Fuel cell cathode gas path system and fuel cell

Abstract

A fuel cell cathode gas path system and a fuel cell. The fuel cell cathode gas path system comprises a compressor (11), a flow control valve (12), a charge air cooler (13), a humidifier (14), a fuel cell stack cathode gas channel (15), a heat exchanger (16), a liquid-water separator (17) and an expander (18). The flow control valve (12) can be switched between a first valve position and a second valve position; when the flow control valve (12) is in the first valve position, the compressor (11), a first air outlet (121) of the flow control valve (12), the charge air cooler (13), the humidifier (14) and the fuel cell stack cathode gas channel (15) are successively communicated to form a first flow path; when the flow control valve (12) is in the second valve position, the compressor (11), a second air outlet (122) of the flow control valve (12), the heat exchanger (16), the humidifier (14) and the fuel cell stack cathode gas channel (15) are successively communicated to form a second flow path; the flow control valve (12) may also be in a valve position state between the first valve position and the second valve position. The gas path system increases recovered energy of the expander (18) and can effectively remove droplets entering the expander (18).

Description

Fuel cell cathode gas path system and fuel cell TECHNICAL FIELD

[0001] The present application relates to the technical field of fuel cells, and particularly relates to a fuel cell cathode gas path system and a fuel cell. BACKGROUND

[0002] The cathode gas path system of the fuel cell comprises a compressor for compressing air to the pressure level required by the fuel cell stack, usually 2 bar or higher. As the load of the fuel cell stack changes, the outlet pressure of the fuel cell stack can also reach or exceed 2 bar. The high-pressure gas generated after the electrochemical reaction of the fuel cell stack still has a large energy recovery potential, especially through an expander.

[0003] The expander is in driving connection with the compressor, and the high-pressure gas formed after the reaction of the fuel cell stack can drive the compressor through the expander to realize energy recovery. However, the expander is easily impacted by liquid water droplets. Therefore, it is necessary to remove as many liquid droplets as possible to prevent damage to the expander. How to effectively remove the liquid droplets entering the expander becomes an important technical problem to be solved by those skilled in the art.

[0004] SUMMARY

[0005] The purpose of the present application is to provide a fuel cell cathode gas path system and a fuel cell which can effectively remove liquid droplets entering the expander.

[0006] In a first aspect, the present application provides a fuel cell cathode gas path system, comprising a compressor, a flow control valve, a pressurized air cooler, a humidifier, a fuel cell stack cathode gas passage, a heat exchanger, a liquid water separator and an expander; wherein,

[0007] The flow control valve comprises an air inlet, a first air outlet and a second air outlet, the air outlet of the compressor is in communication with the air inlet, the flow control valve is adapted to switch between a first valve position and a second valve position, in the first valve position state, the air inlet is in communication with the first air outlet, and the air inlet is cut off between the second air outlet, in the second valve position state, the air inlet is in communication with the second air outlet, and the air inlet is cut off between the first air outlet, and when the flow control valve is in any valve position between the first valve position and the second valve position, the first air outlet and the second air outlet are both in communication with the air inlet, and the opening degrees of the two communication paths are inversely proportional;

[0008] The air inlet of the pressurized air cooler is in communication with the first air outlet;

[0009] The humidifier comprises a first humidification passage, the air outlet of the pressurized air cooler is in communication with the air inlet of the first humidification passage, and the air outlet of the first humidification passage is in communication with the air inlet of the fuel cell stack cathode gas passage.

[0010] The heat exchanger comprises a first heat exchange channel and a second heat exchange channel, the first heat exchange channel and the second heat exchange channel are adapted to exchange heat, the gas inlet of the first heat exchange channel is communicated with the second gas outlet of the flow control valve, the gas outlet of the first heat exchange channel is communicated with the gas inlet of the first humidification channel, and the gas inlet of the second heat exchange channel is communicated with the gas outlet of the fuel cell stack cathode gas channel;

[0011] The gas inlet of the liquid water separator is communicated with the gas outlet of the second heat exchange channel, and the gas outlet of the liquid water separator is communicated with the gas inlet of the expander;

[0012] The expander is drivingly connected with the compressor.

[0013] The fuel cell cathode gas circuit system provided by the application further comprises a first bypass valve, the gas inlet of the first bypass valve is communicated with the gas outlet of the compressor, and the gas outlet of the first bypass valve is communicated with the gas inlet of the expander.

[0014] The humidifier further comprises a second humidification channel, the second humidification channel is adapted to supply water to the first humidification channel, the gas outlet of the fuel cell stack cathode gas channel is communicated with the gas inlet of the second humidification channel, and the gas outlet of the second humidification channel is communicated with the gas inlet of the second heat exchange channel.

[0015] The fuel cell cathode gas circuit system provided by the application further comprises a first air cut-off valve arranged between the gas outlet of the booster air cooler and the gas inlet of the first humidification channel.

[0016] The second air cut-off valve is arranged between the gas outlet of the second humidification channel and the gas inlet of the second heat exchange channel, and the first air cut-off valve and the second air cut-off valve are controlled by the same actuator.

[0017] The fuel cell cathode gas circuit system provided by the application further comprises a bypass pipeline arranged between the gas inlet and the gas outlet of the first humidification channel, and a second bypass valve arranged on the bypass pipeline.

[0018] The fuel cell cathode gas circuit system provided by the application further comprises a coolant channel and a coolant pump, the coolant channel is internally provided with a coolant, the coolant is used for cooling the gas flowing through the booster air cooler, and the coolant pump is adapted to drive the coolant to flow in the coolant channel.

[0019] The fuel cell cathode gas circuit system provided by the application further comprises a controller, the controller is adapted to control the fuel cell cathode gas circuit system to operate in a first mode, in the first mode, the first bypass valve is in an open state, the flow control valve is in a first valve position state, and the coolant pump is in a closed state.

[0020] and / or the controller is adapted to control the fuel cell cathode gas path system to operate in a second mode in which the first bypass valve is in a closed state, the flow control valve is in a first valve position state, and the coolant pump is in a closed state or drives the coolant at a first preset flow rate or less;

[0021] and / or the controller is adapted to control the fuel cell cathode gas path system to operate in a third mode in which the first bypass valve is in a closed state, the flow control valve is in a first valve position state, and the coolant pump drives the coolant at a second preset flow rate or more, the second preset flow rate being greater than the first preset flow rate;

[0022] and / or the controller is adapted to control the fuel cell cathode gas path system to operate in a fourth mode in which the first bypass valve is in a closed state, the flow control valve is in a state between the first valve position and a second valve position, and the coolant pump drives the coolant at a second preset flow rate or more, the second preset flow rate being greater than the first preset flow rate;

[0023] and / or the controller is adapted to control the fuel cell cathode gas path system to operate in a fifth mode in which the first bypass valve is in a closed state, the flow control valve is in a second valve position state, and the charge air cooler does not cool the cathode gas.

[0024] According to the fuel cell cathode gas path system provided by the present application, the flow control valve comprises a first butterfly valve plate and a second butterfly valve plate, the first butterfly valve plate is adapted to control the conduction or block of the first gas outlet and the gas inlet, and the second butterfly valve plate is adapted to control the conduction or block of the second gas outlet and the gas inlet; the first butterfly valve plate and the second butterfly valve plate are driven to rotate by the same rotary brake.

[0025] In a second aspect, the present application provides a fuel cell comprising the fuel cell cathode gas path system according to any one of the above.

[0026] The technical scheme provided by the application comprises a compressor, a flow control valve, a pressurized air cooler, a humidifier, a fuel cell stack cathode gas passage, a heat exchanger, a liquid water separator and an expander. The flow control valve can be switched between a first valve position and a second valve position. When the flow control valve is in the first valve position, the compressor, the first air outlet of the flow control valve, the pressurized air cooler, the humidifier and the fuel cell stack cathode gas passage are sequentially connected to form a first flow path, and air flows into the fuel cell stack cathode gas passage through the first flow path to participate in the reaction. When the flow control valve is in the second valve position, the compressor, the second air outlet of the flow control valve, the heat exchanger, the humidifier and the fuel cell stack cathode gas passage are sequentially connected to form a second flow path, and air flows into the fuel cell stack cathode gas passage through the second flow path to participate in the reaction. The flow control valve can also be in a valve position between the first valve position and the second valve position. In this valve position, the first flow path and the second flow path are simultaneously connected, and air enters the fuel cell stack cathode gas passage through the first flow path and the second flow path. That is, the pressurized gas discharged by the compressor enters the humidifier after passing through the pressurized air cooler and the heat exchanger, and then enters the fuel cell stack cathode gas passage. The gas discharged from the fuel cell stack cathode gas passage passes through the heat exchanger and the liquid water separator to enter the expander. When the flow control valve is in the second valve position or the valve position between the first valve position and the second valve position, the gas discharged from the fuel cell stack cathode gas passage can exchange heat with the gas in the second flow path in the heat exchanger. In this way, the gas discharged from the fuel cell stack cathode gas passage is input into the expander, and the expander can drive the compressor, thereby fully utilizing the pressure energy of the gas discharged from the fuel cell stack cathode gas passage. Moreover, in some working conditions, the heat energy discharged by the compressor can exchange heat with the gas discharged from the fuel cell stack cathode gas passage, thereby increasing the temperature of the gas flow before entering the expander and reducing liquid water droplets. Moreover, in some working conditions, the excess heat of the gas discharged by the compressor can be recovered, and the heat exchanger can exchange heat from the gas before entering the expander, instead of completely discharging the heat through the pressurized air cooler, thereby reducing the power consumption of the compressor-expander system and improving the efficiency of the entire system.

[0027] In a further scheme, the fuel cell cathode gas passage system further comprises a first bypass valve, the air inlet of the first bypass valve is connected with the air outlet of the compressor, and the air outlet of the first bypass valve is connected with the air inlet of the expander. In some working conditions, the first bypass valve can be opened. When the first bypass valve is opened, the air discharged by the compressor can partially enter the expander through the first bypass valve, thereby increasing the temperature of the gas in the expander and driving the compressor by the expander. For example, when the minimum operating speed of the compressor can transport excessive air flow, the first bypass valve can be started to reduce the air flow flowing to the fuel cell stack cathode gas passage. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a schematic diagram of a fuel cell cathode gas path system according to an embodiment of the present application.

[0029] Figure 2 is a schematic diagram of flow control valve control logic according to an embodiment of the present application.

[0030] Figure 3 is a schematic diagram of a fuel cell cathode gas path system in a first mode of operation according to an embodiment of the present application.

[0031] Figure 4 is a schematic diagram of a fuel cell cathode gas path system in a second mode of operation according to an embodiment of the present application.

[0032] Figure 5 is a schematic diagram of a fuel cell cathode gas path system in a third mode of operation according to an embodiment of the present application.

[0033] Figure 6 is a schematic diagram of a fuel cell cathode gas path system in a fourth mode of operation according to an embodiment of the present application.

[0034] Figure 7 is a schematic diagram of a fuel cell cathode gas path system in a fifth mode of operation according to an embodiment of the present application. DETAILED DESCRIPTION

[0035] Specific embodiments according to the present application will be described hereinafter with reference to the accompanying drawings. The following detailed description and drawings are merely included to illustrate the principles of the present application, and the scope of the present application is not limited to the preferred embodiments described herein. The scope of the present application is defined by the claims.

[0036] It should be noted that the orientation or positional relationship referred to in the present specification is based on the orientation or positional relationship described in the drawings, and is only for the convenience and simplification of description, and does not indicate or imply that the device referred to must have a specific orientation or be constructed in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0037] As shown in Figure 1, the fuel cell cathode gas path system provided by the embodiment of the present application includes a compressor 11, a flow control valve 12, a pressurized air cooler 13, a humidifier 14, a fuel cell stack cathode gas passage 15, a heat exchanger 16, a liquid water separator 17, and an expander 18.

[0038] As shown in FIG. 1 and FIG. 2, the flow control valve 12 includes an inlet, a first outlet 121 and a second outlet 122, wherein the A port of the flow control valve 12 is the first outlet 121 and the B port is the second outlet 122. The outlet of the compressor 11 is connected to the inlet of the flow control valve 12, and the flow control valve 12 is adapted to switch between a first valve position and a second valve position, in the first valve position, the inlet is connected to the first outlet 121 and the inlet is cut off from the second outlet 122, in the second valve position, the inlet is connected to the second outlet 122 and the inlet is cut off from the first outlet 121, when the flow control valve 12 is in any valve position between the first valve position and the second valve position, the first outlet 121 and the second outlet 122 are both connected to the inlet, and the opening degrees of the two connection paths are inversely proportional. The inlet of the intercooler 13 is connected to the first outlet 121, and the intercooler 13 contains a coolant inside, the heat of the air can be exchanged to the coolant, and then the coolant can dissipate the heat to the environment or be used to heat the air flow in the vehicle cabin.

[0039] The humidifier 14 includes a first humidification passage 141, the outlet of the intercooler 13 is connected to the inlet of the first humidification passage 141, and the outlet of the first humidification passage 141 is connected to the inlet of the fuel cell stack cathode gas passage 15. Before entering the fuel cell stack, the air needs to be humidified by the humidifier 14 to heat the air to a predetermined humidity.

[0040] The heat exchanger 16 includes a first heat exchange passage and a second heat exchange passage 161, the first heat exchange passage and the second heat exchange passage 161 are adapted to exchange heat, the inlet of the first heat exchange passage is connected to the second outlet 122 of the flow control valve 12, the outlet of the first heat exchange passage is connected to the inlet of the first humidification passage 141, and the inlet of the second heat exchange passage 161 is connected to the outlet of the fuel cell stack cathode gas passage 15. The inlet of the liquid water separator 17 is connected to the outlet of the second heat exchange passage 161, and the outlet of the liquid water separator 17 is connected to the inlet of the expander 18.

[0041] The expander 18 is drivingly connected to the compressor 11. In some embodiments, the compressor 11 is an electric compressor 11, and the expander 18 can be drivingly connected to the motor of the electric compressor 11 to provide power for the motor.

[0042] The flow control valve 12 can switch between a first valve position and a second valve position. When the flow control valve 12 is in the first valve position, the compressor 11, the first gas outlet 121 of the flow control valve 12, the intercooler 13, the humidifier 14, and the fuel cell stack cathode gas passage 15 are sequentially connected to form a first flow path, and air flows into the fuel cell stack cathode gas passage 15 through the first flow path to participate in the reaction. When the flow control valve 12 is in the second valve position, the compressor 11, the second gas outlet 122 of the flow control valve 12, the heat exchanger 16, the humidifier 14, and the fuel cell stack cathode gas passage 15 are sequentially connected to form a second flow path, and air flows into the fuel cell stack cathode gas passage 15 through the second flow path to participate in the reaction. The flow control valve 12 can also be in a valve position between the first valve position and the second valve position. In this valve position, the first flow path and the second flow path are simultaneously connected, and air enters the fuel cell stack cathode gas passage 15 through the first flow path and the second flow path. That is, the compressed gas discharged from the compressor 11 enters the humidifier 14 after passing through the intercooler 13 and the heat exchanger 16, and then enters the fuel cell stack cathode gas passage 15. The gas discharged from the fuel cell stack cathode gas passage 15 passes through the heat exchanger 16 and the liquid water separator 17 and enters the expander 18. When the flow control valve 12 is in the second valve position or the valve position between the first valve position and the second valve position, the gas discharged from the fuel cell stack cathode gas passage 15 can exchange heat with the gas in the second flow path in the heat exchanger 16. In this way, after the gas discharged from the fuel cell stack cathode gas passage 15 enters the expander 18, the expander 18 can drive the compressor 11, thereby fully utilizing the pressure energy of the gas discharged from the fuel cell stack cathode gas passage 15. Moreover, under some working conditions, the heat energy of the gas discharged from the compressor 11 can exchange heat with the gas discharged from the fuel cell stack cathode gas passage 15, thereby increasing the temperature of the gas before it enters the expander 18 and reducing the amount of liquid water droplets. Furthermore, under some working conditions, the excess heat of the gas discharged from the compressor 11 can be recovered and exchanged to the gas before it enters the expander 18 through the heat exchanger 16, instead of being completely discharged through the intercooler 13, thereby reducing the power consumption of the compressor 11-expander 18 system and improving the efficiency of the entire system.

[0043] In a further aspect, the fuel cell cathode gas passage system further comprises a first bypass valve 19, the inlet of the first bypass valve 19 being connected to the outlet of the compressor 11, and the outlet of the first bypass valve 19 being connected to the inlet of the expander 18.

[0044] In some operating conditions, the first bypass valve 19 can be opened, when the first bypass valve 19 is opened, the air discharged from the compressor 11 can partially pass through the first bypass valve 19 into the expander 18, to increase the temperature of the air in the expander 18, and to drive the compressor 11 by the expander 18. For example, when the minimum operating speed of the compressor 11 can deliver excessive air flow, the first bypass valve 19 can be started to reduce the air flow to the cathode gas channel 15 of the fuel cell stack.

[0045] In a further embodiment, the humidifier 14 further comprises a second humidification channel 142, the second humidification channel 142 is adapted to supply moisture to the first humidification channel 141, the outlet of the cathode gas channel 15 of the fuel cell stack is communicated with the inlet of the second humidification channel 142, and the outlet of the second humidification channel 142 is communicated with the inlet of the second heat exchange channel 161.

[0046] The reacted gas discharged from the cathode gas channel 15 of the fuel cell stack has high humidity, and the part of the gas is introduced into the humidifier 14, which can provide water source for the air to be input into the cathode gas channel 15 of the fuel cell stack, and at the same time reduce the humidity of the discharged gas, after further heating and water removal by the heat exchanger 16 and the liquid water separator 17, the gas enters the expander 18, to avoid the adverse effects of liquid water on the expander 18.

[0047] In a further embodiment, a first air cut-off valve 201 is arranged between the outlet of the air cooler 13 and the inlet of the first humidification channel 141 of the humidifier 14. In some operating conditions, the passage between the air cooler 13 and the humidifier 14 can be cut off by closing the first air cut-off valve 201.

[0048] Further, a second air cut-off valve 202 is arranged between the outlet of the second humidification channel 142 of the humidifier 14 and the inlet of the second heat exchange channel 161, and the first air cut-off valve 201 and the second air cut-off valve 202 are controlled by the same actuator. Specifically, the first air cut-off valve 201 and the second air cut-off valve 202 can be synchronously driven to open or close by the same motor.

[0049] In a further embodiment, a bypass pipeline 143 is arranged between the inlet and the outlet of the first humidification channel 141 of the humidifier 14, and a second bypass valve 144 is arranged on the bypass pipeline 143. In some operating conditions, the air entering the fuel cell stack can not pass through the humidification of the humidifier 14, at this time, the second bypass valve 144 can be opened, and the air is directly input into the cathode gas channel 15 of the fuel cell stack through the bypass pipeline 143, without the humidification of the first humidification channel 141.

[0050] In a further embodiment, the charge air cooler 13 is provided with a coolant channel and a coolant pump, the coolant channel is internally provided with a coolant for cooling the gas flowing through the charge air cooler 13, and the coolant pump is adapted to drive the coolant to flow in the coolant channel. When the coolant pump is started, the coolant is driven to flow in the coolant channel of the charge air cooler 13, and the effect of cooling the air is achieved. When the coolant pump is stopped, the coolant stops flowing in the coolant channel and no longer plays the role of cooling the air.

[0051] In some embodiments, the fuel cell cathode gas circuit system further comprises a controller adapted to control the fuel cell cathode gas circuit system to operate in a first mode, and / or a second mode, and / or a third mode, and / or a fourth mode, and / or a fifth mode.

[0052] In the first mode, as shown in Fig. 3, the first bypass valve 19 is in an open state, the flow control valve 12 is in a first valve position state, and the coolant pump is in a closed state.

[0053] Specifically, when the minimum operating speed of the compressor 11 will deliver excessive air flow, the controller controls the first bypass valve 19 to be started to reduce the air flow to the fuel cell stack. Generally, under the cold start condition below -10°C, the battery voltage will be reduced to below 0.3V, so as to generate more heat energy than electricity in the fuel cell stack. This rapid cold start stage can quickly heat the fuel cell stack, for example, from below -30°C to 5°C in less than one minute. In order to control the chemical energy consumption in a very short time and prevent excessive water from freezing, the air flow can be limited, and therefore the first bypass valve 19 can be opened. At the same time, the first air outlet 121 of the flow control valve 12 is fully opened, the second air outlet 122 is fully closed, and the coolant pump of the charge air cooler 13 is closed, so that the hot air generated by the compressor 11 helps to preheat the fuel cell stack.

[0054] In the second mode, as shown in Fig. 4, the first bypass valve 19 is in a closed state, the flow control valve 12 is in a first valve position state, and the coolant pump is in a closed state or drives the coolant at a flow rate lower than or equal to a first preset flow rate.

[0055] The second mode can be a pre-heat mode after the freeze start described in the first mode. For example, the fuel cell stack is running with high thermal efficiency and very low load, it can run in the second mode, in which the first bypass valve 19 is closed, while the flow control valve 12 still has its first gas outlet 121 open and the second gas outlet 122 closed. If the outlet temperature T1 of the compressor 11 does not exceed 70℃, cooling by the coolant of the charge air cooler 13 can not be required, and can be directly input to the humidifier 14 and extract moisture from the outlet of the fuel cell cathode gas passage. In this mode, the coolant of the charge air cooler 13 can be stopped or run at a small flow rate, i.e. the coolant pump is in a closed state or drives the coolant at a flow rate lower than or equal to the first preset flow rate.

[0056] In the third mode, as shown in FIG. 5, the first bypass valve 19 is in a closed state, the flow control valve 12 is in a first valve position state, and the coolant pump drives the coolant at a flow rate higher than or equal to a second preset flow rate, which is greater than the first preset flow rate.

[0057] The third mode is a stage in which the coolant path of the charge air cooler 13 is fully open to transfer the heat of the air compressor 11 to the coolant, which can be used to heat the cabin or other auxiliary components, or temporarily shut down the fuel cell power supply and restart the system to a low component load (i.e. start-stop scenario) when the fuel cell stack temperature does not decrease significantly. If the water produced by the fuel cell stack does not exceed the humidity level that causes water droplets to enter the expander 18, the second gas outlet 122 of the flow control valve 12 is still closed and the first gas outlet 121 is fully open, i.e. in the first valve position. In this mode, the coolant path of the charge air cooler 13 is open to transfer the heat of the compressor 11 to the coolant.

[0058] In the fourth mode, as shown in FIG. 6, the first bypass valve 19 is in a closed state, the flow control valve 12 is in a state between the first valve position and the second valve position, and the coolant pump drives the coolant at a flow rate higher than or equal to the second preset flow rate, which is greater than the first preset flow rate.

[0059] The fourth mode can be when the temperature T1 of the outlet of the compressor 11 is much higher than the normal operating temperature of the fuel cell stack, and intermediate cooling is required to prevent the humidifier 14 or the cathode side of the fuel cell stack from overheating. If both the fuel cell stack and the compressor 11 are operating at very high loads, for example, the temperature T1 of the outlet of the compressor 11 is much greater than 100°C, then intermediate cooling by the charge air cooler 13 is necessary to reduce the temperature of the air before it enters the humidifier 14. At the same time, the fuel cell stack will produce a large amount of moisture, which can result in a large amount of liquid condensation after the outlet, and there is a possibility that liquid water droplets will remain after passing through the liquid water separator 17. Therefore, it is meaningful to recover part of the heat energy of the compressor 11 at the heat exchanger 16 to increase the temperature of the gas to reduce the liquid water droplets. In addition, this energy recovery improves the overall efficiency of the compressor 11-expander 18, and helps to improve the efficiency of the entire fuel cell system. In this mode, both the first outlet 121 and the second outlet 122 of the flow control valve 12 are open, and are controlled in a certain proportion.

[0060] In the fifth mode, as shown in FIG. 7, the first bypass valve 19 is in a closed state, the flow control valve 12 is in a second valve position state, and the charge air cooler does not cool the cathode gas.

[0061] In the case of the fifth mode, only the energy recovery of the heat exchanger 16 is sufficient to adjust the temperature of the air discharged by the compressor 11, so that intermediate cooling by the charge air cooler 13 is not required. When the temperature T1 of the outlet of the compressor 11 > the temperature T2 of the inlet of the second heat exchange channel 161 of the heat exchanger 16, but T1 is only slightly higher than the optimal temperature of the cathode gas inlet before the humidifier 14, and the total temperature difference between T1 and T0 is less than 5°C. At the same time, the cooling of the fuel cell stack can also achieve the necessary cooling of the cathode gas. In this mode, the first outlet 121 of the flow control valve 12 is completely closed and the second outlet 122 is completely open.

[0062] In some embodiments, the flow control valve 12 includes a first butterfly valve plate and a second butterfly valve plate, the first butterfly valve plate being adapted to control the conduction or cutoff of the first outlet 121 to the inlet, i.e., the conduction or cutoff of the first outlet 121 to the inlet can be achieved by controlling the rotation of the first butterfly valve plate. The second butterfly valve plate is adapted to control the conduction or cutoff of the second outlet 122 to the inlet. The first butterfly valve plate and the second butterfly valve plate are driven to rotate by the same rotary brake, for example, the two butterfly valve plates can be driven to rotate synchronously by the same motor. In this way, the flow control valve 12 has a simple structure, low cost, and is easy to control.

[0063] In another aspect, the embodiments of the present application also provide a fuel cell, which comprises the fuel cell cathode gas path system according to any one of the above embodiments. The fuel cell provided by the embodiments can effectively remove the liquid droplets entering the expander 18. The derivation process of the beneficial effects of the fuel cell provided by the embodiments is similar to the derivation process of the beneficial effects of the fuel cell cathode gas path system described above, and thus will not be described here again.

[0064] Although the exemplary embodiments of the present application have been described with reference to the drawings in the foregoing description, the present application is not limited to the above-described specific embodiments, and the scope of protection of the present application should be defined by the claims and their equivalents.

[0065] List of reference numerals 11, compressor; 12, flow control valve; 121, first gas outlet; 122, second gas outlet; 13, supercharged air cooler; 14, humidifier; 141, first humidification passage; 142, second humidification passage; 143, bypass pipeline; 144, second bypass valve; 15, fuel cell stack cathode gas passage; 16, heat exchanger; 161, second heat exchange passage; 17, liquid water separator; 18, expander; 19, first bypass valve; 201, first air shut-off valve; 202, second air shut-off valve.

Claims

1. A fuel cell cathode gas circuit system, comprising a compressor (11), a flow control valve (12), a charge air cooler (13), a humidifier (14), a fuel cell stack cathode gas passage (15), a heat exchanger (16), a liquid water separator (17) and an expander (18), wherein, the flow control valve (12) comprises an inlet, a first outlet (121) and a second outlet (122), the outlet of the compressor (11) is communicated with the inlet, the flow control valve (12) is adapted to switch between a first valve position and a second valve position, in the first valve position, the inlet is communicated with the first outlet (121) and cut off between the inlet and the second outlet (122), in the second valve position, the inlet is communicated with the second outlet (122) and cut off between the inlet and the first outlet (121), and when the flow control valve (12) is in any valve position between the first valve position and the second valve position, the first outlet (121) and the second outlet (122) are both communicated with the inlet, and the opening degrees of the two communication paths are inversely proportional; the inlet of the charge air cooler (13) is communicated with the first outlet (121) ; the humidifier (14) comprises a first humidification passage (141), the outlet of the charge air cooler (13) is communicated with the inlet of the first humidification passage (141), and the outlet of the first humidification passage (141) is communicated with the inlet of the fuel cell stack cathode gas passage (15) ; the heat exchanger (16) comprises a first heat exchange passage and a second heat exchange passage (161), the first heat exchange passage and the second heat exchange passage (161) are adapted to exchange heat, the inlet of the first heat exchange passage is communicated with the second outlet (122) of the flow control valve (12), the outlet of the first heat exchange passage is communicated with the inlet of the first humidification passage (141), and the inlet of the second heat exchange passage (161) is communicated with the outlet of the fuel cell stack cathode gas passage (15) ; the inlet of the liquid water separator (17) is communicated with the outlet of the second heat exchange passage (161), the outlet of the liquid water separator (17) is communicated with the inlet of the expander (18), the expander (18) is drivingly connected with the compressor (11). 2.The fuel cell cathode gas circuit system according to claim 1, further comprising a first bypass valve (19), the inlet of the first bypass valve (19) is communicated with the outlet of the compressor (11), and the outlet of the first bypass valve (19) is communicated with the inlet of the expander (18). ​ 3. The fuel cell cathode gas path system according to claim 1, wherein, The humidifier (14) further comprises a second humidification passage (142) adapted to supply moisture to the first humidification passage (141), an outlet of the fuel cell stack cathode gas passage (15) is in communication with an inlet of the second humidification passage (142), and an outlet of the second humidification passage (142) is in communication with an inlet of the second heat exchange passage (161).

4. The fuel cell cathode gas path system according to claim 3, wherein An outlet of the charge air cooler (13) is in communication with an inlet of the first humidification passage (141), and a first air cut-off valve (201) is arranged between the outlet of the charge air cooler (13) and the inlet of the first humidification passage (141).

5. The fuel cell cathode gas gas path system according to claim 4, wherein, An outlet of the second humidification passage (142) is in communication with an inlet of the second heat exchange passage (161), and a second air cut-off valve (202) is arranged between the outlet of the second humidification passage (142) and the inlet of the second heat exchange passage (161), and the first air cut-off valve (201) and the second air cut-off valve (202) are controlled by the same actuator.

6. The fuel cell cathode gas path system according to claim 1, wherein A bypass pipeline (143) is arranged between an inlet and an outlet of the first humidification passage (141), and a second bypass valve (144) is arranged on the bypass pipeline (143).

7. The fuel cell cathode gas path system according to claim 2, wherein The charge air cooler (13) is provided with a coolant passage and a coolant pump, the coolant passage is internally provided with a coolant, the coolant is used to cool the gas flowing through the charge air cooler (13), and the coolant pump is adapted to drive the coolant to flow in the coolant passage.

8. The fuel cell cathode gas path system according to claim 7, further comprising a controller adapted to control the fuel cell cathode gas path system to operate in a first mode, in which the first bypass valve (19) is in an open state, the flow control valve (12) is in a first valve position state, and the coolant pump is in a closed state; and / or, the controller is adapted to control the fuel cell cathode gas path system to operate in a second mode, in which the first bypass valve (19) is in a closed state, the flow control valve (12) is in a first valve position state, and the coolant pump is in a closed state or drives the coolant at a flow rate lower than or equal to a first preset flow rate; and / or, the controller is adapted to control the fuel cell cathode gas path system to operate in a third mode, in which the first bypass valve (19) is in a closed state, the flow control valve (12) is in a first valve position state, and the coolant pump drives the coolant at a flow rate higher than or equal to a second preset flow rate, the second preset flow rate being greater than the first preset flow rate; and / or, the controller is adapted to control the fuel cell cathode gas path system to operate in a fourth mode, in which the first bypass valve (19) is in a closed state, the flow control valve (12) is in a state between the first valve position and a second valve position, and the coolant pump drives the coolant at a flow rate higher than or equal to a second preset flow rate, the second preset flow rate being greater than the first preset flow rate. And / or, the controller is adapted to control the fuel cell cathode gas path system to operate in a fifth mode, in which the first bypass valve (19) is in a closed state, the flow control valve (12) is in the second valve position state, and the charge air cooler does not cool the cathode gas.

9. The fuel cell cathode gas gas path system according to claim 7, wherein, The flow control valve (12) comprises a first butterfly valve plate and a second butterfly valve plate, the first butterfly valve plate is adapted to control the first gas outlet (121) to be connected or disconnected with the gas inlet, and the second butterfly valve plate is adapted to control the second gas outlet (122) to be connected or disconnected with the gas inlet; the first butterfly valve plate and the second butterfly valve plate are driven to rotate by the same rotary brake.

10. A fuel cell, wherein, A fuel cell cathode gas path system comprising any one of claims 1-9.

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