Connection assembly and fuel cell system

Abstract

The utility model relates to a connecting assembly and a fuel cell system, the connecting assembly is connected between a cooling liquid loop of the fuel cell system with a multi-stack structure and a stack cooling liquid interface, and the connecting assembly comprises a cooling liquid inlet communicated with the cooling liquid loop of the fuel cell system and at least one cooling liquid outlet communicated with the stack cooling liquid interface; a first channel leading to the cooling liquid inlet and at least one second channel leading to the cooling liquid outlet are defined by the connecting piece; each adapter piece is matched with the connecting piece at the tail end of each second channel so as to limit a cooling liquid outlet and is connected with the electric pile cooling liquid interface, and each adapter piece is in radial sealing connection with the electric pile cooling liquid interface through a first sealing piece; and each adapter piece is in axial sealing connection with the connecting piece through a second sealing piece. According to the invention, radial sealing is converted into axial sealing, so that the requirement on part tolerance is reduced, and the risk of leakage between the connecting piece and the electric pile is reduced.

Description

Technical Field

[0001] The present application relates to a fuel cell system, and particularly to the connection between the coolant interface of each fuel cell stack in a fuel cell system including a multi-stack structure and the cooling circuit of the fuel cell system. Background Art

[0002] With the popularization of fuel cell technology, high-power fuel cell power sources are required in many occasions. However, the power provided by a single fuel cell stack is limited. Therefore, a multi-stack structure formed by combining multiple fuel cell stacks is needed. When using a fuel cell architecture with a multi-stack single system, the corresponding coolant connection component inlet and outlet interfaces will have a one-to-many layout, that is, a one-to-many connection is made between the system cooling circuit and the coolant interfaces of multiple fuel cell stacks through a connecting component with one interface at one end and multiple interfaces at the other end. To achieve the seal between each fuel cell stack and the connecting component in the multi-stack structure, the existing connecting component structure uses a radial seal design with a single body and multiple interfaces, that is, a radial seal design is adopted at all interfaces of the connecting component. However, multiple radial seals are easily affected by the cumulative tolerance during the processing and assembly of components, and it is impossible to ensure the sealing performance at the interface between the connecting component and the fuel cell stack, resulting in seal failure, leakage of the cooling medium, reduction of system efficiency, generation of safety risks and negative impacts on the environment. Therefore, measures need to be taken to improve the sealing performance of the coolant interface when there is a one-to-many interface arrangement.

[0003] Therefore, aiming at the problem that the radial sealing performance of the existing single-body multi-interface connecting component is poor, which is disadvantageous to the safety, efficiency and reliability of the fuel cell system, a connection component is needed that can improve the connection sealing performance between the coolant interface of the fuel cell stack in the multi-stack structure and the system cooling circuit, adapt to the cumulative tolerance of components in the multi-interface connecting component, has strong connection deformation ability, is simple in structure and can be mass-produced. Summary of the Utility Model

[0004] The present application aims to provide a connection component that can reliably seal and connect between the coolant interface of each fuel cell stack in the multi-stack structure of the fuel cell system and the cooling circuit of the fuel cell system, so as to improve the safety and reliability of the entire fuel cell system.

[0005] To achieve the above object, the present application provides a connection component that connects between the coolant circuit of a fuel cell system having a multi-stack structure and the stack coolant interface. The connection component includes: a coolant inlet communicating with the coolant circuit of the fuel cell system and at least one coolant outlet communicating with the stack coolant interface; a connecting member that defines a first passage leading to the coolant inlet and at least one second passage leading to the coolant outlet; and at least one adapter. Each adapter cooperates with the connecting member at the end of each second passage to define the coolant outlet and is connected to the stack coolant interface. A radial seal connection is made between each adapter and the stack coolant interface through a first seal, and an axial seal connection is made between each adapter and the connecting member through a second seal.

[0006] Optionally, the adapter has a body to be fitted with the connecting member and an adapter mounting portion extending from the body. The body is cylindrical, and a first groove extending in the circumferential direction is provided on the inner wall of the body. The first seal is installed in the first groove and partially protrudes from the inner wall of the body. When the adapter is installed on the stack coolant interface, the first seal abuts against the outer wall of the stack coolant interface.

[0007] Optionally, the adapter mounting portion has a plurality of adapter mounting holes, and the adapter is installed on the stack through bolts passing through the adapter mounting holes.

[0008] Optionally, a second groove extending in the circumferential direction is provided on the upper end surface of the body of the adapter facing the connecting member. The second seal is installed in the second groove and partially protrudes from the upper end surface. When the adapter is installed on the connecting member, the second seal abuts against the lower end surface of the connecting member facing the adapter.

[0009] Optionally, the first seal is a lip-shaped rubber seal ring.

[0010] Optionally, the second seal is an O-shaped rubber seal ring.

[0011] Optionally, the connecting member has a connecting member mounting portion near each coolant outlet. The connecting member mounting portion is installed on the stack in a state where the adapter is located between the connecting member and the stack.

[0012] Optionally, the connecting member mounting portion has a plurality of connecting member mounting holes, and the connecting member is installed on the stack through bolts passing through the connecting member mounting holes.

[0013] Optionally, the connection holes of the connection member mounting portion and the adapter mounting holes of the adapter mounting portion are configured to be aligned or misaligned.

[0014] This application also relates to a fuel cell system, which includes a multi-stack structure having a plurality of stacks, and a connection assembly as described above. The connection assembly is connected between the coolant interfaces of each stack of the multi-stack structure and the coolant circuit of the fuel cell system.

[0015] According to this application, when the adapter sleeved with the axial seal and the radial seal is sleeved on the coolant interface of the stack, on the one hand, by passing bolts through the adapter mounting holes, the lower end face of the adapter is fixed and fitted to the stack, completing the action of compressing the radial seal to achieve radial sealing; on the other hand, the lower end face of the connection member fits the upper end face of the adapter, and after compressing the axial seal therebetween through the mounting holes, it is installed and fixed on the stack to achieve axial sealing. In this way, the structure that was all radial sealing in the prior art is adjusted to adapt to radial sealing at one end of the connection assembly and axial sealing at the other end. This reduces the requirement for part tolerances when all are radial sealing, also reduces the leakage risk between the connection member and the stack, and improves the reliability of the operation of the entire system. Description of the Drawings

[0016] The above and other aspects of this application will be understood more clearly with reference to the following drawings. It should be noted that the drawings are only schematic and not drawn to scale. In the drawings:

[0017] Figure 1 A perspective view of the connection assembly according to this application is schematically shown;

[0018] Figure 2 A perspective view of the connection member in the connection assembly according to this application is schematically shown;

[0019] Figure 3 A top perspective view of the adapter in the connection assembly according to this application is schematically shown;

[0020] Figure 4 A bottom perspective view of the adapter in the connection assembly according to this application is schematically shown;

[0021] Figure 5 A cross-sectional view of the connection assembly according to this application when connected to the coolant interface of the stack is shown; and

[0022] Figure 6 A partial cross-sectional view of the connection assembly according to this application when connected to the coolant interface of the stack taken along a direction different from Figure 5 the direction shown is shown. Detailed Description of the Embodiments

[0023] The preferred embodiments of the present application will be described in detail below with reference to examples. Those skilled in the art should understand that these embodiments do not impose any limitations on the present application, and the features in each embodiment can be combined with each other. In different drawings, the same components are denoted by the same reference numerals, and for the sake of brevity, some components are omitted, but this does not mean excluding other components. It should be understood that the dimensions, proportional relationships, and the number of components in the drawings do not limit the present application.

[0024] Figure 1 A perspective view of a connection assembly according to the present application is schematically shown. Figure 2 is Figure 1 A perspective view of the connecting piece in the shown connection assembly. Figure 3 and Figure 4 are respectively Figure 1 A top perspective view and a bottom perspective view of the adapter in the shown connection assembly.

[0025] The connection assembly of the present application is used in a fuel cell system having a multi-stack structure, and connects the coolant circuit of the fuel cell system to the coolant interfaces of each stack in the multi-stack structure respectively. One end of the connection assembly is connected to the coolant circuit of the fuel cell system, and the other end is connected to a plurality of stack coolant outlets respectively, that is, a one-to-many connection of the coolant lines is performed.

[0026] As Figure 1 shown, the connection assembly according to the present application has a coolant inlet 10 communicating with the coolant circuit of the fuel cell system and a plurality of coolant outlets 20 communicating with the stack coolant interfaces. Figure 1 Two coolant outlets 20 are shown in the figure, but according to the number of stacks in the multi-stack structure included in the fuel cell system, the number of coolant outlets 20 can also be other numbers, for example, 3 or more, or it can also include only one coolant outlet 20 for a single-stack system. Hereinafter, only two coolant outlets 20 will be taken as an example for description, but this is only an example, and the present application is not limited thereto.

[0027] The connection assembly includes a connecting piece 1 connected to the coolant circuit of the fuel cell system and an adapter 2 that cooperates with the connecting piece 1 and is connected to each stack coolant interface. Figure 2 A perspective view of the connecting piece 1 is shown in the figure. Figure 3 and Figure 4 is a perspective view of the adapter 2. The connecting piece 1 has a generally tee-shaped configuration (as Figure 5The body 12 (as shown in the cross-sectional view) has a first channel 16 leading to the coolant inlet 10 and two second channels 17 leading to the coolant outlets 20. The first channel 16 and the second channels 17 are preferably circular channels. The coolant inlet 10 extends from the body 12 and is formed in the shape of a pipe joint. The connector 1 also has a connector mounting portion 15 extending from the body 12 near each coolant outlet 20, such as a flange-shaped connector mounting portion 15. There are two connector mounting portions 15 in the figure. The lower surface 11 of each said connector mounting portion 15 is used to cooperate with the adapter 2. The inner cavity of the connector mounting portion 15 defines a part of the second channel 17. Each connector mounting portion 15 is also provided with a connector mounting hole 13 for being fixed to each stack 6, for example, by bolts, as Figure 5 shown in 6 of

[0028] Figure 1 and Figure 2 As shown in, each connector mounting portion 15 is provided with two connector mounting holes 13, but the number of the connector mounting holes 13 is not limited to this and can be other numbers, which are set according to the available mounting space and requirements. The connector mounting portion 15 is not limited to the flange form either, but can be designed into other shapes according to needs. The connector mounting portion 15 is not limited to being fixed to the stack 6 by connecting through the connector mounting hole 13 and bolts as shown in the figure either, but other known methods in the art can also be used to fix the connector 1 and the stack 6, such as snap connection, etc.

[0029] As Figure 3 and 4 shown, the adapter 2 in the connection assembly according to the present application includes a main body 24 and an adapter mounting portion 25 extending from the main body 24. The main body 24 is cylindrical, and its minimum inner diameter is the same as that of the body 12 of the connector 1 and the second channel 17 in the connector mounting portion 5 to ensure smooth fluid flow. Of course, it can also be different.

[0030] A first groove 26 extending in the circumferential direction is provided on the inner wall of the main body 24 of the adapter 2 (as Figure 6 shown in

[0031] ). A first seal 4 (also called a radial seal) can be arranged in the first groove 26 and protrude beyond the inner wall of the main body 24. The first seal 4 can be an O-ring or a lip seal, depending on the type of fluid to be sealed and specific sealing requirements.

[0032] On the upper end face 22 of the main body 24 (i.e., the end face facing the connecting member 1), a second groove 27 extending in the circumferential direction is provided. The second seal 3 (which can also be referred to as an axial seal) can be disposed in the second groove 27 and protrude from the second groove 27 beyond the upper end face 22. The second seal 3 can be an O-ring seal or a seal of other shapes, not limited thereto, depending on the type of fluid to be sealed and specific sealing requirements.

[0033] The cross-section of the second groove 27 can be generally rectangular, but of course it can also be of other shapes.

[0034] The adapter mounting portion 25 can be provided in a flange shape. The adapter mounting portion 25 can be provided with two adapter mounting holes 21. The adapter 2 can be mounted to the fuel cell stack 6 by inserting bolts into the adapter mounting holes 21, as Figure 5 and 6 shown.

[0035] Although Figure 3 and 4 show that the adapter mounting portion 25 has two adapter mounting holes 21, the number of adapter mounting holes 21 is not limited thereto, but can be set to other numbers according to the available mounting space and actual needs. The shape of the adapter mounting portion 25 is not limited to the flange shape and can be modified according to needs. In addition, the fixation between the adapter 2 and the fuel cell stack 6 is not limited to bolt connection, but can be set to other forms known in the art, such as snap connection, etc.

[0036] As Figure 6 specifically shown, the inner hole of the adapter 2 can have a large-diameter section 29 and a small-diameter section 28 extending from the large-diameter section 29 towards the end close to the connecting member 1, so as to form a stepped portion 30 therebetween. The size of the small-diameter section 28 is the same as that of the second channel 17, so that when the adapter 2 is mounted to the connecting member 1, the small-diameter section 28 is flush with the second channel 17 to facilitate the smooth flow of the cooling fluid.

[0037] Both the first seal 4 and the second seal 3 can be made of an insulating deformable material, such as a rubber seal, such as a fluororubber seal, etc., not limited thereto.

[0038] The following Figure 5 and Figure 6 describe the process of connecting the connection assembly according to the present application to the coolant interface 5 of the fuel cell stack 6.

[0039] First, install the first seal 4 in the first groove 27 of the adapter 2, and then place the adapter 2 over the coolant interface 5 of the stack 6, such that the coolant interface 5 is inserted within the large diameter section 28. The coolant interface 5 is tubular, and after being installed in the adapter 2, the inner wall of the coolant interface 5 is flush with the small diameter section 28 and the second channel 17. The end of the coolant interface 5 is close to the step portion 30, and the outer wall of the coolant interface 5 is close to the large diameter section 29 of the adapter 2, and the lower end face 23 of the adapter 2 abuts against the stack 6. At this time, the first seal 4 located in the first groove 26 abuts against the outer wall of the coolant interface 5 and deforms under the pressure of the coolant interface 5 and the adapter 2, thereby generating a radial sealing effect between the adapter 2 and the coolant interface 5. Meanwhile, the adapter 2 can be fixed to the stack 6 by, for example, bolts passing through the adapter mounting holes 21.

[0040] Then, place the second seal 3 in the second groove 27 in the upper end face 22 of the adapter 2, and subsequently place the connector 1 and the adapter 2 together such that the upper end face 22 of the adapter 2 faces the lower end face 11 of the connector mounting portion 15 of the connector 1, and align the small diameter section 28 of the adapter 2 with the second channel 17. The second seal 3 located in the second groove 27 in the upper end face 22 of the adapter 2 abuts against the lower end face 11 of the connector 1. Fix the connector 1 to the stack 6 by, for example, bolts passing through the connector mounting holes 13. At this time, the second seal 3 is pressed between the upper end face 22 of the adapter 2 and the lower end face 11 of the connector 1 and deforms, thereby achieving axial sealing between the connector 1 and the adapter 2.

[0041] The above describes the case where the connector mounting holes 13 and the adapter mounting holes 21 are not aligned and are separately connected to the stack 6 by their respective bolts, but the present application is not limited thereto. The connector mounting holes 13 and the adapter mounting holes 21 can also be set to be aligned and simultaneously fixed to the stack 6 by the same bolts, which can save the number of components.

[0042] In the present application, the adapter 2, the first seal 4, and the second seal 3 can all be made of insulating materials. For example, the adapter 2 can be molded from a polyester material, but is not limited thereto.

[0043] The connector 1 and the adapter 2 can be made of the same material or different materials. For example, the connector 1 can be made of a metal material or a polyester material.

[0044] When connecting the coolant circuit of a fuel cell system and each fuel cell in a multi-stack structure using the above connection components, by adding an adapter 2 with an axial seal (i.e., the second seal 3) and a radial seal (i.e., the first seal 4), and the axial seal is installed in the groove of the upper end face 22 of the adapter 2, and the radial seal is placed in the groove inside the adapter 2. When the adapter 2 equipped with the axial seal and the radial seal is sleeved on the fuel cell coolant interface 5, the lower end face 23 of the adapter is fixed and fitted to the fuel cell 6 by bolts passing through the adapter mounting holes 21, completing the action of compressing the radial seal 4 to achieve radial sealing; the lower end face 11 of the connecting member is fitted to the upper end face 22 of the adapter, and after compressing the axial seal 3 through the mounting hole 13, it is installed and fixed on the fuel cell 6 to achieve axial sealing. In this way, the structure that was all radial sealing in the prior art is adjusted to adapt to radial sealing at one end of the connection component and match axial sealing at the other end, which reduces the requirement for part tolerances when all are radial sealing and also reduces the leakage risk between the connecting member 1 and the fuel cell 6. This enables the cooling circuit of the fuel cell system including the multi-stack structure and even the entire fuel cell system to operate stably and reliably.

[0045] In addition, the solution of the present application can also be applied to multiple coolant interfaces 5 simultaneously, not limited to the two shown in the figure, which improves the flexibility of use.

[0046] Through the one-to-many connection structure and the adjustability of the axial seal, the positional tolerance requirements of multiple interfaces on the fuel cell are reduced, adapting to the tolerance accumulation during the processing and assembly of the connecting member.

[0047] Although it is described in the present application that the connection component is used for connecting the coolant interfaces of each fuel cell in the multi-stack structure of the fuel cell system, the present application is not limited to this. On the contrary, it can be applied to various application places that need to seal air, hydrogen, coolant, etc., to achieve stable sealed connection of one or more interfaces.

[0048] The present application has been described in detail in combination with specific embodiments. Obviously, the above description and the embodiments shown in the drawings should be understood as exemplary and do not constitute a limitation to the present application. For those skilled in the art, various variations or modifications can be made without departing from the spirit of the present application, and these variations or modifications do not depart from the scope of the present application.

Claims

1. A connection assembly, which is connected between a coolant circuit of a fuel cell system having a multi-stack structure and a stack coolant interface, characterized in that: The connection component comprises: a coolant inlet (10) in communication with a coolant circuit of the fuel cell system and at least one coolant outlet (20) in communication with a coolant interface (5) of the stack, A connecting member (1), the connecting member (1) defining a first channel (16) leading to the cooling liquid inlet (10) and at least one second channel (17) leading to the cooling liquid outlet (20); and at least one adapter (2), each of the adapters (2) cooperating with the connector (1) at the end of each of the second channels (17) to define the coolant outlet (20) and connected to the stack coolant interface (5), Each adapter (2) is radially sealed and connected to the stack coolant interface (5) via a first seal (4), and each adapter (2) is axially sealed and connected to the connector (1) via a second seal (3).

2. The connection assembly according to claim 1, characterized in that: The adapter (2) comprises a main body (24) to be matched with the connector (1) and an adapter mounting portion (25) extending from the main body (24); the main body (24) is cylindrical; a first groove (26) extending in a circumferential direction is provided on the inner wall of the main body (24); the first sealing member (4) is installed in the first groove (26) and partially protrudes from the inner wall of the main body (24); when the adapter (2) is installed on the stack coolant interface (5), the first sealing member (4) abuts against the outer wall of the stack coolant interface (5).

3. The connection assembly according to claim 2, characterized in that: The adapter mounting portion (25) has a plurality of adapter mounting holes (21), and the adapter (2) is mounted to the battery stack (6) by means of bolts passing through the adapter mounting holes (21).

4. The connection assembly according to claim 2, characterized in that: A second groove (27) extending in a circumferential direction is provided on the upper end surface (22) of the main body (24) of the adapter (2) facing the connecting member (1); the second sealing member (3) is installed in the second groove (27) and partially protrudes from the upper end surface (22); when the adapter (2) is installed to the connecting member (1), the second sealing member (3) abuts against the lower end surface (11) of the connecting member (1) facing the adapter (2).

5. The connection assembly according to claim 1, characterized in that: The first sealing member (4) is a lip-shaped rubber sealing ring.

6. The connection assembly according to claim 1, characterized in that: The second sealing member (3) is an O-shaped rubber sealing ring.

7. The connection assembly according to claim 2, characterized in that: The connector (1) has a connector mounting portion (15) near each coolant outlet (20), and the connector mounting portion (15) is mounted to the fuel cell stack (6) when the adapter (2) is located between the connector (1) and the fuel cell stack (6).

8. The connection assembly according to claim 7, characterized in that: The connector mounting portion (15) has a plurality of connector mounting holes (13), and the connector (1) is mounted to the battery stack (6) by means of bolts passing through the connector mounting holes (13).

9. The connection assembly according to claim 8, characterized in that: The connector mounting hole (13) of the connector mounting portion (15) and the adapter mounting hole (21) of the adapter mounting portion (25) are configured to be aligned or not aligned.

10. A fuel cell system, characterized in that: It comprises a multi-stack structure having a plurality of stacks (6), and a connection assembly according to any one of claims 1 to 9, wherein the connection assembly is connected between a coolant interface of each stack of the multi-stack structure and a coolant circuit of the fuel cell system.

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