Meanwhile, when the cartridge (22) includes a plurality of the compartments (227), when the internal cross-sectional area (ICS) of the inner case (222) is defined as 1, the sum of the cross-sectional areas (CS) of the pressure reduction holes (227a) of the compartments (227) can be formed to be 0.3 or less. That is, the sum of the cross-sectional areas (CS) of the pressure reduction holes (227a) can be formed to be 0.3 times or less compared to the internal cross-sectional area (ICS) of the inner case (222).

[0075] Referring to FIGS. 7 to 10, the partition (227) may include a first communication hole (227b).

[0076] The first communication hole (227b) may be connected to the first sub-cartridge (22a). Accordingly, the first gas may be implemented to flow between the differential pressure reduction hole (227a) and the first sub-cartridge (22a) through the first communication hole (227b). When the internal pressure of the first sub-cartridge (22a) excessively increases, the first gas may flow from the first sub-cartridge (22a) to the differential pressure reduction hole (227a) through the first communication hole (227b). Accordingly, the first communication hole (227b) may prevent the internal pressure of the first sub-cartridge (22a) from excessively increasing. When the internal pressure of the first sub-cartridge (22a) is excessively reduced, the first gas can flow from the pressure reduction hole (227a) to the first sub-cartridge (22a) through the first communication hole (227b). Accordingly, the first communication hole (227a) can prevent the internal pressure of the first sub-cartridge (22a) from being excessively reduced. In this way, the cartridge (22) can be implemented so that the internal pressure of the first sub-cartridge (22a) is controlled within a preset range by using the first communication hole (227b).

[0077] The above-described partition (227) may include a plurality of first communication holes (227b). The first communication holes (227b, 227b') may communicate with the insides of different sub-cartridges (22a, 22b). When the first communication hole (227b) is communicated with the first sub-cartridge (22a), the first communication hole (227b') may be communicated with the second sub-cartridge (22b). Accordingly, the cartridge (22) may be implemented so that the internal pressure of the first sub-cartridge (22a) and the internal pressure of the second sub-cartridge (22b) are each controlled within a preset range by using the first communication holes (227b, 227b').

[0078] Referring to FIGS. 7 to 10, the partition (227) may include a second communication hole (227c).

[0079] The second communication hole (227c) may be connected to the first sub-cartridge (22a). Accordingly, the first gas may be implemented to flow between the pressure reduction hole (227a) and the first sub-cartridge (22a) through the second communication hole (227c). The second communication hole (227c) may be arranged closer to the outlet space (OS) than to the inlet space (IS). In this case, the first communication hole (227b) may be arranged closer to the inlet space (IS) than to the outlet space (OS). Accordingly, the cartridge (22) can be implemented so that the first gas flows between the differential pressure reduction hole (227a) and the first sub-cartridge (22a) on the inflow space (IS) side and the outflow space (OS) side by using the second communication hole (227c) and the second communication hole (227b). Accordingly, the cartridge (22) can further improve the ease and accuracy of the operation of controlling the internal pressure of the first sub-cartridge (22a) within a preset range.

[0080] The above-described partition (227) may include a plurality of second communication holes (227c). The second communication holes (227c, 227c') may be in communication with the interiors of different sub-cartridges (22a, 22b). When the second communication hole (227c) is in communication with the first sub-cartridge (22a), the second communication hole (227c') may be in communication with the second sub-cartridge (22b). Accordingly, the cartridge (22) can further improve the ease and accuracy of the operation of controlling the internal pressure of the first sub-cartridge (22a) and the internal pressure of the second sub-cartridge (22b) within a preset range by using the second communication holes (227c, 227c') and the first communication holes (227b, 227b').

[0081] The present invention described above is not limited to the above-described embodiments and the attached drawings, and it will be apparent to a person skilled in the art to which the present invention pertains that various substitutions, modifications, and changes are possible within a scope that does not depart from the technical spirit of the present invention.

[0082] [Explanation of symbols]

[0083] 1: Humidifier for fuel cell

[0084] 2: Humidification Module 21: Mid-Case

[0085] 210: Midbody 211: Receiving hole

[0086] 212: Mid inlet 213: Mid outlet

[0087] 22: Cartridge 22a: First sub-cartridge

[0088] 22b: Second sub-cartridge 221: Hollow fiber desert bundle

[0089] 221a: 1st hollow fiber bundle 221b: 2nd hollow fiber bundle

[0090] 222: Inner case 223: First fixed layer

[0091] 224: Second fixed layer 225: Inner inlet

[0092] 225a: Inlet window 225b: First inlet window

[0093] 225c: Second inlet window 226: Inner outlet

[0094] 226a: Leakage window 226b: First leakage window

[0095] 226c: Second leak window 227, 227': Compartment

[0096] 227a, 227a': pressure reduction hole 227b, 227b': first communication hole

[0097] 227c, 227c': Second communication hole 23: First packing section

[0098] 231: First insertion hole 24: Second packing part

[0099] 241: Second insertion hole 25: Bulkhead

[0100] 3: 1st cap 31: 1st port

[0101] 4: Second cap 41: Second port

[0102] IS: Inflow space OS: Outflow space

[0103] CS: Cross-sectional area of ​​the pressure reducing hole ICS: Internal cross-sectional area of ​​the inner case

Claims

1. Humidification module; A first cap coupled to one end of the above humidifying module; and a second cap coupled to the other end of the above humidifying module; The above humidifying module, Mid-case with both ends open; At least one cartridge accommodated inside the mid-case; and It includes a partition wall that divides the interior of the above mid-case into an inlet space where the first gas flows in and an outlet space where the first gas flows out; The above cartridge, Inner Case having openings at both ends; A compartment that divides the interior of the inner case into multiple sub-cartridges; and A plurality of hollow fiber membrane bundles each accommodated in each of the plurality of sub-cartridges; A fuel cell humidifier, wherein the above compartment includes a pressure reduction hole connected to each of the inflow space and the outflow space.

2. In the first paragraph, the cartridge, An inner inlet for introducing a first gas into the interior of the inner case; and A humidifier for a fuel cell, comprising an inner outlet for discharging a first gas from the inside of the inner case, the inner outlet being spaced apart from the inner inlet along the first axial direction.

3. In the second paragraph, the inner inlet is A first inlet window connecting each of the sub-cartridges with the inlet space; and A humidifier for a fuel cell, comprising a second inflow window connecting the pressure reduction hole and the inflow space.

4. In the second paragraph, the inner outlet is A first discharge window connecting each of the sub-cartridges with the discharge space; and A humidifier for a fuel cell, comprising a second outlet window connecting the pressure reduction hole and the outlet space.

5. In paragraph 1, The above cartridge, A first fixed layer for fixing one end of the above hollow fiber bundles; and A second fixed layer for fixing the other end of the above hollow fiber bundles; The above first fixed layer seals one end of the pressure reduction hole, A fuel cell humidifier, wherein the second fixed layer seals the other end of the pressure reduction hole.

6. In paragraph 1, A fuel cell humidifier, wherein the above-mentioned compartment is configured to introduce a portion of the first gas introduced into the inflow space through the pressure reduction hole and then discharge the gas into the discharge space.

7. In paragraph 1, A fuel cell humidifier, wherein when the internal cross-sectional area of ​​the inner case is defined as 1, the cross-sectional area of ​​the pressure reduction hole is 0.3 or less.

8. In paragraph 1, The above cartridge comprises a plurality of compartments, A humidifier for a fuel cell, wherein the above compartments are arranged at positions spaced apart from each other.

9. In paragraph 8, A fuel cell humidifier, wherein the sum of the cross-sectional areas of the pressure reduction holes of the compartments is 0.3 or less when the internal cross-sectional area of ​​the inner case is defined as 1.

10. In paragraph 1, The above plurality of sub-cartridges include a first sub-cartridge and a second sub-cartridge, A humidifier for a fuel cell, wherein the compartment is disposed between the first sub-cartridge and the second sub-cartridge.

11. In paragraph 10, The above plurality of hollow fiber membrane bundles include a first hollow fiber membrane bundle and a second hollow fiber membrane bundle, The first sub-cartridge accommodates the first hollow fiber membrane bundle, A humidifier for a fuel cell, wherein the second sub-cartridge accommodates the second hollow fiber membrane bundle.

12. In paragraph 10, A humidifier for a fuel cell, wherein the compartment includes a first communication hole communicating with the interior of the first sub-cartridge.

13. In paragraph 12, A humidifier for a fuel cell, wherein the compartment includes a second communication hole communicating with the interior of the first sub-cartridge.

14. In paragraph 13, The above first communication hole is positioned closer to the inflow space than to the outflow space, A fuel cell humidifier, wherein the second communication hole is positioned closer to the outlet space than to the inlet space.

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