CN118522919A - Fuel cell system based on injection humidification - Google Patents

Abstract

The present invention discloses a fuel cell system based on ejection humidification, including a fuel cell stack, a hydrogen feed pipeline, a first ejector, a first humidity detection device, a humidification pipeline, a control valve and a controller, wherein the outlet end of the hydrogen feed pipeline is connected to the fuel cell stack, the first ejector is arranged on the hydrogen feed pipeline, the first humidity detection device is also arranged on the hydrogen feed pipeline and is located between the first ejector and the fuel cell stack, the outlet end of the humidification pipeline is connected to the first ejector, the control valve is arranged on the humidification pipeline, an ideal humidity value is pre-stored in the controller, and the controller is electrically connected to the control valve and the first humidity detection device respectively. The present invention can control the humidity of hydrogen feed in the fuel cell system, and at the same time remove the moisture of the humid air so that it can safely enter the turbine generator, thereby improving the battery performance and the reliability of the system.

Description

A fuel cell system based on induced humidification

Technical Field

The invention relates to the technical field of fuel cells, and in particular to a fuel cell system based on induced humidification.

Background Art

In a fuel cell, hydrogen needs to enter the membrane electrode of the cell through the intake pipe and undergo an electrochemical reaction. The humidity in the hydrogen feed has an important impact on the working state and life of the cell: if the humidity of the hydrogen feed is too high, water droplets will be generated in the cell, causing "flooding" inside the stack and reducing the battery performance; if the humidity of the hydrogen feed is too low, the water content of the proton exchange membrane will be too low, reducing the battery performance. The current mainstream approach to increasing the humidity of the hydrogen feed is to directly inject excess wet hydrogen into the new hydrogen through an injector to increase the humidity. However, this approach cannot control the specific humidity of the hydrogen feed, and is not convenient for controlling the humidity of the hydrogen feed within a more suitable range, and cannot fully exert the performance of the fuel cell stack.

Summary of the invention

The purpose of the present invention is to overcome the above technical deficiencies and propose a fuel cell system based on induced humidification to solve the technical problem in the prior art that the specific humidity of the hydrogen feed cannot be controlled, thus affecting the performance of the fuel cell stack.

In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

The present invention provides a fuel cell system based on induced humidification, comprising:

Battery stack;

A hydrogen feed pipeline, the outlet end of which is connected to the fuel cell stack;

A first ejector, which is arranged on the hydrogen feed pipeline;

A first humidity detection device, which is arranged on the hydrogen feed pipeline and located between the first ejector and the fuel cell stack;

A humidification pipeline, the outlet end of which is connected to the first ejector;

A control valve, which is arranged on the humidification pipeline;

A controller is provided, wherein an ideal humidity value is pre-stored in the controller, and the controller is electrically connected to the control valve and the first humidity detection device respectively.

In some embodiments, the fuel cell system further includes an air feed line, an outlet end of the air feed line is connected to the fuel cell stack.

In some embodiments, the fuel cell system also includes a heat exchanger, which is arranged on the air feed pipeline. The heat exchanger has a water vapor outlet end and an air outlet end. The water vapor outlet end is connected to the humidification pipeline, and the air outlet end is connected to the fuel cell stack.

In some embodiments, the fuel cell system further includes an air compressor, which is disposed on the air feed pipeline before the heat exchanger.

In some embodiments, the fuel cell system further includes a second humidity detection device, which is disposed on the air feed pipeline and located between the heat exchanger and the fuel cell stack.

In some embodiments, the fuel cell system further includes a second ejector, which is disposed on the hydrogen feed pipeline before the first ejector.

In some embodiments, the fuel cell system also includes a gas-water separator and a turbine generator, the gas-water separator is formed with a first inlet, a second inlet, a first outlet and a second outlet, the first inlet and the second inlet are respectively connected to the excess hydrogen outlet and the excess air outlet of the fuel cell stack, and the first outlet and the second outlet are respectively connected to the second ejector and the turbine generator.

In some embodiments, the gas-water separator is further formed with a drain port, and the drain port is connected to the heat exchanger.

In some embodiments, the gas-water separator includes a shell and a partition, the partition is arranged inside the shell to divide the space inside the shell into a first separation chamber and a second separation chamber, the first separation chamber is provided with the first inlet on the side away from the second separation chamber, the first separation chamber is provided with the first outlet at the top, the second separation chamber is provided with a second inlet on the side away from the first separation chamber, the second separation chamber is provided with the second outlet at the top, and the drain outlet is provided at the bottom of the shell and is connected to both the first separation chamber and the second separation chamber.

In some embodiments, the fuel cell system further includes a water vapor exhaust pipeline and an air exhaust pipeline, the water vapor exhaust pipeline is connected to the control valve, and the air exhaust pipeline is connected to the turbine generator.

Compared with the prior art, the present invention provides a fuel cell system based on ejection humidification, which connects a humidification pipeline to the first ejector and sets a control valve on the humidification pipeline. When the hydrogen feed humidity obtained by the first humidity detection device is greater than the ideal humidity value pre-stored in the controller, the control valve is controlled to reduce the opening, so that the water vapor flow ejected through the first ejector is reduced, thereby reducing the hydrogen humidity in the hydrogen feed pipeline; when the hydrogen feed humidity obtained by the first humidity detection device is less than the ideal humidity value pre-stored in the controller, the control valve is controlled to increase the opening, so that the water vapor flow ejected through the first ejector is increased, thereby increasing the hydrogen humidity in the hydrogen feed pipeline. Such repeated adjustments can maintain the hydrogen feed humidity within a suitable numerical range, so as to fully utilize the energy of hydrogen and avoid damage to the battery, thereby improving the performance of the fuel cell.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a structural block diagram of a fuel cell system based on induced humidification provided by an embodiment of the present invention;

FIG2 is a schematic structural diagram of the gas-water separator provided in an embodiment of the present invention;

FIG3 is a working principle diagram of a fuel cell system based on induced humidification according to an embodiment of the present invention.

The following are the descriptions of the reference numerals:

1. Fuel cell, 2. Hydrogen feed pipeline, 3. First ejector, 4. First humidity detection device, 5. Humidification pipeline, 6. Control valve, 7. Air feed pipeline, 8. Heat exchanger, 9. Air compressor, 10. Second humidity detection device, 11. Second ejector, 12. Gas-water separator, 121. First inlet, 122. First outlet, 123. Second inlet, 124. Second outlet, 125. Drain, 126. Shell, 127. Partition, 13. Turbine generator, 14. Water vapor exhaust pipeline, 15. Air exhaust pipeline.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

In order to solve the technical problem of controlling the specific humidity of hydrogen feed in a fuel cell system, the present invention provides a fuel cell system based on induced humidification, which can control the specific humidity of hydrogen feed in the fuel cell system to improve the performance of the battery stack.

Please refer to Figure 1, which is a structural block diagram of a fuel cell system based on ejection humidification according to an embodiment of the present invention. The fuel cell system includes a fuel cell stack 1, a hydrogen feed pipeline 2, a first ejector 3, a first humidity detection device 4, a humidification pipeline 5, a control valve 6 and a controller. The fuel cell stack 1 is a core component of the fuel cell system, which is used for hydrogen and oxygen to react to generate electrical energy. The inlet end of the hydrogen feed pipeline 2 is connected to an external hydrogen source, and the outlet end of the hydrogen feed pipeline 2 is connected to the fuel cell stack 1 to provide hydrogen for the reaction of the fuel cell stack 1; the first ejector 3 is arranged on the hydrogen feed pipeline 2, The first humidity detection device 4 is also arranged on the hydrogen feed pipeline 2, and is used to obtain the hydrogen feed humidity in the hydrogen feed pipeline 2 in real time; the inlet end of the humidification pipeline 5 is connected to the water vapor supply equipment, and the outlet end of the humidification pipeline 5 is connected to the first ejector 3, and the water vapor in the humidification pipeline 5 is transported to the first ejector 3, so as to increase the humidity of the hydrogen in the first ejector 3; the control valve 6 is arranged on the humidification pipeline 5, and is used to control the discharge amount of the water vapor in the humidification pipeline 5; the ideal humidity value is pre-stored in the controller, and the controller is electrically connected to the control valve 6 and the first humidity detection device 4 respectively.

In this embodiment, a first ejector 3 is provided on the hydrogen feed pipeline 2, and the first ejector 3 is connected to the humidification pipeline 5, so that the water vapor in the humidification pipeline 5 can be transferred to the first ejector 3, mixed with hydrogen and then ejected into the fuel cell stack 1 for reaction. In this process, in order to control the humidity of the hydrogen feed, a first humidity detection device 4 is provided on the hydrogen feed pipeline 2 between the first ejector 3 and the fuel cell stack 1, and a control valve 6 is provided on the humidification pipeline 5. When the actual hydrogen feed humidity obtained by the first humidity detection device 4 is greater than the ideal humidity value pre-stored in the controller, the controller will control the control valve 6. The valve 6 reduces its opening degree, thereby reducing the flow rate of water vapor ejected through the first ejector 3, thereby reducing the humidity of hydrogen in the hydrogen feed pipeline 2; and when the actual hydrogen feed humidity obtained by the first humidity detection device 4 is less than the ideal humidity value pre-stored in the controller, the controller will control the control valve 6 to increase its opening degree, thereby increasing the flow rate of water vapor ejected through the first ejector 3, thereby increasing the humidity of hydrogen in the hydrogen feed pipeline 2. Such repeated adjustments can maintain the hydrogen feed humidity within a suitable numerical range, so as to fully utilize the energy of hydrogen and avoid damage to the battery, thereby achieving the purpose of improving the performance of the fuel cell.

In one of the embodiments, the fuel cell system further includes an air feed line 7, the inlet end of the air feed line 7 is connected to an external air source, and the outlet end of the air feed line 7 is connected to the fuel cell stack 1 to provide air for the fuel cell stack 1 reaction.

In this embodiment, another function of the air feed pipeline 7 is to provide water vapor for the humidification pipeline 5, and the generation of water vapor generally requires the use of a heat exchanger 8. Therefore, in one of the embodiments, the fuel cell system also includes a heat exchanger 8, and the heat exchanger 8 is arranged on the air feed pipeline 7. The heat exchanger 8 is formed with a water vapor outlet end and an air outlet end, and the water vapor outlet end is connected to the humidification pipeline 5, and the air outlet end is connected to the fuel cell stack 1.

In one embodiment, the fuel cell system further includes an air compressor 9 , which is disposed on the air feed pipeline 7 before the heat exchanger 8 .

In this embodiment, the air is compressed by the air compressor 9 and becomes a high-temperature and high-pressure gas, which enters the air feed pipeline 7 and then enters the heat exchanger 8. The liquid water in the heat exchanger 8 is heated by the high-temperature air to form water vapor to be entered into the humidification pipeline 5. At the same time, the cooled air enters the fuel cell stack 1 to participate in the reaction.

In one of the embodiments, the fuel cell system further includes a second humidity detection device 10, which is disposed on the air feed pipeline 7 and located between the heat exchanger 8 and the fuel cell stack 1, and is used to detect the humidity of the air feed.

In one embodiment, the fuel cell system further includes a second ejector 11, which is disposed on the hydrogen feed pipeline 2 before the first ejector 3, and is used for mixing and ejecting excess hydrogen after the hydrogen source reacts with the fuel cell stack 1.

In one embodiment, the fuel cell system also includes a gas-water separator 12 and a turbine generator 13, the gas-water separator 12 is formed with a first inlet 121, a first outlet 122, a second inlet 123 and a second outlet 124, the first inlet 121 and the second inlet 123 are respectively connected to the excess hydrogen outlet and the excess air outlet of the fuel cell stack 1, and the first outlet 122 and the second outlet 124 are respectively connected to the second ejector 11 and the turbine generator 13.

That is to say, in this embodiment, the remaining hydrogen after the reaction of the fuel cell stack 1 is returned to the second ejector 11 through the separation effect of the gas-water separator 12 to continue to participate in the reaction, while the remaining air is sent to the turbine generator 13 for power generation through the separation effect of the gas-water separator 12 to recycle energy. The gas-water separator 12 arranged here can fully separate the moisture in the excess air. Compared with the prior art, the air with moisture removed is sent to the turbine generator 13 for power generation, which will not damage the impeller of the turbine generator 13, and is of great significance to the protection of the equipment.

In one embodiment, the gas-water separator 12 is further formed with a drain port 125, and the drain port 125 is connected to the heat exchanger 8 to transfer the liquid water separated from the gas and water to the heat exchanger 8, providing a water source for the heat exchanger 8 to supply water vapor to the humidification pipeline 5, thereby saving energy.

In one embodiment, the fuel cell system further includes a water vapor exhaust pipeline 14 and an air exhaust pipeline 15, wherein the water vapor exhaust pipeline 14 is connected to the control valve 6, and the air exhaust pipeline 15 is connected to the turbine generator 13, the water vapor exhaust pipeline 14 is used to discharge excess water vapor in the humidification pipeline 5 to the outside of the system, and the air exhaust pipeline 15 is used to discharge air generated by power generation by the turbine generator 13 to the atmosphere outside the system.

In one of the embodiments, please refer to FIG. 2 , the gas-water separator 12 is a two-in-two-out type gas-water separator, which includes a shell 126 and a partition 127. The partition 127 is arranged inside the shell 126 to separate the space inside the shell 126 into a first separation chamber and a second separation chamber. The first separation chamber and the second separation chamber are used to separate hydrogen water vapor and air water vapor, respectively, in this embodiment. In embodiments other than this embodiment, they can also be used to separate two other different gas-water mixtures.

In this embodiment, the first inlet 121 is provided on the side of the first separation chamber away from the second separation chamber, and the first outlet 122 is provided on the top of the first separation chamber. The first inlet 121 is used to enter a mixture of excess hydrogen and water, and the first outlet 122 is used to output the separated hydrogen. Therefore, the first inlet 121 is connected to the excess hydrogen outlet of the fuel cell stack 1, and the first outlet 122 is connected to the second ejector 11; the second inlet 123 is provided on the side of the second separation chamber away from the first separation chamber, and the second outlet 124 is provided on the top of the second separation chamber. The second inlet 123 is used to enter a mixture of excess air and water, and the second outlet 124 is used to input dry air to the turbine generator 13. Therefore, the second inlet 123 is connected to the excess air outlet of the fuel cell stack 1, and the second outlet 124 is connected to the turbine generator 13.

In one of the embodiments, please refer to Figure 2, the drain port 125 is opened at the bottom of the shell 126 and is connected to the first separation chamber and the second separation chamber. The liquid water separated from the first separation chamber and the second separation chamber is discharged from the gas-water separator 12 through the drain port 125, and the drain port 125 is connected to the heat exchanger 8. Therefore, the liquid water discharged from the gas-water separator 12 enters the heat exchanger 8 to provide a water source for the formation of water vapor, thereby effectively utilizing resources.

In order to better understand the present invention, the working principle of the technical solution of the present invention is described as follows in conjunction with FIG3:

First, an ideal humidity of hydrogen feed is pre-stored in the controller, marked as RH0;

Afterwards, the first humidity detection device 4 detects the humidity RH of the hydrogen in the hydrogen feed pipeline 2. When RH>RH0, the controller controls the control valve 6 to reduce its opening, so that the water vapor flow through the first ejector 3 is reduced, thereby reducing the humidity of the hydrogen feed;

When RH＜RH0, the controller controls the valve 6 to increase its opening, so that the water vapor flow through the first ejector 3 increases, thereby increasing the humidity of the hydrogen feed;

When RH=RH0, the opening of the control valve 6 is fixed at this time to maintain the water vapor flow through the first ejector 3 at the current state, thereby maintaining the humidity of the current hydrogen feed.

It should be noted that, under normal circumstances, it is more appropriate to control the hydrogen feed humidity of the fuel cell within the range of 30% to 70%, which can fully utilize the energy of hydrogen and avoid damage to the battery. At the same time, under different working conditions, it is necessary to adjust the humidity according to the specific situation, and regularly maintain the hydrogen feed pipeline 2 to prevent the hydrogen feed pipeline 2 from getting wet, so as to ensure the normal operation of the battery.

In addition, the control valve 6 described in the present invention is a three-way valve, and the first humidity detection device 4 and the second humidity detection device 10 are temperature and humidity detectors.

The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims (10)

1. A fuel cell system based on ejector humidification, comprising:

A galvanic pile;

the outlet end of the hydrogen feeding pipeline is connected with the electric pile;

the first ejector is arranged on the hydrogen feeding pipeline;

The first humidity detection device is arranged on the hydrogen feeding pipeline and is positioned between the first ejector and the galvanic pile;

The outlet end of the humidifying pipeline is connected with the first ejector;

A control valve provided on the humidification line;

and the controller is pre-stored with ideal humidity values and is respectively electrically connected with the control valve and the first humidity detection device.

2. The ejector humidification-based fuel cell system of claim 1, further comprising an air feed line having an outlet end connected to the stack.

3. The ejector humidification-based fuel cell system of claim 2, further comprising a heat exchanger disposed on the air feed line, the heat exchanger being formed with a water vapor outlet end and an air outlet end, the water vapor outlet end being connected to the humidification line, the air outlet end being connected to the electric stack.

4. The ejector humidification-based fuel cell system of claim 3, further comprising an air compressor disposed on the air feed line prior to the heat exchanger charge.

5. The ejector humidification-based fuel cell system of claim 4, further comprising a second humidity detection device disposed on the air feed line between the heat exchanger and the stack.

6. The ejector humidification-based fuel cell system of claim 3, further comprising a second ejector disposed on the hydrogen feed line prior to the first ejector feed.

7. The ejector humidification-based fuel cell system of claim 6, further comprising a gas-water separator and a turbine generator, the gas-water separator formed with a first inlet, a second inlet, a first outlet, and a second outlet, the first inlet and the second inlet being respectively connected to the excess hydrogen outlet and the excess air outlet of the stack, the first outlet and the second outlet being respectively connected to the second ejector and the turbine generator.

8. The ejector humidification-based fuel cell system of claim 7, wherein the gas-water separator is further formed with a drain port connected to the heat exchanger.

9. The injection humidification-based fuel cell system according to claim 8, wherein the gas-water separator comprises a housing and a partition plate, the partition plate is arranged in the housing to divide a space inside the housing into a first separation chamber and a second separation chamber, the first inlet is formed in one side, away from the second separation chamber, of the first separation chamber, the first outlet is formed in the top of the first separation chamber, the second inlet is formed in one side, away from the first separation chamber, of the second separation chamber, the second outlet is formed in the top of the second separation chamber, and the water outlet is formed in the bottom of the housing and is communicated with both the first separation chamber and the second separation chamber.

10. The ejector humidification-based fuel cell system of claim 9, further comprising a water vapor vent line connected to the control valve and an air vent line connected to the turbine generator.