A fuel cell system

Abstract

The application relates to the field of fuel cell gas-liquid separation structures and discloses a fuel cell system, a hydrogen storage device of which is connected with a stack, a pressure reducing valve, a control valve, a driving member and a sensor being sequentially arranged on a connecting pipeline between the hydrogen storage device and the stack, the stack being connected with a gas-liquid separation device, an air inlet interface and an air outlet interface, the gas-liquid separation device being connected with the driving member, and the gas-liquid separation device being connected with a tail discharge valve. The application provides an integrated gas-liquid separation device which is applied to a hydrogen side system of a fuel cell, a secondary water separation cavity being additionally arranged on the top of a primary water separation cavity, so that the gas-liquid mixture after primary water separation reenters the secondary water separation cavity to realize secondary water separation, and the efficiency of gas-liquid separation is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fuel cell gas-liquid separation structure, and particularly provides a fuel cell system. BACKGROUND

[0002] A hydrogen reflux system is usually provided on the hydrogen side of a fuel cell, that is, the hydrogen mixture discharged from the fuel cell is driven by a hydrogen circulation pump (or an ejector) to flow back to the hydrogen inlet pipe of the fuel cell stack and is mixed with the newly supplied hydrogen to enter the fuel cell stack. The hydrogen mixture discharged from the fuel cell stack mainly contains hydrogen, nitrogen and water, and the water is usually in a gas-liquid mixed form, containing both water vapor and liquid water.

[0003] If the liquid water in the discharged mixture cannot be separated in time, the hydrogen reflux path will bring it back to the inlet of the fuel cell stack, which will affect the humidity control of the fuel cell stack and even cause water blockage in the fuel cell stack.

[0004] According to the use and demand, the commonly used gas-liquid separation devices are divided into centrifugal type, inertial force / gravity separation, filter element type and the like. Among them, the inertial force / gravity separation mainly utilizes the difference in density characteristics of the gas phase and liquid phase in the separated gas-liquid mixture, and after the gas phase and liquid phase are affected by the inertial force and gravity in the flow process of the gas-liquid separation device, the flow trajectories of the gas phase and liquid phase are different, forming a gas gathering area and a liquid gathering area. The inertial / gravity gas-liquid separation does not need additional driving energy, has small flow loss and high operation reliability. However, the design of the inertial / gravity gas-liquid separation device mainly relies on the inertial force and gravity of the fluid to realize gas-liquid separation, and usually the gas-liquid separation efficiency is low and a large space is required for gas-liquid separation.

[0005] The load of the fuel cell system for vehicle changes greatly, the running shaking range of the vehicle is large, and the gas-liquid separation efficiency is greatly disturbed by factors such as gas flow transient change and liquid level shaking. Under some harsh conditions, the fuel cell needs to operate below -30 degrees, and under such conditions, the liquid water in the water separation structure is easy to freeze and block the gas flow channel. One of the solutions is to integrate the water separation structure in the end plate of the fuel cell stack, and use the heat generated by the fuel cell stack to heat the water separation structure. SUMMARY

[0006] In order to solve the problems of large volume, high space arrangement requirement and low gas-liquid separation efficiency of the prior art gas-liquid separation structure, the present application provides a fuel cell system.

[0007] The technical scheme of the present application is as follows:

[0008] The utility model provides a kind of fuel cell system, the hydrogen storage device is connected with electric pile, sequentially be provided with pressure reducing valve, control valve, driving member and sensor on the connecting pipeline between hydrogen storage device and electric pile, the electric pile is connected with gas-liquid separation device, into the electric pile air interface and the electric pile air interface, the gas-liquid separation device is connected, and the gas-liquid separation device is connected with tail valve.

[0009] Further, the gas-liquid separation device includes a primary water separation cavity and a secondary water separation cavity. The secondary water separation cavity is connected with a secondary water separation gas-liquid mixture inlet. The secondary water separation gas-liquid mixture inlet is arranged at the top of the primary water separation cavity. The secondary water separation cavity is connected with the primary water separation cavity through the secondary water separation gas-liquid mixture inlet. The secondary water separation cavity is connected with a gaseous mixed gas outlet.

[0010] Further, the secondary water separation cavity is provided with an inclined bottom surface. The inclination angle of the inclined bottom surface is at least greater than 15°.

[0011] Further, the secondary water separation cavity is provided with a channel. The channel is connected with the inclined bottom surface. The inclined bottom surface is inclined towards the channel. An end face baffle is arranged above the channel. The end face baffle is arranged below the gaseous mixed gas outlet. The secondary water separation cavity is communicated with the primary water separation cavity through the channel.

[0012] Further, the secondary water separation gas-liquid mixture inlet is provided with a secondary water separation baffle and a side plate. The secondary water separation baffle is connected with the secondary water separation cavity. The side plate is connected with the primary water separation cavity.

[0013] Further, the secondary water separation gas-liquid mixture inlet is two groups. The two groups are respectively connected with two side edges of the secondary water separation cavity and are connected with the primary water separation cavity.

[0014] Further, the primary water separation cavity is connected with a primary water separation gas-liquid mixture inlet and a liquid discharge port. The primary water separation gas-liquid mixture inlet is arranged at the top of the primary water separation cavity. The primary water separation gas-liquid mixture inlet is provided with a primary water separation baffle. The primary water separation baffle is connected with the secondary water separation gas-liquid mixture inlet. The liquid discharge port is arranged at the bottom of the primary water separation cavity.

[0015] Further, the primary water separation gas-liquid mixture inlet is two groups. The two groups are respectively connected with the primary water separation cavity and are arranged at two sides of the top of the primary water separation cavity.

[0016] Further, the two groups of primary water separation gas-liquid mixture inlets of the primary water separation cavity are connected with the hydrogen gas outlet of the electric pile. The liquid discharge port of the primary water separation cavity is connected with the tail valve. The gaseous mixed gas outlet of the secondary water separation cavity is connected with the backflow inlet of the driving member.

[0017] Further, the driving member is any one of a hydrogen reflux pump or an ejector.

[0018] The present application at least includes the following beneficial effects:

[0019] (1) An integrated gas-liquid separation device is provided, which is applied to a hydrogen side system of a fuel cell, a secondary water separation cavity is additionally arranged at the top of a primary water separation cavity, and the gas-liquid mixture after primary water separation is introduced into the secondary water separation cavity to realize secondary water separation, so that the efficiency of gas-liquid separation is improved;

[0020] (2) The secondary water separation gas-liquid mixture inlet of the secondary water separation cavity is arranged at the top of the primary water separation cavity, and is less disturbed by liquid level fluctuation, so that the gas-liquid separation effect is stable;

[0021] (3) The secondary water separation cavity is provided with a downwardly inclined bottom surface, so that the liquid water in the secondary water separation cavity is easily collected;

[0022] (4) The primary water separation cavity and the secondary water separation cavity are connected through a channel, so that the liquid water in the secondary water separation cavity is collected into the primary water separation cavity, and then is discharged through a liquid discharge port, without increasing an additional water discharge device, so that the cost is saved;

[0023] (5) The primary water separation cavity and the secondary water separation cavity both adopt a baffle structure, so that the processing technology is simple, and the device is convenient to use. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a schematic diagram of the connection of the overall structure of the present application.

[0025] Figure 2 It is a side view of the overall structure of the gas-liquid separation device of the present application.

[0026] Figure 3 It is a front view of embodiment one of the present application.

[0027] Figure 4 It is a front view of embodiment two of the present application.

[0028] Figure 5 It is a side view of the gas-liquid separation device of the present application.

[0029] Among them:

[0030] 1-hydrogen storage device;

[0031] 2-pressure reducing valve;

[0032] 3-control valve;

[0033] 4-driving member;

[0034] 5-sensor;

[0035] 6-stack;

[0036] 7-air inlet interface of stack;

[0037] 8-air outlet interface of stack;

[0038] 9-gas-liquid separation device; 901-primary water separation cavity; 902-secondary water separation cavity; 903-secondary water separation gas-liquid mixture inlet; 904-gaseous mixed gas outlet; 905-secondary water separation baffle; 906-side plate; 907-channel; 908-end face baffle; 909-inclined bottom surface; 910-primary water separation gas-liquid mixture inlet; 911-liquid discharge port; 912-primary water separation baffle.

[0039] 10-tail discharge valve. DETAILED DESCRIPTION

[0040] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0041] According to Figures 1 to 2 As shown in FIG. 1, the present application provides a fuel cell system, a hydrogen storage device 1 is connected with a stack 6, a pressure reducing valve 2, a control valve 3, a driving member 4 and a sensor 5 are sequentially arranged on a connecting pipeline between the hydrogen storage device 1 and the stack 6, the stack 6 is connected with a gas-liquid separation device 9, an air inlet interface 7 of stack and an air outlet interface 8 of stack, the gas-liquid separation device 9 is connected with the driving member 4, and the gas-liquid separation device 9 is connected with a tail discharge valve 10.

[0042] The gas-liquid separation device 9 comprises a primary water separation cavity 901 and a secondary water separation cavity 902, the secondary water separation cavity 902 is connected with a secondary water separation gas-liquid mixture inlet 903, the secondary water separation gas-liquid mixture inlet 903 is arranged at the top of the primary water separation cavity 901, the secondary water separation cavity 902 is connected with the primary water separation cavity 901 through the secondary water separation gas-liquid mixture inlet 903, and the secondary water separation cavity 902 is connected with a gaseous mixed gas outlet 904.

[0043] Embodiment one

[0044] According to Figure 1As shown, the present application provides a fuel cell system, the hydrogen storage device 1 is connected with the stack 6, a pressure reducing valve 2, a control valve 3, a driving member 4 and a sensor 5 are sequentially arranged on the connecting pipeline between the hydrogen storage device 1 and the stack 6, the stack 6 is connected with a gas-liquid separation device 9, an air inlet interface 7 and an air outlet interface 8 of the stack, the gas-liquid separation device 9 is connected with the driving member 4, and the gas-liquid separation device 9 is connected with a tail valve 10; the control valve 3 is a hydrogen control valve, and the sensor 5 is a pressure sensor.

[0045] According to Figure 2 、 Figure 3 and Figure 5 As shown, the present embodiment provides a gas-liquid separation device 9 which is externally connected to the stack, comprising a primary water separation cavity 901 and a secondary water separation cavity 902, the secondary water separation cavity 902 is arranged above the primary water separation cavity 901, the primary water separation cavity 901 is provided with a primary water separation gas-liquid mixture inlet 910 and a liquid discharge port 911, the primary water separation gas-liquid mixture inlet 910 is arranged on the top side of the primary water separation cavity 901, the primary water separation gas-liquid mixture inlet 910 is connected with a secondary water separation gas-liquid mixture inlet 903, and the secondary water separation gas-liquid mixture inlet 903 is connected with the secondary water separation cavity 902; the liquid discharge port 911 is arranged at the bottom of the primary water separation cavity 901.

[0046] The primary water separation gas-liquid mixture inlet 910 is provided with a primary water separation baffle 912 on the side close to the secondary water separation gas-liquid mixture inlet 903, the primary water separation baffle 912 is connected with the secondary water separation gas-liquid mixture inlet 903, and the primary water separation baffle 912 is used for primary gas-liquid separation.

[0047] The secondary water separation gas-liquid mixture inlet 903 comprises two groups and is arranged on the two side edges of the secondary water separation cavity 902, the secondary water separation gas-liquid mixture inlet 903 is provided with a secondary water separation baffle 905 on the side close to the secondary water separation cavity 902, the secondary water separation baffle 905 is used for secondary gas-liquid separation, the secondary water separation baffle 905 is connected with the secondary water separation cavity 902, and the secondary water separation gas-liquid inlet 903 is further provided with a side plate 906, the two ends of the side plate 906 are respectively connected with the primary water separation cavity 901 and the secondary water separation cavity 902, one end of the side plate 906 connected with the primary water separation cavity 901 extends to the middle upper part of the primary water separation cavity 901, and the two side plates 906 form a through slot in the middle upper part of the primary water separation cavity 901.

[0048] The secondary water drainage cavity 902 is provided with a gaseous mixed gas outlet 904 in the direction perpendicular to the primary water drainage gas-liquid mixture inlet 910, the bottom surface of the secondary water drainage cavity 902 is an inclined bottom surface 909, which is inclined downward in the direction of the gaseous mixed gas outlet 904, and the inclination angle should not be less than 15° in consideration of the vehicle running acceleration and the situation of drainage under harsh conditions such as inclination, and the inclined bottom of the inclined bottom surface 909 is provided with a channel 907, the secondary water drainage cavity 902 is connected with the primary water drainage cavity 901 through the channel 907, and the channel 907 is used for supplying the liquid water separated by the secondary gas-liquid separation to be drained from the secondary water drainage cavity 902 into the primary water drainage cavity 901; and the inclined bottom surface 909 is arranged above the through groove formed by the two side plates 906.

[0049] The channel 907 is provided with an end face baffle 908 above the channel 907, the end face baffle 908 is arranged below the gaseous mixed gas outlet 904, and the end face baffle 908 and the inclined bottom surface 909 form a throttling throat, and the flow area of the throat can be determined according to the pressure difference between the primary water drainage cavity 901 and the secondary water drainage cavity 902 and the drainage amount of the secondary water drainage cavity 902.

[0050] The primary water drainage cavity 901 is connected with the hydrogen out-stack port of the stack 6 through the primary water drainage gas-liquid mixture inlet 910, the drainage port 911 of the primary water drainage cavity 901 is connected with the tail discharge valve 10, and the gaseous mixed gas outlet 904 of the secondary water drainage cavity 902 is connected with the backflow inlet of the driving member 4.

[0051] The driving member 4 is any one of a hydrogen backflow pump or an ejector.

[0052] Embodiment two

[0053] According to Figure 1 It is shown that the application provides a fuel cell system, the hydrogen storage device 1 is connected with the stack 6, the connecting pipeline between the hydrogen storage device 1 and the stack 6 is sequentially provided with a pressure reducing valve 2, a control valve 3, a driving member 4 and a sensor 5, the stack 6 is connected with a gas-liquid separation device 9, an in-stack air interface 7 and an out-stack air interface 8, the gas-liquid separation device 9 is connected with the driving member 4, and the gas-liquid separation device 9 is connected with a tail discharge valve 10; the control valve 3 is a hydrogen control valve, and the sensor 5 is a pressure sensor.

[0054] According to Figure 2 , Figure 4 And Figure 5As shown, the embodiment provides a gas-liquid separation device 9 which can be integrated in a hydrogen outlet manifold of a double stack module, including a primary water separation cavity 901 and a secondary water separation cavity 902, the secondary water separation cavity 902 is arranged above the primary water separation cavity 901, the primary water separation cavity 901 is provided with two primary water separation gas-liquid mixture inlets 910 and a liquid outlet, the primary water separation gas-liquid mixture inlets 910 are arranged on the top side of the primary water separation cavity 901, the primary water separation gas-liquid mixture inlets 910 are connected with secondary water separation gas-liquid mixture inlets 903, the secondary water separation gas-liquid mixture inlets 903 are connected with the secondary water separation cavity 902; the liquid outlet 911 is arranged at the bottom of the primary water separation cavity 901.

[0055] The side of the primary water separation gas-liquid mixture inlet 910 close to the secondary water separation gas-liquid mixture inlet 903 is provided with a primary water separation baffle 912, the primary water separation baffle 912 is connected with the secondary water separation gas-liquid mixture inlet 903, the primary water separation baffle 912 is used for primary gas-liquid separation.

[0056] The secondary water separation gas-liquid mixture inlet 903 includes two groups, which are arranged on the two side edges of the secondary water separation cavity 902, the secondary water separation gas-liquid mixture inlet 903 is provided with a secondary water separation baffle 905 on the side close to the secondary water separation cavity 902, the secondary water separation baffle 905 is used for secondary gas-liquid separation, the secondary water separation baffle 905 is connected with the secondary water separation cavity 902, the secondary water separation gas-liquid mixture inlet 903 is further provided with side plates 906, the two ends of the side plates 906 are respectively connected with the primary water separation cavity 901 and the secondary water separation cavity 902, one end of the side plate 906 connected with the primary water separation cavity 901 extends to the middle upper part of the primary water separation cavity 901, and the two side plates 906 form a through slot in the middle upper part of the primary water separation cavity 901.

[0057] The secondary water separation cavity 902 is provided with a gaseous mixture outlet 904 in the direction perpendicular to the primary water separation gas-liquid mixture inlet 910, the bottom surface of the secondary water separation cavity 902 is an inclined bottom surface 909, which is inclined downward in the direction of the gaseous mixture outlet 904, considering the situation of drainage under harsh conditions such as vehicle running acceleration and inclination, the inclination angle should not be less than 15°, the inclined bottom of the inclined bottom surface 909 is provided with a channel 907, the secondary water separation cavity 901 is connected with the primary water separation cavity 901 through the channel 907, the channel 907 supplies the liquid water separated by the secondary gas-liquid separation from the secondary water separation cavity 902 to the primary water separation cavity 901; the inclined bottom surface 909 is arranged above the through slot formed by the two side plates 906.

[0058] The channel 907 is provided with an end face baffle 908, which is arranged below the gaseous mixture outlet 904 and forms a throttling throat with the inclined bottom surface 909. The flow area of the throat can be determined according to the pressure difference between the primary water separation cavity 901 and the secondary water separation cavity 902 and the liquid discharge amount of the secondary water separation cavity 902.

[0059] The two groups of primary water separation gas-liquid mixture inlets 910 of the primary water separation cavity 901 are connected with the hydrogen outlet of the stack 6, the liquid discharge port 911 of the primary water separation cavity 901 is connected with the tail discharge valve 10, and the gaseous mixture outlet 904 of the secondary water separation cavity 902 is connected with the return inlet of the driving member 4.

[0060] The driving member 4 is any one of a hydrogen return pump or an ejector.

[0061] A hydrogen return system is usually provided on the hydrogen side of a fuel cell, that is, the hydrogen mixture discharged from the stack is driven to return to the hydrogen inlet pipeline of the stack by a hydrogen circulation pump (or an ejector) and is mixed with newly supplied hydrogen to enter the stack. The hydrogen mixture discharged from the stack mainly contains hydrogen, nitrogen and water, and the water is usually in the form of gas-liquid mixture, containing water vapor and liquid water. If the liquid water in the mixture discharged from the stack cannot be separated in time, the hydrogen return pipeline will bring it back to the inlet of the stack, which will affect the humidity control of the stack and even cause water blockage in the stack. In order to remove the liquid water droplets contained in the hydrogen mixture discharged from the stack of the fuel cell, the hydrogen outlet of the stack is usually provided with a gas-liquid separation structure or device. The present application provides an integrated gas-liquid separation device applied to the hydrogen side system of a fuel cell. A secondary water separation cavity is additionally arranged on the top of a primary water separation cavity. The gas-liquid mixture is subjected to primary water separation in the primary water separation cavity and then enters the secondary water separation cavity to be subjected to secondary water separation, so that the efficiency of gas-liquid separation is improved. The secondary water separation gas-liquid mixture inlet of the secondary water separation cavity is arranged at the top of the primary water separation cavity, so that the liquid level is less disturbed and the gas-liquid separation effect is stable. In order to facilitate the collection of the liquid water in the secondary water separation cavity, an inclined bottom surface is arranged in the secondary water separation cavity, the liquid water in the secondary water separation cavity is collected into the primary water separation cavity through the channel arranged between the primary water separation cavity and the secondary water separation cavity, and finally discharged through the liquid discharge port.

[0062] The above description is only an embodiment of the present application and does not limit the patent range of the present application. Any equivalent structure or equivalent process conversion or direct or indirect application in other related technical fields based on the content of the specification and drawings of the present application are also included in the patent protection range of the present application.

Claims

1. A fuel cell system characterized by comprising: The hydrogen storage device is connected with an electric pile, a pressure reducing valve, a control valve, a driving member and a sensor are sequentially arranged on a connecting pipeline between the hydrogen storage device and the electric pile, the electric pile is connected with a gas-liquid separation device, an air inlet and an air outlet, the gas-liquid separation device is connected with the driving member, and the gas-liquid separation device is connected with a tail discharge valve. The gas-liquid separation device comprises a primary water separation cavity and a secondary water separation cavity, the secondary water separation cavity is connected with a secondary water separation gas-liquid mixture inlet, the secondary water separation gas-liquid mixture inlet is arranged at the top of the primary water separation cavity, the secondary water separation cavity is connected with the primary water separation cavity through the secondary water separation gas-liquid mixture inlet, and the secondary water separation cavity is connected with a gaseous mixed gas outlet. The secondary water separation cavity is provided with an inclined bottom surface, and the inclination angle of the inclined bottom surface is 15°. The secondary water separation cavity is provided with a channel, the channel is connected with the inclined bottom surface, the inclined bottom surface is inclined to the direction of the channel, an end face baffle is arranged above the channel, the end face baffle is arranged below the gaseous mixed gas outlet, and the secondary water separation cavity is communicated with the primary water separation cavity through the channel. The end face baffle and the inclined bottom surface form a throttling throat, and the flow area of the throttling throat is determined according to the pressure difference between the primary water separation cavity and the secondary water separation cavity and the liquid discharge amount of the secondary water separation cavity. The primary water separation cavity is connected with a primary water separation gas-liquid mixture inlet and a liquid discharge port, the primary water separation gas-liquid mixture inlet is arranged at the top of the primary water separation cavity, the primary water separation gas-liquid mixture inlet is provided with a primary water separation baffle, the primary water separation baffle is connected with the secondary water separation gas-liquid mixture inlet, and the liquid discharge port is arranged at the bottom of the primary water separation cavity.

2. A fuel cell system according to claim 1, characterised in that: The secondary water separation gas-liquid mixture inlet is provided with a secondary water separation baffle and a side plate, the secondary water separation baffle is connected with the secondary water separation cavity, and the side plate is connected with the primary water separation cavity.

3. A fuel cell system according to claim 1, wherein: The secondary water separation gas-liquid mixture inlet is provided with a secondary water separation baffle and a side plate, the secondary water separation baffle is connected with the secondary water separation cavity, and the side plate is connected with the primary water separation cavity.

4. The fuel cell system of claim 1, wherein: The secondary water separation gas-liquid mixture inlet is provided with a secondary water separation baffle and a side plate, the secondary water separation baffle is connected with the secondary water separation cavity, and the side plate is connected with the primary water separation cavity.

5. A fuel cell system according to any one of claims 1-4, characterized in that: The two groups of primary water separation gas-liquid mixture inlets of the primary water separation cavity are connected with hydrogen outlets of the electric pile, the liquid discharge port of the primary water separation cavity is connected with the tail discharge valve, and the gaseous mixed gas outlet of the secondary water separation cavity is connected with a reflux inlet of the driving member.

6. A fuel cell system according to claim 1, wherein: The driving member is any one of a hydrogen reflux pump or an ejector.

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