Cathode system and fuel cell having the same

Abstract

The utility model discloses a cathode system and a fuel cell having the same, wherein the cathode system comprises a water distributor, a switching assembly and a humidity regulating assembly, wherein the humidity regulating assembly comprises a humidifier and a water applicator, wherein the humidifier is formed with a humidification pipeline and a moisture cavity, wherein the humidification pipeline is arranged in the moisture cavity and is suitable for connecting to an air inlet, wherein the humidification pipeline is configured such that water in the moisture cavity can penetrate into the humidification pipeline, wherein the moisture cavity has a moisture inlet and a moisture outlet, wherein the moisture inlet is suitable for connecting to an air outlet, wherein the moisture outlet is connected to a first inlet, wherein the water applicator is connected to a drainage outlet through a first branch and is used for applying water to the moisture cavity, wherein a fourth switching valve is arranged on the first branch, wherein the fourth switching valve is used for switching the connection or disconnection between the drainage outlet and the water applicator. According to the cathode system of the utility model embodiment, the humidifier and the water applicator cooperate with each other, thereby facilitating meeting the differentiated requirements of the cathode system for gas humidity under different states and improving the applicability of the cathode system.

Description

Technical Field

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

[0002] In related technologies, fuel cells are energy conversion devices that use hydrogen and oxygen in the air to generate electricity through electrochemical reactions. Fuel cells need to be matched with corresponding systems (such as cathode systems) to operate normally. However, in some technologies, the humidification scheme used in the cathode system fails to meet actual needs, which has a certain impact on the overall design of the cathode system. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a cathode system, wherein the cathode system cooperates with a humidifier and a water applicator to meet the differentiated requirements of the cathode system for gas humidity under different states, thereby improving the applicability of the cathode system.

[0004] The utility model also provides a fuel cell with a cathode system.

[0005] The cathode system according to the first embodiment of the utility model is used for the cathode side of the fuel cell, and the cathode side of the fuel cell has an air inlet and an air outlet. The cathode system includes: a water separator, the water separator is formed with a first inlet, an exhaust outlet and a drain outlet, and the water separator is used to separate air and water from the air discharged from the air outlet; a switching component, the switching component includes a first switching valve and a fourth switching valve, the first switching valve is arranged between the air outlet and the first inlet, and is used to switch the air outlet to be connected or disconnected with the first inlet; a humidity regulating component, the humidity regulating component includes a humidifier and a water applicator The humidifier is formed with a humidification pipeline and a moisture cavity, the humidification pipeline is arranged in the moisture cavity and is suitable for connecting to the air inlet, the humidification pipeline is constructed as follows: water in the moisture cavity can penetrate into the humidification pipeline, the moisture cavity has a moisture inlet and a moisture outlet, the moisture inlet is suitable for selectively connecting to the air outlet, the moisture outlet is connected to the first inlet, the water applicator is connected to the drain outlet through a first branch, and is used to apply water to the moisture cavity, the fourth switching valve is arranged on the first branch, and the fourth switching valve is used to switch the connection or disconnection between the drain outlet and the water applicator.

[0006] According to the cathode system of the embodiment of the utility model, the cathode system can be switched to a suitable working mode, and the humidifier and the water applicator can cooperate with each other to humidify the gas flowing into the air inlet so that the humidity regulating component can adapt to the humidity requirements of different working states of the cathode system to ensure that the gas flowing into the cathode side of the fuel cell from the air inlet maintains a suitable humidity.

[0007] In some embodiments, the switching component also includes a third switching valve and a liquid level detector. The third switching valve is connected to the drain outlet through a second branch and has an adjustable opening. The liquid level detector is used to detect the liquid level height in the water divider. The liquid level detector is communicatively connected to the third switching valve.

[0008] In some embodiments, the cathode system also includes: a mixing device, the mixing device includes multiple second inlets and a mixing outlet, the multiple second inlets include a gas inlet and a liquid inlet, the gas inlet is connected to the exhaust outlet, the liquid inlet is connected to the drain outlet, and the mixing outlet is suitable for connecting to the outside to discharge the gas and liquid in the mixing device; the switching component also includes a third switching valve, the third switching valve is connected between the drain outlet and the liquid inlet through a second branch and is used to switch the connection or disconnection between the drain outlet and the liquid inlet.

[0009] In some embodiments, the cathode system further includes a first muffler disposed at the mixing outlet.

[0010] In some embodiments, the switching assembly further includes a second switching valve, which is disposed downstream of the exhaust outlet and has an adjustable opening.

[0011] In some embodiments, the cathode system also includes: an air supply device, the air supply device includes an air compressor and a turbo expander connected to each other, the air compressor is formed with an air inlet and an exhaust port, the air inlet is suitable for connecting to the outside world, the exhaust port is connected to the humidification pipeline through an air inlet pipeline, the turbo expander has an air inlet end and an exhaust end, the air inlet end is connected to the second switching valve through a first exhaust pipeline, and the exhaust end is suitable for connecting to the outside world.

[0012] In some embodiments, the cathode system also includes: a first valve body, the first valve body is arranged on the intake pipeline and is formed with a first inlet, a first outlet and a second outlet, each of the first outlet and the second outlet can be selectively connected to the first inlet, the first inlet is connected to the exhaust port, the first outlet is connected to the humidification pipeline, and the second outlet is connected to the intake end through the second exhaust pipeline; and / or, a second valve body and a third valve body, the second valve body is formed with a second inlet, a third outlet and a fourth outlet, the second inlet is connected to the exhaust end, the third outlet is suitable for connecting with the outside world, the third valve body includes a third inlet, a fourth inlet and a fifth outlet, the third inlet is suitable for connecting with the outside world, the fourth inlet is connected to the fourth outlet, and the fifth outlet is connected to the intake port.

[0013] In some embodiments, the cathode system includes a first switching valve, a second switching valve and a third switching valve, and has at least one of a standby state, a first operating state, a second operating state and a purge state. In the standby state, the first inlet is disconnected from the first outlet, the first inlet is connected to the second outlet, the first switching valve, the second switching valve and the third switching valve are all closed, the second inlet is connected to the third outlet, the second inlet is disconnected from the fourth outlet, the third inlet is connected to the fifth outlet, and the fourth inlet is disconnected from the fifth outlet; in the first operating state, the first outlet and the second outlet are respectively connected to the first inlet, the first switching valve and the second switching valve are both opened, the second inlet is connected to the third outlet, the second inlet is disconnected from the fourth outlet, and the third inlet is connected to the fifth outlet. The first inlet is connected to the fifth outlet, the fourth inlet is disconnected from the fifth outlet, and the water applicator is closed; in the second operating state, the first inlet is connected to the first outlet, the first inlet is disconnected from the second outlet, the first switching valve and the second switching valve are both opened, the second inlet is connected to the third outlet, the second inlet is disconnected from the fourth outlet, the third inlet is connected to the fifth outlet, the fourth inlet is disconnected from the fifth outlet, and the water applicator is opened; in the purge state, the first inlet is connected to the first outlet, the first inlet is disconnected from the second outlet, the first switching valve and the second switching valve are both opened, the second inlet is disconnected from the third outlet, the second inlet is connected to the fourth outlet, the third inlet and the fourth inlet are respectively connected to the fifth outlet, and the water applicator is closed.

[0014] In some embodiments, the cathode system includes a second valve body and a third valve body, and further includes a filter and a flow meter, wherein the filter is connected between the fifth outlet and the air inlet, and the flow meter is connected between the filter and the air inlet.

[0015] The fuel cell according to the second aspect of the present invention comprises the cathode system according to the first aspect of the present invention.

[0016] The fuel cell according to the embodiment of the utility model can improve the performance of the fuel cell by adopting the above-mentioned cathode system.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 is a schematic diagram of a cathode system according to some embodiments of the present invention.

[0020] Reference numerals:

[0021] Cathode system 100, air inlet 10a, air outlet 10b,

[0022] The first branch 9a, the second branch 9b, the intake pipe 9c, the first exhaust pipe 9d, the second exhaust pipe 9e,

[0023] Water separator 1, first inlet 11, exhaust outlet 12, drain outlet 13,

[0024] Switching assembly 2, first switching valve 21, second switching valve 22, third switching valve 23, fourth switching valve 24, fifth switching valve 25,

[0025] Humidity adjustment component 3, humidifier 31, humidification pipeline 311, moisture cavity 312, moisture inlet 312a, moisture outlet 312b, water applicator 32,

[0026] Air supply device 4, air compressor 41, air inlet 41a, exhaust port 41b, turbo expander 42, air inlet end 42a, exhaust end 42b,

[0027] first valve body 5, first inlet 51, first outlet 52, second outlet 53,

[0028] The second valve body 6, the second inlet 61, the third outlet 62, the fourth outlet 63,

[0029] The third valve body 7, the third inlet 71, the fourth inlet 72, the fifth outlet 73,

[0030] Liquid level detector 81 , intercooler 82 , filter 83 , flow meter 84 , second muffler 85 , first muffler 86 , mixing device 87 , mixing outlet 87 a , gas inlet 87 b , liquid inlet 87 c , humidity sensor 88 , pressure sensor 89 , and temperature sensor 90 . DETAILED DESCRIPTION

[0031] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0032] The disclosure below provides many different embodiments or examples for realizing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the utility model. In addition, the utility model can repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the utility model provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the applicability of other processes and / or the use of other materials.

[0033] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0034] Hereinafter, referring to the accompanying drawings, a cathode system 100 according to an embodiment of the present invention will be described. The cathode system 100 is used for the cathode side of a fuel cell, and the cathode side of the fuel cell has an air inlet 10a and an air outlet 10b.

[0035] like Figure 1The cathode system 100 includes a water separator 1 and a switching assembly 2. The water separator 1 is formed with a first inlet 11, an exhaust outlet 12 and a drain outlet 13. The first inlet 11 is suitable for selectively connecting to the air outlet 10b. When the first inlet 11 is connected to the air outlet 10b, the gas and liquid discharged from the air outlet 10b on the cathode side of the fuel cell flow into the water separator 1 through the first inlet 11. The water separator 1 is used to separate the gas (including gaseous water and liquid water, etc.) discharged from the air outlet 10b, so that the separated gas is discharged from the exhaust outlet 12 and the separated liquid is discharged from the drain outlet 13. The switching assembly 2 includes a first switching valve 21 and a fourth switching valve 24. The first switching valve 21 is arranged between the air outlet 10b and the first inlet 11, and the first switching valve 21 is used to switch The air outlet 10b is connected or disconnected with the first inlet 11 to control the connection between the air outlet 10b and the first inlet 11. When the first switching valve 21 disconnects the connection between the air outlet 10b and the first inlet 11, the gas generated on the cathode side cannot flow into the water separator 1 through the first inlet 11. At this time, the cathode side of the fuel cell can be sealed at the air outlet 10b, which is beneficial to improve the sealing of the cathode side of the fuel cell (for example, the sealing of the cathode cavity in the fuel cell stack), and can prevent air from entering the fuel cell to a certain extent, causing the electrochemical reaction to continue to occur in the fuel cell, thereby improving the reliability of the fuel cell; when the first switching valve 21 connects the air outlet 10b with the first inlet 11, the air outlet 10b can discharge the air after the reaction on the cathode side to the water separator 1.

[0036] The cathode system 100 also includes a humidity regulating component 3, which includes a humidifier 31 and a water applicator 32. The humidifier 31 is formed with a humidification pipeline 311 and a moisture cavity 312. The humidification pipeline 311 is arranged in the moisture cavity 312 and is suitable for connecting to the air inlet 10a. The humidification pipeline 311 is constructed as follows: the water in the moisture cavity 312 can penetrate into the humidification pipeline 311, and the humidification pipeline 311 can humidify the gas (such as air) flowing into the fuel cell, that is, the humidification pipeline 311 is located upstream of the air inlet 10a, and the gas first flows through the humidification pipeline 311 to achieve humidification, and then flows to the cathode side of the fuel cell, so that the gas flowing in from the air inlet 10a has a suitable humidity, so that the electrolyte membrane in the fuel cell has a suitable wet state, which can improve the performance and efficiency of the fuel cell. The moisture chamber 312 has a moisture inlet 312a and a moisture outlet 312b. The moisture inlet 312a is suitable for being selectively connected to the air outlet 10b, and the moisture outlet 312b is connected to the first inlet 11. Then, the humidified gas after the reaction in the fuel cell can flow into the moisture chamber 312, so that the humidification pipeline 311 can utilize the water in the humidified gas after the reaction, that is, the water in the humidified gas after the reaction can penetrate into the humidification pipeline 311, so that the humidifier 31 can utilize the water in the gas discharged from the air outlet 10b, which can ensure that the humidifier 31 has a suitable humidification capacity, so that the humidifier 31 can better humidify the gas flowing into the cathode side of the fuel cell from the air inlet 10a.

[0037] It can be understood that the humidifier 31 is located between the water separator 1 and the air outlet 10b, that is, the moisture inlet 312a of the humidifier 31 can be selectively connected to the air outlet 10b, and the moisture outlet 312b of the humidifier 31 is connected to the first inlet 11 of the water separator 1. The reacted humidified gas flowing out of the air outlet 10b first passes through the moisture cavity 312, and then flows into the water separator 1. The humidifier 31 first utilizes part of the water in the reacted humidified gas, and then the water separator 1 separates the reacted humidified gas into gas and water.

[0038] Optionally, the humidification pipeline 311 includes a plurality of water-permeable permeable membrane tubes arranged side by side, and the same end of the plurality of permeable membrane tubes is connected to the air inlet 10a, thereby improving the humidification effect of the humidification pipeline 311 and improving the humidification efficiency of the humidification pipeline 311. It is understandable that the permeable membrane tube can achieve unidirectional permeation of water, that is, the water in the moisture cavity 312 permeates into the permeable membrane tube to achieve the humidification effect of the humidification pipeline 311.

[0039] Among them, the water applicator 32 is connected to the drain outlet 13 through the first branch 9a, and the water separated by the water separator 1 can flow to the water applicator 32 through the first branch 9a, and is used to apply water to the moisture cavity 312, so that the water applicator 32 can use the water separated by the water separator 1 to enhance the humidity in the moisture cavity 312, thereby improving the humidification effect of the humidification pipeline 311 on the gas flowing to the air inlet 10a, that is, the water applicator 32 and the humidifier 31 can humidify the gas flowing to the air inlet 10a, improve the humidification effect of the gas flowing to the air inlet 10a, and at the same time, can make full use of the water (that is, tail water) generated after the reaction in the fuel cell (such as the fuel cell stack). Optionally, the water applicator 32 is used to apply water to the moisture chamber 312, and the water applicator 32 can apply water to the moisture chamber 312 alone to increase the humidity of the moisture chamber 312, or the water applicator 32 can apply water to the moisture chamber 312 and the humidification pipeline 311 at the same time. For example, the water applicator 32 can use the water generated after the reaction in the fuel cell to spray water into the moisture chamber 312 to increase the humidity in the moisture chamber 312, thereby increasing the amount of water infiltrated from the moisture chamber 312 to the humidification pipeline 311, so as to increase the humidification strength of the humidification pipeline 311.

[0040] In addition, the fourth switching valve 24 is provided on the first branch 9a, and the fourth switching valve 24 is used to switch the connection or disconnection between the drainage outlet 13 and the water applicator 32. Thus, the fourth switching valve 24 can control the connection and disconnection of the first branch 9a, that is, can control the connection or disconnection between the drainage outlet 13 and the water applicator 32, so that the cathode system 100 can control the water applicator 32 in real time, and the applicability of the cathode system 100 can be improved.

[0041] Optionally, the opening of the fourth switching valve 24 is adjustable (for example, the opening of the fourth switching valve 24 is adjusted by PID method), so that the amount of water flowing from the drainage outlet 13 to the water applicator 32 can be adjusted, so as to facilitate further direct control of the water spraying amount of the water applicator 32, that is, the humidification intensity of the moisture cavity 312 by the water applicator 32 can be adjusted, so as to adjust the humidification effect of the humidity regulating component 3 to adapt to the air intake volume of the air inlet 10a to ensure that the gas is at a suitable humidity.

[0042] It can be understood that the cathode system 100 has a first working mode and a second working mode. In the first working mode, one of the humidifier 31 and the water applicator 32 works alone, and the humidifier 31 or the water applicator 32 can humidify the gas flowing into the fuel cell to adapt to the humidity requirement of the cathode side of the fuel cell (the smaller humidity requirement of the cathode side of the fuel cell), so that the electrolyte membrane in the fuel cell has a suitable humidification state. For example, in the first working mode, when the humidifier 31 is working, the humidification pipeline 311 can use the water in the humidification chamber 312 to humidify the gas flowing into the humidification pipeline 311, or, when the water applicator 32 is working, the water applicator 32 can use the water in the water distributor to apply water to the humidification pipeline 311 to humidify the gas flowing into the humidification pipeline 311. Optionally, in the first working mode, the humidifier 31 and the water applicator 32 can work alternately, and the time for which one of the humidifier 31 and the water applicator 32 works alone is not limited, so that the cathode system 100 can effectively utilize the water in the water distributor 1 through the water applicator 32, which is conducive to reducing costs.

[0043] In the second working mode, the humidifier 31 and the water applicator 32 work simultaneously, and the humidifier 31 and the water applicator 32 jointly humidify the gas flowing into the humidification pipeline 311, which can increase the humidification intensity of the gas flowing into the fuel cell to adapt to the humidity demand on the cathode side of the fuel cell (the larger humidity demand on the cathode side of the fuel cell), so that the electrolyte membrane in the fuel cell has a suitable wet state.

[0044] Thus, the cathode system 100 can adapt to the humidity demand of the fuel cell in a suitable working mode (the first working mode or the second working mode), and the humidifier 31 and the water applicator 32 can cooperate with each other to humidify the gas flowing to the air inlet 10a, for example, the humidifier 31 or the water applicator 32 works alone, or the humidifier 31 and the water applicator 32 work together, etc., so that the humidity adjustment component 3 can realize the control of different humidification amounts to adapt to the differentiated requirements of the fuel cell for gas humidity under different working conditions, so as to ensure that the gas flowing into the cathode side of the fuel cell from the air inlet 10a maintains a suitable humidity. For example, when the fuel cell humidification demand is relatively small (for example, the fuel cell is in a relatively low power operating state), the cathode system 100 is in a first operating mode, and the humidifier 31 or the water applicator 32 can be used alone to meet the humidity demand of the gas flowing into the fuel cell from the air inlet 10a. When the fuel cell humidification demand is relatively large (for example, the fuel cell is in a relatively high power operating state), the cathode system 100 is in a second operating mode, and the humidifier 31 and the water applicator 32 work together to meet the humidity demand of the gas flowing into the cathode side of the fuel cell from the air inlet 10a.

[0045] In some technologies, the humidification scheme adopted in the cathode system is a humidifier or a water applicator, and the humidification amount cannot be adjusted in size. When the cathode system is in a high-power working state, the cathode side of the fuel cell has a large demand for gas humidification. In the scheme of using a humidifier alone, the humidifier occupies a large space, which will affect the volume-power ratio of the cathode system or the fuel cell, and is not conducive to the application in corresponding equipment (such as vehicles), making the cathode system or the fuel cell less suitable for the assembly space of the corresponding equipment; in the scheme of using a water applicator alone, the low-voltage power consumption of the fuel cell will increase, and the output power and output efficiency of the cathode system at rated power will be reduced, which will place higher requirements on the low-voltage power distribution of the corresponding equipment. In an embodiment of the present application, the cathode system 100 can be switched to a suitable working mode, that is, the cathode system 100 adopts an arrangement scheme in which the humidifier 31 and the water applicator 32 work together. When the cathode system 100 is in a relatively low-power working state, the cathode system 100 switches to a first working mode, and the cathode system 100 can use the humidifier 31 or the water applicator 32 alone to meet the gas humidity requirement on the cathode side of the fuel cell. When the cathode system 100 is in a relatively high-power working state (for example, rated power), the cathode system 100 switches to a second working mode, and the humidifier 31 and the water applicator 32 work together to humidify to meet the gas humidity requirement on the cathode side of the fuel cell, thereby correspondingly reducing the size of the humidifier 31 and / or the water applicator 32, and reducing the power of the water applicator 32, which is beneficial to improving the volume power density ratio of the cathode system 100, that is, the output power of the cathode system 100 can be increased, and the low-voltage power distribution requirements in the corresponding equipment can be reduced.

[0046] Optionally, the types of the first switching valve 21 and the fourth switching valve 24 are not limited, for example, the first switching valve 21 and the fourth switching valve 24 are back pressure valves. It is understandable that the opening of the first switching valve 21 is adjustable or the opening of the first switching valve 21 is not adjustable. Exemplarily, the opening of the first switching valve 21 is adjusted by PID adjustment; of course, it can also be adjusted manually.

[0047] According to the cathode system 100 of the embodiment of the utility model, the cathode system 100 can be switched to a suitable working mode, and the humidifier 31 and the water applicator 32 can cooperate with each other to humidify the gas flowing into the air inlet 10a, so that the humidity regulating component 3 can adapt to the differentiated requirements of the cathode system 100 for gas humidity in different working states, so as to ensure that the gas flowing into the cathode side of the fuel cell from the air inlet 10a maintains a suitable humidity.

[0048] It should be noted that the humidifier 31 can use the water in the gas after the reaction at the air outlet 10b to enable the humidifier 31 to have a humidification capability. When the cathode system 100 starts working for the first time, the cathode system 100 is running slowly at a lower power. At this time, the gas flowing into the air inlet 10a does not need to be humidified, and the cathode side requirements of the fuel cell are also met. The humidified gas after the fuel cell reaction flows into the humidifier 31, that is, the humidifier 31 can use the water in the gas after the reaction to increase the humidity of the wet gas cavity 312, so that the humidifier 31 has a humidification capability.

[0049] In some embodiments, the switching component 2 also includes a third switching valve 23 and a liquid level detector 81. The third switching valve 23 is connected to the drain outlet 13 through the second branch 9b and has an adjustable opening. The liquid level detector 81 is used to detect the liquid level height in the water distributor 1. The liquid level detector 81 is communicated with the third switching valve 23.

[0050] Specifically, Figure 1 As shown, the switching component 2 also includes a third switching valve 23, which is connected to the drain outlet 13 through the second branch 9b and has an adjustable opening (for example, the opening of the third switching valve 23 is adjusted by a PID method), so that the third switching valve 23 can realize the on-off of the second branch 9b, and can adjust the drainage volume of the water in the water distributor 1 from the drain outlet 13 to the second branch 9b (for example, the second branch 9b is suitable for connecting to the outside world, and the third switching valve 23 can adjust the drainage volume of the water distributor 1 to the outside world).

[0051] Among them, the first switching valve 21 and the third switching valve 23 are arranged downstream of the air outlet 10b. When the first switching valve 21 and the third switching valve 23 are in a closed state, that is, the first switching valve 21 disconnects the connection between the air outlet 10b and the first inlet 11, and the third switching valve 23 disconnects the connection between the second branch 9b, the sealing performance at the air outlet 10b can be improved, that is, the two-level sealing performance on the cathode side of the fuel cell can be achieved, which is beneficial to enhancing the sealing performance of the air outlet 10b, and to a certain extent, avoiding air from entering the fuel cell through the air outlet 10b, thereby improving the reliability of the fuel cell.

[0052] The cathode system 100 further includes a liquid level detector 81, which is used to detect the liquid level height in the water separator 1, and the liquid level detector 81 is connected to the third switching valve 23 in communication. Thus, the liquid level detector 81 can obtain the liquid level height in the water separator 1, so that the cathode system 100 can adjust the opening of the third switching valve 23 according to the value fed back by the liquid level detector 81, so as to control the amount of water in the water separator 1 by adjusting the drainage amount of the water separator 1, so that the amount of water in the water separator 1 is kept at a suitable liquid level height, so that the stored water can seal the drainage outlet 13, and to a certain extent, it can prevent the outside air from entering the water separator 1 through the drainage outlet 13, and can prevent the gas in the water separator 1 from being discharged from the drainage outlet 13, that is, it is ensured that the drainage outlet 13 is drained but not exhausted, so that all the gas in the water separator 1 (for example, all the tail exhaust of the fuel cell) is discharged from the exhaust outlet 12. Secondly, the third switching valve 23 cooperates with the liquid level detector 81 to store an appropriate amount of water in the water distributor 1 to keep the water applicator 32 working normally, so that the water applicator 32 can enhance the humidification effect on the gas flowing into the fuel cell from the air inlet 10a.

[0053] Optionally, the first branch 9a and the second branch 9b are connected to the drain outlet 13 of the water divider 1, and there is no interference between the first branch 9a and the second branch 9b. The water in the water divider 1 can flow to the first branch 9a and not flow to the second branch 9b, or flow to the second branch 9b and not flow to the first branch 9a, or flow to the first branch 9a and the second branch 9b respectively.

[0054] In some embodiments, Figure 1 As shown, the cathode system 100 further includes a mixing device 87, which includes a plurality of second inlets and a mixing outlet 87a, wherein the plurality of second inlets include a gas inlet 87b and a liquid inlet 87c, wherein the gas inlet 87b is connected to the exhaust outlet 12, and the liquid inlet 87c is connected to the drain outlet 13, and the mixing outlet 87a is adapted to be connected to the outside to discharge the gas and liquid in the mixing device 87. Thus, the mixing device 87 can achieve smooth discharge of gas and liquid.

[0055] The switching assembly 2 also includes a third switching valve 23, which is connected between the drain outlet 13 and the liquid inlet 87c through the second branch 9b and is used to switch the connection or disconnection between the drain outlet 13 and the liquid inlet 87c, so that the third switching valve 23 controls the discharge of water in the water distributor 1 to ensure that the liquid level height in the water distributor 1 is within an appropriate range.

[0056] In some embodiments, Figure 1 As shown, the cathode system 100 further includes a first muffler 86, which is disposed at the mixing outlet 87a, and can reduce the noise of the exhaust gas of the mixing device 87 and improve the comfort.

[0057] In some embodiments, Figure 1 As shown, the switching assembly 2 further includes a second switching valve 22, which is arranged downstream of the exhaust outlet 12 and has an adjustable opening. Thus, the second switching valve 22 can control the on-off of the downstream side of the exhaust outlet 12. When the second switching valve 22 disconnects the exhaust outlet 12 from the downstream flow path, the sealing of the exhaust outlet 12 can be achieved, which is beneficial to improve the sealing of the air outlet 10b, and can further prevent air from entering the cathode side of the fuel cell from the air outlet 10b, effectively protecting the fuel cell; when the second switching valve 22 connects the exhaust outlet 12 with the downstream flow path, the gas separated by the water separator 1 flows downstream through the exhaust outlet 12, and the amount of gas flowing downstream from the exhaust outlet 12 can be adjusted.

[0058] Among them, the second switching valve 22 is arranged downstream of the exhaust outlet 12 and the opening is adjustable. The second switching valve 22 can adjust the amount of gas flowing from the exhaust outlet 12 to the downstream, so that the second switching valve 22 can adjust the air pressure in the water distributor 1, that is, it can adjust the water pressure flowing from the first branch 9a to the water applicator 32, and can adaptively adjust the water spraying amount of the water applicator 32, so that the water applicator 32 can further adapt to the humidity requirement of the cathode side of the fuel cell, so that the opening of the second switching valve 22 can be adjusted to adjust the water spraying amount of the water applicator 32 to ensure that the gas flowing into the fuel cell from the air inlet 10a is at a suitable humidity. For example, when the second switching valve 22 is at a relatively small opening, the air pressure in the water distributor 1 is relatively large, and the water pressure flowing from the first branch 9a to the water applicator 32 is relatively large, that is, the water spraying amount of the water applicator 32 is relatively large at this time, thereby enhancing the humidification effect on the gas flowing into the fuel cell from the air inlet 10a, so that the humidity regulating component 3 can adapt to the cathode system 100 being in a relatively high-power working state (for example, the air intake amount of the air inlet 10a on the cathode side is relatively large at this time); when the second switching valve 22 is at a relatively large opening, the air pressure in the water distributor 1 is relatively small, so that the water pressure flowing from the first branch 9a to the water applicator 32 is relatively small, that is, the water spraying amount of the water applicator 32 is relatively small at this time, thereby reducing the humidification effect on the gas flowing into the fuel cell from the air inlet 10a, so that the humidity regulating component 3 can adapt to the cathode system 100 being in a relatively low-power working state (for example, the air intake amount of the air inlet 10a on the cathode side is relatively small at this time).

[0059] Therefore, the second switching valve 22 can adjust the amount of gas flowing from the exhaust outlet 12 to the downstream, so that the air pressure in the water distributor 1 can be adjusted, that is, the water pressure flowing from the first branch 9a to the water applicator 32 can be adjusted, and the water spraying amount of the water applicator 32 can be adaptively adjusted so that the water applicator 32 can adapt to the humidity requirement of the cathode side of the fuel cell, so that the water spraying amount of the water applicator 32 can be adjusted by adjusting the opening of the second switching valve 22, so as to further enhance the cathode system 100's ability to regulate gas humidity, so as to ensure that the gas flowing into the fuel cell from the air inlet 10a is at a suitable humidity.

[0060] Optionally, the first switching valve 21 and the second switching valve 22 are located downstream of the air outlet 10b. When the first switching valve 21 and the second switching valve 22 are in a closed state, that is, the first switching valve 21 disconnects the connection between the air outlet 10b and the first inlet 11, and the second switching valve 22 disconnects the connection between the exhaust outlet 12 and the downstream flow path, the sealing performance at the air outlet 10b can be improved, that is, the two-level sealing of the cathode side of the fuel cell can be achieved, which is beneficial to enhancing the sealing performance of the air outlet 10b, and to a certain extent avoiding air from entering the fuel cell through the exhaust flow path at the air outlet 10b, thereby improving the reliability of the fuel cell.

[0061] Optionally, the type of the second switching valve 22 is not limited, for example, the second switching valve 22 is a back pressure valve. It is understandable that the opening of the second switching valve 22 is adjustable or the opening of the second switching valve 22 is not adjustable. Exemplarily, the opening of the second switching valve 22 is adjusted by PID adjustment; of course, it can also be adjusted manually.

[0062] In some embodiments, Figure 1 As shown, the switching component 2 also includes a fifth switching valve 25, which is arranged between the air inlet 10a and the humidification pipeline 311 of the humidifier 31, and is used to switch the connection or disconnection between the air inlet 10a and the humidifier 31, so that the fifth switching valve 25 can control the connection and disconnection between the air inlet 10a and the humidifier 31, which is convenient for controlling whether the humidified gas enters the cathode side of the fuel cell, that is, it can control the operation of the fuel cell.

[0063] Optionally, the opening degree of the fifth switching valve 25 (eg, the intake throttle valve) is adjustable (eg, the opening degree of the fifth switching valve 25 is adjusted by a PID method).

[0064] In some embodiments, Figure 1As shown, the switching assembly 2 also includes a second switching valve 22, which is arranged downstream of the exhaust outlet 12 and has an adjustable opening. The cathode system 100 also includes an air supply device 4, which includes an air compressor 41 and a turbo expander 42 that are interconnected. The air compressor 41 is formed with an air inlet 41a and an exhaust port 41b. The air inlet 41a is suitable for connecting to the outside world, and the exhaust port 41b is connected to the humidification pipeline 311 through the air inlet pipeline 9c. In this way, when the air compressor 41 is working, the outside air enters the air compressor 41 through the air inlet 41a and flows to the humidification pipeline 311 through the air inlet pipeline 9c. The turbo expander 42 has an air inlet end 42a and an exhaust end 42b. The air inlet end 42a is connected to the second switching valve 22 through the first exhaust pipeline 9d, and the exhaust end 42b is suitable for connecting to the outside world. In this way, the second switching valve 22 can switch the connection or disconnection between the exhaust outlet 12 and the intake end 42a. At the same time, the second switching valve 22 can also control and adjust the amount of gas flowing from the exhaust outlet 12 to the turbo expander 42 through the first exhaust pipeline 9d.

[0065] Therefore, when the second switching valve 22 is switched to connect the exhaust outlet 12 with the intake end 42a, the turbo expander 42 can utilize the gas separated by the water separator 1 to do work, that is, utilize the tail gas to provide partial power for the air compressor 41, thereby reducing the power consumption of the air compressor 41 and realizing the effective utilization of the gas after the fuel cell reaction.

[0066] Optionally, the switching assembly 2 further includes a third switching valve 23, which is connected to the drain outlet 13 through the second branch 9b and has an adjustable opening; the cathode system 100 further includes a liquid level detector 81, which is used to detect the liquid level in the water separator 1, and the liquid level detector 81 is in communication connection with the third switching valve 23. Thus, the liquid level detector 81 cooperates with the third switching valve 23, and adjusts the opening of the third switching valve 23 to store a suitable amount of water in the water separator 1, so that the stored water can seal the drain outlet 13, so that the drain outlet 13 can only drain water but not exhaust gas, and all the gas discharged from the air outlet 10b can flow to the turbo expander 42, so that the maximum recycling of the gas after the fuel cell reaction can be achieved, and the efficiency of the fuel cell can be improved.

[0067] In some embodiments, Figure 1As shown, the cathode system 100 also includes a first valve body 5, which is arranged on the intake pipe 9c and is formed with a first inlet 51, a first outlet 52 and a second outlet 53, the first inlet 51 is connected to the exhaust port 41b, the first outlet 52 is connected to the humidification pipe 311, and the second outlet 53 is connected to the intake end 42a through the second exhaust pipe 9e; and / or, the cathode system 100 also includes a second valve body 6 and a third valve body 7, the second valve body 6 is formed with a second inlet 61, a third outlet 62 and a fourth outlet 63, the second inlet 61 is connected to the exhaust end 42b, the third outlet 62 is suitable for connecting with the outside, the third valve body 7 includes a third inlet 71, a fourth inlet 72 and a fifth outlet 73, the third inlet 71 is suitable for connecting with the outside, the fourth inlet 72 is connected to the fourth outlet 63, and the fifth outlet 73 is connected to the intake port 41a.

[0068] In some examples, such as Figure 1 As shown, the cathode system 100 further includes a first valve body 5 (e.g., a three-way valve), which is disposed on the air intake pipeline 9c and is formed with a first inlet 51, a first outlet 52, and a second outlet 53. Each of the first outlet 52 and the second outlet 53 can be selectively connected to the first inlet 51, the first inlet 51 is connected to the exhaust port 41b, the first outlet 52 is connected to the humidification pipeline 311, and the second outlet 53 is connected to the air intake end 42a through the second exhaust pipeline 9e. Thus, the first valve body 5 can have a variety of working modes, such as the first inlet 51 is connected to the first outlet 52, and the first inlet 51 is not connected to the second outlet 53; or the first inlet 51 is connected to the second outlet 53, and the first inlet 51 is not connected to the first outlet 52; or the first inlet 51 is connected to the first outlet 52, and the first inlet 51 is connected to the second outlet 53; or the first inlet 51 is connected to the first outlet 52, and the first inlet 51 is connected to the second outlet 53; or the first inlet 51 is not connected to the first outlet 52, and the first inlet 51 is not connected to the second outlet 53, etc.

[0069] Exemplarily, when the air compressor 41 is working, the first inlet 51 is connected with the first outlet 52, and the first inlet 51 is not connected with the second outlet 53. At this time, the air inhaled by the air compressor 41 flows from the exhaust port 41b to the first outlet 52 and flows into the humidification pipeline 311. The air is humidified by the humidity adjustment component 3 and flows to the air inlet 10a; or, the first inlet 51 is connected with the first outlet 52, and the first inlet 51 is connected with the second outlet 53. At this time, a part of the air inhaled by the air compressor 41 flows from the exhaust port 41b to the first outlet 52 and flows to the humidification pipeline 311, and the other part of the air flows from the exhaust port 41b to the second outlet 53 and flows to the air inlet end 42a.

[0070] It can be seen that when the first inlet 51 of the first valve body 5 is connected to the first outlet 52, and the first inlet 51 is connected to the second outlet 53, the air compressor 41 is working, and part of the air discharged by the air compressor 41 can flow to the air inlet end 42a through the second exhaust pipeline 9e (for example, the connection between the second outlet 53 and the first inlet 51 can reduce the pressure in the air compressor 41, so that the air compressor 41 can be in a suitable air pressure range). Therefore, when the fuel cell meets the air flow demand of the air compressor 41 to the air inlet 10a, the connection between the second outlet 53 and the first inlet 51 can effectively reduce the occurrence of surge of the air compressor 41. Secondly, the airflow from the first inlet 51 to the second outlet 53 flows to the air inlet end 42a through the second exhaust pipeline 9e, so that the turbo expander 42 can use the gas diverted from the first valve body 5 to do work, so as to provide part of the power for the operation of the air compressor 41, thereby reducing the power consumption of the air compressor 41.

[0071] Optionally, the opening of the first valve body 5 is adjustable (for example, the opening of the first valve body 5 is adjusted by PID method), for example, the opening of the first outlet 52 and the second outlet 53 are adjustable, so that the opening of the first outlet 52 and the second outlet 53 can be controlled, which facilitates the precise adjustment of the gas flow rate flowing out of the first outlet 52 and the second outlet 53, so that the opening of the first valve body 5 can be adjusted to better adapt to the power of the air compressor 41 (for example, when the air compressor 41 has a higher power, the opening of the second outlet 53 is larger; when the air compressor 41 has a lower power, the opening of the second outlet 53 is smaller), so as to reduce the occurrence of surge in the air compressor 41.

[0072] Optionally, in other embodiments, the first valve body 5 is arranged on the air intake pipe 9c and is formed with a first inlet 51, a first outlet 52 and a second outlet 53, the first inlet 51 is connected to the exhaust port 41b, the first outlet 52 is connected to the humidification pipe 311, and the second outlet 53 is suitable for connecting with the outside.

[0073] In some examples, such as Figure 1As shown, the second valve body 6 (e.g., a three-way valve) and the third valve body 7 (e.g., a three-way valve), the second valve body 6 is formed with a second inlet 61, a third outlet 62, and a fourth outlet 63, the second inlet 61 is connected to the exhaust end 42b, the third outlet 62 is suitable for connecting to the outside, the third valve body 7 includes a third inlet 71, a fourth inlet 72, and a fifth outlet 73, the third inlet 71 is suitable for connecting to the outside, the fourth inlet 72 is connected to the fourth outlet 63, and the fifth outlet 73 is connected to the air inlet 41a. In this way, the gas in the turbo expander 42 can flow into the second valve body 6, the gas can flow from the third outlet 62 to the outside, and / or, the gas can flow from the fourth outlet 63 to the third valve body 7 (fourth inlet 72); for the third valve body 7, the outside air can flow from the third inlet 71 to the air inlet 41a of the air compressor 41, and / or, the gas from the second valve body 6 can be received and flow to the air inlet 41a of the air compressor 41.

[0074] Thus, when the fourth outlet 63 of the second valve body 6 is connected to the fourth inlet 72 of the third valve body 7, the gas after the fuel cell reaction (the gas discharged from the air outlet 10b, the oxygen content in the air after the reaction is low) can enter the fuel cell again, which can reduce the oxygen content of the gas flowing into the air inlet 10a, that is, it can reduce the oxygen content in the purge gas during the shutdown purge stage, so as to complete the shutdown purge more quickly. Thus, after the fuel cell completes the purge process, the oxygen content on the cathode side is low, so that the electrochemical reaction in the fuel cell is reduced after shutdown (for example, the molar amount of fuel on the cathode side is reduced), so that the amount of electricity generated by the fuel cell is reduced, which is conducive to shortening the passive discharge time of the cathode side (for example, the high-voltage bus) after shutdown.

[0075] Optionally, the opening of the third valve body 7 is adjustable (for example, the opening of the third valve body 7 is adjusted by PID method), for example, the opening of the third inlet 71 and the fourth inlet 72 is adjustable, so that the opening of the third inlet 71 and the fourth inlet 72 can be controlled, so as to facilitate precise adjustment of the gas flow from the third inlet 71 and the fourth inlet 72 to the fifth outlet 73, that is, the ratio of the gas amount flowing from the third inlet 71 and the fourth inlet 72 to the fifth outlet 73 can be adjusted, so that the third valve body 7 can adjust the ratio of the reacted gas in the gas entering the air inlet 10a and the ambient air during the shutdown purge stage, for example, increase the amount of reacted gas in the gas entering the air inlet 10a, that is, reduce the oxygen content in the purge gas, thereby further accelerating the fuel cell to quickly complete the shutdown purge to achieve rapid shutdown.

[0076] In some embodiments, Figure 1As shown, the cathode system 100 also includes an intercooler 82, which is arranged on the intake pipe 9c, and the intercooler 82 is connected between the first outlet 52 and the humidification pipe 311, so that the intercooler 82 is located between the first valve body 5 and the humidifier 31, so that the intercooler 82 can adjust the temperature of the gas in the intake pipe 9c (for example, cooling to reduce the gas temperature), so that the gas entering the air inlet 10a is at a suitable temperature to ensure the normal operation of the fuel cell; and / or, the cathode system 100 also includes a second muffler 85, the second muffler 85 is arranged on the intake pipe 9c, and the second muffler 85 is connected between the exhaust port 41b and the first inlet 51, so that the second muffler 85 can effectively reduce the noise (for example, eddy current noise), vibration and roughness in the air compressor 41, thereby improving the noise or vibration of the fuel cell and improving comfort.

[0077] It can be seen that in the flow direction of the gas in the intake pipe 9c, the first valve body 5 is arranged upstream of the intercooler 82. For example, the first valve body 5 is arranged between the intercooler 82 and the air compressor 41. When the first inlet 51 of the first valve body 5 is connected to the first outlet 52 and the second outlet 53, the probability of surge of the air compressor 41 can be reduced, the power consumption of the air compressor 41 can be reduced, and the demand for heat exchange capacity (such as cooling capacity) of the intercooler 82 can be reduced.

[0078] For example, when the cathode system 100 is in a high-power operating state, the cathode side of the fuel cell has a higher demand for oxygen. At this time, the air compressor 41 is in a high-speed operating state. The high-speed flow of gas generated by the high speed of the air compressor 41 will produce larger vortex noise or jet noise in the intake pipe 9c. A second muffler 85 is provided at the exhaust port 41b and the first inlet 51, which can effectively reduce the noise in the intake pipe 9c.

[0079] Optionally, combined Figure 1 The cathode system 100 includes a second muffler 85 and a first muffler 86. The second muffler 85 is arranged on the air intake pipe 9c and is connected between the exhaust port 41b and the humidification pipe 311. The first muffler 86 is arranged at the mixing outlet 87a. Thus, the second muffler 85 can reduce the noise generated when the air compressor 41 is working, and the first muffler 86 can reduce the noise of the exhaust gas of the mixing device 87. Therefore, the second muffler 85 and the first muffler 86 work together to realize the two-stage muffler treatment of the cathode system 100, effectively reduce the noise, vibration and unevenness in the cathode system 100, and improve the sound quality of the fuel cell.

[0080] In some embodiments, the cathode system 100 includes a second valve body 6 and a third valve body 7, and the cathode system 100 also includes a filter 83 and a flow meter 84, the filter 83 is connected between the fifth outlet 73 and the air inlet 41a, for example, the filter 83 is arranged between the third valve body 7 and the air compressor 41, so that the filter 83 can filter the air flowing to the air inlet 41a, ensure the cleanliness of the air, and prevent the impurities in the air from affecting the air compressor 41, which is conducive to extending the service life of the air compressor 41. The flow meter 84 is connected between the filter 83 and the air inlet 41a, for example, the flow meter 84 is arranged between the filter 83 and the air compressor 41, so that the flow meter 84 calculates the amount of gas flowing to the air compressor 41.

[0081] Optionally, the cathode system 100 also includes a humidity sensor 88, which is used to detect the humidity of the gas flowing to the air inlet 10a. For example, the humidity sensor 88 is arranged between the humidifier 31 and the air inlet 10a. The humidity sensor 88 is communicated with the humidity adjustment component 3. The humidity adjustment component 3 can adjust the humidification intensity of the gas flowing to the air inlet 10a according to the humidity feedback from the humidity sensor 88 to ensure that the gas is at a suitable humidity.

[0082] Optionally, the cathode system 100 also includes a pressure sensor 89 and a temperature sensor 90, and the pressure sensor 89 and the temperature sensor 90 are provided at the air outlet 10b and the air inlet 10a, so that the pressure sensor 89 and the temperature sensor 90 can detect the air pressure and temperature of the gas flowing to the air inlet 10a and the air pressure and temperature of the gas flowing out of the air outlet 10b.

[0083] It can be understood that in the fuel cell, the oxygen provided must meet the pressure, flow, temperature, and humidity requirements of the cathode of the fuel cell stack, and different load power requirements and different environmental conditions have different requirements for the pressure, flow, temperature, and humidity of the oxygen on the cathode side. In the embodiment of the present application, a pressure sensor 89, a flow meter 84, a temperature sensor 90, and a humidity sensor 88 are set to meet the differentiated requirements of the fuel cell for oxygen parameters under different conditions.

[0084] Optionally, combined Figure 1 The cathode system 100 further includes a mixing device 87 , and the third outlet 62 of the second valve body 6 is connected to the gas inlet 87 b of the mixing device 87 , so that the gas flowing to the second valve body 6 can be discharged to the outside through the mixing device 87 .

[0085] In some embodiments, Figure 1As shown, the cathode system 100 includes a first switching valve 21, a second switching valve 22 and a third switching valve 23, and has at least one of a standby state, a first operating state, a second operating state and a purge state, so that the cathode system 100 has multiple operating states to adapt to the operation of the fuel cell. The cathode system 100 also includes a first valve body 5, a second valve body 6 and a third valve body 7.

[0086] In the standby state, the first inlet 51 is disconnected from the first outlet 52, the first inlet 51 is connected to the second outlet 53, the first switching valve 21 and the second switching valve 22 are both closed to enhance the sealing of the tail drain flow path, the third switching valve 23 is closed to enhance the sealing of the tail drain flow path, the second inlet 61 is connected to the third outlet 62, the second inlet 61 is disconnected from the fourth outlet 63, the third inlet 71 is connected to the fifth outlet 73, and the fourth inlet 72 is disconnected from the fifth outlet 73. In this way, when the air compressor 41 is working, the outside air enters the third valve body 7 and flows to the air compressor 41, the air discharged from the exhaust port 41b of the air compressor 41 flows to the first valve body 5 and flows to the air inlet end 42a of the turboexpander 42, and the air flowing out of the exhaust end 42b of the turboexpander 42 flows to the second valve body 6 and flows to the outside; thus, the air entering from the outside passes through the third valve body 7, the air compressor 41, the first valve body 5, the turboexpander 42 and the second valve body 6 in turn and flows from the second valve body 6 to the outside. At this time, the cathode system 100 is in standby state to ensure that the subsequent operating state works normally.

[0087] For example, combined with Figure 1The cathode system 100 further includes a fourth switching valve 24 and a fifth switching valve 25. The fourth switching valve 24 is disposed on the first branch 9a and between the drain outlet 13 and the water applicator 32. The fifth switching valve 25 is disposed between the humidifier 31 and the air inlet 10a. In the standby state, the fourth switching valve 24 and the fifth switching valve 25 are both closed to seal the cathode cavity in the stack and prevent electrochemical reactions from occurring in the stack. The cathode system 100 further includes a filter 83 and a flow meter 84. , humidity sensor 88, intercooler 82 and second muffler 85, the flow meter 84 is arranged between the filter 83 and the air compressor 41, and the filter 83 is connected to the fifth outlet 73 of the third valve body 7, the second muffler 85 is arranged between the air compressor 41 and the first inlet 51, the intercooler 82 is arranged between the first valve body 5 and the humidifier 31, and the intercooler 82 is connected to the first outlet 52 and the humidification pipeline 311, and the humidity sensor 88 is arranged between the fifth switching valve 25 and the air inlet 10a. In the standby state, the first inlet 51 is disconnected from the first outlet 52, and the first inlet 51 is connected to the second outlet 53; the first switching valve 21, the second switching valve 22 and the fifth switching valve 25 are all closed to ensure the sealing of the cathode side of the fuel cell and prevent electrochemical reactions from occurring on the cathode side; the second inlet 61 is connected to the third outlet 62, and the second inlet 61 is disconnected from the fourth outlet 63, the third inlet 71 is connected to the fifth outlet 73, and the fourth inlet 72 is disconnected from the fifth outlet 73, the air sucked in from the third valve body 7 flows to the air compressor 41, the second valve body 6 is disconnected from the third valve body 7, and the gas flowing from the turbo expander 42 to the second valve body 6 flows to the outside.

[0088] In the first operating state, the first outlet 52 and the second outlet 53 are connected to the first inlet 51 respectively, the first switching valve 21 and the second switching valve 22 are both opened, the second inlet 61 is connected to the third outlet 62, the second inlet 61 is disconnected from the fourth outlet 63, the third inlet 71 is connected to the fifth outlet 73, the fourth inlet 72 is disconnected from the fifth outlet 73, and the water applicator 32 is closed. In this way, when the air compressor 41 is working, the outside air enters the third valve body 7 and flows to the air compressor 41, and a part of the air discharged from the exhaust port 41b of the air compressor 41 flows from the first valve body 5 to the humidifier 31 and flows to the air inlet 10a, and the reacted gas is discharged from the air outlet 10b and passes through the first switching valve 21, the water separator 1 and the second switching valve 22 in sequence, and the gas flowing out of the second switching valve 22 flows to the air inlet end 42a of the turbo expander 42, and the air flowing out of the exhaust end 42b of the turbo expander 42 flows to the second valve body 6 and flows to the outside; another part of the air discharged from the exhaust port 41b of the air compressor 41 flows from the first valve body 5 to the air inlet end 42a of the turbo expander 42, and the air flowing out of the exhaust end 42b of the turbo expander 42 flows to the second valve body 6 and flows to the outside, thereby, the air inhaled from the outside passes through the third valve body 7, the air compressor 41 and the first valve body 5 in sequence, and the air is divided into two parts at the first valve body 5 and flows to the first outlet 52 and the second outlet 53 respectively, part of the air flowing to the first outlet 52 passes through the humidifier 31, the cathode side of the fuel cell, the first switching valve 21, the water separator 1 and the second switching valve 22, the turbo expander 42 and the second valve body 6 in sequence and flows from the second valve body 6 to the outside, and the other part of the air flowing to the second outlet 53 passes through the turbo expander 42 and the second valve body 6 in sequence and flows from the second valve body 6 to the outside. At this time, the cathode system 100 is in the first operating state, the air inhaled by the air compressor 41 does not all flow to the air inlet 10a, and the cathode system 100 is in a low-power output operating state.

[0089] For example, combined with Figure 1The cathode system 100 also includes a fourth switching valve 24, which is arranged on the first branch 9a and between the water distributor 1 and the water applicator 32. In the first operating state, the first outlet 52 and the second outlet 53 are respectively connected to the first inlet 51, and the first valve body 5 performs PID adjustment of the opening to adjust the ratio of the gas flowing from the first inlet 51 to the first outlet 52 and the second outlet 53 to ensure that the amount of gas flowing from the first outlet 52 to the air inlet 10a meets the needs of the fuel cell, and part of the gas will flow from the second outlet 53 to the air inlet end 42a of the turbo expander 42, which can prevent the air compressor 41 from surging, and the turbo expander 42 can use the first valve body 5 to divert the gas to do work, thereby reducing the power consumption of the air compressor 41. Among them, in the first operating state, the first switching valve 21 performs PID opening adjustment according to the pressure demand on the cathode side of the fuel cell to ensure that the proton exchange membrane has a suitable working efficiency; the second switching valve 22 is fully opened, so that the turbo expander 42 can use the gas discharged from the air outlet 10b to do work; the second inlet 61 is connected to the third outlet 62, the second inlet 61 is disconnected from the fourth outlet 63, the third inlet 71 is connected to the fifth outlet 73, the fourth inlet 72 is disconnected from the fifth outlet 73, the air sucked in from the third valve body 7 flows to the air compressor 41, the second valve body 6 is disconnected from the third valve body 7, and the gas flowing to the second valve body 6 flows to the outside. Of course, in the first operating state, the cathode system 100 is in the first working state, the humidifier 31 is working, and the water applicator 32 is not working, that is, the fourth switching valve 24 is closed to realize the closing of the water applicator 32, and the third switching valve 23 performs PID adjustment of the opening according to the liquid level height in the water separator 1 fed back by the liquid level detector 81, so that part of the water in the water separator 1 is discharged to the outside, so that the liquid level height in the water separator 1 is kept within a suitable range. The cathode system 100 also includes a fifth switching valve 25, which is arranged between the humidifier 31 and the air inlet 10a. In the first operating state, the fifth switching valve 25 is fully opened.

[0090] Of course, the way to close the water applicator 32 is not limited to this. Optionally, in other embodiments, in the first operating state, the cathode system 100 is in the first working state, the humidifier 31 is not working, and the water applicator 32 is working, that is, the fourth switching valve 24 is opened to allow the water applicator 32 to apply water to the moisture chamber 312.

[0091] In the second operating state, the first inlet 51 is connected to the first outlet 52, the first inlet 51 is disconnected from the second outlet 53, the first switching valve 21 and the second switching valve 22 are both opened, the second inlet 61 is connected to the third outlet 62, the second inlet 61 is disconnected from the fourth outlet 63, the third inlet 71 is connected to the fifth outlet 73, the fourth inlet 72 is disconnected from the fifth outlet 73, and the water applicator 32 is opened. In this way, when the air compressor 41 is working, the outside air enters the third valve body 7 and flows to the air compressor 41, the air discharged from the exhaust port 41b of the air compressor 41 flows from the first valve body 5 to the humidifier 31 and flows to the air inlet 10a, the reacted gas is discharged from the air outlet 10b and passes through the first switching valve 21, the water separator 1 and the second switching valve 22 in sequence, the gas flowing out of the second switching valve 22 flows to the air inlet end 42a of the turbo expander 42, and the air flowing out of the exhaust end 42b of the turbo expander 42 flows to the second valve body 6 and flows to the outside. Thus, the air inhaled from the outside passes through the third valve body 7, the air compressor 41, the first valve body 5, the humidifier 31, the cathode side of the fuel cell, the first switching valve 21, the water separator 1, the second switching valve 22, the turbo expander 42 and the second valve body 6 in sequence and flows from the second valve body 6 to the outside. At this time, the cathode system 100 is in the second operating state, and the air inhaled by the air compressor 41 all flows to the air inlet 10a, and the cathode system 100 is in a high-power or rated power output operating state.

[0092] For example, combined with Figure 1In the second operating state, the first inlet 51 is connected to the first outlet 52, and the first inlet 51 is disconnected from the second outlet 53, and all the air inhaled by the air compressor 41 flows to the cathode side of the fuel cell; the fifth switching valve 25 between the humidifier 31 and the air inlet 10a is fully opened; the first switching valve 21 performs PID opening adjustment according to the pressure requirement on the cathode side of the fuel cell to ensure that the proton exchange membrane has a suitable working efficiency; the second switching valve 22 is fully opened, so that the turbo expander 42 can use the gas discharged from the air outlet 10b to do work; the second inlet 61 is connected to the third outlet 62, and the second inlet 61 is disconnected from the fourth outlet 63, the third inlet 71 is connected to the fifth outlet 73, and the fourth inlet 72 is disconnected from the fifth outlet 73, the air inhaled from the third valve body 7 flows to the air compressor 41, the second valve body 6 is disconnected from the third valve body 7, and the gas flowing to the second valve body 6 flows to the outside. Of course, at this time, the third switching valve 23 performs PID adjustment of the opening according to the liquid level height in the water separator 1 fed back by the liquid level detector 81, so that part of the water in the water separator 1 is discharged to the outside, so that the liquid level in the water separator 1 is maintained within a suitable range so that all the tail gas flows into the turbo expander 42, thereby realizing the closed-loop control of the third switching valve 23; the cathode system 100 also includes a fourth switching valve 24, and the fourth switching valve 24 is used to switch the connection or disconnection between the drainage outlet 13 and the water applicator 32. In the second operating state, the cathode system 100 is in the second working state at this time, the humidifier 31 and the water applicator 32 work together, the fourth switching valve 24 is opened to realize the opening of the water applicator 32, and the fourth switching valve 24 can perform PID adjustment of the opening according to the humidity value fed back by the humidity sensor 88 to adjust the water intake of the water applicator 32, thereby meeting the air humidity demand of the cathode side of the fuel cell.

[0093] In the purge state, the first inlet 51 is connected to the first outlet 52, the first inlet 51 is disconnected from the second outlet 53, the first switching valve 21 and the second switching valve 22 are both opened, the second inlet 61 is disconnected from the third outlet 62, the second inlet 61 is connected to the fourth outlet 63, the third inlet 71 and the fourth inlet 72 are respectively connected to the fifth outlet 73, and the water applicator 32 is closed. In this way, all the reacted gases flow from the second valve body 6 to the third valve body 7, so that the reacted gases are mixed with the inhaled air and flow together to the air compressor 41, and the mixed gas flows to the air inlet 10a, that is, the mixed gas flows to the cathode side of the fuel cell. The oxygen content in the mixed gas is low, and the chemical reaction on the cathode side of the fuel cell gradually weakens, thereby accelerating the shutdown purge stage to reduce the shutdown purge time; at the same time, the reaction water generated in the stack can be quickly reduced. As a result, the air inhaled from the outside world flows back to the cathode side after reacting on the cathode side of the fuel cell in turn, which can accelerate the end of the shutdown purge stage.

[0094] It should be noted that when the chemical reaction on the cathode side of the fuel cell stops, that is, the generation of reaction water on the cathode side stops, the cathode system 100 stops purging and the purging state ends.

[0095] For example, combined with Figure 1 In the purge state, the first inlet 51 is connected to the first outlet 52, the first inlet 51 is disconnected from the second outlet 53, and all the air sucked in by the air compressor 41 flows to the cathode side of the fuel cell; the fifth switching valve 25 between the humidifier 31 and the air inlet 10a is fully opened; the first switching valve 21 performs PID opening adjustment according to the pressure requirement on the cathode side of the fuel cell to ensure that the proton exchange membrane has a suitable working efficiency; the second switching valve 22 is fully opened, so that the turbo expander 42 can use the gas discharged from the air outlet 10b to do work; the second inlet 61 is disconnected from the third outlet 62, and the second inlet 61 is connected to the fourth outlet 63, The third inlet 71 and the fourth inlet 72 are connected to the fifth outlet 73 respectively. The gas flowing to the second valve body 6 all flows to the third valve body 7, and is mixed with the gas sucked by the third valve body 7 to flow to the air compressor 41, that is, to the cathode side of the fuel cell. The third valve body 7 performs PID adjustment of the opening. For example, the opening of the third inlet 71 is adjusted by PID to ensure that the intake amount flowing to the air inlet 10a is sufficient, so that the intake amount flowing to the cathode side of the fuel cell has a lower oxygen content and a higher nitrogen content. The gas with a high nitrogen content can reduce the oxygen content in the cathode side of the fuel cell, reduce the generation of reaction water on the cathode side, and speed up the purge process. Secondly, after the purge is completed, the main residual gas on the cathode side of the fuel cell is nitrogen, which can prevent the electrochemical reaction from proceeding, and can reduce the passive discharge time of the high-voltage busbar, avoid the generation of negative pressure on the cathode side to a certain extent, and can reduce the negative pressure difference on the cathode side after shutdown and purge, which is beneficial to the sealing performance of the cathode side. Of course, the cathode system 100 also includes a fourth switching valve 24, which is used to switch the connection or disconnection between the drain outlet 13 and the water applicator 32. In the purge state, the fourth switching valve 24 is completely closed, and according to the calibrated water production in the purge stage, the liquid level detector 81 can feedback the liquid level height in the water separator 1, and the third switching valve 23 performs PID adjustment of the opening to drain the water in the water separator 1.

[0096] Thus, the cathode system 100 can switch between multiple states, or repeatedly switch between at least two states, etc., to adapt to the working requirements of the fuel cell. For example, the cathode system 100 sequentially passes through the standby state, the first operating state, the second operating state, the purge state, and the standby state, or the cathode system 100 sequentially passes through the standby state, the first operating state, the second operating state, the first operating state, the second operating state, the purge state, and the standby state, etc. Of course, the time of the cathode system 100 in the corresponding state is not limited.

[0097] It is understandable that a large amount of water will be generated on the cathode side of the fuel cell when the cathode system is in operation, and the generated water will be discharged through the air outlet. In the purge state, water will also be generated in the reactor, resulting in a longer purge time. The purge state in the embodiment of the present application is convenient for reducing the water generated by the reaction by quickly reducing the oxygen content in the fuel cell stack, thereby shortening the purge time, and at the same time making it convenient to achieve no water residue in the cathode side of the fuel cell after shutdown, so as to prevent the proton exchange membrane from being damaged at low temperatures.

[0098] The fuel cell according to the second embodiment of the utility model comprises the cathode system 100 according to the first embodiment of the utility model. For example, the fuel cell further comprises an anode system (for example, the anode system comprises a hydrogen supply device) and a thermal management system.

[0099] The fuel cell according to the embodiment of the present invention can improve the performance of the fuel cell by adopting the cathode system 100 described above.

[0100] In the description of the present invention, it should be understood that the terms "upper", "lower", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0101] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0102] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0103] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A cathode system for a cathode side of a fuel cell, wherein the cathode side of the fuel cell has an air inlet and an air outlet, characterized in that: The cathode system comprises: A water separator, the water separator is formed with a first inlet, an exhaust outlet and a drain outlet, and the water separator is used to separate gas from water in the gas discharged from the air outlet; A switching assembly, the switching assembly comprising a first switching valve and a fourth switching valve, the first switching valve being disposed between the air outlet and the first inlet and being used to switch the air outlet and the first inlet to be connected or disconnected; A humidity regulating component, the humidity regulating component includes a humidifier and a water applicator, the humidifier is formed with a humidification pipeline and a moisture cavity, the humidification pipeline is arranged in the moisture cavity and is suitable for connecting to the air inlet, the humidification pipeline is constructed as follows: water in the moisture cavity can penetrate into the humidification pipeline, the moisture cavity has a moisture inlet and a moisture outlet, the moisture inlet is suitable for selectively connecting to the air outlet, the moisture outlet is connected to the first inlet, the water applicator is connected to the drain outlet through a first branch, and is used to apply water to the moisture cavity, the fourth switching valve is arranged on the first branch, and the fourth switching valve is used to switch the connection or disconnection between the drain outlet and the water applicator.

2. The cathode system according to claim 1, characterized in that The switching assembly also includes a third switching valve and a liquid level detector. The third switching valve is connected to the drain outlet through a second branch and has an adjustable opening. The liquid level detector is used to detect the liquid level height in the water divider. The liquid level detector is communicatively connected to the third switching valve.

3. The cathode system according to claim 1, characterized in that Also included: a mixing device, the mixing device comprising a plurality of second inlets and a mixing outlet, the plurality of second inlets comprising a gas inlet and a liquid inlet, the gas inlet being connected to the exhaust outlet, the liquid inlet being connected to the drain outlet, and the mixing outlet being adapted to be connected to the outside to discharge the gas and liquid in the mixing device; The switching assembly further includes a third switching valve, which is connected between the drain outlet and the liquid inlet through a second branch and is used to switch the connection or disconnection between the drain outlet and the liquid inlet.

4. The cathode system according to claim 3, characterized in that Also includes: A first muffler is disposed at the mixing outlet.

5. The cathode system according to any one of claims 1 to 4, characterized in that: The switching assembly further includes a second switching valve, which is disposed downstream of the exhaust outlet and has an adjustable opening.

6. The cathode system according to claim 5, characterized in that The cathode system also includes: an air supply device, which includes an air compressor and a turbo expander that are interconnected, the air compressor is formed with an air inlet and an exhaust port, the air inlet is suitable for connecting to the outside world, the exhaust port is connected to the humidification pipeline through an air inlet pipeline, the turbo expander has an air inlet end and an exhaust end, the air inlet end is connected to the second switching valve through a first exhaust pipeline, and the exhaust end is suitable for connecting to the outside world.

7. The cathode system according to claim 6, characterized in that Also includes: a first valve body, the first valve body being arranged on the intake pipeline and forming a first inlet, a first outlet and a second outlet, each of the first outlet and the second outlet being selectively connected to the first inlet, the first inlet being connected to the exhaust port, the first outlet being connected to the humidification pipeline, and the second outlet being connected to the intake end through a second exhaust pipeline; and / or A second valve body and a third valve body, the second valve body is formed with a second inlet, a third outlet and a fourth outlet, the second inlet is connected to the exhaust end, the third outlet is suitable for connecting with the outside, the third valve body includes a third inlet, a fourth inlet and a fifth outlet, the third inlet is suitable for connecting with the outside, the fourth inlet is connected to the fourth outlet, and the fifth outlet is connected to the intake port.

8. The cathode system according to claim 7, characterized in that The cathode system includes a first switching valve, a second switching valve and a third switching valve, and has at least one state of a standby state, a first operating state, a second operating state and a purge state. In the standby state, the first inlet is disconnected from the first outlet, the first inlet is connected to the second outlet, the first switching valve, the second switching valve and the third switching valve are all closed, the second inlet is connected to the third outlet, the second inlet is disconnected from the fourth outlet, the third inlet is connected to the fifth outlet, and the fourth inlet is disconnected from the fifth outlet; In a first operating state, the first outlet and the second outlet are respectively connected to the first inlet, the first switching valve and the second switching valve are both opened, the second inlet is connected to the third outlet, the second inlet is disconnected from the fourth outlet, the third inlet is connected to the fifth outlet, the fourth inlet is disconnected from the fifth outlet, and the water applicator is closed; In a second operating state, the first inlet is connected to the first outlet, the first inlet is disconnected from the second outlet, the first switching valve and the second switching valve are both opened, the second inlet is connected to the third outlet, the second inlet is disconnected from the fourth outlet, the third inlet is connected to the fifth outlet, the fourth inlet is disconnected from the fifth outlet, and the water applicator is opened; In the purge state, the first inlet is connected to the first outlet, the first inlet is disconnected from the second outlet, the first switching valve and the second switching valve are both opened, the second inlet is disconnected from the third outlet, the second inlet is connected to the fourth outlet, the third inlet and the fourth inlet are respectively connected to the fifth outlet, and the water applicator is closed.

9. The cathode system according to claim 7, characterized in that The cathode system includes a second valve body and a third valve body, and further includes a filter and a flow meter. The filter is connected between the fifth outlet and the air inlet, and the flow meter is connected between the filter and the air inlet.

10. A fuel cell, characterized in that: Comprising a cathode system according to any one of claims 1-9.

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