Intermediate case of humidifier for fuel cell and humidifier for fuel cell

Abstract

The present invention relates to an intermediate case of a humidifier for a fuel cell and a humidifier for a fuel cell, comprising: an intermediate body accommodating at least one cylinder including a plurality of hollow fiber membranes; a partition plate portion provided inside the intermediate main body, the partition plate portion dividing the inside of the intermediate main body into an inflow space into which a first gas flows and an outflow space from which the first gas is discharged; and a bypass hole formed through the partition plate portion, the bypass hole enabling a portion of the first gas introduced into the inflow space to bypass the cylinder and flow into the outflow space.

Description

Technical Field

[0001] The present disclosure relates to a humidifier for a fuel cell configured to supply humidified gas to the fuel cell. Background Art

[0002] Fuel cells have advantages in that, unlike conventional chemical batteries such as dry cells or storage batteries, they can continuously generate electricity as long as hydrogen and oxygen are supplied, and because there is no heat loss, the efficiency of the fuel cell is about twice as high as that of an internal combustion engine.

[0003] In addition, the fuel cell directly converts chemical energy generated by the combination of hydrogen and oxygen into electrical energy, thereby emitting a small amount of pollutants. Therefore, the fuel cell has the advantage that the fuel cell is environmentally friendly and can reduce concerns about resource depletion due to increased energy consumption.

[0004] Such fuel cells can be roughly classified into 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) based on the kind of electrolyte used.

[0005] These fuel cells are basically operated by the same principle, but they differ from each other in the type of fuel used, operating temperature, catalyst and electrolyte. Among these fuel cells, it is known that polymer electrolyte membrane fuel cell (PEMFC) is most advantageous for transportation systems and small stationary power generation equipment because the polymer electrolyte membrane fuel cell operates at a lower temperature than other fuel cells and the output density of the polymer electrolyte membrane fuel cell is high, and therefore, the polymer electrolyte membrane fuel cell can be miniaturized.

[0006] One of the most important factors for improving the performance of a polymer electrolyte membrane fuel cell (PEMFC) is to maintain the moisture content by supplying a predetermined amount of moisture or more to the polymer electrolyte membrane or proton exchange membrane (PEM) of a membrane electrode assembly (MEA). This is because if the polymer electrolyte membrane or proton exchange membrane is dry, the power generation efficiency suddenly decreases.

[0007] The following methods are used as methods for humidifying polymer electrolyte membranes or proton exchange membranes: 1) a bubbler humidification method, in which a pressure vessel is filled with water and a target gas is passed through a diffuser to supply moisture; 2) a direct injection method, in which the amount of moisture supply required for a fuel cell reaction is calculated and moisture is directly supplied to a gas flow tube through an electromagnetic valve; and 3) a membrane humidification method, in which moisture is supplied to a gas fluidized bed using a polymer separation membrane.

[0008] Among these methods, the membrane humidification method of supplying water vapor to air supplied to a polymer electrolyte membrane or a proton exchange membrane to humidify the polymer electrolyte membrane or the proton exchange membrane using a membrane configured to selectively transmit only water vapor contained in the exhaust gas has the advantage that the weight and size of the humidifier can be reduced.

[0009] When forming a module, a hollow fiber membrane having a large transmission area per unit volume is suitable for a selective permeable membrane used in a membrane humidification method. That is, when a humidifier is manufactured using a hollow fiber membrane, a high degree of integration of a hollow fiber membrane having a large contact surface area is possible, whereby a fuel cell can be sufficiently humidified even with a small capacity, inexpensive materials can be used, and moisture and heat contained in exhaust gas discharged from a fuel cell at a high temperature can be collected by the humidifier and the collected moisture and heat can be reused.

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

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

[0012] One of the covers 120 transmits air supplied from the outside to the humidification module 110 , and the other transmits air humidified by the humidification module 110 to the fuel cell stack.

[0013] The humidification module 110 includes: an intermediate shell 111 having an exhaust gas inlet 111a and an exhaust gas outlet 111b; and a plurality of hollow fiber membranes 112 in the intermediate shell 111. The opposite ends of the hollow fiber membranes 112 are potted in a fixing layer 113. Generally, each fixing layer 113 is formed by hardening a liquid polymer such as a liquid polyurethane resin using a casting method. The fixing layer 113 in which the ends of the hollow fiber membranes 112 are potted and the resin layer 114 provided between the fixing layer 113 and the intermediate shell 111 isolate the internal space of the cover 120 from the internal space of the intermediate shell 111. Similar to the fixing layer 113, each resin layer 114 is generally formed by hardening a liquid polymer such as a liquid polyurethane resin using a casting method.

[0014] Air supplied from the outside flows along the hollow of the hollow fiber membrane 112. Exhaust gas introduced into the intermediate housing 111 through the exhaust gas inlet 111a contacts the outer surface of the hollow fiber membrane 112, and is discharged from the intermediate housing 111 through the 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 transmitted through the hollow fiber membrane 112 to humidify the air flowing along the hollow of the hollow fiber membrane 112.

[0015] In this case, generally, when the exhaust gas is introduced into the intermediate housing 111 and then discharged from the intermediate housing 111, the housing pressure difference corresponding to the internal pressure of the intermediate housing 111 may increase. This increase in housing pressure difference may cause a decrease in efficiency of the fuel cell system, such as an increase in power consumption. The miniaturization of the humidifier for the fuel cell exacerbates this problem. Summary of the invention

[0016] Technical issues

[0017] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide an intermediate housing of a humidifier for a fuel cell and a humidifier for a fuel cell that can reduce the pressure difference in the housing.

[0018] Technical Solution

[0019] In order to achieve the above-mentioned object, the present disclosure may include the following configurations.

[0020] According to the present disclosure, an intermediate shell of a humidifier for a fuel cell is provided in the humidifier for a fuel cell, and the humidifier includes: a humidification module configured to humidify dry gas supplied to a fuel cell stack with moisture; a first cover connected to one end of the humidification module; and a second cover connected to the other end of the humidification module, and the intermediate shell may include: an intermediate body configured to accommodate at least one cylinder including a plurality of hollow fiber membranes; a partition portion provided in the intermediate body, the partition portion being configured to divide the interior of the intermediate body into an inflow space for introducing a first gas and an outflow space for discharging the first gas; and a bypass hole formed through the partition portion, the bypass hole being configured to enable a portion of the first gas introduced into the inflow space to bypass the cylinder through the bypass hole and flow to the outflow space.

[0021] A humidifier for a fuel cell according to the present disclosure may include: a humidification module configured to humidify dry gas supplied to a fuel cell stack with moisture; a first cover connected to one end of the humidification module; and a second cover connected to the other end of the humidification module. The humidification module may include: an intermediate shell having open opposite ends; and at least one cartridge including a plurality of hollow fiber membranes. The intermediate shell may include: an intermediate body configured to accommodate the cartridge; a partition portion disposed in the intermediate body, the partition portion configured to separate the interior of the intermediate body into an inflow space for introducing a first gas and an outflow space for discharging the first gas; and a bypass hole formed through the partition portion, the bypass hole being configured to allow a portion of the first gas introduced into the inflow space to bypass the cartridge through the bypass hole and flow to the outflow space.

[0022] Beneficial Effects

[0023] The present disclosure is implemented so that a portion of the first gas introduced into the inflow space bypasses the cylinder through the bypass hole and flows to the outflow space. Therefore, the present disclosure can reduce the shell pressure difference by using the bypass hole, thereby helping to improve the efficiency of the fuel cell system.

[0024] Even if the size of the intermediate housing is reduced, the present disclosure can prevent an excessive increase in the housing pressure difference by using the bypass hole. Therefore, the present disclosure can achieve multi-purpose application to various fields such as hydrogen electric vehicles through miniaturization. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic exploded perspective view of a conventional humidifier for a fuel cell.

[0026] Figure 2 is a schematic exploded perspective view of a humidifier for a fuel cell according to the present disclosure.

[0027] Figure 3 It is shown along Figure 2 FIG. 2 is a schematic exploded cross-sectional view of a humidifier for a fuel cell according to the present disclosure, taken along line II.

[0028] Figure 4 It is shown along Figure 2 A schematic connection cross-sectional view of a humidifier for a fuel cell according to the present disclosure, taken along line II.

[0029] Figure 5 and Figure 6 is a schematic plan view of a cylinder of a humidifier for a fuel cell according to the present disclosure.

[0030] Figure 7 1 is a schematic side cross-sectional view showing that an inflow space and an outflow space in an intermediate housing of a humidifier for a fuel cell according to the present disclosure are partially partitioned by a separator.

[0031] Figure 8 It is along Figure 7 Schematic cross-sectional view taken along line II-II.

[0032] Fig. 9 : is a schematic side sectional view showing that a bypass hole is formed in a separator portion in an intermediate housing of a humidifier for a fuel cell according to the present disclosure.

[0033] Fig.10 It is along Figure 7 A schematic cross-sectional view of an intermediate housing of a humidifier for a fuel cell according to a modification of the present disclosure, taken along line II-II.

[0034] Fig.11 It is the experimental result of measuring the humidification efficiency and the shell pressure difference by changing only the cross-sectional area of ​​the bypass hole without changing the cross-sectional area of ​​the inner partition surface. DETAILED DESCRIPTION

[0035] Hereinafter, an embodiment of a humidifier for a fuel cell according to the present disclosure will be described in detail with reference to the accompanying drawings. The intermediate housing of the humidifier for a fuel cell according to the present disclosure may be included in the humidifier for a fuel cell according to the present disclosure. Therefore, when describing the humidifier for a fuel cell according to the present disclosure, the barrel of the humidifier for a fuel cell according to the present disclosure will also be described. At the same time, Figure 7 and Fig. 9 In the figure, the hollow fiber membranes are simply shown by hatching, and the inner casing is omitted.

[0036] Reference Figures 2 to 4 According to the present disclosure, a humidifier 1 for a fuel cell is configured to humidify dry gas supplied to a fuel cell stack (not shown) using wet gas. The wet gas can be discharged from the fuel cell stack. The dry gas can be a fuel gas or air. The dry gas can be humidified by the wet gas and can be supplied to the fuel cell stack. According to the present disclosure, a humidifier 1 for a fuel cell includes: a humidification module 2 configured to humidify dry gas, a first cover 3 connected to one end of the humidification module 2, and a second cover 4 connected to the other end of the humidification module 2.

[0037] Reference Figures 2 to 4 , the humidification module 2 humidifies the dry gas. The first cover 3 can be connected to one end of the humidification module 2. The second cover 4 can be connected to the other end of the humidification module 2. The humidification module 2 can supply humidified dry gas to the fuel cell stack using the first gas and the second gas. When the first gas is dry gas, the second gas can be wet gas. In this case, the first gas can be humidified by the second gas and then can be supplied to the fuel cell stack. When the first gas is wet gas, the second gas can be dry gas. In this case, the second gas can be humidified by the first gas and then can be supplied to the fuel cell stack.

[0038] The humidification module 2 includes an intermediate housing 21 and at least one cylinder 22 .

[0039] The cylinder 22 is connected to the intermediate housing 21. The cylinder 22 may be disposed in the intermediate housing 21. The opposite ends of the intermediate housing 21 are open. In this case, a receiving hole 211 may be formed in the intermediate housing 21. The receiving hole 211 may be formed to extend through the intermediate housing 21 in the first axis direction (X axis direction). At least one cylinder 22 may be disposed in the receiving hole 211.

[0040] The intermediate housing 21 may include an intermediate body 210. The barrel 22 is accommodated in the intermediate body 210. The barrel 22 may be provided in the intermediate body 210 to be accommodated in the intermediate body 210. At least one barrel 22 may be accommodated in the intermediate body 210. A receiving hole 211 may be formed through the intermediate body 210 in a first axis direction (X axis direction).

[0041] A first gas inlet 212 and a first gas outlet 213 may be formed in the intermediate housing 21. The first gas inlet 212 may introduce a first gas into the intermediate body 210. The first gas outlet 213 may discharge the first gas from the intermediate body 210. The first gas outlet 213 and the first gas inlet 212 may each protrude from the intermediate body 210.

[0042] The barrel 22 is disposed in the intermediate housing 21. The barrel 22 includes a plurality of hollow fiber membranes 221. The hollow fiber membranes 221 can be connected to the barrel 22 for modularization. Therefore, the hollow fiber membranes 221 can be installed in the intermediate housing 21 by a process of connecting the barrel 22 to the intermediate housing 21. Therefore, 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 221 can be improved.

[0043] The barrel 22 may include an inner shell 222 .

[0044] The inner housing 222 has openings formed at opposite ends and accommodates the hollow fiber membranes 221. The hollow fiber membranes 221 may be disposed in the inner housing 222 for modularization. Each hollow fiber membrane 221 may include a polymer membrane made of a polysulfone resin, a polyethersulfone resin, a sulfonated polysulfone resin, a polyvinylidene fluoride (PVDF) resin, a polyacrylonitrile (PAN) resin, a polyimide resin, a polyamideimide resin, a polyesterimide resin, or a mixture of two or more thereof.

[0045] The cylinder 22 may include a first fixing layer 223. The first fixing layer 223 is configured to fix one end of each hollow fiber membrane 221. The first fixing layer 223 may close an opening formed in one end of the inner shell 222. In this case, the first fixing layer 223 may be formed so as not to block the hollow of the hollow fiber membrane 221. The first fixing layer 223 may be formed by hardening a liquid resin such as a liquid polyurethane resin through a casting process. A portion of the first fixing layer 223 may be located in the inner shell 222, and the remaining portion of the first fixing layer may protrude outward from the inner shell 222. The first fixing layer 223 may fix one end of each hollow fiber membrane 221 to the inner shell 222.

[0046] The cylinder 22 may include a second fixing layer 224. The second fixing layer 224 is configured to fix the other end of each hollow fiber membrane 221. The second fixing layer 224 may close an opening formed in the other end of the inner shell 222. In this case, the second fixing layer 224 may be formed so as not to block the hollow of the hollow fiber membrane 221. The second fixing layer 224 may be formed by hardening a liquid resin such as a liquid polyurethane resin through a casting process. A portion of the second fixing layer 224 may be located in the inner shell 222, and the remaining portion of the second fixing layer may protrude outward from the inner shell 222. The second fixing layer 224 may fix the other end of each hollow fiber membrane 221 to the inner shell 222. Since the second fixed layer 224 and the first fixed layer 223 are formed so as not to block the hollow of the hollow fiber membrane 221, the second gas can be supplied to the hollow of the hollow fiber membrane 221 without being obstructed by the second fixed layer 224 and the first fixed layer 223, and can be discharged from the hollow of the hollow fiber membrane 221 without being obstructed by the second fixed layer 224 and the first fixed layer 223.

[0047] Reference Figures 2 to 6 The cylinder 22 may include a second gas inlet 225 and a second gas outlet 226 .

[0048] The second gas inlet 225 is formed at the inner shell 222. The second gas inlet 225 may be formed at one side of the inner shell 222. One side of the inner shell 222 may be set to face any one side wall of the intermediate body 210. The second gas inlet 225 may introduce the first gas into the inner shell 222. The second gas inlet 225 may be formed through the inner shell 222. Figure 5 As shown in , the second gas inlet 225 can be implemented by a through hole formed through the inner shell 222. Figure 6As shown in , the second gas inlet 225 can be implemented by a plurality of through holes formed through the inner shell 222. In this case, the second gas inlet 225 may include a plurality of inflow windows 225a formed through different portions of the inner shell 222. The inflow windows 225a may be arranged spaced apart from each other in a first axis direction (X axis direction) and a second axis direction (Y axis direction) to form a matrix. The second axis direction (Y axis direction) is an axis direction perpendicular to the first axis direction (X axis direction).

[0049] The second gas outlet 226 is formed at the inner shell 222. The second gas outlet 226 may be formed at one side of the inner shell 222. The second gas outlet 226 may discharge the first gas from the inner shell 222. The second gas outlet 226 may be formed through the inner shell 222. Figure 5 As shown in , the second gas outlet 226 can be implemented by a through hole formed through the inner shell 222. Figure 6 As shown in , the second gas outlet 226 can be implemented by a plurality of through holes formed through the inner shell 222. In this case, the second gas outlet 226 may include a plurality of outflow windows 226a formed through different portions of the inner shell 222. The outflow windows 226a may be arranged spaced apart from each other in the first axis direction (X axis direction) and the second axis direction (Y axis direction) to form a matrix. The second gas outlet 226 and the second gas inlet 225 may be arranged spaced apart from each other in the first axis direction (X axis direction).

[0050] When the first gas is a wet gas, the first gas may be supplied to the space between the inner surface of the intermediate housing 21 and the outer surface of the cylinder 22 through the first gas inlet 212, may be supplied to the cylinder 22 through the second gas inlet 225, and may contact the outer surface of the hollow fiber membrane 221. In this process, the moisture contained in the first gas may be transmitted through the hollow fiber membrane 221 to humidify the second gas flowing along the hollow of the hollow fiber membrane 221. The humidified second gas may be discharged from the hollow fiber membrane 221 and then may be supplied to the fuel cell stack through the first cover 3 or the second cover 4. After humidifying the second gas, the first gas may be discharged to the space between the outer surface of the cylinder 22 and the inner surface of the intermediate housing 21 through the second gas outlet 226, and may be discharged from the intermediate housing 21 through the first gas outlet 213. In this case, the first gas may be exhaust gas discharged from the fuel cell stack.

[0051] When the first gas is a dry gas, the first gas can be supplied to the space between the inner surface of the intermediate housing 21 and the outer surface of the cylinder 22 through the first gas inlet 212, can be supplied to the cylinder 22 through the second gas inlet 225, and can contact the outer surface of the hollow fiber membrane 221. In this process, the moisture contained in the second gas flowing along the hollow of the hollow fiber membrane 221 can be transmitted through the hollow fiber membrane 221 to humidify the first gas introduced into the cylinder 22. The humidified first gas can be discharged to the space between the outer surface of the cylinder 22 and the inner surface of the intermediate housing 21 through the second gas outlet 226, can be discharged from the intermediate housing 21 through the first gas outlet 213, and can be supplied to the fuel cell stack. After humidifying the first gas, the second gas can be discharged from the hollow fiber membrane 221, and then can be discharged to the outside through the first cover 3 or the second cover 4. In this case, the second gas can be the exhaust gas discharged from the fuel cell stack.

[0052] The humidifying module 2 may include a plurality of pressing members 23 and 23 ′.

[0053] The compression members 23 and 23' form an airtight seal between the cylinder 22 and the intermediate housing 21 to prevent direct mixing between the first gas and the second gas. The compression members 23 and 23' can be inserted between the cylinder 22 and the intermediate housing 21. In this case, the cylinder 22 can be inserted through first through holes 23a and 23a' formed in the compression members 23 and 23', respectively. The compression members 23 and 23' can be respectively arranged at opposite ends of the cylinder 22. Although not shown, resin layers can be formed at opposite ends of the cylinder 22 to replace the compression members 23 and 23'. Each resin layer can be formed by hardening a liquid polymer such as a liquid polyurethane resin using a casting method.

[0054] Reference Figures 2 to 4 , the first cover 3 is connected to one end of the humidification module 2. The space between the first cover 3 and the cylinder 22 can be isolated from the space between the cylinder 22 and the intermediate shell 21 in an airtight sealed state by a pressing member 23 or a resin layer. The first cover 3 may include a first vent 31. The first vent 31 is configured to enable the second gas to flow therethrough. The first vent 31 may be in communication with the hollow fiber membrane 221. Therefore, in the process of the second gas flowing between the first cover 3 and the hollow fiber membrane 221, the second gas can be introduced or discharged through the first vent 31.

[0055] Reference Figures 2 to 4, the second cover 4 is connected to the other end of the humidification module 2. The second cover 4 can be connected to the other end of the humidification module 2 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 22 can be separated from the space between the cylinder 22 and the intermediate housing 21 by a compression member 23' or a resin layer in an airtight sealed state. The second cover 4 may include a second vent 41. The second vent 41 is configured to enable the second gas to flow through it. The second vent 41 may be connected to the hollow fiber membrane 221. Therefore, during the flow of the second gas between the second cover 4 and the hollow fiber membrane 221, the second gas can be introduced or discharged through the second vent 41. When the second gas is introduced through the second vent 41, the second gas can be discharged through the first vent 31. In this case, the second gas can exchange moisture with the first gas while sequentially passing through the second cover 4, the hollow of the hollow fiber membrane 221 and the first cover 3. When the second gas is discharged through the second vent 41, the second gas can be introduced through the first vent 31. In this case, the second gas may exchange moisture with the first gas while sequentially passing through the first cover 3 , the hollow of the hollow fiber membrane 221 , and the second cover 4 .

[0056] Here, the humidifier 1 for a fuel cell according to the present disclosure may be implemented to prevent the case pressure difference corresponding to the internal pressure of the intermediate case 21 from excessively increasing while the first gas is introduced into the intermediate case 111 through the first gas inlet 212 and then discharged from the intermediate case 111 through the first gas outlet 213. To this end, the intermediate case 21 may be implemented as follows.

[0057] Reference Figures 2 to 8 , the intermediate housing 21 may include a partition portion 214 .

[0058] The partition part 214 may be disposed in the intermediate body 210. The partition part 214 may separate the interior of the intermediate body 210 into an inflow space 214a and an outflow space 214b. The inflow space 214a is a space for introducing the first gas, and may be communicated with the first gas inlet 212. In the first axial direction (X-axis direction), the inflow space 214a may be disposed between the pressing member 23 and the partition part 214. The outflow space 214b is a space for discharging the first gas, and may be communicated with the first gas outlet 213. In the first axial direction (X-axis direction), the outflow space 214b may be disposed between the partition part 214 and the pressing member 23'. The partition part 214 may be disposed between the inflow space 214a and the outflow space 214b to prevent the first gas introduced into the inflow space 214a through the first gas inlet 212 from flowing directly to the outflow space 214b without passing through the interior of the cylinder 22. Therefore, the humidifier 1 for a fuel cell according to the present disclosure can improve the humidification efficiency by increasing the flow rate of the first gas introduced into the cylinder 22 .

[0059] The partition part 214 may be connected to the intermediate body 210 to block the inner partition surface 210a of the intermediate body 210. The inner partition surface 210a may correspond to the inner surface of the intermediate body 210 in which the partition part 214 is disposed. The inner partition surface 210a and the partition part 214 may be disposed between the first gas inlet 212 and the first gas outlet 213 in the first axis direction (X axis direction). In the first axis direction (X axis direction), the inner partition surface 210a and the partition part 214 may be disposed at points equidistantly spaced from the first gas inlet 212 and the first gas outlet 213, respectively. The partition part 214 and the intermediate body 210 may be integrally formed. In this case, the partition part 214 may be formed to protrude from the inner partition surface 210a toward the inside of the intermediate body 210.

[0060] Reference Figures 2 to 9 , the intermediate housing 21 may include a bypass hole 215 .

[0061] The bypass hole 215 may be formed through the separator portion 214. A portion of the first gas introduced into the inflow space 214a may bypass the barrel 22 through the bypass hole 215, and may flow to the outflow space 214b. That is, a portion of the first gas may flow directly from the inflow space 214a to the outflow space 214b without passing through the inside of the barrel 22. Therefore, the humidifier 1 for a fuel cell according to the present disclosure may achieve the following effects.

[0062] First, in the absence of the bypass hole 215, all the first gases introduced into the inflow space 214a can flow to the outflow space 214b only after passing through the interior of the cylinder 22. Therefore, when the flow rate of the first gas present in the intermediate housing 21 increases, for example, when the flow rate of the first gas introduced into the inflow space 214a increases or the flow rate of the first gas discharged from the outflow space 214b decreases, the shell pressure difference increases. The increase in the shell pressure difference may cause the efficiency of the fuel cell system to decrease, such as increased power consumption. In addition, with the miniaturization of the intermediate housing 21, the reduction in the efficiency of the fuel cell system caused by the increase in the shell pressure difference becomes more serious. Therefore, in the absence of the bypass hole 215, it is difficult to reduce the overall size.

[0063] Next, in the presence of the bypass hole 215, a portion of the first gas introduced into the inflow space 214a can bypass the barrel 22 through the bypass hole 215, and can flow to the outflow space 214b. That is, a portion of the first gas can flow directly from the inflow space 214a to the outflow space 214b through the bypass hole 215 without passing through the interior of the barrel 22. Therefore, the humidifier 1 for fuel cells according to the present disclosure can utilize the bypass hole 215 to reduce the shell pressure difference, thereby helping to improve the efficiency of the fuel cell system. In addition, even if the size of the intermediate shell 21 is reduced, the humidifier 1 for fuel cells according to the present disclosure can also utilize the bypass hole 215 to prevent the excessive increase of the shell pressure difference, thereby realizing multi-purpose applications to various fields such as hydrogen electric vehicles through miniaturization.

[0064] The bypass hole 215 may allow a portion of the first gas introduced into the inflow space 214a through the first gas inlet 212 to flow to the outflow space 214b through the bypass hole 215. The first gas introduced into the outflow space 214b through the bypass hole 215 may be discharged to the outside of the intermediate housing 21 through the first gas outlet 213. Figure 8 The bypass hole 215 is shown to be formed in a shape having a triangular cross-section, but the present disclosure is not limited thereto, and the bypass hole 215 can be formed in various shapes, for example, a shape having a polygonal cross-section such as a quadrilateral cross-section, or a shape having a circular cross-section, as long as the first gas can flow from the inflow space 214a to the outflow space 214b.

[0065] Reference Figures 2 to 10 , the bypass hole 215 may be formed through the partition portion 214 to be disposed between the upper surface 210b of the middle body 210 and the lower surface 210c of the middle body 210. At least one of the first gas inlet 212 and the first gas outlet 213 may be disposed in the upper surface 210b of the middle body 210. The lower surface 210c of the middle body 210 may be disposed opposite to the upper surface 210b of the middle body 210. The lower surface 210c of the middle body 210 may be disposed in a direction in which gravity acts.

[0066] like Fig. 9 As shown in FIG. 2 , the bypass hole 215 may be disposed at a position where a distance from an upper surface 210 b of the middle body 210 is smaller than a distance from a lower surface 210 c of the middle body 210 .

[0067] like Fig.10As shown in , the bypass hole 215 may be provided at a position where the distance from the lower surface 210c of the middle body 210 is smaller than the distance from the upper surface 210b of the middle body 210. In this case, the bypass hole 215 may discharge the condensate existing on the lower surface 210c of the middle body 210 to the outflow space 214b. The condensate may be generated by the moisture exchange between the first gas and the second gas, and may be collected on the lower surface 210c of the middle body 210 by gravity. Since the increase in the flow rate of the condensate supplied to the fuel cell stack may reduce the efficiency of the fuel cell system due to the overflow phenomenon, the humidifier 1 for the fuel cell according to the present disclosure is implemented to discharge the condensate to the outflow space 214b using the bypass hole 215, and then discharge it to the outside of the middle housing 21 through the first gas outlet 213. Thus, the humidifier 1 for the fuel cell according to the present disclosure may help improve the efficiency of the fuel cell system by discharging the condensate using the bypass hole 215.

[0068] Reference Figures 2 to 11 , the cross-sectional area of ​​the bypass hole 215 can be determined according to the cross-sectional area of ​​the inner partition surface 210a. In this case, the cross-sectional area may correspond to the area of ​​the cross section in the axial direction perpendicular to the direction in which the inflow space 214a and the outflow space 214b are spaced apart from each other. The direction in which the inflow space 214a and the outflow space 214b are spaced apart from each other may be parallel to the first axis direction (X-axis direction). The cross-sectional area may be the cross-sectional area in the second axis direction (Y-axis direction). Assuming that the cross-sectional area of ​​the inner partition surface 210a is 1, the cross-sectional area of ​​the bypass hole 215 may be implemented as 0.005 to 0.1. That is, the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a may be 0.5% to 10%. Therefore, the humidifier 1 for a fuel cell according to the present disclosure may be implemented to have a humidification efficiency and a shell pressure difference within a predetermined range, thereby contributing to improving the efficiency of the fuel cell system.

[0069] from Fig.11 It can be seen from the experimental results that when the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 0.5% to 10%, the humidifier is implemented to have a humidification efficiency and a shell pressure difference within a predetermined range. Fig.11 The experimental results are obtained by measuring the humidification efficiency and the pressure difference of the housing by changing only the cross-sectional area of ​​the bypass hole 215 without changing the cross-sectional area of ​​the inner partition surface 210a. Fig.11 Here, the cross-sectional area ratio refers to the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a.

[0070] Depend on Fig.11It can be seen that Example 1 is implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 0.5%, thereby, the humidification efficiency is 25.0RH% and the shell pressure difference is 20kPa. Example 2 is implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 1.8%, thereby, the humidification efficiency is 24.3RH% and the shell pressure difference is 18kPa. Example 3 is implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 3.6%, thereby, the humidification efficiency is 24.0RH% and the shell pressure difference is 14kPa. Example 4 is implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 10.0%, thereby, the humidification efficiency is 23.0RH% and the shell pressure difference is 10kPa. Therefore, it can be seen that embodiments 1 to 4 are implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 0.5% to 10%, whereby the humidification efficiency is 23 to 24.5RH% and the shell pressure difference is 10 to 20kPa.

[0071] In contrast, Comparative Example 1 does not have the bypass hole 215, which results in a humidification efficiency of 25.0RH% and a shell pressure difference of 30kPa, which is very high. It can be seen that in Comparative Example 1, when compared with Embodiment 1 implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 0.5%, the shell pressure difference is significantly increased even if the humidification efficiency is not significantly different. It can be seen from this that Comparative Example 1 reduces the efficiency of the fuel cell system when compared with Embodiment 1.

[0072] In addition, Comparative Example 2 was implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a was 11.0%, whereby the humidification efficiency was 22.0RH% and the shell pressure difference was 10kPa. It can be seen that in Comparative Example 2, when compared with Example 4 implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a was 10.0%, even if there was no difference in the shell pressure difference, the humidification efficiency was reduced by 1.0RH%. It can be seen that when compared with Example 4, Comparative Example 2 only reduced the humidification efficiency, thereby reducing the performance of the fuel cell system.

[0073] Therefore, it can be seen that the humidifier 1 for a fuel cell according to the present disclosure is implemented so that the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a is 0.5% to 10%, the humidification efficiency is 23 to 24.5RH%, and the shell pressure difference is 10 to 20kPa. Therefore, the humidifier 1 for a fuel cell according to the present disclosure can not only improve the performance of the fuel cell system by smoothly supplying humidified gas to the fuel cell stack, but also contribute to improving the efficiency of the fuel cell system by reducing the shell pressure difference.

[0074] Assuming that the cross-sectional area of ​​the inner partition surface 210a is 1, the cross-sectional area of ​​the bypass hole 215 may be implemented as 0.005 to 0.06. That is, the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a may be 0.5% to 6%. Assuming that the cross-sectional area of ​​the inner partition surface 210a is 1, the cross-sectional area of ​​the bypass hole 215 may be implemented as 0.005 to 0.04. That is, the ratio of the cross-sectional area of ​​the bypass hole 215 to the cross-sectional area of ​​the inner partition surface 210a may be 0.5% to 4%.

[0075] A plurality of bypass holes 215 may be formed in the separator portion 214. The bypass holes 215 and 215' may be formed through the separator portion 214 at positions spaced apart from each other. Therefore, the humidifier 1 for a fuel cell according to the present disclosure is implemented to bypass the first gas at different positions of the separator portion 214. In this case, assuming that the cross-sectional area of ​​the inner partition surface 210a is 1, the sum of the cross-sectional areas of the bypass holes 215 and 215' may be implemented as 0.005 to 0.1. That is, the ratio of the sum of the cross-sectional areas of the bypass holes 215 and 215' to the cross-sectional area of ​​the inner partition surface 210a may be 0.5% to 10%.

[0076] although Fig.10 The bypass holes 215 and 215' are shown to be disposed at positions where the distance from the lower surface 210c of the middle body 210 is smaller than the distance from the upper surface 210b of the middle body 210, but the present disclosure is not limited thereto, and the bypass holes 215 and 215' may be disposed at positions where the distance from the upper surface 210b of the middle body 210 is smaller than the distance from the lower surface 210c of the middle body 210. Some of the bypass holes 215 and 215' may be disposed at positions closer to the lower surface 210c of the middle body 210, and some of the bypass holes 215 and 215' may be disposed at positions closer to the upper surface 210b of the middle body 210. In addition, although Fig.10 It is shown that two bypass holes 215 and 215 ′ are formed in the diaphragm portion 214 , but the present disclosure is not limited thereto, and three or more bypass holes 215 may be formed in the diaphragm portion 214 .

[0077] Reference Figures 2 to 10 , the intermediate housing 21 may include an insertion hole 216 .

[0078] The insertion hole 216 may be formed through the partition portion 214. The barrel 22 may be inserted in the insertion hole 216. The partition portion 214 may support the barrel 22 inserted in the insertion hole 216, thereby connecting the barrel 22 to the intermediate body 210. The barrel 22 may be inserted in the insertion hole 216 by interference fit. The insertion hole 216 and the bypass hole 215 may be formed through the partition portion 214 at positions spaced apart from each other.

[0079] The intermediate housing 21 may include a plurality of insertion holes 216 . The insertion holes 216 , 216 ′, and 216 ″ may be formed through the separator portion 214 at positions spaced apart from each other. Therefore, the fuel cell humidifier 1 according to the present disclosure is implemented so that a plurality of cartridges 22 may be accommodated in the intermediate housing 21 . Figure 8 FIG. 2 shows two insertion holes 216, 216' formed in the partition portion 214, and Fig.10 2 , three insertion holes 216 , 216 ′, and 216 ″ are shown to be formed in the partition portion 214 ; however, the present disclosure is not limited thereto, and four or more insertion holes 216 may be formed in the partition portion 214 .

[0080] The present disclosure described above is not limited to the above embodiments and the accompanying drawings, and it is obvious to those skilled in the art to which the present disclosure belongs that various substitutions, modifications, and changes may be made without departing from the technical concept of the present disclosure.

Claims

1. An intermediate housing provided in a humidifier for a fuel cell, the humidifier comprising: a humidification module configured to humidify dry gas supplied to the fuel cell stack using wet gas; a first cover connected to one end of the humidification module; and a second cover connected to the other end of the humidification module, the intermediate housing comprising: an intermediate body configured to house at least one cartridge including a plurality of hollow fiber membranes; A partition portion provided in the intermediate body, the partition portion being configured to partition the interior of the intermediate body into an inflow space into which a first gas is introduced and an outflow space from which the first gas is discharged; and A bypass hole is formed through the partition portion, the bypass hole being configured to allow a portion of the first gas introduced into the inflow space to bypass the cylinder through the bypass hole and flow to the outflow space.

2. The intermediate housing according to claim 1, wherein: The intermediate housing includes an insertion hole formed through the partition portion, The cylinder is inserted into the insertion hole. The bypass hole and the insertion hole are formed through the partition plate portion at positions spaced apart from each other.

3. The intermediate housing according to claim 1, wherein: The partition plate portion is connected to the intermediate body to block an inner partition surface of the intermediate body, and assuming that a cross-sectional area of ​​the inner partition surface is 1, a cross-sectional area of ​​the bypass hole is 0.005 to 0.

1.

4. The intermediate housing according to claim 1, wherein: The bypass hole is formed in plurality in the partition portion, and The bypass holes are formed through the partition plate portion at positions spaced apart from each other.

5. The intermediate housing according to claim 4, wherein: The partition plate portion is connected to the intermediate body to block the inner partition surface of the intermediate body, Assuming that the cross-sectional area of ​​the inner partition surface is 1, the sum of the cross-sectional areas of the bypass holes is 0.005 to 0.

1.

6. The intermediate housing according to claim 1, wherein: The intermediate housing includes a first gas inlet configured to introduce the first gas into the inflow space and a first gas outlet configured to discharge the first gas from the outflow space, The bypass hole allows a portion of the first gas introduced into the inflow space through the first gas inlet to flow toward the outflow space through the bypass hole.

7. The intermediate housing according to claim 1, wherein: The bypass hole is provided at a position at a distance from a lower surface of the intermediate body that is smaller than a distance from an upper surface of the intermediate body to discharge condensate existing on the lower surface of the intermediate body to the outflow space.

8. A humidifier for a fuel cell, the humidifier comprising: a humidification module configured to humidify dry gas supplied to the fuel cell stack using wet gas; a first cover connected to one end of the humidification module; and A second cover connected to the other end of the humidification module, wherein The humidification module comprises: an intermediate housing having open opposite ends; and at least one cartridge including a plurality of hollow fiber membranes, The intermediate housing comprises: an intermediate body configured to receive the barrel; A partition portion provided in the intermediate body, the partition portion being configured to partition the interior of the intermediate body into an inflow space into which a first gas is introduced and an outflow space from which the first gas is discharged; and A bypass hole is formed through the partition portion, the bypass hole being configured to allow a portion of the first gas introduced into the inflow space to bypass the cylinder through the bypass hole and flow to the outflow space.

9. The humidifier according to claim 8, wherein: The intermediate housing includes an insertion hole formed through the partition portion, The cylinder is inserted into the insertion hole. The bypass hole and the insertion hole are formed through the partition plate portion at positions spaced apart from each other.

10. The humidifier according to claim 8, wherein: The partition plate portion is connected to the intermediate body to block an inner partition surface of the intermediate body, and assuming that a cross-sectional area of ​​the inner partition surface is 1, a cross-sectional area of ​​the bypass hole is 0.005 to 0.

1.

11. The humidifier according to claim 8, wherein: The bypass hole is formed in plurality in the partition portion, and The bypass holes are formed through the partition plate portion at positions spaced apart from each other.

12. The humidifier according to claim 11, wherein: The partition plate portion is connected to the intermediate body to block the inner partition surface of the intermediate body, Assuming that the cross-sectional area of ​​the inner partition surface is 1, the sum of the cross-sectional areas of the bypass holes is 0.005 to 0.

1.

13. The humidifier according to claim 8, wherein: The intermediate housing includes a first gas inlet configured to introduce the first gas into the inflow space and a first gas outlet configured to discharge the first gas from the outflow space, The bypass hole allows a portion of the first gas introduced into the inflow space through the first gas inlet to flow toward the outflow space through the bypass hole.

14. The humidifier according to claim 8, wherein: The bypass hole is provided at a position at a distance from a lower surface of the intermediate body that is smaller than a distance from an upper surface of the intermediate body to discharge condensate existing on the lower surface of the intermediate body to the outflow space.

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