Cell and stack

Abstract

The utility model provides a cell and a stack. The single cell comprises a membrane electrode assembly and an anode plate and a cathode plate which are stacked on the two sides of the membrane electrode assembly in the stacking direction, and the anode plate and the cathode plate are each provided with a reaction surface facing the membrane electrode assembly. The single cell further comprises at least one first sealing ring arranged on the reaction surface of the anode plate and at least one second sealing ring arranged on the reaction surface of the cathode plate, each first sealing ring comprises a first protruding part protruding towards the membrane electrode assembly, and each second sealing ring comprises a second protruding part protruding towards the membrane electrode assembly. And a plurality of second sealing rings, each of which includes a second protrusion protruding toward the membrane electrode assembly, and the membrane electrode assembly is sandwiched between each of the first sealing rings and the corresponding second sealing ring in the stacking direction, the first protrusion of each first seal ring and the second protrusion of the corresponding second seal ring are offset relative to each other in a direction transverse to the stacking direction.

Description

Single cell and stack Technical Field

[0001] This disclosure relates to the field of fuel cell technology, and more specifically, to a single cell and a stack for a fuel cell. Background Technology

[0002] Fuel cells have become one of the main power generation technologies due to their high power generation efficiency, low environmental pollution, and high specific energy. As a typical fuel cell, the proton exchange membrane fuel cell (PEMFC) is a popular type of fuel cell used in vehicles. A PEMFC generally consists of a solid polymer electrolyte proton-conducting membrane, such as a perfluorosulfonic acid membrane. The anode and cathode typically comprise finely divided catalyst particles, usually platinum (Pt), supported on carbon particles and mixed with ionomers. The catalyst mixture is deposited on opposite sides of the membrane. The combination of the anode catalyst mixture, the cathode catalyst mixture, and the membrane defines the catalyst coating (CCM), while the catalyst coating and the two gas diffusion layers on either side define the membrane electrode assembly (MEA).

[0003] A fuel cell comprises a series of bipolar plates positioned between several MEAs (Mechanical Absorbers) within a stack, with the bipolar plates and MEAs located between two end plates. Each bipolar plate includes an anode plate and a cathode plate for adjacent individual cells within the stack. An anode gas flow field is positioned on the anode plate, allowing anode reactant gases to flow to their respective MEAs. A cathode gas flow field is positioned on the cathode plate, allowing cathode reactant gases to flow to their respective MEAs. However, in existing fuel cells, significant assembly forces are required to prevent leakage of anode gas, cathode gas, and coolant within the stack. These significant assembly forces can damage MEAs and even the anode and cathode plates, negatively impacting the reliability of the fuel cell stack.

[0004] Therefore, there is an urgent need in the field for a technical solution that can reduce the assembly force required to achieve reliable sealing of the fuel cell stack. Summary of the Invention

[0005] To address the problems in the prior art, this disclosure proposes an improved single cell for a fuel cell, comprising a membrane electrode assembly and an anode plate and a cathode plate stacked on both sides of the membrane electrode assembly along a stacking direction, wherein the anode plate and the cathode plate each have a reaction surface facing the membrane electrode assembly, the single cell further comprising at least one first sealing ring disposed on the reaction surface of the anode plate and at least one second sealing ring disposed on the reaction surface of the cathode plate, wherein each first sealing ring includes a first protrusion protruding toward the membrane electrode assembly, each second sealing ring includes a second protrusion protruding toward the membrane electrode assembly, and the membrane electrode assembly is sandwiched between each first sealing ring and a corresponding second sealing ring in the stacking direction, wherein the first protrusion of each first sealing ring and the second protrusion of the corresponding second sealing ring are offset relative to each other in a direction transverse to the stacking direction.

[0006] According to an alternative embodiment of the present disclosure, the membrane electrode assembly includes a proton exchange membrane and a gasket disposed around the edge of the proton exchange membrane, wherein the gasket is sandwiched between each first sealing ring and a corresponding second sealing ring in the stacking direction.

[0007] According to an alternative embodiment of the present disclosure, a first protrusion of each first sealing ring is arranged along its entire length, and a second protrusion of each second sealing ring is arranged along its entire length.

[0008] According to an optional embodiment of the present disclosure, each first sealing ring further includes a first flat portion having a flat surface, and each second sealing ring further includes a second flat portion having a flat surface, wherein the first protrusion and the second protrusion protrude toward the membrane electrode assembly relative to the first flat portion and the second flat portion, respectively, and the first protrusion and the first flat portion of each first sealing ring are aligned with the second flat portion and the second protrusion of the corresponding second sealing ring along the stacking direction.

[0009] According to an optional embodiment of the present disclosure, each first sealing ring includes two first flat portions and a first protrusion located between the two first flat portions, and each second sealing ring includes two second flat portions and a second protrusion located between the two second flat portions, wherein the first protrusion of each first sealing ring is aligned with one of the two second flat portions of the corresponding second sealing ring along the stacking direction, and one of the two first flat portions of each first sealing ring is aligned with the second protrusion of the corresponding second sealing ring along the stacking direction.

[0010] According to an optional embodiment of the present disclosure, each first sealing ring includes two first protrusions and a first flat portion located between the two first protrusions, and each second sealing ring includes two second flat portions and a second protrusion located between the two second flat portions, wherein the two first protrusions of each first sealing ring are respectively aligned with the two second flat portions of the corresponding second sealing ring along the stacking direction, and the first flat portion of each first sealing ring is aligned with the second protrusion of the corresponding second sealing ring along the stacking direction.

[0011] According to an optional embodiment of the present disclosure, each first sealing ring includes two first flat portions and a first protrusion located between the two first flat portions, and each second sealing ring includes two second protrusions and a second flat portion located between the two second protrusions, wherein the two first flat portions of each first sealing ring are respectively aligned with the two second protrusions of the corresponding second sealing ring along the stacking direction, and the first protrusion of each first sealing ring is aligned with the second flat portion of the corresponding second sealing ring along the stacking direction.

[0012] According to an optional embodiment of the present disclosure, each first sealing ring includes a plurality of first protrusions and a plurality of first flat portions, and each second sealing ring includes a plurality of second protrusions and a plurality of second flat portions, wherein each first protrusion of each first sealing ring is aligned with a corresponding second flat portion of the corresponding second sealing ring along the stacking direction, and each first flat portion of each first sealing ring is aligned with a corresponding second protrusion of the corresponding second sealing ring along the stacking direction.

[0013] According to an alternative embodiment of this disclosure, a first protrusion of each first sealing ring is configured to have a width that decreases as it approaches the membrane electrode assembly, and a second protrusion of each second sealing ring is configured to have a width that decreases as it approaches the membrane electrode assembly.

[0014] According to an alternative embodiment of the present disclosure, a first protrusion of each first sealing ring is configured to have a width greater than its height, and a second protrusion of each second sealing ring is configured to have a width greater than its height.

[0015] According to an alternative embodiment of the present disclosure, the anode plate includes a flow field region for guiding the flow of anode gas on its reaction surface and provides a plurality of through openings extending between the flow field region and the edge of the anode plate, and the single cell includes a plurality of first sealing rings arranged around the edge of the anode plate, the flow field region and each opening respectively.

[0016] According to an optional embodiment of the present disclosure, the cathode plate includes a flow field region for guiding the flow of cathode gas on its reaction surface and provides a plurality of through openings extending between the flow field region and the edge of the cathode plate, and the single cell includes a plurality of second sealing rings arranged around the edge of the cathode plate, the flow field region and each opening respectively.

[0017] Similarly, in order to address the problems in the prior art described above, this disclosure also proposes an improved fuel cell stack comprising a plurality of single cells as described in this disclosure stacked together along a stacking direction.

[0018] According to one alternative embodiment of this disclosure, the anode plate of each single cell is combined with the cathode plate of the adjacent single cell to form a bipolar plate.

[0019] This disclosure may be embodied in the illustrative embodiments shown in the accompanying drawings. However, it should be noted that the drawings are merely illustrative, and any variations contemplated under the teachings of this disclosure should be considered to be included within the scope of this disclosure. Attached Figure Description

[0020] The accompanying drawings illustrate exemplary embodiments of this disclosure. These drawings should not be construed as necessarily limiting the scope of this disclosure, wherein:

[0021] Figure 1 is a schematic exploded perspective view of a fuel cell stack according to one embodiment of the present disclosure;

[0022] Figure 2 is a schematic exploded perspective view of a portion of a single cell for a fuel cell according to one embodiment of the present disclosure;

[0023] Figure 3 is a schematic front view of the anode plate of the single cell shown in Figure 2;

[0024] Figure 4 is a schematic front view of the cathode plate of the single cell shown in Figure 2;

[0025] Figure 5 is a schematic assembled cross-sectional view of a portion of the single cell shown in Figure 2; and

[0026] Figure 6 is a schematic assembled cross-sectional view of a portion of a single cell for a fuel cell according to another embodiment of the present disclosure. Detailed Implementation

[0027] Further features and advantages of this disclosure will become more apparent from the following description with reference to the accompanying drawings. Exemplary embodiments of this disclosure are shown in the drawings, and the drawings are not necessarily drawn to scale. However, this disclosure can be implemented in many different forms and should not be construed as necessarily limited to the exemplary embodiments shown herein. Rather, these exemplary embodiments are provided merely to illustrate this disclosure and to convey the spirit and essence of this disclosure to those skilled in the art.

[0028] This disclosure aims to provide an improved single cell for fuel cells such as hydrogen-oxygen fuel cells, and a stack composed of multiple single cells. The single cell according to this disclosure, due to its novel sealing design, reduces the assembly force required to achieve sealing, thereby enabling reliable sealing of the single cell with relatively small assembly forces and reducing the risk of damage to individual components of the single cell due to high assembly forces. Furthermore, the sealing design of the single cell according to this disclosure also facilitates accurate positioning of the individual components of the single cell during assembly, thereby improving both the yield and reliability of the single cell. For the same reason, a stack composed of multiple single cells according to this disclosure can also achieve reliable sealing with relatively small assembly forces, and has high yield and reliability.

[0029] The following describes in detail, with reference to the accompanying drawings, various alternative but non-limiting embodiments of single cells and stacks for fuel cells according to this disclosure.

[0030] Referring to FIG1, a schematic exploded perspective view of a fuel cell stack 10 according to one embodiment of the present disclosure is shown. As shown in Figure 1, the fuel cell stack (also referred to as a fuel cell stack) 10 includes a plurality of generally plate-shaped or sheet-shaped single cells 100 stacked together along the stacking direction SS'. Each single cell 100 includes a membrane electrode assembly (MEA) 200, which is also generally plate-shaped or sheet-shaped and stacked together along the stacking direction SS', and an anode plate 300 and a cathode plate 400 located on both sides of the membrane electrode assembly 200. The anode plate 300 can deliver anode gas (e.g., hydrogen or other hydrogen-containing gas) from an anode gas source (e.g., a hydrogen storage tank) to one side of the membrane electrode assembly 200 (also referred to as the anode side), while the cathode plate 400 can deliver cathode gas (e.g., oxygen or other oxygen-containing gas) from a cathode gas source (e.g., the atmosphere) to the other side of the membrane electrode assembly 200 (also referred to as the cathode side). The anode gas and cathode gas delivered to both sides of the membrane electrode assembly 200 can undergo an electrochemical reaction to generate electrical energy, as described in more detail below. Specifically, the anode plate 300 and cathode plate 400 can be collectively referred to as monopolar plates, and the anode plate 300 of each single cell 100 can be combined with the cathode plate 400 of an adjacent single cell to form a bipolar plate 500. That is, the anode plate 300 of each bipolar plate 500 is used to supply anode gas to the membrane electrode assembly 200 of one single cell 100, and the cathode plate 400 of the bipolar plate 500 is used to supply cathode gas to the membrane electrode assembly 200 of another single cell 100 adjacent to that single cell 100. In this case, the stack 10 can also be considered to consist of multiple bipolar plates 500 and multiple membrane electrode assemblies 200 stacked together in an alternating manner. Of course, the above-described method of forming the stack 10 is merely exemplary. For a stack 10 having a single cell (mono-cell) form, the anode plates 300 and cathode plates 400 of two adjacent single cells 100 may not be combined.

[0031] Referring to FIG2, a schematic exploded perspective view of a portion of a single cell 100 for a fuel cell according to one embodiment of the present disclosure is shown. As shown in FIG2, the membrane electrode assembly 200 includes a proton exchange membrane 210, an anode catalyst layer 220, a cathode catalyst layer 230, an anode gas diffusion layer 240, and a cathode gas diffusion layer 250 stacked together along a stacking direction SS', wherein the anode catalyst layer 220 and the cathode catalyst layer 230 are located on opposite sides of the proton exchange membrane 210, the anode gas diffusion layer 240 is located on the side of the anode catalyst layer 220 opposite to the proton exchange membrane 210, and the cathode gas diffusion layer 250 is located on the side of the cathode catalyst layer 230 opposite to the proton exchange membrane 210. Additionally, the anode plate 300 of the single cell 100 abuts against the anode gas diffusion layer 240, and a plurality of anode gas channels 311 for anode gas flow (that is, for guiding anode gas flow) are provided on the surface facing the anode gas diffusion layer 240 (hereinafter referred to as the reaction surface). These anode gas channels 311 extend in a direction transverse to the stacking direction SS' and open toward the anode gas diffusion layer 240 in the stacking direction SS', so that the anode gas can flow in each anode gas channel 311 in a direction transverse to the stacking direction SS', and can enter the anode gas diffusion layer 240 and then be transported by the anode gas diffusion layer 240 to the anode catalyst layer 220. Similar to the anode plate 300, the cathode plate 400 of the single cell 100 abuts against the cathode gas diffusion layer 250, and has a plurality of cathode gas channels 411 for cathode gas flow (that is, for guiding cathode gas flow) on the surface facing the cathode gas diffusion layer 250 (hereinafter referred to as the reaction surface). These cathode gas channels 411 extend in a direction transverse to the stacking direction SS' and open toward the cathode gas diffusion layer 250 in the stacking direction SS', so that cathode gas can flow in each cathode gas channel 411 in a direction transverse to the stacking direction SS', and can enter the cathode gas diffusion layer 250 and then be transported by the cathode gas diffusion layer 250 to the cathode catalyst layer 230. It should be noted that, although in Figure 2, the anode plate 300 of a single cell 100 is combined with the cathode plate 400 of an adjacent single cell 100 to form a bipolar plate 500, and the cathode plate 400 of a single cell 100 is combined with the anode plate 300 of another adjacent single cell 100 to form another bipolar plate 500, as mentioned above, this is not limiting. In a stack 10 having a single cell form, the anode plate 300 and cathode plate 400 of a single cell 100 may not be combined with the cathode plate 400 and anode plate 300 of an adjacent single cell 100.

[0032] During operation of the fuel cell stack 10, the anolyte gas delivered to the anode catalyst layer 220 of each individual cell 100 undergoes an electrochemical reaction with the cathode gas delivered to its cathode catalyst layer 230 to generate electrical energy. Specifically, the anode gas input stream and the anode gas output stream flow through each individual cell 100 along the stacking direction SS'. The anode gas in the anode gas input stream is guided to the anode gas output stream by the anode gas channel 311 of the anode plate 300, and during this process, it is delivered to the anode catalyst layer 220 by the anode gas diffusion layer 240. Simultaneously, the cathode gas input stream and the cathode gas output stream also flow through each individual cell 100 along the stacking direction SS'. The cathode gas in the cathode gas input stream is guided to the cathode gas output stream by the cathode gas channel 411 of the cathode plate 400, and during this process, it is delivered to the cathode catalyst layer 230 by the cathode gas diffusion layer 250. At the anode catalyst layer 220, the anode gas decomposes into protons and electrons under the action of the catalyst material (i.e., an oxidation reaction occurs: 2H₂ → 4H₂). + +4e - ), of which, proton (H + Electrons can travel from the anode catalyst layer 220 through the proton exchange membrane 210 to the cathode catalyst layer 230, while electrons (e - Since it cannot pass through the proton exchange membrane 210 and can only reach the cathode catalyst layer 230 through an external circuit, it can supply power to the electrical load on the external circuit; while at the cathode catalyst layer 230, the cathode gas will react with protons (H) under the action of the catalyst material. + ) and electrons (e - The O₂ and H₂ combine to form water (i.e., a reduction reaction occurs: O₂ + 4H₂) + +4e - →2H2O). In this way, each single cell 100 can generate electricity through the redox reaction of the anode and cathode gases (i.e., the electrochemical reaction mentioned herein) to power electrical loads on an external circuit. Of course, water and heat will be generated as byproducts along with the electrical energy.

[0033] Referring to Figure 3, a schematic front view of the anode plate 300 of the single cell 100 shown in Figure 2 is shown. As shown in Figure 3, the anode plate 300 generally includes or can be divided into a flow field region (also referred to as a flow field portion) 310 and two conduit regions (also referred to as conduit portions) 320 located on both sides of the flow field region 310. It is worth mentioning that although in the embodiment shown in Figure 3, the flow field region 310 is located at the center of the anode plate 300 and the two conduit regions 320 are located on the two sides of the anode plate 300 respectively, this is not limiting. The flow field region 310 and the conduit regions 320 can also be arranged in other ways. For example, the anode plate 300 may include the flow field region 310 located at its center and the conduit regions 320 defined between the flow field region 310 and the edge of the anode plate 300 to surround the flow field region 310. Additionally, it should be noted that although the flow field region 310 and the pipe region 320 are separated by a dotted line in Figure 3, this only indicates that the flow field region 310 and the pipe region 320 are different parts of the anode plate 300 configured for different functions, and does not mean that there is an actual boundary line on the anode plate 300 that physically separates the flow field region 310 and the pipe region 320.

[0034] As shown in Figures 2 and 3, the anode plate 300 has a reaction surface 301 facing the anode gas diffusion layer 240 of the membrane electrode assembly 200 and a support surface 302 opposite to the reaction surface 301. The reaction surface 301 and the support surface 302 are spaced apart from each other along the thickness direction of the anode plate 300, which is in the same direction as the stacking direction SS'. The flow field region 310 has a plurality of anode gas channels 311 on the reaction surface 301. These anode gas channels 311 are configured to guide the flow of anode gas, thereby forming the anode gas flow field of the anode plate 300, and these anode gas channels 311 are spaced apart from each other by a plurality of anode gas separating ribs 312. Specifically, an anode gas separating rib 312 is formed between any two adjacent anode gas channels 311, as shown in Figure 2. These anode gas separating ribs 312 are designed to abut against the anode gas diffusion layer 240 so that each anode gas separating rib 312 can isolate the two anode gas channels 311 on its two sides from each other. Of course, it can also be said that these anode gas separation ribs 312 are spaced apart from each other by multiple anode gas flow channels 311. In short, the flow field region 310 has multiple alternating anode gas flow channels 311 and multiple anode gas separation ribs 312 on the reaction surface 301.

[0035] As shown in Figure 3, the two pipe regions 320 are provided with a plurality of openings 330 extending along the thickness direction through the anode plate 300 (i.e., extending from the reaction surface 301 to the support surface 302). In other words, these openings 330 are composed of a plurality of through holes provided in the anode plate 300 and are located between the flow field region 310 and the edge of the anode plate 300. Specifically, these openings 330 include an anode gas inlet 331, an anode gas outlet 332, a cathode gas inlet 333, a cathode gas outlet 334, a coolant inlet 335, and a coolant outlet 336. The anode gas inlet 331 allows the anode gas input flow to pass through the anode plate 300, the anode gas outlet 332 allows the anode gas output flow to pass through the anode plate 300, the cathode gas inlet 333 allows the cathode gas input flow to pass through the anode plate 300, the cathode gas outlet 334 allows the cathode gas output flow to pass through the anode plate 300, the coolant inlet 335 allows the coolant input flow to pass through the anode plate 300, and the coolant outlet 336 allows the coolant output flow to pass through the anode plate 300.

[0036] As shown in Figure 3, the flow field region 310 is further provided with multiple anode gas distribution channels 313 and multiple anode gas collection channels 315 on the reaction surface 301. The anode gas distribution channels 313 are located on one side of the anode gas flow field and are used to fluidly connect the anode gas inlet 331 to the anode gas flow field (i.e., each anode gas channel 311). The anode gas collection channels 315 are located on the other side of the anode gas flow field and are used to fluidly connect the anode gas outlet 332 to the anode gas flow field (i.e., each anode gas channel 311). Therefore, the anode gas distribution channels 313 and anode gas collection channels 315 respectively constitute the anode gas distribution flow field and the anode gas collection flow field located on both sides of the anode gas flow field, such that each anode gas channel 311 is fluidly connected to the anode gas inlet 331 at one end through the anode gas distribution flow field and to the anode gas outlet 332 at the other end through the anode gas collection flow field. In this configuration, the anolyte gas in the anolyte gas input stream flowing through the anolyte gas inlet 331 can be transported to each anolyte gas channel 311 by the anolyte gas distribution flow field. While flowing in the anolyte gas channels 311, the anolyte gas can be transported to the anolyte catalyst layer 220 by the anolyte gas diffusion layer 240 to participate in the electrochemical reaction as described above. The anolyte gas flowing through the anolyte gas channels 311 can be transported to the anolyte gas outlet 332 by the anolyte gas collection flow field, and then converges into the anolyte gas output stream flowing through the anolyte gas outlet 332. Specifically, similar to the anolyte gas channels 311, these anolyte gas distribution channels 313 can be separated from each other by multiple anolyte gas separation ribs 314, and these anolyte gas collection channels 315 can be separated from each other by multiple anolyte gas separation ribs 316.

[0037] As shown in Figures 2 and 3, the flow field region 310 has multiple coolant channels 317 on the support surface 302. These coolant channels 317 can be formed on the back side of the anode gas separation rib 312 and are configured to guide the coolant flow. Therefore, these coolant channels 317 constitute the coolant flow field of the anode plate 300. In addition, the flow field region 310 also has multiple coolant distribution channels (not shown) and multiple coolant collection channels (not shown) on the support surface 302. The coolant distribution channels are located on one side of the coolant flow field and are used to fluidly communicate the coolant inlet 335 with the coolant flow field (i.e., each coolant channel 317), thus constituting the coolant distribution flow field of the anode plate 300. The coolant collection channels are located on the other side of the coolant flow field and are used to fluidly communicate the coolant outlet 336 with the coolant flow field (i.e., each coolant channel 317), thus constituting the coolant collection flow field of the anode plate 300. In this configuration, the coolant in the coolant input stream flowing through the coolant inlet 335 can be delivered to each coolant channel 317 by the coolant distribution flow field; when flowing in the coolant channel 317, the coolant can absorb the heat generated by the electrochemical reaction to help the single cell 100 dissipate heat; and the coolant flowing through the coolant channel 317 can be delivered to the coolant outlet 336 by the coolant collection flow field, and then converge into the coolant output stream flowing through the coolant outlet 336.

[0038] As mentioned above, the main difference between the flow field region 310 and the conduit region 320 is that the flow field region 310 is the area or portion of the anode plate 300 used to guide the flow of anode gas and coolant on the surface of the anode plate 300, while the conduit region 320 is the area or portion of the anode plate 300 used to guide the flow of anode gas, cathode gas, and coolant through the anode plate 300. To prevent fluid leakage in the openings in the flow field region 310 and the conduit region 320, one or more sealing rings (hereinafter referred to as the first sealing ring) 340 made of an elastic material such as rubber can be provided on the reaction surface 301 of the anode plate 300. These first sealing rings 340 can be attached to the reaction surface 301 of the anode plate 300 by means such as adhesive bonding, and may include a first edge sealing ring 341 arranged along the entire edge of the anode plate 300 (i.e., around both the flow field region 310 and the pipe region 320), a first flow field region sealing ring 342 arranged around the flow field region 310, a first anode gas inlet sealing ring 343 arranged around the anode gas inlet 331, a first anode gas outlet sealing ring 344 arranged around the anode gas outlet 332, a first cathode gas inlet sealing ring 345 arranged around the cathode gas inlet 333, a first cathode gas outlet sealing ring 346 arranged around the cathode gas outlet 334, a first coolant inlet sealing ring 347 arranged around the coolant inlet 335, and a first coolant outlet sealing ring 348 arranged around the coolant outlet 336, etc. As described in more detail below, each of the plurality of first sealing rings 340 can be clamped between the anode plate 300 and the membrane electrode assembly 200 after the single cell 100 is assembled, thereby providing a reliable seal around the flow field region 310 and the respective openings in the conduit region 320 and along the edge of the anode plate 300 to prevent leakage of anode gas, cathode gas and coolant.

[0039] Referring to Figure 4, a schematic front view of the cathode plate 400 of the single cell 100 shown in Figure 2 is shown. As shown in Figure 4, the cathode plate 400 generally includes or can be divided into a flow field region (also referred to as a flow field portion) 410 and two conduit regions (also referred to as conduit portions) 420 located on both sides of the flow field region 410. It is worth mentioning that although in the embodiment shown in Figure 4, the flow field region 410 is located at the center of the cathode plate 400, and the two conduit regions 420 are located on the two sides of the cathode plate 400 respectively, this is not limiting. The flow field region 410 and the conduit regions 420 can also be arranged in other ways. For example, the cathode plate 400 may include the flow field region 410 located at its center and the conduit regions 420 defined between the flow field region 410 and the edge of the cathode plate 400, thereby surrounding the flow field region 410. Additionally, it should be noted that although the flow field region 410 and the pipe region 420 are separated by a dotted line in Figure 4, this only indicates that the flow field region 410 and the pipe region 420 are different parts of the cathode plate 400 configured for different functions, and does not mean that there is an actual boundary line on the cathode plate 400 that physically separates the flow field region 410 and the pipe region 420.

[0040] As shown in Figures 2 and 4, the cathode plate 400 has a reaction surface 401 facing the cathode gas diffusion layer 250 of the membrane electrode assembly 200 and a support surface 402 opposite to the reaction surface 401. The reaction surface 401 and the support surface 402 are spaced apart from each other along the thickness direction of the cathode plate 400, which is in the same direction as the stacking direction SS'. The flow field region 410 has a plurality of cathode gas channels 411 on the reaction surface 401. These cathode gas channels 411 are configured to guide the flow of cathode gas, thereby forming the cathode gas flow field of the cathode plate 400, and these cathode gas channels 411 are spaced apart from each other by a plurality of cathode gas separating ribs 412. Specifically, a cathode gas separating rib 412 is formed between any two adjacent cathode gas channels 411, as shown in Figure 2. These cathode gas separating ribs 412 are designed to abut against the cathode gas diffusion layer 250 so that each cathode gas separating rib 412 can isolate the two cathode gas channels 411 on its two sides from each other. Of course, it can also be said that these cathode gas separation ribs 412 are spaced apart from each other by multiple cathode gas flow channels 411. In short, the flow field region 410 has multiple cathode gas flow channels 411 and multiple cathode gas separation ribs 412 arranged alternately on the reaction surface 401.

[0041] As shown in Figure 4, the two pipe regions 420 are provided with a plurality of openings 430 extending along the thickness direction through the cathode plate 400 (i.e., extending from the reaction surface 401 to the support surface 402). In other words, these openings 430 are formed by a plurality of through holes provided in the cathode plate 400 and are located between the flow field region 410 and the edge of the cathode plate 400. Specifically, these openings 430 include an anode gas inlet 431, an anode gas outlet 432, a cathode gas inlet 433, a cathode gas outlet 434, a coolant inlet 435, and a coolant outlet 436. The anode gas inlet 431 allows the anode gas input flow to pass through the cathode plate 400, the anode gas outlet 432 allows the anode gas output flow to pass through the cathode plate 400, the cathode gas inlet 433 allows the cathode gas input flow to pass through the cathode plate 400, the cathode gas outlet 434 allows the cathode gas output flow to pass through the cathode plate 400, the coolant inlet 435 allows the coolant input flow to pass through the cathode plate 400, and the coolant outlet 436 allows the coolant output flow to pass through the cathode plate 400.

[0042] As shown in Figure 4, the flow field region 410 is further provided with multiple cathode gas distribution channels 413 and multiple cathode gas collection channels 415 on the reaction surface 401. The cathode gas distribution channels 413 are located on one side of the cathode gas flow field and are used to fluidly connect the cathode gas inlet 433 to the cathode gas flow field (i.e., each cathode gas channel 411). The cathode gas collection channels 415 are located on the other side of the cathode gas flow field and are used to fluidly connect the cathode gas outlet 434 to the cathode gas flow field (i.e., each cathode gas channel 411). Therefore, the cathode gas distribution channels 413 and cathode gas collection channels 415 respectively constitute the cathode gas distribution flow field and the cathode gas collection flow field located on both sides of the cathode gas flow field, such that each cathode gas channel 411 is fluidly connected to the cathode gas inlet 433 at one end through the cathode gas distribution flow field and to the cathode gas outlet 434 at the other end through the cathode gas collection flow field. In this configuration, the cathode gas in the cathode gas input stream flowing through the cathode gas inlet 433 can be transported to each cathode gas channel 411 by the cathode gas distribution flow field; while flowing in the cathode gas channel 411, the cathode gas can be transported to the cathode catalyst layer 230 by the cathode gas diffusion layer 250 to participate in the electrochemical reaction as described above; and the cathode gas flowing through the cathode gas channel 411 can be transported to the cathode gas outlet 434 by the cathode gas collection flow field, and then converged into the cathode gas output stream flowing through the cathode gas outlet 434. In particular, similar to the cathode gas channel 411, these cathode gas distribution channels 413 can be separated from each other by multiple cathode gas partition ribs 414, and these cathode gas collection channels 415 can be separated from each other by multiple cathode gas partition ribs 416.

[0043] As shown in Figures 2 and 4, the flow field region 410 has multiple coolant channels 417 on the support surface 402. These coolant channels 417 can be formed on the back side of the cathode gas separation rib 412 and are configured to guide the coolant flow. Therefore, these coolant channels 417 constitute the coolant flow field of the cathode plate 400. In addition, the flow field region 410 also has multiple coolant distribution channels (not shown) and multiple coolant collection channels (not shown) on the support surface 402. The coolant distribution channels are located on one side of the coolant flow field and are used to fluidly communicate the coolant inlet 435 with the coolant flow field (i.e., each coolant channel 417), thus constituting the coolant distribution flow field of the cathode plate 400. The coolant collection channels are located on the other side of the coolant flow field and are used to fluidly communicate the coolant outlet 436 with the coolant flow field (i.e., each coolant channel 417), thus constituting the coolant collection flow field of the cathode plate 400. In this configuration, the coolant in the coolant input stream flowing through the coolant inlet 435 can be delivered to each coolant channel 417 by the coolant distribution flow field; when flowing in the coolant channel 417, the coolant can absorb the heat generated by the electrochemical reaction to help the single cell 100 dissipate heat; and the coolant flowing through the coolant channel 417 can be delivered to the coolant outlet 436 by the coolant collection flow field, and then converge into the coolant output stream flowing through the coolant outlet 436.

[0044] As mentioned above, the main difference between the flow field region 410 and the pipe region 420 is that the flow field region 410 is the area or portion of the cathode plate 400 used to guide the flow of cathode gas and coolant on the surface of the cathode plate 400, while the pipe region 420 is the area or portion of the cathode plate 400 used to guide the flow of anode gas, cathode gas, and coolant through the cathode plate 400. To prevent fluid leakage in the openings in the flow field region 410 and the pipe region 420, one or more sealing rings (hereinafter referred to as second sealing rings) 440 made of an elastic material such as rubber can be provided on the reaction surface 401 of the cathode plate 400. These second sealing rings 440 can be attached to the reaction surface 401 of the cathode plate 400 by means such as adhesive bonding, and may include a second edge sealing ring 441 arranged along the entire edge of the cathode plate 400 (i.e., around both the flow field region 410 and the pipe region 420), a second flow field region sealing ring 442 arranged around the flow field region 410, a second anode gas inlet sealing ring 443 arranged around the anode gas inlet 431, a second anode gas outlet sealing ring 444 arranged around the anode gas outlet 432, a second cathode gas inlet sealing ring 445 arranged around the cathode gas inlet 433, a second cathode gas outlet sealing ring 446 arranged around the cathode gas outlet 434, a second coolant inlet sealing ring 447 arranged around the coolant inlet 435, and a second coolant outlet sealing ring 448 arranged around the coolant outlet 436, etc. As described in more detail below, each of the plurality of second sealing rings 440 can be clamped between the cathode plate 400 and the membrane electrode assembly 200 after the single cell 100 is assembled, thereby providing a reliable seal around the flow field region 410 and the respective openings in the conduit region 420 and along the edge of the cathode plate 400 to prevent leakage of anolyte gas, cathode gas and coolant.

[0045] The exemplary embodiments of the anode plate 300 and cathode plate 400 according to the present disclosure have been described above with the aid of Figures 3 and 4. An exemplary embodiment of the single cell 100 according to the present disclosure will be described below based on this. After the single cell 100 is assembled, the flow field region 310 of the anode plate 300 is aligned with the flow field region 410 of the cathode plate 400 along the stacking direction SS', and each opening 330 in the conduit region 320 of the anode plate 300 is aligned with a corresponding opening 430 in the conduit region 420 of the cathode plate 400 along the stacking direction SS'. Specifically, the anode gas inlet 331, anode gas outlet 332, cathode gas inlet 333, cathode gas outlet 334, coolant inlet 335, and coolant outlet 336 of the anode plate 300 are aligned with the anode gas inlet 431, anode gas outlet 432, cathode gas inlet 433, cathode gas outlet 434, coolant inlet 435, and coolant outlet 436 of the cathode plate 400 along the stacking direction SS', respectively, to allow anode gas, cathode gas, and coolant to flow through the single cell 100 along the stacking direction SS'. Additionally, each first sealing ring 340 on the reaction surface 301 of the anode plate 300 is at least partially aligned with a corresponding second sealing ring 440 on the reaction surface 401 of the cathode plate 400 along the stacking direction SS'. In other words, each first sealing ring 340 and its corresponding second sealing ring 440 are paired and disposed on both sides of the membrane electrode assembly 200, such that the membrane electrode assembly 200 is clamped between each first sealing ring 340 and its corresponding second sealing ring 440 in the stacking direction SS'. Specifically, the membrane electrode assembly 200 can be sandwiched in the stacking direction SS' between the first edge sealing ring 341 and the second edge sealing ring 441, between the first flow field region sealing ring 342 and the second flow field region sealing ring 442, between the first anode gas inlet sealing ring 343 and the second anode gas inlet sealing ring 443, between the first anode gas outlet sealing ring 344 and the second anode gas outlet sealing ring 444, between the first cathode gas inlet sealing ring 345 and the second cathode gas inlet sealing ring 445, between the first cathode gas outlet sealing ring 346 and the second cathode gas outlet sealing ring 446, between the first coolant inlet sealing ring 347 and the second coolant inlet sealing ring 447, and between the first coolant outlet sealing ring 348 and the second coolant outlet sealing ring 448.

[0046] Specifically, as shown in FIG2, the membrane electrode assembly 200 further includes a gasket 201 arranged around the edge of the proton exchange membrane 210. The gasket 201 surrounds the proton exchange membrane 210 and extends outward from the proton exchange membrane 210 in a direction transverse to the stacking direction SS', such that the gasket 201 is clamped between each first sealing ring 340 and a corresponding second sealing ring 440 in the stacking direction SS'. Of course, the gasket 201 is also provided with a plurality of openings extending through along the stacking direction SS', wherein each opening is aligned along the stacking direction SS' with a corresponding opening 330 of the anode plate 300 and a corresponding opening 430 of the cathode plate 400, so that anolyte gas, cathode gas and coolant can flow through the single cell 100 in the stacking direction SS'. In this configuration, the gasket 201, in cooperation with the first sealing ring 340 and the second sealing ring 440 arranged in pairs on both sides, can provide a reliable seal for each opening 330 in the flow field region 310 and the pipe region 320 of the anode plate 300 and the opening 430 in the flow field region 410 and the pipe region 420 of the cathode plate 400, thereby reliably preventing leakage of anode gas, cathode gas and coolant, and thus significantly improving the reliability of the single cell 100.

[0047] Referring to Figure 5, a schematic assembled cross-sectional view of a portion of the single cell 100 shown in Figure 2 is shown. It should be noted that although only one pair of first sealing rings 340 and second sealing rings 440 is shown in Figure 5, the description of this pair of first sealing rings 340 and second sealing rings 440 in Figure 5 also applies to other pairs of first sealing rings 340 and second sealing rings 440. As shown in Figure 5, the first sealing ring 340 is at least partially aligned with the second sealing ring 440 in the stacking direction SS', such that the gasket 201 of the membrane electrode assembly 200 is sandwiched between the first sealing ring 340 and the second sealing ring 440 in the stacking direction SS'. The first sealing ring 340 has a bottom 340a attached to the reaction surface 301 of the anode plate 300 and a top 340b spaced apart from the reaction surface 301, and the top 340b of the first sealing ring 340 includes a first protrusion 340c projecting in a direction away from the reaction surface 301 (i.e., toward the membrane electrode assembly 200). Similarly, the second sealing ring 440 has a bottom 440a attached to the reaction surface 401 of the cathode plate 400 and a top 440b spaced apart from the reaction surface 401, and the top 440b of the second sealing ring 440 includes a second protrusion 440c protruding in a direction away from the reaction surface 401 (i.e., toward the membrane electrode assembly 200). In particular, the first sealing ring 340 and the second sealing ring 440 are arranged such that the first protrusion 340c and the second protrusion 440c are not aligned along the stacking direction SS', but are offset relative to each other in a direction transverse to the stacking direction SS'. In this configuration, since the first protrusion 340c and the second protrusion 440c are offset relative to each other, the first protrusion 340c and the second protrusion 440c will not press against each other in the stacking direction SS' during the assembly of the single cell 100. This avoids misalignment of the membrane electrode assembly 200, anode plate 300 and cathode plate 400 during assembly due to the mutual pressing of the first protrusion 340c and the second protrusion 440c. This ensures the precise alignment of the flow field areas of the anode plate 300 and the cathode plate 400 and the corresponding openings, and also ensures the precise alignment of the flow field areas of the anode plate 300 and the cathode plate 400 with the corresponding gas diffusion layers. In other words, the above configuration can improve the accuracy of the assembly of the single cell 100. This not only helps to achieve reliable sealing of each opening and flow field area, thereby preventing seal failure, but also helps to ensure the accurate supply of anode gas, cathode gas and coolant, thereby ensuring the working efficiency of the single cell 100 and improving its power.Furthermore, it is worth mentioning that the assembly force applied in the stacking direction SS' to clamp the membrane electrode assembly 200, anode plate 300, and cathode plate 400 only needs to compress and deform the first protrusion 340c and the second protrusion 440c against the gasket 201 to form a reliable seal between the first sealing ring 340 and the gasket 201 and between the second sealing ring 440 and the gasket 201. Therefore, the above configuration also makes it possible to achieve a reliable seal of the single cell 100 with a relatively small assembly force, thereby significantly reducing the risk of damage to the membrane electrode assembly 200, anode plate 300, and cathode plate 400 during assembly, thus helping to improve the reliability of the single cell 100. Specifically, the first protrusion 340c can be arranged along the entire length of the first sealing ring 340, and the second protrusion 440c can be arranged along the entire length of the second sealing ring 440, thereby forming a reliable seal between the first sealing ring 340 and the gasket 201 along the entire length of the first sealing ring 340, and forming a reliable seal between the second sealing ring 440 and the gasket 201 along the entire length of the second sealing ring 440, thereby further improving the reliability of the single battery 100.

[0048] As shown in FIG5, the top 340b of the first sealing ring 340 further includes a first flat portion 340d having a flat surface (e.g., a surface parallel to the reaction surface 301). That is, the top 340b of the first sealing ring 340 may include a first protrusion 340c and a first flat portion 340d arranged alternately along a direction transverse to the stacking direction SS', wherein the first protrusion 340c protrudes relative to the first flat portion 340d in a direction away from the reaction surface 301 (i.e., toward the membrane electrode assembly 200). Similarly, the top 440b of the second sealing ring 440 also includes a second flat portion 440d having a flat surface (e.g., a surface parallel to the reaction surface 401). That is, the top 440b of the second sealing ring 440 may include a second protrusion 440c and a second flat portion 440d arranged alternately along a direction transverse to the stacking direction SS', wherein the second protrusion 440c protrudes relative to the second flat portion 440d in a direction away from the reaction surface 401 (i.e., toward the membrane electrode assembly 200). In addition, the first sealing ring 340 and the second sealing ring 440 are arranged such that the first flat portion 340d is aligned with the second protrusion 440c along the stacking direction SS', and the first protrusion 340c is aligned with the second flat portion 440d along the stacking direction SS'. In this configuration, after the single cell 100 is assembled, the gasket 201 of the membrane electrode assembly 200 will be sandwiched between the first flat portion 340d of the first sealing ring 340 and the second protrusion 440c of the second sealing ring 440, and also sandwiched between the first protrusion 340c of the first sealing ring 340 and the second flat portion 440d of the second sealing ring 440. This allows the gasket 201 to contact the surface of the first flat portion 340d on one side and the surface of the second flat portion 440d on the other side. The contact of these two surfaces can significantly increase the friction between the gasket 201 and the first sealing ring 340 and the second sealing ring 440, thereby more reliably preventing misalignment of the membrane electrode assembly 200, the anode plate 300 and the cathode plate 400 during assembly. This can more reliably ensure the sealing of the various openings and flow field areas of the anode plate 300 and the cathode plate 400, as well as the accurate supply of anode gas, cathode gas and coolant.

[0049] As shown in Figure 5, the first sealing ring 340 includes two first protrusions 340c and a first flat portion 340d located between the two first protrusions 340c, and the second sealing ring 440 includes two second flat portions 440d and a second protrusion 440c located between the two second flat portions 440d. Furthermore, the first sealing ring 340 and the second sealing ring 440 are arranged such that the first flat portion 340d is aligned with the second protrusion 440c along the stacking direction SS', and the two first protrusions 340c are respectively aligned with the two second flat portions 440d along the stacking direction SS'. In this configuration, since the first flat portion 340d is located between the two first protrusions 340c, the two first protrusions 340c can automatically align the second protrusion 440c with the first flat portion 340d during the assembly of the single battery 100, thereby not only further improving the accuracy of the single battery 100 assembly but also improving the convenience of the single battery 100 assembly. Furthermore, the above configuration allows for a double seal to be formed between the first sealing ring 340 and the gasket 201 through the two first protrusions 340c, thus more reliably preventing leakage of anode gas, cathode gas, and coolant from the anode plate 300 side. Alternatively, the configuration can be reversed, where the first sealing ring 340 includes two first flat portions 340d and a first protrusion 340c located between the two first flat portions 340d, and the second sealing ring 440 includes two second protrusions 440c and a second flat portion 440d located between the two second protrusions 440c. In this configuration, the two second protrusions 440c can automatically align the first protrusions 340c with the second flat portions 440d during single-cell assembly, further improving the accuracy and convenience of single-cell assembly, and forming a double seal between the second sealing ring 440 and the gasket 201 to more reliably prevent leakage of anode gas, cathode gas, and coolant from the cathode plate 400 side.

[0050] Referring to FIG6, a schematic assembly cross-sectional view of a portion of a single cell 100 for a fuel cell according to another embodiment of the present disclosure is shown. The main difference between the embodiment shown in FIG6 and the embodiment shown in FIG5 is that the first sealing ring 340 includes two first flat portions 340d and a first protrusion 340c located between the two first flat portions 340d. The first sealing ring 340 and the second sealing ring 440 are arranged such that the first protrusion 340c is aligned with one of the two second flat portions 440d along the stacking direction SS', and the second protrusion 440c is aligned with one of the two first flat portions 340d along the stacking direction SS'. It should be noted that the number of protrusions and flat portions described above with reference to FIG5 and FIG6 is merely exemplary and not limiting. The first sealing ring 340 may include any number of first protrusions 340c and first flat portions 340d, and the second sealing ring 440 may include any number of second protrusions 440c and second flat portions 440d. For example, the first sealing ring 340 may include a plurality of first protrusions 340c and a plurality of first flat portions 340d spaced apart from each other, and the second sealing ring 440 may include a plurality of second protrusions 440c and a plurality of second flat portions 440d spaced apart from each other. The first sealing ring 340 and the second sealing ring 440 are arranged such that each first protrusion 340c is aligned with a corresponding second flat portion 440d along the stacking direction SS', and each first flat portion 340d is aligned with a corresponding second protrusion 440c along the stacking direction SS'. In this configuration, multiple seals are formed between the first sealing ring 340 and the gasket 201 by the plurality of first protrusions 340c, and multiple seals are formed between the second sealing ring 440 and the gasket 201 by the plurality of second protrusions 440c, thereby more reliably preventing leakage of anolyte gas, catholyte gas, and coolant.

[0051] As shown in Figures 5 and 6, the first protrusion 340c of the first sealing ring 340 is configured such that its width t (e.g., a dimension measured along the direction transverse to the stacking direction SS') decreases with increasing distance from the reaction surface 301 of the anode plate 300 (in other words, with increasing proximity to the membrane electrode assembly 200), and the second protrusion 440c of the second sealing ring 440 is configured such that its width t decreases with increasing distance from the reaction surface 401 of the cathode plate 400 (in other words, with increasing proximity to the membrane electrode assembly 200). Specifically, the first protrusion 340c of the first sealing ring 340 is configured such that its width t is greater than its height h (e.g., a dimension measured along the stacking direction SS'), and the second protrusion 440c of the second sealing ring 440 is configured such that its width t is greater than its height h. In this configuration, it can be ensured that the first protrusion 340c and the second protrusion 440c are compressed and deformed along the stacking direction SS' during the assembly of the single cell 100, without bending and deforming in a direction transverse to the stacking direction SS', thereby ensuring that the first protrusion 340c and the second protrusion 440c form a reliable seal with the gasket 201.

[0052] The foregoing has described in detail, with reference to the accompanying drawings, alternative but non-limiting embodiments of the single cell and stack according to this disclosure. Modifications and additions to the technology and structure, as well as recombinations of features in the various embodiments, will be readily apparent to those skilled in the art without departing from the spirit and essence of this disclosure and should be considered as being within its scope. Therefore, such modifications and additions conceivable under the teachings of this disclosure should be considered part of this disclosure. The scope of this disclosure includes equivalent technologies known at the filing date of this disclosure and equivalent technologies not yet foreseen.

Claims

1. A single cell comprising a membrane electrode assembly (200) and an anode plate (300) and a cathode plate (400) stacked on both sides of the membrane electrode assembly (200) along a stacking direction (SS'), wherein, The anode plate (300) and the cathode plate (400) each have a reaction surface facing the membrane electrode assembly (200), characterized in that they further include at least one first sealing ring (340) disposed on the reaction surface of the anode plate (300) and at least one second sealing ring (440) disposed on the reaction surface of the cathode plate (400), wherein each first sealing ring (340) includes a first protrusion (340c) protruding toward the membrane electrode assembly (200), each second sealing ring (440) includes a second protrusion (440c) protruding toward the membrane electrode assembly (200), and the membrane electrode assembly (200) is sandwiched between each first sealing ring (340) and a corresponding second sealing ring (440) in the stacking direction (SS'), and wherein the first protrusion (340c) of each first sealing ring (340) and the second protrusion (440c) of the corresponding second sealing ring (440) are offset relative to each other in a direction transverse to the stacking direction (SS').

2. The single battery according to claim 1, characterized in that, The membrane electrode assembly (200) includes a proton exchange membrane (210) and a gasket (201) arranged around the edge of the proton exchange membrane (210), wherein the gasket (201) is sandwiched between each first sealing ring (340) and a corresponding second sealing ring (440) in the stacking direction (SS').

3. The single battery according to claim 1, characterized in that, The first protrusion (340c) of each first sealing ring (340) is arranged along its entire length, and the second protrusion (440c) of each second sealing ring (440) is arranged along its entire length.

4. The single cell according to any one of claims 1-3, characterized in that, Each first sealing ring (340) further includes a first flat portion (340d) having a flat surface, and each second sealing ring (440) further includes a second flat portion (440d) having a flat surface, wherein the first protrusion (340c) and the second protrusion (440c) protrude toward the membrane electrode assembly (200) relative to the first flat portion (340d) and the second flat portion (440d), respectively, and the first protrusion (340c) and the first flat portion (340d) of each first sealing ring (340) are aligned with the second flat portion (440d) and the second protrusion (440c) of the corresponding second sealing ring (440) along the stacking direction (SS').

5. The single battery according to claim 4, characterized in that, Each first sealing ring (340) includes two first flat portions (340d) and a first protrusion (340c) located between the two first flat portions (340d), and each second sealing ring (440) includes two second flat portions (440d) and a second protrusion (440c) located between the two second flat portions (440d), wherein the first protrusion (340c) of each first sealing ring (340) is aligned with one of the two second flat portions (440d) of the corresponding second sealing ring (440) along the stacking direction (SS'), and one of the two first flat portions (340d) of each first sealing ring (340) is aligned with the second protrusion (440c) of the corresponding second sealing ring (440) along the stacking direction (SS').

6. The single battery according to claim 4, characterized in that, Each first sealing ring (340) includes two first protrusions (340c) and a first flat portion (340d) located between the two first protrusions (340c), and each second sealing ring (440) includes two second flat portions (440d) and a second protrusion (440c) located between the two second flat portions (440d), wherein the two first protrusions (340c) of each first sealing ring (340) are respectively aligned with the two second flat portions (440d) of the corresponding second sealing ring (440) along the stacking direction (SS'), and the first flat portion (340d) of each first sealing ring (340) is aligned with the second protrusion (440c) of the corresponding second sealing ring (440) along the stacking direction (SS').

7. The single battery according to claim 4, characterized in that, Each first sealing ring (340) includes two first flat portions (340d) and a first protrusion (340c) located between the two first flat portions (340d), and each second sealing ring (440) includes two second protrusions (440c) and a second flat portion (440d) located between the two second protrusions (440c), wherein the two first flat portions (340d) of each first sealing ring (340) are respectively aligned with the two second protrusions (440c) of the corresponding second sealing ring (440) along the stacking direction (SS'), and the first protrusion (340c) of each first sealing ring (340) is aligned with the second flat portion (440d) of the corresponding second sealing ring (440) along the stacking direction (SS').

8. The single battery according to claim 4, characterized in that, Each first sealing ring (340) includes a plurality of first protrusions (340c) and a plurality of first flat portions (340d), and each second sealing ring (440) includes a plurality of second protrusions (440c) and a plurality of second flat portions (440d), wherein each first protrusion (340c) of each first sealing ring (340) is aligned with a corresponding second flat portion (440d) of the corresponding second sealing ring (440) along the stacking direction (SS'), and each first flat portion (340d) of each first sealing ring (340) is aligned with a corresponding second protrusion (440c) of the corresponding second sealing ring (440) along the stacking direction (SS').

9. The single cell according to any one of claims 1-3, characterized in that, The first protrusion (340c) of each first sealing ring (340) is configured to have a width that decreases as it approaches the membrane electrode assembly (200), and the second protrusion (440c) of each second sealing ring (440) is configured to have a width that decreases as it approaches the membrane electrode assembly (200).

10. The single battery according to claim 9, characterized in that, The first protrusion (340c) of each first sealing ring (340) is configured to have a width greater than its height, and the second protrusion (440c) of each second sealing ring (440) is configured to have a width greater than its height.

11. The single cell according to any one of claims 1-3, characterized in that, The anode plate (300) includes a flow field region that guides the flow of anode gas on its reaction surface and provides a plurality of through openings extending between the flow field region and the edge of the anode plate (300), and the single cell (100) includes a plurality of first sealing rings (340) arranged around the edge of the anode plate (300), the flow field region and each opening respectively.

12. The single cell according to any one of claims 1-3, characterized in that, The cathode plate (400) includes a flow field region that guides the flow of cathode gas on its reaction surface and provides a plurality of through openings extending between the flow field region and the edge of the cathode plate (400), and the single cell (100) includes a plurality of second sealing rings (440) arranged around the edge of the cathode plate (400), the flow field region and each opening respectively.

13. A fuel cell stack, characterized in that, Includes multiple single cells according to any one of claims 1-12 stacked together along the stacking direction (SS').

14. The fuel cell stack according to claim 13, characterized in that, The anode plate (300) of each single cell (100) is combined with the cathode plate (400) of the adjacent single cell (100) to form a bipolar plate (500).

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