Fuel cell humidifying system and fuel cell

Abstract

The utility model relates to the technical field of fuel cells, and particularly provides a fuel cell humidifying system and a fuel cell. The fuel cell humidifying system comprises a humidifier, an air supply unit and a water supply unit, the water supply unit is connected with a water replenishing port of the humidifier, the air supply unit is communicated with an air input port of the fuel cell stack, and a steam outlet communicated with the air supply unit is formed in the top of the humidifier; a vacuum pump is arranged at the steam outlet, the running vacuum pump can reduce the pressure in the inner cavity of the humidifier, so that water supplemented into the inner cavity from the water supplementing opening is boiled, and the boiled steam is converged into the air of the air supply unit through the steam outlet. According to the fuel cell humidifying system disclosed by the utility model, the vacuum boiling type humidifier is adopted, so that the running state of the vacuum pump can be adjusted in real time according to the running condition of the fuel cell stack, and the evaporation capacity of water in the inner cavity of the humidifier is further changed, so that the humidity of air supplied to the fuel cell stack by the air supply unit is controlled within a proper range.

Description

Technical Field

[0001] The utility model relates to the technical field of fuel cells, and in particular to a fuel cell humidification system. In addition, the utility model also relates to a fuel cell. Background Art

[0002] A fuel cell power generation system (fuel cell stack) utilizes hydrogen provided by a designated storage system and oxygen from the outside air to generate electricity through an electrochemical reaction. Hydrogen combustion primarily emits water, achieving zero emissions and zero pollution. Therefore, hydrogen energy can address the pollution issues associated with traditional fossil fuel energy.

[0003] However, due to various constraints, key parameters such as fuel cell performance, efficiency, and lifespan are closely related to the water content of the proton exchange membrane during fuel cell operation. Too little water content will increase the internal resistance of the fuel cell and increase the heat generated during operation, which will lead to a decrease in the performance and efficiency of the fuel cell stack system. In severe cases, it may even cause the stack to burn through. If the water content is too high, or too much liquid water enters the fuel cell stack system, it will cause the cathode of the fuel cell stack to be flooded, which will also lead to a decrease in fuel cell system performance. Therefore, during the operation of the fuel cell power generation system, the air supplied from the outside needs to be cooled and humidified to meet the working conditions of the fuel cell stack system.

[0004] At present, most fuel cell systems use membrane tube humidifiers. The working principle is that the high-temperature dry air output by the air compressor enters the input port at one end of the humidifier, and the water vapor discharged from the fuel cell stack enters the input port at the other end of the humidifier. The water in the hot and humid gas discharged by the fuel cell stack is transferred to the other end of the membrane through the permeation membrane to humidify the dry air output by the air compressor to meet the air humidity requirements of the fuel cell system.

[0005] Some fuel cell stack systems also use bubbling or spraying methods for humidification. The bubbling method involves injecting high-temperature dry air from an air compressor into the bottom of a water storage tank, where it is humidified as it passes through the water. The spraying method involves inserting a water spray nozzle into the pipeline from the air compressor to the fuel cell's air inlet. The humidified water, through pressure and atomization, is converted into mist and mixed into the dry air, humidifying the air.

[0006] Although the above method can improve the humidity of the input air of the fuel cell power generation system to a certain extent, its application has the following disadvantages:

[0007] Membrane tube humidifiers are large in size and high in cost. Their humidification effect depends entirely on the characteristics of the internal permeable membrane and is a passive humidification method. As the usage time increases, the characteristics of the internal permeable membrane deteriorate, and the humidification performance of the fuel cell system also decreases, making it impossible to perform active human control and humidity adjustment.

[0008] The bubbling fuel cell humidification method has limitations due to its simple working principle. It is also a passive humidification method, and the humidification effect cannot be actively controlled. Under improper conditions of use, water can easily be brought directly into the fuel cell system, causing flooding.

[0009] As for the spray-type active humidification method, since it directly sprays water mist into the pipeline, it has high requirements for the control of spray volume, spray effect, etc., and cannot accurately control the air humidity according to the different power outputs of the fuel cell system. Moreover, since the atomizing nozzle sprays out small water droplets, they cannot be immediately mixed with dry air to form wet air. After entering the fuel cell system, it is easy to cause flooding. Utility Model Content

[0010] In view of this, the present invention aims to provide a fuel cell humidification system to improve the control effect of the fuel cell intake air humidity.

[0011] In order to achieve the above-mentioned purpose, the technical solution of the utility model is achieved as follows:

[0012] A fuel cell humidification system includes a humidifier, an air supply unit, and a water supply unit;

[0013] The water supply unit is connected to the water replenishment port of the humidifier, the air supply unit is connected to the air input port of the fuel cell stack, and the top of the humidifier is provided with a steam outlet connected to the air supply unit; a vacuum pump is provided at the steam outlet, and the running vacuum pump can reduce the pressure in the inner cavity of the humidifier so that the water replenished into the inner cavity through the water replenishment port boils, and the boiling steam is merged into the air of the air supply unit through the steam outlet.

[0014] Furthermore, the vacuum pump is a diaphragm vacuum pump.

[0015] Furthermore, the humidifier includes a humidifier upper shell and a humidifier lower shell that are snapped together to form the inner cavity, the water replenishment port is arranged on the humidifier lower shell, the steam outlet is arranged at the top of the humidifier upper shell, and the inner cavity of the humidifier upper shell and the inner cavity of the humidifier lower shell are separated by a microporous mesh.

[0016] Furthermore, the humidifier is equipped with a liquid level sensor for monitoring the water level in the inner cavity, and / or the housing of the humidifier is provided with a safety discharge valve.

[0017] Furthermore, the humidifier is equipped with at least one of a water temperature sensor, a cavity temperature sensor, and a cavity pressure sensor; the water temperature sensor is used to monitor the water temperature in the inner cavity, the cavity temperature sensor is used to detect the temperature of the steam in the inner cavity, and the cavity pressure sensor is used to detect the vacuum degree at the top of the inner cavity.

[0018] Furthermore, the air supply unit includes an air compressor, and an air compressor output pipeline, a humidifier air pipeline and a water vapor mixing pipeline which are sequentially connected between the air compressor and the air input port; the humidifier air pipeline is arranged at the bottom of the inner cavity, and the steam outlet is connected to the water vapor mixing pipeline.

[0019] Furthermore, a plurality of heat exchange fins are arranged at intervals on the outer wall of the humidifier air pipeline.

[0020] Furthermore, the water supply unit includes a water storage type water vapor separator and a water supply pipeline; the separator input port of the water storage type water vapor separator is connected to the water vapor outlet of the fuel cell stack, and a condensate outlet is provided at the bottom of the water storage type water vapor separator, and the water supply pipeline is connected between the condensate outlet and the water supply port.

[0021] Furthermore, the level of the condensate outlet is higher than the level of the top of the humidifier, and a control valve is provided on the water supply pipeline.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The fuel cell humidification system of the present invention adopts a vacuum boiling humidifier. By controlling the operating power of the vacuum pump, the vacuum degree of the inner cavity of the humidifier can be changed, and then the evaporation amount of water in the inner cavity of the humidifier can be changed; as the evaporation amount changes, the steam mixed in the air in the air supply unit changes accordingly; in this way, the operating state of the vacuum pump can be adjusted in real time according to the operating conditions of the fuel cell stack, so as to control the humidity of the air supplied to the fuel cell stack by the air supply unit within a suitable range, thereby achieving the purpose of improving the control effect of the fuel cell intake humidity.

[0024] Furthermore, the diaphragm vacuum pump offers stable performance and can be controlled to vary the vacuum level, improving the control of the fuel cell humidification system. The humidifier's split structure facilitates the separate machining of the upper and lower housings, facilitating the installation of temperature, humidity, and liquid level sensors within the internal cavity.

[0025] In addition, if the humidifier air pipeline of the air compressor is arranged at the bottom of the humidifier inner cavity, the humidifier air pipeline will be immersed in the water at the bottom of the inner cavity; in this way, the air flowing through the humidifier air pipeline will produce heat exchange with the water in the inner cavity, which helps to reduce the temperature of the air supplied to the fuel cell stack by the air supply unit, providing good conditions for increasing the air humidity; it is also beneficial to increase the temperature of the water in the inner cavity, thereby providing favorable conditions for water evaporation.

[0026] Another object of the present invention is to provide a fuel cell equipped with the fuel cell humidification system of the present invention. The fuel cell of the present invention has the technical advantages of the above-mentioned fuel cell humidification system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention. Terms such as front and back, top and bottom, etc., used therein are only intended to indicate relative positional relationships and do not constitute improper limitations on the present invention. In the accompanying drawings:

[0028] Figure 1 This is a schematic diagram of the overall structure of the fuel cell humidification system described in an embodiment of the present utility model.

[0029] Description of reference numerals:

[0030] 1. Humidifier; 101. Humidifier air line; 102. Humidifier upper housing; 103. Humidifier lower housing; 104. Air inlet; 105. Air outlet; 106. Heat exchange fins; 107. Water supply port; 108. Microporous mesh; 109. Liquid level sensor; 110. Safety discharge valve; 111. Cavity pressure sensor; 112. Steam outlet; 113. Vacuum pump; 114. Cavity temperature sensor; 115. Water temperature sensor;

[0031] 2. Fuel cell stack; 201. Hydrogen source; 202. Air inlet; 203. Water vapor outlet; 204. Hydrogen supply valve; 205. Hydrogen pipeline; 206. Hydrogen inlet; 207. Hydrogen outlet; 208. Hydrogen exhaust valve; 209. Hydrogen exhaust outlet;

[0032] 3. Water storage type water vapor separator; 301. Overflow collection device; 302. Condensate outlet; 303. Control valve; 304. Water supply pipeline; 305. Separator overflow port; 306. Separator exhaust port; 307. Separator inlet;

[0033] 4. Air compressor; 401. Atmosphere; 402. Air compressor inlet; 403. Air compressor outlet; 404. Air compressor output pipeline; 405. Low-temperature dry air output pipeline; 406. Water vapor output pipeline; 407. Water vapor mixing pipeline. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0035] In the description of this utility model, it should be stated that, unless otherwise expressly defined, the terms "mounted," "connected," "connection," and "connector" should be interpreted broadly. For example, a connection can be a fixed connection, a removable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, an indirect connection through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances.

[0036] Example 1

[0037] This embodiment relates to a fuel cell humidification system, which can improve the control effect of the fuel cell intake humidity; an exemplary system structure is as follows Figure 1 shown.

[0038] In general, the fuel cell humidification system includes a humidifier 1, an air supply unit, and a water supply unit. The water supply unit is connected to the humidifier 1's water inlet 107, while the air supply unit is connected to the fuel cell stack 2's air inlet 202. Furthermore, a steam outlet 112 is located at the top of the humidifier 1, connected to the air supply unit. A vacuum pump 113 is located at steam outlet 112. When operated, vacuum pump 113 reduces the pressure within the humidifier 1's internal cavity, causing the water introduced through the water inlet 107 to boil. The resulting steam then flows through steam outlet 112 and into the air within the air supply unit.

[0039] It should be pointed out that, based on the above-mentioned overall design concept, the technical solution of the present invention can adopt a variety of different specific implementation structures, forms or configuration sequences. For example, the above-mentioned water supply unit can adopt a source of compressed air with stable pressure supply, or it can be supplied by configuring an air compressor. The specific setting sequence, device mode, etc. of the above-mentioned water supply unit, gas supply unit, and the connecting pipes between the humidifier 1 and the fuel cell stack (Stack) 2 can also be flexibly adjusted. For the parts required for the implementation of the overall solution but not involved in the above-mentioned overall setting, reasonable and flexible design can be made with reference to the mature setting means in this field, the actual situation during implementation, etc. The specific implementation scheme described below in this embodiment is only one of the better solutions among the many solutions that can be formed by the above-mentioned various combinations and their variations. In actual implementation, those skilled in the art can make flexible adjustments and improvements based on the actual situation. Obviously, the many solutions that can be formed by the above-mentioned various specific forms of combination and their variations, as well as the specific implementation scheme of this embodiment, are all within the scope of protection of the present utility model.

[0040] As for the specific structure of the humidifier 1, there are of course a variety of structural design forms to choose from; for example, an integrated sealed tank structure can be adopted, or a split sealed cavity structure can be adopted. Specifically, in this embodiment, the humidifier 1 includes a humidifier upper shell 102 and a humidifier lower shell 103 that are buckled together to form an inner cavity, a water replenishment port 107 is provided on the humidifier lower shell 103, and a steam outlet 112 is provided on the top of the humidifier upper shell 102. The humidifier 1 adopts a split structure, which facilitates the separate processing and construction of the humidifier upper shell 102 and the humidifier lower shell 103, and is also conducive to the arrangement of temperature, humidity, liquid level and other detection devices in the inner cavity.

[0041] Since the humidifier 1 has a split structure that snaps together from top to bottom, it is preferred that the water level in the inner cavity be maintained within the inner cavity portion of the humidifier lower housing 103, forming an air cavity in the inner cavity of the portion where the humidifier upper housing 102 is located. The water level in the lower portion boils upward under the action of the vacuum pump 113, forming water vapor in the upper inner cavity. At the same time, it is preferred that a horizontally arranged microporous mesh 108 be provided between the humidifier upper housing 102 and the humidifier lower housing 103 to isolate the inner cavity of the humidifier upper housing 102 from the inner cavity of the humidifier lower housing 103, thereby preventing a large amount of water from being discharged along with the water vapor during the upward boiling process, thereby improving the formation of water vapor. The microporous mesh 108 can be a metal mesh with small pores.

[0042] Vacuum pump 113, located at the top of humidifier 1, can be of various types. In this embodiment, vacuum pump 113 is a diaphragm vacuum pump. This type of diaphragm vacuum pump offers stable operating performance and can vary the vacuum level generated by vacuum pump 113 by controlling the pump's speed, thereby improving the control effectiveness of the fuel cell humidification system.

[0043] In order to monitor the water level, gas temperature and other conditions inside the humidifier 1 in real time; preferably, the humidifier 1 is equipped with a liquid level sensor 109 for monitoring the water level in the inner cavity; the setting of the liquid level sensor 109 provides an effective reference for controlling the water replenishment amount of the water supply unit, which is beneficial to controlling the water level in the inner cavity of the humidifier 1 within a reasonable range and creating a reasonable vacuum space at the upper part of the inner cavity, so that the humidifier 1 can provide sufficient steam.

[0044] At the same time, the humidifier 1 is also equipped with a water temperature sensor 115 for monitoring the water temperature in the inner cavity, a cavity temperature sensor 114 for detecting the steam temperature in the inner cavity, and a cavity pressure sensor 111 for detecting the vacuum degree at the top of the inner cavity. By configuring the humidifier 1 with detection components such as the water temperature sensor 115 and the cavity temperature sensor 114, the temperature of the air and water in the humidifier 1 and the vacuum degree formed in the inner cavity can be monitored in real time; and then by adjusting the water replenishment amount of the water supply unit and the operating speed of the vacuum pump 113, the steam generation effect can be improved and the steam temperature can be changed. Of course, the above-mentioned liquid level sensor 109, water temperature sensor 115, cavity temperature sensor 114, etc. can be flexibly selected and configured. The three can be configured one by one, partially configured, all configured, or none of them can be configured.

[0045] In addition, the housing of the humidifier 1 of this embodiment is also provided with a safety discharge valve 110. As a safety protection device, the safety discharge valve 110 is in a closed state when the humidifier 1 is operating normally, so that the internal pressure of the humidifier 1 is within the normal pressure range; when an abnormal system condition causes the pressure in the inner cavity of the humidifier 1 to become abnormal and exceed the safety limit, the safety discharge valve 110 will immediately open, connecting the interior of the humidifier 1 with the outside world, discharging the abnormal pressure, and ensuring the safety of the humidifier 1. The provision of the safety discharge valve 110 provides a good safety guarantee for the operation of the equipment, can prevent major losses such as equipment damage caused by equipment deflation, and protect the safety of the humidifier 1.

[0046] As mentioned above, the water supply unit and the air supply unit can be configured in a variety of ways. In this embodiment, the following configuration is preferably used.

[0047] The air supply unit of this embodiment includes an air compressor 4, an air compressor output pipeline 404, a humidifier air pipeline 101, and a water vapor mixing pipeline 407, which are sequentially connected between the air compressor 4 and the air input port 202. The air compressor input port 402 of the air compressor 4 is connected to the atmosphere 401. The humidifier air pipeline 101 is arranged at the bottom of the inner cavity. The two ends of the humidifier air pipeline 101 form an air inlet 104 and an air outlet 105 on the outer wall of the humidifier lower shell 103. The air inlet 104 is connected to the air compressor output port 403 of the air compressor 4 through the air compressor output pipeline 404, and the air outlet 105 is connected to the water vapor mixing pipeline 407 through the low-temperature dry air output pipeline 405. The steam outlet 112 is connected to the water vapor mixing pipeline 407 through the water vapor output pipeline 406. The water vapor mixing pipeline 407 simultaneously receives air from the low-temperature dry air output pipeline 405 and water vapor from the water vapor output pipeline 406. The air and water vapor are mixed in the water vapor mixing pipeline 407 and then reach the air input port 202 and enter the fuel cell stack 2.

[0048] The humidifier air pipeline 101 of the air compressor 4 is arranged at the bottom of the inner cavity of the humidifier 1, and the humidifier air pipeline 101 will be immersed in the water at the bottom of the inner cavity; in this way, the air flowing through the humidifier air pipeline 101 will produce heat exchange with the water in the inner cavity, which helps to reduce the temperature of the air supplied to the fuel cell stack 2 by the air supply unit, providing good conditions for increasing the air humidity; at the same time, it is also beneficial to increase the temperature of the water in the inner cavity, thereby providing favorable conditions for the evaporation of water.

[0049] Based on the above configuration, the outer wall of the humidifier air duct 101 of this embodiment is further provided with a plurality of heat exchange fins 106 arranged at intervals. By densely arranging a large number of heat exchange fins 106 on the outer wall of the humidifier air duct 101, the heat exchange performance of the humidifier air duct 101 can be further improved, thereby further enhancing the overall performance of the humidifier 1 and the fuel cell humidification system.

[0050] The water supply unit of this embodiment includes a water storage-type water vapor separator 3 and a water supply pipeline 304. The separator inlet 307 of the water storage-type water vapor separator 3 is connected to the water vapor outlet 203 of the fuel cell stack 2. A condensate outlet 302 is provided at the bottom of the water storage-type water vapor separator 3. The water supply pipeline 304 connects the condensate outlet 302 and the water supply inlet 107. Furthermore, a separator exhaust port 306 is provided at the top of the water storage-type water vapor separator 3. A separator overflow port 305 is also provided on the central sidewall of the water storage-type water vapor separator 3. This overflow port 305 can discharge overflowed water through a pipeline to an overflow collection device 301, such as a recovery tank or sewer.

[0051] By setting up a water storage type water vapor separator 3, full utilization of the water vapor discharged from the fuel cell stack 2 can be achieved; the condensed water generated by the running fuel cell stack 2 is used as the water source of the water supply unit, and after being separated by the water storage type water vapor separator 3, it is used in the humidifier 1, and then the air in the air supply unit is humidified, so that the condensed water discharged from the fuel cell stack 2 and the heat remaining in the condensed water are fully utilized and recovered, which helps to reduce the overall operating cost of the fuel cell stack 2.

[0052] Based on the above-mentioned configuration, it is preferred that the level of the condensate outlet 302 be set higher than the level of the top of the humidifier 1, and a control valve 303 be provided on the water supply line 304. Placing the water storage-type water vapor separator 3 at a higher position above the humidifier 1 allows the water in the water storage-type water vapor separator 3 to flow into the humidifier 1 by gravity, without the need for a water supply pump or other pumping device, which is beneficial to reducing the energy consumption of the system operation. By providing the control valve 303 on the water supply line 304, the water supply volume of the water supply unit can be adjusted in real time, thereby controlling the water level in the humidifier 1 at an appropriate level, which has a good effect on improving the evaporation performance of the humidifier 1 and the stability of the system operation.

[0053] To sum up, the fuel cell humidification system of this embodiment adopts a vacuum boiling type humidifier 1. By controlling the operating power of the vacuum pump 113, the vacuum degree of the inner cavity of the humidifier 1 can be changed, thereby changing the evaporation amount of water in the inner cavity of the humidifier 1; as the evaporation amount changes, the steam mixed in the air in the air supply unit changes accordingly; in this way, the operating state of the vacuum pump 113 can be adjusted in real time according to the operating conditions of the fuel cell stack 2, so as to control the humidity of the air supplied by the air supply unit to the fuel cell stack 2 within a suitable range, thereby achieving the purpose of improving the control effect of the fuel cell intake humidity.

[0054] Example 2

[0055] This embodiment relates to a fuel cell, on which the fuel cell humidification system provided in the first embodiment is provided.

[0056] In general, the fuel cell of this embodiment includes a fuel cell stack 2 and a fuel cell humidification system configured for the fuel cell stack 2. An exemplary overall structure of the fuel cell is as follows: Figure 1 The cathode side of the fuel cell stack 2 is provided with an air inlet 202 and a water vapor outlet 203 , which are used to connect to the above-mentioned fuel cell humidification system.

[0057] The anode side of the fuel cell stack 2 is provided with a hydrogen inlet 206 and a hydrogen outlet 207. The hydrogen inlet 206 is connected to the hydrogen source 201 via a hydrogen pipeline 205, which is also provided with a hydrogen supply valve 204 for on / off control. The hydrogen outlet 207 is connected to a hydrogen tail gas discharge pipeline, which is provided with a hydrogen tail valve 208 for on / off control. The tail end of the pipeline forms a hydrogen tail outlet 209.

[0058] Based on the above overall configuration, the working principle of the fuel cell of this embodiment is as follows:

[0059] like Figure 1 As shown, a hydrogen source 201 located outside the fuel cell stack 2 inputs hydrogen through a hydrogen supply valve 204 to the hydrogen inlet 206 of the fuel cell stack 2, where it then enters the fuel cell stack 2. Hydrogen exhaust gas after operation is discharged through a hydrogen exhaust pipeline at the hydrogen outlet 207. When the hydrogen exhaust valve 208 is opened, the exhaust gas is discharged to the outside through the hydrogen exhaust outlet 209. The hydrogen entering the fuel cell stack 2 reacts with moist air input from the air inlet 202 to generate electricity. This electricity also produces water. This water, along with the exhaust gas after operation, is discharged from the water exhaust outlet 203 and enters the separator inlet 307 of the water storage-type water vapor separator 3 for water vapor separation. The separated water is stored in the lower portion of the water storage-type water vapor separator 3. If too much liquid water is stored, it will overflow from the separator overflow outlet 305 into the overflow collection device 301. The relatively dry tail air is discharged to the outside from the separator exhaust port 306; the liquid water generated by separation is output from the condensate outlet 302 to the control valve 303. According to the water level detection inside the humidifier 1, once there is a lack of water, the control valve 303 is controlled to open, and the liquid water is then replenished into the humidifier 1 through the water replenishment pipeline 304.

[0060] Due to the operation of the vacuum pump 113, the upper part of the inner cavity of the humidifier 1 is always maintained in a negative pressure state. The magnitude of the negative pressure is determined by the operating state of the vacuum pump 113. The working principle and main functions of the entire fuel cell humidification system include the following parts:

[0061] Automatic water replenishment function: During operation, the water inside the lower housing 103 of the humidifier 1 will continuously boil, evaporate, and be consumed. Therefore, water needs to be continuously replenished. However, excessive water replenishment cannot be excessive, as this will cause vacuum liquid hammer, causing some water to enter and pass through the vacuum pump 113, thereby damaging the vacuum pump 113 or causing liquid water to directly enter the fuel cell stack 2. Therefore, during boiling, the liquid level sensor 109 will detect the water level inside the humidifier 1. When it detects that the water level is decreasing, the control valve 303 is opened. Due to the negative pressure inside the humidifier 1 and the gravity of the water body, water is automatically replenished into the humidifier 1. When the liquid level sensor 109 detects that the water replenishment is complete (reaching the set liquid level), the system controls the closing of the control valve 303, completing the water replenishment process. This ensures that the entire boiling process is carried out within a normal water level range.

[0062] Liquid-slugging prevention: In a fuel cell humidification system, liquid water entering the fuel cell stack 2 and vacuum pump 113 can affect the performance and lifespan of the system and its components. Therefore, during operation, the humidifier 1 should prevent liquid water from directly reaching the vacuum pump 113 at the top of the humidifier 1. To this end, the humidifier 1 is structurally designed with a liquid-slugging prevention microporous mesh 108 between the humidifier lower housing 103 and the humidifier upper housing 102. During operation, evaporated gas can pass through the microporous mesh 108, while liquid water is trapped within the inner cavity of the humidifier lower housing 103 beneath the microporous mesh 108.

[0063] Cooling and heat transfer function: The air sucked in from the air compressor inlet 402 is compressed by the air compressor 4 to form high-temperature and high-pressure compressed air, which is output from the air compressor outlet 403. At this time, the high-temperature and high-pressure gas cannot meet the requirements of the fuel cell system and must be cooled and humidified. During the process of liquid boiling, evaporation and gasification, the humidifier 1 needs to absorb a large amount of external vaporization heat. Therefore, when designing the humidifier 1, the high-temperature and high-pressure gas output by the air compressor 4 is transported to the humidifier air pipeline 101 located inside the humidifier 1 through the air compressor output pipeline 404. During the process of the high-temperature gas passing through the humidifier air pipeline 101 immersed in the liquid in the humidifier lower shell 103, the high-temperature gas exchanges heat with the liquid water in the humidifier lower shell 103. At the same time, through the heat conduction effect of the heat exchange fins 106 tightly pressed on the humidifier air pipeline 101, the heat in the high-temperature gas will be transferred to the liquid in the humidifier lower shell 103 more quickly. On the one hand, this reduces the temperature of the input high-temperature gas, and on the other hand, increases the temperature of the liquid inside the humidifier 1, which is beneficial to the boiling and evaporation of the liquid, and can improve the overall efficiency and working reliability of the system. The low-temperature dry gas after cooling is output through the air outlet 105 on the outer wall of the humidifier 1, and enters the water vapor mixing pipeline 407 through the low-temperature dry air output pipeline 405. The water vapor in the water vapor output pipeline 406 also enters the water vapor mixing pipeline 407. After the air and water vapor are mixed in the water vapor mixing pipeline 407, they are sent to the air input port 202 and enter the interior of the fuel cell stack 2 to react with hydrogen to generate electricity.

[0064] Boiling Evaporation Humidification Function: Fuel cell engines have different requirements for air input and humidity at different operating power levels. To best meet the air humidity requirements of the fuel cell stack under different operating conditions, the optimal humidification method is active control, that is, adjusting and controlling the humidity of the supplied air according to the different operating conditions of the fuel cell. Based on the operating conditions of the fuel cell engine, the humidifier 1 of the present invention measures the internal pressure (vacuum level) of the humidifier 1 via a cavity pressure sensor 111, the temperature of the steam in the inner cavity of the humidifier upper housing 102 via a cavity temperature sensor 114, and the temperature of the liquid in the humidifier lower housing 103 via a water temperature sensor 115. Based on a pre-set control strategy, the fuel cell engine's air humidity requirements are calculated, and the workload of the vacuum pump 113 is then controlled to maintain a stable negative pressure value detected by the cavity pressure sensor 111. By adjusting the negative pressure in the humidifier upper housing 102, the boiling level of the liquid inside the humidifier 1 is adjusted, thereby adjusting the amount of water vapor generated by the humidifier 1 to meet the air humidification requirements of the fuel cell engine system.

[0065] Because it uses a boiling evaporation humidification mode, the air entering the fuel cell is mixed and humidified entirely with water vapor, thus avoiding the potential risk of liquid water entering the fuel cell stack 2. Furthermore, because the humidifier 1 regulates the boiling level of the liquid by adjusting the internal cavity pressure, the amount of liquid boiling evaporation can be adjusted to a large extent according to the needs of the fuel cell system, thereby actively adjusting the humidity of the air entering the fuel cell stack 2 and meeting the air humidity requirements of the fuel cell under different operating conditions.

[0066] To sum up, the fuel cell of the utility model, its fuel cell humidification system adopts an active control method to control and adjust the humidity of the air entering the fuel cell stack 2, and at the same time effectively integrates and utilizes the heat energy in the entire air circuit, organically integrating them to form a new fuel cell boiling humidification technology solution, and has outstanding advantages such as low process structure setting cost, stable effect, long life, and easy maintenance; it has a significant effect on improving the power generation efficiency of the fuel cell system and reducing energy consumption, and can achieve the purpose of energy saving and emission reduction in system operation, and extend the service life of the fuel cell system.

[0067] The above description is merely a preferred embodiment of the present invention. The detailed configuration explanations, specific structural configuration examples, and assembly connection descriptions are provided for the purpose of providing sufficient disclosure to enable those skilled in the art to better implement the present invention. They are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A fuel cell humidification system, characterized in that: It includes a humidifier (1), an air supply unit, and a water supply unit; The water supply unit is connected to the water supply port (107) of the humidifier (1), the air supply unit is connected to the air input port (202) of the fuel cell stack (2), and the top of the humidifier (1) is provided with a steam outlet (112) connected to the air supply unit; A vacuum pump (113) is provided at the steam outlet (112). The running vacuum pump (113) can reduce the pressure in the inner cavity of the humidifier (1), so that the water replenished into the inner cavity through the water replenishment port (107) boils, and the boiling steam is merged into the air of the air supply unit through the steam outlet (112).

2. The fuel cell humidification system according to claim 1, characterized in that: The vacuum pump (113) is a diaphragm vacuum pump.

3. The fuel cell humidification system according to claim 1, characterized in that: The humidifier (1) comprises an upper shell (102) and a lower shell (103) of the humidifier which are buckled together to form the inner cavity, the water replenishment port (107) is provided on the lower shell (103) of the humidifier, the steam outlet (112) is provided on the top of the upper shell (102) of the humidifier, and a microporous mesh (108) is provided between the inner cavity of the upper shell (102) of the humidifier and the inner cavity of the lower shell (103) of the humidifier.

4. The fuel cell humidification system according to claim 1, wherein: The humidifier (1) is equipped with a liquid level sensor (109) for monitoring the water level in the inner cavity, and / or a safety discharge valve (110) is provided on the housing of the humidifier (1).

5. The fuel cell humidification system according to claim 1, characterized in that: The humidifier (1) is equipped with at least one of a water temperature sensor (115), a cavity temperature sensor (114), and a cavity pressure sensor (111); the water temperature sensor (115) is used to monitor the water temperature in the inner cavity, the cavity temperature sensor (114) is used to detect the temperature of the steam in the inner cavity, and the cavity pressure sensor (111) is used to detect the vacuum degree at the top of the inner cavity.

6. The fuel cell humidification system according to claim 1, characterized in that: The air supply unit comprises an air compressor (4), and an air compressor output pipeline (404), a humidifier air pipeline (101), and a water vapor mixing pipeline (407) sequentially connected between the air compressor (4) and the air input port (202); The humidifier air pipeline (101) is arranged at the bottom of the inner cavity, and the steam outlet (112) is connected to the water vapor mixing pipeline (407).

7. The fuel cell humidification system according to claim 6, characterized in that: A plurality of heat exchange fins (106) are arranged at intervals on the outer wall of the humidifier air pipeline (101).

8. The fuel cell humidification system according to any one of claims 1 to 7, characterized in that: The water supply unit includes a water storage type water vapor separator (3) and a water supply pipeline (304); The separator input port (307) of the water storage type water vapor separator (3) is connected to the water vapor outlet (203) of the fuel cell stack (2), and a condensate outlet (302) is provided at the bottom of the water storage type water vapor separator (3), and the water supply pipeline (304) is connected between the condensate outlet (302) and the water supply port (107).

9. The fuel cell humidification system according to claim 8, characterized in that: The level of the condensate outlet (302) is higher than the level of the top of the humidifier (1), and a control valve (303) is provided on the water supply pipeline (304).

10. A fuel cell, characterized in that: The fuel cell is provided with the fuel cell humidification system according to any one of claims 1 to 9.

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