Tail end plate for fuel cell with tail end drainage function and fuel cell stack

Abstract

The utility model discloses a tail end plate for a fuel cell with a tail end drainage function, the tail end plate is used for clamping and fixing a fuel cell unit together with a front end plate when the tail end plate is assembled into a fuel cell stack, and one side of the fuel cell unit close to the tail end plate is provided with a public hydrogen exhaust channel and a public air exhaust channel. After the tail end plate is assembled, a hydrogen water outlet and drainage mechanism is arranged at the position, corresponding to the public hydrogen exhaust channel, of the tail end plate, and an air water outlet and drainage mechanism is arranged at the position, corresponding to the public air exhaust channel, of the tail end plate. The utility model also provides a fuel cell stack. The tail end plate for the fuel cell provided by the utility model can solve the problem that the tail end of the fuel cell is easy to accumulate water and the drainage capacity is insufficient.

Description

Technical Field

[0001] The utility model belongs to the technical field of fuel cells, and in particular relates to a tail end plate for a fuel cell with a tail end drainage function and a fuel cell stack. Background Art

[0002] A fuel cell is a power generation device that is composed of multiple fuel cell bipolar plate monomers and membrane electrode monomers stacked on each other, and then connected in series with the front end plate and the tail end plate. Among them, the bipolar plate is used to separate the reaction gas, collect and conduct current, support the membrane electrode, and discharge the waste heat generated by the battery reaction; the membrane electrode is used to separate the reaction gas, catalyze the reactants to undergo chemical reactions on its surface, transfer protons, and thus generate current and generate electricity. The front end plate and the tail end plate are important components that play the role of clamping and fixing the bipolar plate and the membrane electrode, wherein the front end plate is the fluid inlet and outlet end plate, and the tail end plate is the plugging end plate. The bipolar plate and the membrane electrode are stacked on each other and form the fuel cell's common air inlet channel and common air outlet channel with the front end plate and the tail end plate, including the air inlet common channel, the hydrogen inlet common channel, the air outlet common channel, the hydrogen inlet common channel, and the coolant inlet and outlet common channel. The water generated by the cathode reaction and the water that enters the anode through the membrane electrode enter the respective air outlet common channel and hydrogen outlet common channel with the air and hydrogen, and then are discharged after the stack interface is connected to the system. Due to the effect of resistance, the pressure of the gas will weaken after passing through the common intake channel, and the pressure will further weaken after entering the bipolar plate flow field. When the gas enters the tail end of the fuel cell, the pressure of the monomer will be the weakest, making the driving force of the air and water discharged into the common outlet channel the smallest. Then, the tail end of the fuel cell is prone to water accumulation, resulting in edge effect, which is specifically manifested as low monomer voltage in one or several sections of the tail end, resulting in poor uniformity of the fuel cell monomer. With the accumulation of time, it becomes more and more serious, and reverse polarity and membrane electrode perforation occur, thus affecting the life of the fuel cell.

[0003] Patent document CN219441070U discloses an air filter structure for a fuel cell, which includes an air filter housing, an air filter inlet channel is provided in the middle of the front end of the air filter housing, and an air filter outlet channel is provided in the middle of the rear end of the air filter housing; characterized in that: a humidity sensor for detecting air humidity is provided at the upper front end of the side wall of the air filter housing, and a drain valve is provided at the lower rear end of the side wall of the air filter housing; a baffle extending to both sides of the air filter housing is provided inside the air filter housing to divide the inside of the air filter housing into a first air passage and a second air passage, a first filter element is provided in the first air passage, a second filter element is provided in the second air passage, and the thickness of the second filter element is greater than that of the first filter element; and a valve for controlling the opening and closing of the first air passage and the second air passage is provided at the front end of the baffle, and the valve is controlled by a motor. The device has the problem of insufficient tail pressure. Utility Model Content

[0004] The utility model aims to provide a tail end plate for a fuel cell and a fuel cell stack with a tail end drainage function, so as to solve the problem that water is easily accumulated at the tail end of the fuel cell and the drainage capacity is insufficient.

[0005] In order to achieve the first invention purpose of the utility model, a tail end plate for a fuel cell with a tail end drainage function is provided, wherein the tail end plate is used to clamp and fix the fuel cell unit together with the front end plate when assembling into a fuel cell stack, and the fuel cell unit has a common hydrogen exhaust channel and a common air exhaust channel on the side close to the tail end plate, and the tail end plate is provided with a hydrogen outlet and drainage mechanism corresponding to the common hydrogen exhaust channel and an air outlet and drainage mechanism corresponding to the common air exhaust channel after assembly;

[0006] The hydrogen outlet and drainage mechanism and the air outlet and drainage mechanism both include a drainage groove arranged on the tail end plate for abutting against one side of the fuel cell unit and for receiving moisture, a drainage hole groove away from the side of the fuel cell unit and for drainage, and a drainage hole for connecting the drainage groove and the drainage hole groove, the drainage hole groove is provided with a sealing cover, the sealing cover is provided with a drainage pipe connecting the outside with the inside of the drainage hole groove, one end of the drainage pipe located in the drainage hole groove is connected to the bottom surface of the drainage hole groove to form a drainage cavity, the drainage holes are arranged around the drainage pipe, and the end circumferential surface of the end of the drainage pipe extending into the drainage hole groove is provided with capillary pores for introducing water into the drainage pipe.

[0007] Specifically, the tail end plate is placed horizontally when the fuel cell is in use and is located at the lower end of the fuel cell. The drainage groove is used to receive the side wall of the fuel cell unit that discharges water, and is a sloped surface for diversion.

[0008] Specifically, the notch of the drainage hole groove is provided with a mounting groove adapted to the sealing cover, and the mounting groove is provided with a threaded mounting hole for positioning and fixing to improve the sealing performance.

[0009] Specifically, there are a plurality of threaded mounting holes, and the plurality of threaded holes are arranged around the mounting groove.

[0010] Specifically, there are a plurality of capillary pores, and the plurality of capillary pores are arranged along the circumference of the drainage pipe to improve drainage efficiency.

[0011] In order to achieve the second invention purpose of the utility model, a fuel cell stack is provided, including a front end plate, a rear end plate, and a fuel cell unit clamped and fixed between the front end plate and the rear end plate, wherein the rear end plate uses the above-mentioned rear end plate for fuel cells with a rear end drainage function.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] The drainage cavity formed by the sealing cover and the drainage hole groove and the capillary pores at the end of the drainage pipe are used to discharge the waste water, thereby preventing water accumulation at the end of the fuel cell;

[0014] Prevent the low edge effect of the fuel cell tail end to improve the uniformity of the battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A three-dimensional schematic diagram of the tail end plate provided in this embodiment;

[0016] Figure 2 A three-dimensional schematic diagram of the drainage groove of the tail end plate provided in this embodiment;

[0017] Figure 3 A cross-sectional view of the drainage groove provided for this embodiment;

[0018] Figure 4 A cross-sectional view of the drainage hole groove provided in this embodiment;

[0019] Figure 5 A schematic diagram of a sealing cover provided in this embodiment;

[0020] Figure 6 A schematic diagram of the assembly of the drainage hole groove and the sealing cover provided in this embodiment;

[0021] In the figure, 1, tail end plate; 2, front end plate; 3, bipolar plate; 4, membrane electrode; 5, drainage groove; 6, slope surface; 7, bottom groove; 8, drainage hole groove; 9, drainage hole; 10, mounting groove; 11, sealing ring; 12, threaded mounting hole; 13, drainage pipe; 14, screw; 15, sealing cover; 16, drainage cavity; 17, capillary pores; 18, positioning hole. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. The components of the embodiment of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiment of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the utility model.

[0023] like Figure 1 As shown, a tail end plate for a fuel cell with a tail end drainage function is provided in this embodiment. The tail end plate 1 is used to clamp and fix the fuel cell unit together with the front end plate 2 when assembling into a fuel cell stack. The fuel cell unit includes a bipolar plate 3 and a membrane electrode 4. The fuel cell unit has a common hydrogen exhaust channel and a common air exhaust channel on the side adjacent to the tail end plate 1.

[0024] like Figure 2 and Figure 3 As shown, after assembly, the tail end plate 1 is provided with a hydrogen outlet and drainage mechanism at the corresponding common hydrogen exhaust channel and an air outlet and drainage mechanism at the corresponding common air exhaust channel. The hydrogen outlet and drainage mechanism and the air outlet and drainage mechanism both include a drainage groove 5 provided on the tail end plate 1 for abutting against one side of the fuel cell unit and for receiving moisture. The tail end plate 1 is placed horizontally when the fuel cell is in use and is located at the lower end of the fuel cell. The drainage groove 5 is used to receive the side wall of the fuel cell unit's discharged water, and has a slope surface 6 for diversion.

[0025] like Figure 4 As shown, a drainage hole groove 8 for draining water is provided away from one side of the fuel cell unit, and the drainage groove 5 is connected with the drainage hole groove 8 through a drainage hole 9, through which waste water of the fuel cell is introduced into the drainage hole groove 8.

[0026] The drain hole slot 8 has a mounting slot 10 at its slot opening. The mounting slot 10 has a threaded mounting hole 12 for positioning and fixing, and has a sealing ring 11 .

[0027] like Figure 5 and Figure 6As shown, the drainage hole groove 8 has a sealing cover 15, and the sealing cover 15 is provided with a drainage pipe 13 connecting the outside with the inside of the drainage hole groove 8. One end of the drainage pipe 13 located in the drainage hole groove 8 is connected to the bottom surface of the drainage hole groove 8 to form a drainage cavity 16. The drainage hole 9 is arranged around the drainage pipe 13. The end circumferential surface of the drainage pipe 13 extending into the drainage hole groove 8 is provided with capillary pores 17 for introducing water into the drainage pipe 13.

[0028] The capillary pores 17 proposed in this embodiment have a capillary effect, which can guide the waste water remaining in the drainage cavity 13 into the drainage pipe 13, thereby further discharging the waste water out of the fuel cell.

[0029] After the sealing cover 15 is arranged in the installation groove 10 , the screws 14 are passed through the positioning holes 18 of the sealing cover 15 and are connected and fixed to the threaded installation holes 12 on the installation groove 10 .

[0030] This embodiment also provides a fuel cell stack, including a front end plate 2, a rear end plate 1, and a fuel cell unit clamped and fixed between the front end plate and the rear end plate, and the specific drainage method is as follows:

[0031] Most of the water discharged from the fuel cell into the public channel is discharged from the discharge port of the front end plate. The part that is difficult to discharge at the tail end enters the drainage groove, enters the drainage hole along the bottom groove of the drainage groove, and then enters the drainage cavity between the drainage hole groove and the drainage pipe. The non-opening area at the bottom of the drainage hole groove forms a capillary effect with the capillary tube and the water in the drainage cavity. The water is sucked out by the capillary pores and discharged to the outside of the fuel cell.

[0032] In addition, the terms "upper", "lower", "inner", "outer", "front", "rear" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. Unless otherwise specifically stated, the relative steps, numerical expressions and values ​​of the components and steps described in these embodiments do not limit the scope of the present invention.

[0033] Of course, the above description is only a specific embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. All equivalent changes or modifications made according to the structure, features and principles described in the patent application scope of the present invention should be included in the patent application scope of the present invention.

Claims

1. A tail end plate for a fuel cell with a tail end drainage function, the tail end plate is used to clamp and fix the fuel cell unit together with the front end plate when assembling into a fuel cell stack, and the fuel cell unit has a common hydrogen exhaust channel and a common air exhaust channel on the side close to the tail end plate, characterized in that: After assembly, the tail end plate is provided with a hydrogen outlet and drainage mechanism at a position corresponding to the common hydrogen exhaust passage and an air outlet and drainage mechanism at a position corresponding to the common air exhaust passage; The hydrogen outlet and drainage mechanism and the air outlet and drainage mechanism both include a drainage groove arranged on the tail end plate for abutting against one side of the fuel cell unit and for receiving moisture, a drainage hole groove away from the side of the fuel cell unit and for drainage, and a drainage hole for connecting the drainage groove and the drainage hole groove, the drainage hole groove is provided with a sealing cover, the sealing cover is provided with a drainage pipe connecting the outside with the inside of the drainage hole groove, one end of the drainage pipe located in the drainage hole groove is connected to the bottom surface of the drainage hole groove to form a drainage cavity, the drainage holes are arranged around the drainage pipe, and the end circumferential surface of the end of the drainage pipe extending into the drainage hole groove is provided with capillary pores for introducing water into the drainage pipe.

2. The tail end plate for a fuel cell with a tail end drainage function according to claim 1, characterized in that: The tail end plate is placed horizontally when the fuel cell is in use and is located at the lower end of the fuel cell. The side wall of the drainage groove, which is used to receive the water discharged from the fuel cell unit, is a slope surface for diversion.

3. The tail end plate for a fuel cell with a tail end drainage function according to claim 1, characterized in that: The notch of the drainage hole groove is provided with a mounting groove matched with the sealing cover, and the mounting groove is provided with a threaded mounting hole for positioning and fixing.

4. The tail end plate for a fuel cell with a tail end drainage function according to claim 3, characterized in that: There are multiple threaded mounting holes, and the multiple threaded holes are arranged around the mounting groove.

5. The tail end plate for a fuel cell with a tail end drainage function according to claim 1, characterized in that: There are a plurality of capillary pores, and the capillary pores are arranged along the circumference of the drain pipe.

6. A fuel cell stack, comprising a front end plate, a rear end plate, and a fuel cell unit clamped and fixed between the front end plate and the rear end plate, characterized in that: The tail end plate is the tail end plate for a fuel cell having a tail end drainage function as claimed in any one of claims 1 to 5.

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