A fuel cell intake system

Abstract

This invention provides a fuel cell intake system. The hydrogen intake system is sequentially connected to a liquid hydrogen tank, an air-temperature vaporizer, and a water-heat exchanger. The oxygen intake system is sequentially connected to an air filter, an air compressor, and an intercooler. A branch line of the air filter outlet is equipped with a fan connected to the air-temperature vaporizer. The air-temperature vaporizer is used for heat exchange between the liquid hydrogen and air, vaporizing the liquid hydrogen and simultaneously liquefying the oxygen in the air, separating it from nitrogen. The outlet line of the air-temperature vaporizer is connected to a gas-liquid separator, and the liquid outlet line of the gas-liquid separator is connected to the air compressor. This intake system reduces the air compressor intake temperature while increasing the oxygen concentration in the fuel cell stack, thereby reducing the air compressor power consumption and improving the fuel cell stack output performance. Utilizing the cold energy of liquid hydrogen to liquefy the oxygen in the air achieves complete or partial separation of oxygen and nitrogen, increasing the oxygen concentration in the system intake.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell technology, and specifically relates to a fuel cell air intake system. Background Technology

[0002] In a fuel cell engine, the fuel cell stack is where the electrochemical reactions occur. In the fuel cell stack, hydrogen gas in the anode chamber loses electrons and becomes protons under the action of the anode catalyst. These protons pass through the proton exchange membrane to the cathode, where they gain electrons under the action of the cathode catalyst and combine with oxygen in the cathode chamber to form water. The output performance of the fuel cell is related to the oxygen concentration in the cathode chamber; the higher the oxygen concentration, the higher the performance.

[0003] In existing fuel cell system technologies, high-pressure gaseous hydrogen storage is commonly used. However, high-pressure gaseous hydrogen storage has a low hydrogen storage density; for the same volume and weight, liquid hydrogen storage can store more hydrogen. In existing liquid hydrogen storage technologies, liquid hydrogen output from the liquid hydrogen tank exchanges heat with the outside air in an ambient temperature vaporizer, vaporizing the liquid hydrogen into gaseous hydrogen. Subsequently, a hydrothermal heat exchanger raises the temperature of the gaseous hydrogen to a level acceptable to the fuel cell stack.

[0004] Existing liquid hydrogen storage technologies do not fully utilize the cold energy of liquid hydrogen, resulting in low energy utilization efficiency. Summary of the Invention

[0005] To fully utilize the cold energy of liquid hydrogen and combine liquid hydrogen storage with a fuel cell system to improve the energy utilization rate of liquid hydrogen storage technology, this invention provides a fuel cell air intake system, including a hydrogen air intake system and an oxygen air intake system, characterized in that:

[0006] The hydrogen intake system is equipped with a liquid hydrogen tank, an air-temperature vaporizer, and a water-heat exchanger. Along the direction of hydrogen flow, the liquid hydrogen tank, air-temperature vaporizer, and water-heat exchanger are connected in sequence by pipelines. The outlet pipeline of the water-heat exchanger is connected to the hydrogen inlet of the fuel cell stack. The air-temperature vaporizer is used for heat exchange between liquid hydrogen and air, which vaporizes the liquid hydrogen and liquefies the oxygen in the air, separating it from the nitrogen.

[0007] The oxygen intake system is equipped with an air filter and an air compressor. Along the oxygen flow direction, the air filter and air compressor are connected in sequence through pipelines, and the air compressor outlet pipeline is connected to the oxygen inlet of the fuel cell stack.

[0008] A fan is installed in the branch line of the air filter outlet line to allow some of the gas from the air filter to enter the air temperature vaporizer. The air temperature vaporizer outlet line is connected to the air compressor inlet. The branch line and the line directly connected to the air filter and air compressor form a parallel line.

[0009] Specifically, an intercooler is installed between the air compressor outlet pipeline and the fuel cell stack oxygen inlet.

[0010] Specifically, the air outlet pipe of the air vaporizer is connected to the gas-liquid separator, and the liquid outlet pipe of the gas-liquid separator is connected to the air inlet of the air compressor.

[0011] Specifically, the gas-liquid separator outlet pipe is connected to the heat sink inlet of the fuel cell stack to improve the heat dissipation capacity of the heat sink. That is, the gas rich in nitrogen at the gas-liquid separator outlet can be guided to the air inlet of heat dissipation devices such as heat sinks to improve the heat dissipation capacity.

[0012] Specifically, the gas-liquid separator is equipped with a vortex generator and a liquid collection chamber. The tail end of the vortex generator pipeline has a flared end, which is connected to the gas outlet pipeline of the gas-liquid separator. The liquid collection chamber is located below the flared end, and the bottom of the liquid collection chamber has a drain pipe, which is connected to the air inlet of the air compressor.

[0013] After the cryogenic gas-liquid mixture enters the gas-liquid separator, it generates eddies through a eddy current generator. Under centrifugal force, the liquid is thrown against the wall, flows along the wall, enters the collection chamber through the flared end, and is discharged from the drain pipe. After passing through the gas-liquid separator, the separation effect of liquid oxygen and nitrogen is improved, and the oxygen concentration of the fuel cell stack is increased.

[0014] Specifically, a permanent magnet is installed in the downstream pipeline of the eddy current generator to improve the gas-liquid separation effect.

[0015] Optionally, an electromagnet can be installed in the downstream pipeline of the eddy current generator to improve the gas-liquid separation effect.

[0016] Because liquid oxygen is ferromagnetic, it can improve the gas-liquid separation effect, allowing as much oxygen-rich liquid as possible to be separated and enter the air compressor.

[0017] Preferably, the air-temperature vaporizer is configured as two air-temperature vaporizers connected in series. After the liquid hydrogen passes through the air-temperature vaporizer, it passes through another air-temperature vaporizer, which further increases the temperature of the hydrogen and prevents the coolant in the hydrothermal heat exchanger from freezing due to excessively low hydrogen temperature.

[0018] Preferably, the gas-liquid separator and the air-temperature vaporizer are integrated into a single design.

[0019] Preferably, since the air compressor intake temperature is reduced, the intercooler at the rear end of the air compressor can be eliminated or reduced in size.

[0020] A fan draws air downstream of the air filter into an ambient air vaporizer, where liquid hydrogen from the liquid hydrogen tank exchanges heat with the air. Since the vaporization temperature of liquid hydrogen is much lower than that of liquid oxygen, and the vaporization temperature of liquid oxygen is higher than that of liquid nitrogen, a well-designed heat exchange structure for the ambient air vaporizer, along with controlled fan and liquid hydrogen flow rates, can lower the temperature of the air after heat exchange to between (or near) the vaporization temperatures of liquid nitrogen and liquid oxygen. After passing through a gas-liquid separator, the oxygen-rich liquid is separated, while the nitrogen-rich gas is released into the atmosphere. The oxygen-rich liquid mixes with the air downstream of the air filter and enters the air compressor, lowering the compressor's inlet temperature while increasing the oxygen concentration in the fuel cell stack, thereby reducing compressor power consumption and improving stack output performance.

[0021] This invention reduces the air compressor intake temperature while increasing the oxygen concentration in the fuel cell stack, thereby reducing the air compressor power consumption and improving the fuel cell stack output performance.

[0022] For fuel cell power systems that use liquid hydrogen for energy storage, the cold energy of liquid hydrogen is used to liquefy oxygen in the air, thereby achieving complete or partial separation of oxygen and nitrogen and increasing the oxygen concentration in the system intake air. Attached Figure Description

[0023] The above and other objects, features and advantages of this disclosure will become more apparent from the accompanying drawings, in which like reference numerals generally denote like parts.

[0024] Figure 1 An embodiment of the present invention provides a fuel cell air intake system;

[0025] Figure 2 A gas-liquid separator for a fuel cell intake system according to an embodiment of the present invention is shown;

[0026] Figure 3 , Figure 4 Two preferred gas-liquid separators for the fuel cell intake system in embodiments of the present invention are shown.

[0027] Figure reference numerals: 1-Air filter; 2-Liquid hydrogen tank; 3-Fan; 4-Air temperature vaporizer; 5-Gas-liquid separator; 6-Hydrothermal heat exchanger; 7-Air compressor; 8-Intercooler; 9-Electric stack; 11-Edge current generator; 12-Flanged opening; 13-Liquid collection chamber; 14-Drain pipe; 15-Permanent magnet; 16-Electromagnet. Detailed Implementation

[0028] Embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0029] The term "comprising" and its variations, as used herein, indicate open inclusion, meaning "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based on". The terms "connected" and "connected" mean a connection or link, directly or indirectly, through other components. The terms "first", "second", etc., may refer to different or the same objects, but do not directly indicate a difference in order or importance. Other explicit and implicit definitions may also be included below.

[0030] like Figure 1 As shown, a fuel cell air intake system;

[0031] It includes a hydrogen intake system and an oxygen intake system. The hydrogen intake system is equipped with a liquid hydrogen tank 2, an air-temperature vaporizer 4, and a water-heat exchanger 6. Along the hydrogen flow direction, the liquid hydrogen tank 2, the air-temperature vaporizer 4, and the water-heat exchanger 6 are connected in sequence by pipelines. The outlet pipeline of the water-heat exchanger 6 is connected to the hydrogen inlet of the fuel cell stack 9. The air-temperature vaporizer 4 is used for heat exchange between liquid hydrogen and air, which vaporizes the liquid hydrogen and liquefies the oxygen in the air, separating it from the nitrogen.

[0032] The oxygen intake system is equipped with an air filter 1, an air compressor 7, and an intercooler 8. Along the oxygen flow direction, the air filter 1, air compressor 7, and intercooler 8 are connected in sequence through pipelines, and the outlet pipeline of the intercooler 8 is connected to the oxygen inlet of the fuel cell stack 9.

[0033] A fan 3 is installed in a branch pipe of the air filter 1 outlet pipe to allow part of the gas coming out of the air filter 1 to enter the air temperature vaporizer 4. The air temperature vaporizer 4 outlet pipe is connected to the air compressor 7 inlet. The branch pipe and the pipe directly connected to the air filter 1 and the air compressor 7 form a parallel pipe.

[0034] The air outlet pipe of the air vaporizer 4 is connected to the gas-liquid separator 5, and the liquid outlet pipe of the gas-liquid separator 5 is connected to the air inlet of the air compressor 7. After mixing with the air downstream of the air filter 1, the liquid enters the air compressor 7.

[0035] A blower 3 draws air downstream of air filter 1 into air-temperature vaporizer 4, where liquid hydrogen from liquid hydrogen tank 2 exchanges heat with the air. By rationally designing the heat exchange structure of air-temperature vaporizer 4 and controlling the matching of blower and liquid hydrogen flow rates, the temperature of the air after heat exchange can be reduced to between (or near) the vaporization temperatures of liquid nitrogen and liquid oxygen. After passing through gas-liquid separator 5, the oxygen-rich liquid is separated, and the nitrogen-rich gas is discharged into the atmosphere. The oxygen-rich liquid mixes with the air downstream of air filter 1 and enters air compressor 7, lowering the inlet temperature of air compressor 7 while increasing the oxygen concentration in fuel cell stack 9, thereby reducing the power consumption of air compressor 7 and improving the output performance of fuel cell stack 9.

[0036] like Figure 2 As shown, the gas-liquid separator of the fuel cell intake system;

[0037] The gas-liquid separator is equipped with a vortex generator 11 and a liquid collection chamber 13. The tail end of the vortex generator 11 pipe has a flared end 12, which is connected to the gas outlet pipe of the gas-liquid separator. The liquid collection chamber 13 is located below the flared end 12, and the bottom of the liquid collection chamber 13 has a drain pipe 14, which is connected to the air inlet of the air compressor.

[0038] After the low-temperature gas-liquid mixture enters the gas-liquid separator, it generates eddies through the eddy generator 11. Under the action of centrifugal force, the liquid is thrown against the wall, flows along the wall, enters the liquid collection chamber 13 after passing through the flared end 12, and is discharged from the drain pipe 14.

[0039] like Figure 3 , Figure 4 Two preferred gas-liquid separators for the fuel cell intake system are shown.

[0040] A permanent magnet 15 or an electromagnet 16 can be installed downstream of the eddy current generator 11. Since liquid oxygen is ferromagnetic, it can improve the gas-liquid separation effect, so that as much oxygen-rich liquid as possible can be separated and enter the air compressor.

[0041] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical applications, or improvements to the prior art of the embodiments, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A fuel cell intake system, comprising a hydrogen intake system and an oxygen intake system, characterized in that: The hydrogen intake system is equipped with a liquid hydrogen tank, an air-temperature vaporizer, and a water-heat exchanger. Along the direction of hydrogen flow, the liquid hydrogen tank, air-temperature vaporizer, and water-heat exchanger are connected in sequence by pipelines. The outlet pipeline of the water-heat exchanger is connected to the hydrogen inlet of the fuel cell stack. The air-temperature vaporizer is used for heat exchange between liquid hydrogen and air, which vaporizes the liquid hydrogen and liquefies the oxygen in the air, separating it from the nitrogen. The oxygen intake system is equipped with an air filter and an air compressor. Along the oxygen flow direction, the air filter and air compressor are connected in sequence through pipelines, and the air compressor outlet pipeline is connected to the oxygen inlet of the fuel cell stack. A fan is installed in the branch line of the air filter outlet line to allow some of the gas from the air filter to enter the air temperature vaporizer. The air temperature vaporizer outlet line is connected to the air compressor inlet. The branch line and the line directly connected to the air filter and air compressor form a parallel line. An intercooler is installed between the air compressor outlet pipeline and the fuel cell stack oxygen inlet; the air temperature vaporizer outlet pipeline is connected to a gas-liquid separator, and the gas-liquid separator outlet pipeline is connected to the air compressor inlet; the gas-liquid separator outlet pipeline is connected to the fuel cell stack radiator inlet to improve the radiator's heat dissipation capacity. The air-temperature vaporizer is configured as two air-temperature vaporizers connected in series to prevent the coolant in the hydrothermal heat exchanger from freezing due to excessively low hydrogen temperature. The gas-liquid separator and the ambient temperature vaporizer are integrated into a single design.

2. The fuel cell intake system according to claim 1, characterized in that, The gas-liquid separator is equipped with a vortex generator and a liquid collection chamber. The tail end of the vortex generator pipeline has a flared end, which is connected to the gas outlet pipeline of the gas-liquid separator. The liquid collection chamber is located below the flared end, and the bottom of the liquid collection chamber has a drain pipe, which is connected to the air inlet of the air compressor.

3. The fuel cell intake system according to claim 2, characterized in that, A permanent magnet is installed in the downstream pipeline of the eddy current generator to improve the gas-liquid separation effect.

4. A fuel cell intake system according to claim 2, characterized in that, An electromagnet is installed in the downstream pipeline of the eddy current generator to improve the gas-liquid separation effect.

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