Cartridge for a fuel cell humidifier and fuel cell humidifier

Abstract

The present invention relates to: a cartridge for a fuel cell humidifier, which is used to humidify a dry gas supplied from the outside by using a wet gas discharged from a fuel cell stack; and a fuel cell humidifier, the cartridge including: an inner case having an opening at an end portion thereof and having a plurality of hollow fiber membranes accommodated therein; and a first gas inlet and a first gas outlet formed in the inner case so as to be spaced apart from each other in a first axis direction, wherein: the inner case includes a first section in which the hollow fiber membranes are accommodated, a second section spaced apart from the first section based on a second axis direction perpendicular with respect to the first axis direction, and a third section located between the first section and the second section based on the second axis direction; and an average thickness of the third section is thinner than each of an average thickness of the first section and an average thickness of the second section.

Description

Technical Field

[0001] This disclosure relates to a humidifier for a fuel cell, configured to supply humidifying gas to the fuel cell. Background Technology

[0002] Unlike conventional chemical batteries such as dry cell batteries or storage batteries, fuel cells have the advantage of being able to continuously generate electricity as long as hydrogen and oxygen are supplied, and have an efficiency that is about twice as high as that of internal combustion engines due to the absence of heat loss.

[0003] Furthermore, fuel cells directly convert the chemical energy generated by the combination of hydrogen and oxygen into electrical energy, resulting in low levels of pollutants. Therefore, fuel cells offer the advantage of being environmentally friendly and reducing concerns about resource depletion due to increased energy consumption.

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

[0005] These fuel cells operate on essentially the same principle, but differ in the type of fuel used, operating temperature, catalyst, and electrolyte. Among these fuel cells, polymer electrolyte membrane fuel cells (PEMFCs) are considered the most suitable for transportation systems and small stationary power generation devices because they operate at lower temperatures and have higher output densities than other fuel cells, allowing for miniaturization.

[0006] One of the most important factors in improving the performance of polymer electrolyte membrane fuel cells (PEMFCs) is supplying a predetermined amount or more of moisture to the polymer electrolyte membrane or proton exchange membrane (PEM) of the membrane electrode module (MEA) to maintain its moisture content. This is because if the polymer electrolyte membrane or proton exchange membrane is dry, the power generation efficiency drops sharply.

[0007] 1) A bubbling humidification method that fills a pressure-resistant container with water and allows the target gas to pass through a diffuser to supply moisture; 2) A direct injection method that calculates the amount of moisture required for the fuel cell reaction and supplies moisture directly to the gas flow pipe via a solenoid valve; and 3) A membrane humidification method that uses a polymer separation membrane to supply moisture to a gas fluidized bed as a method for humidifying polymer electrolyte membranes or proton exchange membranes.

[0008] Among these methods, membrane humidification humidification humidifies the polymer electrolyte membrane or proton exchange membrane by using a membrane configured to selectively permeate water vapor contained in the exhaust gas into the air supplied to the membrane. This method has the advantage of reducing the weight and size of the humidifier.

[0009] When forming modules, hollow fiber membranes with a large transmission area per unit volume are suitable for selective permeation membranes used in membrane humidification methods. That is, when using hollow fiber membranes to manufacture membrane humidifiers, the high integration of hollow fiber membranes with large contact surface areas is possible, thereby enabling sufficient humidification of fuel cells even at small capacities, the use of inexpensive materials, and the collection of moisture and heat contained in the exhaust gas discharged from the fuel cell at high temperatures, which can then be reused by the humidifier.

[0010] Figure 1 This is a schematic exploded perspective view of a conventional humidifier used in fuel cells.

[0011] like Figure 1 As shown, a conventional membrane humidification humidifier 100 includes: a humidification module 110 in which moisture is exchanged between externally supplied air and exhaust gas discharged from a fuel cell stack (not shown); and a cover 120, respectively engaged with opposite ends of the humidification module 110.

[0012] One of the covers 120 transmits externally supplied air to the humidification module 110, while the other cover transmits humidified air from the humidification module 110 to the fuel cell stack.

[0013] The humidification module 110 includes an intermediate housing 111 having an exhaust gas inlet 111a and an exhaust gas outlet 111b, and a plurality of hollow fiber membranes 112 within the intermediate housing 111. The opposite ends of a bundle of hollow fiber membranes 112 are encapsulated in fixed layers 113. Typically, each fixed layer 113 is formed by using a casting method to cure a liquid polymer, such as liquid polyurethane resin. The fixed layers 113 encapsulating the ends of the hollow fiber membranes 112, and a resin layer 114 disposed between the fixed layers 113 and the intermediate housing 111, isolate the internal space of the cover 120 from the internal space of the intermediate housing 111. Similar to the fixed layers 113, each resin layer 114 is typically formed by using a casting method to cure a liquid polymer, such as liquid polyurethane resin.

[0014] Externally supplied air flows along the hollow core of the hollow fiber membrane 112. Exhaust gas introduced into the intermediate shell 111 through exhaust gas inlet 111a contacts the outer surface of the hollow fiber membrane 112 and is discharged from the intermediate shell 111 through exhaust gas outlet 111b. When the exhaust gas contacts the outer surface of the hollow fiber membrane 112, moisture contained in the exhaust gas is transferred through the hollow fiber membrane 112 to humidify the air flowing along the hollow core of the hollow fiber membrane 112.

[0015] As is customary, humidification is concentrated through the relatively outer hollow fiber membrane of the hollow fiber membrane 112, while humidification cannot be carried out smoothly through the relatively inner hollow fiber membrane of the hollow fiber membrane 112, resulting in low overall humidification performance. Summary of the Invention

[0016] Technical issues

[0017] This disclosure is made in view of the above-mentioned problems, and the purpose of this disclosure is to provide a cylinder for a fuel cell humidifier and a humidifier for a fuel cell that can use a hollow fiber membrane to improve humidification performance.

[0018] Technical solution

[0019] To achieve the above objectives, this disclosure may include the following construction.

[0020] A humidifier for a fuel cell according to this disclosure may include: a humidification module configured to humidify dry gas supplied from the outside using wet gas discharged from a fuel cell stack; a first cover engaged to one end of the humidification module; and a second cover engaged to the other end of the humidification module. The humidification module may include an intermediate housing open at its opposite ends and at least one cylindrical body disposed within the intermediate housing, the cylindrical body comprising a plurality of hollow fiber membranes. The cylindrical body may include: an inner housing open at its opposite ends, the hollow fiber membranes being housed within the inner housing; and a first gas inlet and a first gas outlet formed on the inner housing to be spaced apart from each other in a first axial direction. The inner housing may include a first segment in which the hollow fiber membranes are housed, a second segment spaced apart from the first segment in a second axial direction perpendicular to the first axial direction, and a third segment located between the first and second segments in the second axial direction. The average thickness of the third segment may be less than each of the average thickness of the first segment and the average thickness of the second segment.

[0021] The cylinder for a fuel cell humidifier according to this disclosure can be a cylinder for a fuel cell humidifier configured to humidify externally supplied dry gas using wet gas discharged from a fuel cell stack. The cylinder includes: an inner shell having openings formed at its ends, a plurality of hollow fiber membranes housed within the inner shell; and a first gas inlet and a first gas outlet formed on the inner shell to be spaced apart from each other in a first axial direction. The inner shell may include a first segment in which the hollow fiber membranes are housed, a second segment spaced apart from the first segment in a second axial direction perpendicular to the first axial direction, and a third segment located between the first and second segments in the second axial direction. The average thickness of the third segment may be less than each of the average thickness of the first segment and the average thickness of the second segment.

[0022] Beneficial effects

[0023] This disclosure can be implemented to enable smooth humidification of the entire hollow fiber membrane. Therefore, in this disclosure, the proportion of hollow fiber membrane used for humidification can be increased, thereby increasing the overall humidification performance. Attached Figure Description

[0024] Figure 1 This is a schematic exploded perspective view of a conventional humidifier used in fuel cells.

[0025] Figure 2 This is a schematic exploded perspective view of a humidifier for a fuel cell according to the present disclosure.

[0026] Figure 3 It is along Figure 2 Line II shows a schematic cutaway view of a humidifier for a fuel cell according to this disclosure.

[0027] Figure 4 It is along Figure 2 Line II shows a schematic joined cross-sectional view of a humidifier for a fuel cell according to this disclosure.

[0028] Figure 5 This is a schematic plan view of a fuel cell humidifier cylinder according to the present disclosure.

[0029] Figure 6 It is along Figure 5 Line II-II shows a schematic side sectional view of the cylinder for a fuel cell humidifier according to this disclosure.

[0030] Figure 7 It is along Figure 5 Line III-III shows a schematic side sectional view of the cylinder for a fuel cell humidifier according to this disclosure.

[0031] Figure 8 It is along Figure 5 The schematic side sectional view of the cylinder according to the comparative example is shown by line III-III.

[0032] Figure 9 It is along Figure 5 Line III-III shows a schematic side sectional view of the cylinder for a fuel cell humidifier according to a modified embodiment of the present disclosure.

[0033] Figure 10 It is along Figure 5 Line II-II shows a schematic side sectional view of the cylinder for a fuel cell humidifier according to this disclosure.

[0034] Figure 11 It is along Figure 5 A schematic enlarged side sectional view of the first buffer member in the cylinder of the fuel cell humidifier according to the present disclosure, taken from line II-II.

[0035] Figure 12 It is along Figure 5 A schematic enlarged side sectional view of the second buffer member in the cylinder of the fuel cell humidifier according to the present disclosure, taken from line II-II.

[0036] Figure 13 and Figure 14 This is a schematic partial cross-sectional view showing the state of the cylinder located in the intermediate shell. Detailed Implementation

[0037] Hereinafter, embodiments of the humidifier for fuel cells according to the present disclosure will be described in detail with reference to the accompanying drawings. The cylinder of the humidifier for fuel cells according to the present disclosure may be included within the humidifier for fuel cells according to the present disclosure; therefore, the cylinder of the humidifier for fuel cells according to the present disclosure will also be described concurrently with the description of the humidifier for fuel cells according to the present disclosure. Meanwhile, in Figure 6 , Figure 10 , Figure 13 and Figure 14 In the image, the two parallel curves are ellipses.

[0038] refer to Figures 2 to 4The humidifier 1 for a fuel cell according to this disclosure is configured to humidify dry gas supplied from the outside using humid gas discharged from a fuel cell stack (not shown). The dry gas can be fuel gas or air. The dry gas can be humidified by the humid gas and can be supplied to the fuel cell stack. The humidifier 1 for a fuel cell according to this disclosure includes: a humidification module 2 configured to humidify dry gas, a first cover 3 engaged to one end of the humidification module 2, and a second cover 4 engaged to the other end of the humidification module 2.

[0039] refer to Figures 2 to 6 The humidification module 2 humidifies the dry gas supplied from the outside. A first cover 3 can be attached to one end of the humidification module 2. A second cover 4 can be attached to the other end of the humidification module 2. The first cover 3 can transmit dry gas to the humidification module 2. In this case, the second cover 4 can transmit dry gas humidified by the humidified gas in the humidification module 2 to the outside. The first cover 3 can transmit humidified gas to the humidification module 2. In this case, after the dry gas is humidified in the humidification module 2, the second cover 4 can discharge the humidified gas to the outside.

[0040] The humidification module 2 includes at least one cylinder 21 and an intermediate shell 22.

[0041] The cylindrical body 21 is disposed within the intermediate housing 22 and includes a plurality of hollow fiber membranes 211. The hollow fiber membranes 211 can be joined to the cylindrical body 21 for modularity. Therefore, the hollow fiber membranes 211 can be installed in the intermediate housing 22 by joining the cylindrical body 21 to the intermediate housing 22. Thus, in the humidifier 1 for a fuel cell according to the present disclosure, the ease of installation, separation, and replacement of the hollow fiber membranes 211 can be improved.

[0042] The cylindrical body 21 may include an inner shell 212.

[0043] The inner housing 212 has openings formed at its ends, and a plurality of hollow fiber membranes 211 are housed within the inner housing. The hollow fiber membranes 211 may be disposed within the inner housing 212 for modularity. The hollow fiber membranes 211 may comprise polymer membranes made of polysulfone resin, polyethersulfone resin, sulfonated polysulfone resin, polyvinylidene fluoride (PVDF) resin, polyacrylonitrile (PAN) resin, polyimide resin, polyamide-imide resin, polyesterimide resin, or mixtures of two or more thereof.

[0044] The cylinder 21 may include a fixing layer 213 and a fixing layer 214.

[0045] The ends of a plurality of hollow fiber membranes 211 are encapsulated in fixing layers 213 and 214, which close the openings of the inner housing 212. One side of each of the plurality of hollow fiber membranes 211 can be fixed by fixing layer 213, and the other side of each of the plurality of hollow fiber membranes 211 can be fixed by fixing layer 214. Each of fixing layers 213 and 214 can be formed by curing a liquid resin, such as liquid polyurethane resin, through a casting process. Fixing layers 213 and 214 can fix the ends of the plurality of hollow fiber membranes 211 to the inner housing 212.

[0046] The fixing layers 213 and 214 can be formed in a way that does not obstruct the hollow spaces of the plurality of hollow fiber membranes 211. Therefore, dry or wet gas supplied from the outside can be supplied to the hollow spaces of the hollow fiber membranes 211 without interference from the fixing layers 213 and 214, and can be discharged from the hollow spaces of the hollow fiber membranes 211 without interference from the fixing layers 213 and 214.

[0047] The cylinder 21 may include a first gas inlet 215 and a first gas outlet 216.

[0048] A first gas inlet 215 is formed in the inner casing 212. The first gas inlet 215 may be formed on one side 2120 of the inner casing 212. Based on... Figure 6 One side 2120 of the inner housing 212 may correspond to the upper surface. A first gas inlet 215 allows either wet or dry gas to be introduced into the inner housing 212. The first gas inlet 215 may be formed through the inner housing 212. The first gas inlet 215 may be implemented by a plurality of through-holes formed through the inner housing 212. In this case, the first gas inlet 215 may include a plurality of inflow windows 215a formed through different portions of the inner housing 212. The inflow windows 215a may be spaced apart from each other in a first axial direction (X-axis direction) and a second axial direction (Y-axis direction) to form a matrix. The first axial direction and the second axial direction (Y-axis direction) are axial directions perpendicular to each other. Although not shown, the first gas inlet 215 may be implemented by a single through-hole formed through the inner housing 212.

[0049] A first gas outlet 216 is formed in the inner housing 212. The first gas outlet 216 may be formed on one side 2120 of the inner housing 212. The first gas outlet 216 allows humid or dry gas to exit from the inner housing 212. The first gas outlet 216 may be formed through the inner housing 212. The first gas outlet 216 may be implemented by a plurality of through-holes formed through the inner housing 212. In this case, the first gas outlet 216 may include a plurality of outflow windows 216a formed through different portions of the inner housing 212. The outflow windows 216a may be spaced apart from each other in a first axial direction (X-axis direction) and a second axial direction (Y-axis direction) to form a matrix. Although not shown, the first gas outlet 216 may be implemented by a single through-hole formed through the inner housing 212.

[0050] The first gas outlet 216 and the first gas inlet 215 can be spaced apart from each other in the first axial direction (X-axis direction). Therefore, humid gas can be supplied to the intermediate shell 22, and can be supplied to the inner shell 212 through the first gas inlet 215. It can contact the outer surface of the hollow fiber membrane 211, humidify the dry gas flowing along the hollow structure of the hollow fiber membrane 211, and can be discharged from the inner shell 212 through the first gas outlet 216, and can also be discharged from the intermediate shell 22. Simultaneously, dry gas can be supplied to the intermediate shell 22, and can be supplied to the inner shell 212 through the first gas inlet 215. It can contact the outer surface of the hollow fiber membrane 211, be humidified by the humid gas flowing along the hollow structure of the hollow fiber membrane 211, and can be discharged from the inner shell 212 through the first gas outlet 216, and can also be discharged from the intermediate shell 22.

[0051] The cylindrical body 21 is joined to the intermediate housing 22. The cylindrical body 21 may be disposed within the intermediate housing 22. The opposite ends of the intermediate housing 22 are open. In this case, a receiving hole 221 may be formed in the intermediate housing 22. The receiving hole 221 may be formed to extend through the intermediate housing 22 in a first axial direction (X-axis direction).

[0052] A second gas inlet 222 and a second gas outlet 223 may be formed in the intermediate housing 22. The second gas inlet 222 allows humid or dry gas to be introduced into the intermediate housing 22. The second gas outlet 223 allows humid or dry gas to be discharged from the intermediate housing 22. The second gas inlet 222 and the second gas outlet 223 may be spaced apart from each other in the first axial direction (X-axis direction).

[0053] When the wet gas flows through the second gas inlet 222 and the second gas outlet 223, the wet gas and the dry gas can flow as follows.

[0054] After being supplied to the intermediate housing 22 through the second gas inlet 222, the humid gas can be supplied to the cylinder 21 through the first gas inlet 215 and can contact the outer surface of the hollow fiber membrane 211. During this process, the moisture contained in the humid gas can be transferred through the hollow fiber membrane 211 to humidify the dry gas flowing along the hollow of the hollow fiber membrane 211. The humidified dry gas can be discharged from the hollow fiber membrane 211, discharged through the second cap 4, and can be supplied to the fuel cell stack. After humidifying the dry gas, the humid gas can be discharged from the cylinder 21 through the first gas outlet 216, can flow through the interior of the intermediate housing 22, and can be discharged from the intermediate housing 22 through the second gas outlet 223. The second gas inlet 222 can be connected to the fuel cell stack so that the humid gas is supplied to the fuel cell stack. In this case, the humid gas can be the exhaust gas discharged from the fuel cell stack.

[0055] When the dry gas flows through the second gas inlet 222 and the second gas outlet 223, the dry gas and the wet gas can flow as follows.

[0056] After being supplied to the intermediate housing 22 through the second gas inlet 222, the dry gas can be supplied to the cylinder 21 through the first gas inlet 215 and can contact the outer surface of the hollow fiber membrane 211. During this process, moisture contained in the wet gas flowing along the hollow of the hollow fiber membrane 211 can be transferred through the hollow fiber membrane 211 to humidify the dry gas. The humidified dry gas can be discharged from the cylinder 21 through the first gas outlet 216, can flow through the interior of the intermediate housing 22, can be discharged from the intermediate housing 22 through the second gas outlet 223, and can be supplied to the fuel cell stack. After humidifying the dry gas, the wet gas can be discharged from the hollow fiber membrane 211 and can be discharged to the outside through the second cover 4. The first cover 3 can be connected to the fuel cell stack so that the wet gas is supplied to the fuel cell stack. In this case, the wet gas can be exhaust gas discharged from the fuel cell stack.

[0057] The second gas inlet 222 and the second gas outlet 223 may protrude from the intermediate body 220. The intermediate body 220 forms the overall appearance of the intermediate shell 22. The second gas inlet 222 and the second gas outlet 223 may protrude from the intermediate body 220 in the same direction. Alternatively, the second gas inlet 222 and the second gas outlet 223 may protrude from the intermediate body 220 in different directions. The second gas inlet 222, the second gas outlet 223, and the intermediate body 220 may be integrally formed.

[0058] The humidification module 2 may include multiple filling members 23 and filling members 23'.

[0059] Filler members 23 and 23' form an airtight seal between the cylinder 21 and the intermediate shell 22 to prevent direct mixing of dry and wet gases. Filler members 23 and 23' can be inserted between the cylinder 21 and the intermediate shell 22. In this case, the cylinder 21 can be inserted through first through holes 23a and 23a' formed respectively in filler members 23 and 23a'. Filler members 23 and 23' can be respectively disposed on opposite sides of the cylinder 21. Although not shown, resin layers can be formed on opposite sides of the cylinder 21, rather than on filler members 23 and 23'. Each resin layer can be formed by using a casting method to harden a liquid polymer such as liquid polyurethane resin.

[0060] refer to Figures 2 to 4 The first cover 3 is attached to one end of the humidification module 2. The space between the first cover 3 and the cylinder 21 can be isolated from the space between the cylinder 21 and the intermediate shell 22 by the filling member 23 or the resin layer in an airtight seal.

[0061] refer to Figures 2 to 4 The second cover 4 is joined to the other end of the humidification module 2. The second cover 4 can be joined to the other end of the humidification module 2 so as to be spaced apart from the first cover 3 in the first axial direction (X-axis direction). The space between the second cover 4 and the cylinder 21 can be isolated from the space between the cylinder 21 and the intermediate shell 22 in an airtight seal by a filling member 23' or a resin layer.

[0062] refer to Figures 2 to 8 In order to improve the humidification performance of the humidifier 1 for fuel cells according to the present disclosure, the cylinder 21 may be implemented as follows.

[0063] The cylindrical body 21 can be formed to have a non-uniform thickness in the second axial direction (Y-axis direction). In this case, the inner shell 212 may include a first segment 2121, a second segment 2122, and a third segment 2123.

[0064] Hollow fiber membrane 211 is housed in each of the first segment 2121, the second segment 2122, and the third segment 2123. The first segment 2121, the second segment 2122, and the third segment 2123 can be arranged side by side in the second axial direction (Y-axis direction). In this case, the third segment 2123 can be arranged between the first segment 2121 and the second segment 2122 in the second axial direction (Y-axis direction). The first segment 2121 and the second segment 2122 can be spaced apart from each other with the third segment 2123 inserted between the first segment 2121 and the second segment 2122.

[0065] The average thickness of the third segment 2123 can be implemented to be less than the average thickness of each of the first segment 2121 and the second segment 2122. In this case, the average thickness is the average of the thicknesses of each of the third segment 2123, the second segment 2122, and the first segment 2121 in the second axial direction (Y-axis direction). When the first axial direction (X-axis direction) is defined as the longitudinal direction of the inner housing 212 and the second axial direction (Y-axis direction) is defined as the transverse direction of the inner housing 212, the thickness is the length in the third axial direction (Z-axis direction) perpendicular to each of the first axial direction (X-axis direction) and the second axial direction (Y-axis direction). When the thickness of each of the third segment 2123, the second segment 2122, and the first segment 2121 varies in the second axial direction (Y-axis direction), each of the third segment 2123, the second segment 2122, and the first segment 2121 may include a portion having a thickness equal to the average thickness, a portion having a thickness greater than the average thickness, and a portion having a thickness less than the average thickness. When the thickness of each of the third segment 2123, the second segment 2122 and the first segment 2121 does not change in the direction of the second axis (Y-axis direction), each of the third segment 2123, the second segment 2122 and the first segment 2121 may include only the portion having a thickness equal to the average thickness.

[0066] Since the average thickness of the third segment 2123 is less than the average thickness of the first segment 2121 and the average thickness of the second segment 2122, humidification is successfully achieved relative to the entire hollow fiber membrane 211, thereby improving the humidification performance of the humidifier 1 for fuel cells according to the present disclosure, which will be described in detail below.

[0067] First, such as Figure 8 As shown, in a comparative example where the inner shell 212 is implemented to be uniformly thin without thickness variation along the second axial direction (Y-axis), the hollow fiber membrane 211 located in the inner region IA cannot effectively achieve humidification compared to the hollow fiber membrane 211 located in the outer region OA. This is because humid or dry gas introduced into the inner shell 212 has difficulty passing through the hollow fiber membrane 211 in the outer region OA to reach the hollow fiber membrane 211 in the inner region IA. Therefore, in the comparative example, the proportion of hollow fiber membrane 211 used for humidification is low, resulting in low overall humidification performance. Furthermore, the inner region IA, located inside the outer region OA, can be spaced equidistantly from the opposite ends 212a and 212b of the inner shell 212 along the second axial direction (Y-axis). The inner region IA can also be spaced equidistantly from the upper and lower ends of the inner shell 212 along the third axial direction (Z-axis).

[0068] Next, as Figure 7As shown, in an example where the average thickness of the third segment 2123 is less than the average thickness of each of the first segment 2121 and the second segment 2122, compared to the comparative example ( Figure 8 The portion corresponding to the internal region IA (as shown in the example) is implemented with a smaller thickness. Therefore, in this embodiment, humid or dry gas can even be smoothly transmitted to the area compared to the comparative example (such as...). Figure 8 The hollow fiber membrane 211 in the portion corresponding to the internal region IA (shown in the diagram) enables humidification. Therefore, in this embodiment, the proportion of hollow fiber membrane 211 not used for humidification can be reduced while the proportion of hollow fiber membrane 211 used for humidification can be increased, thereby improving the overall humidification performance compared to the comparative example.

[0069] refer to Figures 2 to 7 The third segment 2123 can be formed such that the middle portion 2123a has a smaller thickness in the second axial direction (Y-axis direction) than the opposing ends 2123b and 2123c. The middle portion 2123a of the third segment 2123 is the portion spaced equidistant from the opposing ends 2123b and 2123c of the third segment 2123 in the second axial direction (Y-axis direction). Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, compared with the comparative example (such as...) Figure 8 The most difficult part to humidify, corresponding to the internal region IA (shown in the diagram), can be implemented with a smaller thickness. Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, the proportion of hollow fiber membrane 211 used for humidification can be further increased, thereby further improving the overall humidification performance.

[0070] The third segment 2123 can be formed to have a thickness that gradually increases from the middle portion 2123a to the opposite two ends 2123b and 2123c. In this case, the third segment 2123 can have a thickness that gradually increases from the middle portion 2123a in a first direction (the direction indicated by arrow FD) and can be connected to the first segment 2121 at one end 2123b. The third segment 2123 can have a thickness that gradually increases from the middle portion 2123a in a second direction (the direction indicated by arrow SD) and can be connected to the second segment 2122 at the other end 2123b. The first direction (the direction indicated by arrow FD) and the second direction (the direction indicated by arrow SD) are parallel and opposite directions in the direction of the second axis (Y-axis direction). Therefore, the third segment 2123 can be formed to have a minimum thickness 2123T at the middle portion 2123a. Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, compared with the comparative example (such as... Figure 8 The most difficult part to humidify, corresponding to the internal region IA (as shown in the diagram), can be implemented with the minimum thickness, thereby further increasing the proportion of hollow fiber membrane 211 used for humidification.

[0071] Here, the first segment 2121 can be configured such that its thickness gradually changes from one end connected to the third segment 2123 to the other end. One end of the first segment 2121 is a portion connected to one end 2123b of the third segment 2123. The other end of the first segment 2121 can correspond to one end 212a of the inner housing 212. The first segment 2121 can be configured such that its thickness gradually increases from one end to a point 2121a with a maximum thickness 2121T, and gradually decreases from the point 2121a with a maximum thickness 2121T to the other end. In this case, the first segment 2121 can have an integrally curved surface.

[0072] The second segment 2122 can be configured such that its thickness gradually changes from one end connected to the third segment 2123 to the other end. One end of the second segment 2122 is a part connected to the other end 2123c of the third segment 2123. The other end of the second segment 2122 can correspond to the other end 212b of the inner housing 212. The second segment 2122 can be configured such that its thickness gradually increases from one end to a point 2122a with a maximum thickness 2122T, and gradually decreases from the point 2122a with a maximum thickness 2122T to the other end. In this case, the second segment 2122 can have an integrally curved surface.

[0073] The inner shell 212 can be formed symmetrical to the middle portion equidistant from the opposite ends 212a and 212b in the second axial direction (Y-axis direction). The middle portion of the inner shell 212 and the middle portion 2123a of the third segment 2123 can be the same point. Therefore, based on the middle portion of the cylinder 21, the cylinder 21 can be implemented to have substantially the same humidification performance on opposite sides of the inner shell 212.

[0074] like Figure 7 As shown, the inner shell 212 can be formed as a curved surface, the thickness of which gradually increases and then decreases from the middle portion 2123a of the third segment 2123 along a first direction (indicated by arrow FD) and a second direction (indicated by arrow SD). For example, the inner shell 212 can be formed in the shape of a dumbbell. The third segment 2123, the second segment 2122, and the first segment 2121 can be formed integrally.

[0075] like Figure 9As shown, the inner shell 212 can also be formed in the form of a combination of planar surfaces. In this case, the third segment 2123 can be formed in an inclined form, such that the thickness gradually increases after extending a predetermined length from the middle portion 2123a along the first direction (indicated by arrow FD) and the second direction (indicated by arrow SD) without any change in thickness. Each of the first segment 2121 and the second segment 2122 can be formed in the shape of a cuboid with constant thickness. Although not shown, the inner shell 212 can also be formed in the form of a combination of curved surfaces and planar surfaces.

[0076] refer to Figures 2 to 9 The inner shell 212 can be formed in a form that satisfies Equation 1 below.

[0077] [Equation 1]

[0078] 0.2H <T<0.5H

[0079] In Equation 1 above, H can be the width of the inner shell 212 in the direction of the second axis (Y-axis), and T can be defined as the maximum thickness of the inner shell 212. (Reference) Figure 7 and Figure 9 H can correspond to the sum of the lengths of the first segment 2121, the second segment 2122, and the third segment 2123 in the second axial direction (Y-axis direction). T can correspond to the maximum thickness 2121T of the first segment 2121 or the maximum thickness 2122T of the second segment 2122 in the third axial direction (Z-axis direction).

[0080] Therefore, the inner shell 212 satisfying Equation 1 above can be implemented such that the maximum thickness in the third axial direction (Z-axis direction) is greater than 0.2 times and less than 0.5 times the lateral length in the second axial direction (Y-axis direction). That is, even based on the maximum thickness, the inner shell 212 can be implemented with a small thickness. Therefore, the cylinder 21 can be implemented to increase the proportion of hollow fiber membrane 211 in contact with the humid or dry gas introduced into the inner shell 212, thereby helping to improve the overall humidification performance.

[0081] In this case, when the inner shell 212 is configured such that the maximum thickness in the third axial direction (Z-axis direction) is less than 0.2 times the lateral length in the second axial direction (Y-axis direction), the capacity of the hollow fiber membrane 211 may decrease, thereby potentially deteriorating the humidification performance. When the inner shell 212 is configured such that the maximum thickness in the third axial direction (Z-axis direction) is equal to or greater than 0.5 times the lateral length in the second axial direction (Y-axis direction), the humid or dry gas introduced into the inner shell 212 may have difficulty passing between the relatively outer hollow fiber membranes in the hollow fiber membrane 211 and reaching the relatively inner hollow fiber membrane, thereby potentially deteriorating the humidification performance. With this in mind, the humidifier 1 for fuel cells according to the present disclosure has an inner housing 212 configured such that the maximum thickness in the third axial direction (Z-axis direction) is greater than 0.2 times and less than 0.5 times the lateral length in the second axial direction (Y-axis direction), thereby allowing the use of a hollow fiber membrane 211 to improve humidification performance.

[0082] Here, when humid or dry gas is introduced into and discharged from the cylinder 21, the hollow fiber membrane 211 may be vibrated by the humid or dry gas. Due to such vibration, the hollow fiber membrane 211 may directly collide with structures located nearby, thereby potentially damaging or breaking the hollow fiber membrane 211.

[0083] To reduce damage or breakage of the hollow fiber membrane 211, the cylinder 21 for the fuel cell humidifier 1 according to this disclosure may include a cushioning member 217 (such as...). Figure 10 (as shown in the image).

[0084] refer to Figures 2 to 6 and Figure 10The buffer member 217 can be engaged with the inner housing 212 so as to be located within the inner housing 212. The buffer member 217 can be engaged with the inner housing 212 at at least one of the locations between the first gas inlet 215 and the hollow fiber membrane 211 and between the first gas outlet 216 and the hollow fiber membrane 211. Therefore, even if the hollow fiber membrane 211 vibrates due to gas flow, the hollow fiber membrane 211 does not directly collide with the inner surface of the inner housing 212, but rather with the buffer member 217. Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, the impact applied to the hollow fiber membrane 211 can be mitigated, thereby reducing the risk of damage or breakage of the hollow fiber membrane 211. Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, the lifespan of the hollow fiber membrane 211 can be extended, thereby reducing maintenance costs. At the same time, the vibration generated at the hollow fiber membrane 211 may be affected by gas flow, gas pressure during gas flow, etc. In this case, the gas vibrating the hollow fiber membrane 211 can be a wet gas or a dry gas flowing through the first gas inlet 215 and the first gas outlet 216.

[0085] The buffer member 217 can be made of a breathable material configured to allow humid or dry gas to pass through while cushioning the impact applied to the hollow fiber membrane 211 due to a collision. Therefore, the buffer member 217 can be implemented to allow humid or dry gas to flow smoothly through the first gas outlet 216 and the first gas inlet 215 while cushioning the impact applied to the hollow fiber membrane 211. For example, the buffer member 217 can be made of a nonwoven material. The buffer member 217 can also be made of a mesh material.

[0086] The buffer member 217 can be joined to the inner surface of the inner housing 212. The buffer member 217 can be joined to the inner surface of the inner housing 212 by fusion or the like.

[0087] refer to Figures 2 to 6 , Figure 10 and Figure 11 The buffer member 217 may include a first buffer member 2171.

[0088] The first buffer member 2171 can be engaged with the inner housing 212 to block the entire surface of the first gas outlet 216 between the first gas outlet 216 and the hollow fiber membrane 211. Therefore, even if the hollow fiber membrane 211 vibrates while humid or dry gas is discharged through the first gas outlet 216, the hollow fiber membrane 211 can collide with the first buffer member 2171 instead of directly colliding with the inner housing 212. Thus, the first buffer member 2171 can buffer the impact applied to the hollow fiber membrane 211, thereby reducing the risk of damage or breakage to the hollow fiber membrane 211.

[0089] Multiple first vent holes 2171a can be formed in the first buffer member 2171. The first vent holes 2171a can be formed through the first buffer member 2171. Therefore, even if the first buffer member 2171 blocks the entire surface of the first gas outlet 216, humid or dry gas can still be discharged smoothly through the first vent holes 2171a. Each first vent hole 2171a can be formed to a smaller size than each outflow window 216a. The first vent holes 2171a can be formed by forming multiple holes in the first buffer member 2171. When the first buffer member 2171 is manufactured using a nonwoven or mesh material, the first vent holes 2171a can be achieved through pores in the material.

[0090] refer to Figures 2 to 6 and Figures 10 to 12 The buffer member 217 may include a second buffer member 2172.

[0091] The second buffer member 2172 can be engaged with the inner housing 212 to block the entire surface of the first gas inlet 215 between the first gas inlet 215 and the hollow fiber membrane 211. Therefore, even if the hollow fiber membrane 211 vibrates while humid or dry gas is introduced through the first gas inlet 215, the hollow fiber membrane 211 can collide with the second buffer member 2172 instead of directly colliding with the inner housing 212. Thus, the second buffer member 2172 can buffer the impact applied to the hollow fiber membrane 211, thereby reducing the risk of damage or breakage to the hollow fiber membrane 211.

[0092] Multiple second vents 2172a can be formed in the second buffer member 2172. The second vents 2172a can be formed through the second buffer member 2172. Therefore, even if the second buffer member 2172 blocks the entire surface of the first gas inlet 215, humid or dry gas can be smoothly introduced through the second vents 2172a. Each second vent 2172a can be formed to a smaller size than each inflow window 215a. The second vents 2172a can be formed by forming multiple holes in the second buffer member 2172. When the second buffer member 2172 is manufactured using a nonwoven or mesh material, the second vents 2172a can be achieved through pores in the material.

[0093] exist Figure 10 Although the buffer member 217 is shown as including both the first buffer member 2171 and the second buffer member 2172, this disclosure is not limited thereto, and the buffer member 217 may include only one of the first buffer member 2171 and the second buffer member 2172. That is, the buffer member 217 may include at least one of the first buffer member 2171 and the second buffer member 2172.

[0094] refer to Figure 3 , Figure 13 and Figure 14 In the humidifier 1 for a fuel cell according to this disclosure, the distance 21D (hereinafter referred to as "first distance 21D") between the first gas inlet 215 and the first gas outlet 216 can be implemented to be greater than the distance 22D (hereinafter referred to as "second distance 22D") between the second gas inlet 222 and the second gas outlet 223. Both the first distance 21D and the second distance 22D are based on a first axial direction (X-axis direction). The first distance 21D can be the distance between the midpoint of the first gas inlet 215 and the midpoint of the first gas outlet 216 in the first axial direction (X-axis direction). The second distance 22D can be the distance between the midpoint of the second gas inlet 222 and the midpoint of the second gas outlet 223 in the first axial direction (X-axis direction).

[0095] The first distance 21D can be implemented such that it is greater than the second distance 22D in the first axial direction (X-axis direction). Therefore, the second gas inlet 222 and the first gas inlet 215 can be implemented such that they do not partially or completely overlap each other in the first axial direction (X-axis direction). Therefore, the humidifier 1 for a fuel cell according to this disclosure can be implemented such that the flow of wet or dry gas introduced into the intermediate housing 22 through the second gas inlet 22 is not directly applied to the hollow fiber membrane 211, as will be described in detail below.

[0096] First, such as Figure 13 As shown, in the implementation such that the first distance 21D in the direction of the first axis ( Figure 14 (as shown) and the second distance 22D ( Figure 14 In the comparative example shown, where the two gas inlets are approximately equal to each other, the second gas inlet 222 and the first gas inlet 215 overlap each other. Therefore, in this comparative example, the wet or dry gas introduced through the second gas inlet 222 flows to the first gas inlet 215 and is directly introduced into the inner shell 212 through the first gas inlet 215. Thus, in this comparative example, the flow of wet or dry gas is directly applied to the hollow fiber membrane 211. Figure 3 As shown in the figure), thus hollow fiber membrane 211 ( Figure 3 The risk of damage or breakage (as shown in the image) is very high.

[0097] Next, as Figure 14As shown, in an embodiment where the first distance 21D in the first axial direction is greater than the second distance 22D, the second gas inlet 222 and the first gas inlet 215 do not overlap. In this case, the second gas inlet 222 and the first gas inlet 215 can be arranged to be offset from each other in the first axial direction (X-axis direction). Therefore, in this embodiment, the humid or dry gas introduced through the second gas inlet 222 flows to a position spaced apart from the first gas inlet 215, and then is introduced into the inner shell 212 through the first gas inlet 215. Therefore, this embodiment can be implemented such that the flow of humid or dry gas is not directly applied to the hollow fiber membrane 211. Figure 3 (As shown in the diagram). Therefore, in this embodiment, compared to the comparative example, the flow of humid or dry gas applied to the hollow fiber membrane 211 can be reduced, thereby reducing the degree of vibration of the hollow fiber membrane 211 due to the flow of humid or dry gas, and thus further reducing the vibration of the hollow fiber membrane 211 (as shown in the diagram). Figure 3 The risk of damage or breakage (as shown in the figure). Therefore, in this embodiment, the lifespan of the hollow fiber membrane 211 can be further extended compared to the comparative example. Although not shown, the second gas inlet 222 and the first gas inlet 215 may only partially overlap each other.

[0098] The second gas inlet 222 can be spaced apart from each of the first gas inlet 215 and the first gas outlet 216 in the first axial direction (X-axis direction). Therefore, the second gas inlet 222 can be implemented as a whole without overlapping with each of the first gas inlet 215 and the first gas outlet 216. In this case, the second gas inlet 222 can be disposed between the first gas inlet 215 and the first gas outlet 216 in the first axial direction (X-axis direction).

[0099] The second gas outlet 223 can be spaced apart from each of the first gas inlet 215 and the first gas outlet 216 in the first axial direction (X-axis direction). In this case, the second gas inlet 222 and the second gas outlet 223 can be disposed between the first gas inlet 215 and the first gas outlet 216 in the first axial direction (X-axis direction). Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, the second gas inlet 222 and the first gas inlet 215 are configured not to overlap each other, thereby reducing damage or breakage of the hollow fiber membrane 211.

[0100] In this situation, if the first distance 21D between the first gas inlet 215 and the first gas outlet 216 in the first axial direction (X-axis direction) becomes too large, the area of ​​each of the first gas inlet 215 and the first gas outlet 216 may become smaller, thereby increasing the flow rate of wet or dry gas, and thus potentially increasing the vibration of the hollow fiber membrane 211. Taking this into consideration, the first distance 21D can be determined as a length such that the hollow fiber membrane 211 will not be damaged or broken due to vibration.

[0101] refer to Figure 3 , Figure 13 and Figure 14 The intermediate housing 22 may include a partition member 224.

[0102] The partition member 224 is configured to separate the interior of the intermediate housing 22. The partition member 224 can be disposed between the second gas inlet 222 and the second gas outlet 223 in the first axial direction (X-axis direction). Therefore, the partition member 224 can divide the interior of the intermediate housing 22 into a space connected to the second gas inlet 222 and a space connected to the second gas outlet 223. Thus, the partition member 224 can prevent humid or dry gas introduced through the second gas inlet 222 from escaping through the second gas outlet 223, thereby increasing the flow rate of humid or dry gas introduced into the first gas inlet 215.

[0103] The partition member 224 can seal the space between the outer surface of the inner housing 212 and the inner surface of the intermediate housing 22. Therefore, the partition member 224 can prevent humid or dry gas introduced through the second gas inlet 222 from flowing to the second gas outlet 223. The partition member 224 can be configured to surround the outer surface of the inner housing 212. The inner surface of the intermediate housing 22 can be configured to surround the outer surface of the partition member 224. Figure 14 The dashed line in the diagram indicates the position of the separator 224. For example... Figure 14 As shown by the dashed line, the partition member 224 can be configured to traverse the interior of the intermediate housing 22 between the outer surface of the inner housing 212 and the inner surface of the intermediate housing 22.

[0104] refer to Figure 3 , Figure 13 and Figure 14In the humidifier 1 for a fuel cell according to the present disclosure, the second gas outlet 223 and the first gas outlet 216 can be configured to face different directions. Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, the humid or dry gas discharged through the first gas outlet 216 can flow in the direction of the second gas outlet 223 and then be discharged through the second gas outlet 223. Therefore, in the humidifier 1 for a fuel cell according to the present disclosure, vibrations generated at the hollow fiber membrane 211 due to the flow of humid or dry gas discharged through the first gas outlet 216 can be reduced, thereby further reducing the risk of damage or breakage of the hollow fiber membrane 211. For example, when the first gas outlet 216 is formed on the upper surface of the inner shell 212, the second gas outlet 223 can be configured to face the side surface of the inner shell 212.

[0105] The second gas inlet 222 and the first gas inlet 215 can be configured to face different directions. Therefore, in the humidifier 1 for a fuel cell according to this disclosure, humid or dry gas introduced through the second gas inlet 222 can flow in the direction of the first gas inlet 215 and then be introduced through the first gas inlet 215. Therefore, in the humidifier 1 for a fuel cell according to this disclosure, the flow of humid or dry gas applied to the hollow fiber membrane 211 can be further reduced, thereby reducing vibrations generated at the hollow fiber membrane 211 due to the flow of humid or dry gas. Therefore, in the humidifier 1 for a fuel cell according to this disclosure, the risk of damage or breakage of the hollow fiber membrane 211 can be further reduced. For example, when the first gas inlet 215 is formed on the upper surface of the inner shell 212, the second gas inlet 222 can be configured to face the side surface of the inner shell 212.

[0106] The above disclosure is not limited to the above-described embodiments and figures, and it will be apparent to those skilled in the art that various substitutions, modifications and alterations can be made without departing from the technical concept of the disclosure.

Claims

1. A humidifier for a fuel cell, the humidifier comprising: a humidification module configured to humidify dry gas supplied from the outside using wet gas discharged from a fuel cell stack; a first cover joined to one end of the humidification module; and a second cover joined to the other end of the humidification module, wherein the humidification module comprises: an intermediate housing open at opposite ends thereof; and at least one cylinder disposed in the intermediate housing, the cylinder comprising a plurality of hollow fiber membranes, the cylinder comprises: an inner housing open at opposite ends thereof, the hollow fiber membranes being accommodated in the inner housing; and a first gas inlet and a first gas outlet formed on the inner housing to be spaced apart from each other in a first axial direction, the inner housing comprises: a first segment in which the hollow fiber membranes are accommodated; a second segment spaced apart from the first segment in a second axial direction perpendicular to the first axial direction; and a third segment located between the first segment and the second segment in the second axial direction, and the average thickness of the third segment is less than each of the average thickness of the first segment and the average thickness of the second segment.

2. The humidifier according to claim 1, wherein, The third segment is formed such that a middle portion equidistantly spaced apart from opposite ends in the second axial direction has a smaller thickness than the opposite ends.

3. The humidifier according to claim 2, wherein, The third segment is formed to have a minimum thickness at the middle portion while having a gradually increasing thickness from the middle portion to the opposite ends.

4. The humidifier according to claim 1, wherein, The first segment is formed such that the thickness gradually varies from one end connected to the third segment to the other end, and the thickness gradually increases from the one end to a point with the maximum thickness, and gradually decreases from the point with the maximum thickness to the other end.

5. The humidifier according to claim 1, wherein, The inner housing is formed to be symmetric at a middle portion equidistantly spaced apart from opposite ends in the second axial direction.

6. The humidifier according to claim 1, wherein, When the width of the inner housing in the second axial direction is defined as H and the maximum thickness of the inner housing is defined as T, the inner housing is formed in a form satisfying 0.2H<T<0.5H.

7. The humidifier according to claim 1, comprising a buffer member joined to the inner housing at at least one of a position between the first gas inlet and the hollow fiber membranes and a position between the first gas outlet and the hollow fiber membranes.

8. The humidifier according to claim 7, wherein the buffer member comprises a first buffer member joined to the inner housing to block the entire surface of the first gas outlet between the first gas outlet and the hollow fiber membranes, and the first buffer member is provided with a plurality of first vent holes configured to allow wet gas or dry gas to pass therethrough.

9. The humidifier according to claim 7 or 8, wherein the buffer member comprises a second buffer member joined to the inner housing to block the entire surface of the first gas inlet between the first gas inlet and the hollow fiber membranes, and the second buffer member is provided with a plurality of second vent holes configured to allow wet gas or dry gas to pass therethrough.

10. The humidifier according to claim 7, wherein, The buffer member is made of a nonwoven material.

11. A housing for a fuel cell humidifier, configured to humidify externally supplied dry gas using humid gas discharged from a fuel cell stack, the housing comprising: An inner shell having openings formed at its ends, wherein a plurality of hollow fiber membranes are accommodated; and A first gas inlet and a first gas outlet are formed on the inner housing to be spaced apart from each other in the direction of a first axis, wherein The inner shell includes: The first segment contains the hollow fiber membrane; The second segment is spaced apart from the first segment along a second axis direction perpendicular to the first axis direction; and The third segment is located between the first and second segments along the second axis, and The average thickness of the third segment is less than the average thickness of the first segment and the average thickness of the second segment.

12. The cylindrical body according to claim 11, wherein, The third segment is formed such that the middle portion, which is equidistant from the opposite ends in the direction of the second axis, has a smaller thickness than the opposite ends.

13. The cylindrical body according to claim 12, wherein, The third segment is formed such that it has a minimum thickness in the middle portion, while gradually increasing in thickness from the middle portion to the opposite ends.

14. The cylindrical body according to claim 11, wherein, The first segment is formed such that the thickness gradually changes from one end connected to the third segment to the other end, and the thickness gradually increases from one end to the point with the maximum thickness, and gradually decreases from the point with the maximum thickness to the other end.

15. The cylindrical body according to claim 11, wherein, The inner shell is formed symmetrically with the middle portion, which is equidistant from the opposite two ends, along the second axial direction.

16. The cylindrical body according to claim 11, wherein, When the width of the inner shell in the second axial direction is defined as H and the maximum thickness of the inner shell is defined as T, the inner shell is formed in the form that satisfies 0.2H < T < 0.5H.

17. The cylindrical body according to claim 11, comprising a buffer member that engages with the inner shell at at least one of a position between the first gas inlet and the hollow fiber membrane and a position between the first gas outlet and the hollow fiber membrane.

18. The cylindrical body according to claim 17, wherein The buffer member includes a first buffer member, which is engaged with the inner housing to block the entire surface of the first gas outlet between the first gas outlet and the hollow fiber membrane. The first buffer member is provided with a plurality of first breathing holes, configured to allow humid or dry gas to pass through.

19. The cylindrical body according to claim 17 or 18, wherein The buffer member includes a second buffer member, which is engaged with the inner housing to block the entire surface of the first gas inlet between the first gas inlet and the hollow fiber membrane. The second buffer member is provided with a plurality of second breathing holes, configured to allow humid or dry gases to pass through.

20. The cylindrical body according to claim 17, wherein, The buffer component is made of nonwoven material.

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