High-temperature fuel cell metal pole plate directly injected with water and processing method of high-temperature fuel cell metal pole plate

Abstract

The invention relates to a high-temperature fuel cell metal pole plate directly injected with water and a processing method thereof, the high-temperature fuel cell metal pole plate comprises a microchannel pole plate, a cathode plate and an anode plate, the upper and lower surfaces of the microchannel pole plate are provided with water distribution areas, water injection microchannels and microchannel pole plate ridges, and the microchannel pole plate ridges are provided with water injection ports. A polar plate runner is formed between every two adjacent micro-channel polar plate ridges, and cooling working medium water flows to the water injection port through the water distribution area and the water injection micro-channels and is injected into the polar plate runners; each of the cathode plate and the anode plate is provided with a gas distribution area, a gas distribution channel and a hollow gas flow channel which are sequentially communicated, and the cathode plate and the anode plate are respectively attached and fixed on the upper surface and the lower surface of the micro-channel polar plate, so that the corresponding gas flow channel is communicated with the polar plate flow channel. Compared with the prior art, humidity control is completed while high-heat-flux heat dissipation of the fuel cell is achieved.

Description

Technical Field

[0001] The present invention relates to the field of high-temperature fuel cell plate structures, and in particular to a high-temperature fuel cell metal plate directly injected with water and a processing method thereof. Background Art

[0002] At present, the high-temperature transformation of proton exchange membrane fuel cells (PEMFC) has become a research and development focus. By raising the operating temperature to the medium temperature range of 100-120°C (IT-PEMFC), the catalyst activity and gas diffusion efficiency can be significantly improved, and the power density can be increased by 15%-20%, while significantly reducing the use of precious metals and thermal management energy consumption. According to the U.S. Department of Energy (DOE) "Hydrogen Energy Technology Plan", the development of membrane electrode assemblies (MEAs) under 120°C operating conditions is the core research direction before 2030. Japan's NEDO has achieved thousand-hour-level stable operation verification of 110°C high-temperature reactors in the commercial vehicle field.

[0003] The industry urgently needs to break through the traditional plate cooling topology and focus on solving two major coupling contradictions: how to achieve self-regulating humidity management while maintaining high heat flux density heat dissipation; and how to reduce the volume of thermal management components through system integration innovation.

[0004] Japanese patent publication number JP2014504439A discloses a novel hybrid bipolar plate for fuel cells. Through a rationally designed gas flow field structure, cooling water is allowed to permeate through the top of the porous hydrophilic oxidant flow field plate and flow into the air flow path. As the cooling water flows downward along the oxidant flow path and evaporates, it removes heat and achieves a humidification effect. This solution achieves both heat dissipation and humidification through evaporative phase change by designing a novel plate structure. However, the high cost of using this novel structure hinders widespread application, and the cooling water is passively siphoned, making active regulation impossible.

[0005] Chinese patent publication number CN109065907A discloses a novel electrode plate with multiple water-retaining and water-discharging grooves alternately arranged on the flow channel ridges, interconnected with the flow channels. This plate can achieve humidification of the membrane electrode. While this electrode plate eliminates the need for a humidification device, it does not consider the use of the latent heat of vaporization of cooling water to achieve humidification at high heat flux densities. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a high-temperature fuel cell metal plate that is directly injected with water and a processing method thereof, which utilizes the latent heat of evaporation of water to achieve high heat flux density heat dissipation in the fuel cell while completing humidity control.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] A high-temperature fuel cell metal plate for direct water injection includes a microchannel plate, a cathode plate, and an anode plate. The upper and lower surfaces of the microchannel plate are provided with a water distribution area, a water injection microchannel, and a microchannel plate ridge. The microchannel plate ridge is provided with a water injection port. A plate flow channel is formed between two adjacent microchannel plate ridges. Cooling water flows through the water distribution area and the water injection microchannel to the water injection port and is injected into the plate flow channel.

[0009] The cathode plate and the anode plate are both provided with a gas distribution area, a gas distribution channel and a hollow gas flow channel. The gas distribution area, the gas distribution channel and the gas flow channel are connected in sequence. The cathode plate and the anode plate are respectively attached and fixed on the upper and lower surfaces of the microchannel electrode plate, so that the corresponding gas flow channels are connected with the electrode plate flow channels.

[0010] Furthermore, the microchannel plate, cathode plate and anode plate are positioned through positioning holes and fixed by sealant or welding.

[0011] Furthermore, the water distribution areas on the upper and lower surfaces of the microchannel plate are respectively located on both sides of the microchannel plate.

[0012] Furthermore, the two sides of the microchannel plate are provided with a first plate groove and a second plate groove of different widths for placing sealant or a sealing gasket.

[0013] Furthermore, the water distribution area, the water injection microchannels and the microchannel plate ridges on the microchannel plate are all formed by etching, and the wall of the water injection microchannel is a convex structure that is conducive to phase change.

[0014] Furthermore, the cathode plate has a centrally symmetrical structure, and an air distribution area, an air distribution channel and a hollow air flow channel are provided on one side of the cathode plate. The air distribution area is located at the entrance of the cathode plate, and the air in the air distribution area flows to the air flow channel through the air distribution channel and flows into the air plate flow channel on the upper surface of the microchannel plate.

[0015] Furthermore, the cathode plate has a first cathode groove and a second cathode groove with different widths on both sides for placing sealant or sealing gasket.

[0016] Furthermore, the anode plate has a centrally symmetrical structure, and a hydrogen distribution area, a hydrogen distribution channel and a hollow hydrogen flow channel are provided on one side of the anode plate. The hydrogen distribution area is located at the entrance of the anode plate, and the hydrogen in the hydrogen distribution area enters the hollow hydrogen flow channel through the hydrogen distribution channel and flows into the hydrogen electrode plate flow channel on the lower surface of the microchannel electrode plate.

[0017] Furthermore, the anode plate has a first anode groove and a second anode groove with different widths on both sides for placing sealant or sealing gasket.

[0018] The present invention also provides a method for processing a metal plate of a high-temperature fuel cell directly injected with water as described above, comprising the following steps:

[0019] The cathode plate, the anode plate and the microchannel plate without the water distribution area, the water injection microchannel and the water injection port are processed by a stamping or etching process;

[0020] Fabricate an electrolytic etching mask according to the requirements of the water distribution area, water injection microchannels, and water injection ports;

[0021] Based on the electrolytic etching mask, etching the water distribution area, the water injection microchannel and the water injection port on the surface of the microchannel plate by an electrolytic etching process;

[0022] Cleaning the etched microchannel plate;

[0023] The cathode plate, anode plate and microchannel plate are positioned through the positioning holes and fixed by sealant or welding to obtain the high-temperature fuel cell metal plate.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] (1) The present invention provides a water-injected microchannel plate and hollow cathode and anode plates, and supplies cooling water to the plate flow channels on the upper and lower surfaces through the water-injected microchannel plate; the hollow cathode and anode plates supply air and hydrogen respectively, and the gas flow channels are connected to the plate flow channels on the upper and lower surfaces of the water-injected microchannel plate through the hollow flow channel structure. In an environment greater than 100°C, the cooling water evaporates, and the phase change latent heat of water is utilized to achieve efficient heat dissipation of air and hydrogen. The evaporated gas is mixed with the air and hydrogen, and can achieve high heat flux density heat dissipation for the fuel cell while completing humidity control.

[0026] Even in an environment below 100°C, stable heat transfer can be achieved by increasing the flow rate of cooling water in the water-injected microchannel plates and utilizing the convection heat transfer characteristics.

[0027] (2) This invention is equivalent to directly injecting water into the gas flow path, utilizing the latent heat of water evaporation to achieve humidification and heat dissipation functions. Compared with existing high-temperature fuel cell structures, this technology does not require additional cooling water flow paths and humidification systems, significantly simplifying the system structure and reducing costs.

[0028] (3) The present invention utilizes a three-layer plate structure, combined with a hollow design and water-injection microchannels, to optimize the gas flow path and water injection efficiency. This design not only enables independent control of gas and cooling water, but also improves the compactness of the stack.

[0029] (4) In the processing method of the high-temperature fuel cell metal plate of the present invention, water injection microchannels are processed on the water injection microchannel plate through an electrolytic etching process, which has the characteristics of low processing cost and simple operation, and provides technical support for the commercial promotion of fuel cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the overall structure of a metal plate for a high-temperature fuel cell directly injected with water provided in an embodiment of the present invention;

[0031] Figure 2 A method provided in an embodiment of the present invention;

[0032] Figure 3 A schematic diagram of the overall structure of a microchannel plate provided in an embodiment of the present invention;

[0033] Figure 4 A schematic diagram of the detailed structure of a microchannel plate provided in an embodiment of the present invention;

[0034] Figure 5 A schematic diagram of a partial structure of a microchannel plate provided in an embodiment of the present invention;

[0035] Figure 6 A schematic diagram of the local structure of a microchannel plate in use according to an embodiment of the present invention;

[0036] Figure 7 A schematic diagram of the overall structure of a cathode plate provided in an embodiment of the present invention;

[0037] Figure 8 This is a schematic diagram of the front and back of a cathode plate provided in an embodiment of the present invention;

[0038] Figure 9 A schematic diagram of a partial structure of a cathode plate provided in an embodiment of the present invention;

[0039] Figure 10 A schematic diagram of the partial structure of a cathode plate in use according to an embodiment of the present invention;

[0040] Figure 11 This is a schematic diagram of the overall structure of an anode plate provided in an embodiment of the present invention;

[0041] Figure 12 This is a schematic diagram of the front and back of an anode and cathode plate provided in an embodiment of the present invention;

[0042] Figure 13 A schematic diagram of a partial structure of an anode plate provided in an embodiment of the present invention;

[0043] Figure 14A schematic diagram of the partial structure of an anode plate in use according to an embodiment of the present invention;

[0044] In the figure, 1. microchannel plate, 11. water distribution area, 12. water injection microchannel, 13. microchannel plate ridge, 14. water injection port, 18. first plate groove, 19. second plate groove, 2. cathode plate, 21. air distribution area, 22. air distribution channel, 23. air flow channel, 28. first cathode groove, 29. second cathode groove, 3. anode plate, 31. hydrogen distribution area, 32. hydrogen distribution channel, 33. hydrogen flow channel, 38. first anode groove, 39. second anode groove. DETAILED DESCRIPTION

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of 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. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0047] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0048] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the present invention.

[0049] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0050] Furthermore, terms such as "horizontal" and "vertical" do not necessarily mean that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0051] Example 1

[0052] like Figure 1 As shown, this embodiment provides a high-temperature fuel cell metal plate for direct water injection, including a microchannel plate 1, a cathode plate 2, and an anode plate 3. The upper and lower surfaces of the microchannel plate 1 are provided with a water distribution area 11, a water injection microchannel 12, and a microchannel plate ridge 13. A water injection port 14 is provided on the microchannel plate ridge 13. A plate flow channel is formed between two adjacent microchannel plate ridges 13. Cooling water flows through the water distribution area 11 and the water injection microchannel 12 to the water injection port 14 and is injected into the plate flow channel.

[0053] Both the cathode plate 2 and the anode plate 3 are provided with a gas distribution area, a gas distribution channel and a hollow gas flow channel. The gas distribution area, the gas distribution channel and the gas flow channel are connected in sequence. The cathode plate 2 and the anode plate 3 are respectively attached to the upper and lower surfaces of the microchannel electrode plate 1, so that the corresponding gas flow channels are connected with the electrode plate flow channels.

[0054] This solution provides a water-injected microchannel plate and hollow cathode and anode plates. The water-injected microchannel plate supplies cooling water to the plate flow channels on the upper and lower surfaces. The hollow cathode and anode plates supply air and hydrogen, respectively, and the gas flow channels are connected to the plate flow channels on the upper and lower surfaces of the water-injected microchannel plate through the hollow flow channel structure. In an environment greater than 100°C, the cooling water evaporates, utilizing the latent heat of water phase change to achieve efficient heat dissipation of air and hydrogen. The evaporated gas mixes with the air and hydrogen, achieving high heat flux density heat dissipation for the fuel cell while also achieving humidity control.

[0055] Even in an environment below 100°C, stable heat transfer can be achieved by increasing the flow rate of cooling water in the water-injected microchannel plates and utilizing the convection heat transfer characteristics.

[0056] Active control of heat dissipation and humidity can be achieved by controlling the liquid flow rate. The specific process is as follows:

[0057] At a fixed heat flux, evaporation can be controlled by precisely regulating the liquid flow rate. When humidification needs are high, the flow rate can be reduced to increase evaporation. When humidification needs are low, the flow rate can be increased to fully utilize convective heat transfer and reduce liquid phase changes.

[0058] like Figure 2 As shown in the figure, the metal plates and membrane electrode assembly (MEA) of a high-temperature fuel cell form the smallest repeating unit, which is used for the reaction between hydrogen and oxygen. By repeating this smallest unit, a fuel cell stack can be constructed.

[0059] Specifically, the microchannel plate 1 , the cathode plate 2 and the anode plate 3 are positioned through positioning holes and fixed by sealant or welding.

[0060] In this embodiment, positioning holes are respectively provided at the four corners of the microchannel plate 1 , the cathode plate 2 and the anode plate 3 for positioning.

[0061] For the microchannel plate 1 , only one water distribution area 11 is provided on a single side of the microchannel plate 1 , and the water distribution areas on the A side and the B side are on both sides of the microchannel plate 1 .

[0062] The water distribution area 11 is connected to the water injection microchannel 12, and the water injection microchannel flows to the water injection port 14 on the microchannel plate ridge 13

[0063] The A surface of the microchannel plate 1 is bonded to the D surface of the cathode plate 2, and the flow channel formed by the two plates is an air flow channel 15. The B surface of the microchannel plate 1 is connected to the F surface of the anode plate 3, and the flow channel formed by the two plates is a hydrogen flow channel 16.

[0064] The two sides of the microchannel plate 1 are provided with a first plate groove 18 and a second plate groove 19 of different widths for placing sealant or a sealing gasket.

[0065] Preferably, the water distribution area 11, the water injection microchannel 12 and the microchannel plate ridge 13 on the microchannel plate 1 are all obtained by etching. The water injection microchannel 12 is a non-smooth channel, and the channel wall has a tiny protrusion structure that helps phase change. The channel shape and width are not only straight as shown in the figure. The mask can be changed according to the heat dissipation requirements to obtain water injection microchannels of different shapes and sizes.

[0066] For the cathode plate 2, the cathode plate 2 is a centrally symmetrical structure, and an air distribution area 21, an air distribution channel 22 and a hollow air flow channel 23 are provided on one side of the cathode plate 2. The air distribution area 21 is located at the entrance of the cathode plate 2. The air in the air distribution area 21 flows to the air flow channel 23 through the air distribution channel 22 and flows into the air plate flow channel 15 between the two microchannel plate ridges 13 in the microchannel plate 1.

[0067] The cathode plate 2 has first cathode grooves 28 and second cathode grooves 29 of different widths on both sides for placing sealant or sealing gaskets.

[0068] As for the anode plate 3, the anode plate 3 has a centrally symmetrical structure. A hydrogen distribution area 31, a hydrogen distribution channel 32 and a hollow hydrogen flow channel 33 are provided on one side of the anode plate 3. The hydrogen distribution area 31 is located at the entrance of the anode plate 3. The hydrogen in the hydrogen distribution area 31 enters the hollow hydrogen flow channel 33 through the hydrogen distribution channel 32 and enters the hydrogen electrode plate flow channel 16 between the two microchannel electrode plate ridges 13 in the microchannel electrode plate 1.

[0069] The two sides of the anode plate 3 are provided with a first anode groove 38 and a second anode groove 39 of different widths for placing sealant or a sealing gasket.

[0070] This embodiment also provides a method for processing a high-temperature fuel cell metal plate directly injected with water, comprising the following steps:

[0071] S1: A cathode plate 2, an anode plate 3, and a microchannel plate 1 without a water distribution area 11, a water injection microchannel 12, and a water injection port 14 are processed by a stamping or etching process;

[0072] S2: making an electrolytic etching mask according to the requirements of the water distribution area 11, the water injection microchannel 12 and the water injection port 14;

[0073] S3: Based on the electrolytic etching mask, etching the water distribution area 11, the water injection microchannel 12 and the water injection port 14 on the surface of the microchannel plate 1 through an electrolytic etching process;

[0074] S4: cleaning the etched microchannel plate 1;

[0075] S5: Fix the cathode plate 2, the anode plate 3 and the microchannel plate 1 through the positioning holes by means of sealant or welding to obtain a high-temperature fuel cell metal plate with direct water injection in the reaction gas field.

[0076] The above describes in detail the preferred embodiments of the present invention. It should be understood that those skilled in the art can make numerous modifications and variations based on the concepts of the present invention without inventive effort. Therefore, any technical solutions that can be derived by those skilled in the art through logical analysis, reasoning, or limited experimentation based on the concepts of the present invention and the prior art should be within the scope of protection defined by the claims.

Claims

1. A high-temperature fuel cell metal plate directly injected with water, characterized in that: The invention comprises a microchannel plate (1), a cathode plate (2) and an anode plate (3); the upper and lower surfaces of the microchannel plate (1) are both provided with a water distribution area (11), a water injection microchannel (12) and a microchannel plate ridge (13); the microchannel plate ridge (13) is provided with a water injection port (14); a plate flow channel is formed between two adjacent microchannel plate ridges (13); cooling working medium water flows through the water distribution area (11) and the water injection microchannel (12) to the water injection port (14) and is injected into the plate flow channel; The cathode plate (2) and the anode plate (3) are both provided with a gas distribution area, a gas distribution channel and a hollowed-out gas flow channel, the gas distribution area, the gas distribution channel and the gas flow channel being connected in sequence, and the cathode plate (2) and the anode plate (3) are respectively fitted and fixed on the upper and lower surfaces of the microchannel electrode plate (1), so that the corresponding gas flow channels are connected to the electrode plate flow channels.

2. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The microchannel plate (1), cathode plate (2) and anode plate (3) are positioned through positioning holes and fixed by sealant or welding.

3. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The water distribution areas (11) on the upper and lower surfaces of the microchannel plate (1) are respectively located on both sides of the microchannel plate (1).

4. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The two sides of the microchannel plate (1) are provided with a first plate groove (18) and a second plate groove (19) of different widths for placing sealant or a sealing gasket.

5. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The water distribution area (11), water injection microchannel (12) and microchannel plate ridge (13) on the microchannel plate (1) are all formed by etching, and the wall of the water injection microchannel (12) has a convex structure that is conducive to phase change.

6. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The cathode plate (2) has a centrally symmetrical structure. An air distribution area (21), an air distribution channel (22), and a hollow air flow channel (23) are provided on one side of the cathode plate (2). The air distribution area (21) is located at the entrance of the cathode plate (2). The air in the air distribution area (21) flows to the air flow channel (23) through the air distribution channel (22) and flows into the air plate flow channel (15) on the upper surface of the microchannel plate (1).

7. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The cathode plate (2) has a first cathode groove (28) and a second cathode groove (29) with different widths on both sides, which are used for placing sealant or sealing gasket.

8. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The anode plate (3) has a centrally symmetrical structure. A hydrogen distribution area (31), a hydrogen distribution channel (32), and a hollow hydrogen flow channel (33) are provided on one side of the anode plate (3). The hydrogen distribution area (31) is located at the entrance of the anode plate (3). The hydrogen in the hydrogen distribution area (31) enters the hollow hydrogen flow channel (33) through the hydrogen distribution channel (32) and flows into the hydrogen plate flow channel (16) on the lower surface of the microchannel plate (1).

9. The metal plate for a high-temperature fuel cell for direct water injection according to claim 1, characterized in that: The two sides of the anode plate (3) are provided with a first anode groove (38) and a second anode groove (39) with different widths, which are used for placing sealant or sealing gasket.

10. A method for processing a metal plate of a high-temperature fuel cell for direct water injection according to any one of claims 1 to 9, characterized in that: The following steps are involved: A cathode plate (2), an anode plate (3), and a microchannel plate (1) without a water distribution area (11), a water injection microchannel (12), and a water injection port (14) are processed by a stamping or etching process; An electrolytic etching mask is produced according to the requirements of the water distribution area (11), the water injection microchannel (12) and the water injection port (14); Based on the electrolytic etching mask, etching a water distribution area (11), a water injection microchannel (12) and a water injection port (14) on the surface of the microchannel plate (1) through an electrolytic etching process; Cleaning the etched microchannel plate (1); The cathode plate (2), the anode plate (3) and the microchannel plate (1) are positioned through the positioning holes and fixed by sealant or welding to obtain a high-temperature fuel cell metal plate.

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