Fuel cell tail exhaust hydrogen concentration detection and mixing dilution device and new energy vehicles

Abstract

The invention discloses a fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device and a new energy vehicle. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device comprises a hydrogen concentration detection unit and a mixing and dilution unit. The hydrogen concentration detection unit comprises a tail exhaust main line, a sampling branch line, a gas-liquid separator and a hydrogen concentration sensor. The gas-liquid separator is used to first significantly cool down and dehumidify the incoming tail exhaust gas, so that the use environment of the hydrogen concentration sensor is optimized and the detection accuracy is improved. The mixing and dilution unit comprises a fan and a ventilation gas branch line. The outlet end of the ventilation gas branch line is connected to the tail exhaust main line. The fan blows external air into the inlet end of the ventilation gas branch line, and the hydrogen concentration of the tail exhaust in the tail exhaust main line is diluted by the external air. The hydrogen concentration of the tail exhaust in the tail exhaust main line is diluted by the external air, so as to further improve the safety.

Description

Technical field:

[0001] The invention relates to a fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device and a new energy vehicle. Background technology:

[0002] The fuel cell system uses the electrochemical reaction between hydrogen stored in the gas cylinder and oxygen from the air to generate electricity and provide a power source for electrical equipment. Hydrogen and oxygen are separated by the fuel cell exchange membrane, but there is inevitably a phenomenon of mutual penetration; during the reaction, liquid water will gather in the hydrogen path, which needs to be discharged in time. Usually, a purge solenoid valve is used to discharge water and impurities in the hydrogen path to the air path outlet for mixing to reduce the hydrogen concentration and avoid deflagration. Therefore, the fuel cell system needs to install a hydrogen concentration sensor at the air path outlet to monitor and control the hydrogen concentration at the outlet in real time. As a flammable gas, hydrogen has an explosion limit of 4% to 75.6%. Therefore, the concentration of discharged hydrogen needs to be reduced to below 4% to avoid danger.

[0003] Normally, the operating temperature of a fuel cell is relatively high, and the gas at the air outlet is of high temperature and high humidity. In this operating environment, a special hydrogen concentration sensor is required, which is generally a heated hydrogen concentration sensor. The cost of use is very high, and the performance is unstable, resulting in high maintenance costs for the fuel cell system, and even affecting the safety and performance of the fuel cell system.

[0004] In patent CN 208076472U, a venturi tube and a waterproof breathable membrane are used to prevent the hydrogen concentration sensor from being used in a high temperature and high humidity environment. However, this device increases the flow resistance of the tail pipe and there is a risk of clogging of the waterproof breathable membrane, which can easily cause inaccurate detection.

[0005] In patent CN 108493467A, a large number of valves are used to control the hydrogen content of the exhaust gas of the fuel cell. The number of components is large, the control is relatively complex, and the use of ordinary hydrogen concentration sensors in high temperature and high humidity environments is not solved. Summary of the invention:

[0006] The first purpose of the present invention is to provide a fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device and a new energy vehicle, while solving two technical problems existing in the prior art: 1) the accuracy and reliability of hydrogen concentration detection are low in a high temperature and high humidity environment; 2) the hydrogen concentration of the tail exhaust is too high, posing a dangerous hazard.

[0007] A further object of the present invention is to provide a fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device and a new energy vehicle, so as to solve the technical problem that in the prior art, hydrogen concentration detection in a high temperature and high humidity environment requires the use of a special hydrogen concentration sensor, resulting in very high use cost and high maintenance cost.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device, characterized in that it includes a hydrogen concentration detection unit and a mixing and dilution unit, wherein: the hydrogen concentration detection unit includes a tail exhaust main line, a sampling branch line, a gas-liquid separator and a hydrogen concentration sensor, wherein the inlet of the sampling branch line is connected to the upstream section of the tail exhaust main line, the gas-liquid separator includes an inner shell, a cavity is arranged in the inner shell, a tail exhaust outlet pipe, a tail exhaust inlet pipe and a condensed water outlet pipe are arranged on the inner shell, the tail exhaust outlet pipe, the tail exhaust inlet pipe and the condensed water outlet pipe are all connected to the cavity, and the outlet of the sampling branch line is connected to the upstream section of the tail exhaust main line. The tail exhaust inlet pipe is connected to the gas-liquid separator, and a hydrogen concentration sensor is installed on the gas-liquid separator. The tail exhaust entering the sampling branch pipeline can be directly discharged through the tail exhaust outlet pipe, or the tail exhaust outlet pipe is connected to the downstream section of the tail exhaust main pipeline through an auxiliary pipeline to return the tail exhaust entering the sampling branch pipeline to the tail exhaust main pipeline; the mixing and dilution unit includes a fan and a ventilation gas branch pipeline, the outlet end of the ventilation gas branch pipeline is connected to the tail exhaust main pipeline, the fan blows external air into the inlet end of the ventilation gas branch pipeline, and uses the external air to dilute the hydrogen concentration of the tail exhaust in the tail exhaust main pipeline.

[0010] The gas-liquid separator described above also includes an outer shell, which is mounted on the outside of the inner shell, and the gap between the inner shell and the outer shell forms an air duct. The outer shell has an air inlet and an air outlet. The inlet end of the ventilation gas branch pipeline is connected to the air outlet of the outer shell. A fan is installed at the air inlet of the outer shell. The fan draws external cold air into the air duct and blows it on the outer surface of the inner shell to form an air cooling effect.

[0011] The top of the inner shell mentioned above protrudes from the outer shell.

[0012] The inner diameter D2 of the sampling branch pipeline mentioned above is smaller than the inner diameter D1 of the tail exhaust main pipeline.

[0013] The top of the inner shell is provided with a tail exhaust outlet pipe, and the bottom of the inner shell is provided with a tail exhaust inlet pipe and a condensed water outlet pipe.

[0014] A detection hole is opened on the top wall of the inner shell, the detection hole is connected to the cavity, the hydrogen concentration sensor is installed on the inner shell, and the probe part of the hydrogen concentration sensor extends into the detection hole to sense the hydrogen concentration.

[0015] The detection hole is located close to the tail exhaust outlet pipe.

[0016] The first mounting platform is arranged on the wall surface of the inner shell around the detection hole, and the hydrogen concentration sensor is mounted on the mounting platform.

[0017] The hydrogen concentration sensor described above is a non-heating type hydrogen concentration sensor.

[0018] A second mounting platform is arranged at the position of the air inlet of the outer shell, and the fan is mounted on the second mounting platform.

[0019] The second installation platform is staggered with the first installation platform at an angle.

[0020] A new energy vehicle comprises a vehicle body, a drive motor and a fuel cell, wherein the drive motor and the fuel cell are mounted on the vehicle body, the drive motor provides power for the vehicle body, the fuel cell provides electrical energy for the drive motor, the fuel cell comprises a stack module, an electrical control component, a hydrogen path system, a cooling circuit system and an air path system, the stack module is formed by stacking a number of fuel cell monomers from bottom to top, the hydrogen path system comprises a hydrogen inlet valve component, a hydrogen circulation pump and a purge valve; the air path system comprises an air compressor, an air cooler and a humidifier; a fuel cell tail exhaust hydrogen concentration detection and mixing dilution device is installed at the outlet of the air path system, characterized in that: the fuel cell tail exhaust hydrogen concentration detection and mixing dilution device is the above-mentioned fuel cell tail exhaust hydrogen concentration detection and mixing dilution device

[0021] Compared with the prior art, the present invention has the following effects:

[0022] 1) The hydrogen concentration detection unit of the present invention comprises a tail exhaust main line, a sampling branch line, a gas-liquid separator and a hydrogen concentration sensor, wherein the inlet of the sampling branch line is connected to the upstream section of the tail exhaust main line, the gas-liquid separator comprises an inner shell, a cavity is arranged in the inner shell, a tail exhaust outlet pipe, a tail exhaust inlet pipe and a condensed water outlet pipe are arranged on the inner shell, the tail exhaust outlet pipe, the tail exhaust inlet pipe and the condensed water outlet pipe are all connected to the cavity, the outlet of the sampling branch line is connected to the tail exhaust inlet pipe of the gas-liquid separator, the hydrogen concentration sensor is installed on the gas-liquid separator, the tail exhaust outlet pipe can be used to directly discharge the tail exhaust entering the sampling branch line, or the tail exhaust outlet pipe is connected to the downstream section of the tail exhaust main line through an auxiliary line, and the tail exhaust entering the sampling branch line is returned to the tail exhaust main line. The tail exhaust entering the tail exhaust hydrogen concentration detection device is first separated into gas and liquid by a gas-liquid separator to reduce the humidity of the tail exhaust, and the tail exhaust entering the tail exhaust hydrogen concentration detection device is cooled by the gas-liquid separator, thereby improving the accuracy and reliability of hydrogen concentration detection. At the same time, because the fuel cell tail exhaust hydrogen concentration detection device of the present invention first significantly cools the incoming tail exhaust and dehumidifies it, the use environment of the hydrogen concentration sensor is optimized, and the common non-heating hydrogen concentration sensor on the market can be used, without the need for a specially made hydrogen concentration sensor, thereby significantly reducing costs.

[0023] 2) The mixing and dilution unit of the present invention includes a fan and a ventilation gas branch pipeline. The outlet end of the ventilation gas branch pipeline is connected to the tail exhaust main pipeline. The fan blows external air into the inlet end of the ventilation gas branch pipeline, and uses the external air to dilute the hydrogen concentration of the tail exhaust in the tail exhaust main pipeline, thereby reducing the concentration and temperature of the hydrogen in the tail exhaust of the fuel cell and greatly improving safety.

[0024] 3) The new energy vehicle of the present invention improves the safety and reliability of the fuel cell system and reduces the cost because the detection accuracy and reliability of the fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device adopted are high.

[0025] 4) Other advantages of the present invention are described in detail in the embodiments. Description of the drawings:

[0026] Figure 1 A schematic structural diagram of Embodiment 1 of the present invention;

[0027] Figure 2 It is a schematic diagram of the installation of the gas-liquid separator, the hydrogen concentration sensor, and the fan according to the first embodiment of the present invention;

[0028] Figure 3 is a front view of a gas-liquid separator according to a first embodiment of the present invention;

[0029] Figure 4yes Figure 3 AA section view;

[0030] Figure 5 yes Figure 3 BB cross-sectional view;

[0031] Figure 6 is a structural diagram of Embodiment 2 of the present invention;

[0032] Figure 7 is a schematic diagram of the structure of Embodiment 3 of the present invention;

[0033] Figure 8 It is a circuit block diagram of embodiment 3 of the present invention. Specific implementation method:

[0034] The present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0035] Embodiment 1:

[0036] like Figures 1 to 5 As shown, this embodiment provides a fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device, including a hydrogen concentration detection unit and a mixing and dilution unit, wherein:

[0037] The hydrogen concentration detection unit includes a tail exhaust main line 5, a sampling branch line 4, a gas-liquid separator 2 and a hydrogen concentration sensor 1, wherein the inlet 41 of the sampling branch line 4 is connected to the upstream section 51 of the tail exhaust main line 5, the gas-liquid separator 2 includes an inner shell 20, a cavity 2b is arranged in the inner shell 20, a tail exhaust outlet pipe 2c, a tail exhaust inlet pipe 2d and a condensed water outlet pipe 2e are arranged on the inner shell 20, the tail exhaust outlet pipe 2c, the tail exhaust inlet pipe 2d and the condensed water outlet pipe 2e are all connected to the cavity 2b, the outlet 42 of the sampling branch line 4 is connected to the tail exhaust inlet pipe 2d of the gas-liquid separator 2, the hydrogen concentration sensor 1 is installed on the gas-liquid separator 2, the tail exhaust outlet pipe 2c is connected to the downstream section 52 of the tail exhaust main line 5 through an auxiliary line 3, and the tail exhaust entering the sampling branch line 4 is returned to the tail exhaust main line 5. The upstream section 51 of the tail exhaust main line 5 is the tail exhaust inlet section, and the downstream section 52 of the tail exhaust main line 5 is the tail exhaust outlet section. The tail exhaust entering the tail exhaust hydrogen concentration detection device is first separated into gas and liquid by a gas-liquid separator to reduce the humidity of the tail exhaust, and the tail exhaust entering the tail exhaust hydrogen concentration detection device is cooled by a gas-liquid separator, thereby improving the accuracy and reliability of hydrogen concentration detection. At the same time, since the fuel cell tail exhaust hydrogen concentration detection device of the present invention first significantly cools and dehumidifies the incoming tail exhaust, the use environment of the hydrogen concentration sensor is optimized, and a common hydrogen concentration sensor on the market can be used, and no special hydrogen concentration sensor is required, so the cost can be greatly reduced.

[0038] The mixing and dilution unit includes a fan 6 and a ventilation gas branch pipeline 7. The outlet end of the ventilation gas branch pipeline 7 is connected to the tail exhaust main pipeline 5. The fan 6 blows external cold air into the inlet end of the ventilation gas branch pipeline 7, and uses the external air to dilute the hydrogen concentration of the tail exhaust in the tail exhaust main pipeline 5. The structure is simple and reasonable, and the implementation is easy and reliable.

[0039] The gas-liquid separator 2 also includes an outer shell 21, and the outer shell 21 is mounted on the outside of the inner shell 20. The gap between the inner shell 20 and the outer shell 21 forms an air duct 2a. The outer shell 21 has an air inlet 2j and an air outlet 2k. The inlet end of the ventilation gas branch pipeline 7 is connected to the air outlet 2k of the outer shell 21. A fan 6 is installed at the air inlet 2j of the outer shell 21. The fan 6 draws external cold air into the air duct 2a and blows it on the outer surface of the inner shell 20 to form an air-cooling effect, which is more conducive to the heat dissipation of the inner shell 20. The structure is compact, the layout is reasonable, the integration is high, it is conducive to reducing product costs, and it is easy to install.

[0040] The top of the inner shell 20 protrudes from the outer shell 21, which is convenient for arranging the mounting platform 2g to mount the hydrogen concentration sensor 1. The structure is simple and reasonable, and the cost is saved.

[0041] The inner diameter D2 of the sampling branch pipeline 4 is smaller than the inner diameter D1 of the tail exhaust main pipeline 5 . The sampling branch pipeline 4 with a smaller diameter forms a negative pressure, and the tail gas in the tail exhaust main pipeline 5 with a larger diameter is sucked into the sampling branch pipeline 4 .

[0042] The inner diameter D2 of the sampling branch pipeline 4 and the inner diameter D3 of the auxiliary pipeline 3 may be the same as or different from each other, without any specific requirements.

[0043] The gas-liquid separator 2 described above is a natural cooling condenser, an air-cooled condenser, or a liquid-cooled condenser. Various condensers are easily available, have simple structures, and are low in cost.

[0044] A tail exhaust outlet pipe 2c is arranged at the top of the inner shell 20 described above, and a tail exhaust inlet pipe 2d and a condensed water outlet pipe 2e are arranged at the bottom of the inner shell 20. The condensed water outlet pipe 2e is used to discharge the water collected in the cavity 2b in the inner shell 20. The structure is simple, the layout is reasonable, and it is easy to detect.

[0045] A detection hole 2f is opened on the wall of the inner shell 20, and the detection hole 2f is connected to the cavity 2b. The hydrogen concentration sensor 1 is installed on the inner shell 20, and the probe part of the hydrogen concentration sensor 1 extends into the detection hole 2f to sense the hydrogen concentration. The structure is simple and the installation is convenient.

[0046] The detection hole 2f is located close to the tail exhaust outlet pipe 2c, which improves the accuracy and reliability of detection because the tail exhaust near the exhaust outlet pipe 2c has been significantly cooled, cooled and dehumidified.

[0047] The mounting platform 2g is arranged on the wall surface of the inner shell around the detection hole 2f, and the hydrogen concentration sensor is mounted on the mounting platform 2g, which is simple and convenient to install.

[0048] The hydrogen concentration sensor 1 described above is a non-heating type hydrogen concentration sensor, which is beneficial to reducing costs, is easy to obtain materials, and has low maintenance costs.

[0049] The second mounting platform 2i is arranged at the position of the air inlet 2j of the outer shell 21, and the fan 6 is mounted on the second mounting platform 2i, which has a simple structure and is easy to install.

[0050] The second installation platform 2i and the first installation platform 2g are staggered at an angle to facilitate installation and avoid interference.

[0051] Embodiment 2:

[0052] like Figure 6 As shown, this embodiment is a modification of the first embodiment, and the modification is: the tail exhaust outlet pipe 2c is used to directly discharge the tail exhaust entering the branch pipeline 4, the auxiliary pipeline 3 is deleted, and the structure is simpler.

[0053] Embodiment three:

[0054] A new energy vehicle comprises a vehicle body, a drive motor and a fuel cell, wherein the drive motor and the fuel cell are mounted on the vehicle body, the drive motor provides power for the vehicle body, and the fuel cell provides electrical energy for the drive motor, such as Figure 7 , Figure 8 As shown, the fuel cell includes a stack module, an electrical control component, a hydrogen circuit system, a cooling circuit system and an air circuit system. The stack module is formed by stacking a number of fuel cell monomers from bottom to top. The hydrogen circuit system includes a hydrogen inlet valve component, a hydrogen circulation pump and a purge valve; the air circuit system includes an air compressor, an air cooler and a humidifier; a fuel cell tail exhaust hydrogen concentration detection and mixing dilution device is installed at the outlet of the air circuit system, and the fuel cell tail exhaust hydrogen concentration detection and mixing dilution device is the fuel cell tail exhaust hydrogen concentration detection and mixing dilution device described in Example 1 or Example 2

[0055] The gas at the outlet of the air path of the fuel cell is high temperature and high humidity. The gas-liquid separator of the first and second embodiments is used to separate the tail gas entering the tail exhaust hydrogen concentration detection device into gas and liquid to reduce the humidity of the tail gas. At the same time, the gas-liquid separator is used to cool the tail gas entering the tail exhaust hydrogen concentration detection device, thereby improving the accuracy and reliability of hydrogen concentration detection, making the fuel cell system safer and having better performance. The hydrogen concentration of the tail gas in the tail exhaust main path 5 is diluted by external air, the structure is simple and reasonable, the implementation is easy and reliable, and the safety is further improved, which is conducive to significantly reducing the hydrogen concentration in the exhaust gas and avoiding the risk of explosion.

[0056] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited thereto. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention are equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device, characterized in that: It includes a hydrogen concentration detection unit and a mixing and dilution unit, wherein: The hydrogen concentration detection unit comprises a tail exhaust main line, a sampling branch line, a gas-liquid separator and a hydrogen concentration sensor, wherein the inlet of the sampling branch line is connected to the upstream section of the tail exhaust main line, the gas-liquid separator comprises an inner shell, a cavity is arranged in the inner shell, a tail exhaust outlet pipe, a tail exhaust inlet pipe and a condensed water outlet pipe are arranged on the inner shell, the tail exhaust outlet pipe, the tail exhaust inlet pipe and the condensed water outlet pipe are all connected to the cavity, the outlet of the sampling branch line is connected to the tail exhaust inlet pipe of the gas-liquid separator, the hydrogen concentration sensor is installed on the gas-liquid separator, the tail exhaust entering the sampling branch line can be directly discharged by the tail exhaust outlet pipe, or the tail exhaust outlet pipe is connected to the downstream section of the tail exhaust main line through an auxiliary line, and the tail exhaust entering the sampling branch line is returned to the tail exhaust main line; The mixing and dilution unit includes a fan and a ventilation gas branch pipeline. The outlet end of the ventilation gas branch pipeline is connected to the tail exhaust main pipeline. The fan blows external air into the inlet end of the ventilation gas branch pipeline, and uses the external air to dilute the hydrogen concentration of the tail exhaust in the tail exhaust main pipeline.

2. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 1 is characterized in that: The gas-liquid separator also includes an outer shell, which is mounted on the outside of the inner shell, and the gap between the inner shell and the outer shell forms an air duct. The outer shell has an air inlet and an air outlet. The inlet end of the ventilation gas branch pipeline is connected to the air outlet of the outer shell. A fan is installed at the air inlet of the outer shell. The fan draws external cold air into the air duct and blows it on the outer surface of the inner shell to form an air cooling effect.

3. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 2 is characterized in that: The top of the inner shell protrudes from the outer shell.

4. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 2 or 3, characterized in that: The inner diameter D2 of the sampling branch pipeline is smaller than the inner diameter D1 of the tail exhaust main pipeline.

5. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 4 is characterized in that: A tail exhaust outlet pipe is arranged at the top of the inner shell, and a tail exhaust inlet pipe and a condensed water outlet pipe are arranged at the bottom of the inner shell.

6. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 5, characterized in that: A detection hole is opened on the top wall of the inner shell, the detection hole is communicated with the cavity, the hydrogen concentration sensor is installed on the inner shell, and the probe part of the hydrogen concentration sensor extends into the detection hole to sense the hydrogen concentration.

7. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 6 is characterized in that: The detection hole is located close to the tail exhaust outlet pipe.

8. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 7, characterized in that: A first mounting platform is arranged on the wall surface of the inner shell around the detection hole, and the hydrogen concentration sensor is mounted on the mounting platform.

9. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 8, characterized in that: The hydrogen concentration sensor is a non-heating type hydrogen concentration sensor.

10. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 7, characterized in that: A second mounting platform is arranged at the position of the air inlet of the outer shell, and the fan is mounted on the second mounting platform.

11. The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device according to claim 10, characterized in that: The second installation platform is staggered at an angle with the first installation platform.

12. A new energy vehicle, comprising a vehicle body, a drive motor and a fuel cell, wherein the drive motor and the fuel cell are mounted on the vehicle body, the drive motor provides power for the vehicle body, the fuel cell provides electrical energy for the drive motor, the fuel cell comprises a stack module, an electrical control component, a hydrogen circuit system, a cooling circuit system and an air circuit system, the stack module is formed by stacking a number of fuel cell monomers from bottom to top, the hydrogen circuit system comprises a hydrogen inlet valve assembly, a hydrogen circulation pump and a purge valve; the air circuit system comprises an air compressor, an air cooler and a humidifier; a fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device is installed at the outlet of the air circuit system, characterized in that: The fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device is the fuel cell tail exhaust hydrogen concentration detection and mixing and dilution device as described in any one of claims 1 to 11 above.

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