CN112687907B

CN112687907B - Polar plate and fuel cell

Info

Publication number: CN112687907B
Application number: CN201910989837.6A
Authority: CN
Inventors: 刘栋栋; 王鹏; 龚正伟; 韩亚民; 陶路鑫; 章宏文
Original assignee: Weishi Energy Technology Co Ltd
Current assignee: Weishi Energy Technology Co Ltd
Priority date: 2019-10-17
Filing date: 2019-10-17
Publication date: 2022-05-10
Anticipated expiration: 2039-10-17
Also published as: CN112687907A

Abstract

The invention provides a polar plate and a fuel cell, which relate to the technical field of fuel cells, and the polar plate comprises: a plate-shaped first body; the side surface of the first body facing the membrane electrode assembly is provided with a flow area for fluid to flow, the flow area is internally provided with at least one bulge, the at least one bulge divides the flow area into bent flow channels, and the cross section size of the flow channels at the upstream position in the flow direction of the fluid is larger than that of the flow channels at the downstream position in the flow direction of the fluid.

Description

Polar plate and fuel cell

Technical Field

The invention relates to the technical field of fuel cells, in particular to a polar plate and a fuel cell.

Background

A fuel cell is a device that directly converts chemical energy possessed by a fuel, which may be hydrogen gas, into electrical energy. Among them, the proton exchange membrane fuel cell is a fifth generation fuel cell developed after an alkaline fuel cell, a phosphoric acid type fuel cell, a molten carbonate fuel cell and a solid oxide fuel cell, and has the characteristics of low working temperature, short start-up time, high power density, fast load response, no electrolyte loss and the like.

The proton exchange membrane fuel cell comprises a plurality of single cells which are stacked, wherein each single cell comprises a membrane electrode assembly, a positive plate and a negative plate, and the positive plate and the negative plate are respectively attached to two sides of the membrane electrode assembly; the membrane electrode assembly comprises a proton exchange membrane, two catalyst layers and two diffusion layers, wherein one catalyst layer and one diffusion layer are sequentially stacked on one side of the proton exchange membrane, which is provided with a positive plate, and the other catalyst layer and the diffusion layer are sequentially stacked on one side of the proton exchange membrane, which is provided with a negative plate. One side of the anode plate close to the catalyst layer is provided with a flow channel for flowing hydrogen, and one side of the cathode plate close to the catalyst layer is provided with a flow channel for flowing air or oxygen. On the side of the anode plate (external circuit cathode), hydrogen gas is decomposed under the action of a catalyst to form hydrogen ions (namely protons) and electrons, the hydrogen ions move to the side of the anode plate (external circuit anode) through a proton exchange membrane, and the electrons move to the side of the anode plate along the external circuit to form current to supply power for a load; on the negative electrode plate side, oxygen gas is combined with electrons from an external circuit under the action of a catalyst to form oxygen ions, and then the oxygen ions react with hydrogen ions from the negative electrode of the external circuit to generate water. The flow channel structure of the prior plate is generally a serpentine or parallel flow channel, and fuel and air flow from the inlet to the outlet of the respective flow channel, and chemical reaction occurs during the flow.

However, the existing flow channel has low space utilization rate.

Disclosure of Invention

In view of the above problems, the present invention provides a polar plate and a fuel cell, which can improve the flow channel space utilization rate of the polar plate.

In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

a first aspect of the invention provides a plate comprising: a plate-shaped first body; the side of the first body facing the membrane electrode assembly is provided with a flow-through area for fluid to flow, the flow-through area is internally provided with at least one bulge, the bulge divides the flow-through area into bent flow channels, and the cross-sectional dimension of each flow channel at the upstream position along the flow direction of the fluid is larger than that at the downstream position along the flow direction of the fluid.

The pole plate as described above, wherein the cross-sectional dimensions of the convex portion at different positions in the extending direction thereof are all the same.

The plate as described above, wherein the at least one protrusion comprises: a first boss portion; the first end of the first bulge is connected with the edge of the circulation area, the second end of the first bulge is positioned in the circulation area, the first side of the first end of the first bulge corresponds to the inlet of the circulation area, and the second side of the first end of the first bulge corresponds to the outlet of the circulation area, so that the fluid flows in from the first side of the first end of the first bulge and flows out from the second side of the first end of the first bulge after bypassing the second end.

In the plate according to the above aspect, an extending direction of the first protrusion is inclined toward an inlet of the flow field so that the first protrusion is disposed at an acute angle with respect to an edge of the flow field.

The plate as described above, wherein a distance between the second end of the first projection and the inlet-side sidewall of the flow-through region is greater than or equal to a distance between the second end of the first projection and the outlet-side sidewall of the flow-through region.

The plate as claimed above, wherein the extending direction of the edge is perpendicular to the extending direction of the first protrusion, and the distance between the first protrusion and the inlet side sidewall of the flow-through region is greater than or equal to the distance between the first protrusion and the outlet side sidewall of the flow-through region.

The plate as described above, wherein the plate further comprises: the first turbulence part is laid in the circulation area, and the shape of the first turbulence part is matched with that of the circulation area; the first turbulence part is provided with a plurality of first turbulence areas arranged at intervals, and the height of each first turbulence area is lower than that of the end face of the first turbulence part.

The plate as described above, wherein each of the first spoiler regions has a length in the fluid flow direction that is greater than lengths in other directions.

The polar plate as described above, wherein the first turbulent flow regions are uniformly arranged on the first turbulent flow portion, so that the first turbulent flow portion is in a grid shape.

The plate as described above, wherein the plate further comprises: the second vortex portion that a plurality of interval was arranged, second vortex portion sets up on the first vortex portion, just second vortex portion is located adjacently between the first vortex region, second vortex portion with membrane electrode assembly offsets.

The pole plate as described above, wherein the length of the second spoiler portion along the fluid flowing direction is smaller than the lengths of the other directions.

The plate as described above, wherein the plate comprises: a third spoiler disposed within the flow area; and the third turbulence part is provided with a plurality of bulges or concave-convex structures, and the concave parts between the bulges or the concave parts of the concave-convex structures form a second turbulence area.

The electrode plate as described above, wherein the convex portion of the concavo-convex structure abuts against the membrane electrode assembly.

The plate as described above, wherein the plate comprises: the fourth vortex portion, fourth vortex portion includes the second body and forms runner in the second body, the runner supplies the fluid to pass, the runner communicates each other so that fourth vortex portion is porous netted.

Compared with the prior art, the polar plate provided by the embodiment of the invention has the following advantages: the fuel cell comprises a first body, wherein the first body is provided with a flow area for flowing of fluids such as hydrogen or oxygen, and the like; considering that the gas continuously reacts in the flowing process, the gas density at the downstream position of the flow channel is smaller than that at the upstream position of the flow channel, and the sectional dimension of the flow channel in the embodiment is adaptive and gradually reduced from the upstream position to the downstream position, so that the gas density can be maintained in a stable range, and the utilization rate of the flow area can be improved.

A second aspect of the present invention provides a fuel cell, comprising: at least one membrane electrode assembly and at least two polar plates as described above, said polar plates and said membrane electrode assemblies being arranged alternately; the membrane electrode assembly includes: proton exchange membrane, catalyst layer and diffusion layer; the number of the catalyst layers is two, and the catalyst layers are respectively attached to two side surfaces of the proton exchange membrane; the number of the diffusion layers is two, and the diffusion layers are respectively attached to the outer side surfaces of the two catalyst layers.

In addition to the technical problems solved by the embodiments of the present invention, the technical features constituting the technical solutions, and the advantages brought by the technical features of the technical solutions described above, other technical problems that the plate and the fuel cell provided by the embodiments of the present invention can solve, other technical features included in the technical solutions, and advantages brought by the technical features will be further described in detail in the detailed description.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a plate according to a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of another electrode plate according to the first embodiment of the present invention;

FIG. 3 is a second schematic diagram of the structure of the plate shown in FIG. 2;

FIG. 4 is a third schematic structural view of the plate of FIG. 2;

FIG. 5 is a first schematic structural diagram of the third spoiler portion;

FIG. 6 is a second schematic structural view of the third spoiler portion;

FIG. 7 is a schematic view of the principle of fluid perturbation;

fig. 8 is a schematic structural diagram of a fuel cell according to a second embodiment of the present invention.

Reference numerals:

10: a polar plate; 11: a first body; 12: a flow-through region;

20: a membrane electrode assembly; 21: a proton exchange membrane; 22: a catalytic layer; 23: a diffusion layer;

31: a first boss portion; 32: an inlet; 33: an outlet; 34: a first partitioning protrusion; 35: a second partitioning protrusion; 36: a third separation bulge; 37: a side projection;

40: a first spoiler portion; 41: a turbulent flow region; 42: a notch;

50: a second spoiler portion;

60: and a third spoiler portion.

Detailed Description

In order to make the aforementioned objects, features and advantages of the embodiments of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

When the proton exchange membrane fuel cell works, hydrogen and oxygen flow in the flow channels of the corresponding polar plates respectively, and the gas continuously reacts from the inlet end of the flow channel to the outlet end of the flow channel, so that the gas concentration is reduced at the position close to the outlet end of the flow channel, however, the cross section size of the existing flow channel is constant and inconvenient, and the utilization rate of the space of the flow channel close to the outlet end is low.

Example one

To solve the above problem, the present embodiment provides a polar plate, and fig. 1 is a schematic structural diagram of a polar plate according to an embodiment of the present invention; referring to fig. 1, a plate 10 includes: a plate-shaped first body 11; the side of the first body 11 facing the membrane electrode assembly 20 has a flow-through region 12 for fluid flow, the flow-through region 12 has at least one protrusion therein, the at least one protrusion divides the flow-through region 12 into bent flow channels, and the flow channels have a larger cross-sectional dimension at an upstream position in the flow direction of the fluid than at a downstream position in the flow direction of the fluid.

In particular, the plates are used in fuel cells to provide a flow field for the flow of fuel or oxygen. The fuel cell may include a plurality of unit cells stacked in sequence, each unit cell may include a membrane electrode assembly 20 and two electrode plates 10 disposed at two sides of the membrane electrode assembly 20, and a flow channel for fluid to flow is disposed at one side of each electrode plate 10 close to the membrane electrode assembly 20.

Each of the electrode plates 10 may include a first body 11, the first body 11 is supported between two adjacent membrane electrode assemblies 20, and in consideration of the electrical and thermal conductivity of the electrode plates 10, the material of the electrode plates 10 may be a carbon material, such as graphite, or a metal material, such as aluminum, nickel, titanium, etc., or a composite material, such as a mixture of a thermoplastic material, such as Polyethylene (PE), and graphite powder.

The first body 11 has a flow-through region 12 for fluid flow on one side or both sides adjacent to the membrane electrode assembly 20, and the flow-through region 12 may be a groove formed in a side surface of the first body 11, for example, the plate 10 may have a thickness of 3mm and a depth of 1.5 mm. When the first body 11 is made of a metal material, the flow area 12 may be formed by press molding using a press die.

The flow-through region 12 has at least one protrusion therein, and the at least one protrusion divides the flow-through region 12 into serpentine flow channels, which can increase the flow-through time of the fluid in the flow-through region 12 and increase the reaction rate of the fluid. In consideration of the fact that the gas density of the fluid at the outlet end is reduced, the sectional dimension of the flow channel is gradually reduced along the flow direction of the fluid, so that the gas density can be maintained in a stable range at any position of the flow channel. The depth of the flow channel may gradually decrease along the flow direction of the fluid, and optionally, in this embodiment, the depth of the fluid is constant along the flow direction of the fluid, and the width of the flow channel may gradually decrease along the flow direction of the fluid.

The protruding portion may be fixed to the first body 11 by welding or a locking pin, or may be formed integrally with the first body 11 by press molding. When the protrusion is integrally formed with the first body 11, specifically, the protrusion may further include a side protrusion 37 surrounding the flow area 12, the side protrusion 37 may be provided with an inlet 32 and an outlet 33 for fluid to flow in and out, and the protrusion is disposed between the inlet 32 and the outlet 33.

To increase the reaction rate of the gas, fig. 7 is a schematic diagram of a fluid disturbance principle, please refer to fig. 7, a turbulent flow groove for increasing the flow rate of the gas may be disposed in the flow region 12, when the gas flows through the turbulent flow groove, the gas flows along the groove surface of the turbulent flow groove to the side away from the membrane electrode and forms a turbulent flow, and then impacts the wall surface of the turbulent flow groove to accelerate the flow to the side of the membrane electrode assembly 20, thereby increasing the flow rate and activity of the gas, increasing the amount of gas capable of contacting the membrane electrode assembly 20, and preventing the gas from forming a laminar flow in the flow region 12, so that the gas at the side of the flow region 12 away from the membrane electrode assembly 20 does not contact the membrane electrode assembly 20.

The shape of the turbulence grooves may be circular, rectangular, rhombic, etc., the embodiment is not limited, and the number of the turbulence grooves may be one or more. The plurality of turbulent flow grooves can be irregularly distributed in the flow area, so that the irregularity of the gas flow is increased.

The plate 10 provided by the embodiment is provided with a flow area 12 for flowing fuel or oxygen, the flow area 12 is partitioned into a serpentine flow channel by at least one convex part, wherein the cross-sectional size of the flow channel is gradually reduced along the flow direction of the fluid so as to adapt to the situation that the gas density is gradually reduced at the downstream position of the flow channel, and the utilization rate of the flow channel space is improved.

Further, in order to improve the utilization rate of the plate space, each of the protrusions may have a constant cross-sectional size, that is, the cross-sectional sizes of the protrusions at different positions along the extending direction of the protrusions are the same.

It is understood that the area of the flow region 12 is the sum of the flow area and the area of the at least one protrusion, and the larger the flow area is, the larger the flow region 12 through which the gas can flow is, the larger the number of generated electrons is, that is, the larger the current density is, the larger the power density of the corresponding fuel cell is, wherein the power density is the quotient of the power of the fuel cell and the volume of the cell. Therefore, when the width of the flow channel in the present embodiment is gradually reduced along the flow direction of the fluid, the cross-sectional dimension of the protrusion may not change in the length direction thereof, and the width thereof may be 1mm to 2 mm. For the technical scheme that reduces runner cross sectional dimension through the mode of increase bellying cross sectional dimension, in the circulation region 12 of the same area, the area occupied by the bellying is littleer in this embodiment, and flow area is bigger, and current density is higher, and battery power density is bigger, and the high-usage of circulation region 12.

Further, the number of the protruding portions may be two or more, taking three as an example, please refer to fig. 1 continuously, the protruding portions may include a first separating protrusion 34, a second separating protrusion 35 and a third separating protrusion 36, the first separating protrusion 34, the second separating protrusion 35 and the third separating protrusion 36 are sequentially and respectively connected to two opposite sides of the flow area 12, and separate the flow area 12 into the serpentine flow channel, wherein the first separating protrusion 34 and the third separating protrusion 36 are located at the same side and may form an included angle with the side, and the second separating protrusion 35 is located at the opposite side and may be perpendicular to the corresponding side, so that the cross-sectional size of the flow channel may gradually decrease along the flow direction.

It can be understood that, the larger the number of the separating protrusions, the longer the length of the flow channel is, the more sufficient the gas reaction is, but the gas pressure in the flow channel may be reduced too much, alternatively, fig. 2 is a schematic structural diagram of another electrode plate provided in the first embodiment of the present invention, fig. 3 is a schematic structural diagram of the electrode plate in fig. 2, fig. 4 is a schematic structural diagram of the electrode plate in fig. 2, and please refer to fig. 2, fig. 3 and fig. 4, where at least one protrusion includes: the first boss portion 31; the first end of the first protrusion 31 is connected to the edge of the flow-through region 12, the second end of the first protrusion 31 is located in the flow-through region 12, the first side of the first end of the first protrusion 31 corresponds to the inlet 32 of the flow-through region 12, and the second side of the first end of the first protrusion 31 corresponds to the outlet 33 of the flow-through region 12, so that the fluid flows in from the first side of the first end of the first protrusion 31, bypasses the second end, and flows out from the second side of the first end of the first protrusion 31.

The number of the protruding portions in this embodiment may be one, and the protruding portions include the first protruding portion 31, one end of the first protruding portion 31 is connected to one side of the flow region 12, and the other end of the first protruding portion is directed to the other side opposite to the flow region 12, and divides the flow region 12 into U-shaped flow channels, and the length of the flow channel of the U-shaped flow channel is small, so that the gas can be sufficiently reflected, the gas pressure in the flow channel can be prevented from dropping too much, and the stability of the fuel cell can be maintained.

Further, the plate 10 provided by the embodiment includes only one first protruding portion 31, and is simple in structure and low in manufacturing cost.

In order to improve the space utilization of the plate 10, the extending direction of the first protrusion 31 is inclined toward the inlet 32 of the flow region 12 such that the first protrusion 31 is disposed at an acute angle with respect to the edge of the flow region 12.

Because the first protruding portion 31 and the side edge of the flow region 12 are arranged at an acute angle, the U-shaped flow channel is an asymmetric flow channel, and the requirement that the cross-sectional dimension of the flow channel gradually becomes smaller is met.

Further, referring to fig. 3, a distance between the second end of the first protrusion 31 and the sidewall of the inlet 32 side of the flow-through region 12 is greater than or equal to a distance between the second end of the first protrusion 31 and the sidewall of the outlet 33 side of the flow-through region 12. Wherein, the distance between the second end of the first projection 31 and the side wall on the inlet 32 side of the flow-through region 12 is greater than the distance between the second end of the first projection 31 and the corresponding side, and the distance between the second end of the first projection 31 and the corresponding side is greater than the distance between the second end of the first projection 31 and the side wall on the outlet 33 side of the flow-through region 12.

Alternatively, the extending direction of the edge may be perpendicular to the extending direction of the first protruding portion 31, and to realize the gradual decrease of the flow passage cross-sectional dimension along the fluid flowing direction, the first protruding portion 31 may be asymmetrically disposed in the flow-through region 12, specifically, the distance between the first protruding portion 31 and the side wall of the flow-through region 12 on the inlet 32 side is greater than or equal to the distance between the first protruding portion 31 and the side wall of the flow-through region 12 on the outlet 33 side.

Based on the above embodiment, with continued reference to fig. 2, 3 and 4, the plate 10 further includes: the first turbulence part 40 is laid in the circulation area 12, and the shape of the first turbulence part 40 is matched with that of the circulation area 12; the first spoiler portion 40 has a plurality of spoiler regions 41 arranged at intervals, and the height of the spoiler regions 41 is lower than the height of the end surface of the first spoiler portion 40.

In order to reduce the manufacturing costs, the first spoiler 40 may optionally be laid in the flow area 12 in the form of an integral plate, wherein the first spoiler 40 may have a strip-shaped recess 42 adapted to the projection.

The material of the first spoiler portion 40 may be the same as that of the pole plate 10, and the material may be a carbon material, such as graphite, or a metal material, such as aluminum, nickel, titanium, etc., or a composite material, such as a mixture of a thermoplastic material, such as Polyethylene (PE), etc., and graphite powder.

In order to disturb the gas, the first spoiler portion 40 may have a plurality of spoiler regions 41 thereon, and the spoiler regions 41 may be grooves or through holes formed on the first spoiler portion 40, that is, the depth of the spoiler region 41 may be less than or equal to the thickness of the first spoiler portion 40. The shape and distribution of the turbulent flow region 41 and the turbulent flow effect of the turbulent flow region 41 on the gas have been described in detail in the above embodiments, and are not described in detail in this embodiment. When the fuel cell supplies power to the load, when hydrogen and oxygen flow in the respective flow regions 12, the gas flowing into the groove may impact the side wall at the other end of the groove, so that the hydrogen and oxygen may impact the membrane electrode assembly 20 along the side wall of the groove, increasing the reaction amount of the hydrogen and oxygen, and increasing the current density.

Further, first vortex portion 40 can be fixed in the regional 12 that circulates through locking parts such as welding or screw, and split type structure, the equipment of being convenient for, and avoided the complicated stamping die of manufacturing and designing, it is with low costs. For example, when the first spoiler portion 40 is fixed in the spoiler region 41 by welding, the distance between two adjacent welding points may be 10mm to 20mm, which plays a role in fixing the first spoiler portion 40 and conducting electrons.

Further, in order to prevent the first spoiler 40 from forming an obstacle to the flow of the gas, the length of each spoiler region 41 in the fluid flow direction is greater than the lengths in the other directions.

Specifically, the length of the flow-through region 12 in the fluid flow direction is greater than the length of any other direction, so that the gas diffused in the flow direction is more than the gas diffused in other directions, the flow resistance of the gas in the flow direction is less than the flow resistance of the gas in other directions, so as to form the relative flow of the gas, and the flow guide effect on the gas can be formed by combining a plurality of flow-through regions 12.

For example, referring to fig. 3, the length of the flow-through regions 12 on the left and right sides of the first protrusion 31 in the vertical direction or along the length direction of the first protrusion 31 is greater than the length of the flow-through regions 12 on the lower side of the first protrusion 31 in any other direction.

The smoother the gas flow, the more new high-density gas can be supplied to the flow area 12 in time, and the gas reaction rate is improved.

The turbulent flow region 41 may be one or more of rectangular, rhombic, and elliptical, and the turbulent flow region 41 may be irregularly distributed in the flow region 12, and optionally, in order to reduce the manufacturing cost, the turbulent flow region 41 may be uniformly distributed on the first turbulent flow portion 40, so that the first turbulent flow portion 40 is in a grid shape.

Alternatively, the first spoiler portion 40 may be a metal mesh or a perforated metal plate in the prior art, and the spoiler region 41 may be each mesh of the metal mesh or the perforated metal plate, which is laid in the flow-through region 12, and is low in cost, easy to obtain, and convenient to process.

In order to reduce the gas flow resistance, the mesh openings can be rhombus, the length of the rhombus can be 0.5mm-4mm, the width of the rhombus can be 0.2mm-2mm, the gas flow resistance can be adjusted by adjusting the length-width ratio of the mesh openings of the rhombus, wherein the length-width ratio of the turbulent flow area 41 can be 2-8. Further, the wire diameter of the metal wires in the metal mesh may be 0.04mm to 0.2mm on the basis of being stably fixed in the flow-through region 12. Wherein, the wire diameter of the metal wire can be properly increased at the welding point, for example, 0.3mm-0.4mm, and the wire diameter of 0.04mm-0.2mm is selected in the non-welding area.

To optimize the turbulent effect, please continue to refer to fig. 2, 3 and 4, the plate 10 further includes: a plurality of second spoiler portions 50 arranged at intervals, the second spoiler portions 50 being disposed on the first spoiler portions 40, and the second spoiler portions 50 being located between adjacent spoiler regions 41, the second spoiler portions 50 abutting against the membrane electrode assembly 20. The second spoiler portions 50 may be a plurality of columnar protrusions formed on the first spoiler portion 40, and the plurality of spoiler columns may be uniformly distributed on the first spoiler portion 40, or irregularly distributed on the first spoiler portion 40. The cross-sectional shape of the spoiler column may be one or more of a circle, a rectangle, a diamond, etc., and this embodiment is not limited.

The columnar bulges can be mutually independent, and one end of each columnar bulge, which is deviated from the first turbulence part 40, is supported on the membrane electrode assembly 20, so that supporting points between the first body 11 of the polar plate 10 and the membrane electrode assembly 20 are increased, and the stability of the fuel cell is improved. The turbulence principle of the second turbulence portion 50 has been described in the above embodiments, and the description of this embodiment is omitted.

Further, the length of the second spoiler 50 in the fluid flow direction is smaller than the length in the other directions. Second vortex portion 50 can also produce the water conservancy diversion effect to gas when playing the effect to gas disturbance, and second vortex portion 50 is the same with the regional 41 water conservancy diversion effects to gas of vortex to the water conservancy diversion effect of gas, and this embodiment is no longer described any more.

As an embodiment of the spoiler, fig. 5 is a first structural schematic diagram of the third spoiler, fig. 6 is a second structural schematic diagram of the third spoiler, please refer to fig. 5 and fig. 6, and the plate includes: a third spoiler portion 60, the third spoiler portion 60 being disposed within the flow area; and the third spoiler portion 60 has a plurality of protrusions or concave-convex structures, and a second spoiler region is formed between concave portions between the protrusions or between concave portions of the concave-convex structures.

Specifically, the material of the third spoiler portion 60 may be the same as that of the pole plate 10, and the material may be a carbon material, such as graphite, or a metal material, such as aluminum, nickel, titanium, or a composite material, such as a mixture of a thermoplastic material, such as Polyethylene (PE), and graphite powder.

The third spoiler portion 60 may be a plurality of spoiler columns protruding from the flow region 12, and the plurality of spoiler columns may be uniformly distributed in the flow region 12 or irregularly distributed in the flow region 12. Wherein, the cross sectional shape of vortex post can be one or more of circular, rectangle, rhombus, irregular closed curve etc. and the cross sectional area of vortex post also can reduce gradually in its protruding direction, and this embodiment does not restrict.

Alternatively, the third spoiler 60 may also have a concave-convex structure, that is, the third spoiler 60 may be a plate shape having a non-planar geometric shape, and the third spoiler 60 may be fixed on the first plate body 11 by a fastener such as welding or pin. Illustratively, the concave-convex structure may be a continuous strip-shaped protrusion or recess, the number of which may be one or more, the strip-shaped protrusion or recess being directed from the inlet 32 to the outlet 33; the concave-convex structure may also be discontinuous convex portions or concave portions distributed on the third spoiler portion 60, and the convex portions or the concave portions may be uniformly distributed on the third spoiler portion 60 in an aligned manner, or may be irregularly distributed on the third spoiler portion 60.

When the fuel cell supplies power to the load, when hydrogen and oxygen flow in the respective flow regions 12, the hydrogen and oxygen may impact the protrusions or enter the recesses in the concave-convex structure at random and accelerate the impact of the protrusions, so that the hydrogen and oxygen may impact the mea 20 along the side surfaces of the protrusions or the protrusions, thereby increasing the reaction amount of the hydrogen and oxygen and increasing the current density.

It will be appreciated that the length of the recess in the direction of fluid flow may be greater than the length in the other directions.

Further, the protrusion deviates from one end of the third turbulence portion 60, or the end of the protrusion deviating from the third turbulence portion 60 in the concave-convex structure may have a gap with the membrane electrode assembly, so that gas flows, the contact area of the gas and the membrane electrode assembly is increased, and the current density is increased. Alternatively, the convex portion of the convex or concave-convex structure may abut against the membrane electrode assembly, increasing the supporting point between the electrode plate 10 and the membrane electrode assembly 20, and improving the stability of the fuel cell.

As another embodiment of the spoiler, the spoiler may be a mesh having a porous structure itself so that gas may pass through the inside of the spoiler, wherein the pole plate includes: the fourth vortex portion, fourth vortex portion include the second body and form the runner in the second body, and the runner supplies the fluid to pass, and the runner communicates each other so that fourth vortex portion is porous netted.

Specifically, the second body has flow-through ports at the inlet 32 and the outlet 33 through which the gas passes, and also has a flow-through port at a side of the second body adjacent to the membrane electrode assembly 20 so that the gas can contact the membrane electrode assembly 20. Illustratively, the second body may be supported between the first body 11 and the membrane electrode assembly 20 in a branched shape, and a side of the branched second body close to the membrane electrode assembly 20 may have a plurality of support points supported on the membrane electrode assembly 20.

Alternatively, the fourth spoiler may also be a plate shape having gaps inside, such as metal foam, graphite foam, or the like; it may also be in the form of a mesh which is itself porous, such as a metal mesh.

It can be understood that the spoiler on the first body 11 may be a combination of one or more of the first spoiler, the second spoiler, the third spoiler 60, and the fourth spoiler, and the embodiment is not limited.

Example two

Fig. 8 is a schematic structural diagram of a fuel cell according to a second embodiment of the present invention, please refer to fig. 8, which includes: at least one membrane electrode assembly and at least two polar plates as described in the previous embodiments, the polar plates and the membrane electrode assemblies being arranged alternately; the membrane electrode assembly includes: proton exchange membrane, catalyst layer and diffusion layer; the number of the catalyst layers is two, and the catalyst layers are respectively attached to two side surfaces of the proton exchange membrane; the number of the diffusion layers is two, and the diffusion layers are respectively attached to the outer side surfaces of the two catalyst layers.

Specifically, the fuel cell is capable of generating a voltage at both poles of the fuel cell to provide power to a load by a chemical reaction of hydrogen and oxygen. The fuel cell may include a plurality of unit cells stacked in sequence, each unit cell may include a membrane electrode assembly 20 and two electrode plates 10 disposed at two sides of the membrane electrode assembly, and a flow channel for fluid to flow is disposed at one side of each electrode plate 10 close to the membrane electrode assembly 20.

The membrane electrode assembly 20 may include: a proton exchange membrane 21, a catalyst layer 22, and a diffusion layer 23; the number of the catalyst layers 22 is two, and the catalyst layers are respectively attached to two side surfaces of the proton exchange membrane 21; the number of the diffusion layers 23 is two, and the diffusion layers are respectively bonded to the outer side surfaces of the two catalyst layers 22.

Among them, the Proton Exchange Membrane 21 (PEM) is a core component of a Fuel Cell (PEMFC), plays a key role in the performance of the Cell, and is used for conducting protons generated at one side of the positive plate.

The diffusion layer 23 includes a substrate layer, typically a porous carbon paper, carbon cloth, or the like, which may have a thickness of 100 μm to 400 μm, and a microporous layer, which serves to support the microporous layer and the catalytic layer 22. The microporous layer can be a carbon powder layer, the thickness of the microporous layer can be 10-100 μm, the void structure of the substrate layer can be improved, and the contact resistance between the catalytic layer 22 and the substrate layer can be reduced.

The material, structure, operation principle, etc. of the catalytic layer may be structures known to those skilled in the art, and this embodiment is not limited thereto.

The embodiments or implementation modes in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

In the description of the present specification, reference to the description of the terms "one embodiment", "some embodiments", "an illustrative embodiment", "an example", "a specific example", or "some examples", etc., means 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 invention. 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.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and these modifications or substitutions do not depart from the spirit of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A pole plate, comprising: the plate-shaped first body and the first turbulence part are arranged on the first flow channel;

the side of the first body facing the membrane electrode assembly is provided with a flow-through area for fluid to flow, the flow-through area is internally provided with at least one bulge, the at least one bulge divides the flow-through area into bent flow channels, and the cross-sectional dimension of each flow channel at the upstream position along the flow direction of the fluid is larger than that of the flow channel at the downstream position along the flow direction of the fluid;

the first turbulence part is laid in the circulation area, and the shape of the first turbulence part is matched with that of the circulation area;

the first turbulence part is provided with a plurality of first turbulence areas arranged at intervals, and the height of each first turbulence area is lower than that of the end face of the first turbulence part;

the height of the end face of the first turbulent flow portion is lower than that of the protruding portion.

2. The plate of claim 1, wherein the cross-sectional dimensions of the projections are the same at different locations along the extension of the projections.

3. The plate of claim 1, wherein the at least one boss comprises: a first boss portion;

the first end of the first bulge is connected with the edge of the circulation area, the second end of the first bulge is positioned in the circulation area, the first side of the first end of the first bulge corresponds to the inlet of the circulation area, and the second side of the first end of the first bulge corresponds to the outlet of the circulation area, so that the fluid flows in from the first side of the first end of the first bulge and flows out from the second side of the first end of the first bulge after bypassing the second end.

4. A plate according to claim 3, wherein the first projections extend in a direction inclined towards the inlet of the flow-through region such that the first projections are disposed at an acute angle to the edge of the flow-through region.

5. The plate of claim 3, wherein a distance between the second end of the first projection and an inlet side wall of the flow-through region is greater than or equal to a distance between the second end of the first projection and an outlet side wall of the flow-through region.

6. A plate as claimed in claim 3, wherein the edge extends in a direction perpendicular to the direction of extension of the first projection, and the distance between the first projection and the inlet side wall of the flow-through region is greater than or equal to the distance between the first projection and the outlet side wall of the flow-through region.

7. The plate of claim 1, wherein each of the first turbulator regions has a length in the direction of fluid flow that is greater than lengths in other directions.

8. The plate of claim 7, wherein the first turbulation regions are evenly arranged on the first turbulation portion such that the first turbulation portion is in a grid.

9. The plate of claim 1, further comprising: a plurality of second vortex portion of interval arrangement, second vortex portion sets up on the first vortex portion, just second vortex portion is located adjacently between the first vortex region, second vortex portion with membrane electrode assembly offsets.

10. The plate of claim 9, wherein the second turbulator has a length in the direction of fluid flow that is less than a length in the other directions.

11. The plate of any of claims 1-6, wherein the plate comprises: a third spoiler disposed within the flow area; the third turbulence part is provided with a plurality of bulges or concave-convex structures;

the concave portions between the protrusions or the concave portions of the concave-convex structure form a second turbulent flow region.

12. The plate of claim 11, wherein the convex portion of the relief structure abuts the membrane electrode assembly.

13. The plate of any of claims 1-6, wherein the plate comprises: the fourth vortex portion, fourth vortex portion includes the body and forms this internal runner, the runner supplies the fluid to pass, the runner communicates each other so that fourth vortex portion is porous netted.

14. A fuel cell, comprising: at least one membrane electrode assembly and at least two plates according to any one of claims 1 to 13, said plates and said membrane electrode assemblies being arranged alternately;

the membrane electrode assembly includes: proton exchange membrane, catalyst layer and diffusion layer; the number of the catalyst layers is two, and the catalyst layers are respectively attached to two side surfaces of the proton exchange membrane; the number of the diffusion layers is two, and the diffusion layers are respectively attached to the outer side surfaces of the two catalyst layers.