Graphite anode plate for PEMFC

Abstract

The invention discloses a graphite anode plate for a PEMFC, and relates to the technical field of fuel cells, the graphite anode plate comprises a pole plate body, the pole plate body is provided with a hydrogen inlet and a hydrogen outlet which are respectively located at two ends of the pole plate body, and a flow field structure located at one side of the pole plate body is arranged between the hydrogen inlet and the hydrogen outlet; gas distribution areas are arranged between the hydrogen inlets and the flow field structures, each gas distribution area comprises a plurality of raised lines and bosses which are distributed in a staggered mode, and the length extension direction of the raised lines close to the hydrogen inlets and the flow field structures at the same time is perpendicular to the gas outlet direction of the hydrogen inlets; the length extension direction of the raised lines close to the hydrogen inlet but far away from the flow field structure is perpendicular to the gas inlet direction of the flow field structure, and the length extension direction of the raised lines far away from the hydrogen inlet but close to the flow field structure is parallel to the gas outlet direction of the hydrogen inlet; the structure can synchronize the speed and the flow of hydrogen in the hydrogen inlet when the hydrogen enters the gas inlet of the runner to the greatest extent.

Description

Technical Field

[0001] The invention relates to the technical field of fuel cells, and in particular to a graphite anode plate used for PEMFC. Background Art

[0002] In recent years, due to the acceleration of the global industrialization process, the consumption of fossil fuels has remained at a high level. However, in the process of energy conversion of fossil fuels, the global environment has deteriorated, such as the greenhouse effect and acid rain, which have significantly threatened human survival. Against the backdrop of the goal of carbon neutrality, vigorously developing clean energy is currently a top priority. Among them, hydrogen energy is the most important part of clean energy, and fuel cells are a key link in the hydrogen energy industry. In "Made in China 2025", my country has put forward a clear development plan for fuel cell vehicles and related technologies. At present, demonstration operations have been carried out in many places, which indicates that the fuel cell industry has formed a certain scale in my country.

[0003] Proton exchange membrane fuel cells (PEMFC) have the advantages of low pollution, high power density, high energy conversion efficiency, fast response to load changes, low noise, short start-up time and low operating temperature, making them one of the effective solutions to solve the environmental pollution, resource and energy shortage problems caused by the transportation industry. Proton exchange membrane fuel cells (PEMFC) are efficient energy conversion devices that directly convert chemical energy into electrical energy through the electrochemical reaction of hydrogen and oxygen. Because they do not require combustion during the power generation process and are not restricted by the Carnot cycle, they have the characteristics of high energy conversion rate and environmental friendliness. They have broad application prospects and huge potential, and are widely used in portable devices, transportation and fixed power generation.

[0004] The function of the bipolar plate is to effectively transmit current between cells, provide gas reactants, and provide structural support for the cell. The material of the bipolar plate must be impermeable, durable, corrosion-resistant, and a good conductor of electricity and heat. At present, the manufacturing materials of the bipolar plate are mainly composite materials, graphite or metal. The design of the reactant flow channel in BPs is one of the most active research areas in the development of fuel cell systems, because different reactant flow channel designs will affect the uniformity of gas distribution, the intensity of under-rib convection and the drainage performance, thereby affecting the output performance, life and energy consumption of the fuel cell. Therefore, many studies have been conducted to improve the flow channel on the substrate. However, the improvement of the flow channel structure can only play a role in the gas distribution after entering the flow channel. Before entering the flow channel, when the gas passes through the distribution area, there is often a distance difference between the outlet position of the distribution area entering the flow channel and the position of the gas inlet. Therefore, when the gas enters the flow channel, its flow velocity and flow rate are different, resulting in the overall reaction process being not uniform and stable when reacting in the flow field.

[0005] Therefore, it is necessary to provide a graphite anode plate for PEMFC so that the flow velocity and flow rate of the gas entering the flow field structure are in a uniform and stable state. Summary of the invention

[0006] The object of the present invention is to provide a graphite anode plate for PEMFC to solve the following technical problems:

[0007] How to make the hydrogen flow rate more uniform and stable when entering the flow channel structure in the anode plate?

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] A graphite anode plate for PEMFC, comprising a plate body, a hydrogen inlet and a hydrogen outlet respectively located at two ends of the plate body are provided on the plate body, a flow field structure located at one side of the plate body is provided between the hydrogen inlet and the hydrogen outlet; a gas distribution area is provided between the hydrogen inlet and the flow field structure, the gas distribution area is triangular, and the hydrogen inlet and the flow field structure are respectively located at two adjacent sides of the triangle;

[0010] The gas distribution area includes a plurality of staggered convex strips and bosses, wherein the length extension direction of the convex strips close to the hydrogen inlet and the flow field structure is perpendicular to the gas outlet direction of the hydrogen inlet, the length extension direction of the convex strips close to the hydrogen inlet but far from the flow field structure is perpendicular to the gas inlet direction of the flow field structure, and the length extension direction of the convex strips far from the hydrogen inlet but close to the flow field structure is parallel to the gas outlet direction of the hydrogen inlet.

[0011] In a further embodiment of the present invention, the length of the convex strip far from the hydrogen inlet but close to the flow field structure is shorter than the length of the convex strip near both the hydrogen inlet and the flow field structure, and the length of the convex strip near the hydrogen inlet but far from the flow field structure.

[0012] In a further embodiment of the present invention, a gas distribution area is also provided between the hydrogen outlet and the ridge channel, and the position distribution of the gas distribution area between the hydrogen outlet and the ridge channel is the same as the position distribution of the gas distribution area between the hydrogen inlet and the ridge channel.

[0013] In a further embodiment of the present invention, a plurality of hydrogen inlet gas distribution ports are provided between the hydrogen inlet and the corresponding gas distribution area, and a plurality of corresponding hydrogen outlet gas distribution ports are provided between the hydrogen outlet and the corresponding gas distribution area.

[0014] In a further embodiment of the present invention, the flow field structure includes a plurality of groups of ridges arranged in parallel and equidistantly, and a flow channel is formed between two adjacent ridges.

[0015] In a further embodiment of the present invention, the ridge is curved.

[0016] In a further embodiment of the present invention, the width of the ridge varies regularly.

[0017] In a further embodiment of the present invention, a plurality of water inlets and water outlets corresponding to the plurality of water inlets are provided on the electrode body, wherein the plurality of water inlets and water outlets are arranged in parallel on both sides of the flow field structure adjacent to the hydrogen inlet and the hydrogen outlet.

[0018] Beneficial effects of the present invention:

[0019] In the graphite anode plate for PEMFC of the present invention, when gas distribution is performed, hydrogen enters the gas distribution area from the hydrogen inlet, and first enters area one and area two. In area one, the flow direction of the hydrogen is perpendicular to the length extension direction of the convex strips. Therefore, the convex strips in area one can slow down the flow speed of the hydrogen to the maximum extent and delay the time for the hydrogen to enter the flow channel. In area two, the length extension direction of the convex strips is toward area three, so the hydrogen can be guided in the direction of area three. After the hydrogen enters area three from area two, the flow direction of the hydrogen is parallel to the length direction of the convex strips in area three. Therefore, the flow resistance of area three to the hydrogen is very small, and the speed of the hydrogen entering the flow channel can be accelerated. Based on this, the speed and flow rate of the hydrogen in the hydrogen inlet when entering the flow channel inlet can be synchronized to the maximum extent, ensuring that the movement speed of the hydrogen in the flow channel tends to be uniform and stable as a whole, thereby improving the effect of the electrochemical reaction of hydrogen with the membrane electrode in the ridge channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] Figure 1 It is a schematic structural diagram of a graphite anode plate for PEMFC of the present invention;

[0022] Figure 2 yes Figure 1 A is a schematic diagram of the enlarged structure of the middle part;

[0023] Figure 3 yes Figure 1 Schematic diagram of the enlarged structure of B.

[0024] In the figure: 100, electrode body; 101, hydrogen inlet; 1011, gas inlet distribution port; 102, hydrogen outlet; 1021, gas outlet distribution port; 103, water inlet; 104, water outlet; 200, gas distribution area; 201, convex strip; 202, boss; 300, ridge. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] See also Figure 1-2 As shown, the present invention is a graphite anode plate for PEMFC, including a plate body 100, the plate body 100 is rectangular as a whole, and a hydrogen inlet 101 and a hydrogen outlet 102 are respectively opened at the two end diagonals in the length extension direction of the plate body 100, and the hydrogen inlet 101 and the hydrogen outlet 102 are centrally symmetrical about the center point of the plate body 101; a flow field structure is arranged on the surface of the plate body 100, and the flow field structure is located between the hydrogen inlet 101 and the hydrogen outlet 102, and the air inlet of the flow field structure corresponds to the hydrogen inlet 101, and the air outlet corresponds to the hydrogen outlet 102.

[0027] A gas distribution area 200 is arranged between the hydrogen inlet 101 and the hydrogen outlet 102. The position distribution of the gas distribution area 200 between the hydrogen outlet 102 and the ridge channel 300 is the same as the position distribution of the gas distribution area 200 between the hydrogen inlet 101 and the ridge channel 300. Next, the position distribution of the gas distribution area 200 between the hydrogen outlet 102 and the ridge channel 300 is introduced.

[0028] The gas distribution area 200 is triangular in shape, and the hydrogen inlet 101 and the air inlet end of the flow field structure are respectively located on two adjacent sides of the triangle; the gas distribution area 200 includes a plurality of staggered convex strips 201 and bosses 202, the convex strips 201 are long strips, and the bosses 202 are cylindrical; wherein, the length extension direction of the convex strips 201 close to both the hydrogen inlet 101 and the flow field structure (area one) is perpendicular to the gas outlet direction of the hydrogen inlet 101, the length extension direction of the convex strips 201 close to the hydrogen inlet 101 but away from the flow field structure (area two) is perpendicular to the gas inlet direction of the flow field structure, and the length extension direction of the convex strips 201 away from the hydrogen inlet 101 but close to the flow field structure (area three) is parallel to the gas outlet direction of the hydrogen inlet 101.

[0029] When hydrogen enters the gas distribution area 200 from the hydrogen inlet 101, it first enters area one and area two. In area one, the flow direction of hydrogen is perpendicular to the length extension direction of the convex strip 201. Therefore, the convex strip 201 in area one can slow down the flow speed of hydrogen to the maximum extent and delay the time for hydrogen to enter the flow channel; in area two, the length extension direction of the convex strip 201 is toward area three, so the hydrogen can be guided in the direction of area three. After hydrogen enters area three from area two, the flow direction of hydrogen is parallel to the length direction of the convex strip 201 in area three. Therefore, the flow resistance of area three to hydrogen is very small, which can speed up the speed of hydrogen entering the flow channel. Based on this, the speed and flow rate of hydrogen in the hydrogen inlet 101 when entering the flow channel inlet can be synchronized to the greatest extent, ensuring that the movement speed of hydrogen in the ridge channel 300 tends to be stable as a whole, thereby improving the effect of the electrochemical reaction between hydrogen and the membrane electrode in the ridge channel 300.

[0030] The length of the convex strips 201 in the area three is shorter than that in the area one and the area two, which can further reduce the resistance of the convex strips 201 in the area three to hydrogen and speed up the speed at which hydrogen reaches the ridge channel 300 .

[0031] A plurality of hydrogen inlet gas distribution ports 1011 are provided between the hydrogen inlet 101 and the corresponding gas distribution area 200, and a plurality of corresponding hydrogen outlet gas distribution ports 1021 are provided between the hydrogen outlet 102 and the corresponding gas distribution area 200; the specific number of the hydrogen inlet gas distribution ports 1011 and the hydrogen outlet gas distribution ports 1021 is not limited. For example, in the present embodiment, four hydrogen inlet gas distribution ports 101 and four hydrogen outlet gas distribution ports 1021 are provided; taking the hydrogen inlet gas distribution ports 1011 as an example, after the hydrogen enters the hydrogen inlet 101, it enters the gas distribution area 200 through four hydrogen inlet gas distribution ports 1011, so that the hydrogen can be more evenly distributed.

[0032] See also Figure 3 The flow field structure includes a plurality of groups of ridges 300 arranged in parallel and equidistantly, and a flow channel is formed between two adjacent ridges 300. The ridges 300 are curved, and their widths change regularly. Therefore, the radial width of each flow channel changes regularly accordingly, which is conducive to the continuous conversion of the flow rate of hydrogen, thereby ensuring that the hydrogen is fully mixed and reacted with the fuel in the flow channel, improving the transmission efficiency of the hydrogen, and at the same time reducing the pressure drop in the flow channel and reducing the pressure loss when the fluid passes through the flow channel.

[0033] A plurality of water inlets 103 and water outlets 104 corresponding to the plurality of water inlets 103 are provided on the electrode body 100, wherein the plurality of water inlets 103 and the water outlets 104 are respectively arranged in parallel on both sides of the flow field structure, and are adjacent to the hydrogen inlet 101 and the hydrogen outlet 102; the number of the water inlets 103 and the water outlets 104 is not specifically limited. For example, in the present embodiment, four water inlets 103 and four water outlets 104 are both arranged, which are respectively located at the two ends of the ridge channel 300 in the width extension direction.

[0034] Cold water enters from the water inlet 103, passes through the side of the plate body 100 away from the ridge channel 300, and flows out from the water outlet 104. During this process, the cold water exchanges heat with the fluid in the ridge channel 300, which can cool the fluid and bring out the heat, which is beneficial to cooling the electrochemical reaction process and improving the performance and stability of the fuel cell.

[0035] Working principle of the present invention:

[0036] During gas distribution, hydrogen enters the gas distribution area 200 from the hydrogen inlet 101, and first enters area one and area two. In area one, the flow direction of hydrogen is perpendicular to the length extension direction of the ridge 201. Therefore, the ridge 201 in area one can slow down the flow speed of hydrogen to the maximum extent and delay the time for hydrogen to enter the ridge channel 300. In area two, the length extension direction of the ridge 201 is toward area three, so the hydrogen can be guided in the direction of area three. After the hydrogen enters area three from area two, the flow direction of hydrogen is parallel to the length direction of the ridge 201 in area three. Therefore, the flow resistance of area three to hydrogen is very small, which can speed up the speed of hydrogen entering the ridge channel 300. Based on this, the speed and flow rate of hydrogen in the hydrogen inlet 101 when entering the air inlet of the ridge channel 300 can be synchronized to the maximum extent, ensuring that the movement speed of hydrogen in the ridge channel 300 tends to be stable as a whole, thereby improving the effect of the electrochemical reaction between hydrogen and the membrane electrode in the ridge channel 300.

[0037] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying 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 direction and a specific direction structure and operation, and therefore, cannot be understood as a limitation on the present invention. In addition, "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the 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.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. 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 an indirect connection 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.

[0039] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A graphite anode plate for PEMFC, comprising a plate body (100), the plate body (100) being provided with a hydrogen inlet (101) and a hydrogen outlet (102) respectively located at two ends of the plate body (100), and a flow field structure located on one side of the plate body (100) being provided between the hydrogen inlet (101) and the hydrogen outlet (102); characterized in that: A gas distribution area (200) is provided between the hydrogen inlet (101) and the flow field structure, the gas distribution area (200) is in a triangular shape, and the hydrogen inlet (101) and the flow field structure are respectively located on two adjacent sides of the triangle; The gas distribution area (200) comprises a plurality of staggered convex strips (201) and bosses (202), wherein the length extension direction of the convex strips (201) close to the hydrogen inlet (101) and the flow field structure is perpendicular to the gas outlet direction of the hydrogen inlet (101), the length extension direction of the convex strips (201) close to the hydrogen inlet (101) but away from the flow field structure is perpendicular to the gas inlet direction of the flow field structure, and the length extension direction of the convex strips (201) away from the hydrogen inlet (101) but close to the flow field structure is parallel to the gas outlet direction of the hydrogen inlet (101).

2. The graphite anode plate for PEMFC according to claim 1, characterized in that: The length of the convex strip (201) far from the hydrogen inlet (101) but close to the flow field structure is shorter than the length of the convex strip (201) close to both the hydrogen inlet (101) and the flow field structure, and the length of the convex strip (201) close to the hydrogen inlet (101) but far from the flow field structure.

3. The graphite anode plate for PEMFC according to claim 1, characterized in that: A gas distribution area (200) is also provided between the hydrogen outlet (102) and the ridge channel (300), and the position distribution of the gas distribution area (200) between the hydrogen outlet (102) and the ridge channel (300) is the same as the position distribution of the gas distribution area (200) between the hydrogen inlet (101) and the ridge channel (300).

4. The graphite anode plate for PEMFC according to claim 3, characterized in that: A plurality of hydrogen inlet gas distribution ports (1011) are provided between the hydrogen inlet (101) and the corresponding gas distribution area (200), and a plurality of corresponding hydrogen outlet gas distribution ports (1021) are provided between the hydrogen outlet (102) and the corresponding gas distribution area (200).

5. The graphite anode plate for PEMFC according to claim 1, characterized in that: The flow field structure comprises a plurality of groups of ridges (300) arranged in parallel and equidistantly, and a flow channel is formed between two adjacent ridges (300).

6. The graphite anode plate for PEMFC according to claim 4, characterized in that: The ridge (300) is curved.

7. The graphite anode plate for PEMFC according to claim 4, characterized in that: The width of the ridge (300) varies regularly.

8. The graphite anode plate for PEMFC according to claim 1, characterized in that: A plurality of water inlets (103) and water outlets (104) corresponding to the plurality of water inlets (103) are provided on the electrode body (100), wherein the plurality of water inlets (103) and the water outlets (104) are arranged in parallel on two sides of the flow field structure adjacent to the hydrogen inlet (101) and the hydrogen outlet (102).

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