Valves for fuel cell systems and fuel cell systems having said valves

Abstract

Valves for fuel cell systems and fuel cell systems having said valves. The present invention relates to valves for fuel cell systems, the valve comprising a housing defining an inner cavity, wherein the housing is provided with an intake passage for introducing fresh air, an exhaust passage for discharging exhaust air, a fuel cell stack intake pipe for connecting to a cathode intake port of a fuel cell stack, and a fuel cell stack exhaust pipe for connecting to a cathode exhaust port of a fuel cell stack, all communicating with each other through the inner cavity. The inner cavity houses a valve core rotatable about a central axis of the inner cavity under the drive of a motor. The valve core includes two valve flaps and a valve for closing the interface between the exhaust passage and the inner cavity. Viewed in a cross-section perpendicular to the central axis, the two valve flaps divide the inner cavity into two parts. The valve is designed to control the communication and blocking between the intake passage, exhaust passage, fuel cell stack intake pipe, and fuel cell stack exhaust pipe by adjusting the rotational position of the valve and the two valve flaps about the central axis, thereby placing the valve in at least four different switching states. The invention also relates to fuel cell systems having valves.

Description

Technical Field

[0001] The present invention relates to a valve for a fuel cell system and a fuel cell system having said valve. Background Technology

[0002] Fuel cells, as is well known, generate electricity and water through the chemical reaction of hydrogen, the fuel gas, with oxygen in the air. Most current fuel cells use four air valves: a pre-stack air shut-off valve, a post-stack air shut-off valve, a bypass valve, and a back pressure valve. When the fuel cell stops operating, air intake into the fuel cell stack must be stopped to ensure the stack's durability. Currently, two air shut-off valves are typically located at the inlet and outlet of the cathode, respectively. When the fuel cell starts, hydrogen is injected into the anode for purging and discharged through the cathode outlet, causing excessive hydrogen concentration in the exhaust. Therefore, a bypass valve is also installed at the cathode inlet to introduce some air from the inlet into the outlet, reducing the hydrogen concentration in the exhaust. Furthermore, a back pressure valve is also installed on the exhaust side to regulate the gas pressure within the fuel cell stack.

[0003] Therefore, the current air valves used in fuel cell systems are expensive, and the close proximity of the two air shut-off valves and one bypass valve results in limited space. Summary of the Invention

[0004] The purpose of this invention is to provide a valve for a fuel cell system that can perform the functions of the four air valves (i.e., two air shut-off valves, one bypass valve, and one back pressure valve) with a single valve. This reduces costs, solves the problem of limited space for the air shut-off valves and bypass valves, reduces installation difficulty, and also simplifies system control.

[0005] According to the present invention, the objective is achieved by a valve for a fuel cell system having the following characteristics.

[0006] The valve for a fuel cell system according to the present invention includes a housing defining an inner cavity, wherein the housing is provided with an air intake passage for inputting fresh air, a fuel cell stack air intake pipe for connecting to the cathode air intake of the fuel cell stack, a fuel cell stack exhaust pipe for connecting to the cathode exhaust of the fuel cell stack, and an exhaust passage for outputting exhaust gas, wherein the air intake passage, the fuel cell stack air intake pipe, the fuel cell stack exhaust pipe, and the exhaust passage are interconnected through the inner cavity.

[0007] A valve core is housed within the cavity, which is rotatable about the central axis of the cavity under the drive of a motor. The valve core includes a valve and two valve flaps. The valve is used to close the interface where an exhaust passage enters the cavity. For example, the valve can abut against the inner surface of the housing that defines the cavity within the axial height range of the interface, thereby closing the interface. Viewed in a cross-section perpendicular to the central axis, the two valve flaps divide the cavity into two parts. For this purpose, each valve flap extends, for example, from the bottom to the top of the cavity in height, and the two valve flaps are connected to each other without gap at one end, while extending to the inner surface of the housing at the other free end.

[0008] The valve is designed to control the connection and disconnection between the air intake channel, the exhaust channel, the battery stack air intake pipe, and the battery stack exhaust pipe by adjusting the rotational position of the valve and the two valve discs about the central axis, so as to place the valve in at least four different switching states.

[0009] For example, in a first switching state, both the intake and exhaust channels are separated from the battery stack intake and exhaust pipes by two valves. In a second switching state, a portion of the intake channel communicates with the battery stack intake pipe to form one of the two sections, and the other portion of the intake channel and the battery stack exhaust pipe communicate with the exhaust channel to form the other of the two sections, separated by two valves, and the valve does not close the interface of the exhaust channel. In a third switching state, the intake channel communicates with the battery stack intake pipe to form one of the two sections, and the exhaust channel communicates with the battery stack exhaust pipe to form the other of the two sections, separated by two valves, and the valve does not close the interface of the exhaust channel. In a fourth switching state, the intake channel communicates with the battery stack intake pipe to form one of the two sections, and the exhaust channel communicates with the battery stack exhaust pipe to form the other of the two sections, separated by two valves, and the valve partially closes the interface of the exhaust channel.

[0010] Therefore, by rotating the valve core, i.e., the valve valve and the two valve discs within the housing cavity, the air intake channel, the exhaust channel, the fuel cell stack air intake pipe, and the fuel cell stack exhaust pipe can be interconnected or blocked in pairs. This allows the valve to be switched to at least four different switching states, realizing at least four different operating states or operating modes of the fuel cell stack. In other words, this invention uses a single valve to replace the operation of a valve assembly consisting of multiple air valves, thus saving costs and simplifying installation and operation.

[0011] In one embodiment of the invention, the air intake passage, the exhaust passage, the battery stack air intake pipe, and the battery stack exhaust pipe are arranged circumferentially spaced apart from each other on the housing. In particular, they are arranged sequentially on the outer periphery of the housing in the order of air intake passage, exhaust passage, battery stack exhaust pipe, and battery stack air intake pipe, such that the air intake passage is directly adjacent to both the exhaust passage and the battery stack air intake pipe.

[0012] To enable the valve to switch to at least four switching states, this invention proposes that the distribution of the air intake channel, exhaust channel, battery stack air intake pipe, and battery stack exhaust pipe in the circumferential direction of the housing should be such that, starting from the first switching state where the first valve disc is within the circumferential angle range between the battery stack air intake pipe and the air intake channel, and the second valve disc is within the circumferential angle range between the exhaust channel and the battery stack exhaust pipe, during the rotation of the valve core in the same direction, when the second valve disc rotates toward the battery stack air intake pipe past the battery stack exhaust pipe, the first valve disc remains within the circumferential angle range between the battery stack air intake pipe and the air intake channel; during the rotation of the first valve disc toward the exhaust channel past the air intake channel, the second valve disc remains within the circumferential angle range between the battery stack exhaust pipe and the battery stack air intake pipe, while the valve is within the circumferential angle range between the air intake channel and the exhaust channel; and during the gradual closure of the interface between the exhaust channel and the inner cavity by the valve, the second valve disc remains within the circumferential angle range between the battery stack exhaust pipe and the battery stack air intake pipe.

[0013] In one embodiment of the invention, the inner cavity is in the form of a rotating body, which may be, for example, a cylinder, an annular cylinder, a drum-shaped body, or a sphere. The rotationally symmetric shape of the inner cavity makes it easy to manufacture and process.

[0014] In another embodiment of the invention, the first valve disc and the second valve disc are integrally formed. This simplifies manufacturing. Alternatively, the first and second valve discs can also be manufactured separately. The two valve discs can be designed as plates together or separately. Preferably, the cross-section of the plate can be rectangular, elliptical, wing-shaped, leaf-shaped, or segmental.

[0015] In another embodiment of the invention, the first valve disc and the second valve disc, or their radial extensions, include or pass through the central axis. Here, the first and second valve discs may be manufactured separately and then connected to a common shaft in a non-rotatable manner, such as by bonding or welding, the common shaft being rotatable about its central axis under the drive of a motor, the central axis of the common shaft coinciding with the central axis of the inner cavity. Alternatively, the first and second valve discs may be integrally formed with the common shaft.

[0016] Alternatively, the central axis may also be located outside the first and second valve discs and their radial extensions. Here, the first and second valve discs are arranged eccentrically relative to the central axis of the cavity and are connected, for example by a connector, to a shaft in a non-rotatable manner, such as by bonding or welding, which can rotate about its central axis under the drive of a motor, and whose central axis coincides with the central axis of the cavity.

[0017] In another embodiment of the invention, the first valve flap and the second valve flap are at 180°. This simplifies manufacturing. Alternatively, the first valve flap and the second valve flap may also be at an angle other than 0° and 180°. Preferably, this angle may be an obtuse angle. This allows for more flexible arrangement of the circumferential relative positions of the air intake passage, exhaust passage, battery stack air intake pipe, and battery stack exhaust pipe.

[0018] In another embodiment of the invention, the first valve disc and the second valve disc are each provided with a sealing element to seal the outer peripheries of the first valve disc and the second valve disc relative to the inner surface of the housing that defines the inner cavity. Here, the inner surface includes both the inner side surface of the housing and the inner surface of the housing that defines the bottom and top of the inner cavity. This ensures a gas-tight barrier between the corresponding blocked passages.

[0019] In another embodiment of the invention, two stop portions are provided inside the housing, and the first valve disc and the second valve disc can respectively seal against these two stop portions in a first switching state corresponding to the shutdown state of the fuel cell stack. Preferably, the stop portions extend axially from the bottom to the top of the inner cavity. This ensures that air does not circulate between the inside and outside of the fuel cell stack in the shutdown state.

[0020] The present invention also relates to a fuel cell system having a fuel cell stack and a valve as described above, wherein the fuel cell stack inlet pipe of the valve is connected to the cathode inlet of the fuel cell stack, and the fuel cell stack exhaust pipe of the valve is connected to the cathode exhaust outlet of the fuel cell stack. Attached Figure Description

[0021] The invention will now be explained in detail with reference to the accompanying drawings. In the drawings,

[0022] Figure 1 A fuel cell system according to the prior art is illustrated schematically.

[0023] Figure 2 A perspective view schematically illustrating an embodiment of a valve for a fuel cell system according to the present invention is shown.

[0024] Figure 3 Schematic illustration based on Figure 2 A three-dimensional view and a side view of the valve core.

[0025] Figure 4a and Figure 4b Schematic illustration based on Figure 2 A cross-sectional view of the valve, wherein, Figure 4a The diagram shows the valve positioned at its first extreme arrangement with the minimum included angle relative to the first valve disc. Figure 4b The valve is shown in its second extreme arrangement position with the maximum included angle relative to the first valve disc.

[0026] Figures 5a-5d It schematically shows the following based on Figure 4a The valve has four switching states.

[0027] Figure 6 A cross-sectional view of another embodiment of the valve according to the invention is shown schematically.

[0028] Figures 7a-7d Schematic illustration based on Figure 6 The valve has four switching states.

[0029] Figure 8 A cross-sectional view of another embodiment of the valve according to the invention is shown schematically.

[0030] Figures 9a-9d Schematic illustration based on Figure 8 The valve has four switching states.

[0031] Figure 10 The wing-shaped cross-sectional shape of the first and second valve discs is schematically shown. Detailed Implementation

[0032] Figure 1 A fuel cell system according to the prior art is shown, comprising a fuel cell and four air valves. The fuel cell is configured as a fuel cell stack 1, which includes a cathode (also called an air electrode or oxygen electrode), an anode (also called a fuel electrode or hydrogen electrode), and an electrolyte membrane between the cathode and the anode. On the cathode side of the fuel cell stack 1, air passing through a humidifier 3 is introduced into the fuel cell stack 1 via an air inlet 11, while exhaust gas from the fuel cell stack 1 is discharged to an exhaust pipe 4 via an exhaust outlet 12. To prevent air from entering the fuel cell stack 1, a pre-stack air shut-off valve 5 is provided in the air inlet pipe 2 between the humidifier 3 and the air inlet 11, and a post-stack air shut-off valve 6 is provided in the exhaust pipe 4. A bypass valve 7 is provided in a bypass pipe connecting the air inlet pipe 2 and the exhaust pipe 4 to directly guide a portion of the air at the air inlet 11 to the exhaust pipe 4. In addition, a back pressure valve 8 is provided in the exhaust pipe 4 to control and regulate the gas pressure within the fuel cell stack.

[0033] Figures 2 to 4a4b illustrates an exemplary embodiment of a valve 200 for a fuel cell system according to the present invention. The valve 200 has a cylindrical housing 210 surrounding a hollow, cylindrical inner cavity 211. On the outer periphery of the housing 210, spaced apart from each other, are sequentially arranged an air intake passage 225 for introducing fresh air, a fuel cell stack air intake pipe 215 for connecting to an air inlet 11 of the cathode of the fuel cell stack 1, a fuel cell stack exhaust pipe 216 for connecting to an exhaust outlet 12 of the cathode of the fuel cell stack 1, and an exhaust passage 226 for discharging exhaust gas. The air intake passage 225, the fuel cell stack air intake pipe 215, the fuel cell stack exhaust pipe 216, and the exhaust passage 226 can be selectively communicated with each other through the inner cavity 211 under the action of a valve core, which will be described below.

[0034] A valve core 230, comprising a first valve disc 231, a second valve disc 232, and a valve 233, is housed within the inner cavity 211. The first valve disc 231 and the second valve disc 232 are directly supported on a common rotating shaft 212 in a manner that prevents relative rotation, or are integrally formed with the rotating shaft 212. In this embodiment, the first valve disc 231, the second valve disc 232, and the rotating shaft 212 are located in the same plane. The valve 233 is connected to the rotating shaft 212 in a manner that prevents relative rotation, for example, by bonding or welding. The rotating shaft 212 is rotatable about its central axis 213 driven by a motor (not shown), which coincides with the central axis of the housing 210, particularly with the cylindrical inner cavity 211. Thus, when the rotating shaft 212 is driven to rotate, the first valve disc 231, the second valve disc 232, and the valve 233 also rotate within the inner cavity 211 along with the rotating shaft 212. In other words, driven by the motor, the first valve disc 231, the second valve disc 232, and the valve 233 can rotate synchronously in the same direction and at the same speed via the rotating shaft 212. Each valve disc 231, 232 extends radially from the rotating shaft 212 to the inner wall of the defining cavity 211 of the housing 210, with a length almost equal to but slightly smaller than the radius of the cavity 211, and a height almost equal to but slightly smaller than the height of the cavity 211. Thus, the valve discs 231, 232 can rotate freely about the central axis 213 within the cavity 211, and when viewed in a cross-section perpendicular to the central axis 213, the two valve discs 231, 232 together divide the cavity 211 into two relatively isolated, especially gas-sealed, halves. Furthermore, the first and second valve discs may each be equipped with a sealing element to seal the outer periphery of the first and second valve discs relative to the inner wall of the housing. The valve 233 closely fits the inner wall of the housing 210 defining the inner cavity 211 within the axial height range of the interface where the exhaust channel 226 enters the inner cavity 211, and is slightly larger than the interface, so that the valve 233 can partially or even completely block or close the interface within a defined circumferential angle.

[0035] Depend on Figure 4a and Figure 4b It can be clearly seen that the connecting rod 234 is not perpendicular to the first valve disc 231, but rather forms a certain angle α with the first valve disc 231, where the minimum value of α is α. min It is related to the value of the circumferential angle between the walls on both sides of the orifice where the intake passage 225 enters the inner cavity 211 (see...). Figure 4a ), and the maximum value of α is α max This relates to the value of the circumferential angle between the adjacent walls of the intake passage 225 and the exhaust passage 226 (see...). Figure 4b ). α is less than 180°, preferably less than 90°.

[0036] Valve 200 has at least four switching states. In the first switching state (see...) Figure 5a In this configuration, the first valve 231 is located between the intake passage 225 and the fuel cell stack intake pipe 215, while the second valve 232 is located between the exhaust passage 226 and the fuel cell stack exhaust pipe 216. Thus, the two valves 231 and 232 divide the inner cavity 211 into two mutually isolated, especially gas-sealed, halves. This isolates both the fuel cell stack intake pipe 215 and the fuel cell stack exhaust pipe 216 from the intake and exhaust passages 225 and 226, thereby preventing outside air from entering the fuel cell stack. A valve 233 is located on the intake and exhaust passage sides. This corresponds to the fuel cell stack's shutdown state. In this shutdown state, there is no airflow between the inside and outside of the stack.

[0037] Second switching state (see) Figure 5b In this configuration, the first valve 231 is positioned within the opening of the intake passage 225 into the inner cavity 211, effectively dividing the intake passage 225 into two outlets. Simultaneously, the second valve 232 is positioned between the fuel cell stack intake pipe 215 and the fuel cell stack exhaust pipe 216, and the valve 233 does not obstruct the interface between the exhaust passage 226 and the inner cavity 211. This corresponds to the bypass state of the fuel cell stack. At this time, a portion of the fresh air exiting the intake passage 225 enters the fuel cell stack intake pipe 215, while the remaining portion is directed to the exhaust passage 226, diluting the hydrogen concentration in the exhaust. The amount of bypassed air can be adjusted by changing the angle of the first valve 231.

[0038] In the third switching state (see Figure 5cIn this configuration, the first valve 231 completely extends beyond the opening of the intake passage 225 at the inner cavity 211, positioned between the intake passage 225 and the exhaust passage 226. The second valve 232 remains positioned between the fuel cell stack intake pipe 215 and the fuel cell stack exhaust pipe 216, and the valve 233 does not obstruct the interface between the exhaust passage 226 and the inner cavity 211. This corresponds to the operating state of the fuel cell stack. At this time, the intake passage 225 is connected to the fuel cell stack intake pipe 215, allowing fresh air to fully enter the fuel cell stack, while the fuel cell stack exhaust pipe 216 is connected to the exhaust passage 226, allowing exhaust gas to be fully discharged into the exhaust passage 226.

[0039] In the fourth switching state (see...) Figure 5d In this configuration, the first valve 231 remains between the intake passage 225 and the exhaust passage 226, and the second valve 232 remains between the fuel cell stack intake pipe 215 and the fuel cell stack exhaust pipe 216. However, the valve 233 partially blocks the interface between the exhaust passage 226 and the inner cavity 211, thereby increasing the exhaust pressure and consequently increasing the gas pressure within the fuel cell stack. This corresponds to the back pressure regulation state of the fuel cell stack. In this back pressure regulation state, the gas pressure within the fuel cell stack can be adjusted by regulating the angle of the valve.

[0040] Furthermore, on the inner wall of the defined cavity 211 of the valve 200 housing 210, a first stop 241 is provided between the air intake passage 225 and the battery stack air intake pipe 215, and a second stop 242 is provided between the exhaust passage 226 and the battery stack air intake pipe 216. The stops 241 and 242 extend axially from the bottom to the top of the cavity. In the first switching state of the valve 200, the first valve disc 231 is sealed against the stop 241, and the second valve disc 232 is sealed against the stop 242, thereby ensuring that no air enters the fuel cell stack. When the first valve disc 231 of the valve 200 rotates from the first stop 241 toward the second stop 242, the fuel cell stack can be sequentially switched from the shutdown state to the bypass state, the operating state, and the back pressure regulation state. Therefore, the valve 200 according to the present invention integrates the functions of four air valves in the prior art for fuel cell systems, namely, pre-stack and post-stack air shut-off valves, bypass valves and back pressure valves.

[0041] Figure 6 Another embodiment of the valve 300 for a fuel cell system according to the present invention is shown. This embodiment is similar to... Figure 4a , 4bThe difference in the embodiment is that the first valve disc 331 and the second valve disc 332 are not located in the same plane, but rather form an angle β less than 180° and greater than 0°. Preferably, this angle β > 90°. Here, each valve disc 331, 332 is directly supported on or integrally formed with a common rotation shaft 312 in a manner that prevents relative rotation. The central axis 313 of the rotation shaft 312 about which it rotates coincides with the central axis of the inner cavity 311. Each valve disc 331, 332 extends radially from the rotation shaft 312 to the inner wall of the defining cavity 311 of the housing 310. Its length is almost equal to, but slightly smaller than, the radius of the cavity 311, and its height is almost equal to, but slightly smaller than, the height of the cavity 311. This allows it to rotate freely within the cavity 311 about the central axis 313 of the rotation shaft 312. When viewed in a cross-section perpendicular to the central axis 313, the two valve discs 331, 332 together divide the cavity 311 into two relatively isolated, especially gas-tight, sections with different volumes. The valve 333 is connected to, for example, by bonding or welding to the rotation shaft 312 via a connecting rod 334 in a manner that prevents relative rotation, and serves to partially block or close the interface between the exhaust passage 326 and the cavity 311 at a defined circumferential angle.

[0042] Valve 300 has at least four switching states. By rotating the first valve disc 331 from the first stop 341 toward the second stop 342, valve 300 switches from the first valve disc 331 and the second valve disc 332 to the first switching state (corresponding to the fuel cell stack shutdown state, see [link to fuel cell stack shutdown state]). Figure 7a Starting from this point, the system sequentially enters a second switching state where the first valve 331 divides the intake passage 325 into two outlets (corresponding to the bypass state of the fuel cell stack, see...). Figure 7b The first valve disc 331 and the second valve disc 332 connect the fuel cell stack inlet pipe 315 to the inlet channel 325 and connect the fuel cell stack exhaust pipe 316 to the exhaust channel 326 in the third switching state (corresponding to the working state of the fuel cell stack, see...). Figure 7c ), and the fourth switching state in which the valve 333 partially blocks the interface between the exhaust passage 326 and the inner cavity 311 (corresponding to the back pressure regulation state of the fuel cell stack, see Figure 7d ).

[0043] Figure 8 Another embodiment of the valve 400 for a fuel cell system according to the present invention is shown. This embodiment is similar to... Figure 4a , Figure 4b , Figure 6The difference in the embodiment is that the plane formed by the two valve discs 431 and 432 does not include or pass through the rotating shaft 412. The first valve disc 431 and the second valve disc 432, which are in the same plane, are integrally formed and connected to the rotating shaft 412 in a non-rotatable manner by means of a connector, such as a rod 435, for example, by welding or bonding. Here, the valve discs 431 and 432 extend in height from the bottom to the top of the inner cavity 411 and in length from one side of the inner wall of the housing 410 to the other side, dividing the inner cavity 411 into two mutually isolated, especially gas-tight, halves with different volumes. The central axis 413 of the rotating shaft 412 about which it rotates coincides with the central axis of the inner cavity 411. The valve 433 is connected to the rotating shaft 412 in a non-rotatable manner by means of a connecting rod 434, for example, by bonding or welding, and is used to partially block or close the interface between the exhaust passage 426 and the inner cavity 411 at a defined circumferential angle.

[0044] Valve 400 has at least four switching states. By rotating the first valve disc 431 from the first stop 441 toward the second stop 442, valve 400 switches from the first valve disc 431 and the second valve disc 432 to the first switching state (corresponding to the fuel cell stack shutdown state, see [link to valve 400]) which isolates the fuel cell stack inlet pipe 415 and fuel cell stack exhaust pipe 416 from the inlet passage 425 and exhaust passage 426. Figure 9a Starting from this point, the system sequentially enters a second switching state where the first valve 431 divides the intake passage 425 into two outlets (corresponding to the bypass state of the fuel cell stack, see...). Figure 9b The first valve disc 431 and the second valve disc 432 connect the fuel cell stack inlet pipe 415 to the inlet channel 425 and connect the fuel cell stack exhaust pipe 416 to the exhaust channel 426 in the third switching state (corresponding to the working state of the fuel cell stack, see...). Figure 9c The fourth switching state, which involves the valve 433 partially blocking the interface between the exhaust passage 426 and the inner cavity 411 (corresponding to the back pressure regulation state of the fuel cell stack, see...), and the fourth switching state where the valve 433 partially blocks the interface between the exhaust passage 426 and the inner cavity 411 (corresponding to the back pressure regulation state of the fuel cell stack, see...). Figure 9d ).

[0045] Similarly, the first valve disc 431 and the second valve disc 432 may not be located in the same plane, that is, they may form an angle greater than 0° and less than 180°.

[0046] The circumferential positions of the first valve discs 231, 331, 431 and the second valve discs 232, 332, 432, the angles between the valves 233, 333, 433 and the first valve discs 231, 331, 431, and the circumferential positions of the air intake channels 225, 325, 425, the exhaust channels 226, 326, 426, the battery stack air intake pipes 215, 315, 415, and the battery stack exhaust pipes 216, 316, 416 should be coordinated with each other. Figure 4a , 4b to Figures 9a-9d It can be seen that the circumferential relative positions of the air intake channels 225, 325, 425 and the battery stack exhaust pipes 216, 316, 416 are designed such that when the second valve discs 232, 332, 432 rotate past the battery stack exhaust pipes 216, 316, 416 in the first direction—that is, the direction from the air intake channel directly to the exhaust channel without passing through the battery stack air intake pipe and the battery stack exhaust pipe—the first valve discs 231, 331, 431 remain in the battery stack air intake pipe 216, 316, 416. Within the circumferential angle range between 5, 315, 415 and the intake passages 225, 325, 425, and when the first valve discs 231, 331, 431 just reach the edge of the orifice at the entrance cavity 211, 311, 411 of the intake passages 225, 325, 425 without beginning to block the orifice, the valves 233, 333, 433 are within the circumferential angle range between the intake passages 225, 325, 425 and the exhaust passages 226, 326, 426.

[0047] The circumferential relative positions of the battery stack inlet pipes 215, 315, 415 and exhaust channels 226, 326, 426 are designed such that, during the rotation of the first valve discs 231, 331, 431 across the inlet channels 225, 325, 425 in the first direction, the second valve discs 232, 332, 432 are within the circumferential angle range between the battery stack exhaust pipes 216, 316, 416 and the battery stack inlet pipes 215, 315, 415, while the valves 233, 333, 433... While still within the circumferential angle range between the intake channels 225, 325, 425 and the exhaust channels 226, 326, 426, and while the valves 233, 333, 433 gradually close the interface between the exhaust channels 226, 326, 426 and the inner cavities 211, 311, 411 along the first direction, the second valve discs 232, 332, 432 are still within the circumferential angle range between the battery stack exhaust pipes 216, 316, 416 and the battery stack intake pipes 215, 315, 415.

[0048] In the above embodiments, the inner cavity can be not only a cylinder, but also a general rotationally symmetrical body of revolution, such as a drum-shaped cavity, a spherical cavity, an hourglass-shaped cavity, etc. Furthermore, the outer surface of the shell can also have a different shape than the inner cavity. For example, the inner cavity is a cylinder, while the outer surface of the shell is a cuboid. Four channels are provided in the shell, leading from the outer surface to the inner cavity. These channels are respectively connected to or form part of the air intake channel, the exhaust channel, the battery stack air intake pipe, and the battery stack exhaust pipe. In addition, the cross-section of the first valve flap and the second valve flap does not necessarily have to be rectangular (i.e., flat), but can also be other shapes, such as elliptical, wing-shaped, leaf-shaped, or segmental.

[0049] In the above embodiments, the motor can be configured as any suitable power motor, such as an electric motor, a hydraulic motor, a pneumatic motor, etc.

Claims

1. A valve for a fuel cell system, characterized in that, The valve includes a housing that defines an inner cavity. The housing is provided with an air intake channel for inputting fresh air, a fuel cell stack air intake pipe for connecting to the cathode air intake of the fuel cell stack, a fuel cell stack exhaust pipe for connecting to the cathode exhaust of the fuel cell stack, and an exhaust channel for outputting exhaust gas. The air intake channel, fuel cell stack air intake pipe, fuel cell stack exhaust pipe, and exhaust channel are interconnected through the inner cavity. A valve core is housed within the inner cavity, and this valve core can rotate about the central axis of the inner cavity under the drive of a motor. The valve core includes a valve and two valve discs. The valve can close the interface at which the exhaust passage enters the inner cavity. Viewed in a cross-section perpendicular to the central axis, the two valve discs divide the inner cavity into two isolated parts. The valve is designed to control the connection and disconnection between the intake passage, exhaust passage, battery stack intake pipe and battery stack exhaust pipe by adjusting the rotational position of the valve and the two valve discs about the central axis, so as to place the valve in at least four different switching states.

2. The valve according to claim 1, characterized in that, In the first switching state, both the intake and exhaust channels are separated from the battery stack intake and exhaust pipes by two valves.

3. The valve according to claim 1, characterized in that, In the second switching state, a portion of the air intake passage is connected to the battery stack air intake pipe to form one of the two parts, and the other portion of the air intake passage and the battery stack exhaust pipe are connected to the exhaust passage to form the other of the two parts. The two parts are separated by two valve flaps, and the valve does not close the interface of the exhaust passage.

4. The valve according to claim 1, characterized in that, In the third switching state, the air intake channel is connected to the battery stack air intake pipe to form one of the two parts, and the exhaust channel is connected to the battery stack exhaust pipe to form the other of the two parts. The two parts are separated by two valves, and the valve does not close the interface of the exhaust channel.

5. The valve according to claim 1, characterized in that, In the fourth switching state, the air intake passage is connected to the battery stack air intake pipe to form one of the two parts, and the exhaust passage is connected to the battery stack exhaust pipe to form the other of the two parts. The two parts are separated by two valve flaps, and the valve partially closes the interface of the exhaust passage.

6. The valve according to any one of claims 1 to 5, characterized in that, The air intake passage, exhaust passage, battery stack air intake pipe and battery stack exhaust pipe are arranged circumferentially spaced apart from each other on the casing.

7. The valve according to any one of claims 1 to 5, characterized in that, The inner cavity is in the form of a rotating body.

8. The valve according to claim 7, characterized in that, The rotating body is a cylinder, annular tube, drum-shaped body, or sphere.

9. The valve according to any one of claims 1 to 5, characterized in that, The first and second valve discs of the two valve discs are integrally formed.

10. The valve according to any one of claims 1 to 5, characterized in that, The first and second valve discs of the two valve discs are manufactured separately.

11. The valve according to claim 9, characterized in that, The two valve discs are designed as plates.

12. The valve according to claim 10, characterized in that, The first and second valve discs are designed as plates, respectively.

13. The valve according to claim 11, characterized in that, The cross-section of the plate is rectangular, elliptical, wing-shaped, leaf-shaped, or segmental.

14. The valve according to claim 12, characterized in that, The cross-section of the plate is rectangular, elliptical, wing-shaped, leaf-shaped, or segmental.

15. The valve according to any one of claims 1 to 5, characterized in that, The first valve disc or its radial extension thereof comprises the central axis, and the second valve disc or its radial extension thereof comprises the central axis.

16. The valve according to any one of claims 1 to 5, characterized in that, The central axis is located outside the first and second valve discs and their radial extensions.

17. The valve according to any one of claims 1 to 5, characterized in that, The first and second valve discs of the two valve discs are at 180°, or the first and second valve discs are at an angle that is neither 0° nor 180°.

18. The valve according to any one of claims 1 to 5, characterized in that, The first and second valve discs of the two valve discs are respectively equipped with sealing elements to seal the outer periphery of the first and second valve discs relative to the inner surface of the housing that defines the inner cavity.

19. The valve according to any one of claims 1 to 5, characterized in that, Two stop portions are provided on the inner side of the housing. The first valve disc and the second valve disc of the two valve discs can respectively seal against the two stop portions in the first switching state corresponding to the shutdown state of the fuel cell stack.

20. The valve according to claim 19, characterized in that, The stop extends axially from the bottom of the inner cavity to the top of the inner cavity.

21. A fuel cell system comprising a fuel cell stack and a valve according to any one of claims 1 to 20, wherein the stack inlet of the valve is connected to the cathode inlet of the fuel cell stack, and the stack exhaust pipe of the valve is connected to the cathode exhaust outlet of the fuel cell stack.

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