Fuel cell and low-temperature purging system thereof

Abstract

The utility model provides a fuel cell and a low-temperature purging system thereof, which comprise an air pipeline, a hydrogen pipeline, a drainage pipeline, a hydrogen pressure sensor, a hydrogen circulating pump, an air compressor, an air pressure sensor, a heat dissipation module, an electric pile, an electric pile voltage sensor, an electric pile current sensor and a controller. The fuel cell works and purges in a proper temperature range, the reaction rate in the cell is improved, the damage to the cell caused by overhigh temperature is avoided, the stack entering pressure and flow of air and hydrogen are changed, liquid water in an electric pile and auxiliary parts is quickly blown out of the system, the internal humidity of the system is reduced, and the safety of the system is improved. The icing phenomenon in the galvanic pile and auxiliary parts during low-temperature storage is prevented, and the normal starting of the galvanic pile and the system is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of fuel cells, in particular to a fuel cell and a low-temperature purge system thereof. Background Art

[0002] The application scenarios of automotive fuel cell systems often involve temperatures below zero. After shutdown, how to quickly purge the fuel cell system at sub-zero temperatures to discharge the water generated by the reaction during the previous stage of operation from the stack, prevent the ice chips generated in the membrane electrode and bipolar plate flow channels inside the stack from filling the voids in the porous medium and destroying the diffusion layer structure, hindering oxygen transmission when restarting, and ensuring the normal restart of the stack and system are the key points of fuel cell research in various universities and companies.

[0003] When performing low-temperature purging of automotive fuel cell systems, four aspects need to be paid attention to. First, during the purging process, the stack needs to be maintained at a relatively high temperature to ensure that the liquid water on the internal membrane electrode surface, carbon paper surface, and bipolar plate evaporates quickly. Secondly, the purge time should be short. As an automotive fuel cell system, after the vehicle is shut down, the subjective intention of the personnel is to shut down the vehicle as soon as possible. Thirdly, during the low-temperature purge process, it is necessary to maintain the life of the stack and avoid high potential as much as possible. Finally, auxiliary components with water vapor in the fuel cell system, such as hydrogen circulation pumps, hydrogen exhaust valves, air back pressure valves, etc., need to remove the accumulation of liquid water during the re-purging process to avoid freezing when restarting, and the situation where it cannot be opened or takes a long time to open. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the defect in the prior art that the temperature of water generated by the reaction of the fuel cell after operation is too high in the pipeline, resulting in the failure of the fuel cell stack and the system to operate within the normal temperature range, and to provide a fuel cell and a low-temperature purge system thereof.

[0005] The utility model solves the above technical problems through the following technical solutions: The utility model provides a fuel cell low-temperature purge system, including: an air pipeline, a hydrogen pipeline, a drainage pipeline, a hydrogen pressure sensor, a hydrogen circulation pump, an air compressor, an air pressure sensor, a heat dissipation module, a stack voltage sensor and a stack current sensor, and a controller;

[0006] The air pipeline, the hydrogen pipeline and the drainage pipeline are respectively connected to the fuel cell stack; the hydrogen pipeline is provided with the hydrogen pressure sensor and the hydrogen circulation pump; the air pipeline is provided with the air compressor and the air pressure sensor; the drainage pipeline is provided with the heat dissipation module; the fuel cell stack is provided with the fuel cell stack voltage sensor and the fuel cell stack current sensor; the controller is respectively electrically connected to the hydrogen pressure sensor, the hydrogen circulation pump, the air compressor, the air pressure sensor, the heat dissipation module, the fuel cell stack voltage sensor and the fuel cell stack current sensor.

[0007] Optionally, the heat dissipation module includes: an electronic fan, a heat exchanger, and a fan power distribution control module, and the fan power distribution control module is electrically connected to the electronic fan and the heat exchanger.

[0008] Optionally, the fuel cell low-temperature purge system further comprises: a gas-water separator, the gas-water separator being arranged on the hydrogen pipeline;

[0009] And / or, a hydrogen supply module, wherein the hydrogen supply module is arranged at the inlet of the hydrogen pipeline.

[0010] Optionally, the fuel cell low-temperature purge system further comprises: a hydrogen exhaust valve, wherein the hydrogen exhaust valve is located at the hydrogen exhaust port of the gas-water separator.

[0011] Optionally, the fuel cell low-temperature purge system further comprises: an air filter, the air filter being arranged at the inlet of the air pipeline;

[0012] And / or, an air flow meter, wherein the air flow meter is located between the air filter and the air compressor.

[0013] Optionally, the fuel cell low-temperature purge system further includes: an intercooler, wherein the intercooler is located between the air compressor and the air pressure sensor and is connected to the drainage pipeline.

[0014] Optionally, the fuel cell low-temperature purge system further includes: a back-pressure throttle valve, and the back-pressure throttle valve is located at the outlet of the air pipeline.

[0015] Optionally, the fuel cell low-temperature purge system further comprises: a drainage temperature and pressure sensor, the drainage temperature and pressure sensor being located at the water inlet of the drainage pipeline;

[0016] And / or, a water pump, wherein the water pump is located between the drainage temperature and pressure sensor and the heat dissipation module.

[0017] Optionally, the fuel cell low-temperature purge system further comprises: an electronic thermostat, wherein the electronic thermostat is located between the water pump and the heat dissipation module;

[0018] And / or, a PTC heater, wherein the PTC heater is connected to the electronic thermostat and an outlet of the drainage pipeline.

[0019] A fuel cell comprises the fuel cell low-temperature purge system described in any one of the above items.

[0020] On the basis of conforming to the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present utility model.

[0021] The positive progressive effect of the present invention is that by adding a heat dissipation module, the fuel cell can be operated and purged within a suitable temperature range, the reaction rate inside the battery can be increased, damage to the battery caused by excessively high temperatures can be avoided, and the pressure and flow rate of air and hydrogen entering the stack can be changed, liquid water in the stack and auxiliary components can be quickly blown out of the system, and the humidity inside the system can be reduced, preventing freezing inside the stack and auxiliary components during low-temperature storage, thereby ensuring the normal startup of the stack and the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a schematic structural diagram of a low-temperature purge system for a fuel cell provided in accordance with an exemplary embodiment of the present invention.

[0023] Figure 2 A flow chart of low-temperature purge of a fuel cell provided for an exemplary embodiment of the utility model. DETAILED DESCRIPTION

[0024] A preferred embodiment is given below and combined with the accompanying drawings to more clearly and completely illustrate the present invention, but the present invention is not limited to the scope of the embodiment.

[0025] The prefixes such as "first" and "second" used in the embodiments of the present invention are only used to distinguish different description objects, and have no limiting effect on the position, order, priority, quantity or content of the described objects. The use of prefixes such as ordinal numbers used to distinguish description objects in the embodiments of the present invention does not constitute a limitation on the described objects. The description of the described objects refers to the description in the context of the claims or embodiments, and the use of such prefixes should not constitute an unnecessary limitation. In addition, in the description of the present embodiment, unless otherwise specified, the meaning of "multiple" is two or more.

[0026] Figure 1 A schematic structural diagram of a fuel cell low-temperature purge system provided for an exemplary embodiment of the utility model, comprising: an air pipeline, a hydrogen pipeline, a drainage pipeline, a hydrogen pressure sensor 2, a hydrogen circulation pump 4, an air compressor 8, an air pressure sensor 10, a heat dissipation module 15, a stack voltage sensor 18 and a stack current sensor 19, and a controller;

[0027] The air pipeline, the hydrogen pipeline and the drainage pipeline are respectively connected to the fuel cell stack 17, the hydrogen pipeline is provided with the hydrogen pressure sensor 2 and the hydrogen circulation pump 4, the air pipeline is provided with the air compressor 8 and the air pressure sensor 10, the drainage pipeline is provided with the heat dissipation module 15, the fuel cell stack 17 is provided with the controller, the fuel cell stack voltage sensor 18 and the fuel cell stack current sensor 19, and the controller is respectively electrically connected to the hydrogen pressure sensor 2, the hydrogen circulation pump 4, the air compressor 8, the air pressure sensor 10, the heat dissipation module 15, the fuel cell stack voltage sensor 18 and the fuel cell stack current sensor 19.

[0028] The working mechanism of the low-temperature purge system for a fuel cell provided by an embodiment of the utility model is introduced below.

[0029] After receiving a low-temperature shutdown command during operation, the automotive fuel cell system reduces the load current of the stack 17 to I1. The value of I1 can be set according to user needs. When the conditions are met, the first stage of the purge process begins: the speed of the air compressor 8 is increased from the normal speed to R1 to increase the pressure and flow of air entering the stack 17. The incoming air pressure is measured by the air pressure sensor 10. The pressure of hydrogen entering the stack 17 is set to P1. The speed of the hydrogen circulation pump 4 is increased from the normal speed to R2 to increase the hydrogen inlet pressure of the hydrogen path. The increase in the speed of the hydrogen circulation pump 4 promotes the uniform dispersion of moisture in the anode and hydrogen pipeline of the stack 17, which is beneficial to the drainage of the anode of the stack 17 and reduces the internal gas humidity. The fuel cell stack 17 is composed of multiple fuel cell cells. When the total voltage of the fuel cell stack 17 is less than or equal to U1, or the duration meets T5, or the cell voltage is less than or equal to U3, it enters the second stage of purging. There are two situations for entering the second stage. The first situation is that the total voltage of the fuel cell stack 17 is less than or equal to U1, or the duration meets T5, which is a normal situation. At this time, the speed of the hydrogen circulation pump 4 is set to 0, and other conditions remain unchanged. The purging continues. The purging ends based on the duration T6 or the total voltage of the fuel cell stack 17 is less than or equal to U2; the second situation is that the cell voltage is less than or equal to U3, which is a situation where the cell voltage is low. At this time, the speed of the hydrogen circulation pump 4 is set to 0, and the load current of the fuel cell stack 17 is reduced to 0. Other conditions remain unchanged, and the fuel cell stack 17 is open-circuit purged. The purging ends based on the duration T8. After the second stage of purging, the load current of the stack 17 is set to 0, the speed of the air compressor 8 is set to 0, and the hydrogen inlet pressure is set to P2. In general, the difference between the hydrogen pressure and the air pressure is less than or equal to the difference threshold. The difference threshold can be set by the user according to the actual situation to prevent the pressure difference between hydrogen and air from being too large. When the speed of the air compressor 8 is 0, the discharge current of the stack 17 is set to I2, and the air compressor 8 is turned off at the same time to consume the oxygen concentration on the cathode side of the stack 17. When the total voltage of the stack 17 is less than U4 or the lowest single cell voltage is less than U5, the discharge current is set to 0, and the active discharge of the stack 17 ends. The stack 17 will discharge naturally inside. At this time, the stack 17 will continue to consume the hydrogen at the anode and the remaining oxygen at the cathode. At the same time, the cathode gradually forms a nitrogen-rich environment, and hydrogen continues to be replenished to avoid severe negative pressure at the anode.

[0030] The normal rotation speed of the air compressor 8 is the rotation speed of the air compressor 8 when it operates normally; the normal rotation speed of the hydrogen circulation pump 4 is the rotation speed of the hydrogen circulation pump 4 when it operates normally.

[0031] During the reaction process of the stack 17, the anode reaction (oxidation reaction) is at the anode, and hydrogen molecules are oxidized under the action of the catalyst to generate protons (H+) and electrons (e-). The protons (H+) migrate from the anode of the stack 17 to the cathode through the proton exchange membrane. The function of the proton exchange membrane is to allow protons to pass through while preventing electrons and gases (hydrogen and oxygen) from passing through. Electrons (e-) cannot pass through the proton exchange membrane, so they flow from the anode to the cathode through an external circuit to form an electric current. This current can be used to do work, such as driving a motor or charging a battery.

[0032] At the cathode, oxygen molecules react with protons (H+) that migrate through the proton exchange membrane and electrons (e-) that arrive through the external circuit under the action of the catalyst to produce water.

[0033] The high temperature in the fuel cell will cause part of the generated water to evaporate and form water vapor. The heat dissipation module 15 in the drainage pipeline can recondense these water vapors into liquid water. The drainage pipeline designed for the fuel cell ensures that the generated liquid water can be discharged in time to prevent accumulation inside the battery. This can be achieved by means of a water pump 13 or a capillary effect. The membrane of the fuel cell needs to maintain a certain humidity to maintain its conductivity, so part of the generated water can be used to moisten the proton exchange membrane. A humidity management system (such as a humidifier and a dehumidifier) ​​can adjust the humidity of the gas entering the battery. The heat dissipation module 15 of the fuel cell is used to manage the heat generated during the reaction. Common cooling methods include liquid cooling and air cooling. The liquid cooling system circulates a coolant (such as water or a coolant) to take away the heat, while the air cooling system takes away the heat through air flow. The heat dissipation module 15 of the present application adopts an air cooling system, in which the heat exchanger can be used to transfer the heat generated by the fuel cell to the external environment or other systems that require thermal energy. Heat can be recycled and used for the vehicle's heating system or other auxiliary equipment to improve the energy efficiency of the overall system. The fuel cell system is equipped with temperature sensors and controllers to monitor and adjust the temperature of the battery in real time to ensure that the battery operates within the optimal operating temperature range. Too high a temperature will damage the life and performance of the battery, while too low a temperature will reduce the reaction rate and efficiency.

[0034] This embodiment adds a heat dissipation module to make the fuel cell work and purge within a suitable temperature range, improve the reaction rate inside the battery, and avoid damage to the battery caused by excessive temperature. It also changes the pressure and flow rate of air and hydrogen entering the stack, quickly blows the liquid water in the stack 17 and auxiliary components out of the system, and reduces the humidity inside the system to prevent freezing inside the stack 17 and auxiliary components during low-temperature storage, ensuring the normal startup of the stack 17 and the system.

[0035] In one embodiment, the heat dissipation module includes: an electronic fan, a heat exchanger, and a fan power distribution control module, and the fan power distribution control module is electrically connected to the electronic fan and the heat exchanger.

[0036] In this embodiment, the electronic fan, heat exchanger and fan power distribution control module work together to ensure that the temperature and humidity of the fuel cell are within the optimal range. The electronic fan is driven by an electric motor, which is usually a brushless DC motor with the advantages of high efficiency, durability and low noise. The fan blades rotate, generating air flow to take away heat or provide cooling air. The speed of the electronic fan can be adjusted by voltage or pulse width modulation (PWM) signal to adapt to different cooling needs. The heat exchanger transfers the heat generated by the fuel cell to a cooling medium (such as water or air) by conduction. Common types include air-to-air heat exchangers and liquid-to-air heat exchangers. Heat is absorbed and taken away by the heat exchanger. Heat exchangers are usually made of materials with good thermal conductivity (such as aluminum or copper) to improve heat transfer efficiency.

[0037] The fan power distribution control module provides a stable power supply for the electronic fan and other auxiliary devices (such as the water pump 13 and sensors). The fan power distribution control module receives data from the temperature sensor and adjusts the speed and operating status of the fan according to the preset control logic. The fan speed is adjusted through the pulse width modulation (PWM) signal to meet the cooling requirements of the fuel cell.

[0038] The temperature sensor monitors the temperature of the fuel cell and cooling system and transmits the data to the fan power distribution control module. Based on the temperature feedback, the power distribution control module adjusts the speed of the electronic fan. If the temperature rises, the fan speed increases to enhance heat dissipation; if the temperature drops, the fan speed decreases to save energy. The heat exchanger transfers the heat generated by the fuel cell through the air, and the cooled medium returns to the system to continue absorbing heat.

[0039] In this embodiment, the fan power distribution control module uses parameters such as temperature and humidity to coordinate the operation of the electronic fan and the heat exchanger to achieve optimal heat dissipation management, so that the fuel cell can operate efficiently and stably while ensuring long life and high performance.

[0040] In one embodiment, the fuel cell low-temperature purge system further includes: a gas-water separator 3, which is arranged on the hydrogen pipeline, and / or a hydrogen supply module 1, which is arranged at the inlet of the hydrogen pipeline.

[0041] In this embodiment, the water vapor generated by the reaction in the fuel cell stack is separated, and the liquid water and solid particles in the hydrogen are removed through the five-stage separation principle of speed reduction, centrifugation, collision, change of direction, and condensation. The hydrogen is then sent to the hydrogen circulation pump 4 to participate in the reaction again, and the hydrogen supply module 1 removes impurities and pollutants in the hydrogen to ensure that the hydrogen entering the fuel cell is of high purity and avoid damage to the catalyst of the fuel cell.

[0042] In one embodiment, the fuel cell low-temperature purge system further includes: a hydrogen exhaust valve 5 , and the hydrogen exhaust valve 5 is located at the hydrogen exhaust port of the gas-water separator 3 .

[0043] During the operation of the fuel cell, a portion of the hydrogen may not be able to fully participate in the reaction. The function of the hydrogen discharge valve 5 is to regularly discharge the unreacted hydrogen. On the anode side of the fuel cell, in addition to hydrogen, some impurities (such as nitrogen, oxygen in the air, and water vapor) may accumulate. The hydrogen discharge valve 5 can remove these impurities by regularly exhausting the gas to prevent them from affecting the performance of the fuel cell. The hydrogen discharge valve 5 also helps to maintain the gas flow and pressure balance on the anode side, prevent gas stagnation and excessive local pressure, thereby ensuring the uniformity and stability of the battery reaction. Fuel cell catalysts are very sensitive to the presence of impurities (such as carbon monoxide). Regular hydrogen discharge also helps to reduce the accumulation of these impurities, avoid catalyst poisoning, and extend the service life of the fuel cell.

[0044] In one embodiment, the fuel cell low temperature purge system further includes: an air filter 6, which is arranged at the inlet of the air pipeline. In this embodiment, impurity particles in the air will enter the air pipeline and block the flow channel when entering the fuel cell stack. The air filter needs to filter out these particles and adsorb impurity gases in the air such as SO2, NOx, H2S and other gases that have a great impact on the performance of the fuel cell to ensure the normal reaction of the fuel cell. The air flow meter can detect the flow rate of the air flowing into the pipeline in real time. The model of the air flow meter 7 can be selected according to actual needs. The air flow meter can accurately adjust the air flow rate by detecting the flow rate of the pipeline air, thereby ensuring the normal reaction of the fuel cell stack 17.

[0045] In one embodiment, the fuel cell low temperature purge system further includes: an air flow meter 7, the air flow meter 7 is located between the air filter 6 and the air compressor 8

[0046] In one embodiment, the fuel cell low-temperature purge system further includes: an intercooler 9, wherein the intercooler 9 is located between the air compressor 8 and the air pressure sensor 10, and is connected to the drainage pipeline.

[0047] This embodiment reduces the temperature of the high-temperature air after supercharging by dividing the compressed air, thereby ensuring that the fuel cell stack 17 can operate at a normal operating temperature.

[0048] In one embodiment, the fuel cell low-temperature purge system further includes: a back-pressure throttle valve 11 , and the back-pressure throttle valve 11 is located at the outlet of the air pipeline.

[0049] When the discharge current I2 of the battery stack 17 is set and the air compressor 8 is shut down, the back pressure throttle valve 11 is also closed.

[0050] This embodiment installs a back-pressure throttle valve 11 to adjust the exhaust according to the electrical signal, which can help the fuel cell stack to react better and discharge the exhaust gas.

[0051] In one embodiment, the fuel cell low-temperature purge system further includes: a drainage temperature and pressure sensor 12, and the drainage temperature and pressure sensor 12 is located at the water inlet of the drainage pipeline.

[0052] In this embodiment, the drainage temperature and pressure sensor monitors and adjusts the temperature of the battery stack in real time, and transmits the temperature and pressure signals to the heat dissipation module. The fan power distribution control module in the heat dissipation module adjusts the speed of the electronic fan according to the received temperature and pressure signals. If the temperature rises, the fan speed increases to enhance heat dissipation; if the temperature drops, the fan speed decreases to save energy and ensure that the battery stack operates within the optimal operating temperature range.

[0053] In one embodiment, the fuel cell low-temperature purge system further includes: a water pump 13 , wherein the water pump 13 is located between the drainage temperature and pressure sensor 12 and the heat dissipation module 15 .

[0054] In this embodiment, water pumps are arranged at the battery stack and the electronic thermostat to enhance the ability of the pipeline to transport water.

[0055] In one embodiment, the fuel cell low-temperature purge system further includes: an electronic thermostat 14 , and the electronic thermostat 14 is located between the water pump 13 and the heat dissipation module 15 .

[0056] In this embodiment, the electronic thermostat automatically adjusts the amount of water entering the heat dissipation module according to the water temperature, ensuring that the heat dissipation module operates within a suitable temperature range, thereby saving energy consumption.

[0057] In one embodiment, the fuel cell low-temperature purge system further includes: a PTC heater 16 , wherein the PTC heater 16 is connected to the electronic thermostat 14 and an outlet of the drainage pipeline.

[0058] During the first stage of purging, the rotation and stop time of the water pump 13 is set to T3 and T4, the speed of the water pump 13 is set to the minimum value, and the power of the PTC heater 16 is set to the maximum value. At this time, the internal heat of the battery stack 17 is taken out of the battery stack 17 by the coolant and the cathode air. In order to keep the battery stack 17 at a higher temperature, it is necessary to control the flow of the coolant at a slower speed. However, it cannot stop flowing at the same time to prevent heat accumulation inside the battery stack 17 and the heat of the PTC heater 16 from being transferred to the battery stack 17. The control of the cooling path is very critical, and a large number of experiments are required to control the variables so that the internal temperature of the battery stack 17 is maintained at a higher value.

[0059] In this embodiment, the PTC heater is precisely controlled to ensure that the internal temperature of the battery stack is maintained at a high value, accelerate the evaporation of water, and avoid freezing caused by cold start.

[0060] Figure 2 A flow chart of low-temperature purge of a fuel cell provided for an exemplary embodiment of the utility model.

[0061] After receiving a low-temperature shutdown command during operation, the vehicle fuel cell system reduces the load current of the stack 17 to I1. The value of I1 can be set according to user needs. When the conditions are met, the first stage of the purge process begins: the speed of the air compressor 8 is increased from a preset value to R1 to increase the pressure and flow of air entering the stack 17. The incoming air pressure is measured by the air pressure sensor 10. The pressure of hydrogen entering the stack 17 is set to P1. The speed of the hydrogen circulation pump 4 is increased from a preset value to R2 to increase the hydrogen inlet pressure of the hydrogen path. The increase in the speed of the hydrogen circulation pump 4 promotes uniform dispersion of moisture in the anode and hydrogen pipeline of the stack 17, which is beneficial to the drainage of the anode of the stack 17 and reduces the internal gas humidity. The fuel cell stack 17 is composed of multiple fuel cell cells. When the total voltage of the fuel cell stack 17 is less than or equal to U1, or the duration meets T5, or the cell voltage is less than or equal to U3, the second stage of purging is entered. There are two situations for entering the second stage. The first situation is that the total voltage of the fuel cell stack 17 is less than or equal to U1, or the duration meets T5, which is a normal situation. At this time, the speed of the hydrogen circulation pump 4 is set to 0, and other conditions remain unchanged. The purging continues. The purging ends based on the duration T6 or the total voltage of the fuel cell stack 17 is less than or equal to U2; the second situation is that the cell voltage is less than or equal to U3, which is a situation where the cell voltage is low. At this time, the speed of the hydrogen circulation pump 4 is set to 0, and the load current of the fuel cell stack 17 is reduced to 0. Other conditions remain unchanged, and the fuel cell stack 17 is open-circuit purged. The purging ends based on the duration T8. After the second stage of purging, the load current of the stack 17 is set to 0, the speed of the air compressor 8 is set to 0, and the hydrogen entry pressure is set to P2. In general, the difference between the hydrogen pressure and the air pressure is less than or equal to the difference threshold. The difference threshold can be set by the user according to the actual situation to prevent the pressure difference between hydrogen and air from being too large. When the speed of the air compressor 8 is 0, the discharge current of the stack 17 is set to I2, and the air compressor 8 is turned off at the same time to consume the oxygen concentration on the cathode side of the stack 17. When the total voltage of the stack 17 is less than U4 or the lowest single cell voltage is less than U5, the discharge current is set to 0, and the active discharge of the stack 17 ends. The stack 17 will discharge naturally inside. At this time, the stack 17 will continue to consume the hydrogen at the anode and the remaining oxygen at the cathode. At the same time, the cathode gradually forms a nitrogen-rich environment, and the hydrogen is continuously replenished for a period of time that meets T9. The hydrogen supply is turned off to avoid severe negative pressure at the anode.

[0062] This embodiment controls the pressure and flow rate of air and hydrogen entering the stack to quickly blow liquid water in the battery stack and auxiliary components out of the system, and reduces the humidity inside the system to prevent freezing inside the battery stack and auxiliary components during low-temperature storage, thereby ensuring normal startup of the battery stack and the system.

[0063] A fuel cell comprises the fuel cell low-temperature purge system described in any one of the above items.

[0064] The fuel cell in this embodiment may have one or more fuel cell low-temperature purge systems, which is not particularly limited in this embodiment of the utility model.

[0065] Although the specific implementations of the utility model are described above, those skilled in the art should understand that this is only an example, and the protection scope of the utility model is defined by the attached claims. Those skilled in the art can make various changes or modifications to these implementations without departing from the principle and essence of the utility model, but these changes and modifications fall within the protection scope of the utility model.

Claims

1. A fuel cell low temperature purge system, characterized in that: include: Air pipelines, hydrogen pipelines, drainage pipelines, hydrogen pressure sensors, hydrogen circulation pumps, air compressors, air pressure sensors, heat dissipation modules, stack voltage sensors and stack current sensors, and controllers; The air pipeline, the hydrogen pipeline and the drainage pipeline are respectively connected to the fuel cell stack; the hydrogen pipeline is provided with the hydrogen pressure sensor and the hydrogen circulation pump; the air pipeline is provided with the air compressor and the air pressure sensor; the drainage pipeline is provided with the heat dissipation module; the fuel cell stack is provided with the fuel cell stack voltage sensor and the fuel cell stack current sensor; the controller is respectively electrically connected to the hydrogen pressure sensor, the hydrogen circulation pump, the air compressor, the air pressure sensor, the heat dissipation module, the fuel cell stack voltage sensor and the fuel cell stack current sensor.

2. The fuel cell low temperature purge system according to claim 1, characterized in that: The heat dissipation module comprises: an electronic fan, a heat exchanger, and a fan power distribution control module. The fan power distribution control module is electrically connected to the electronic fan and the heat exchanger.

3. The fuel cell low temperature purge system according to claim 1, characterized in that: The fuel cell low-temperature purge system further includes: a gas-water separator, which is arranged on the hydrogen pipeline; And / or, a hydrogen supply module, wherein the hydrogen supply module is arranged at the inlet of the hydrogen pipeline.

4. The fuel cell low temperature purge system according to claim 3, characterized in that: The fuel cell low-temperature purge system further includes: a hydrogen exhaust valve, which is located at the hydrogen exhaust port of the gas-water separator.

5. The fuel cell low temperature purge system according to any one of claims 1 to 4, characterized in that: The fuel cell low-temperature purge system further includes: an air filter, the air filter being arranged at the inlet of the air pipeline; And / or, an air flow meter, wherein the air flow meter is located between the air filter and the air compressor.

6. The fuel cell low temperature purge system according to any one of claims 1 to 4, characterized in that: The fuel cell low-temperature purge system further includes an intercooler, which is located between the air compressor and the air pressure sensor and connected to the drainage pipeline.

7. The fuel cell low temperature purge system according to any one of claims 1 to 4, characterized in that: The fuel cell low-temperature purge system further includes: a back-pressure throttle valve, and the back-pressure throttle valve is located at the outlet of the air pipeline.

8. The fuel cell low temperature purge system according to any one of claims 1 to 4, characterized in that: The fuel cell low-temperature purge system further includes: a drainage temperature and pressure sensor, the drainage temperature and pressure sensor being located at the water inlet of the drainage pipeline; And / or, a water pump, wherein the water pump is located between the drainage temperature and pressure sensor and the heat dissipation module.

9. The fuel cell low temperature purge system according to claim 8, characterized in that: The fuel cell low-temperature purge system further includes: an electronic thermostat, wherein the electronic thermostat is located between the water pump and the heat dissipation module; And / or, a PTC heater, wherein the PTC heater is connected to the electronic thermostat and an outlet of the drainage pipeline.

10. A fuel cell, characterized in that: It comprises a fuel cell low-temperature purge system as claimed in any one of claims 1 to 9.

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