A hydrogen fuel cell stack

Abstract

The application discloses a hydrogen fuel cell stack and relates to the technical field of fuel cells. The application is characterized in that a spiral device is arranged at a hydrogen inlet, so that liquid water entrained in circulating hydrogen is effectively dispersed and redistributed before entering the stack. Under the spiral guiding action, the liquid water is converted into fine water droplets, and is sequentially introduced into hydrogen inlet channels of a gas inlet false cell group and a true cell group under the action of air flow, so that the liquid water is avoided from directly rushing into a single cell in the form of concentrated liquid flow. The structure can significantly weaken the impact of concentrated discharge of liquid water on local single cell electrochemical reaction and structural parts under low current density working conditions, so that the liquid water is taken out by multiple cells in a more moderate and dispersed manner, and the hydrogen distribution uniformity in the stack is improved, and the overall operation stability and durability are improved.

Description

Technical Field

[0001] This application relates to the field of fuel cell technology, specifically to a hydrogen fuel cell stack. Background Technology

[0002] A hydrogen fuel cell stack (hereinafter referred to as a stack) is a structure consisting of multiple single cells stacked together to form a high-power battery module. The stack has the following flow channels: hydrogen inlet and outlet; air inlet and outlet; cooling water inlet and outlet. Because hydrogen is not completely consumed during the reaction, the system collects the exhaust gas produced after the stack reaction. After passing through a gas-liquid separator, the separated hydrogen is reinjected into the stack through a hydrogen circulation pipeline, thereby improving the utilization rate of hydrogen. During this process, due to the influence of factors such as the filtration level of the gas-liquid separator, humidity, and temperature in the circulation pipeline, the separated hydrogen will still carry some liquid water into the anode reaction channel of the stack. At low charge density, because the airflow and pressure in the anode channel are relatively small, the liquid water cannot be dispersed. The liquid water may concentrate in a cell at the gas inlet end of the stack and be carried out. At this time, the performance of the cell carrying out liquid water will be affected and fluctuate. In severe cases (when a large amount of liquid water accumulates and a single cell is flooded), the performance of the cell will be low. Summary of the Invention

[0003] Based on this, a hydrogen fuel cell stack is provided to solve the technical problem that when circulating hydrogen enters the current fuel cell stack during use, some liquid water is introduced. When the electrical density is low, this liquid water may be discharged from a cell at the gas port end of the stack. At this time, the cell is affected by the liquid water and is prone to low performance.

[0004] On one hand, a hydrogen fuel cell stack is provided, including a gas inlet end plate, a gas inlet dummy battery pack, a real battery pack, and a spiral device. The gas inlet end plate, the gas inlet dummy battery pack, and the real battery pack are stacked sequentially. The hydrogen fuel cell stack has a hydrogen flow channel inside. The hydrogen flow channel has a hydrogen inlet and a hydrogen outlet in a vertical direction on the surface of the gas inlet end plate. The spiral device is installed in the hydrogen inlet. Multiple first hydrogen inlet channels are provided in the gas inlet dummy battery pack, and multiple second hydrogen inlet channels are provided in the real battery pack. The hydrogen inlet intersects and communicates with the first hydrogen inlet channels and the second hydrogen inlet channels. The hydrogen and liquid water mixture input from the hydrogen inlet is spirally guided by the spiral device, causing the liquid water in the hydrogen and liquid water mixture to be dispersed into water droplets and then sequentially enter the first hydrogen inlet channels and the second hydrogen inlet channels, where it is dispersed and carried out by the airflow.

[0005] In one embodiment, the spiral device includes a main shaft, a rotating guide vane, and a fixed end plate. The rotating guide vane is rotatably arranged along the main shaft, and the fixed end plate is connected to the rotating guide vane. The edge of the hydrogen inlet is provided with a groove, and the fixed end plate is engaged in the groove. The main shaft coincides with the axis of symmetry of the hydrogen inlet.

[0006] In one embodiment, the main shaft, the rotating guide vane, and the fixed end plate are integrally formed, and the material of the spiral device includes polyphenylene sulfide.

[0007] In one embodiment, the outer diameter of the rotating guide vane along the main shaft is less than or equal to the inner diameter of the hydrogen inlet.

[0008] In one embodiment, the hydrogen fuel cell stack is provided with an air circulation channel and a coolant circulation channel inside. The air circulation channel has an air inlet and an air outlet in a vertical direction on the surface of the air inlet end plate. The coolant circulation channel has a coolant inlet and a coolant outlet in a vertical direction on the surface of the air inlet end plate. The exhaust gas output from the air outlet, the coolant outlet and the hydrogen outlet enters the hydrogen inlet after liquid water is separated through the circulating hydrogen inlet common pipeline.

[0009] In one embodiment, the outlet of the circulating hydrogen inlet common pipeline is connected to the hydrogen inlet common pipeline, and the hydrogen inlet common pipeline is connected to the hydrogen inlet. The hydrogen containing liquid water output from the circulating hydrogen inlet common pipeline mixes with the dry hydrogen in the hydrogen inlet common pipeline to form the hydrogen and liquid water mixture, which then enters the hydrogen inlet.

[0010] In one embodiment, the circulating hydrogen intake common pipeline includes a tail gas recovery pipeline, a gas-water separator and a hydrogen recovery pipeline connected in sequence. The gas-water separator is provided with a liquid water discharge pipeline, and the hydrogen recovery pipeline is provided with a hydrogen circulation pump.

[0011] In one embodiment, the circulating hydrogen intake common pipeline includes a hydrogen tank and a hydrogen supply pipeline, the hydrogen tank being connected to the hydrogen inlet via the hydrogen supply pipeline, and the hydrogen recovery pipeline being connected to the hydrogen supply pipeline.

[0012] In one embodiment, the vent dummy battery pack consists of multiple single cells that do not participate in the redox reaction, while the real battery pack consists of multiple single cells that participate in the redox reaction.

[0013] In one embodiment, the thickness of the dummy battery pack is less than the thickness of the real battery pack.

[0014] The aforementioned hydrogen fuel cell stack incorporates a spiral device at the hydrogen inlet. This device effectively disperses and redistributes liquid water entrained in the circulating hydrogen before it enters the stack. Guided by the spiral, the liquid water is transformed into tiny droplets and, propelled by the airflow, sequentially enters the hydrogen inlet channels of the dummy and real battery cells. This prevents liquid water from directly flooding any single cell in a concentrated flow. This structure significantly reduces the impact of concentrated liquid water discharge on localized electrochemical reactions and structural components under low electrical density conditions. It allows the liquid water to be carried out by multiple cells in a gentler, more dispersed manner, thereby improving the uniformity of hydrogen distribution within the stack and enhancing overall operational stability and durability. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the exploded structure of a hydrogen fuel cell stack in one embodiment of this application;

[0017] Figure 2 This is a cross-sectional view of a hydrogen fuel cell stack in one embodiment of this application;

[0018] Figure 3 This is a top view of a hydrogen fuel cell stack in one embodiment of this application;

[0019] Figure 4 This is a schematic diagram of the structure of the spiral device installed inside the hydrogen inlet in one embodiment of this application;

[0020] Figure 5 This is a cross-sectional view of the spiral device installed inside the hydrogen inlet in one embodiment of this application;

[0021] Figure 6 This is a schematic diagram of the connection structure of the hydrogen fuel cell stack, the circulating hydrogen inlet common pipeline and the hydrogen inlet common pipeline in one embodiment of this application;

[0022] The markings in the diagram are as follows:

[0023] The hydrogen fuel cell stack includes: 10, gas inlet end plate 1, hydrogen inlet 11, slot 111, hydrogen outlet 12, air inlet 13, air outlet 14, coolant inlet 15, coolant outlet 16, gas inlet dummy battery pack 2, first hydrogen inlet channel 21, real battery pack 3, second hydrogen inlet channel 31, spiral device 4, hydrogen flow channel 5, air flow channel 6, coolant flow channel 7, main shaft 41, rotating guide vane 42, fixed end plate 43, circulating hydrogen inlet common pipeline 20, exhaust gas recovery pipe 201, gas-water separator 202, hydrogen recovery pipeline 203, liquid water discharge pipeline 204, hydrogen circulation pump 205, hydrogen inlet common pipeline 30, hydrogen tank 301, and hydrogen supply pipeline 302. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0025] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0026] Please see Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5This application provides a hydrogen fuel cell stack 10, including a gas inlet end plate 1, a gas inlet dummy battery pack 2, a real battery pack 3, and a spiral device 4. The gas inlet end plate 1, the gas inlet dummy battery pack 2, and the real battery pack 3 are stacked sequentially. The hydrogen fuel cell stack 10 has a hydrogen flow channel 5 inside. The hydrogen flow channel 5 has a hydrogen inlet 11 and a hydrogen outlet 12 in the vertical direction on the surface of the gas inlet end plate 1. The spiral device 4 is installed in the hydrogen inlet 11. The gas inlet dummy battery pack 2 has multiple first hydrogen inlet channels 21, and the real battery pack 3 has multiple second hydrogen inlet channels 31. The hydrogen inlet 11 intersects and communicates with the first hydrogen inlet channels 21 and the second hydrogen inlet channels 31. The hydrogen and liquid water mixture input from the hydrogen inlet 11 is spirally guided by the spiral device 4, causing the liquid water in the hydrogen and liquid water mixture to be dispersed into water droplets and then sequentially enter the first hydrogen inlet channels 21 and the second hydrogen inlet channels 31, where it is dispersed and carried out by the airflow.

[0027] By incorporating a spiral device 4 at the hydrogen inlet 11, liquid water entrained in the circulating hydrogen is effectively dispersed and redistributed before entering the fuel cell stack. Guided by the spiral, the liquid water is transformed into tiny droplets and, propelled by the airflow, sequentially enters the hydrogen inlet channels of the dummy battery pack 2 and the real battery pack 3. This prevents liquid water from directly flooding a single cell in a concentrated flow. This structure significantly reduces the impact of concentrated liquid water discharge on localized electrochemical reactions and structural components under low electrical density conditions, allowing the liquid water to be carried out by multiple cells in a gentler, more dispersed manner. This improves the uniformity of hydrogen distribution within the fuel cell stack, enhancing overall operational stability and durability.

[0028] Please see Figure 4 , Figure 5 In this embodiment, the spiral device 4 includes a main shaft 41, a rotating guide vane 42, and a fixed end plate 43. The rotating guide vane 42 is rotatably arranged along the main shaft 41, and the fixed end plate 43 is connected to the rotating guide vane 42. The edge of the hydrogen inlet 11 is provided with a slot 111, and the fixed end plate 43 is engaged in the slot 111. The main shaft 41 coincides with the axis of symmetry of the hydrogen inlet 11.

[0029] Specifically, the spiral device 4 is constructed by consisting of a main shaft 41, rotating guide vanes 42, and a fixed end plate 43. A slot 111 structure ensures reliable installation and engagement with the hydrogen inlet 11, allowing the spiral device 4 to stably remain on the axis of the hydrogen inlet 11 during operation. This guarantees that the incoming hydrogen and liquid water mixture always flows along a symmetrical and controllable spiral path. This structure not only improves the consistency and repeatability of liquid water dispersion and guiding effects but also avoids the adverse effects of device misalignment on airflow resistance and water distribution, making the spiral guiding action more stable and reliable.

[0030] In this embodiment, the main shaft 41, the rotating guide vane 42 and the fixed end plate 43 are integrally formed, and the material of the spiral device 4 includes polyphenylene sulfide (PPS).

[0031] By designing the main shaft 41, rotating guide vanes 42, and fixed end plate 43 as an integrally molded structure and using polyphenylene sulfide (PPS) material, the spiral device 4 meets the requirements for hydrogen resistance, corrosion resistance, and temperature resistance while possessing good structural strength and molding precision. The integrated structure reduces the number of parts and assembly processes, lowers manufacturing and assembly errors, and improves long-term reliability. It also facilitates rapid integration into existing mass-produced fuel cell stacks or later additions, thereby effectively controlling costs while ensuring performance.

[0032] In this embodiment, the outer diameter of the rotating guide vane 42 along the main shaft 41 is less than or equal to the inner diameter of the hydrogen inlet 11. By limiting the outer diameter of the rotating guide vane 42 along the main shaft 41 to be less than or equal to the inner diameter of the hydrogen inlet 11, the spiral device 4 achieves effective disturbance and guidance of the mixed gas without significantly increasing the flow resistance of the hydrogen inlet 11. This dimensional relationship ensures that the liquid water can fully contact and be dispersed by the spiral vane, while avoiding blockage of the air intake channel or excessive pressure loss due to excessive structure, thus achieving a balance between water management effectiveness and air intake efficiency.

[0033] Please see Figure 3 , Figure 6 In this embodiment, the hydrogen fuel cell stack 10 is provided with an air circulation channel 6 and a coolant circulation channel 7. The air circulation channel 6 is provided with an air inlet 13 and an air outlet 14 in the vertical direction on the surface of the air inlet end plate 1. The coolant circulation channel 7 is provided with a coolant inlet 15 and a coolant outlet 16 in the vertical direction on the surface of the air inlet end plate 1. The exhaust gas output from the air outlet 14, the coolant outlet 16 and the hydrogen outlet 12 enters the hydrogen inlet 11 after the liquid water is separated by the circulating hydrogen inlet common pipeline 20.

[0034] By simultaneously incorporating an air circulation channel 6 and a coolant circulation channel 7 within the fuel cell stack, and ensuring that the exhaust gases from the air outlet 14, coolant outlet 16, and hydrogen outlet 12 are uniformly channeled into the common circulating hydrogen inlet pipeline 20, centralized recovery and reuse of exhaust gases and liquid water generated during fuel cell stack operation are achieved. Under this structure, circulating hydrogen containing liquid water can undergo moisture redispersion treatment with the spiral device 4 before re-entering the hydrogen inlet 11, improving fuel cell stack water management at the system level, reducing external discharge losses, and increasing overall system efficiency.

[0035] Please see Figure 6 In this embodiment, the output port of the circulating hydrogen inlet common pipeline 20 is connected to the hydrogen inlet common pipeline 30, and the hydrogen inlet common pipeline 30 is connected to the hydrogen inlet 11. The hydrogen containing liquid water output from the circulating hydrogen inlet common pipeline 20 mixes with the dry hydrogen in the hydrogen inlet common pipeline 30 to form the hydrogen and liquid water mixture, which then enters the hydrogen inlet 11.

[0036] By connecting the output port of the circulating hydrogen inlet common pipeline 20 to the hydrogen inlet common pipeline 30, the recovered hydrogen containing liquid water is fully mixed with the dry hydrogen from the hydrogen source before entering the fuel cell stack. This dilutes the liquid water content and regulates the gas humidity to a certain extent. This mixing method, combined with the dispersing effect of the spiral device 4, further reduces the risk of liquid water accumulating in a single location, resulting in a more balanced state of the hydrogen entering the fuel cell stack and contributing to a stable reaction environment.

[0037] In this embodiment, the circulating hydrogen intake common pipeline 20 includes a tail gas recovery pipeline 201, a gas-water separator 202 and a hydrogen recovery pipeline 203 connected in sequence. The gas-water separator 202 is provided with a liquid water discharge pipeline 204, and the hydrogen recovery pipeline 203 is provided with a hydrogen circulation pump 205.

[0038] Specifically, by sequentially installing a tail gas recovery pipe 201, a gas-water separator 202, and a hydrogen recovery pipe 203 in the common circulating hydrogen inlet pipeline 20, and discharging a portion of liquid water at the gas-water separator 202, the circulating hydrogen undergoes gas-water separation before returning to the fuel cell stack. This structure effectively reduces the total amount of liquid water entering the fuel cell stack, while ensuring the stability of the circulating hydrogen flow rate under the action of the hydrogen circulation pump 205. Working in conjunction with the spiral device 4 at the fuel cell stack inlet, it achieves graded water management and improves the reliability of system operation.

[0039] In this embodiment, the circulating hydrogen inlet common pipeline 20 includes a hydrogen tank 301 and a hydrogen supply pipeline 302. The hydrogen tank 301 is connected to the hydrogen inlet 11 through the hydrogen supply pipeline 302, and the hydrogen recovery pipeline 203 is connected to the hydrogen supply pipeline 302.

[0040] By incorporating the hydrogen tank 301 and hydrogen supply pipeline 302 into the circulating hydrogen intake common pipeline 20 system, and connecting the hydrogen recovery pipeline 203 to the hydrogen supply pipeline 302, a unified supply and distribution of fresh and recovered hydrogen is achieved. This structure facilitates flexible adjustment of the hydrogen composition entering the fuel cell stack under different operating conditions. While the recovered hydrogen is reused, its humidity and purity are improved by the help of fresh hydrogen, further working with the spiral device 4 to reduce the adverse effects of liquid water on the fuel cell stack performance.

[0041] In this embodiment, the dummy battery pack 2 consists of multiple single cells that do not participate in the redox reaction, while the real battery pack 3 consists of multiple single cells that participate in the redox reaction.

[0042] In this design, the dummy battery pack 2 is composed of multiple single cells that do not participate in the redox reaction. Structurally, it serves as a buffer for gas distribution and water management, without directly participating in the electrochemical reaction. This structure allows the liquid water, dispersed by the spiral device 4, to be preferentially dispersed and partially carried out within the dummy battery pack 2, thereby reducing the water impact and water load on the real battery pack 3 and helping to extend the lifespan of the single cells participating in the reaction.

[0043] In this embodiment, the thickness of the vented dummy battery pack 2 is less than the thickness of the real battery pack 3. By setting the thickness of the vented dummy battery pack 2 to be less than the thickness of the real battery pack 3, the necessary gas flow and moisture buffering capabilities are ensured while avoiding excessive occupation of the effective reaction space of the fuel cell stack. This structure is beneficial for balancing water management functions and power density requirements within a limited volume, enabling the cooperation between the spiral device 4 and the dummy battery pack to achieve effective dispersion of liquid water without significantly reducing the overall output performance of the fuel cell stack.

[0044] In the aforementioned hydrogen fuel cell stack 10, a spiral device 4 is installed at the hydrogen inlet 11 to effectively disperse and redistribute the liquid water entrained in the circulating hydrogen before it enters the stack. Under the guidance of the spiral, the liquid water is transformed into tiny water droplets and, propelled by the airflow, sequentially enters the hydrogen inlet channels of the dummy battery pack 2 and the real battery pack 3. This prevents liquid water from directly flooding a single cell in a concentrated flow. This structure significantly reduces the impact of concentrated liquid water discharge on the local electrochemical reactions and structural components of single cells under low electrical density conditions, allowing the liquid water to be carried out by multiple cells in a gentler, more dispersed manner. This improves the uniformity of hydrogen distribution within the stack, enhancing overall operational stability and durability.

[0045] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A hydrogen fuel cell stack, characterized in that, The fuel cell stack includes an inlet end plate, an inlet dummy battery pack, a real battery pack, and a spiral device. The inlet end plate, the inlet dummy battery pack, and the real battery pack are stacked sequentially. The internal structure of the fuel cell stack has a hydrogen flow channel. The hydrogen flow channel has a hydrogen inlet and a hydrogen outlet in a vertical direction on the surface of the inlet end plate. The spiral device is installed inside the hydrogen inlet. The inlet dummy battery pack has multiple first hydrogen inlet channels, and the real battery pack has multiple second hydrogen inlet channels. The hydrogen inlet intersects and communicates with the first and second hydrogen inlet channels. The hydrogen and liquid water mixture input from the hydrogen inlet is spirally guided by the spiral device, causing the liquid water in the mixture to be dispersed into water droplets and then sequentially enter the first and second hydrogen inlet channels, where it is dispersed and carried out by the airflow. The spiral device includes a main shaft, rotating guide vanes, and a fixed end plate. The rotating guide vanes are rotatably arranged along the main shaft, and the fixed end plate is connected to the rotating guide vanes. The edge of the hydrogen inlet is provided with a groove, and the fixed end plate is engaged in the groove. The main shaft coincides with the axis of symmetry of the hydrogen inlet. The hydrogen fuel cell stack is provided with an air circulation channel and a coolant circulation channel. The air circulation channel has an air inlet and an air outlet in the vertical direction on the surface of the air inlet end plate. The coolant circulation channel has a coolant inlet and a coolant outlet in the vertical direction on the surface of the air inlet end plate. The exhaust gas output from the air outlet, the coolant outlet and the hydrogen outlet enters the hydrogen inlet after liquid water is separated through the circulating hydrogen inlet common pipeline. The outlet of the circulating hydrogen inlet common pipeline is connected to the hydrogen inlet common pipeline, and the hydrogen inlet common pipeline is connected to the hydrogen inlet. The hydrogen containing liquid water output from the circulating hydrogen inlet common pipeline mixes with the dry hydrogen in the hydrogen inlet common pipeline to form the hydrogen and liquid water mixture, which then enters the hydrogen inlet.

2. The hydrogen fuel cell stack as described in claim 1, characterized in that, The main shaft, the rotating guide vane, and the fixed end plate are integrally formed, and the material of the spiral device includes polyphenylene sulfide.

3. The hydrogen fuel cell stack as described in claim 1, characterized in that, The outer diameter of the rotating guide vane along the main shaft is less than or equal to the inner diameter of the hydrogen inlet.

4. The hydrogen fuel cell stack as described in claim 1, characterized in that, The circulating hydrogen intake common pipeline includes a tail gas recovery pipeline, a gas-water separator and a hydrogen recovery pipeline connected in sequence. The gas-water separator is equipped with a liquid water discharge pipeline and the hydrogen recovery pipeline is equipped with a hydrogen circulation pump.

5. The hydrogen fuel cell stack as described in claim 4, characterized in that, The circulating hydrogen intake common pipeline includes a hydrogen tank and a hydrogen supply pipeline. The hydrogen tank is connected to the hydrogen inlet through the hydrogen supply pipeline, and the hydrogen recovery pipeline is connected to the hydrogen supply pipeline.

6. The hydrogen fuel cell stack as described in claim 1, characterized in that, The dummy battery pack consists of multiple single cells that do not participate in the redox reaction, while the real battery pack consists of multiple single cells that participate in the redox reaction.

7. The hydrogen fuel cell stack as described in claim 1, characterized in that, The thickness of the dummy battery pack is less than the thickness of the real battery pack.

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