CN217955902U - Polar plate, bipolar plate, fuel cell and vehicle - Google Patents

Abstract

The application discloses a polar plate, a bipolar plate, a fuel cell and a vehicle. The plates of the embodiments of the present application are assembled to form bipolar plates for fuel cells. The polar plate comprises a sealing area and a reaction area. The sealing area is used for being attached to the frame membrane of the membrane electrode. The reaction zone is provided with at least two runner channels. A convex ridge is formed between the two runner grooves. The convex ridge is attached to the gas diffusion layer of the membrane electrode. The height of the ridge in the thickness direction of the plate is lower than the height of the sealing region in the thickness direction of the plate. In the process of stacking the polar plate and the membrane electrode, the gas diffusion layer of the membrane electrode is arranged in a protruding way relative to the frame membrane of the membrane electrode, so that the upper surface of the convex ridge can be attached to and compress the gas diffusion layer, and the gas diffusion layer forms permanent deformation, thus obtaining the gas diffusion layer with proper deformation.

Description

Polar plate, bipolar plate, fuel cell and vehicle

Technical Field

The present application relates to the field of fuel cell technology, and more particularly, to a polar plate, a bipolar plate, a fuel cell and a vehicle.

Background

In the related art, the fuel cell stack assembly usually adopts a stacking assembly method, and generally stacks the cells in series or stacks the cells after assembling the cells. The polar plate and the membrane electrode are important components in the fuel cell stack, and the membrane electrode comprises an anode catalyst layer, a proton exchange membrane, a cathode catalyst layer, two gas diffusion layers and two frame membranes.

During the process of stacking fuel cells, the stack needs to be compressed and loaded to ensure that the cathode plate, the anode plate, the gas diffusion layer and the catalyst layer have relatively low contact resistance, but the problem of inaccurate compression ratio of the gas diffusion layer is caused by the design incompatibilities of the electrode plates, so that the contact resistance is too high, or the gas diffusion layer excessively invades into the flow channel to influence the circulation of gas and water.

Therefore, there is a need for a plate that can achieve control of the compressibility of a gas diffusion layer.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a polar plate, a bipolar plate, a fuel cell and a vehicle.

The polar plate of this application embodiment is including sealing area and reaction zone, the sealing area be used for with the frame membrane laminating of membrane electrode, the reaction zone is provided with two at least runner grooves, two be formed with the convex ridge between the runner groove, the convex ridge is used for the laminating with the gas diffusion layer of membrane electrode, the convex ridge is followed highly being less than of polar plate thickness direction the sealing area is followed the height of polar plate thickness direction.

In the polar plate of this application embodiment, the height of edge polar plate thickness direction of convex ridge is less than the height of seal area edge polar plate thickness direction, the polar plate with membrane electrode pile in-process, the gaseous diffusion layer of membrane electrode is protruding to be set up for membrane electrode frame membrane is relatively outstanding for the convex ridge upper surface can laminate and compress gas diffusion layer, forms permanent deformation, can obtain the suitable gas diffusion layer of deformation volume.

In certain embodiments, the runner channel is linear or serpentine.

In certain embodiments, the runner channels are arranged in parallel.

In certain embodiments, the difference in height between the ridges and the sealing region is from 1 μm to 1000 μm.

In some embodiments, the ridges extend to a height of 10 μm to 1000 μm relative to the bottom of the flow channel grooves.

The bipolar plate of the embodiment of the present application includes an anode plate and a cathode plate which are attached to each other, the anode plate includes the plate of any one of the above embodiments, and/or the cathode plate includes the plate of any one of the above embodiments.

In some embodiments, a coolant flow channel is formed between the anode plate and the cathode plate.

A fuel cell of an embodiment of the present application includes a bipolar plate according to any one of the embodiments described above.

The vehicle of the embodiment of the present application includes a vehicle body and the fuel cell of the above embodiment, which is provided on the vehicle body.

In the polar plate, the bipolar plate, the fuel cell and the vehicle of the embodiment of the application, the height of the convex ridge is lower than that of the sealing area, and in the process of stacking the polar plate and the membrane electrode, the gas diffusion layer of the membrane electrode is arranged in a protruding mode relative to the membrane electrode, so that the upper surface of the convex ridge can be attached to and compress the gas diffusion layer to form permanent deformation, and the gas diffusion layer with the appropriate deformation can be obtained.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural view of a fuel cell of an embodiment of the present application;

FIG. 2 is a schematic cross-sectional view of a bipolar plate according to an embodiment of the present application;

FIG. 3 is a schematic cross-sectional structure of a plate according to an embodiment of the present application;

FIG. 4 is a schematic view of yet another cross-sectional configuration of a bipolar plate according to an embodiment of the present application; and

fig. 5 is a schematic structural diagram of a vehicle according to an embodiment of the present application.

Description of the main element symbols:

a polar plate 100,

The attaching surface 10, the reaction area 11, the runner groove 20, the raised ridge 30, the sealing area 40, the bipolar plate 200, the anode plate 201, the cathode plate 202, the coolant runner 203, the fuel cell 300, the vehicle 400 and the vehicle body 401.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative and are only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In this application, unless expressly stated or limited otherwise, the recitation of a first feature "on" or "under" a second feature may include the recitation of the first and second features being in direct contact, and may also include the recitation of the first and second features not being in direct contact, but being in contact with another feature between them. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. "beneath," "under" and "beneath" a first feature includes the first feature being directly beneath and obliquely beneath the second feature, or simply indicating that the first feature is at a lesser elevation than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the application. To simplify the disclosure of the present application, the components and settings of a specific example are described below. Of course, they are merely examples and are not intended to limit the present application. Moreover, the present application may repeat reference numerals and/or reference letters in the various examples, which have been repeated for purposes of brevity and clarity and do not in themselves dictate a relationship between the various embodiments and/or configurations discussed. In addition, examples of various specific processes and materials are provided herein, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.

Referring to fig. 1, a fuel cell 300 according to an embodiment of the present application includes a bipolar plate 200 according to an embodiment of the present application. Referring to fig. 2, a bipolar plate 200 according to an embodiment of the present disclosure includes an anode plate 201 and a cathode plate 202 opposite to each other, and the anode plate 201 and the cathode plate 202 include the plate 100 according to an embodiment of the present disclosure.

Referring to fig. 2 and 3, the plate 100 according to the embodiment of the present disclosure may be assembled to form a bipolar plate 200 of a fuel cell 300, where the plate 100 includes a sealing region 40 and a reaction region 11, the sealing region 40 is configured to be attached to a frame membrane of a membrane electrode, the reaction region 11 is provided with at least two flow channel grooves 20, a ridge 30 is formed between the two flow channel grooves 20, the ridge 30 is attached to a gas diffusion layer of the membrane electrode, and a height of the ridge 30 in a thickness direction of the plate 100 is lower than a height of the sealing region 40 in the thickness direction of the plate 100. The plate 100 further comprises an attachment surface 10, the attachment surface 10 being flush with the sealing area, i.e. the upper surface of the ridge 30 has a lower height than the attachment surface 10.

In the electrode plate 100 of the embodiment of the present application, the height of the raised ridge 30 in the thickness direction of the electrode plate 100 is lower than the height of the attachment surface 10 in the thickness direction of the electrode plate 100, that is, the height of the upper surface of the raised ridge 30 is lower than the height of the attachment surface 10 and the sealing area 40, and in the stacking process of the electrode plate 100 and the membrane electrode, the gas diffusion layer of the membrane electrode is protruded relative to the membrane electrode, so that the upper surface of the raised ridge 30 can be attached and compress the gas diffusion layer, and the gas diffusion layer forms permanent deformation, i.e., a gas diffusion layer with an appropriate deformation amount can be obtained.

Specifically, the fuel cell 300 can directly convert chemical energy into electrical energy, thereby realizing chemical power generation with less pollution. In the embodiment of the present application, the fuel cell 300 may be a hydrogen fuel cell, which can convert chemical energy in hydrogen and oxygen into electrical energy, and the accompanying product is only water, so that the whole power generation process does not generate harmful substances, and has no pollution to the environment. It should be noted that the plate 100 of the present application may be first positioned on the attachment surface 10, and then the ridges 30 and the runner grooves 20 are obtained by etching. In addition, the specific number of runner channels 20 is not limited in this application to meet various requirements.

Further, the fuel cell 300 is formed by stacking a plurality of proton exchange membrane single cells, and each proton exchange membrane single cell includes a bipolar plate 200 and a membrane electrode, wherein the membrane electrode is formed by laminating a cathode gas diffusion layer, a cathode catalyst layer, a proton exchange membrane, an anode catalyst layer and an anode gas diffusion layer into a whole and is in a sheet shape. The two bipolar plates 200 are attached to two opposite sides of the membrane electrode, so that the anode plate 201 can be attached to the anode gas diffusion layer correspondingly, and the cathode plate 202 is attached to the cathode gas diffusion layer correspondingly, so that a plurality of membrane electrodes and the bipolar plates 200 are repeatedly attached in sequence, that is, the membrane electrodes, the bipolar plates 200, the membrane electrodes and the bipolar plates 200 can be repeatedly attached to the bipolar plates 200 in sequence, and the membrane electrodes can be matched with the adjacent anode plate 201 and the adjacent cathode plate 202 to form a complete power generation unit. In some embodiments, an anode plate 201 and a cathode plate 202 are attached to the upper and lower sides of the membrane electrode to form a power generation unit, i.e., a single cell, and a plurality of power generation units are stacked together to form a complete fuel cell 300. In other embodiments, the anode plate 201 and the cathode plate 202 are attached to form the bipolar plate 200, such that the channel 20 and the raised ridge 30 face outward, and the bipolar plate 200 and the membrane electrode are stacked together in sequence to form a complete fuel cell 300.

It can be understood that, in the process of attaching the membrane electrode to the bipolar plate 200, a plurality of single proton exchange membrane cells need to be stacked, and in this process, if the compression ratio of the gas diffusion layer is not accurate due to improper stacking force applied, the contact resistance is too high, or the gas diffusion layer excessively invades into the flow channel groove 20 to block the gas inlet and outlet and the flow channel groove 20, the reaction gas is not smoothly circulated and the generated water is not smoothly discharged. And in this application, the height of convex ridge 30 along polar plate 100 thickness direction is less than the height of attached face 10 along polar plate 100 thickness direction, and gas diffusion layer is after laminating with convex ridge 30 upper surface, makes gas diffusion layer's compressive capacity suitable, and the compressibility of quantitative control gas diffusion layer can be isolated with different runner grooves 20, avoids gas diffusion layer excessively to stretch into runner groove 20 simultaneously and blocks up runner groove 20.

In the embodiment of the present application, the material of the electrode plate 100 is not limited, and the electrode plate 100 may be made of graphite, metal, or the like to meet various requirements. In addition, the flow channel groove 20 of the plate 100 may be formed by etching or punching, and a coating process may be performed on the surface of the plate 100 to change the properties of the plate 100. In some embodiments, a titanium metal coating may be sprayed on the surface of the electrode plate 100, and the titanium metal has the advantages of corrosion resistance, low density, and the like, and is helpful for improving the performance, the service life, and the reliability of the fuel cell 300. The two pole plates 100 can be attached to each other in a back-to-back manner, so that the runner groove 20 faces outward, and the two pole plates 100 can be connected together in a welding manner, thereby ensuring stable connection.

It should be noted that, the edge portion of the ridge 30 is formed with a chamfer or a fillet, so as to avoid the problem that the ridge 30 scratches on the gas diffusion layer when the ridge 30 is attached to the gas diffusion layer.

When the fuel cell 300 according to the embodiment of the present invention is a hydrogen fuel cell, hydrogen and oxygen are supplied to the flow channel 20 of the anode plate 201 and the flow channel 20 of the cathode plate 202, respectively, and after the hydrogen diffuses out through the flow channel 20 of the anode plate 201 and reacts with an electrolyte, electrons are emitted to the cathode plate 202 through an external load, and at the same time, the hydrogen gas emits electrons and becomes protons, which may enter the flow channel 20 of the adjacent cathode plate 202 through a proton exchange membrane and combine with oxygen ions that have obtained the electrons to generate water. That is, the flow channel 20 of the anode plate 201 may be circulated with hydrogen gas, and the flow channel 20 of the cathode plate 202 may be circulated with air containing oxygen gas and generated water.

Referring to fig. 1 and 2, in some embodiments, the runner channel 20 is linear or serpentine. Thus, the linear flow channel 20 has a simple structure, so that hydrogen and oxygen can rapidly pass through the flow channel 20, thereby preventing the flow channel 20 from being blocked. When the runner channel 20 is provided with the serpentine type or the serpentine shape, the contact area between the gas and the runner channel 20 and the membrane electrode can be increased, so that the effective reaction area is larger, the accumulated water area is small, and the reaction efficiency can be improved.

Further, referring to fig. 1 and 2, in some embodiments, the runner channels 20 are arranged in parallel. So, a plurality of runner groove 20 parallel arrangement for hydrogen and oxygen can be passed through along a plurality of runner groove 20 are parallel, and different runner grooves 20 can react simultaneously, have increased the area of contact of gas with the runner plate, and then have promoted the chemical reaction effect.

Specifically, in such an embodiment, the straight runner duct 20 may rapidly communicate the gas inlet and the gas outlet, so that hydrogen and oxygen may smoothly pass through, and rapid reaction may be ensured.

In the present embodiment, the shape of the runner duct 20 and the size and shape of the cross-sectional area are not limited to meet various requirements. Of course, in some embodiments, the runner duct 20 may also have other shapes such as a curve, a broken line, or an arc, so that the flow direction of the gas changes along with the runner duct 20 to change the reaction speed of the reaction gas. In some embodiments, the cross-sectional area of the flow channel 20 may vary, and the cross-sectional area of the flow channel 20 may be rectangular, trapezoidal, or the like.

Referring to fig. 2 and 3, in some embodiments, the height difference between the ridge 30 and the sealing region 40 is 1 μm to 1000 μm. For example, the difference in height between the ridge 30 and the sealing zone 40 may be 1 μm, 2 μm, 3 μm, 5 μm, 10 μm, 20 μm, 50 μm, 100 μm, 500 μm, 1000 μm, etc. So, at this distance within range, gas diffusion layer stretches into polar plate 100 and the laminating of convex ridge 30 is in the same place, and the runner groove 20 that will differ is isolated to have better sealed effect, avoids gas diffusion layer excessively to invade runner groove 20 simultaneously and blocks up air inlet and gas outlet and runner groove 20, guarantees that the circulation of reaction gas and formation water is smooth and easy.

Specifically, the difference in height between the ridges 30 and the sealing area 40 may be any value from 1 μm to 1000 μm, so that the compressibility of the gas diffusion layer may be in a suitable range. Illustratively, the distance between the ridges 30 and the attachment surface 10 may be 100 μm, and the gas diffusion layer may protrude from the membrane electrode such that the gas diffusion layer may abut against the upper surfaces of the ridges 30 and separate the different flow channel grooves 20.

Referring to fig. 2 and 3, in some embodiments, a sealing region 40 is formed at the periphery of the runner groove 20, and the upper surface of the sealing region 40 coincides with the attachment surface 10.

Like this, sealing area 40 and attached surface 10 coincide for sealing area 40 can assemble with the membrane electrode cooperation, simultaneously because sealing area 40 and attached surface 10 coincide, the upper surface of sealing area 40 is higher than the upper surface of ridge 30, makes sealing area 40 and membrane electrode complex while ridge 30 can form a plurality of runner grooves 20 with the cooperation of gas diffusion layer.

Further, referring to fig. 2 and 3, in some embodiments, the protruding height of the ridge 30 relative to the bottom of the runner groove 20 is 10 μm to 10000 μm. For example, the protruding heights of the ridges 30 with respect to the bottom of the flow channel groove 20 may be 10 μm, 20 μm, 50 μm, 100 μm, 500 μm, 1000 μm, and 10000 μm. So, the convex ridge 30 is in this height range, makes gas diffusion layer laminate with convex ridge 30 upper surface, and gas diffusion layer's compressive capacity is suitable, and the compressibility of quantitative control gas diffusion layer can be isolated with different runner channels 20, avoids gas diffusion layer too to stretch into runner channel 20 simultaneously and blocks up runner channel 20.

In particular, it will be appreciated that the sealing region 40 coincides with the attachment surface 10 and the upper surface of the ridge 30 is lower than the upper surface of the sealing region 40, i.e. the upper surface of the sealing region 40 may serve as a site for attachment to the membrane electrode from which a gas diffusion layer may extend over the attachment surface 10 and into contact with the upper surface of the ridge 30, being held in compression by the upper surface of the ridge 30.

Illustratively, the protruding height of the ridge 30 relative to the bottom of the runner channel 20 may be any value from 10 μm to 10000 μm, although the height of the upper surface of the ridge 30 needs to match the height of the sealing area 40, thereby defining the distance between the ridge 30 and the attachment surface 10 and the sealing area 40. In one example, the protruding height of the ridge 30 with respect to the bottom of the channel 20 may be 1000 μm, and the distance between the ridge 30 and the sealing region 40 may be 100 μm, in which case the protruding height of the sealing region 40 with respect to the bottom of the channel 20 is 1100 μm.

Referring to fig. 4, in some embodiments, a coolant flow channel 203 is formed between the anode plate 201 and the cathode plate 202. In this way, the coolant flow channel 203 can circulate the coolant to cool the bipolar plate 200, and the heat generated by the oxygen reduction reaction is taken out through the coolant, thereby ensuring that the reaction in the flow channel groove 20 can be performed at a proper temperature.

Referring to fig. 5, a vehicle 400 according to an embodiment of the present application includes a vehicle body 401 and the fuel cell 300 according to the above embodiment, and the fuel cell 300 is provided on the vehicle body 401.

In the polar plate 100, the bipolar plate 200, the fuel cell 300, and the vehicle 400 according to the embodiment of the present application, the height of the raised ridge 30 is lower than the height of the attachment surface 10, and in the process of stacking the polar plate 100 with the membrane electrode, the gas diffusion layer of the membrane electrode protrudes relative to the membrane electrode, so that the upper surface of the raised ridge 30 can be attached to and compress the gas diffusion layer to form permanent deformation, and thus the gas diffusion layer with a proper deformation amount can be obtained.

In the embodiment of the present invention, the type of the vehicle 400 is not limited, and the vehicle 400 may be an electric vehicle or a hybrid vehicle, and only the vehicle body 401 needs to be provided with the fuel cell 300 of the present invention, so as to satisfy various requirements.

In the description of the embodiments of the present application, the terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

In the description herein, references to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present application have been shown and described above, it is to be understood that the above embodiments are exemplary and not to be construed as limiting the present application, and that changes, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present application.

Claims (9)

1. The polar plate is characterized by comprising a sealing area and a reaction area, wherein the sealing area is used for being attached to a frame membrane of a membrane electrode, the reaction area is provided with at least two flow channel grooves, a raised ridge is formed between the two flow channel grooves and used for being attached to a gas diffusion layer of the membrane electrode, and the height of the raised ridge in the thickness direction of the polar plate is lower than that of the sealing area in the thickness direction of the polar plate.

2. The plate of claim 1, wherein the flow channel groove is linear or serpentine.

3. The plate of claim 2 wherein said runner channels are arranged in parallel.

4. The plate of claim 1, wherein the ridges have a height differential from the sealing region of 1 μm to 1000 μm.

5. The plate of claim 1 wherein said ridges extend from 10 μm to 1000 μm in height relative to the bottom of said flow channel slots.

6. A bipolar plate, comprising an anode plate and a cathode plate which are arranged opposite to each other, wherein the anode plate is the plate of any one of claims 1 to 5, and/or the cathode plate is the plate of any one of claims 1 to 5.

7. The bipolar plate of claim 6 wherein a coolant flow channel is formed between the anode plate and the cathode plate.

8. A fuel cell comprising a bipolar plate according to any one of claims 6 to 7.

9. A vehicle characterized by comprising a vehicle body and the fuel cell according to claim 8, the fuel cell being provided on the vehicle body.

Images