Visualizing the fuel cell device

Abstract

The present invention belongs to the field of fuel cells, and discloses a visualized fuel cell device, comprising: a cathode flow field unit, the cathode flow field unit is conductive; an MEA membrane electrode, the upper surface of the MEA is bonded to the bottom surface of the cathode flow field unit; and an anode flow field unit, the top surface of the anode flow field unit is bonded to the lower surface of the MEA, the anode flow field unit is conductive, at least one of the anode flow field unit and the cathode flow field unit is transparent, and the top surface of the anode flow field unit and the bottom surface of the cathode flow field unit are respectively grooved to form a flow channel, and a ridge is formed. The present invention sets at least one of the cathode flow field unit and the anode flow field unit to be transparent, so that the flow channel becomes a transparent flow channel, and then uses a high-speed camera equipped with a microscope lens to aim at the area to be photographed, so that the top or bottom and side of the flow channel can be visualized, thereby realizing the visualization of the flow state and distribution of the two-phase flow inside the fuel cell.

Description

Technical Field

[0001] The invention belongs to the technical field of fuel cells, and in particular relates to a visual fuel cell device. Background Art

[0002] Proton exchange membrane fuel cells have the advantages of low operating temperature, high efficiency, and environmental protection, and are an important member of future automotive power systems. However, the durability and performance of proton exchange membrane fuel cells are restricted by water management issues. Especially under high current density conditions, a large amount of water produced by the electrochemical reaction will be produced. If the water cannot be discharged quickly at this time, it will block the pores of the flow channel and the diffusion layer, causing the reaction gas to be unable to reach the reaction interface to react and the flow channel resistance to increase.

[0003] The fuel cell visualization device is a low-cost, intuitive device that can be used to study water management issues. The objects that can be studied include the distribution uniformity of the reaction gas in the flow channel, the observation of liquid water in the flow channel (flow pattern and its distribution), the distribution of liquid water on the surface of the diffusion layer, etc. Therefore, a wider range of visualization has always been a key requirement for such devices.

[0004] The Chinese patent application number: 201510919434.6, titled "A visualization device and method for flow field fluid distribution of a fuel cell bipolar plate", discloses a technical solution: combining a hollow flow channel with a transparent end plate to realize visualization of the top of the fuel cell flow channel, and using a high-speed resolution camera to capture the visualization phenomenon, but this invention cannot see the flow channel under the ridge, nor can it observe the side of the flow channel. The technical solution disclosed in the Chinese patent application number: 200710012312.4, titled "Bipolar plate flow field fluid visualization device and method", also has the same problem as above.

[0005] The Chinese patent application number is: 201810186909.9, and the invention name is a method for simulating gas distribution in a fuel cell device and its polar plate flow channel. A technical solution is disclosed: the flow channel is combined with a transparent cover or base plate, and a heavy ammonia solar paper is set between the flow channel and the transparent cover or base plate. During the implementation process, ammonia is added to the nitrogen, and the color change process is distinguished by the human eye or a high-speed camera to obtain the gas distribution. Obviously, this method can only be used to visualize the uniformity of the distribution of the reaction gas in the flow channel. Liquids such as water cannot be observed, and the ridge and the side of the flow channel cannot be seen. Summary of the invention

[0006] In order to at least solve the problem that the side of the flow channel cannot be visualized in the prior art, the present invention provides a visualized fuel cell device, which includes: a cathode flow field unit, which is conductive; an MEA membrane electrode, the upper surface of the MEA is bonded to the bottom surface of the cathode flow field unit; and an anode flow field unit, the top surface of the anode flow field unit is bonded to the lower surface of the MEA, the anode flow field plate is conductive, at least one of the anode flow field unit and the cathode flow field unit is transparent, and the top surface of the anode flow field unit and the bottom surface of the cathode flow field unit are respectively provided with grooves to form a flow channel and a ridge.

[0007] In the visualized fuel cell device as described above, preferably, the structure and size of the anode flow field unit are symmetrical with the structure and size of the cathode flow field unit about the plane where the MEA is located.

[0008] In the visualized fuel cell device as described above, preferably, the cathode flow field unit comprises: a first cathode flow field plate, the material of the first cathode flow field plate is a conductive transparent material, the bottom surface of the first cathode flow field plate is provided with the grooves to form the flow channel and the ridge.

[0009] In the visualized fuel cell device as described above, preferably, the cathode flow field unit includes: a second cathode flow field plate, the material of the second cathode flow field plate is a non-conductive transparent material, the bottom surface of the second cathode flow field plate is provided with the groove to form the flow channel and the ridge; and a first cathode collector plate, the material of the first cathode collector plate is a conductive transparent material, and there is a hollow portion, the size and position of the hollow portion are opposite to the groove, the top surface of the first cathode collector plate is in contact with the bottom surface of the second cathode flow field plate, and the bottom surface of the first cathode collector plate is in contact with the upper surface of the MEA.

[0010] In the visualized fuel cell device as described above, preferably, the cathode flow field unit includes: a second cathode flow field plate, the material of the second cathode flow field plate is a non-conductive transparent material, the bottom surface of the second cathode flow field plate is provided with the groove to form the flow channel and the ridge; and a second cathode collector plate, the material of the second cathode collector plate is a conductive material and is provided with a hollow portion, the hollow portion is opposite to the groove, the ridge passes through the hollow portion and is in contact with the upper surface of the MEA, and the size of the hollow portion is the size of the active area of ​​the visualized fuel cell device, the top surface of the second cathode collector plate is in contact with the bottom surface of the second cathode flow field plate, and the bottom surface of the second cathode collector plate is in contact with the upper surface of the MEA.

[0011] In the above-mentioned visualized fuel cell device, preferably, the second cathode flow field plate is made of transparent resin glass.

[0012] In the visualized fuel cell device as described above, preferably, when the material of the second cathode collector plate is a conductive non-transparent material, the second cathode collector plate is a gold-plated copper sheet.

[0013] In the visualized fuel cell device as described above, preferably, the visualized fuel cell device also includes: a cathode pressure plate and an anode pressure plate; the cathode pressure plate and the anode pressure plate are clamped on the top surface of the cathode flow field unit and the bottom surface of the anode flow field unit through connecting parts; a hollow hole is opened on each of the pressure plates at a position opposite to the groove to facilitate visualization.

[0014] In the visualized fuel cell device as described above, preferably, the visualized fuel cell device also includes: a cathode sealing ring and an anode sealing ring; the cathode sealing ring is arranged in a first annular groove opened on the bottom surface of the cathode flow field unit, and the first annular groove contains the groove of the cathode flow field unit; the anode sealing ring is arranged in a second annular groove opened on the top surface of the anode flow field unit, and the second annular groove contains the groove of the anode flow field unit.

[0015] In the above-mentioned visualized fuel cell device, preferably, the visualized fuel cell device further comprises: a high-speed camera equipped with a microscope lens, which is used to photograph the area to be visualized of the visualized fuel cell device to achieve visualization.

[0016] The technical solution provided by the embodiment of the present invention has the following beneficial effects:

[0017] 1) Simple processing and low cost;

[0018] 2) Visualization of the fuel cell flow channel and the MEA (especially the diffusion layer) surface under the ridges;

[0019] 3) Visualize the top and sides of the flow channel;

[0020] 4) Improve the force uniformity problem of the visualized fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of an explosion of a visualized fuel cell device provided by an embodiment of the present invention;

[0022] Figure 2 A schematic structural diagram of another visualized fuel cell device provided by an embodiment of the present invention;

[0023] Figure 3 A schematic structural diagram of another visualized fuel cell device provided by an embodiment of the present invention;

[0024] Figure 4A schematic structural diagram of another visualized fuel cell device provided in an embodiment of the present invention;

[0025] The symbols in the figure are explained as follows:

[0026] 1-MEA, 2-first cathode flow field plate, 3-second cathode flow field plate, 4-first cathode collector plate, 5-second cathode collector plate, 6-cathode pressure plate, 7-anode pressure plate, 8-cathode sealing ring, 9-anode sealing ring, 10-groove, 11-ridge, 12-hollow portion, 13-hollow portion, 14-bolt, 15-cathode flow channel inlet, 16-cathode flow channel outlet, 17-anode flow channel inlet, 18-anode flow channel outlet, 19-first anode flow field plate, 20-second anode flow field plate, 21-first anode collector plate, 22-second anode collector plate. DETAILED DESCRIPTION

[0027] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0028] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present invention and does not limit the present invention. In fact, it will be clear to those skilled in the art that modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature shown or described as a part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desired that the present invention encompasses such modifications and variations within the scope of the appended claims and their equivalents.

[0029] See also Figures 1 to 4 An embodiment of the present invention provides a visualized fuel cell device, which includes: a cathode flow field unit, a MEA1 (Membrane Electrode Assembly) and an anode flow field unit.

[0030] Specifically, the cathode flow field unit is conductive, and a groove 10 is opened on its bottom surface, and the groove 10 is used to form a flow channel, and the protrusion between adjacent grooves 10 is called a ridge 11. The structure of MEA1 is the same as the existing structure, and the present invention does not improve it. It can be a "three-in-one" component of electrode-membrane-electrode formed by hot pressing the anode, cathode and membrane together. The upper surface of MEA1 is bonded to the bottom surface of the cathode flow field unit, and the lower surface of MEA1 is bonded to the top surface of the anode flow field unit. The anode flow field unit is conductive, and a groove 10 is opened on its top surface, and the groove 10 is also used to form a flow channel, and the protrusion between adjacent grooves 10 is also called a ridge 11. The formation of the groove can be achieved by etching. A cathode flow channel inlet 15 and a cathode flow channel outlet 16 are provided on both sides of the cathode flow field unit. An anode flow channel inlet 17 and an anode flow channel outlet 18 are provided on both sides of the anode flow field unit. At least one of the anode flow field unit and the cathode flow field unit is transparent, that is, the anode flow field unit can be transparent, and the cathode flow field unit is a structure in the prior art and is opaque; the cathode flow field unit can also be transparent, and the anode flow field unit is a structure in the prior art and is opaque; and both the anode flow field unit and the cathode flow field unit can be transparent. By setting at least one of the cathode flow field unit and the anode flow field unit to be transparent, the flow channel of the process unit set to be transparent becomes a transparent flow channel, and then a high-speed camera equipped with a microscope lens is used to aim at the area to be photographed, that is, direct shooting, so that the top and side of the flow channel (relative to the cathode flow field unit) can be visualized and / or the bottom and side of the flow channel (relative to the anode flow field unit) can be visualized, thereby realizing the visualization of the flow state and distribution of the two-phase flow inside the fuel cell.

[0031] The structure and size of the anode flow field unit are symmetrical with the structure and size of the cathode flow field unit about the plane where the MEA is located. This facilitates the unified manufacturing of the anode flow field unit and the cathode flow field unit. In other implementations, the structures and sizes of the two may also be different, that is, they are not symmetrical about the plane where the MEA is located.

[0032] When the structures of the anode flow field unit and the cathode flow field unit are the same, the structure of the cathode flow field unit is used for explanation below. When describing the structure of the anode flow field unit, it is only necessary to replace "cathode" in the following components with "anode". For example, when the cathode flow field unit includes a first cathode flow field plate 2, correspondingly, the anode flow field unit includes: a first anode flow field plate 19; when the cathode flow field unit includes a second cathode flow field plate 3 and a first cathode collector plate 4, correspondingly, the anode flow field unit includes a second anode flow field plate 20 and a first anode collector plate 21; when the cathode flow field unit includes a second cathode flow field plate 3 and a second cathode collector plate 5, correspondingly, the anode flow field unit includes a second anode flow field plate 20 and a second anode collector plate 22.

[0033] See also Figure 2The cathode flow field unit may include: a first cathode flow field plate 2, which is made of a conductive transparent material, that is, the material is both conductive and transparent, so that the conductive cathode collector plate can be omitted. A groove 10 is opened on the bottom surface of the first cathode flow field plate 2 to form a flow channel, and a ridge 11 is formed. For the convenience of description, this solution can be called a solution without a collector plate.

[0034] In other embodiments, see Figure 3 , the cathode flow field unit may include: a second cathode flow field plate 3 and a first cathode collector plate 4. The material of the second cathode flow field plate 3 is a non-conductive transparent material, that is, its material is non-conductive and transparent, and the bottom surface of the second cathode flow field plate 3 is provided with a groove 10 to form a flow channel, and a ridge 11 is formed. Since the second cathode flow field plate 3 is a non-conductive material, a conductive cathode collector plate is required, that is, the first cathode collector plate 4 is a conductive transparent material, and is provided with a hollow portion 12. At this time, the first cathode collector plate 4 can be called a hollow collector plate, and the size and position of the hollow portion 12 are opposite to the groove 10, that is, the hollowed portion can just match the flow channel, the top surface of the first cathode collector plate 4 is in contact with the bottom surface of the second cathode flow field plate 3, and the bottom surface of the first cathode collector plate 4 is in contact with the upper surface of the MEA1, so that the contact area between the MEA1 and the first cathode collector plate 4 is large, so as to achieve the purpose of reducing impedance, and the structure is simple. For the convenience of description, this scheme can be called the first scheme with a collector plate.

[0035] In other embodiments, see Figure 4 , the cathode flow field unit may include: a second cathode flow field plate 3 and a second cathode collector plate 5. The second cathode flow field plate 3 is made of a non-conductive transparent material, and the bottom surface of the second cathode flow field plate 3 is provided with grooves 10 to form a flow channel, and a ridge 11 is formed. The second cathode collector plate 5 is made of a conductive material and has a hollow portion 13. At this time, the second cathode collector plate 5 can be called a hollow collector plate. The hollow portion 13 is opposite to all the grooves 10. The ridge 11 passes through the hollow portion 13 and fits the upper surface of the MEA1. The size of the hollow portion 13 is the size of the active area of ​​the visualized fuel cell device. The top surface of the second cathode collector plate 5 fits the bottom surface of the second cathode flow field plate 3, and the bottom surface of the second cathode collector plate 5 fits the upper surface of the MEA1. Since the ridge 11 passes through the hollow portion 13 and contacts the MEA1, it does not block the visualization under the ridge, and the simultaneous visualization of the ridge under the ridge and the flow channel can be achieved. Since the hollow portion 13 is provided, the material of the second cathode collector plate 5 can be a conductive transparent material or a conductive non-transparent material. In the application, a relatively large MEA 1 is used, and the outer periphery of the MEA 1 is in contact with the hollow collector plate to achieve electrical conduction. For the sake of ease of description, this solution can be referred to as the second solution with a collector plate.

[0036] In order to enhance the conductivity of the cathode collector plate, when the material of the second cathode collector plate 5 is a conductive non-transparent material, it is a gold-plated copper sheet. When the material of the second cathode collector plate 5 is a conductive transparent material, it is conductive glass. The material of the first cathode collector plate 4 can also be conductive glass. In order to improve the strength of the second cathode flow field plate 3, the material of the second cathode flow field plate 3 is transparent resin glass.

[0037] When the structures of the cathode flow field unit and the anode flow field unit are different, the structures of the cathode flow field unit and the anode flow field unit can be selected from two of the above three schemes, which can be: the cathode flow field unit selects the scheme without a collector plate, and the anode flow field unit selects the first scheme with a collector plate; it can also be: the cathode flow field unit selects the first scheme with a collector plate, and the anode flow field unit selects the second scheme with a collector plate; it can also be: the cathode flow field unit selects the second scheme with a collector plate, and the anode flow field unit selects the scheme without a collector plate; in other embodiments, it can also be a combination of other schemes, which is not limited in this embodiment.

[0038] Since the rigidity of transparent materials is relatively low, this will cause uneven force on the fuel cell and even cause gas leakage. A pressure plate is added outside the transparent material, that is, a cathode pressure plate 6 is added to the top surface of the cathode flow field unit, and an anode pressure plate 7 is added to the bottom surface of the anode flow field unit. Connectors, such as bolts 14, are passed through the anode pressure plate 7 and the cathode pressure plate 6 as well as the components between the two pressure plates to tighten and enhance the rigidity of the transparent material. The material of each pressure plate can be made of a material with high rigidity, such as steel. A hollow hole is opened on each pressure plate at a position opposite to the groove to avoid blocking the line of sight and hindering visualization.

[0039] In order to improve the sealing performance of the device, the device also includes: a cathode sealing ring 8 and an anode sealing ring 9. The cathode sealing ring 8 is arranged in a first annular groove opened on the bottom surface of the cathode flow field unit, and the first annular groove is the groove of the cathode flow field unit, that is, all the grooves of the cathode flow field unit are surrounded by the first annular groove. The anode sealing ring 9 is arranged in a second annular groove opened on the top surface of the anode flow field unit, and the second annular groove is the groove of the anode flow field unit, that is, all the grooves of the anode flow field unit are surrounded by the second annular groove. Specifically, taking the structure of the cathode flow field unit as an example, when the cathode flow field unit adopts a scheme without a collector plate, the first annular groove is arranged on the first cathode flow field plate 2; when the cathode flow field unit adopts the first scheme with a collector plate, the first annular groove is arranged on the first cathode collector plate 4; when the cathode flow field unit adopts the second scheme with a collector plate, the first annular groove is arranged on the second cathode collector plate 5.

[0040] It is known from common technical knowledge that the present invention can be implemented by other embodiments that do not deviate from its spirit or essential features. Therefore, the above disclosed embodiments are only illustrative in all respects and are not exclusive. All changes within the scope of the present invention or within the scope equivalent to the present invention are included in the present invention.

Claims

1. A visual fuel cell device, characterized in that: The visualized fuel cell device comprises: A cathode flow field unit, wherein the cathode flow field unit is conductive; MEA membrane electrode, the upper surface of the MEA is in contact with the bottom surface of the cathode flow field unit; and an anode flow field unit, wherein the top surface of the anode flow field unit is in contact with the lower surface of the MEA, and the anode flow field unit is conductive; At least one of the anode flow field unit and the cathode flow field unit is transparent, and grooves are respectively opened on the top surface of the anode flow field unit and the bottom surface of the cathode flow field unit to form flow channels and ridges; The structure and size of the anode flow field unit are symmetrical with the structure and size of the cathode flow field unit about the plane where the MEA is located; The cathode flow field unit comprises: a first cathode flow field plate, the material of the first cathode flow field plate is a conductive transparent material, and the cathode flow field unit does not contain a conductive cathode collector plate, and the bottom surface of the first cathode flow field plate is provided with the groove to form the flow channel and the ridge; or, The cathode flow field unit comprises: a second cathode flow field plate, wherein the second cathode flow field plate is made of a non-conductive transparent material, and the bottom surface of the second cathode flow field plate is provided with the grooves to form the flow channel and the ridge; and a first cathode collector plate, wherein the first cathode collector plate is made of a conductive transparent material and has a hollow portion, the size and position of the hollow portion are opposite to the groove, the top surface of the first cathode collector plate is in contact with the bottom surface of the second cathode flow field plate, and the bottom surface of the first cathode collector plate is in contact with the upper surface of the MEA; or The cathode flow field unit comprises: a second cathode flow field plate, wherein the second cathode flow field plate is made of a non-conductive transparent material, and the bottom surface of the second cathode flow field plate is provided with the grooves to form the flow channel and the ridge; and The second cathode collector plate is made of a conductive material and has a hollow portion, the hollow portion is opposite to the groove, the ridge passes through the hollow portion and is in contact with the upper surface of the MEA, and the size of the hollow portion is the size of the active area of ​​the visualized fuel cell device, the top surface of the second cathode collector plate is in contact with the bottom surface of the second cathode flow field plate, and the bottom surface of the second cathode collector plate is in contact with the upper surface of the MEA.

2. The visualized fuel cell device according to claim 1, characterized in that: The second cathode flow field plate is made of transparent resin glass.

3. The visualized fuel cell device according to claim 1, characterized in that: When the material of the second cathode collector plate is a conductive non-transparent material, the second cathode collector plate is a gold-plated copper sheet.

4. The visualized fuel cell device according to claim 1, characterized in that: The visualized fuel cell device further comprises: a cathode pressing plate and an anode pressing plate; The cathode pressure plate and the anode pressure plate are clamped and arranged on the top surface of the cathode flow field unit and the bottom surface of the anode flow field unit through a connecting piece; A hollow hole is provided on each of the pressing plates at a position opposite to the groove to facilitate visualization.

5. The visualized fuel cell device according to claim 1, characterized in that: The visualized fuel cell device further comprises: a cathode sealing ring and an anode sealing ring; The cathode sealing ring is arranged in a first annular groove opened on the bottom surface of the cathode flow field unit, and the first annular groove is the groove of the cathode flow field unit; The anode sealing ring is arranged in a second annular groove opened on the top surface of the anode flow field unit, and the groove of the anode flow field unit is inside the second annular groove.

6. The visualized fuel cell device according to claim 1, characterized in that: The visualized fuel cell device further comprises: a high-speed camera equipped with a microscope lens, which is used to photograph the area to be visualized of the visualized fuel cell device to achieve visualization.

Images