CARTRIDGE OF FUEL CELL HUMIDIFIER, AND FUEL CELL HUMIDIFIER

Abstract

The present invention relates to a cartridge of a fuel cell humidifier, and a fuel cell humidifier, wherein the cartridge of a fuel cell humidifier for humidifying dry gas supplied from the outside by using wet gas discharged from a fuel cell stack comprises: an inner case having an opening at an end and containing a plurality of hollow fiber membranes; and a first fixing layer and a second fixing layer for fixing the respective ends of the hollow fiber membranes. The inner case comprises: a first divided case and a second divided case for accommodating the hollow fiber membranes; and a first press-fitting member for coupling the first divided case and the second divided case in a press-fit manner.

Claims

1. A humidifier for fuel cells, the humidifier comprising: a humidifying module configured to humidify dry gas supplied from outside using wet gas discharged from a fuel cell stack; a first cap coupled to one end of the humidifying module; and a second cap coupled to the other end of the humidifying module, wherein the humidifying module comprises: a mid-case open at opposite ends thereof; and at least one cartridge disposed in the mid-case, the cartridge comprising a plurality of hollow fiber membranes, the cartridge comprises: an inner case having openings formed in ends thereof, the inner case being configured to receive the hollow fiber membranes; and a first fixing layer and a second fixing layer configured to fix opposite ends of the hollow fiber membranes, and the inner case comprises: a first divided case and a second divided case configured to receive the hollow fiber membranes; and a first press-fit member configured to couple the first divided case and the second divided case to each other by press-fit.

2. The humidifier according to claim 1, wherein the first press-fit member comprises a first sliding groove formed in the first divided case and a first insertion member formed on the second divided case, and at least a part of the first insertion member is formed so as to have a larger size than the first sliding groove, whereby the at least a part of the first insertion member is press-fit while being inserted into the first sliding groove.

3. The humidifier according to claim 2, wherein the first press-fit member comprises a first protruding member protruding from an outer surface of the first divided case in an outward direction and a first catching member protruding from the first insertion member in the outward direction, the first sliding groove is formed in the first protruding member, and the first catching member is inserted into the first sliding groove and is supported by the first protruding member.

4. The humidifier according to claim 3, wherein the first press-fit member comprises a first restriction member protruding from the first protruding member in an upward-downward direction perpendicular to the outward direction, the outer surface of the first divided case and the first restriction member are disposed so as to face each other in a state in which the first sliding groove is located therebetween, and a part of the first insertion member and the first catching member are press-fit between the outer surface of the first divided case and the first restriction member.

5. The humidifier according to claim 1, wherein the first fixing layer and the second fixing layer are spaced apart from each other in a first axis direction, the inner case comprises a second press-fit member spaced apart from the first press-fit member in the first axis direction, and the first divided case and the second divided case are coupled to each other by press-fit using the first press-fit member and the second press-fit member.

6. The humidifier according to claim 5, wherein the first press-fit member is formed so as to have a larger length than the second press-fit member based on the first axis direction.

7. The humidifier according to claim 5, wherein the first press-fit member and the second press-fit member are formed so as to be different from each other in terms of at least one of shape and size.

8. A cartridge of a humidifier for fuel cells configured to humidify dry gas supplied from outside using wet gas discharged from a fuel cell stack, the cartridge comprising: an inner case having openings formed in ends thereof, the inner case being configured to receive a plurality of hollow fiber membranes; and a first fixing layer and a second fixing layer configured to fix opposite ends of the hollow fiber membranes, wherein the inner case comprises: a first divided case and a second divided case configured to receive the hollow fiber membranes; and a first press-fit member configured to couple the first divided case and the second divided case to each other by press-fit.

9. The cartridge according to claim 8, wherein the first press-fit member comprises a first sliding groove formed in the first divided case and a first insertion member formed on the second divided case, and at least a part of the first insertion member is formed so as to have a larger size than the first sliding groove, whereby the at least a part of the first insertion member is press-fit while being inserted into the first sliding groove.

10. The cartridge according to claim 9, wherein the first press-fit member comprises a first protruding member protruding from an outer surface of the first divided case in an outward direction and a first catching member protruding from the first insertion member in the outward direction, the first sliding groove is formed in the first protruding member, and the first catching member is inserted into the first sliding groove and is supported by the first protruding member.

11. The cartridge according to claim 10, wherein the first press-fit member comprises a first restriction member protruding from the first protruding member in an upward-downward direction perpendicular to the outward direction, the outer surface of the first divided case and the first restriction member are disposed so as to face each other in a state in which the first sliding groove is located therebetween, and a part of the first insertion member and the first catching member are press-fit between the outer surface of the first divided case and the first restriction member.

12. The cartridge according to claim 8, wherein the first fixing layer and the second fixing layer are spaced apart from each other in a first axis direction, the inner case comprises a second press-fit member spaced apart from the first press-fit member in the first axis direction, and the first divided case and the second divided case are coupled to each other by press-fit using the first press-fit member and the second press-fit member.

13. The cartridge according to claim 12, wherein the first press-fit member is formed so as to have a larger length than the second press-fit member based on the first axis direction.

14. The cartridge according to claim 12, wherein the first press-fit member and the second press-fit member are formed so as to be different from each other in terms of at least one of shape and size.

Description

DESCRIPTION OF DRAWINGS

[0022] FIG. 1 is a schematic exploded perspective view of a conventional humidifier for fuel cells.

[0023] FIG. 2 is a schematic exploded perspective view of a humidifier for fuel cells according to the present disclosure.

[0024] FIG. 3 is a schematic exploded sectional view showing the humidifier for fuel cells according to the present disclosure, taken along line I-I of FIG. 2.

[0025] FIG. 4 is a schematic coupled sectional view showing the humidifier for fuel cells according to the present disclosure, taken along line I-I of FIG. 2.

[0026] FIG. 5 is a schematic plan view of a cartridge of a humidifier for fuel cells according to the present disclosure.

[0027] FIG. 6 is a schematic exploded sectional view showing an inner case in the cartridge of the humidifier for fuel cells according to the present disclosure, taken along line II-II of FIG. 5.

[0028] FIG. 7 is a schematic assembled sectional view showing the inner case in the cartridge of the humidifier for fuel cells according to the present disclosure, taken along line II-II of FIG. 5.

[0029] FIG. 8 is a schematic side view of the cartridge of the humidifier for fuel cells according to the present disclosure.

[0030] FIG. 9 is a schematic plan view of the cartridge of the humidifier for fuel cells according to the present disclosure.

[0031] FIG. 10 is a schematic assembled sectional view showing the cartridge of the humidifier for fuel cells according to the present disclosure, taken along line III-III of FIG. 9.

BEST MODE

[0032] Hereinafter, an embodiment of a humidifier for fuel cells according to the present disclosure will be described in detail with reference to the accompanying drawings. A cartridge of a humidifier for fuel cells according to the present disclosure may be included in a humidifier for fuel cells according to the present disclosure, and therefore the cartridge of the humidifier for fuel cells according to the present disclosure will also be described while the embodiment of the humidifier for fuel cells according to the present disclosure is described. Meanwhile, in FIGS. 8 to 10, two parallel curved lines are omission lines. A dotted line of FIG. 8 indicates a part of each of a first potting layer and a second potting layer located in an inner case.

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

[0034] Referring to FIGS. 2 to 4, the humidifying module 2 humidifies dry gas supplied from the outside. The first cap 3 may be coupled to one end of the humidifying module 2. The second cap 4 may be coupled to the other end of the humidifying module 2. The first cap 3 may transmit dry gas to the humidifying module 2. In this case, the second cap 4 may transmit dry gas humidified by wet gas in the humidifying module 2 to the fuel cell stack. The first cap 3 may transmit wet gas to the humidifying module 2. In this case, the second cap 4 may discharge wet gas to the outside after dry gas is humidified in the humidifying module 2. The first cap 3 and the second cap 4 may be spaced apart from each other in a first axis direction (X-axis direction).

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

[0036] The cartridge 22 is coupled to the mid-case 21. The cartridge 22 may be disposed in the mid-case 21. Opposite ends of the mid-case 21 are open. In this case, a receiving hole 211 may be formed in the mid-case 21. The receiving hole 211 may be formed so as to extend through the mid-case 21 in the first axis direction (X-axis direction).

[0037] An inlet 212 and an outlet 213 may be formed in the mid-case 21. The inlet 212 may allow wet gas or dry gas to be introduced into the mid-case 21 therethrough. The outlet 213 may allow wet gas or dry gas to be discharged from the mid-case 21 therethrough. The inlet 212 and the outlet 213 may be disposed spaced apart from each other in the first axis direction (X-axis direction).

[0038] When wet gas flows through the inlet 212 and the outlet 213, the wet gas may be supplied into the cartridge 22 via the interior of the mid-case 21 through the inlet 212, and may then come into contact with outer surfaces of hollow fiber membranes 221 of the cartridge 22. During this process, moisture contained in the wet gas may be transmitted through the hollow fiber membranes 221 to humidify dry gas flowing along hollows of the hollow fiber membranes 221. The humidified dry gas may be discharged from the hollow fiber membranes 221, and may then be supplied to the fuel cell stack through the second cap 4. After humidifying the dry gas, the wet gas may be discharged from the cartridge 22, may flow along the interior of the mid-case 21, and may be discharged from the mid-case 21 through the outlet 213. The inlet 212 may be connected to the fuel cell stack such that wet gas is supplied thereto. Wet gas may be off-gas discharged from the fuel cell stack.

[0039] When dry gas flows through the inlet 212 and the outlet 213, the dry gas may be supplied into the cartridge 22 via the interior of the mid-case 21 through the inlet 212, and may then come into contact with the outer surfaces of the hollow fiber membranes 221. During this process, moisture in wet gas flowing along the hollows of the hollow fiber membranes 221 may be transmitted through the hollow fiber membranes 221 to humidify dry gas introduced into the cartridge 22. The humidified dry gas may be discharged from the cartridge 22, may flow along the interior of the mid-case 21, may be discharged from the mid-case 21 through the outlet 213, and may be supplied to the fuel cell stack. After humidifying the dry gas, the wet gas may be discharged from the hollow fiber membranes 221, and may then be discharged to the outside through the second cap 4. The first cap 3 may be connected to the fuel cell stack such that wet gas is supplied thereto.

[0040] The cartridge 22 is disposed in the mid-case 21, and includes a plurality of hollow fiber membranes 221. The hollow fiber membranes 221 may be coupled to the cartridge 22 so as to be modularized. Consequently, the hollow fiber membranes 221 may be installed in the mid-case 21 through a process of coupling the cartridge 22 to the mid-case 21. In the humidifier 1 for fuel cells according to the present disclosure, therefore, ease in installation, separation, and replacement of the hollow fiber membranes 221 may be improved.

[0041] The cartridge 22 may include an inner case 222.

[0042] The inner case 222 has openings formed in ends thereof, and the plurality of hollow fiber membranes 221 is received in the inner case. The hollow fiber membranes 221 may be disposed in the inner case 222 so as to be modularized. The hollow fiber membranes 221 may include a polymer membrane made of polysulfone resin, polyethersulfone resin, sulfonated polysulfone resin, polyvinylidene fluoride (PVDF) resin, polyacrylonitrile (PAN) resin, polyimide resin, polyamide imide resin, polyester imide resin, or a mixture of two or more thereof.

[0043] The cartridge 22 may include a first fixing layer 223. The first fixing layer 223 is configured to fix one end of each of the hollow fiber membranes 221. The first fixing layer 223 may close a corresponding one of the openings of the inner case 222. In this case, the first fixing layer 223 may be formed so as not to block the hollows of the hollow fiber membranes 221. The first fixing layer 223 may be formed by hardening a potting liquid, such as liquid polyurethane resin, through a casting process. A part of the first fixing layer 223 may be located in the inner case 222, and the remaining part of the first fixing layer may be protrude from the inner case 222. The first fixing layer 223 may fix one end of each of the hollow fiber membranes 221 to the inner case 222.

[0044] The cartridge 22 may include a second fixing layer 224. The second fixing layer 224 is configured to fix the other end of each of the hollow fiber membranes 221. The second fixing layer 224 may close a corresponding one of the openings of the inner case 222. In this case, the second fixing layer 224 may be formed so as not to block the hollows of the hollow fiber membranes 221. The second fixing layer 224 may be formed by hardening a potting liquid, such as liquid polyurethane resin, through a casting process. A part of the second fixing layer 224 may be located in the inner case 222, and the remaining part of the second fixing layer may protrude from the inner case 222. The second fixing layer 224 may fix the other end of each of the hollow fiber membranes 221 to the inner case 222. Since the second fixing layer 224 and the first fixing layer 223 may be formed so as not to block the hollows of the hollow fiber membranes 221, dry gas or wet gas supplied from the outside may be supplied to the hollows of the hollow fiber membranes 221 without being disturbed by the second fixing layer 224 and the first fixing layer 223, and may be discharged from the hollows of the hollow fiber membranes 221 without being disturbed by the second fixing layer 224 and the first fixing layer 223. The second fixing layer 224 and the first fixing layer 223 may be disposed spaced apart from each other in the first axis direction (X-axis direction).

[0045] The humidifying module 2 may include a plurality of packing members 23 and 23.

[0046] The packing members 23 and 23 form a hermetic seal between the cartridge 22 and the mid-case 21 in order to prevent direct mixing between dry gas and wet gas. The packing members 23 and 23 may be inserted between the cartridge 22 and the mid-case 21. In this case, the cartridge 22 may be inserted through through-holes 23a and 23a formed respectively in the packing members 23 and 23. The packing members 23 and 23 may be disposed respectively at opposite sides of the cartridge 22. Although not shown, resin layers may be formed respectively at the opposite sides of the cartridge 22 instead of the packing members 23 and 23. Each of the resin layers may be formed by hardening a liquid polymer, such as liquid polyurethane resin, using a casting method.

[0047] Referring to FIGS. 2 to 4, the first cap 3 is coupled to one end of the humidifying module 2. A space between the first cap 3 and the cartridge 22 may be isolated from a space between the cartridge 22 and the mid-case 21 in a hermetically sealed state by the packing member 23 or the resin layer.

[0048] Referring to FIGS. 2 to 4, the second cap 4 is coupled to the other end of the humidifying module 2. The second cap 4 may be coupled to the other end of the humidifying module 2 so as to be spaced apart from the first cap 3 in the first axis direction (X-axis direction). A space between the second cap 4 and the cartridge 22 may be isolated from the space between the cartridge 22 and the mid-case 21 in a hermetically sealed state by the packing member 23 or the resin layer.

[0049] Referring to FIGS. 2 to 7, in the humidifier 1 for fuel cells according to the present disclosure, the inner case 222 may be implemented through assembly of two or more divided cases. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to individually manufacture the divided cases by injection molding, whereby it is possible to improve ease in manufacture, compared to when the inner case 222 is manufactured by performing injection molding once. Meanwhile, the divided cases may be assembled using a sliding method. In this case, a potting liquid may flow out through the interface between the divided cases during a process of forming the first fixing layer 223 and the second fixing layer 224. In order to prevent this, the inner case 222 may be implemented as follows.

[0050] The inner case 222 may include a first divided case 2221, a second divided case 2222, and a first press-fit member 2223.

[0051] The first divided case 2221 and the second divided case 2222 are configured to receive the hollow fiber membranes 221. Each of the first divided case 2221 and the second divided case 2222 may correspond to a divided case configured to implement the inner case 222 through assembly. Hereinafter, a description will be given based on an embodiment in which the inner case 222 is implemented through assembly between the first divided case 2221 and the second divided case 2222; however, it is obvious to those skilled in the art to which the present disclosure pertains that an embodiment in which the inner case 222 is implemented through assembly of three or more divided cases can be derived therefrom.

[0052] The first divided case 2221 may be disposed so as to cover an upper side of the hollow fiber membranes 221. In this case, the second divided case 2222 may be disposed so as to cover a lower side of the hollow fiber membranes 221. The first divided case 2221 and the second divided case 2222 may cover opposite side surfaces of the hollow fiber membranes 221, respectively. The opposite side surfaces of the hollow fiber membranes 221 are based on a second axis direction (Y-axis direction), which is perpendicular to the first axis direction (X-axis direction). In this case, the interface between the first divided case 2221 and the second divided case 2222 may be disposed at the opposite side surfaces of the hollow fiber membranes 221. Although not shown, the first divided case 2221 may be disposed so as to cover the lower side of the hollow fiber membranes 221, and the second divided case 2222 may be disposed so as to cover the upper side of the hollow fiber membranes 221.

[0053] The first press-fit member 2223 is configured to couple the first divided case 2221 and the second divided case 2222 to each other by press-fit. In the humidifier 1 for fuel cells according to the present disclosure, therefore, the first divided case 2221 and the second divided case 2222 may be coupled to each other using the first press-fit member 2223, whereby it is possible to reduce the outflow amount of the potting liquid through the interface between the first divided case 2221 and the second divided case 2222. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to increase the force of fixing the opposite ends of the hollow fiber membranes 221 using the first fixing layer 223 and the second fixing layer 224 and to improve quality of the cartridge 22 therethrough. Also, in the humidifier 1 for fuel cells according to the present disclosure, it is possible to reduce the amount of the potting liquid that is introduced into the inner case 222 from the outside of the inner case 222 through the interface between the first divided case 2221 and the second divided case 2222 using the first press-fit member 2223. During a process in which the first divided case 2221 and the second divided case 2222 are coupled to each other through assembly, the first press-fit member 2223 may be interference-fit as the result of press-fit, whereby it is possible to prevent the interface between the first divided case 2221 and the second divided case 2222 from being opened, thereby preventing a gap from being generated therebetween. Based on the first axis direction (X-axis direction), the first press-fit member 2223 may be disposed such that the distance from the first fixing layer 223 is shorter than the distance from the second fixing layer 224. That is, the first press-fit member 2223 may be disposed closer to the first fixing layer 223.

[0054] The first press-fit member 2223 may include a first sliding groove 2223a (shown in FIG. 6) and a first insertion member 2223b.

[0055] The first sliding groove 2223a is formed in the first divided case 2221. The first divided case 2221 and the second divided case 2222 may be assembled by sliding through the first sliding groove 2223a. For example, in the state in which the first divided case 2221 and the second divided case 2222 are spaced apart from each other in the first axis direction (X-axis direction), at least one of the first divided case 2221 and the second divided case 2222 may be moved in a direction toward each other, whereby the first divided case and the second divided case may be assembly by sliding. The first sliding groove 2223a may be formed so as to extend in parallel to the first axis direction (X-axis direction).

[0056] The first insertion member 2223b is formed on the second divided case 2222. During a process in which the first divided case 2221 and the second divided case 2222 are assembled by sliding, the first insertion member 2223b may be inserted into the first sliding groove 2223a. At least a part of the first insertion member 2223b may be formed so as to have a larger size than the first sliding groove 2223a. As a result, the first insertion member 2223b may be press-fit while being inserted into the first sliding groove 2223a. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to increase the force of coupling between the first divided case 2221 and the second divided case 2222 through press-fit of the first insertion member 2223b. In this case, at least a part of the first insertion member 2223b being formed so as to have a larger size than the first sliding groove 2223a may be based on the sectional area thereof taken in the second axis direction (Y-axis direction). The entirety of the first insertion member 2223b may be formed so as to have a larger size than the first sliding groove 2223a.

[0057] The first insertion member 2223b may protrude from the second divided case 2222. The first insertion member 2223b may protrude from the opposite surface of the second divided case 2222 that faces the first divided case 2221 toward the first divided case 2221. When the first divided case 2221 and the second divided case 2222 are coupled to each other by the first press-fit member 2223, as shown in FIG. 7, the first insertion member 2223b may be disposed so as to overlap the first divided case 2221. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to further reduce the outflow amount and the inflow amount of the potting liquid using the structure in which the first insertion member 2223b and the first divided case 2221 overlap each other. The first insertion member 2223b and the second divided case 2222 may be integrally formed.

[0058] The first press-fit member 2223 may include a first protruding member 2223c and a first catching member 2223d.

[0059] The first protruding member 2223c is formed on the first divided case 2221. The first protruding member 2223c may protrude from an outer surface 2221a of the first divided case 2221 in an outward direction (direction indicated by arrow OD). The outer surface 2221a of the first divided case 2221 is a surface of the first divided case 2221 based on the second axis direction (Y-axis direction). The outward direction (direction indicated by arrow OD) may mean an outside direction of the first divided case 2221 based on an inner space thereof in which the hollow fiber membranes 221 are received. The outward direction (direction indicated by arrow OD) may be parallel to the second axis direction (Y-axis direction). The first protruding member 2223c and the first divided case 2221 may be integrally formed.

[0060] The first sliding groove 2223a may be formed in the first protruding member 2223c. A part of the first sliding groove 2223a may be formed through the first protruding member 2223c. A part of the first insertion member 2223b may be inserted into the part of the first sliding groove 2223a formed through the first protruding member 2223c.

[0061] The first catching member 2223d may protrude from the first insertion member 2223b in the outward direction (direction indicated by arrow OD). As a result, the first catching member 2223d may be inserted into the first sliding groove 2223a and may be supported by the first protruding member 2223c. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to further increase the force by which the interface between the first divided case 2221 and the second divided case 2222 is prevented from being opened, whereby a gap is prevented from being generated therebetween, using supporting force of the first protruding member 2223c that supports the first catching member 2223d. The first catching member 2223d and the first insertion member 2223b may generally be formed in a hook shape. The first catching member 2223d and the first insertion member 2223b may be integrally formed.

[0062] The first press-fit member 2223 may include a first restriction member 2223e.

[0063] The first restriction member 2223e protrudes from the first protruding member 2223c. The first restriction member 2223e may protrude from the first protruding member 2223c in an upward-downward direction (Z-axis direction). The upward-downward direction (Z-axis direction) is a direction perpendicular to each of the first axis direction (X-axis direction) and the second axis direction (Y-axis direction). The first restriction member 2223e may protrude from the first protruding member 2223c in a direction from the second divided case 2222 to the first divided case 2221. The first restriction member 2223e and the first protruding member 2223c may be integrally formed.

[0064] The first restriction member 2223e and the outer surface 2221a of the first divided case 2221 may be disposed so as to face each other in the state in which the first sliding groove 2223a is located therebetween. In this case, based on the second axis direction (Y-axis direction), the first sliding groove 2223a may be disposed between the first restriction member 2223e and the first divided case 2221. Consequently, a part of the first insertion member 2223b and the first catching member 2223d may be inserted into the first sliding groove 2223a, whereby the first insertion member 2223b and the first catching member 2223d may be press-fit between the first restriction member 2223e and the outer surface of the first divided case 2221. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to further increase the force of press-fitting the first insertion member 2223b and the first catching member 2223d using the first restriction member 2223e.

[0065] Based on the second axis direction (Y-axis direction), the distance between the first restriction member 2223e and the outer surface 2221a of the first divided case 2221 may be implemented so as to be less than the sum of the length of the first insertion member 2223b and the length of the first catching member 2223d. As a result, the first insertion member 2223b and the first catching member 2223d may be press-fit by the first restriction member 2223e and the outer surface 2221a of the first divided case 2221 while being inserted into the first sliding groove 2223a. In this case, a guide groove 2221b (shown in FIG. 6), into which the first insertion member 2223b is inserted, may be formed in the part of the outer surface 2221a of the first divided case 2221 that contacts the first insertion member 2223b. The guide groove 2221b may correspond to a part of the first sliding groove 2223a.

[0066] The first press-fit member 2223 described above may be disposed at each of opposite sides of the inner case 222 based on the second axis direction (Y-axis direction). Consequently, the humidifier 1 for fuel cells according to the present disclosure may be implemented so as to reduce the outflow amount and the inflow amount of the potting liquid through the interface between the first divided case 2221 and the second divided case 2222 at each of the opposite sides of the inner case 222 using the first press-fit member 2223.

[0067] Referring to FIGS. 2 to 8, the inner case 222 may include a second press-fit member 2224 (shown in FIG. 8).

[0068] The second press-fit member 2224 is configured to couple the first divided case 2221 and the second divided case 2222 to each other by press-fit. The second press-fit member 2224 may be spaced apart from the first press-fit member 2223 in the first axis direction (X-axis direction). As a result, the second press-fit member 2224 and the first press-fit member 2223 may couple the first divided case 2221 and the second divided case 2222 to each other by press-fit at different positions. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to more securely couple the first divided case 2221 and the second divided case 2222 to each other, whereby it is possible to further reduce the outflow amount and the inflow amount of the potting liquid through the interface between the first divided case 2221 and the second divided case 2222. In the humidifier 1 for fuel cells according to the present disclosure, therefore, it is possible to further increase the force of fixing the opposite ends of the hollow fiber membranes 221 using the first fixing layer 223 and the second fixing layer 224 and to further improve quality of the cartridge 22 therethrough.

[0069] Based on the first axis direction (X-axis direction), the second press-fit member 2224 may be disposed such that the distance from the second fixing layer 224 is shorter than the distance from the first fixing layer 223. That is, the second press-fit member 2224 may be disposed closer to the second fixing layer 224.

[0070] The second press-fit member 2224 may be disposed at each of the opposite sides of the inner case 222 based on the second axis direction (Y-axis direction). Consequently, the humidifier 1 for fuel cells according to the present disclosure may be implemented so as to reduce the outflow amount and the inflow amount of the potting liquid through the interface between the first divided case 2221 and the second divided case 2222 at each of the opposite sides of the inner case 222 using the second press-fit member 2224.

[0071] The second press-fit member 2224 may include a second sliding groove, a second insertion member, a second protruding member, a second catching member, and a second restriction member. The second sliding groove, the second insertion member, the second protruding member, the second catching member, and the second restriction member may be implemented so as to approximately coincide with the first sliding groove 2223a, the first insertion member 2223b, the first protruding member 2223c, the first catching member 2223d, and the first restriction member 2223e, respectively, and therefore a detailed description thereof will be omitted.

[0072] The second press-fit member 2224 and the first press-fit member 2223 may be formed so as to be different from each other in terms of at least one of shape and size. Consequently, the humidifier 1 for fuel cells according to the present disclosure is implemented so as to be capable of checking an assembly direction of the first divided case 2221 and the second divided case 2222 with the naked eye using the second press-fit member 2224 and the first press-fit member 2223. In this case, the shape of each of the second press-fit member 2224 and the first press-fit member 2223 may mean the contour of each of spaces occupied by the second press-fit member 2224 and the first press-fit member 2223. For example, when the second press-fit member 2224 is formed in the shape of a quadrangular plate, the first press-fit member 2223 may be formed in the shape of a disk. The size of each of the second press-fit member 2224 and the first press-fit member 2223 may be set based on the length of each of the second press-fit member 2224 and the first press-fit member 2223 based on at least one of the first axis direction (X-axis direction), the second axis direction (Y-axis direction), and the upward-downward direction (Z-axis direction). For example, the first press-fit member 2223 may be formed so as to have a larger length than the second press-fit member 2224 based on the first axis direction (X-axis direction), whereby the first press-fit member may be formed so as to have a different length from the second press-fit member 2224.

[0073] Referring to FIGS. 2 to 5, 9, and 10, the cartridge 22 may include a gas inlet 225 and a gas outlet 226.

[0074] The gas inlet 225 is formed in the inner case 222. The gas inlet 225 may be formed at one side 2220 of the inner case 222. Based on FIG. 10, one side 2220 of the inner case 222 may correspond to an upper surface. The gas inlet 225 may allow wet gas or dry gas to be introduced into the inner case 222 therethrough. The gas inlet 225 may be formed through the inner case 222. As shown in FIGS. 9 and 10, the gas inlet 225 may be implemented by one through-hole formed through the inner case 222. As shown in FIG. 5, the gas inlet 225 may be implemented by a plurality of through-holes formed through the inner case 222. In this case, the gas inlet 225 may include a plurality of inflow windows 225a formed through different parts of the inner case 222. The inflow windows 225a may be disposed spaced apart from each other in the first axis direction (X-axis direction) and the second axis direction (Y-axis direction) so as to form a matrix. The gas inlet 225 and the first fixing layer 223 may be spaced apart from each other in the first axis direction (X-axis direction). As a result, the gas inlet 225 and the first fixing layer 223 do not overlap each other. Consequently, it is possible to prevent the first fixing layer 223 from being damaged or broken by the pressure of wet gas or dry gas introduced through the gas inlet 225. In each of FIGS. 5 and 9, a dotted line indicates the position of one surface of the first fixing layer 223 that faces the gas inlet 225.

[0075] The gas outlet 226 is formed in the inner case 222. The gas outlet 226 may be formed at one side 2220 of the inner case 222. The gas outlet 226 may allow wet gas or dry gas to be discharged from the inner case 222 therethrough. The gas outlet 226 may be formed through the inner case 222. As shown in FIGS. 9 and 10, the gas outlet 226 may be implemented by one through-hole formed through the inner case 222. As shown in FIG. 5, the gas outlet 226 may be implemented by a plurality of through-holes formed through the inner case 222. In this case, the gas outlet 226 may include a plurality of outflow windows 226a formed through different parts of the inner case 222. The outflow windows 226a may be disposed spaced apart from each other in the first axis direction (X-axis direction) and the second axis direction (Y-axis direction) so as to form a matrix. The gas outlet 226 and the second fixing layer 224 may be spaced apart from each other in the first axis direction (X-axis direction). As a result, the gas outlet 226 and the second fixing layer 224 do not overlap each other. Consequently, it is possible to prevent the second fixing layer 224 from being damaged or broken by the pressure of wet gas or dry gas discharged through the gas outlet 226. In each of FIGS. 5 and 9, a dotted line indicates the position of one surface of the second fixing layer 224 that faces the gas outlet 226. The gas outlet 226 and the gas inlet 225 may be located between the second fixing layer 224 and the first fixing layer 223 based on the first axis direction (X-axis direction) The gas outlet 226 and the gas inlet 225 may be disposed spaced apart from each other in the first axis direction (X-axis direction).

[0076] When wet gas flows through the gas outlet 226 and the gas inlet 225, the wet gas may be supplied to a space between an inner surface of the mid-case 21 and an outer surface of the inner case 222 through the inlet 212, may be supplied into the inner case 222 through the gas inlet 225, and may come into contact with the outer surfaces of the hollow fiber membranes 221. During this process, moisture contained in the wet gas may be transmitted through the hollow fiber membranes 221 to humidify dry gas flowing along the hollows of the hollow fiber membranes 221. The humidified dry gas may be discharged from the hollow fiber membranes 221, and may then be supplied to the fuel cell stack through the second cap 4. After humidifying the dry gas, the wet gas may be discharged to the space between the outer surface of the inner case 222 and the inner surface of the mid-case 21 through the gas outlet 226, and may be discharged from the mid-case 21 through the outlet 213.

[0077] When dry gas flows through the gas outlet 226 and the gas inlet 225, the dry gas may be supplied to the space between the inner surface of the mid-case 21 and the outer surface of the inner case 222 through the inlet 212, may be supplied into the inner case 222 through the gas inlet 225, and may come into contact with the outer surface of the hollow fiber membrane bundle 22. During this process, moisture in wet gas flowing along the hollows of the hollow fiber membranes 221 may be transmitted through the hollow fiber membranes 221 to humidify the dry gas introduced into the inner case 222. The humidified dry gas may be discharged to the space between the outer surface of the inner case 222 and the inner surface of the mid-case 21 through the gas outlet 226, may be discharged from the mid-case 21 through the outlet 213, and may be supplied to the fuel cell stack. After humidifying the dry gas, the wet gas may be discharged from the hollow fiber membranes 221, and may then be discharged to the outside through the second cap 4.

[0078] The present disclosure described above is not limited to the above embodiments and the accompanying drawings, and it will be obvious to a person having ordinary skill in the art to which the present disclosure pertains that various substitutions, modifications, and alterations are possible without departing from the technical idea of the present disclosure.