System for improving in-pile air humidity

Abstract

The utility model relates to the technical field of fuel cells, in particular to a system for improving in-pile air humidity, which comprises an air inlet pipeline and a humidifying pipeline, a humidifying device, an air compressing device and a temperature adjusting device are sequentially arranged on the air inlet pipeline in the air inlet direction. One end of the humidifying pipeline is communicated with an exhaust port of the electric pile, the humidifying device is located on the humidifying pipeline, and the humidifying pipeline provides humid and hot air for the humidifying device; the tail end of the air inlet pipeline is communicated with an air inlet of the electric pile. The utility model has the advantages that the humidifying device is arranged in front of the air compression device, so that the air is humidified under low pressure, the absolute humidity of the air can be improved, the aim of improving the relative humidity of the air is fulfilled through the subsequent pressurization and cooling of the air pressurizing device and the temperature adjusting device, and the service life of the galvanic pile is prolonged. Meanwhile, a temperature pre-adjusting device is further arranged, the air is heated before humidification, the absolute humidity of the humidified air is higher, and the final relative humidity of the air is further improved.

Description

Technical Field

[0001] The utility model relates to the technical field of fuel cells, in particular to a system for increasing the humidity of the air entering the stack. Background Art

[0002] In the field of hydrogen fuel cells, in order to ensure the performance and service life of the stack, the air required for the stack reaction needs to be humidified before entering the stack. At present, the commonly used air humidification method is membrane humidifier humidification. The conventional humidifier is arranged behind the intercooler. After the dry air enters the humidifier, it exchanges heat and humidity with the wet air at the outlet of the stack. The dry air is heated and humidified and then enters the stack. Due to the limitations of the humidifier itself, the relative humidity of the dry air after being humidified (relative to the inlet coolant temperature value) can only reach about 40% - 60%. The relatively low humidity of the air entering the stack will reduce the performance and service life of the fuel cell. Summary of the Utility Model

[0003] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a system for increasing the humidity of the air entering the stack.

[0004] The purpose of the utility model is realized by the following technical solutions: A system for increasing the humidity of the air entering the stack, comprising:

[0005] An intake pipeline, on which a humidifying device, an air compression device and a temperature regulating device are sequentially arranged along the intake direction;

[0006] A humidifying pipeline, one end of which is communicated with the exhaust port of the stack, the humidifying device is located on the humidifying pipeline, and the humidifying pipeline provides hot and humid air for the humidifying device;

[0007] The end of the intake pipeline is communicated with the intake port of the stack.

[0008] By arranging the humidifying device before the air compression device, the air is humidified in a relatively low-pressure state before being pressurized by the air compression device. At this time, the total pressure of the air is relatively low, and the volume percentage of water in the air is the saturated vapor pressure divided by the total pressure of the air. Therefore, the relatively low total pressure of the air can increase the absolute moisture content of the air. Therefore, humidifying the air before the air compression device can increase the absolute humidity of the air. After the air is cooled by the temperature regulating device after passing through the air compression device, the saturated vapor pressure of the air decreases, further increasing the relative humidity of the air, so that the air entering the stack has a relatively high relative humidity and the service life of the stack is prolonged.

[0009] In some embodiments, the temperature regulating device includes a cooling pipeline and an intercooler. The inlet end of the cooling pipeline is connected to a coolant source, the outlet end of the cooling pipeline is connected to the coolant inlet of the fuel cell stack, the intercooler is located on the cooling pipeline, and the cooling pipeline provides a cold source for the intercooler. After the air is compressed by the air compression device, its temperature rises. The relatively cold coolant before entering the fuel cell stack is used to cool the air to increase the relative humidity of the air.

[0010] In some embodiments, a cooling regulating valve is provided on the cooling pipeline. The cooling regulating valve can control the flow rate of the coolant in the cooling pipeline to adjust the degree of cooling of the air.

[0011] In some embodiments, a controller is further included. The cooling regulating valve is electrically connected to the controller; a first temperature sensor is provided at a position on the intake pipeline between the temperature regulating device and the fuel cell stack, and the first temperature sensor is electrically connected to the controller. The first temperature sensor monitors the air temperature coming out of the temperature regulating device and then feeds it back into the controller, and the controller then controls the opening degree of the cooling regulating valve to keep the air entering the fuel cell stack within a certain temperature range.

[0012] In some embodiments, a temperature pre-regulating device is further included. The temperature pre-regulating device includes an air heater, and the air heater is provided on the intake pipeline and is located at the front end of the humidifying device. The temperature pre-regulating device warms the air before the humidifying device to increase the saturation vapor pressure, further improve the working efficiency of the humidifying device, and further increase the absolute humidity content of the air.

[0013] In some embodiments, the temperature pre-regulating device further includes a heating pipeline. The inlet end of the heating pipeline is connected to the coolant outlet of the fuel cell stack, and the outlet end of the heating pipeline is connected to the coolant inlet of the fuel cell stack; the air heater is located on the heating pipeline, and the heating pipeline provides a heat source for the air heater. The temperature of the coolant discharged from the fuel cell stack is relatively high. This part of the relatively high-temperature coolant is used to warm the air and at the same time cool the coolant.

[0014] In some embodiments, a heating regulating valve is provided on the heating pipeline. The heating regulating valve controls the flow rate of the coolant in the heating pipeline to control the degree of heating of the air by the temperature pre-regulating device.

[0015] In some embodiments, the heating regulating valve is electrically connected to the controller. The heating regulating valve is controlled by the controller.

[0016] In some embodiments, a second temperature sensor is disposed at a position on the intake air pipeline between the humidifying device and the air compression device, and the second temperature sensor is electrically connected to the controller. Through the monitoring and feedback data of the second temperature sensor, it is convenient for the controller to control the opening degree of the heating regulating valve, so that the temperature of the humidified air is stabilized within a certain range.

[0017] In some embodiments, the air compression device includes an air compressor, and the air compressor is used to pressurize air.

[0018] The present utility model has the following advantages:

[0019] 1. By arranging the air humidifying device before the air compression device, the air is humidified under a state of relatively low total pressure, which improves the absolute moisture content of the air. Then, under the cooling of the subsequent temperature regulating device, the relative humidity of the air is increased, so that the air entering the fuel cell stack has a high humidity, and the service life of the fuel cell stack is prolonged.

[0020] 2. The present utility model also arranges a temperature pre-regulating device before the humidifying device to heat the air before the humidifying device, which increases the saturation vapor pressure of the air. As a result, the efficiency of the humidifying device is improved, the absolute moisture content of the air is further increased, and thus the relative humidity of the air entering the fuel cell stack is further increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the system for improving the humidity of the air entering the fuel cell stack in Embodiment 1 of the present utility model;

[0022] Figure 2 is a schematic structural diagram of the system for improving the humidity of the air entering the fuel cell stack in Embodiment 2 of the present utility model;

[0023] In the figure: 1. Intake air pipeline; 2. Humidifying device; 3. Air compression device; 41. Intercooler; 42. Cooling pipeline; 421. Cooling regulating valve; 5. Humidifying pipeline; 6. Controller; 7. First temperature sensor; 81. Air heater; 82. Heating pipeline; 821. Heating regulating valve; 9. Second temperature sensor; 10. Fuel cell stack. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model, and are not used to limit the present utility model. That is, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Usually, the components of the embodiments of the present utility model described and shown in the drawings herein can be arranged and designed in various different configurations.

[0025] The following further describes the present utility model in conjunction with the accompanying drawings, but the protection scope of the present utility model is not limited to the following description.

[0026] Embodiment 1:

[0027] As Figure 1 shown, a system for increasing the humidity of the air entering the stack includes an intake pipeline 1 and a humidification pipeline 5; a humidifying device 2, an air compression device 3, and a temperature regulating device are sequentially arranged on the intake pipeline 1 along the intake air direction; one end of the humidification pipeline 5 is communicated with the exhaust port of the fuel cell stack 10, the humidifying device 2 is located on the humidification pipeline 5, and the humidification pipeline 5 provides hot and humid air for the humidifying device 2; the end of the intake pipeline 1 is communicated with the intake port of the fuel cell stack 10.

[0028] In this embodiment, by arranging the humidifying device 2 at the front end of the air compression device 3, the air is humidified in a relatively low-pressure state before being pressurized, thereby improving the humidification efficiency. Subsequently, after being compressed by the air compression device 3 and cooled by the temperature regulating device, the relative humidity of the air is increased, achieving the purpose of extending the service life of the fuel cell stack 10. Through the humidifying device 2, the high-temperature and high-humidity exhaust gas discharged from the fuel cell stack 10 is used to humidify and heat the air, making full use of the exhaust gas generated by the fuel cell stack 10.

[0029] Preferably, the temperature regulating device includes a cooling pipeline 42 and an intercooler 41. The inlet end of the cooling pipeline 42 is communicated with a coolant source, the outlet end of the cooling pipeline 42 is communicated with the coolant inlet of the fuel cell stack 10, the intercooler 41 is located on the cooling pipeline 42, and the cooling pipeline 42 provides a cold source for the intercooler 41.

[0030] In this embodiment, the coolant source connected to the inlet end of the cooling pipeline 42 is the coolant diverted from the coolant inlet of the fuel cell stack 10. The temperature of the coolant here is relatively low, which is beneficial to cooling the air. When the coolant enters the intercooler 41 to cool the air and then re-enters the coolant inlet end of the fuel cell stack 10 through the cooling pipeline 42 to continue to play a cooling role in the fuel cell stack 10, the temperature of the air is reduced after being cooled, the saturation vapor pressure is reduced, and thus the relative humidity of the air is increased. At this time, the air entering the fuel cell stack 10 for reaction is beneficial to extending the service life of the fuel cell stack 10.

[0031] Preferably, a cooling regulating valve 421 is arranged on the cooling pipeline 42. The cooling regulating valve 421 can adjust the flow rate of the coolant to control the temperature of the cooled air, so that the temperature of the air entering the fuel cell stack 10 is controllable.

[0032] Preferably, it further includes a controller 6, and the cooling regulating valve 421 is electrically connected to the controller 6; a first temperature sensor 7 is disposed at a position on the intake pipeline 1 between the temperature regulating device and the fuel cell stack 10, and the first temperature sensor 7 is electrically connected to the controller 6. By arranging the first temperature sensor 7 between the temperature regulating device and the fuel cell stack 10, and using the feedback data of the first temperature sensor 7, the controller 6 controls the opening degree of the cooling regulating valve 421, so that the air entering the fuel cell stack 10 is always maintained within a certain range or reaches a specified temperature.

[0033] Preferably, the air compression device 3 includes an air compressor. The air compressor is used to pressurize the air.

[0034] In this embodiment, the humidification process of the air is as follows: dry air enters the humidifying device 2 through the intake pipeline 1. At the same time, the hot and humid air discharged from the fuel cell stack 10 also enters the humidifying device 2 through the humidifying pipeline 5. After the dry air is humidified and heated by the hot and humid air, the air temperature rises to 56 °C, the pressure drops to 98 kPa(A), and the absolute humidity content of the humidified air is 0.079 kg water / kg dry air. The humidified air enters the air compression device 3 and is pressurized to 135 kPa(A), and the air temperature rises to 103 °C. At this temperature and pressure, the relative humidity drops to 13.4%, and the absolute humidity content remains 0.079 kg water / kg dry air. The pressurized air enters the temperature regulating device and is cooled to 65 °C, and the relative humidity increases to about 60%. Finally, the air enters the fuel cell stack 10.

[0035] Embodiment 2:

[0036] As Figure 2 shown, the difference between this embodiment and Embodiment 1 is that in this embodiment, it further includes a temperature pre-regulating device, and the temperature pre-regulating device includes an air heater 81, and the air heater 81 is disposed on the intake pipeline 1 and at the front end of the humidifying device 2.

[0037] In this embodiment, by using the temperature pre-regulating device, the air before entering the humidifying device 2 is heated to increase the saturation vapor pressure. After the heated air enters the humidifying device 2, due to the increase in the saturation vapor pressure, the humidification efficiency is improved, the absolute humidity content of the air is further increased, and finally the relative humidity of the air is increased.

[0038] Preferably, the temperature pre-adjustment device further includes a heating pipeline 82. The inlet end of the heating pipeline 82 is communicated with the coolant outlet of the fuel cell stack 10, and the outlet end of the heating pipeline 82 is communicated with the coolant inlet of the fuel cell stack 10. The air heater 81 is located on the heating pipeline 82, and the heating pipeline 82 provides heat source for the air heater 81. The heating pipeline 82 utilizes the relatively high-temperature coolant discharged from the fuel cell stack 10 to heat the air, so that the waste heat of the coolant can be utilized.

[0039] Preferably, a heating regulating valve 821 is provided on the heating pipeline 82. The heating regulating valve can adjust the coolant flow rate in the heating pipeline 82 to control the temperature of the heated air.

[0040] Preferably, the heating regulating valve 821 is electrically connected to the controller 6. The electrical connection between the heating regulating valve 821 and the controller 6 enables automatic control of the heating regulating valve 821.

[0041] Preferably, a second temperature sensor 9 is provided at a position on the intake pipeline 1 between the humidifying device 2 and the air compression device 3. The second temperature sensor 9 is electrically connected to the controller 6. By providing the second temperature sensor 9, the second temperature sensor 9 feeds back the temperature of the humidified air to the controller 6, and the controller 6 adjusts the heating regulating valve 821 according to the temperature data, so that the temperature of the humidified air is always maintained within a certain range.

[0042] In this embodiment, the humidifying process of the air is as follows: Dry air enters the air heater 81 through the intake pipeline 1. At the same time, the relatively high-temperature coolant discharged from the fuel cell stack 10 also enters the air heater 81 through the heating pipeline 82 to heat the air. After the ambient normal-temperature and normal-pressure air is heated, it is transported to the humidifying device 2 through the intake pipeline 1. In the humidifying device 2, at the same time, the humid and hot air discharged from the fuel cell stack 10 also enters the humidifying device 2 through the humidifying pipeline 5 to humidify and heat the dry air. The controller 6 controls the opening degree of the heating valve, thereby controlling the temperature of the dry air entering the humidifying device 2, and through the monitoring of the second temperature sensor 9, the temperature of the air flowing out of the humidifying device 2 is controlled at 62 °C. At this time, the air pressure drops to 95 kPa(A). Since the dry air is heated first and then humidified, the absolute humidity content of the air reaches 0.112 kg water / kg dry air at this time. The humidified air enters the air compression device 3 and is pressurized to 135 kPa(A), and the air temperature rises to 110 °C. At this temperature and pressure, the relative humidity drops to 14.5%, and the absolute humidity content remains 0.112 kg water / kg dry air. The pressurized air enters the temperature adjustment device and is cooled to 65 °C, and the relative humidity increases to about 80%. Finally, the air enters the fuel cell stack 10.

[0043] The above are only the preferred embodiments of the present utility model and do not impose any formal restrictions on the present utility model. Any person skilled in the art can, without departing from the scope of the technical solution of the present utility model, make many possible changes and modifications to the technical solution of the present utility model by using the above-mentioned technical content, or modify it into equivalent embodiments with equivalent changes. Therefore, all content that does not depart from the technical solution of the present utility model, any changes, modifications, equivalent changes and modifications made to the above embodiments based on the technology of the present utility model all fall within the protection scope of this technical solution.

Claims

1. A system for increasing the humidity of air entering a pile, characterized in that: include: An air intake pipeline (1), wherein a humidifying device (2), an air compressing device (3) and a temperature regulating device are sequentially arranged on the air intake pipeline (1) along an air intake direction; A humidifying pipeline (5), one end of which is connected to an exhaust port of the fuel cell stack (10), the humidifying device (2) is located on the humidifying pipeline (5), and the humidifying pipeline (5) provides hot and humid air for the humidifying device (2); The end of the air intake pipeline (1) is connected to the air intake port of the fuel cell stack (10).

2. A system for increasing the humidity of air entering the pile according to claim 1, characterized in that: The temperature regulating device comprises a cooling pipeline (42) and an intercooler (41); the inlet end of the cooling pipeline (42) is connected to a coolant source, the outlet end of the cooling pipeline (42) is connected to a coolant inlet of the fuel cell stack (10), the intercooler (41) is located on the cooling pipeline (42), and the cooling pipeline (42) provides a cold source for the intercooler (41).

3. A system for increasing the humidity of air entering the pile according to claim 2, characterized in that: The cooling pipeline (42) is provided with a cooling regulating valve (421).

4. A system for increasing the humidity of air entering the pile according to claim 3, characterized in that: It also includes a controller (6), the cooling regulating valve (421) being electrically connected to the controller (6); a first temperature sensor (7) is provided on the intake pipeline (1) at a position between the temperature regulating device and the fuel cell stack (10), and the first temperature sensor (7) is electrically connected to the controller (6).

5. A system for increasing the humidity of air entering the pile according to claim 4, characterized in that: It also includes a temperature pre-adjustment device, which includes an air heater (81). The air heater (81) is arranged on the air intake pipeline (1) and is located at the front end of the humidification device (2).

6. A system for increasing the humidity of air entering the pile according to claim 5, characterized in that: The temperature pre-adjustment device also includes a heating pipeline (82), the inlet end of the heating pipeline (82) is connected to the coolant outlet of the fuel cell stack (10), and the outlet end of the heating pipeline (82) is connected to the coolant inlet of the fuel cell stack (10); the air heater (81) is located on the heating pipeline (82), and the heating pipeline (82) provides a heat source for the air heater (81).

7. A system for increasing the humidity of air entering the pile according to claim 6, characterized in that: The heating pipeline (82) is provided with a heating regulating valve (821).

8. A system for increasing the humidity of air entering the pile according to claim 7, characterized in that: The heating regulating valve (821) is electrically connected to the controller (6).

9. A system for increasing the humidity of air entering the pile according to claim 8, characterized in that: A second temperature sensor (9) is provided on the air intake pipeline (1) at a position between the humidifying device (2) and the air compressing device (3), and the second temperature sensor (9) is electrically connected to the controller (6).

10. A system for increasing the humidity of air entering the stack according to claim 1, characterized in that: The air compression device (3) comprises an air compressor.

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