Hydrogen fuel cell stack

Abstract

The present application relates to a kind of hydrogen fuel cell stacks, including distribution manifold and cell, cell is sleeved on distribution manifold, distribution manifold has a passage, passage is arranged along the axial direction of distribution manifold, and passage penetrates the end of distribution manifold, and the side of distribution manifold is provided with an opening, and the opening is communicated with passage;The size of the inner diameter of distribution manifold gradually increases along the direction of gas flow.The present application adopts variable cross-section design to improve the consistency of the overall flow distribution of the stack, thereby improving the drainage performance of the stack;And cell is stacked on distribution manifold, which can reduce the deviation during the assembly of the stack, improve the overall stiffness of the stack, and avoid the problem of waist collapse caused by the length of the stack.

Description

Technical Field

[0001] This invention relates to the field of fuel cell manufacturing technology, and in particular to a hydrogen fuel cell stack. Background Technology

[0002] Hydrogen fuel's greatest advantages as an energy source are its pollution-free nature, high efficiency, and recyclability, making it a future direction for new energy development and one of the main energy development directions for fuel cell vehicles. A typical fuel cell stack consists of multiple individual fuel cells stacked together. Each individual fuel cell includes an anode bipolar plate, a membrane electrode assembly (MEA), and a cathode bipolar plate. The bipolar plates have distribution channels and reaction zones. The distribution channels provide pathways for delivering hydrogen, air, and coolant into the bipolar plate reaction zone. Since the distribution channels deliver reactant gases and coolant to each individual fuel cell, their design directly affects the uniformity of flow distribution among the individual fuel cells in the stack, thus impacting the overall stack performance.

[0003] Existing distribution channels generally have a fixed cross-sectional shape. The distribution channel along the flow direction of the outlet is not conducive to the discharge of generated water. Moreover, the overall rigidity of the battery stack is poor. For long battery stacks, the middle of the battery stack is prone to collapse. Generally, it is necessary to add support devices on the outside of the battery stack to prevent the collapse of large battery stacks. The structure is cumbersome, and in severe cases, it may lead to the battery stack insulation value not meeting the standard.

[0004] Therefore, there is an urgent need to develop a hydrogen fuel cell stack to overcome the aforementioned technical deficiencies in existing technologies. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the technical defects existing in the prior art, and to propose a hydrogen fuel cell stack in which the inner diameter of the distribution manifold gradually increases along the gas flow direction to improve the consistency of the overall flow distribution of the stack, thereby improving the drainage performance of the stack; and the battery cells are stacked on the distribution manifold to reduce the deviation in the stack assembly process, improve the overall rigidity of the stack, and avoid the problem of the stack collapsing due to being too long.

[0006] To address the aforementioned technical problems, the present invention provides a hydrogen fuel cell stack, comprising:

[0007] A distribution manifold has a channel arranged along the axial direction of the distribution manifold and passing through one end of the distribution manifold. An opening is provided on one side of the distribution manifold, and the opening communicates with the channel.

[0008] A single battery cell is fitted onto the main distribution pipe;

[0009] The inner diameter of the main distribution pipe gradually increases along the gas flow direction.

[0010] In one embodiment of the present invention, it further includes end plates, two oppositely disposed end plates being sleeved on the distribution manifold to clamp the battery cell.

[0011] In one embodiment of the present invention, the end plate is provided with bosses at both ends, and a first mounting part is provided on the bosses, and the distribution manifold is disposed on the first mounting part.

[0012] In one embodiment of the present invention, a second mounting portion is provided on the battery cell, and the distribution manifold is disposed on the second mounting portion.

[0013] In one embodiment of the present invention, the second mounting portion is a socket disposed on the battery cell.

[0014] In one embodiment of the present invention, the main distribution pipe is inserted into the socket.

[0015] In one embodiment of the invention, the outer diameter of the distribution manifold remains the same along the gas flow direction.

[0016] In one embodiment of the present invention, the distribution manifold is provided with a chamfer.

[0017] In one embodiment of the present invention, the distribution manifold includes a first gas input manifold, a first gas output manifold, a second gas input manifold, and a second gas output manifold. The first gas input manifold and the second gas output manifold are disposed at one end of the end plate, and the second gas input manifold and the first gas output manifold are disposed at the other end of the end plate.

[0018] In one embodiment of the present invention, the battery cell is provided with a flow channel, the flow channel being directly opposite the opening of the distribution manifold, so that gas can flow between the distribution manifold and the flow channel.

[0019] The technical solution of the present invention has the following advantages compared with the prior art:

[0020] The hydrogen fuel cell stack of the present invention has a distribution manifold whose inner diameter gradually increases along the gas flow direction to improve the consistency of the overall flow distribution of the stack, thereby improving the drainage performance of the stack; and the stacking of individual cells on the distribution manifold can reduce the deviation during the stack assembly process, improve the overall rigidity of the stack, and avoid the problem of the stack collapsing due to excessive length. Attached Figure Description

[0021] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the structure of a hydrogen fuel cell stack proposed in an embodiment of the present invention.

[0023] Figure 2 for Figure 1 A partial structural diagram.

[0024] Figure 3 This is a schematic diagram of the structure of the first gas input main pipe proposed in an embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the structure of the first gas output main pipe proposed in an embodiment of the present invention.

[0026] The following are the labels in the diagram: 1. Battery cell; 11. Flow channel; 12. Second mounting part; 2. End plate; 21. Boss; 22. First mounting part; 3. First gas inlet manifold; 4. First gas outlet manifold; 5. Second gas inlet manifold; 6. Second gas outlet manifold; 7. Channel; 8. Opening. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0028] Reference Figures 1 to 4 As shown, this embodiment of the invention provides a hydrogen fuel cell stack, including a distribution manifold and individual battery cells 1. The individual battery cells 1 are sleeved on the distribution manifold. The distribution manifold has a channel 7, which is arranged along the axial direction of the distribution manifold and passes through one end of the distribution manifold. An opening 8 is provided on one side of the distribution manifold, which communicates with the channel 7. The inner diameter of the distribution manifold gradually increases along the gas flow direction. That is, the distribution manifold of this invention adopts a variable cross-section design to improve the consistency of the overall flow distribution of the fuel cell stack, thereby improving the drainage performance of the fuel cell stack. Furthermore, the stacking of individual battery cells 1 on the distribution manifold can reduce the deviation during the fuel cell stack assembly process, improve the overall rigidity of the fuel cell stack, and avoid the problem of the stack collapsing due to excessive length.

[0029] Furthermore, the hydrogen fuel cell stack provided in this embodiment of the invention also includes end plates 2, with two oppositely arranged end plates 2 sleeved on the distribution manifold to clamp the battery cells 1. Preferably, the battery cells 1 are stacked between the two end plates 2 and fastened by steel strips or screws.

[0030] The end plate 2 has protrusions 21 at both ends, and a first mounting part 22 is provided on the protrusion 21. The main distribution pipe is disposed on the first mounting part 22. Preferably, the first mounting part 22 is a first insertion hole provided on the protrusion 21, the first insertion hole penetrates through the two end faces of the end plate 2, and the main distribution pipe is inserted into the first insertion hole.

[0031] Furthermore, the distribution manifold is chamfered, which can guide the end plate 2 as it is mounted on the distribution manifold, thus facilitating the assembly of the fuel cell stack.

[0032] Furthermore, the aforementioned first insertion hole is located on the boss 21, that is, the distribution main pipe is wrapped by the larger inner side wall of the boss 21. On the one hand, it can provide better protection for the distribution main pipe, and on the other hand, it can increase the contact area between the distribution main pipe and the end plate 2, improve the support of the distribution main pipe for the entire battery stack, and avoid the problem of the stack collapsing due to being too long.

[0033] It should be emphasized that the outer diameter of the distribution manifold remains the same along the gas flow direction, that is, the outer diameter of the distribution manifold is constant. Therefore, the size of the first insertion hole on the end plate 2 is the same, which facilitates the consistent processing of the first insertion hole on the end plate 2.

[0034] Similarly, the aforementioned battery cell 1 is provided with a second mounting portion 12, and the distribution manifold is disposed on the second mounting portion 12. Preferably, the second mounting portion 12 is a second insertion hole provided on the battery cell 1, and the distribution manifold is inserted into the second insertion hole. The distribution manifold is provided with a chamfer, which can provide a certain guiding effect for the battery cell 1 to be fitted onto the distribution manifold, facilitating the assembly of the fuel cell stack. It should also be emphasized that the outer diameter of the distribution manifold remains the same along the gas flow direction, that is, the outer diameter of the distribution manifold is constant. Therefore, the size of the second insertion hole on the battery cell 1 is the same, which facilitates the consistent processing of the second insertion hole on the battery cell 1.

[0035] The battery cell 1 is provided with a flow channel 11, which is directly opposite the opening 8 of the distribution manifold, so that gas can flow between the distribution manifold and the flow channel 11. The distribution manifold includes a first gas input manifold 3, a first gas output manifold 4, a second gas input manifold 5, and a second gas output manifold 6. The first gas input manifold 3 and the second gas output manifold 6 are located at one end of the end plate 2, and the second gas input manifold 5 and the first gas output manifold 4 are located at the other end of the end plate 2. Preferably, the first gas input manifold 3 is an air input manifold, the first gas output manifold 4 is an air output manifold, the second gas input manifold 5 is a hydrogen input manifold, and the second gas output manifold 6 is a hydrogen output manifold. The air input manifold and the hydrogen output manifold are located at one end of the end plate 2, and the hydrogen input manifold and the air output manifold are located at the other end of the end plate 2. Hydrogen enters the battery cell 1 through the hydrogen input manifold of the fuel cell stack, and air enters the battery cell 1 through the air input manifold of the fuel cell stack. Part of the water produced by the reaction and the remaining hydrogen are discharged through the hydrogen output manifold of the fuel cell stack, and the other part of the water produced and the remaining air are discharged through the air output manifold of the fuel cell stack.

[0036] Furthermore, the structure of the aforementioned air input manifold is as follows: Figure 3 As shown, the air input manifold has a channel 7, which is arranged along the axial direction of the air input manifold and extends through one end of the air input manifold. An opening 8 is provided on one side of the air input manifold, which connects to the channel 7. The inner diameter of the air input manifold gradually increases along the gas flow direction; that is, after air enters the air input manifold, it enters each battery cell 1 through the channel 7, and the cross-section of the air input manifold gradually increases along the flow direction. According to Bernoulli's equation, when fluid flows through an expanding pipe, the fluid pressure increases along the flow direction. Therefore, this invention, by adopting an expanding design for the air input manifold, can increase the pressure at the tail end, thereby increasing the inlet pressure of the tail-end battery cell 1, increasing the flow rate of the tail-end battery cell 1, avoiding gas shortage at the tail end, and improving the fluid distribution uniformity of the fuel cell stack. Of course, the hydrogen input manifold adopts the same inventive concept as the air input manifold.

[0037] Furthermore, the air outlet manifold of the aforementioned air outlet manifold is as follows: Figure 4 As shown, the reaction products on the air side and the remaining air from the reaction enter the air outlet manifold through channel 7 and flow out through the outlet of the air outlet manifold. Along the flow direction, the cross-section of the air outlet manifold gradually increases, meaning channel 7 slopes downwards along the flow direction. This facilitates the discharge of liquid water from the air outlet manifold, preventing the accumulation of liquid water and reducing pressure fluctuations. The hydrogen outlet manifold adopts the same design concept as the air outlet manifold.

[0038] Compared to existing battery stack arrangements, this invention features a separate air inlet manifold, air outlet manifold, hydrogen inlet manifold, and hydrogen outlet manifold. The individual battery cells 1 are stacked into a stack by passing through the separately designed distribution manifold, which can reduce positioning deviations during the stack installation process. At the same time, no additional stack positioning design is required during the stacking process, thus improving stacking efficiency.

[0039] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A hydrogen fuel cell stack, characterized by: The application relates to a battery cell, and discloses a battery cell and an end plate. The battery cell comprises a distribution main pipe, a battery cell and an end plate. The distribution main pipe has a channel, the channel is arranged along the axial direction of the distribution main pipe, and the channel penetrates one end of the distribution main pipe. One side of the distribution main pipe is provided with an opening, and the opening is communicated with the channel. The battery cell is sleeved on the distribution main pipe.

2. A hydrogen fuel cell stack according to claim 1, characterised in that: The inner diameter of the distribution main pipe gradually increases along the gas flow direction.

3. A hydrogen fuel cell stack according to claim 2, characterised in that: The battery cell is provided with a flow channel, and the flow channel is opposite to the opening of the distribution main pipe, so that the gas flows between the distribution main pipe and the flow channel.

4. A hydrogen fuel cell stack according to any one of claims 1 to 3, characterised in that: The end plate is arranged on the distribution main pipe to clamp the battery cell.

5. A hydrogen fuel cell stack according to claim 4, characterised in that: The two ends of the end plate are provided with bosses, the bosses are provided with first mounting parts, and the distribution main pipe is arranged on the first mounting parts.

6. A hydrogen fuel cell stack according to claim 5, characterised in that: The battery cell is provided with second mounting parts, and the distribution main pipe is arranged on the second mounting parts.

7. A hydrogen fuel cell stack according to any one of claims 1 to 3, characterised in that: The second mounting parts are insertion holes arranged on the battery cell.

8. A hydrogen fuel cell stack according to any one of claims 1 to 3, characterised in that: The distribution main pipe is inserted into the insertion holes.

9. A hydrogen fuel cell stack according to claim 2 or 3, characterised in that: The outer diameter of the distribution main pipe remains unchanged along the gas flow direction. The distribution main pipe is provided with a chamfer. The distribution main pipe comprises a first gas input main pipe, a first gas output main pipe, a second gas input main pipe and a second gas output main pipe. The first gas input main pipe and the second gas output main pipe are arranged at one end of the end plate. The second gas input main pipe and the first gas output main pipe are arranged at the other end of the end plate.

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