CN114023988A

CN114023988A - Fuel cell plate and cell unit

Info

Publication number: CN114023988A
Application number: CN202111293386.6A
Authority: CN
Inventors: 陆濛洲; 张义煌; 易沙; 陈杰; 李刚; 吴楚
Original assignee: Wuxi Weifu High Technology Group Co Ltd
Current assignee: Wuxi Weifu High Technology Group Co Ltd
Priority date: 2021-11-03
Filing date: 2021-11-03
Publication date: 2022-02-08
Anticipated expiration: 2041-11-03

Abstract

The application discloses fuel cell polar plate, including the base plate, the base plate has first face and second face, carries out the punching press to first face, forms the circulation passageway of sinking towards the second face on the first face to form on the second face and keep away from the bellied protruding spine of first face, form the circulation passageway between two arbitrary adjacent protruding spines on the second face, the circulation passageway constitutes the flow field area, from this, all has the flow field area on first face and the second face. The fuel cell polar plate provided by the application can be used as a cathode plate, an anode plate and a bipolar plate, has a simple structure and is reliable to use. The application also discloses a battery unit, which comprises two fuel battery pole plates, a cathode side gas diffusion layer and an anode side gas diffusion layer; a cathode-side gas diffusion layer and an anode-side gas diffusion layer are disposed between the two fuel cell plates. By assembling a plurality of cell units, a fuel cell stack can be quickly constructed.

Description

Fuel cell plate and cell unit

Technical Field

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

Background

The polar plate is used as a core component in the fuel cell, not only has the functions of collecting current and supporting a membrane electrode, but also can distribute reaction gas.

The existing polar plate has complex design and large processing difficulty. Especially, the bipolar plate has different structures of the cathode plate and the anode plate, and needs to be provided with a plurality of moulds, so that the development and manufacturing period is increased, and the research and development cost is increased.

Disclosure of Invention

The present application is directed to overcome the deficiencies in the prior art and to provide a fuel cell plate and a battery unit.

In order to achieve the above technical object, the present application provides a fuel cell plate, including a substrate having a first surface and a second surface, the first surface and the second surface being opposite to each other; stamping the first surface, forming a flow channel which is concave towards the second surface on the first surface, and forming a convex ridge which is convex away from the first surface on the second surface; a flow channel is formed between any two adjacent raised ridges on the second surface; the flow channel forms a flow field region for guiding the flow of the reaction gas; the first side and the second side each have a flow field region thereon.

Furthermore, any flow channel extends along the first direction, and a plurality of flow channels are arranged at intervals along the second direction; the first direction is perpendicular to the second direction.

Further, the substrate is provided with: the first inlet is arranged on a first side of the flow field area along a first direction; the first outlet is arranged at the second side of the flow field area along the first direction; when the fuel cell polar plate is used as a polar plate of the first reaction gas, the first reaction gas can enter the flow field area through the first inlet, and the first reaction gas can be discharged through the first outlet by being guided by the flow field area; the first second inlet is arranged on the third side of the flow field area; the second inlet is arranged on the second side of the flow field area along the first direction; the second outlet is arranged on the first side of the flow field area along the first direction; when the fuel cell polar plate is used as a polar plate of the second reaction gas, the second reaction gas can enter the second inlet through the first second inlet, then enter the flow field region through the second inlet, and can be discharged through the second outlet by being guided by the flow field region.

Further, at least a portion of the first outlet is below the flow field region; and/or at least a portion of the second outlet is below the flow field region.

Further, the first outlet and/or the second outlet are/is communicated with the first second inlet through a pipeline; the water discharged through the first outlet or the second outlet acts on the second reaction gas in the first second inlet through a pipeline.

Furthermore, a third inlet and a third outlet are also arranged on the substrate; one of the third inlet and the third outlet is arranged on the first side of the flow field area, and the other of the third inlet and the third outlet is arranged on the second side of the flow field area; coolant can enter the flow field region through a third inlet and can be discharged through a third outlet.

Furthermore, the substrate is also provided with a positioning hole.

Furthermore, a voltage inspection area is also arranged on the substrate.

The application also provides a battery unit, which comprises two fuel battery pole plates, a cathode side gas diffusion layer and an anode side gas diffusion layer; a cathode-side gas diffusion layer and an anode-side gas diffusion layer are disposed between the two fuel cell plates.

Further, the flow field regions of the two fuel cell plates have a position difference in the second direction.

The utility model provides a fuel cell polar plate includes the base plate, and the base plate has first face and second face, carries out the punching press to first face, forms the circulation passageway of sinking towards the second face on first face to form on the second face and keep away from the bellied protruding spine of first face, form the circulation passageway between two arbitrary adjacent protruding spines on the second face, the circulation passageway constitutes flow field area, from this, all have flow field area on first face and the second face. The fuel cell polar plate provided by the application can be used as a cathode plate, an anode plate and a bipolar plate, has a simple structure and is reliable to use.

The application also provides a battery unit, which comprises two fuel battery pole plates, a cathode side gas diffusion layer and an anode side gas diffusion layer; a cathode-side gas diffusion layer and an anode-side gas diffusion layer are disposed between the two fuel cell plates. By assembling a plurality of cell units, a fuel cell stack can be quickly constructed.

Drawings

Fig. 1 is a schematic structural diagram of a plate provided in the present application;

FIG. 2 is a schematic perspective view of the plate shown in FIG. 1;

FIG. 3 is an enlarged view of the structure enclosed in FIG. 2;

FIG. 4 is a sectional view taken along line A-A of FIG. 1;

fig. 5 is a schematic structural diagram of a battery unit provided in the present application;

fig. 6 is a schematic structural diagram of another battery cell provided in the present application.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying the present application are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of embodiments in many different forms than those described herein and that modifications may be made by one skilled in the art without departing from the spirit and scope of the application and it is therefore not intended to be limited to the specific embodiments disclosed below.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

Furthermore, the terms "first", "second" and "first" 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, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

The present application provides a fuel cell plate 100, which includes a substrate 110, the substrate 110 has a first surface 111 and a second surface 112, the first surface 111 and the second surface 112 are opposite to each other; stamping the first surface 111, forming a flow channel on the first surface 111 that is concave towards the second surface 112, and forming a convex ridge 121 on the second surface 112 that is convex away from the first surface 111; a flow channel is formed between any two adjacent raised ridges 121 on the second surface 112; the flow channel constitutes a flow field region 120 for guiding the flow of the reaction gas; flow field regions 120 are present on both first side 111 and second side 112.

First, it is to be explained that, for the fuel cell, the reaction gas includes a fuel gas and an oxidant gas. Wherein the fuel gas enters from an anode side of the fuel cell and the oxidant gas enters from a cathode side of the fuel cell; then, the fuel gas emits electrons at the anode end, and the electrons are conducted to the cathode through an external circuit to be combined with the oxidant gas to generate ions; under the action of the electric field, the ions migrate to the anode end through the electrolyte and react with the fuel gas to form a loop, and generate current.

One of the first reactive gas and the second reactive gas is a fuel gas, such as hydrogen; the other is an oxidant gas, such as oxygen. It will be readily appreciated that since oxygen is the major component of air, air may also be used as the oxidant gas for cost savings.

In one embodiment, the first reactant gas is a fuel gas; fuel gas enters the flow field region 120 through the first inlet 131, a portion of the fuel gas reacts with the oxidant gas to form water, and another portion of the fuel gas, which is not reacted, is discharged through the first outlet 132. Correspondingly, the second reactant gas is an oxidant gas, the oxidant gas enters the fuel cell through the first second inlet 141, and after reversing, the oxidant gas enters the flow field region 120 through the second inlet 142, a part of the oxidant gas reacts with the fuel gas to generate water, and another part of the oxidant gas does not participate in the reaction and is discharged through the second outlet 143.

Secondly, it should be explained that, when the polar plate provided by the present application is used to construct a fuel cell, the polar plate is connected to a membrane electrode, the flow field area 120 of the polar plate is attached to the membrane electrode, and the reaction gas enters the flow channel and contacts the membrane electrode.

Specifically, when the electrode plates and the membrane electrode constitute a fuel cell, one membrane electrode is disposed between the two electrode plates, and both sides of the membrane electrode are in contact with the flow field region 120 of one electrode plate, respectively. The flow field area 120 of one of the plates flows through oxidant gas, the flow field area 120 of the other plate flows through fuel gas, and the reaction gas is catalyzed by the membrane electrode to perform oxidation reaction, so that current is generated and water is generated.

The fuel cell electrode plate provided by the application can be used as a unipolar plate for fuel gas and can also be used as a unipolar plate for oxidant gas. When used as a monopolar plate, the first surface 111 or the second surface 112 of the plate is connected to the membrane electrode; the fuel cell operates, and the reactant gas passes through the first surface 111 or the second surface 112 of the electrode plate, contacts the membrane electrode, and undergoes a chemical reaction.

The fuel cell plate provided by the application can also be used as a bipolar plate. When used as a bipolar plate, the first face 111 of the plate is connected to one membrane electrode and the second face 112 of the plate is connected to the other membrane electrode; the fuel cell operates such that a first reactant gas passes over the first surface 111 and contacts the corresponding electrode to cause a chemical reaction, and a second reactant gas passes over the second surface 112 and contacts the corresponding electrode to cause a chemical reaction.

When the flow field region 120 is constructed on the substrate 110 by stamping, a stamping die is applied to the first surface 111 of the substrate 110 so that a part of the plate surface on the first surface 111 is recessed toward the second surface 112, and the recess becomes a flow channel of the flow field region 120 on the first surface 111. It is easy to understand that when the substrate 110 is subjected to the stamping force of the die, the first surface 111 and the second surface 112 are simultaneously deformed, the recesses on the first surface 111, i.e. the protrusions on the second surface 112, become the raised ridges 121 of the flow field area 120 on the second surface 112, and the flow channels of the flow field area 120 on the second surface 112 are formed between two adjacent protrusions.

Referring to fig. 4, in the embodiment, the first surface 111 is a left surface of the substrate 110, the second surface 112 is a right surface of the substrate 110, after the stamping, a recess is formed on the first surface 111, a protrusion is correspondingly formed on the second surface, and the non-stamped surfaces are in the same plane, that is, a single surface of the substrate 110 is protruded. At this time, the first surface 111 serves as an anode plate surface, and the undeformed surface serves as the raised ridges 121 of the flow field region 120 on the first surface 111 for abutting against the membrane electrode, and the recesses are for the flow of the reactant gases. The second surface 112 serves as a polar surface, the protrusions are used for abutting against the membrane electrode, and the undeformed surface between two adjacent protrusions is used for the circulation of the reaction gas.

Thus, due to the nature of the stamping, the depressions on either first side 111 correspond to the projections on one second side 112.

The substrate 110 with a single convex surface is constructed by punching, so that the structure of the polar plate can be simplified, and the universality of the polar plate can be improved.

It will be readily appreciated that for the first face 111, a recess is formed between adjacent undeformed surfaces, the recess serving as a flow path for the reactant gas. At this time, the first face 111 is fitted with a protrusion ridge 121 recessed into an "undeformed surface" constituting the flow channel, i.e., the first face 111.

When the flow channel extends along the first direction, correspondingly, any protruding ridge 121 also extends along the first direction; similarly, the plurality of protruding ridges 121 on the first surface 111 or the second surface 112 are disposed at intervals in the second direction.

The first direction may be regarded as a length direction of the flow field region 120, and the second direction may be regarded as a width direction of the flow field region 120.

By arranging the flow channel to extend along a straight line, on one hand, the structure of the flow field area 120 can be simplified, and polar plates can be conveniently formed; on the other hand, the straight-line extending flow channels are more favorable for the flow of the reaction gas without affecting the contact area of the reaction gas and the membrane electrode.

Further, the substrate 110 is provided with: a flow field region 120 for guiding the reaction gas to flow therethrough; a first inlet 131 provided at a first side of the flow field region 120 in a first direction; a first outlet 132 disposed at a second side of flow field region 120 along a first direction; when the fuel cell plate 100 is used as a plate for the first reactant gas, the first reactant gas can enter the flow field region 120 through the first inlet 131, and the first reactant gas can be discharged through the first outlet 132 by being guided by the flow field region 120.

The substrate 110 is further provided with: a second inlet one 141 provided at a third side of the flow field region 120; a second inlet second 142 disposed at a second side of the flow field region 120 along the first direction; a second outlet 143 disposed at a first side of the flow field region 120 in the first direction; when the fuel cell plate 100 is used as a plate for the second reactant gas, the second reactant gas can enter the second inlet two 142 through the first second inlet 141, and then enter the flow field region 120 through the second inlet two 142, and the second reactant gas can be discharged through the second outlet 143 by being guided by the flow field region 120.

By providing two inlets (the first inlet 141 and the second inlet 142) to supply the second reactant gas to the fuel cell, on the one hand, the flow rate and flow velocity of the second reactant gas entering the fuel cell can be regulated so that the second reactant gas reacts sufficiently. On the other hand, the second reactant gas can enter the second inlet 142 and the flow field region 120 after passing through the first second inlet 141, so that the flow time and the flow distance of the second reactant gas are long, and at this time, an auxiliary device may be disposed at the first second inlet 141 to adjust the state of the second reactant gas; for example, a humidifier is provided for humidifying the second reaction gas; as another example, a cooler may be provided for reducing the temperature … … of the second reactant gas to optimize the reaction of the fuel cell by changing the physical state of the second reactant gas.

When air is used as the oxidant gas, the amount of oxidant gas supplied to the fuel cell is larger than the amount of fuel gas supplied to the fuel cell. Therefore, it is possible to make the oxidant gas as the second reaction gas enter the flow field region 120 from the first inlet 141 and the second inlet 142, increase the amount of intake air through more inlets, and ensure a stable flow rate of air.

It should be further added that the third side may be a position different from the first side and the second side, for example, in the embodiment shown in fig. 1, the first direction is a left-right direction, the first side refers to a left side of the flow field region 120, the second side refers to a right side of the flow field region 120, and the third side may be an upper side of the flow field region 120 or a lower side of the flow field region 120. In this way, the structure of the substrate 110 can be effectively utilized, and the interaction between the second inlet 141 and the second inlet 142, the first outlet 132 and the second outlet 143 on the third side is also facilitated (the interaction purpose and method are described in detail below).

Alternatively, the third side may be the first side or the second side. The description continues with the orientation shown in fig. 1, i.e., the first direction is a left-right direction, the first side refers to the left side of the flow field region 120, and the second side refers to the right side of the flow field region 120. At this time, the third side may be the left side of the flow field region 120, or may be the right side of the flow field region 120. The first second inlet 141 may be provided in parallel with the other inlet, or may be provided on the left side or the right side of the other inlet.

Optionally, referring to fig. 1, at least two first inlets 141 are disposed on the substrate 110, and the at least two first inlets 141 are disposed side by side along an extending direction of a side of the corresponding flow field region 120. By increasing the number of the second inlets one 141, on the one hand, the flow rate of the second reactant gas can be increased to meet the gas supply needs of the fuel cell reaction; on the other hand, the second reaction gas can be guided to flow through various positions of the substrate 110, thereby making full use of the substrate 110. Meanwhile, when the auxiliary device is arranged at the first second inlet 141, the auxiliary device can respectively work on the first second inlets 141, so that the treatment effect on the second reaction gas is ensured.

Optionally, referring to fig. 1, at least two second inlets 142 are disposed on the substrate 110, and the at least two second inlets 142 are disposed side by side along the extending direction of the side edge of the corresponding flow field region 120; and/or at least two second outlets 143 are provided on the substrate 110, and the at least two second outlets 143 are arranged side by side along the extending direction of the side edge of the corresponding flow field region 120. By increasing the number of second inlets second 142, the flow of the second reactive gas into flow field region 120 can be increased. By increasing the number of second outlets 143, a greater flow of unreacted second reactant gas can be facilitated.

Similarly, optionally, at least two first inlets 131 are disposed on the substrate 110, and the at least two first inlets 131 are disposed side by side along the extending direction of the side edge of the corresponding flow field region 120; and/or at least two first outlets 132 are disposed on the substrate 110, and the at least two first outlets 132 are disposed side by side along the extending direction of the side edge of the corresponding flow field region 120.

By arranging the first inlet 131 and the first outlet 132, and the second inlet 142 and the second outlet 143 on two sides of the flow field region 120 opposite to each other in the first direction, after the reaction gas (the first reaction gas or the second reaction gas) enters the flow field region 120 from one side, the unreacted portion of the gas can directly flow out from the other side along the flow field region 120, thereby ensuring stable and efficient circulation of the reaction gas.

Further, the first inlet 131 is higher than the first outlet 132 in a second direction, which is perpendicular to the first direction. Since the first inlet 131 and the first outlet 132 have a height difference, the gas having a small mass flows through the entire flow field region 120 without floating above the flow field region 120 when entering from the first inlet 131 having a high position and flowing to the first outlet 132 having a low position, thereby enlarging a contact area between the reaction gas and the membrane electrode and promoting the fuel cell reaction.

Similarly, second inlet second 142 is higher in the second direction than second outlet 143 to facilitate channeling the reactant gas through the entire flow field region 120.

Alternatively, the first inlet 131 and the second outlet 143 are spaced apart in the second direction; and/or the first outlet 132 and the second inlet 142 are spaced apart in the second direction. Through setting up the entry of first reactant gas and the export of second reactant gas to and the export of first reactant gas and the entry of second reactant gas are on the collinear, on the one hand, can improve the utilization ratio of base plate 110 structure, and on the other hand, can simplify the structure of polar plate, improve the commonality of polar plate.

In order to improve the utilization rate of the reaction gas, it is necessary to ensure that the reaction gas is in full contact with the membrane electrode. In order to increase the contact area of the reactant gas with the membrane electrode and prevent the reactant gas from being trapped in the flow field region 120, in one embodiment, the flow field region 120 includes a plurality of raised ridges 121 spaced apart in the second direction, and any raised ridge 121 extends in the first direction.

Between any two adjacent raised ridges 121, a flow channel is formed, which also extends in the first direction. When the plate is connected to the membrane electrode, the raised ridges 121 abut against the membrane electrode, and the reactant gas passes through the flow channels and contacts the membrane electrode.

Specifically, reference may be made to fig. 1, wherein the first direction is a flowing direction of the reaction gas. The reaction gas enters flow field region 120 from the corresponding inlet (first inlet 131 or second inlet second 142), and flows from left to right or right to left to the position of the outlet (first outlet 132 or second outlet 143) along the flow channel. In the flowing process, part of reaction gas is catalyzed by the membrane electrode and participates in chemical reaction, and the other part of reaction gas is discharged through the outlet.

In order to increase the contact area of the reaction gas with the membrane electrode, the width of the raised ridge 121 in the second direction may be reduced without affecting the cell performance. It is easily understood that the width of the flow channel in the second direction affects the flow rate and flow velocity of the reaction gas, and thus, by reducing the width of the protruding ridge 121 on the basis of not changing the width of the flow channel, more flow channels can be constructed in the flow field region 120 having a limited area so that the reaction gas can better contact the membrane electrode.

Further, the flow field region 120 further includes a first limiting ridge 122 and a second limiting ridge 123 arranged at intervals in the up-down direction, and the plurality of protruding ridges 121 are disposed between the first limiting ridge 122 and the second limiting ridge 123.

By providing first and second limiting

ridges

122, 123, the extent of flow field region 120 can be defined to facilitate attachment of the plates to the membrane electrode, or assembly or mating with other structures in the fuel cell.

Optionally, the width of the limiting ridge (the first limiting ridge 122 or the second limiting ridge 123) in the second direction is larger than the width of the protruding ridge 121 in the second direction. It can be seen that the raised ridges 121 serve to construct a plurality of flow channels, and thus, the smaller the width of the raised ridges 121, the greater the number of flow channels. Different from the raised ridge 121, the limiting ridge is used as the boundary of the flow field region 120, and has a larger width, so that on one hand, the configuration of the flow field region 120 can be stabilized, and the raised ridge 121 is prevented from being deformed easily due to smaller width under stress; on the other hand, when the limiting ridge contacts the membrane electrode or other structures, the contact area of the limiting ridge and the membrane electrode is large, and the connection stability of the limiting ridge and the membrane electrode is improved.

Alternatively, the limiting ridge is spaced apart from an adjacent one of the raised ridges 121, and a flow channel is formed between the limiting ridge and the raised ridge 121. Alternatively, the stopper ridge may abut an adjacent one of the raised ridges 121 without a flow channel therebetween.

It is known that water is produced during the reaction of the fuel cell; it is easy to understand that the accumulation of a large amount of water in the cell structure is not favorable for the normal circulation of the reaction gas, and can also affect the stability of the cell.

Specifically, water generated by the reaction flows toward the outlet along with the reaction gas that does not participate in the reaction, and if the outlet is higher than the flow field region 120 or is close to the position of the flow field region 120, the reaction gas discharged from the flow field region 120 can normally pass through the outlet because of its smaller mass, but the discharged water is not easily discharged from the outlet with a higher position because of its larger mass, and is easily accumulated between the flow field region 120 and the outlet.

To facilitate draining, in one embodiment, at least a portion of first outlet 132 is positioned in the second direction below flow field region 120; and/or, at least a portion of second outlet 143 is along a second direction, below flow field region 120; so that water generated by the fuel cell reaction is discharged through the first outlet 132 or the second outlet 143.

Specifically, when water flows to the outlet (first outlet 132 or second outlet 143), it naturally flows downward due to its own weight and exits through first outlet 132 or second outlet 143 below flow field area 120.

Most fuel cell stacks on the market adopt an external humidifier to add humidity to the inside of the stack, so as to ensure the stable and reliable continuous operation of the stack. However, the addition of the external humidifier to act on the stack increases the operation power consumption of the stack, and as the operation time of the stack is prolonged, the actual operation performance of the stack is affected.

It is known that water is generated during the reaction of the fuel cell, and the water can be used to humidify the reaction gas, thereby humidifying the inside of the stack.

Thus, in one embodiment, the first outlet 132 and/or the second outlet 143 is in communication with the first second inlet 141 via a conduit; the water discharged through the first outlet 132 or the second outlet 143 acts on the second reaction gas in the second inlet 141 through a pipe.

It is easy to think that the moisture is discharged from the first outlet 132 or the second outlet 143 along with the reaction gas, so that when the discharged moisture directly flows to the second inlet 141 through the pipeline, a part of the reaction gas flows to the second inlet 141 along with the moisture. At this time, if the moisture mixed with the first reactant gas and discharged through the first outlet 132 enters the first inlet 141, the first reactant gas easily enters the second inlet 141 through the pipeline, thereby interfering with the normal flow of the second reactant gas and easily affecting the normal operation of the fuel cell.

Thus, in one embodiment, only the second outlet 143 is in communication with the second inlet 141 via a conduit. Thus, the moisture entrained by the unreacted second reaction gas flows out of the second outlet 143, and then enters the first inlet 141 again through the pipeline. At this time, by providing the pipeline, the second reactant gas can be humidified while increasing the flow rate of the second reactant gas at the first inlet 141.

In another embodiment, a steam-water separator may be disposed at the first outlet 132 and/or the second outlet 143, after the reactant gas leaves the fuel cell, the gas and the moisture in the reactant gas are separated by the steam-water separator, the gas can be re-input into the fuel cell through the backflow device to improve the utilization rate, and the moisture can be input into the second inlet 141 through the pipe to humidify the second reactant gas input into the fuel cell.

During the fuel cell reaction, a large amount of heat is generated. If the fuel cell works in a high-temperature environment for a long time, the reaction speed and the service life are influenced. In order to cool the fuel cell, in one embodiment, the substrate 110 is provided with a third inlet 151 and a third outlet 152; one of third inlet 151 and third outlet 152 is disposed at a first side of flow field region 120, and the other of third inlet 151 and third outlet 152 is disposed at a second side of flow field region 120; the coolant can enter the flow field region 120 through a third inlet 151 and can be discharged through a third outlet 152.

It should be noted that the coolant may be a cooling liquid or a cooling gas. For example, the coolant may be deionized water or a glycol solution. It is known that if the coolant and the reaction gas are simultaneously circulated on the same surface of the substrate 110, the coolant affects the flow rate and the flow rate of the reaction gas and also interferes with the normal reaction of the fuel cell. Therefore, when the fuel cell is operated, the reaction gas passes through the first surface 111 or the second surface 112 of the substrate 110 and contacts the membrane electrode; and the coolant passes through on second face 112 or the first face 11 of polar plate, through making coolant and reactant gas circulate on two different faces, the coolant neither can influence reactant gas's normal circulation, again can cool down the polar plate high-efficiently.

It should also be explained that in a fuel cell, at least the flow field region 120 of the plate is attached to the membrane electrode. During the reaction process, the reaction gas passes through the flow field region 120, contacts the membrane electrode, is catalyzed, and undergoes a chemical reaction to generate heat. Thus, the region of the substrate 110 where the temperature is highest is the location of the flow field region 120. Because of making the coolant flow through flow field area 120, on the one hand, can utilize the circulation channel in flow field area 120, increase the area of contact of coolant and polar plate to realize the heat dissipation better, on the other hand, can reduce the polar plate temperature through the main regional cooling that generates heat to the polar plate, high-efficiently.

To ensure the cooling effect, in one embodiment, referring to fig. 1 and 2, at least two third inlets 151 or at least two third outlets 152 are disposed on the same side of the substrate 110. By increasing the number of inlets and outlets, the flow rate of the coolant entering the flow field region 120 can be increased, thereby ensuring a cooling effect. Further, at least two third inlets 151 or at least two third outlets 152 are arranged at intervals in the second direction, thereby improving the utilization rate of the substrate 110.

Optionally, a positioning hole 161 is further disposed on the substrate 110.

In the process of preparing the plate by using the stamping process, the positioning hole 161 can be used for calibrating the position of each substrate 110 to be stamped, so as to ensure that the positions of the upstream field 120 and each inlet and outlet of any substrate 110 are relatively consistent, thereby ensuring the dimensional accuracy of the plate and improving the yield of plate preparation.

When assembling the fuel cell stack, the positioning holes 161 can be used to calibrate whether the positions of the two adjacent substrates 110 are consistent, so as to ensure the consistency of the stack and improve the yield of fuel cell preparation.

After the assembly of the fuel cell stack is completed, a positioning member (e.g., a positioning pin) can be inserted into the positioning hole 161, so as to shape the assembled fuel cell stack.

Optionally, a voltage inspecting area 171 is further disposed on the substrate 110.

Wherein, the voltage inspecting area 171 may be integrally formed with the substrate 110. At this time, the voltage inspection area 171 is a portion of the substrate 110. Referring to fig. 1, in the illustrated embodiment, the voltage inspecting area 171 is a portion of the substrate 110 that protrudes outward. In the process of bonding the substrate 110 to the membrane electrode, flowing the reaction gas, and generating the current, the current flows on the substrate 110. An external detection device is connected to the voltage inspection area 171, and can detect parameters such as current and voltage on the substrate 110, thereby confirming the reaction condition of the fuel cell.

In other embodiments, the voltage routing inspection area 171 can be other conductive structures capable of connecting external inspection equipment to the substrate 110. The voltage routing inspection region 171 conducts current, which can facilitate operator monitoring of the fuel cell reaction.

The present application also provides a battery unit, which includes two fuel battery plates 100A and 100B as described above, and further includes a cathode-side gas diffusion layer 1 and an anode-side gas diffusion layer 2; the cathode-side gas diffusion layer 1 and the anode-side gas diffusion layer 2 are provided between the two fuel cell plates 100A and 100B.

It is to be explained that the cathode-side gas diffusion layer 1 and the anode-side gas diffusion layer 2 are main structures constituting the fuel cell membrane electrode. Further, the anode-side gas diffusion layer 2 is provided with a CCM (catalyst coated membrane). Fuel gas (H)₂) Reaches the catalyst layer through the gas diffusion layer 2 on the anode side, and generates electrode reaction under the action of the catalyst, electrons generated by the electrode reaction reach the cathode through an external circuit by conduction of the catalyst layer, and simultaneously hydrogen ions reach the cathode under the action of the proton exchange membrane. After passing through the cathode-side gas diffusion layer 1, oxygen reacts with hydrogen ions and electrons in the presence of a catalyst to form water. Water is discharged through the cathode-side gas diffusion layer 1 and the anode-side gas diffusion layer 2.

In summary, the cathode-side gas diffusion layer 1 and the anode-side gas diffusion layer 2 can support the catalyst layer, stabilize the electrode structure, and also provide gas channels, electron channels, and water discharge channels for the electrode reaction.

Referring specifically to fig. 5 or 6, in the illustrated embodiment, one side of the cathode-side gas diffusion layer 1 contacts the plate 100A and the other side contacts the anode-side gas diffusion layer 2. The anode-side gas diffusion layer 2 contacts the cathode-side gas diffusion layer 1 on one side and the plate 100B on the other side. At this time, the surface of the plate 100A contacting the cathode-side gas diffusion layer 1 is for flowing of the oxidant gas, and the surface of the plate 100B contacting the anode-side gas diffusion layer 2 is for flowing of the fuel gas. Alternatively, the surface of the plate 100A facing away from the cathode-side gas diffusion layer 1, and the surface of the plate 100B facing away from the anode-side gas diffusion layer 2 may be flowed through by a coolant.

As can be seen from the above, the flow field area 120 of the plate 100 for contacting the gas diffusion layer (cathode-side gas diffusion layer 1 or anode-side gas diffusion layer 2) has a plurality of relatively convex ridges 121, and relatively concave flow channels are formed between two adjacent convex ridges 121. If the two plates 100A and 100B are configured to contact the flow field region 120 of the gas diffusion layer in the same configuration, after the plates 100A and 100B are stacked with the gas diffusion layer to form a cell, referring to fig. 5, the raised ridges 121 on the plate 100A are aligned with the flow channels on the plate 100B. With this structure, when the fuel cell stack is compressed, the plate 100A is stressed, the raised ridges 121 on the plate 100A can press against the membrane electrode, but the plate 100B is a flow channel corresponding to the membrane electrode, and the flow channel cannot support the membrane electrode. Therefore, the gas diffusion layer is easily deformed or even damaged due to unbalanced stress on both sides of the membrane electrode, and the structure of the fuel cell is damaged.

Therefore, in one embodiment, the two electrode plates 100A and 100B constituting the same battery cell have flow field regions 120 whose positions in the second direction are different from each other. Briefly, the flow field region 120 of one of the plates is lower than the flow field region 120 of the other plate in the second direction. In this manner, after the two plates 100A and 100B are stacked with the gas diffusion layers to form a battery cell, referring to fig. 6, the raised ridges 121 on the plate 100A are opposed to at least some of the raised ridges 121 on the plate 100B. Under the structure, when the fuel cell stack is compressed, the polar plate 100A is stressed, the raised ridges 121 on the polar plate 100A extrude the membrane electrode, meanwhile, at least part of the raised ridges 121 on the polar plate 100B correspond to the position of the membrane electrode, at least part of the raised ridges 121 on the polar plate 100B also extrude the membrane electrode, and the two ends of the membrane electrode are stressed, so that the state is stable.

Alternatively, after the two plates 100A and 100B are stacked with the gas diffusion layers to form a cell, the raised ridge 121 on either plate 100A faces one raised ridge 121 on plate 100B.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above examples only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A fuel cell plate (100) comprising a substrate (110), characterized in that the substrate (110) has a first face (111) and a second face (112), the first face (111) and the second face (112) being opposite sides of each other;

-stamping said first face (111), forming on said first face (111) flow channels that are concave towards said second face (112), and forming on said second face (112) convex ridges (121) that are convex away from said first face (111);

a flow channel is formed between any two adjacent raised ridges (121) on the second surface (112);

the flow channel forms a flow field region (120) for guiding the flow of the reaction gas;

the flow field region (120) is present on both the first (111) and the second (112) side.

2. The fuel cell plate (100) of claim 1, wherein any of the flow channels extends in a first direction, and a plurality of the flow channels are spaced apart in a second direction;

the first direction is perpendicular to the second direction.

3. The fuel cell plate (100) of claim 1, wherein the substrate (110) has disposed thereon:

a first inlet (131) provided at a first side of the flow field region (120) in a first direction;

a first outlet (132) disposed on a second side of the flow field region (120) along the first direction;

when the fuel cell plate (100) is used as a plate for a first reactant gas, the first reactant gas can enter the flow field region (120) through the first inlet (131), and the first reactant gas can be discharged through the first outlet (132) by being guided by the flow field region (120);

a second inlet one (141) provided at a third side of the flow field region (120);

a second inlet second (142) disposed at a second side of the flow field region (120) along the first direction;

a second outlet (143) provided at a first side of the flow field region (120) along the first direction;

when the fuel cell plate (100) is used as a plate of a second reactant gas, the second reactant gas can enter the second inlet II (142) through the second inlet I (141), and then enter the flow field region (120) through the second inlet II (142), and the second reactant gas can be discharged through the second outlet (143) by being guided by the flow field region (120).

4. The fuel cell plate (100) of claim 3, at least a portion of the first outlet (132) being below the flow field region (120);

and/or at least a portion of the second outlet (143) is below the flow field region (120).

5. The fuel cell plate (100) according to claim 4, the first outlet (132) and/or the second outlet (143) being in communication with the first second inlet (141) by a pipe;

the water discharged through the first outlet (132) or the second outlet (143) acts on the second reaction gas in the second inlet (141) through the pipe.

6. The fuel cell plate (100) according to any one of claims 1 to 5, wherein the base plate (110) is further provided with a third inlet (151) and a third outlet (152);

one of the third inlet (151) and the third outlet (152) is provided at a first side of the flow field region (120), and the other of the third inlet (151) and the third outlet (152) is provided at a second side of the flow field region (120);

coolant can enter the flow field region (120) through the third inlet (151) and can be discharged through the third outlet (152).

7. The fuel cell plate (100) according to any one of claims 1 to 5, wherein the base plate (110) is further provided with positioning holes (161).

8. The fuel cell plate (100) according to any one of claims 1 to 5, wherein the substrate (110) is further provided with a voltage routing inspection area (171).

9. A cell unit, characterized by comprising two fuel cell plates (100) according to any one of claims 1 to 8, further comprising a cathode-side gas diffusion layer (1) and an anode-side gas diffusion layer (2);

the cathode-side gas diffusion layer (1) and the anode-side gas diffusion layer (2) are provided between the two fuel cell plates (100).

10. The battery cell according to claim 9, characterized in that the flow field regions (120) of the two fuel cell plates (100) are positionally staggered in the second direction.