Fuel cell system

Abstract

The utility model provides a kind of fuel cell system, including electric pile, air subsystem, hydrogen subsystem, cooling subsystem and tail exhaust water recycling subsystem;Cooling subsystem includes cooling circulation loop, heat dissipation module and cooling water tank;Tail exhaust water recycling subsystem includes water reservoir, tail exhaust water delivery line, and be equipped in tail exhaust water delivery line Humidification module, spray cooling module and water supplement module, water reservoir is communicated with the air tail exhaust end and hydrogen tail exhaust end of electric pile, Humidification module is connected to the air inlet end of air subsystem, for the air that is transported to electric pile is humidified;Spray cooling module is connected to the air inlet of heat dissipation module, for the spray cooling of heat dissipation module is carried out;Water supplement module is connected to cooling water tank, for to cooling water tank supplement tail exhaust recovery water.This application has realized the recycling of tail exhaust water, with efficient, reliable, energy saving, environmental protection and the advantages such as low operating cost.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a fuel cell system. Background Technology

[0002] A proton exchange membrane fuel cell (PEMFC) system is a highly efficient and clean energy conversion device. Its operation involves the coordinated work of multiple complex subsystems, including the supply of reactant gases (hydrogen and air), electrochemical reactions, heat management, and water management. Heat management and water management are among the key technologies affecting the performance, efficiency, and durability of fuel cells.

[0003] Existing fuel cell systems have the following problems in the integrated management of water and heat: (1) The proton exchange membrane needs to be kept moderately moist to maintain a high proton conductivity. Existing technologies generally equip the intake air with a humidification device, which not only increases the complexity of the system and parasitic power consumption, but also may introduce harmful ions if an external water source is used, contaminating the membrane electrode and damaging the stack life.

[0004] (2) A large amount of waste heat generated during system operation needs to be dissipated in a timely manner through the cooling system, especially under high temperature or high load conditions. The heat dissipation capacity directly determines the output stability and environmental adaptability of the system. In the existing technology, the cooling system usually relies on air cooling, but its heat dissipation efficiency is limited when the ambient temperature is high, which can easily lead to overheating of the fuel cell stack, forcing the system to operate at a reduced rate or even shut down for protection. Increasing the size of the heat sink to cope with the high temperature environment would contradict the requirements of system miniaturization and lightweighting.

[0005] (3) In the prior art, the cooling system is generally replenished periodically by external pure water, which not only increases the operation and maintenance costs and complexity, but also limits the system's ability to continue operating in scenarios where there is a lack of pure water supply facilities (such as remote areas and long-distance transportation). Utility Model Content

[0006] The purpose of this invention is to provide a fuel cell system that realizes the recycling of tailwater and has the advantages of high efficiency, reliability, energy saving, environmental protection and low operating cost.

[0007] To achieve the above objectives, the fuel cell system of this utility model includes a fuel cell stack, an air subsystem, a hydrogen subsystem, a cooling subsystem, and a tailrace wastewater recycling subsystem. The air subsystem is connected to the air input terminal of the fuel cell stack; the hydrogen subsystem is connected to the hydrogen input terminal of the fuel cell stack; the cooling subsystem includes a cooling circulation loop, a heat dissipation module, and a cooling water tank, the cooling circulation loop being connected to the cooling channels in the fuel cell stack, and the heat dissipation module and the cooling water tank being disposed on the cooling circulation loop; the tailrace wastewater recycling subsystem includes a water storage tank, a tailrace wastewater delivery pipeline, a humidification module, and a spray nozzle. The fuel cell stack includes a cooling module and a water replenishment module. The water storage tank is connected to the air exhaust port and hydrogen exhaust port of the fuel cell stack. The exhaust water delivery pipeline is connected to the water storage tank. The humidification module, the cooling module, and the water replenishment module are respectively located on the exhaust water delivery pipeline. The humidification module is connected to the air inlet of the air subsystem for humidifying the air supplied to the fuel cell stack. The cooling module is connected to the air inlet of the heat dissipation module for spray cooling of the heat dissipation module. The water replenishment module is connected to the cooling water tank for replenishing the cooling water tank with exhaust water.

[0008] Preferably, the water storage device includes a device body and a cavity structure. The upper part of the device body is provided with a tail discharge input end and a gas discharge end. The cavity structure is disposed within the device body and its two ends are respectively connected to the tail discharge input end and the gas discharge end. The tail discharge input end is connected to the air tail discharge end of the fuel cell stack. The cavity structure includes an expanded diameter silencing cavity. The expanded diameter silencing cavity extends from the tail discharge input end in a direction away from the tail discharge input end, and the cross-sectional area of ​​the expanded diameter silencing cavity gradually increases in the direction away from the tail discharge input end. The bottom of the expanded diameter silencing cavity is an inclined guide wall. The end of the inclined guide wall extends in a direction close to the bottom of the device body, and the cavity wall of the expanded diameter silencing cavity is distributed with multiple drainage micro-holes.

[0009] Preferably, the tailpipe input end is also connected to the hydrogen tailpipe end of the fuel cell stack, and the cavity structure further includes a gas guiding cavity, one end of which is connected to the end of the expanded diameter silencing cavity, and the other end of which is connected to the gas discharge end; the end portion of the inclined guiding wall and the wall of the gas guiding cavity are spaced apart to form a liquid channel.

[0010] Preferably, the water reservoir is provided with a plurality of baffles, at least two of the baffles are arranged sequentially on the top of the expanded diameter silencing cavity in a direction away from the tailpipe input end, and at least one of the baffles is provided on the bottom of the gas guiding cavity and close to the expanded diameter silencing cavity.

[0011] Preferably, the fuel cell system further includes a controller, a first liquid level sensor, and a water pump. The first liquid level sensor is disposed in the water storage tank, the water pump is disposed in the tail drain delivery pipeline, and the controller is connected to the first liquid level sensor, the water pump, the humidification module, the spray cooling module, and the water replenishment module.

[0012] Preferably, the humidification module includes a first tail drain delivery branch pipe, and a first solenoid valve, a first spray device, and a humidity sensor respectively connected to the controller. The humidity sensor is located on the air delivery pipe connecting the air subsystem and the fuel cell stack. The two ends of the first tail drain delivery branch pipe are respectively connected to the tail drain delivery pipe and the first spray device. The first solenoid valve is located on the first tail drain delivery branch pipe, and the nozzle of the first spray device is oriented towards the air inlet end.

[0013] Preferably, the spray cooling module includes a second tailwater conveying branch pipe, a second solenoid valve and a second spray device respectively connected to the controller. The two ends of the second tailwater conveying branch pipe are respectively connected to the tailwater conveying branch pipe and the second spray device. The second solenoid valve is located in the second tailwater conveying branch pipe, and the nozzle of the second spray device is arranged facing the air inlet of the heat dissipation module.

[0014] Preferably, the water replenishment module includes a third tailwater delivery branch pipe, a third solenoid valve and a second liquid level sensor respectively connected to the controller, the second liquid level sensor being disposed in the cooling water tank, the third solenoid valve being disposed in the third tailwater delivery branch pipe, and the two ends of the third tailwater delivery branch pipe being respectively connected to the tailwater delivery branch pipe and the cooling water tank.

[0015] Preferably, the tailwater recycling subsystem further includes a drainage module, which includes a drainage pipe, a first drainage valve and a third liquid level sensor respectively connected to the controller. The drainage pipe is connected to the drain outlet at the bottom of the water storage tank. The first drainage valve is located in the drainage pipe, and the third liquid level sensor is located in the water storage tank. The third liquid level sensor and the first liquid level sensor are located at different liquid level heights in the water storage tank. The third liquid level sensor is located near the top of the water storage tank, and the first liquid level sensor is located near the bottom of the water storage tank.

[0016] Preferably, the drainage module further includes a temperature sensor connected to the controller, the temperature sensor being located inside the water reservoir to detect the temperature of the liquid in the water reservoir.

[0017] Preferably, the drainage module further includes a conductivity sensor connected to the controller, the conductivity sensor being disposed inside the water reservoir for detecting the conductivity of the liquid in the water reservoir.

[0018] Preferably, the fuel cell system further includes an air exhaust control pipeline, which includes an air exhaust pipe and a back pressure valve. The two ends of the air exhaust pipe are respectively connected to the air exhaust end and the exhaust input end of the water storage device. The back pressure valve is located in the air exhaust pipe and connected to the controller.

[0019] Preferably, the fuel cell system further includes a hydrogen exhaust control pipeline, which includes a hydrogen exhaust pipeline, a water distributor, a circulation pump, a second drain valve, and an exhaust valve. The two ends of the hydrogen exhaust pipeline are connected to the hydrogen exhaust end and the water distributor, respectively. The drain end of the water distributor is connected to the exhaust input end of the water storage tank through a liquid discharge pipeline. The second drain valve is located in the liquid discharge pipeline. The exhaust end of the water distributor is connected to the hydrogen subsystem through a hydrogen circulation pipeline. The circulation pump is located in the hydrogen circulation pipeline, and the hydrogen circulation pipeline between the water distributor and the circulation pump is also connected to the exhaust input end through a gas exhaust pipeline. The exhaust valve is located in the gas exhaust pipeline. The water distributor is equipped with a fourth liquid level sensor. The fourth liquid level sensor, the circulation pump, the second drain valve, and the exhaust valve are all connected to the controller.

[0020] The beneficial effects of the fuel cell system described in this utility model are as follows: (1) This application utilizes the tailwater recovered in the water storage tank to self-humidify the air entering the fuel cell stack through a humidification module, which helps maintain the moisture of the proton exchange membrane. Moreover, this self-humidification mode can reduce or replace external humidification devices, simplifying the system and significantly improving system efficiency and performance. At the same time, directly using the high-purity tailwater generated by the fuel cell stack as the humidification water source effectively reduces the dependence on external water replenishment, strengthens the system's self-sustaining capability, and avoids damage to the proton exchange membrane from ionic contaminants (such as calcium, magnesium, and chloride ions) that may be introduced by using external water sources, which is conducive to achieving zero pollution and greatly extends the lifespan of the core components of the fuel cell stack.

[0021] (2) This application uses a spray cooling module to spray the wastewater recovered from the water storage tank onto the air inlet of the heat dissipation module (such as a radiator). This significantly improves the heat dissipation efficiency of the heat dissipation module by utilizing the principle that water evaporation on the surface of the heat sink absorbs a large amount of heat (i.e., evaporative heat absorption). This enhances the heat dissipation capacity of the cooling subsystem under high temperature and high load conditions, ensures the stability of operation in high temperature environments, and improves environmental adaptability. This allows the fuel cell system to operate stably in areas with higher ambient temperatures or in summer, avoiding power decay or shutdown protection due to insufficient heat dissipation. At the same time, due to the improved heat dissipation efficiency, it is possible to design a smaller heat dissipation module while achieving the same cooling effect, which helps to achieve system miniaturization and weight reduction.

[0022] (3) This application uses a water replenishment module to replenish the tailwater recovered in the water storage tank to the cooling water tank of the cooling subsystem, so that the water generated by the fuel cell reactor is collected and used to replenish the cooling subsystem to maintain the working temperature of the fuel cell reactor. This forms a benign internal water circulation, which can replenish the cooling water lost due to evaporation or slight leakage in a timely manner, maintain the pressure stability of the cooling circuit, prevent the cooling circuit from cavitation, local overheating and other problems caused by lack of cooling water, protect the cooling water pump and fuel cell, extend the life of core components, and enhance the reliability and durability of the system. Moreover, it greatly reduces the consumption and dependence on external pure water, significantly extends the continuous operation time of the system, and makes it suitable for application scenarios where there is a lack of pure water supply facilities (such as remote areas and long-distance freight).

[0023] (4) This application integrates the collection, storage, and distribution of tailwater generated by the fuel cell reactor into a unified tailwater recycling subsystem. This system simultaneously integrates the functions of replenishing water for the cooling subsystem, enhancing the cooling of the heat dissipation module, and humidifying the air at the air inlet of the air subsystem. This avoids the need to establish separate water sources for humidification, cooling, and replenishment, making the system structure more compact and improving the system integration. The recycling of the recycled water realizes the resource utilization of wastewater, achieving "zero wastewater discharge" (or near-zero discharge), saving energy consumption, and improving economic efficiency and environmental friendliness. Moreover, the tailwater generated by the fuel cell reactor is highly pure. Using this recycled tailwater for humidification and replenishment of water for the cooling subsystem can effectively prevent ion contamination that may be caused by using water of unknown quality from external sources, protect the sensitive proton exchange membrane and cooling channels, and avoid performance degradation and corrosion caused by impurities. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a fuel cell system according to an embodiment of the present invention.

[0025] Figure 2 This is a connection diagram of a portion of the structure of the fuel cell system according to an embodiment of the present invention.

[0026] Explanation of reference numerals in the attached figures: 1. Fuel cell stack; 2. Air subsystem; 21. Air inlet; 3. Hydrogen subsystem; 31. Hydrogen supply module; 4. Cooling circulation loop; 41. Heat dissipation module; 42. Cooling water tank; 43. Cooling water pump; 5. Water storage tank; 501. Device body; 502. Expanded diameter silencer cavity; 503. Gas guide cavity; 504. Tail exhaust inlet; 505. Gas exhaust outlet; 506. Inclined guide wall; 507. Drainage micropores; 508. Baffle; 51. Tail exhaust delivery pipeline; 52. Humidification module; 521. First tail exhaust delivery branch pipeline; 522. First solenoid valve; 523. First spray device; 524. Humidity sensor; 53. Spray cooling module; 531. Second tail exhaust delivery branch pipeline; 532. Second solenoid valve; 533. Second spray device; 54. Water replenishment module; 541. Third tail drain delivery branch pipe; 542. Third solenoid valve; 543. Second liquid level sensor; 55. First liquid level sensor; 56. Water pump; 57. Drainage pipe; 58. First drain valve; 59. Third liquid level sensor; 510. Temperature sensor; 511. Conductivity sensor; 512. Tail gas treatment device; 6. Air tail exhaust pipe; 61. Back pressure valve; 7. Hydrogen tail exhaust pipe; 71. Water distributor; 72. Circulation pump; 73. Second drain valve; 74. Exhaust valve; 75. Liquid discharge pipe; 76. Hydrogen circulation pipe; 77. Gas discharge pipe; 78. Fourth liquid level sensor; 8. Controller. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this utility model pertains. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed following the word and its equivalents, but does not exclude other elements or objects.

[0028] To overcome the problems existing in the prior art, this utility model provides a fuel cell system that realizes the recycling of tailwater and has the advantages of high efficiency, reliability, energy saving, environmental protection and low operating cost.

[0029] In some embodiments of this utility model, reference is made to Figure 1 and Figure 2 The fuel cell system includes a stack 1, an air subsystem 2, a hydrogen subsystem 3, a cooling subsystem (not shown in the figure), and a tailwater recycling subsystem (not shown in the figure). The air subsystem 2 is connected to the air input terminal of the stack 1; the hydrogen subsystem 3 is connected to the hydrogen input terminal of the stack 1; the cooling subsystem includes a cooling circulation loop 4, a heat dissipation module 41, and a cooling water tank 42. The cooling circulation loop 4 is connected to the cooling channels in the stack 1, and the heat dissipation module 41 and the cooling water tank 42 are located on the cooling circulation loop 4; the tailwater recycling subsystem includes a water storage tank 5, a tailwater delivery pipeline 51, a humidification module 52, and a spray cooling module. The water storage module 5 is connected to the air exhaust end and hydrogen exhaust end of the fuel cell stack 1. The exhaust water delivery pipeline 51 is connected to the water storage module 5. The humidification module 52, the spray cooling module 53, and the water replenishment module 54 are respectively installed on the exhaust water delivery pipeline 51. The humidification module 52 is connected to the air inlet end 21 of the air subsystem 2 to humidify the air delivered to the fuel cell stack 1. The spray cooling module 53 is connected to the air inlet of the heat dissipation module 41 to spray and cool the heat dissipation module 41. The water replenishment module 54 is connected to the cooling water tank 42 to replenish the exhaust water to the cooling water tank 42.

[0030] The proton exchange membrane in fuel cell stack 1 needs to be kept moist to efficiently conduct protons. This application utilizes the wastewater recovered from the water storage tank 5 via the humidification module 52 to self-humidify the air entering fuel cell stack 1, which helps maintain the moisture of the proton exchange membrane. Furthermore, this self-humidification mode can reduce or replace external humidification devices, simplifying the system and significantly improving system efficiency and performance. Simultaneously, directly using the high-purity wastewater generated by fuel cell stack 1 as the humidification water source effectively reduces dependence on external water replenishment, strengthens the system's self-sustaining capability, and avoids damage to the proton exchange membrane from ionic contaminants (such as calcium, magnesium, and chloride ions) that may be introduced by using external water sources, thus achieving zero pollution and greatly extending the lifespan of the core components of fuel cell stack 1.

[0031] This application utilizes a spray cooling module 53 to spray the wastewater recovered from the water storage tank 5 onto the air inlet of the heat dissipation module 41 (such as a radiator). This significantly improves the heat dissipation efficiency of the heat dissipation module 41 by utilizing the principle that water evaporation on the surface of the heat sink absorbs a large amount of heat (i.e., evaporative heat absorption). This enhances the heat dissipation capacity of the cooling subsystem under high-temperature and high-load conditions, ensures operational stability in high-temperature environments, and improves environmental adaptability. It enables the fuel cell system to operate stably in areas with higher ambient temperatures or during summer, avoiding power decay or shutdown protection due to insufficient heat dissipation. Furthermore, due to the improved heat dissipation efficiency, it is possible to design a smaller heat dissipation module while achieving the same cooling effect, contributing to the miniaturization and weight reduction of the system.

[0032] This application uses a water replenishment module 54 to replenish the tailwater recovered from the water storage tank 5 to the cooling water tank 42 of the cooling subsystem. This allows the water produced by the reaction of the fuel cell stack 1 to be collected and then used to replenish the cooling subsystem that maintains the operating temperature of the fuel cell stack 1. This forms a virtuous cycle of internal water, which can replenish the cooling water lost due to evaporation or minor leakage in a timely manner, maintain the pressure stability of the cooling circuit, and prevent problems such as cavitation and local overheating caused by lack of cooling water in the cooling circuit. This protects the cooling water pump 43 and the fuel cell stack 1, extends the life of core components, and enhances the reliability and durability of the system. Moreover, it greatly reduces the consumption and dependence on external pure water, significantly extends the continuous operation time of the system, and makes it suitable for application scenarios where there is a lack of pure water supply facilities (such as remote areas and long-distance freight).

[0033] This application connects the water storage device 5 to the air exhaust terminal and hydrogen exhaust terminal of the fuel cell stack 1, and the tailwater delivery pipeline 51 is connected to the water storage device 5. The humidification module 52, the spray cooling module 53, and the water replenishment module 54 are respectively installed on the tailwater delivery pipeline 51. This integrates the collection, storage, and distribution of tailwater generated by the reaction of the fuel cell stack 1 into a unified tailwater recycling subsystem. This allows the system to simultaneously integrate the functions of replenishing water for the cooling subsystem, enhancing the cooling of the heat dissipation module 41, and humidifying the air at the air inlet terminal 21 of the air subsystem 2. This avoids the need to establish separate water sources for humidification, cooling, and water replenishment, making the system structure more compact and improving the system integration. The recycling of the recovered water realizes the resource utilization of wastewater, achieving "zero wastewater discharge" (or near-zero discharge), saving energy consumption, and improving economic efficiency and environmental friendliness. Moreover, the tailwater generated by fuel cell stack 1 is highly pure. Using this recycled tailwater for humidification and water replenishment to the cooling subsystem can effectively prevent ion contamination that may be caused by using water of unknown quality from external sources, protect sensitive proton exchange membranes and cooling channels, and avoid performance degradation and corrosion caused by impurities.

[0034] In some embodiments of this utility model, reference is made to Figure 1 and Figure 2 The fuel cell system further includes a controller 8, a first liquid level sensor 55, and a water pump 56. The first liquid level sensor 55 is located in the water storage tank 5, and the water pump 56 is located in the tail drain delivery pipeline 51. The water pump 56 can pump the recycled water stored in the water storage tank 5 to the humidification module 52, the spray cooling module 53, and the water replenishment module 54 for air humidification, cooling of the heat dissipation module 41, and replenishment of cooling water required by the cooling subsystem. The controller 8 is connected to the first liquid level sensor 55, the water pump 56, the humidification module 52, and the water replenishment module 54. The spray cooling module 53 is connected to the water replenishment module 54, allowing the water pump 56, the humidification module 52, the spray cooling module 53, and the water replenishment module 54 to be started or stopped under the control of the controller 8 according to real-time needs. This achieves optimal allocation of water resources, which helps reduce the energy consumption of the tailwater recycling subsystem itself, thereby improving the net output power and overall energy efficiency of the fuel cell system, reducing unnecessary mechanical wear and electrical operating time, extending component life, reducing long-term maintenance costs, and significantly improving the overall stability and reliability of the system.

[0035] In this embodiment, the first liquid level sensor 55 is used to monitor the real-time water level information in the water storage tank 5 and transmit it to the controller 8. The controller 8 dynamically adjusts the water pump 56, humidification module 52, spray cooling module 53, and water replenishment module 54 based on the real-time water level information from the first liquid level sensor 55 and the real-time needs of the humidification module 52, spray cooling module 53, and water replenishment module 54 (and can also be based on the operating status of the fuel cell stack 1, such as power, temperature, and environmental parameters). Specifically, when the first liquid level sensor 55 detects that the water storage in the water storage tank 5 is limited, the controller 8 can prioritize ensuring the most critical needs based on the operating conditions. For example, in a high-temperature environment, the spray cooling module 53 is activated first to ensure heat dissipation and cooling of the heat dissipation module 41; in a dry environment, the humidification module 52 is activated first to maintain the humidity of the air supplied to the fuel cell stack 1; and when the water level in the cooling water tank 42 is low, water is replenished first. This embodiment enhances the system's adaptability, significantly expanding the applicable geographical and climatic range of the fuel cell system. Furthermore, through the coordination of controller 8, it prevents disorderly resource competition among water-using modules in the tailrace wastewater recycling subsystem, ensuring precise and efficient water resource allocation under any operating condition, far exceeding fixed-ratio or manual allocation modes, and avoiding ineffective or conflicting operation. Simultaneously, this embodiment facilitates response to dynamic load changes. For example, when the load on stack 1 suddenly increases, controller 8 can simultaneously increase the intensity of humidified air supplied to stack 1 and the intensity of spray cooling, quickly suppressing temperature rise, avoiding performance fluctuations, and making the system output more stable and responsive. In other words, the fuel cell system of this application can automatically adapt to changes in the external environment and internal load fluctuations. Moreover, controller 8 can control the start and stop of water pump 56 by monitoring the real-time water level information in the water storage tank 5, thereby effectively preventing the water pump 56 from running dry and being damaged.

[0036] In some embodiments of this utility model, the controller 8 is provided with a minimum protection water level threshold for the water tank 5, so that secondary water use functions are suspended when the water level is too low. For example, when the water level in the water tank 5 is too low, the spray cooling of the heat dissipation module 41 can be suspended to ensure that the air humidification or cooling subsystem of the core fuel cell stack 1 is continuously replenished with water, thereby directly protecting the performance and lifespan of the fuel cell stack 1.

[0037] In some embodiments of this utility model, reference is made to Figure 1The humidification module 52 includes a first tail drain delivery branch pipe 521, a first solenoid valve 522, a first spray device 523, and a humidity sensor 524, which are respectively connected to the controller 8. The humidity sensor 524 is located on the air delivery pipe connecting the air subsystem 2 and the fuel cell stack 1. The two ends of the first tail drain delivery branch pipe 521 are respectively connected to the tail drain delivery branch pipe 51 and the first spray device 523. The first solenoid valve 522 is located on the first tail drain delivery branch pipe 521. The nozzle of the first spray device 523 is set towards the air inlet end 21 for humidifying the air entering the air inlet end 21.

[0038] In this embodiment, the humidity sensor 524 monitors the humidity information of the air entering the fuel cell stack 1 in real time and feeds it back to the controller 8. This allows the controller 8 to dynamically adjust the opening degree or start / stop frequency of the first solenoid valve 522 based on the humidity information, avoiding insufficient or excessive humidification of the air entering the fuel cell stack 1. This precise control eliminates the problems of insufficient humidification leading to dryness of the proton exchange membrane and increased resistance, and also prevents excessive humidification from causing the fuel cell stack 1 to be "flooded" and obstructing gas transmission. This improves the output performance, efficiency, and stability of the fuel cell stack 1, ensuring that the fuel cell stack 1 can obtain reaction gas with suitable humidity in any environment (dry winter or humid summer), thus enhancing the environmental adaptability and reliability of the system.

[0039] In this embodiment, the first spray device 523 atomizes the recovered water into micron-sized droplets, which are then directly sprayed into the airflow at the air inlet 21. This fully utilizes the principle that water mist has a large specific surface area, enabling rapid evaporation and absorption of sensible heat from the air (isenthalpic humidification), thus eliminating the need for additional heating energy consumption. This is more energy-efficient than humidification methods that require an external heat source (such as steam humidification) and offers higher humidification efficiency. Furthermore, the combination of the first solenoid valve 522 and the first spray device 523 allows for rapid opening and closing based on control commands, achieving a millisecond to second-level response to humidity changes, which is beneficial for handling rapid fluctuations in the load of the fuel cell stack 1. Simultaneously, the humidification module 52 has a simple and compact structure. Compared to complex devices such as external humidifiers, the spray-type humidification module 52 in this embodiment has a simpler structure and is easier to integrate into the air duct, reducing cost and system complexity.

[0040] In this embodiment, the humidification module 52, by setting a first tailwater delivery branch pipe 521 and a first solenoid valve 522, enables the controller 8 to independently adjust or temporarily shut off the water supply of the humidification branch according to the humidification demand and the water level of the water tank 5, ensuring that the core functions of the system are prioritized under limited recycled water conditions. Moreover, the independent branch and valve design ensures that the start-up, shutdown and flow regulation of the humidification module 52 will not directly impact the water pressure and flow of the spray cooling module 53 and the water replenishment module 54, avoiding interference between modules and improving the independence and overall stability of the operation of each water-using module in the tailwater recycling subsystem.

[0041] In some embodiments, the controller 8 can compare the humidity information with a preset optimal humidity threshold to determine the opening degree or start-stop frequency of the first solenoid valve 522. The controller 8 adjusting the opening degree or start-stop frequency of the first solenoid valve 522 according to the humidity information is a conventional technique in the art and will not be described in detail here.

[0042] In some specific embodiments, during the operation of the fuel cell, when the controller 8 receives a high real-time water level in the water tank 5 as monitored by the first liquid level sensor 55, and the humidity sensor 524 detects that the air humidity is low, the controller 8 controls the opening of the first solenoid valve 522 to pump the recycled water in the water tank 5 to the first spray device 523 through the tail drain delivery pipeline 51 and the first tail drain delivery branch pipeline 521, so as to perform spray humidification operation on the air inlet end 21 of the air subsystem 2.

[0043] In some embodiments of this utility model, reference is made to Figure 1 The spray cooling module 53 includes a second tail drain delivery branch pipe 531, a second solenoid valve 532 and a second spray device 533 respectively connected to the controller 8. The two ends of the second tail drain delivery branch pipe 531 are respectively connected to the tail drain delivery branch pipe 51 and the second spray device 533. The second solenoid valve 532 is located in the second tail drain delivery branch pipe 531. The nozzle of the second spray device 533 is arranged facing the air inlet of the heat dissipation module 41 for spray cooling of the heat dissipation module 41.

[0044] The heat dissipation module 41 contains high-temperature coolant flowing from the cooling cycle of the fuel cell stack 1. Its function is to dissipate this heat into the air via a fan. This embodiment employs a second spray device 533 to achieve intelligent spraying. Tiny droplets are evenly sprayed onto the fins of the heat dissipation module 41 (typically a radiator or condenser) in the cooling subsystem. When the droplets contact the high-temperature fins, they instantly evaporate, absorbing a large amount of heat from the fins, greatly enhancing the heat dissipation capacity of the heat dissipation module 41 to the external environment. Even under high ambient temperatures or heavy fuel cell operation, it effectively maintains the operating temperature of the fuel cell stack 1 within the optimal range. This achieves a reduction or replacement of the enormous fan power consumption required to achieve the same cooling effect with minimal water consumption, reducing parasitic power consumption, improving net output, and ultimately enhancing the system's net output power and overall efficiency. Furthermore, the water consumed by the spray cooling in this embodiment is the system's own recycled tailwater, achieving internal water resource circulation. This eliminates or reduces the need for external water replenishment, resulting in extremely low costs and achieving dual optimization of resources and energy efficiency.

[0045] This embodiment effectively reduces the air temperature flowing through the heat dissipation module 41 (i.e., lowers its inlet air temperature) through active spray cooling, thereby significantly increasing the heat exchange temperature difference and heat exchange capacity within the same heat dissipation area. In other words, the spray cooling module 53 provides additional and robust heat dissipation margin, allowing for the use of smaller heat dissipation modules 41 (radiators, fans) in the initial design phase. This contributes to system weight reduction, miniaturization, and cost reduction. Furthermore, it enables the fuel cell system to maintain rated power output in hot climates or high-temperature conditions, avoiding performance degradation or thermal protection shutdowns due to insufficient heat dissipation. This enhances its high-temperature operating capability, broadens the system's application area and seasonal range, and improves its environmental adaptability.

[0046] In this embodiment, the controller 8 can precisely control the opening and closing of the second solenoid valve 532 as needed, thereby adjusting the intensity of the cooling water mist sprayed by the second spray device 533 onto the air inlet of the heat dissipation module 41. This allows the water mist to evaporate on the surface of the heat sink or in the airflow (utilizing the principle that the latent heat of vaporization of water absorbs a large amount of heat). Its cooling capacity far exceeds that of simple air cooling, significantly improving heat dissipation efficiency. It can quickly dissipate heat under extreme conditions, preventing the fuel cell stack 1 from overheating. Unlike traditional continuous spraying or fixed modes, this embodiment uses the second solenoid valve 532 and the controller 8 to activate only when the heat dissipation demand is high, achieving intelligent dynamic control that starts on demand. This precisely matches the heat load, avoids unnecessary water and power consumption, and perfectly matches the heat dissipation capacity with actual needs.

[0047] In this embodiment, the spray cooling module 53, through the second tail drain delivery branch pipe 531 and the second solenoid valve 532, enables the controller 8 to independently adjust or temporarily shut off the water supply of the spray cooling branch according to the heat dissipation requirements and the water level of the water tank 5, ensuring that the core functions of the system are prioritized under limited recycled water conditions; moreover, the independent branch and valve design avoids water circuit interference with the humidification module 52 and the water replenishment module 54, and the controller 8 can perform precise and rapid independent control, improving the control accuracy and stability of the entire water circulation subsystem.

[0048] In some specific embodiments, during the operation of the fuel cell, when the controller 8 receives a high real-time water level in the water tank 5 as monitored by the first liquid level sensor 55, and the heat dissipation module 41 is cooling down, the controller 8 controls the opening of the second solenoid valve 532 to pump the recycled water in the water tank 5 through the tail drain delivery pipeline 51 and the second tail drain delivery branch pipeline 531 to the second spray device 533 to perform spray cooling operation on the heat dissipation module 41.

[0049] In some embodiments of this utility model, reference is made to Figure 1 The water replenishment module 54 includes a third tailwater conveying branch pipe 541, a third solenoid valve 542 and a second liquid level sensor 543 respectively connected to the controller 8. The second liquid level sensor 543 is disposed in the cooling water tank 42. The third solenoid valve 542 is disposed in the third tailwater conveying branch pipe 541. The two ends of the third tailwater conveying branch pipe 541 are respectively connected to the tailwater conveying pipe 51 and the cooling water tank 42 for replenishing the cooling water tank 42 with tailwater recovery water.

[0050] In this embodiment, the second liquid level sensor 543 monitors the water level information of the cooling water tank 42 in real time and feeds it back to the controller 8. The controller 8 then precisely controls the opening and closing of the third solenoid valve 542 according to requirements (such as a preset water level threshold). This allows for the automatic and timely replenishment of cooling water lost in the cooling subsystem due to evaporation and seepage, ensuring that the cooling circuit is always full of cooling water. This fundamentally prevents faults such as local overheating of the fuel cell stack 1, reduced heat dissipation efficiency, or even burnout caused by insufficient cooling water, greatly improving the reliability and durability of the system. Moreover, the system can maintain the water balance of the cooling subsystem for a long time without manual intervention, enhancing the automation level and applicability of the system, making it particularly suitable for applications requiring remote or long-term continuous operation.

[0051] In this embodiment, the cooling water tank 42 itself is a water storage unit, storing water when production is abundant and providing support during peak water usage periods. Furthermore, combined with the first liquid level sensor 55 and the second liquid level sensor 543, the controller 8 can intelligently decide on water resource allocation based on the water level in the cooling water tank 42 (monitored by the second liquid level sensor 543) and the total water level in the water storage tank 5 (monitored by the first liquid level sensor 55). For example, when the cooling water tank 42 is insufficient, priority can be given to ensuring the basic water replenishment needs of the cooling subsystem (related to safety), while moderately limiting the water used for spray cooling (related to performance), thereby maximizing resource utilization efficiency while ensuring the safe operation of the system.

[0052] In this embodiment, high-purity distilled water generated by the chemical reaction of fuel cell stack 1 is directly used as makeup water for the cooling system. This not only ensures the stability of key parameters such as the conductivity of the cooling water in the cooling circulation loop 4, avoiding the introduction of impurity ions that could affect system insulation or cause parasitic currents, thus protecting fuel cell stack 1 and sensitive electrical components, but also helps reduce or avoid scaling and corrosion, extending the lifespan of the cooling subsystem. It solves the problem that traditional makeup water containing minerals is prone to scaling in pipes and heat dissipation modules 41 over long-term operation, affecting heat dissipation and potentially causing corrosion. This module allows the wastewater generated by fuel cell stack 1 to be collected and ultimately used in the circulation system to maintain the operating temperature (cooling) of fuel cell stack 1, forming a complete internal loop. This greatly reduces dependence on external water sources, significantly lowers operating and maintenance costs and infrastructure dependence, achieving true "zero wastewater discharge." The makeup water module 54, combined with the humidification module 52 and the spray cooling module 53, allows almost all the water generated by fuel cell stack 1 to be effectively reused by the system itself, resulting in significant environmental benefits and meeting the requirements of a green energy system.

[0053] In some specific embodiments, water replenishment judgment and execution are initiated after the fuel cell system shutdown and purging phase is completed to ensure that the operation does not affect the normal power generation operation of the fuel cell. Specifically, when the controller 8 receives a high real-time water level in the water storage tank 5 monitored by the first liquid level sensor 55, and a low real-time water level in the cooling water tank 42 monitored by the second liquid level sensor 543, the controller 8 controls the opening of the third solenoid valve 542 to pump the recovered water in the water storage tank 5 into the cooling water tank 42 through the tail drain delivery pipeline 51 and the third tail drain delivery branch pipeline 541 for water replenishment.

[0054] In some embodiments of this utility model, reference is made to Figure 1The tailwater recycling subsystem further includes a drainage module, which includes a drainage pipe 57, a first drainage valve 58 and a third liquid level sensor 59 connected to the controller 8, respectively. The drainage pipe 57 is connected to the drain outlet at the bottom of the water storage tank 5. The first drainage valve 58 is located on the drainage pipe 57. The third liquid level sensor 59 is located on the water storage tank 5, and the third liquid level sensor 59 and the first liquid level sensor 55 are located at different liquid level heights in the water storage tank 5. The third liquid level sensor 59 is located near the top of the water storage tank 5, and the first liquid level sensor 55 is located near the bottom of the water storage tank 5.

[0055] In this embodiment, a first liquid level sensor 55 is installed near the bottom of the water storage tank 5 to control the water supply of the humidification module 52, the spray cooling module 53, and the water replenishment module 54. A third liquid level sensor 59 is added near the top of the water storage tank 5. When the water level rises abnormally and touches the third liquid level sensor 59 at the top, the controller 8 can immediately trigger an alarm and open the first drain valve 58 for emergency drainage. This avoids electrical short circuits, component corrosion, or system failures caused by the water supply modules such as the humidification module 52, the spray cooling module 53, and the water replenishment module 54 overflowing due to excessive instantaneous water production or accidental shutdown of the water-using modules, thus greatly improving the safety and reliability of the system. Furthermore, the liquid level in the water tank 5 can be divided into a low-level zone, a normal operating zone, and a high-level warning zone by the first liquid level sensor 55 (low level) and the third liquid level sensor 59 (high level), allowing the controller 8 to implement differentiated strategies based on different liquid level zones. For example, when the water level in the water tank 5 is detected to be in the low-level zone, non-core water use such as the spray cooling module 53 can be restricted or shut down, prioritizing the needs of the humidification module 52 and the water replenishment module 54. When the water level in the water tank 5 is detected to be in the normal operating zone, the spray cooling module 53, the humidification module 52, and the water replenishment module 54 can be intelligently allocated as needed. When the water level in the water tank 5 is detected to be in the high-level warning zone, the spray cooling module 53 can be actively activated to enhance heat dissipation (even if the heat dissipation demand is not high) to consume water, or an alarm can be issued to prompt whether to actively drain water through the drainage pipe 57. If the water level continues to rise to a dangerous level, the drainage pipe 57 will be activated for emergency drainage. Precise liquid level zoning information helps the controller 8 optimize the start-up, shutdown, and operating frequency of the water pump 56, preventing the water pump 56 from running dry at extremely low liquid levels or continuously operating in ineffective high liquid level ranges. This extends the lifespan of the water pump 56, reduces parasitic power consumption, and gives the system the ability to self-regulate and recover under extreme or abnormal operating conditions. If the solenoid valve of the water replenishment module 54 fails to open, or the spray cooling module 53 is blocked, causing poor water supply, the water level in the water tank 5 will rise abnormally. At this time, the drainage module can serve as a final guarantee, preventing the entire water management system from collapsing due to local failures, buying time for fault diagnosis and maintenance, and enhancing the system's robustness and environmental adaptability in the face of abnormal operating conditions.

[0056] Furthermore, in this embodiment, the controller 8 can actively control the opening of the first drain valve 58, draining all or part of the water in the water tank 5 through the drain pipe 57. This allows for the one-click emptying of all pipes and the water tank 5 before the system needs to be shut down for an extended period (especially in cold environments), completely preventing equipment damage caused by the expansion of frozen residual water. This achieves both system emptying and winter freeze protection. Moreover, even after long-term system operation, although the water quality is pure, there may still be trace amounts of impurities deposited. Regularly flushing and emptying the water tank 5 facilitates maintenance, keeps the water circulation system clean, and improves long-term operational reliability.

[0057] In some embodiments of this utility model, reference is made to Figure 1 The drainage module also includes a temperature sensor 510 connected to the controller 8. The temperature sensor 510 is located inside the water reservoir 5 to detect the temperature of the liquid in the water reservoir 5. When the temperature sensor 510 detects that the liquid temperature in the water reservoir 5 is too low, the controller 8 can control the first drain valve 58 to actively drain the water stored in the water reservoir 5, so as to prevent the water stored in the water reservoir 5 from freezing in the low temperature environment.

[0058] In some embodiments of this utility model, reference is made to Figure 1 The drainage module also includes a conductivity sensor 511 connected to the controller 8. The conductivity sensor 511 is located inside the water tank 5 to detect the conductivity of the liquid in the water tank 5. When the conductivity sensor 511 detects that the conductivity of the water stored in the water tank 5 is too high (water with high conductivity is not suitable as water for replenishing the cooling water tank 42 and for air humidification), the controller 8 can control the first drain valve 58 to actively drain the water stored in the water tank 5.

[0059] In some embodiments of this utility model, reference is made to Figure 1 The fuel cell system also includes an air exhaust control pipeline, which comprises an air exhaust pipe 6 and a back pressure valve 61. The two ends of the air exhaust pipe 6 are connected to the air exhaust end and the exhaust input end 504 of the water storage tank 5, respectively. This allows humid exhaust gas rich in water vapor to be directly guided from the fuel cell stack 1 through the exhaust input end 504 to the water storage tank 5 via the air exhaust pipe 6, ensuring exhaust water recovery. The back pressure valve 61 is located in the air exhaust pipe 6 and connected to the controller 8, enabling precise maintenance of the air side pressure of the fuel cell stack 1. This significantly increases the oxygen partial pressure and reactant gas concentration, thereby improving the voltage output and power density of the fuel cell stack 1. Furthermore, appropriate back pressure helps to discharge unreacted air and liquid water produced in the reaction within the fuel cell stack 1 into the water storage tank 5 via the back pressure valve 61, preventing cathode flooding and ensuring smooth oxygen diffusion to the catalyst surface. This guarantees stable operation of the fuel cell stack 1 under high current density, improving its performance and efficiency.

[0060] In some embodiments of this utility model, reference is made to Figure 1The fuel cell system further includes a hydrogen exhaust control pipeline, which includes a hydrogen exhaust pipeline 7, a water distributor 71, a circulation pump 72, a second drain valve 73, and an exhaust valve 74. The two ends of the hydrogen exhaust pipeline 7 are connected to the hydrogen exhaust end and the water distributor 71, respectively. The drain end of the water distributor 71 is connected to the exhaust inlet 504 of the water storage tank 5 via a liquid discharge pipeline 75. The second drain valve 73 is located in the liquid discharge pipeline 75. The exhaust end of the water distributor 71 is connected to the hydrogen circulation pump 74. The loop 76 is connected to the hydrogen subsystem 3. The circulation pump 72 is located in the hydrogen circulation loop 76. The hydrogen circulation loop 76 between the water distributor 71 and the circulation pump 72 is also connected to the tail discharge input terminal 504 through the gas discharge loop 77. The exhaust valve 74 is located in the gas discharge loop 77. The water distributor 71 is equipped with a fourth liquid level sensor 78. The fourth liquid level sensor 78, the circulation pump 72, the second drain valve 73, and the exhaust valve 74 are all connected to the controller 8.

[0061] In this embodiment, unreacted hydrogen from the anode outlet of fuel cell stack 1 is repressurized and transported back to hydrogen subsystem 3 to mix with fresh hydrogen through water separator 71, hydrogen circulation pipeline 76, and circulation pump 72, achieving active recovery and recycling of unreacted hydrogen and significantly improving fuel economy. Water generated at the anode of fuel cell stack 1 is discharged with the tail hydrogen and undergoes efficient gas-liquid separation through water separator 71. The controller, based on the liquid level information within water separator 71 fed back by the fourth liquid level sensor 78, controls the opening and closing of the second drain valve 73, effectively guiding the separated liquid water through liquid discharge pipeline 75 (controlled by the second drain valve 73) into the water storage tank 5. This achieves effective separation and recovery of water generated on the hydrogen side, further increasing the supply of circulating water resources within the system, reducing dependence on external water replenishment. Furthermore, the efficient water separation through water separator 71 prevents liquid water from being carried into circulation pump 72 or re-entering fuel cell stack 1, protecting circulation pump 72 and preventing anode flooding, thus ensuring the reliability of system operation.

[0062] During operation of fuel cell stack 1, nitrogen gas in the air permeates through the proton exchange membrane to the anode side. Long-term circulation leads to nitrogen accumulation, diluting the hydrogen concentration. In this embodiment, a gas discharge pipe 77 leading to the tailpipe input 504 is provided on the hydrogen circulation pipe 76 between the water distributor 71 and the circulation pump 72, and controlled by an exhaust valve 74. This allows the exhaust valve 74 to be opened periodically or as needed, thereby discharging the mixed gas rich in nitrogen and other impurities. This maintains sufficient purity of the circulating hydrogen, ensuring the performance of fuel cell stack 1. Moreover, the gas discharge pipe 77 and the exhaust valve 74 constitute a controlled and safe discharge port, enabling safe gas discharge during system startup, shutdown, or malfunction, preventing the accumulation of hazardous gases within the system.

[0063] In some embodiments of this utility model, reference is made to Figure 1 The fuel cell system also includes a hydrogen supply module 31, through which the fuel cell system supplies hydrogen to the fuel cell stack 1.

[0064] In some embodiments of this utility model, reference is made to Figure 1 The cooling subsystem also includes a cooling water pump 43, which is located in the cooling circulation loop 4 and is situated between the heat dissipation module 41 and the cooling water tank 42. The cooling water tank 42 replenishes cooling water to the inlet end of the cooling water pump 43.

[0065] In some embodiments of this utility model, the functional modules included in the air subsystem 2 and the hydrogen subsystem 3 are conventional configurations in the art and will not be described again here.

[0066] In some embodiments of this utility model, reference is made to Figure 1 The water storage device 5 includes a device body 501 and a cavity structure. The upper symmetrical side of the device body 501 is provided with a tail discharge input end 504 and a gas discharge end 505. The cavity structure is located inside the device body 501 and its two ends are respectively connected to the tail discharge input end 504 and the gas discharge end 505. The tail discharge input end 504 is connected to the air tail discharge end of the fuel cell stack 1. The cavity structure includes an expanded diameter silencing cavity 502. The expanded diameter silencing cavity 502 extends from the tail discharge input end 504 in a direction away from the tail discharge input end 504, and the cross-sectional area of ​​the expanded diameter silencing cavity 502 gradually increases in the direction away from the tail discharge input end 504. The bottom of the expanded diameter silencing cavity 502 is an inclined guide wall 506. The end of the inclined guide wall 506 extends in a direction close to the bottom of the device body 501, and the cavity wall of the expanded diameter silencing cavity 502 is distributed with a plurality of drainage microholes 507.

[0067] In this embodiment, the cross-sectional area of ​​the expanded-diameter silencer cavity 502 gradually increases along the airflow direction, forming an expansion-type silencer structure. This causes a sharp drop in airflow velocity when the high-temperature, high-pressure exhaust humid air from the exhaust terminal of the fuel cell stack 1 enters the expanded-diameter silencer cavity 502 from the exhaust input terminal 504. This effectively attenuates low- and mid-frequency exhaust noise, achieving highly efficient passive silencing and significantly reducing system operating noise. Moreover, this silencing function is entirely achieved by the ingenious expanded-diameter silencer cavity 502, requiring no additional active noise reduction equipment or energy consumption, thus achieving passive noise reduction and zero energy consumption while maintaining the system's energy efficiency advantage. The expanded-diameter structure of the expanded-diameter silencer cavity 502, while reducing airflow velocity, also extends the residence time of the gas within the cavity, allowing water vapor in the exhaust gas more time to contact the relatively low-temperature cavity wall, thereby maximizing condensation and precipitation, and improving the recovery of exhaust wastewater.

[0068] In this embodiment, the inclined guide wall 506 helps to guide the condensate flow away from the high-speed airflow zone quickly and allows it to flow smoothly along the inclined guide wall 506 to the bottom of the device body 501 for storage. At the same time, the condensate can also enter the water collection area of ​​the device body 501 through the drainage micro-holes 507, effectively preventing the condensate from being blown away by the high-speed airflow to form mist and be carried out, effectively preventing secondary entrainment and blockage, and ensuring reliable condensate recovery. Moreover, the inclined design of the inclined guide wall 506 makes it less likely to form dead corners for water accumulation, reducing the risk of sedimentation and blockage, and improving the long-term operational reliability of the device.

[0069] In this application, the end portion of the inclined guide wall 506 is the end portion of the inclined guide wall 506 that is away from the tailpipe input end 504.

[0070] In some embodiments of this utility model, reference is made to Figure 1 The tailpipe input terminal 504 is also connected to the hydrogen tailpipe terminal of the fuel cell stack 1. The cavity structure also includes a gas guiding cavity 503. One end of the gas guiding cavity 503 is connected to the end of the expanded diameter silencing cavity 502, and the other end of the gas guiding cavity 503 is connected to the gas discharge terminal 505. The end portion of the inclined guiding wall 506 is spaced apart from the wall of the gas guiding cavity 503 to form a liquid channel.

[0071] In this embodiment, the air exhaust (humid air) from the cathode of fuel cell stack 1 and the hydrogen exhaust (humid hydrogen and impurities) from the anode are jointly introduced into the same cavity structure for processing through the exhaust input terminal 504. This allows the exhaust gases from the air and hydrogen sides, as well as the liquid water, to mix within the cavity structure, achieving a high degree of integrated processing of the anode and cathode exhaust gases. This significantly improves the system's compactness and economy. Furthermore, the water generated at the cathode and anode of fuel cell stack 1 (carried in through the hydrogen exhaust) is collected uniformly in this device, capturing almost all the liquid water produced by the chemical reaction of fuel cell stack 1. This provides the most abundant internal water source for the humidification module 52, the spray cooling module 53, and the water replenishment module 54, reducing the dependence on external water replenishment.

[0072] In this embodiment, the cavity structure includes both an expanded-diameter silencing cavity 502 and a gas guiding cavity 503. This allows the gas, after being slowed and condensed by the expanded-diameter silencing cavity 502, to flow stably into the gas guiding cavity 503 towards the gas discharge end 505. Furthermore, the liquid channel formed by the cavity structure and the inclined guiding wall 506 ensures that the condensate can flow smoothly and unobstructed to the bottom of the water reservoir 5 by gravity, preventing accumulation or secondary evaporation within the gas flow channel, thus maximizing the water recovery rate. Simultaneously, the cavity structure is filled with a large amount of nitrogen, water vapor, and saturated humid air remaining after rapid condensation from the air and hydrogen exhaust ends. This effectively dilutes the hydrogen concentration, keeping it away from the explosive limit. The water mist and low-temperature walls further suppress the possibility of ignition, effectively improving system safety. This cavity structure eliminates the need for a separate silencer and complex gas-liquid separation device, simplifying the system architecture, reducing material, manufacturing, and assembly costs, and facilitating the miniaturization and integration of the overall system.

[0073] In some embodiments of this utility model, reference is made to Figure 1 The water storage device 5 is provided with a plurality of baffles 508. At least two of the baffles 508 are arranged sequentially on the top of the expanded diameter silencing cavity 502 in a direction away from the tail discharge input end 504. At least one of the baffles 508 is provided on the bottom of the gas guide cavity 503 and is located close to the expanded diameter silencing cavity 502.

[0074] In this embodiment, several baffles 508 arranged sequentially on the top of the expanded diameter silencing cavity 502 along the airflow direction are beneficial for sound waves to strike the baffles 508 to cause reflection and interference, thereby effectively attenuating low-frequency and even some high-frequency noise. Its silencing effect is far superior to that of a simple expanded diameter cavity, which is beneficial to improving the silencing effect of the system. Moreover, while enhancing the silencing function, this structure still does not require any moving parts or additional energy consumption, and is achieved only through structural design, thus maintaining the energy efficiency advantage and reliability of the system. Meanwhile, the baffle 508 disrupts the straight flow of gas, creating complex turbulence and extending the flow path. The airflow entering the cavity structure is forced to bypass the baffle 508, which significantly increases the actual flow path and residence time in the condensation area. This effectively helps hydrogen mix with air and allows water vapor to have a greater chance to contact and condense with the low-temperature cavity wall and the baffle 508 itself. Moreover, the baffle 508 itself provides an additional low-temperature surface, increasing the heat exchange area available for condensation and further enhancing the condensation process. At the same time, when the airflow carrying droplets impacts the baffle 508, the droplets with greater inertia will be captured on the surface of the baffle 508 and coalesce and flow downwards, significantly improving the water recovery rate per unit volume. This baffle 508 can guide the airflow from the expanded diameter silencing cavity 502 into the gas guiding cavity 503 smoothly, avoiding the generation of vortex dead zones or the airflow directly rushing towards the drainage area, ensuring the stable discharge of airflow after gas-liquid separation. The baffle 508, which is set at the bottom of the gas guiding cavity 503 and close to the expanded diameter silencing cavity 502, plays a key role in guiding, stabilizing and blocking water.

[0075] In some embodiments of this utility model, the bottom of the gas guiding cavity 503 is inclined towards the bottom of the device body 501 at the end away from the gas discharge end 505, which is conducive to drainage and avoids water accumulation in the gas guiding cavity 503.

[0076] In some embodiments of this utility model, reference is made to Figure 1 The tail exhaust input terminal 504 is provided with one terminal, which is simultaneously connected to the air tail exhaust pipe 6, the liquid discharge pipe 75 and the gas discharge pipe 77.

[0077] In some other embodiments of this invention, the tailpipe input terminal 504 has three terminals: a first tailpipe input terminal, a second tailpipe input terminal, and a third tailpipe input terminal. One end of the first tailpipe input terminal is connected to the air tailpipe pipeline 6, and the other end of the first tailpipe input terminal is connected to the inlet end of the expanded diameter silencing cavity 502, so as to silence the high-temperature and high-pressure humid air output from the air tailpipe of the fuel cell stack 1. One end of the second tailpipe input terminal is connected to the liquid discharge pipeline 75, and one end of the third tailpipe input terminal is connected to the gas discharge pipeline 77. The other ends of both the second and third tailpipe input terminals are connected to the cavity structure, specifically, either to the expanded diameter silencing cavity 502 or to the gas guiding cavity 503.

[0078] In some embodiments of this utility model, reference is made to Figure 1 The exhaust gas discharged from the gas discharge end 505 can be directly discharged into the atmosphere or discharged into the exhaust gas treatment device 512.

[0079] In some embodiments of this utility model, reference is made to Figure 1 The recycled water discharged from the drainage pipe can be directly discharged into the sewer or the exhaust gas treatment device 512.

[0080] Although the embodiments of this utility model have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of this utility model as described in the claims. Moreover, the utility model described herein may have other embodiments and can be implemented or realized in various ways.

Claims

1. A fuel cell system, characterized in that, include: fuel cell stack; An air subsystem is connected to the air input terminal of the fuel cell stack; A hydrogen subsystem is connected to the hydrogen input terminal of the fuel cell stack; The cooling subsystem includes a cooling circulation loop, a heat dissipation module, and a cooling water tank. The cooling circulation loop is connected to the cooling channels in the fuel cell stack, and the heat dissipation module and the cooling water tank are located on the cooling circulation loop. The tailwater recycling subsystem includes a water storage tank, a tailwater delivery pipeline, a humidification module, a spray cooling module, and a water replenishment module. The water storage tank is connected to the air tailpipe and hydrogen tailpipe of the fuel cell stack. The tailwater delivery pipeline is connected to the water storage tank. The humidification module, the spray cooling module, and the water replenishment module are respectively located on the tailwater delivery pipeline. The humidification module is connected to the air inlet of the air subsystem for humidifying the air supplied to the fuel cell stack. The spray cooling module is connected to the air inlet of the heat dissipation module for spray cooling of the heat dissipation module. The water replenishment module is connected to the cooling water tank for replenishing the cooling water tank with tailwater recycled water.

2. The fuel cell system according to claim 1, characterized in that, The water storage device includes a device body and a cavity structure. The upper part of the device body is provided with a tail discharge input end and a gas discharge end. The cavity structure is located inside the device body and its two ends are respectively connected to the tail discharge input end and the gas discharge end. The tail discharge input end is connected to the air tail discharge end of the fuel cell stack. The cavity structure includes an expanded diameter silencing cavity. The expanded diameter silencing cavity extends from the tail discharge input end in a direction away from the tail discharge input end, and the cross-sectional area of ​​the expanded diameter silencing cavity gradually increases in the direction away from the tail discharge input end. The bottom of the expanded diameter silencing cavity is an inclined guide wall. The end of the inclined guide wall extends in a direction close to the bottom of the device body, and the cavity wall of the expanded diameter silencing cavity is distributed with multiple drainage micro-holes.

3. The fuel cell system according to claim 2, characterized in that, The tailpipe input end is also connected to the hydrogen tailpipe end of the fuel cell stack. The cavity structure also includes a gas guiding cavity. One end of the gas guiding cavity is connected to the end of the expanded diameter silencing cavity, and the other end of the gas guiding cavity is connected to the gas discharge end. The end of the inclined guiding wall and the wall of the gas guiding cavity are spaced apart to form a liquid channel. The water storage device is provided with several baffles. At least two of the baffles are arranged sequentially on the top of the expanded diameter silencing cavity in a direction away from the tail discharge input end, and at least one of the baffles is provided on the bottom of the gas guiding cavity and close to the expanded diameter silencing cavity.

4. The fuel cell system according to claim 1, characterized in that, The fuel cell system further includes a controller, a first liquid level sensor, and a water pump. The first liquid level sensor is located in the water storage tank, and the water pump is located in the tail drain pipeline. The controller is connected to the first liquid level sensor, the water pump, the humidification module, the spray cooling module, and the water replenishment module.

5. The fuel cell system according to claim 4, characterized in that, The humidification module includes a first tailwater delivery branch pipe, a first solenoid valve, a first spray device, and a humidity sensor, all connected to the controller. The humidity sensor is located on the air delivery pipe connecting the air subsystem and the fuel cell stack. The two ends of the first tailwater delivery branch pipe are connected to the tailwater delivery pipe and the first spray device, respectively. The first solenoid valve is located on the first tailwater delivery branch pipe, and the nozzle of the first spray device is positioned facing the air inlet end.

6. The fuel cell system according to claim 4, characterized in that, The spray cooling module includes a second tailwater conveying branch pipe, a second solenoid valve and a second spray device respectively connected to the controller. The two ends of the second tailwater conveying branch pipe are respectively connected to the tailwater conveying branch pipe and the second spray device. The second solenoid valve is located in the second tailwater conveying branch pipe, and the nozzle of the second spray device is set towards the air inlet of the heat dissipation module.

7. The fuel cell system according to claim 4, characterized in that, The water replenishment module includes a third tailwater delivery branch pipe, a third solenoid valve and a second liquid level sensor respectively connected to the controller. The second liquid level sensor is located in the cooling water tank, and the third solenoid valve is located in the third tailwater delivery branch pipe. The two ends of the third tailwater delivery branch pipe are respectively connected to the tailwater delivery pipe and the cooling water tank.

8. The fuel cell system according to claim 4, characterized in that, The tailwater recycling subsystem also includes a drainage module, which includes a drainage pipe, a first drainage valve and a third liquid level sensor respectively connected to the controller. The drainage pipe is connected to the drain outlet at the bottom of the water storage tank. The first drainage valve is located in the drainage pipe. The third liquid level sensor is located in the water storage tank. The third liquid level sensor and the first liquid level sensor are located at different liquid level heights in the water storage tank. The third liquid level sensor is located near the top of the water storage tank, and the first liquid level sensor is located near the bottom of the water storage tank.

9. The fuel cell system according to claim 8, characterized in that, The drainage module also includes a temperature sensor connected to the controller, the temperature sensor being located inside the water reservoir to detect the temperature of the liquid in the water reservoir; And / or, the drainage module further includes a conductivity sensor connected to the controller, the conductivity sensor being disposed within the water reservoir for detecting the conductivity of the liquid in the water reservoir.

10. The fuel cell system according to claim 4, characterized in that, Also includes: An air exhaust control pipeline includes an air exhaust pipeline and a back pressure valve. The two ends of the air exhaust pipeline are respectively connected to the air exhaust end and the exhaust input end of the water storage device. The back pressure valve is installed in the air exhaust pipeline and connected to the controller. The hydrogen tailpipe control pipeline includes a hydrogen tailpipe pipeline, a water distributor, a circulation pump, a second drain valve, and an exhaust valve. The two ends of the hydrogen tailpipe pipeline are connected to the hydrogen tailpipe end and the water distributor, respectively. The drain end of the water distributor is connected to the tailpipe input end of the water storage tank via a liquid discharge pipeline. The second drain valve is located on the liquid discharge pipeline. The exhaust end of the water distributor is connected to the hydrogen subsystem via a hydrogen circulation pipeline. The circulation pump is located on the hydrogen circulation pipeline, and the hydrogen circulation pipeline between the water distributor and the circulation pump is also connected to the tailpipe input end via a gas exhaust pipeline. The exhaust valve is located on the gas exhaust pipeline. The water distributor is equipped with a fourth liquid level sensor. The fourth liquid level sensor, the circulation pump, the second drain valve, and the exhaust valve are all connected to the controller.

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