Humidifier

Abstract

The invention relates to a humidifier (1) for a fuel cell system having a fuel cell for humidifying dry air (TL) flowing to the fuel cell with wet air (FL) flowing out of the fuel cell. The humidifier (1) comprises a membrane stack (2) and a housing (4). The humidifier (1) further comprises two circumferential seals (13a, 13b) which are tightly clamped between the membrane stack (2) and the housing (4). Each seal (13a, 13b) is assigned to a side face (6a, 6b) of the film stack (2) for wet air (FL). The invention also relates to a fuel cell system having a fuel cell and a humidifier (1).

Description

Technical Field

[0001] The present invention relates to a humidifier for a fuel cell system having a fuel cell according to the preamble of claim 1, the fuel cell system being used for a vehicle, in particular for a vehicle driven by the fuel cell system, the humidifier being used to humidify dry air flowing to the fuel cell with humid air flowing out of the fuel cell. The present invention also relates to a fuel cell system having a fuel cell and a humidifier. Background Art

[0002] A humidifier can be used in a fuel cell system having a fuel cell. Here, the humidifier can be used to humidify dry air flowing to the fuel cell with humid air flowing out of the fuel cell. A fuel cell is usually a stack, i.e. a stack formed by stacking individual fuel cell elements on each other. A humidifier usually comprises a membrane stack having a plurality of membranes stacked at intervals in a stacking direction. Dry air and humid air can flow through the membrane stack in a cross-flow without mixing, so that moisture or water vapor can be transferred from the humid air to the dry air via the membrane. Here, the membrane stack is accommodated in a housing and sealed relative to the housing so that dry air and humid air can flow into and out of the membrane stack in the housing without mixing.

[0003] Since the air loses pressure constantly when flowing through the fuel cell system, the pressure in the dry air and the resulting pressure in the membrane stack is significantly higher than the pressure in the moist air. As a result, large forces are generated in the housing in the area where the dry air flows and between the membrane stack and the area where the moist air flows. In particular, the membrane stack can deform and, in the worst case, the bonding of the membrane can be damaged. Therefore, the membrane stack must be sufficiently stable, which involves additional manufacturing effort and additional costs. Summary of the invention

[0004] The object of the present invention is therefore to provide an improved or at least alternative embodiment for a humidifier of the type mentioned at the outset, in which the described disadvantages are overcome. The object of the present invention is also to provide a corresponding fuel cell system having such a humidifier.

[0005] According to the invention, this object is achieved by the subject matter of the independent claim. Advantageous embodiments are the subject matter of the dependent claims.

[0006] The invention is based on the general idea of ​​sealing the membrane stack relative to the housing on the wet side of the humidifier (wet-wet sealing) and thereby avoiding or at least reducing deformations of the membrane stack during operation of the humidifier.

[0007] The humidifier according to the present invention is arranged or designed for a fuel cell system of a vehicle, which has a fuel cell. The humidifier according to the present invention is particularly arranged or designed for a fuel cell system of a vehicle driven by a fuel cell system or a fuel cell of a fuel cell system. In particular, the humidifier is arranged or designed to humidify dry air flowing to the fuel cell with wet air flowing out of the fuel cell. The humidifier has a membrane stack including a plurality of flat membranes, wherein the membranes in the membrane stack are stacked spaced apart from each other in the stacking direction. The membrane stack has four sides oriented parallel to the stacking direction and two end faces oriented transversely to the stacking direction. Here, two opposite sides are arranged or designed for wet air to flow into and out of the membrane stack, and two other opposite sides are used for dry air to flow into and out of the membrane stack. The end face of the membrane stack is air-tight (Luftdicht) / airtight. In addition, the humidifier has a housing and the membrane stack is accommodated in the housing. Here, the humidifier has two surrounding seals, wherein each seal is sealed and clamped between the membrane stack and the housing. According to the invention, the seals are assigned to the sides for moist air and separate the sides for moist air from one another, from the sides for dry air and from the end faces in an airtight manner within the housing.

[0008] In the context of the present invention, the expressions "for dry air" and "in dry air" are used synonymously with the expression "dry air side". Similarly, the expressions "for humid air" and "in humid air" are used synonymously with the expression "humid air side".

[0009] In the membrane stack, the membranes are stacked one above the other in the stacking direction. The membranes can be airtight and permeable to moisture or water vapor, in particular, so that in the membrane stack, humid air and dry air do not pass through the membranes, but can exchange moisture or water vapor with each other. The membranes can be rectangular and flexible.

[0010] Wet air side channels and dry air side channels can be formed between the membranes, and they can alternate with each other in the stacking direction. Each dry air side channel and each wet air side channel can be arranged in a cross-flow manner transverse to the stacking direction and can be capable of flow-through / through-flow. For this reason, each dry air side channel can connect the sides of the dry air side of the membrane stack to each other in a manner that can conduct air and can be separated from the sides of the wet air side of the membrane stack in an air-tight manner. Correspondingly, each wet air side channel can connect the sides of the wet air side of the membrane stack to each other in a manner that can conduct air and can be separated from the sides of the dry air side of the membrane stack in an air-tight manner. Each adjacent membrane can be bonded to each other using two edge side adhesive strips and each channel between the membranes is also formed by the adhesive strips of these edge sides. A spacer or so-called spacer can be arranged between the membranes, which can be bonded to the membranes by means of the adhesive strips of the edge sides.

[0011] The membrane stack itself can be in the shape of a cube. The side faces and end faces of the membrane stack can completely form its outer surface or completely limit the membrane stack to the outside. The seals are formed circumferentially and can surround the side faces of the wet air side of the membrane stack. The seals can be elastic, for example.

[0012] During the operation of the humidifier, there is a pressure existing in the dry air or on the dry air side on the side of the dry air side, and there is a pressure existing in the wet air or on the wet air side on the side of the wet air side. In the membrane stack itself, the area of ​​dry air side pressure and the area of ​​wet air side pressure alternate with each other, and generally speaking, the combined pressure in the membrane stack roughly corresponds to the dry air side pressure. Since the air constantly loses pressure when flowing through the fuel cell system, the pressure on the dry air side is significantly higher than the pressure on the wet air side. For example, dry air can have a pressure of about 3 bar and wet air can have a pressure of about 2 bar. Therefore, in the housing of the humidifier, a pressure difference of about 1 bar can be formed between the various areas.

[0013] Each sealing part can separate the side of each wet air side from the side of each dry air side and from the end face in an air-tight manner, so that there is a dry air side pressure on the side of the dry air side and on the end face in the housing during the operation of the humidifier. Thus, there is a considerable pressure on the end face of the membrane stack inside and outside the membrane stack, and the expansion of the membrane stack in the stacking direction and on the end face can be avoided or at least significantly reduced. In other words, the force imbalance caused by the pressure difference inside and outside the membrane stack can be avoided or at least reduced. Damage to the membrane stack can be avoided. In addition, since the pressure is almost evenly distributed on the side and end face of the dry air side, the air-tight separation of the two sides of the dry air side relative to each other can be simplified. In particular, since the pressure is almost evenly distributed, there is no strong dry air flow from the side of a dry air side around the membrane stack to the side of another dry air side. Therefore, there is no need for the complicated and completely air-tight sealing of the sides of the two dry air sides relative to each other, and the consumption and cost of producing the humidifier can be reduced.

[0014] In one possible embodiment of the humidifier, the membrane stack can have two sealing plates. Here, the sealing plates can be placed sealingly against the respective membrane that is the last in the stacking direction and form the end face of the membrane stack. Thus, the sealing plates can be part of the membrane stack. The sealing plates can be formed, for example, from plastic and / or be connected to the respective membrane that is the last in the stacking direction in a material-locking manner (for example, adhesively bonded).

[0015] The membrane stack can be at least partially sealed relative to the housing at the respective sealing plates, so that during operation of the humidifier, a dry air side pressure is present in the housing on the side and end faces on the dry air side. The membrane stack can be at least partially sealed relative to the housing at the respective sealing plates and connected in an air-conducting manner via a bypass, so that during operation of the humidifier, a dry air side pressure is present in the housing on the side and end faces on the dry air side. As described above, this can avoid or at least significantly reduce expansion of the membrane stack in the stacking direction or on the end faces, and a complex and completely air-tight sealing of the two dry air side sides from each other can be avoided.

[0016] The membrane stack can have two labyrinth seals on the sealing plates, which are shaped away from the membrane. In this case, the labyrinth seals can bear sealingly against the housing and divide the housing into regions that are separated from one another in an at least partially airtight manner. Alternatively, the membrane stack can have two seals clamped between the sealing plates and the housing. In the same way, the seals can divide the housing into regions that are separated from one another in an at least partially airtight manner.

[0017] Accordingly, in the humidifier, the sides on the wet air side are separated from each other and from the sides and end faces on the dry air side by two surrounding seals. Here, the sealing of the sides on the wet air side can be completely airtight. The two sides on the dry air side can be separated in the housing by two labyrinth seals or two sealing parts. Since there is no strong flow of dry air from one side of the dry air side around the membrane stack to the other side of the dry air side due to the almost uniform pressure, the sealing of the sides on the dry air side can be only partially airtight. Therefore, the expenditure for sealing the membrane stack in the housing can be significantly reduced.

[0018] In one possible embodiment of the humidifier, the membrane stack can have two sealing frames. The sealing frames can be placed on the side of the wet air side at the edge and surround the side of the wet air side. Here, the sealing frames can be connected to the side of the wet air side in a sealing manner, and the seals can be clamped between the corresponding sealing frames and the housing. The sealing frames can be formed, for example, from plastic and / or be connected to the side of the wet air side in a material-locking manner (for example, adhesively bonded).

[0019] Here, one seal can be arranged on one seal frame, and the other seal can be arranged on the other seal frame, so that the seals are pressed onto the housing in opposite directions by the corresponding seal frames. In other words, the two seals can be arranged on the corresponding seal frames on the side facing away from the corresponding wet air side.

[0020] The housing of the humidifier can have two housing parts that are independent of each other or separated from each other, namely the first housing part and the second housing part. Then the corresponding sealing parts can be pressed onto the different housing parts of the housing by each sealing part frame. When assembling the humidifier, the membrane stack can be pushed into the first housing part (suitably in a pot shape) in the direction perpendicular to the side of the wet air side or the pushing direction. After pushing the membrane stack, a sealing part can be clamped between the first housing part and a sealing part frame. Then, the second housing part can be fastened to the first housing part, wherein the membrane stack is clamped between the two housing parts. Thus, another sealing part can be clamped between another sealing part frame and the second housing part. Here, the one sealing part is pressed onto the housing in one direction or the pushing direction and the other sealing part is pressed onto the housing in another direction or against the pushing direction by the corresponding sealing part frame.

[0021] Alternatively, one seal can be arranged on one seal frame and another seal on another seal frame so that each seal is pressed onto the housing in the same direction or push-in direction by the corresponding seal frame. In other words, the two seals can be oriented in the same direction or push-in direction on the membrane stack. The one seal can be arranged on the corresponding seal frame away from the side of the corresponding wet air side and the other seal can be arranged facing the side of the corresponding wet air side. The side of the wet air side and the seal facing it can be arranged on one side / same side of the seal frame, for example. Here, the seal can surround the membrane block and the side of the corresponding wet air side at intervals.

[0022] The housing can have two housing parts that are independent of or separated from each other, namely a first housing part and a second housing part. Here, each seal can be pressed onto the same housing part of the housing, for example, the first housing part, through a corresponding seal frame. When assembling the humidifier, the membrane stack can be pushed into the (suitably can-shaped) first housing part along the pushing direction perpendicular to the side of the wet air side. Here, the humidifier is pushed forward into the first housing part with the seal facing away from the side of the corresponding wet air side. After pushing the membrane stack, the two seals are arranged between the first housing part and the corresponding seal frame. Then the second housing part can be fastened to the first housing part, wherein the membrane stack is clamped between these housing parts. At this time, the two seals are pressed onto the first housing part along the pushing direction by the corresponding seal frame.

[0023] The present invention also relates to a fuel cell system for a vehicle, which has a fuel cell and the above-mentioned humidifier. The fuel cell system according to the present invention is particularly arranged or designed for a vehicle driven by a fuel cell system or a fuel cell of a fuel cell system. Here, the humidifier is connected to the fuel cell in an air-conducting manner and can be traversed by dry air flowing to the fuel cell and wet air flowing out of the fuel cell. Here, the side for dry air can be traversed by dry air, and, here, the side for wet air can be traversed by wet air. The fuel cell system can, for example, have a compressor connected upstream of the humidifier on the dry air side. During the operation of the fuel cell system and the humidifier, the dry air can flow directly to the humidifier after the compressor. The dry air can then be humidified in the humidifier and further flow to the fuel cell. The wet air can then flow from the fuel cell into the humidifier and humidify the dry air. Here, in the fuel cell system, the wet air flows over a longer distance than the dry air and has a lower pressure than the dry air. To avoid repetition, the above statement is quoted here.

[0024] Further important features and advantages of the invention emerge from the dependent claims, the drawings and the associated description of the figures with reference to the drawings.

[0025] It is to be understood that the features mentioned above and those yet to be explained below can be used not only in the respectively proposed combination but also in other combinations or alone, without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Preferred exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical components.

[0027] They are schematically shown

[0028] Figure 1 A cross-sectional view showing a first embodiment of the humidifier according to the present invention.

[0029] Figure 2 The illustration shows a first specific embodiment of a humidifier according to the invention, wherein a housing part is shown in perspective.

[0030] Figure 3 The illustration shows a humidifier according to a first embodiment of the invention without one housing part.

[0031] Figure 4 A cross-sectional view of a second embodiment of a humidifier according to the present invention is shown. DETAILED DESCRIPTION

[0032] Figure 1 A cross-sectional view of a first embodiment of a humidifier 1 according to the invention is shown. Figure 2 and Figure 3 Different views of a first embodiment of a humidifier 1 according to the invention are shown. The humidifier 1 is arranged or designed for a fuel cell system (not shown here) having a fuel cell, for humidifying dry air TL flowing to the fuel cell with humid air FL flowing out of the fuel cell. Here, the humidifier 1 has a membrane stack 2 and a housing 4, the membrane stack 2 having a plurality of flat membranes 3 stacked in a stacking direction ST, and the housing 4 having a first housing part 4a and a second housing part 4b. Figures 1 to 3 In FIG. 3 , only a few membranes 3 are shown for the sake of clarity. Figure 2 In the figure, the second housing part 4b can be shown in perspective, while in Figure 3 , the second housing part 4b is not shown.

[0033] The membrane stack 2 is shaped like a cube and has two side faces 5a, 5b through which dry air TL can flow and two side faces 6a, 6b through which wet air FL can flow. In addition, the membrane stack 2 has two air-tight end faces 7a and 7b. The side faces 5a and 5b on the dry air side are opposite to each other in the membrane stack 2 and are oriented parallel to the stacking direction ST. The side faces 6a and 6b on the wet air side are opposite to each other in the same way and are oriented parallel to the stacking direction ST. The end faces 7a and 7b are oriented transversely to the stacking direction ST. Here, the membrane stack 2 has two sealing plates 8a and 8b (see Figure 2 and Figure 3 ), which rests sealingly on the corresponding membrane 3 which is the last in the stacking direction ST. The sealing plates 8a and 8b are connected to the corresponding membrane 3 in a materially locked manner (e.g., adhesively bonded) and form the end faces 7a and 7b of the membrane stack 2. The labyrinth seals 9a and 9b (see Figure 2 and Figure 3 ) are integrally formed on the sealing plates 8a and 8b.

[0034] The individual membranes 3 are stacked on top of each other in the membrane stack 2 and bonded to each other so that the dry air TL flows through the membrane stack 2 from the side 5a to the side 5b, and the humid air FL flows through the membrane stack 2 from the side 6a to the side 6b, wherein the dry air TL and the humid air FL are in the form of a cross flow without mixing. The membranes 3 are permeable to moisture or water vapor and are airtight to air, so that the dry air TL and the humid air FL can exchange moisture or water vapor through the membranes 3.

[0035] An inlet 10a and an outlet 10b for dry air TL and an inlet 11a and an outlet 11b for wet air FL are formed in the housing 4. Here, the inlet 10a on the dry air side is assigned to the side 5a on the dry air side and is connected to it in an air-conducting manner, and the outlet 10b on the dry air side is assigned to the side 5b on the dry air side and is connected to it in an air-conducting manner. In addition, the inlet 11a on the wet air side is assigned to the side 6a on the wet air side and is connected to it in an air-conducting manner, and the outlet 11b on the wet air side is assigned to the side 6b on the wet air side and is connected to it in an air-conducting manner.

[0036] The membrane stack 2 also has two sealing frames 12a and 12b, which are associated with the wet air-side sides 6a and 6b. The sealing frames 12a and 12b are placed in a sealing manner on the edges of the wet air-side sides 6a and 6b and are, for example, adhesively bonded to the wet air-side sides 6a and 6b. In addition, two circumferential seals 13a and 13b of the humidifier 1 are clamped in a sealing manner between the respective sealing frames 12a and 12b and the housing 4.

[0037] In the first embodiment of the humidifier 1, each seal 13a and 13b is arranged on the corresponding seal frame 12a and 12b away from the corresponding side 6a and 6b. As a result, the two seals 13a and 13b are sealed and pressed onto different housing parts 4a and 4b by their respective seal frames 12a and 12b in opposite directions R1 and R2. Accordingly, when assembling the humidifier 1, the membrane stack 2 with the seal 13a can first be pushed into the first housing part 4a in the direction R1, and the seal 13a can thus be arranged between the seal frame 12a and the first housing part 4a. Subsequently, the second housing part 4b can be arranged on the first housing part 4a, and thus the second seal 13b can be arranged between the seal frame 12b and the second housing part 4b. Then, the first housing part 4a and the second housing part 4b can be connected to each other in a sealed manner-here via the surrounding seal 14. At the same time, each seal 13a and 13b may be sealingly clamped or pressed between the respective seal frame 12a and 12b and the respective housing part 4a and 4b.

[0038] In the humidifier 1, the wet air-side sides 6a and 6b are sealed by seals 13a and 13b relative to the housing 4. As a result, the inlet 11a and the outlet 11b are separated from the inlet 10a and the outlet 10b in an air-tight manner. The labyrinth seals 9a and 9b bear sealingly against the housing 4 and separate the inlet 10a and the outlet 10b from each other in an air-tight or at least partially air-tight manner.

[0039] During the operation of the humidifier 1, a dry air side pressure exists on the sides 5a and 5b on the dry air side, and a wet air side pressure exists on the sides 6a and 6b on the wet air side. In the membrane stack 2, the areas of dry air side pressure and the areas of wet air side pressure alternate with each other, and generally, the combined pressure in the membrane stack 2 roughly corresponds to the dry air side pressure. Since the sides 6a and 6b on the wet air side are separated from the other areas of the housing 4 by the seals 13a and 13b in an air-tight manner, the dry air side pressure exists on the sides 5a and 5b on the dry air side and on the outside of the end faces 7a and 7b. Accordingly, the combined pressure inside the membrane stack 2 and the pressure outside the membrane stack 2 are almost the same. This prevents or at least reduces the deformation or expansion of the membrane stack 2 on the end faces 7a and 7b.

[0040] Furthermore, due to the approximately equal pressure on the dry air-side side surfaces 5a, 5b and the end surfaces 7a, 7b, there is no strong flow of dry air TL around the membrane stack 2 from the dry air-side side surface 5a to the dry air-side side surface 5b, so that the labyrinth seals 13a and 13b do not have to separate the dry air-side side surfaces 5a and 5b from each other in a completely airtight manner. In other words, a bypass of the dry air TL around the membrane stack 2 can also occur via the corresponding labyrinth seals 9a and 9b. As a result, the manufacturing effort of the humidifier 1 and the cost of the humidifier 1 can be reduced.

[0041] Figure 4 A cross-sectional view of a second embodiment of a humidifier 1 according to the present invention is shown. In the second embodiment, the seal 13a is arranged on the seal frame 12a away from the side 6a of the wet air side. The seal 13b is arranged on the seal frame 12b facing the side 6b of the wet air side. In other words, the seal 13b and the side 6b are arranged on one side of the seal frame 12b. As a result, the two seals 13a and 13b are pressed onto the first housing part 4a in a sealed manner along a common direction R1 through their respective seal frames 12a and 12b. Accordingly, when assembling the humidifier 1, the membrane stack 2 with the seal 13a and the seal 13b can first be pushed into the housing part 4a in the direction R1, and the seals 13a and 13b are thus arranged between the correspondingly assigned seal frames 12a and 12b and the first housing part 4a. Then the second housing part 4b can be arranged on the first housing part 4a and connected to the second housing part 4b in a sealed manner-here via the surrounding seal 14. At the same time, the respective seal 13a and 13b can be clamped or pressed sealingly between the respective seal frame 12a and 12b and the first housing part 4a. Otherwise, the first embodiment and the second embodiment of the humidifier 1 correspond.

[0042] Reference numerals list

[0043] 1. Humidifier

[0044] 2 membrane stack

[0045] 3. Film

[0046] 4 Shell

[0047] 4a / 4b housing part

[0048] 5a / 5b Side view of dry air side

[0049] 6a / 6b side of wet air side

[0050] 7a / 7b end face

[0051] 8a / 8b sealing plate

[0052] 9a / 9b labyrinth seal

[0053] 10a / 10b Inlet / outlet on dry air side

[0054] 11a / 11b Inlet / outlet on wet air side

[0055] 12a / 12b Sealing frame

[0056] 13a / 13b sealing part

[0057] 14 Sealing part

[0058] ST stacking direction

[0059] R1 / R2 Direction

[0060] TL Dry Air

[0061] FL Wet Air

Claims

1. A humidifier (1) for a fuel cell system of a vehicle, the fuel cell system having a fuel cell, the humidifier being used to humidify dry air (TL) flowing to the fuel cell with humid air (FL) flowing out of the fuel cell, -in, The humidifier (1) comprises a membrane stack (2) composed of a plurality of flat membranes (3), wherein the membranes (3) in the membrane stack (2) are stacked at intervals from one another in a stacking direction (ST). wherein the membrane stack (2) has two side surfaces (5a, 5b) which are opposite one another and are oriented parallel to the stacking direction (ST) and which serve for the flow of dry air (TL) into and out of the membrane stack (2), wherein the membrane stack (2) has two further side surfaces (6a, 6b) which are opposite one another and are oriented parallel to the stacking direction (ST) and which serve for the flow of moist air (FL) into and out of the membrane stack (2), wherein the membrane stack (2) has two air-tight end faces (7a, 7b) oriented transversely to the stacking direction (ST), wherein the humidifier (1) has a housing (4) and the membrane stack (2) is accommodated in the housing (4), and wherein the humidifier (1) has two circumferential seals (13a, 13b) and each seal (13a, 13b) is clamped in a sealing manner between the membrane stack (2) and the housing (4), It is characterized in that The seals (13a, 13b) are assigned to the sides (6a, 6b) for moist air (FL) and separate the sides (6a, 6b) for moist air (FL) from each other and from the sides (5a, 5b) for dry air (TL) and from the end faces (7a, 7b) in an airtight manner within the housing (4).

2. The humidifier (1) according to claim 1, It is characterized in that The seals (13a, 13b) separate the sides (6a, 6b) for the moist air (FL) from the sides (5a, 5b) for the dry air (TL) and from the end faces (7a, 7b) in an airtight manner, so that during operation of the humidifier (1) in the housing (4), the pressure existing in the dry air is present on the sides (5a, 5b) for the dry air (TL) and on the end faces (7a, 7b).

3. The humidifier (1) according to claim 1 or 2, It is characterized in that The membrane stack (2) has two sealing plates (8a, 8b), wherein the sealing plates (8a, 8b) bear sealingly against the respective last membrane (3) in the stacking direction (ST) and form the end faces (7a, 7b) of the membrane stack (2).

4. The humidifier (1) according to claim 3, It is characterized in that The membrane stack (2) is at least partially sealed at the sealing plates (8a, 8b) relative to the housing (4) so ​​that, during operation of the humidifier (1), the pressure prevailing in the dry air (TL) prevails on the sides (5a, 5b) for the dry air (TL) and on the end faces (7a, 7b) within the housing (4), and / or - The membrane stack (2) is at least partially sealed relative to the housing (4) on the respective sealing plates (8a, 8b) and is connected in an air-conducting manner via a bypass, so that during operation of the humidifier (1) in the housing (4), the pressure existing in the dry air (TL) is present on the sides (5a, 5b) for the dry air (TL) and on the end faces (7a, 7b).

5. The humidifier (1) according to claim 3 or 4, It is characterized in that - the membrane stack (2) has two labyrinth seals (9a, 9b) formed on the respective sealing plates (8a, 8b) facing away from the membrane (3), wherein each labyrinth seal (9a, 9b) bears sealingly against the housing (4) and divides the housing (4) into regions which are separated from one another in an at least partially airtight manner, or The membrane stack (2) has two seals clamped between respective sealing plates (8a, 8b) and the housing (4), wherein each seal divides the housing (4) into regions which are separated from one another in an at least partially airtight manner.

6. A humidifier (1) according to any one of the preceding claims, It is characterized in that the membrane stack (2) has two sealing frames (12a, 12b) and each sealing frame (12a, 12b) rests against the edge of the side (6a, 6b) for moist air (FL) and surrounds the side for moist air, and The sealing frames (12a, 12b) are sealingly connected to the sides (6a, 6b) for moist air (FL) and the seals (13a, 13b) are clamped sealingly between the respective sealing frames (12a, 12b) and the housing (4).

7. The humidifier (1) according to claim 6, It is characterized in that One sealing part (13a) is arranged on one sealing part frame (12a) and the other sealing part (13b) is arranged on the other sealing part frame (12b), so that each sealing part (13a, 13b) is pressed onto the housing (4) in opposite directions (R1, R2) through the corresponding sealing part frames (12a, 12b).

8. The humidifier (1) according to claim 7, It is characterized in that The housing (4) has two housing parts (4a, 4b) which are independent of each other, and the respective seals (13a, 13b) are pressed onto different housing parts (4a, 4b) of the housing (4) via corresponding seal frames (12a, 12b).

9. The humidifier (1) according to claim 6, It is characterized in that One seal (13a) is arranged on one seal frame (12a) and the other seal (13b) is arranged on the other seal frame (12b), so that each seal (13a, 13b) is pressed onto the housing (4) in the same direction (R1) by the corresponding seal frames (12a, 12b).

10. The humidifier (1) according to claim 9, It is characterized in that The housing (4) has two housing parts (4a, 4b) which are independent of each other and each seal (13a, 13b) is pressed onto the same housing part (4a) of the housing (4) via a corresponding seal frame (12a, 12b).

11. A fuel cell system for a vehicle, comprising a fuel cell and a humidifier (1) according to any one of the preceding claims, -in, The humidifier (1) is connected to the fuel cell in an air-conducting manner and can be passed through by dry air (TL) flowing to the fuel cell and humid air (FL) flowing out of the fuel cell, and -in, The dry air (TL) can flow through the side surfaces (5a, 5b) for dry air (TL), and the moist air (FL) can flow through the side surfaces (6a, 6b) for moist air (FL).

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