Metal-supported solid oxide fuel cell structure and stack

Abstract

The application discloses a metal support type solid oxide fuel cell single cell structure and a fuel cell stack, and relates to the technical field of fuel cells; the single cell structure comprises a metal support cell sheet and a connecting body; the connecting body comprises an upper cover plate, a flow channel plate and a lower cover plate which are sequentially arranged; the upper cover plate is provided with a groove structure for accommodating the metal support cell sheet; the metal support cell sheet is embedded in the groove structure; opposite surfaces of the flow channel plate are respectively provided with a fuel gas side flow channel and an air side flow channel; an interlayer glass sealing layer is arranged in a non-flow channel sealing area between the upper cover plate and the flow channel plate and between the flow channel plate and the lower cover plate; and the interlayer glass sealing layer is used for sealingly connecting the upper cover plate, the flow channel plate and the lower cover plate. The technical scheme provided by the application can effectively reduce the deformation amount of the connecting body and the machining precision of the flow channel, so as to ensure the finished product quality of the single cell structure.

Description

Technical Field

[0001] This invention relates to the field of fuel cells, and in particular to a metal-supported solid oxide fuel cell single cell structure and stack. Background Technology

[0002] Solid oxide fuel cells (SOFCs) are all-solid-state electrochemical energy conversion devices that directly convert the chemical energy of fuel into electrical energy under medium- and high-temperature conditions. They offer advantages such as high power generation efficiency, strong fuel adaptability, low pollutant emissions, and suitability for distributed energy systems. Among the various SOFC configurations, metal-supported SOFCs (MS-SOFCs) use porous metal materials as the mechanical support matrix, on which electrodes, electrolytes, and other functional layers are fabricated. Compared to traditional ceramic-supported SOFCs, they offer higher mechanical strength, better thermal shock resistance, faster temperature rise and fall response, and potential low-cost manufacturing advantages.

[0003] In existing technologies, metal-supported SOFC single-cell structures mainly suffer from the following shortcomings: 1) The traditional manufacturing route of integrating the metal support and connector by brazing and then fabricating the functional layer as a whole makes the connector bear the thermal-mechanical load during sandblasting, thermal spraying and cooling. For large-area thin plate single cell structures, local thermal gradients and particle impacts are easily amplified by the plate size effect, which ultimately manifests as connector warping, uneven sealing surface, local deformation of flow channels and uneven stacking contact.

[0004] 2) If the upper cover plate, flow channel plate and lower cover plate are connected by high temperature brazing to form an integrated connector, the connector may generate residual stress and initial deformation during the assembly stage. For large-area thin plate single cell structure, the decrease in the flatness of the connector will directly reduce the assembly stability of the single cell structure and the success rate of sealing between the stack cells.

[0005] 3) If the gas-side flow channel and the air-side flow channel are formed in the upper cover plate, the lower cover plate, or the flow channel plate formed by multiple intermediate plates, the multiple plates need to be etched, stamped, cut, or stepped. Processing multiple plates and multiple processes will increase dimensional errors, burr risks, residual stress, and difficulty in sealing alignment, which is not conducive to the consistency of mass production.

[0006] It should be noted that the above content is only used to help understand the technical solution of the present invention, and does not represent an admission that the above content is prior art. Summary of the Invention

[0007] The main objective of this invention is to propose a metal-supported solid oxide fuel cell single cell structure and stack, aiming to effectively reduce the deformation of the connector and the processing accuracy of the flow channel, so as to ensure the quality of the finished single cell structure.

[0008] To achieve the above objectives, this invention proposes a metal-supported solid oxide fuel cell single-cell structure; specifically, the single-cell structure includes: Metal-supported solar cells; The connector includes an upper cover plate, a flow channel plate, and a lower cover plate arranged sequentially; the upper cover plate is provided with a groove structure for accommodating the metal support battery cell, and the metal support battery cell is embedded in the groove structure; the flow channel plate is provided with a gas-side flow channel and an air-side flow channel on opposite sides respectively; An interlayer glass sealing layer is disposed between the upper cover plate and the flow channel plate, and between the flow channel plate and the lower cover plate in the non-flow channel sealing area; the interlayer glass sealing layer is used to seal and connect the upper cover plate, the flow channel plate and the lower cover plate.

[0009] In one embodiment, the interlayer glass sealing layer is formed by screen printing glass paste, scraping glass paste, applying adhesive glass paste, or prefabricating a glass sealing layer.

[0010] In one embodiment, the groove structure includes a through-groove portion and a stepped portion surrounding the periphery of the through-groove portion; the metal-supported battery cell includes a central active region and an edge dense region surrounding the central active region, the porosity of the edge dense region being lower than that of the central active region; the central active region is aligned with the through-groove portion, and the edge dense region is mounted on the stepped portion.

[0011] In one embodiment, a glass sealing layer is provided at the gap between the dense edge region and the stepped portion, the glass sealing layer being used to seal and connect the dense edge region and the stepped portion.

[0012] In one embodiment, the inner cavity of the through groove is provided with a flexible conductive buffer layer, and the flexible conductive buffer layer is disposed between the central active region and the connector; the flexible conductive buffer layer is used to generate elastic or plastic deformation under the action of stacking preload and form multi-point contact with adjacent conductive surfaces.

[0013] In one embodiment, the connector is provided with a through-flow gas inlet and a gas outlet, the gas inlet and the gas outlet being respectively located on opposite sides of the gas side flow channel; Specifically, the gas-side flow channel includes a disturbance flow channel region, a first intake manifold region located on opposite sides of the disturbance flow channel region, and a first outlet manifold region. The first intake manifold region is connected to the gas inlet, and the first outlet manifold region is connected to the gas outlet. The disturbance flow channel region includes several parallel disturbance flow channels, each of which has a wave-shaped structure, a periodic deflection structure, or a segmented tortuous structure. Both the first intake manifold region and the first outlet manifold region include two equalizing chambers and several branch channels. The two equalizing chambers are symmetrically arranged on opposite sides of the gas inlet / gas outlet. One end of each branch channel is connected to the equalizing chamber, and the other end of each branch channel is connected to the disturbance flow channel.

[0014] In one embodiment, the connector is provided with one or more air inlets and one or more air outlets that are disposed through the connector, the air inlets and the air outlets being respectively disposed on opposite sides of the air side channel; Specifically, the air side channel includes a straight channel region, a second intake manifold region located on opposite sides of the straight channel region, and a second exhaust manifold region. The second intake manifold region is connected to the air inlet, and the second exhaust manifold region is connected to the air outlet. The straight channel region is provided with a plurality of parallel straight channels, each of which has a straight structure. Both the second intake manifold region and the second exhaust manifold region are provided with a plurality of diverter components, which are arranged in a straight array along the arrangement direction of the plurality of straight channels.

[0015] In one embodiment, the outer edge of the flow channel plate is provided with two leads, which are used to connect external test leads to monitor the electrical parameters of the corresponding single-cell structure; wherein the two leads can serve as alternating connection terminals or redundant connection terminals.

[0016] In one embodiment, the outer periphery of the single cell structure is provided with at least two open positioning notches, which are used to fit with the stack positioning posts required for forming the fuel cell stack; at least two of the positioning notches are respectively provided on opposite sides of the single cell structure.

[0017] To achieve the above objectives, the present invention proposes a metal-supported solid oxide fuel cell stack, comprising a plurality of single-cell structures as described in any of the above claims, wherein the plurality of single-cell structures are stacked together.

[0018] The beneficial effects of the technical solution of this invention: 1) This invention does not employ the manufacturing route of first integrating the metal support and connector and then fabricating the functional layer as a whole. Instead, the metal support cell is fabricated independently and then embedded into the groove structure of the connector's top cover after the functional layer is fabricated. Therefore, the connector does not need to participate as a whole in the fabrication process of the main functional layer of the metal support cell, and it no longer bears the heat input and particle impact during the thermal spraying process of the main functional layer. This reduces the risk of connector warpage and flatness degradation from the structural integration sequence, and also reduces connector deformation.

[0019] 2) The upper cover plate, flow channel plate, and lower cover plate of this invention are not connected by high-temperature integrated brazing, but rather by an interlayer glass sealing layer to achieve an airtight connection between the layers. This method can reduce the heat load and residual stress accumulation during the assembly stage of the connector, which is beneficial for maintaining the flatness of the connector.

[0020] 3) The present invention adopts a double-sided flow channel plate structure, in which the main fluid distribution structures of the gas side flow channel and the air side flow channel are respectively set on opposite sides of the same flow channel plate, so that the upper cover plate and the lower cover plate can be simplified into flat plate parts mainly for sealing and supporting, reducing the processing and assembly alignment errors of multi-plate flow channels, effectively improving processing accuracy, and thus ensuring the quality of the single-cell structure finished product. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is an exploded view of the overall structure of an embodiment of the single-cell structure provided by the present invention; Figure 2 An exploded view of the connector structure in one embodiment of the single-cell structure provided by the present invention; Figure 3 A schematic diagram of the connector and flexible conductive buffer layer in one embodiment of the single-cell structure provided by the present invention; Figure 4 A schematic diagram of the metal-supported battery cell in one embodiment of the single-cell structure provided by the present invention; Figure 5 A schematic diagram of the structure of the metal-supported battery cell and connector in one embodiment of the single-cell structure provided by the present invention; Figure 6 A schematic diagram of the gas-side flow channel in one embodiment of the single-cell structure provided by the present invention; Figure 7This is a schematic diagram of the air-side flow channel in one embodiment of the single-cell structure provided by the present invention.

[0023] Explanation of reference numerals in the attached figures: 10. Metal-supported solar cell; 101. Central active region; 102. Dense edge region; 20. Connector; 21. Gas inlet; 22. Gas outlet; 23. Air inlet; 24. Air outlet; 30. Top cover plate; 301. Groove structure; 3011. Through groove; 3012. Stepped section; 40. Flow channel plate; 50. Bottom cover plate; 60. Interlayer glass sealing layer; 70. Flexible conductive buffer layer; 80. Gas side flow 801, Disturbance flow channel area; 8011, Disturbance flow channel; 802, First intake manifold area; 8021, Pressure equalizing chamber; 8022, Flow divider; 803, First exhaust manifold area; 90, Air side flow channel; 901, Straight flow channel area; 9011, Straight flow channel; 902, Second intake manifold area; 9021, Flow divider; 903, Second exhaust manifold area; 100, Lug; 110, Positioning notch; The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0024] The technical solutions of this invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a portion of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0025] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0026] Furthermore, it should be noted that the descriptions involving "first," "second," etc., in this invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0027] This invention proposes a single-cell structure for a metal-supported solid oxide fuel cell.

[0028] Please see Figures 1 to 5 In one embodiment of the present invention, the single-cell structure includes: The metal-supported solar cell 10 integrates a metal support, a functional layer, and a current-collecting layer. The metal-supported solar cell 10 is the core electrochemical unit constituting the single-cell structure. It uses a porous metal material as a mechanical support substrate (i.e., a metal support). On the porous metal support, functional layers such as anode, electrolyte, and cathode are sequentially or compositely prepared through processes such as spraying, printing, and sintering. A current-collecting layer for collecting and discharging current is set on the corresponding surface of the functional layer. The connector 20 includes an upper cover plate 30, a flow channel plate 40 and a lower cover plate 50 arranged in sequence; the upper cover plate 30 is provided with a groove structure 301 for accommodating the metal support battery cell 10, and the metal support battery cell 10 is embedded in the groove structure 301; the flow channel plate 40 is provided with a gas-side flow channel 80 and an air-side flow channel 90 on opposite sides respectively. Interlayer glass sealing layer 60 is disposed in the non-flow channel sealing area between the upper cover plate 30 and the flow channel plate 40, and between the flow channel plate 40 and the lower cover plate 50; the interlayer glass sealing layer 60 is used to seal and connect the upper cover plate 30, the flow channel plate 40 and the lower cover plate 50.

[0029] The beneficial effects of the technical solution in this embodiment are as follows: 1) This invention does not adopt the manufacturing route of first integrating the metal support and connector 20 and then preparing the functional layer as a whole. Instead, the metal support battery cell 10 is prepared independently and then embedded into the groove structure 301 of the upper cover plate 30 of the connector 20 after the functional layer is prepared. As a result, the connector 20 does not need to participate in the preparation process of the main functional layer of the metal support battery cell 10 as a whole, and no longer bears the heat input and particle impact during the thermal spraying process of the main functional layer as a whole. This reduces the risk of warping and flatness deterioration of the connector 20 and reduces the deformation of the connector 20 from the structural integration sequence. At the same time, the metal support battery cell 10 and the connector 20 can be manufactured and inspected separately. If any component has a defect, it can be screened out before final sealing, reducing the overall scrap rate. Furthermore, the groove structure 301 can serve as the assembly positioning boundary of the metal support battery cell 10, improving the positional consistency of the metal support battery cell 10 in the connector 20. The depth of the groove structure 301 can be designed in coordination with the thickness of the metal support battery cell 10, the thickness of the glass sealing layer, and the compression amount of the flexible conductive buffer layer 70, so that the conductive contact interface forms a preset height relationship.

[0030] 2) Preferably, the upper cover plate 30, flow channel plate 40, and lower cover plate 50 are connected by interlayer glass sealing rather than high-temperature integrated brazing to achieve a gas-tight connection. Simultaneously, the interlayer glass sealing layer 60 is located in the non-flow channel sealing areas between the upper cover plate 30 and the flow channel plate 40, and between the flow channel plate 40 and the lower cover plate 50, avoiding the main gas flow channels. After sealing heat treatment, the glass or glass-ceramic material softens, wets, and fills the tiny gaps between the plates, forming a continuous interlayer gas-tight connection interface after cooling. The key function of this structure is to reduce the deformation of the connector 20 itself during assembly. Compared with high-temperature brazing, glass or glass-ceramic interlayer sealing does not require the melting of the brazing filler metal, intermetallic wetting and diffusion, and significant cooling and shrinkage processes. Therefore, it can reduce the residual stress caused by differences in thermal expansion and local stiffness between the upper cover plate 30, flow channel plate 40, and lower cover plate 50. For thin metal sheet components containing groove structures 301 and flow channels, this low-deformation interlayer connection method is more conducive to maintaining the overall flatness of the connector 20. Furthermore, the improved flatness of the connector 20 can directly improve the subsequent processes of embedding the metal-supported solar cell 10, glass sealing, and stacking sealing. Since the groove surface of the upper cover plate 30, the flow channel surface of the flow channel plate 40, and the support surface of the lower cover plate 50 maintain a high degree of flatness, it is easier to obtain a uniform glass sealing layer thickness and a stable conductive contact height after the metal-supported solar cell 10 is embedded; when multiple single-cell structures are stacked, the sealing surfaces between the cells are also more likely to form uniform compression, thereby improving the stacking sealing success rate and airtightness consistency. 3) The flow channel plate 40 of the present invention has a double-sided processing structure. One side of the flow channel plate 40 forms a gas-side flow channel 80, and the other side forms an air-side flow channel 90. The upper cover plate 30 and the lower cover plate 50 respectively cover the corresponding flow channel surfaces of the flow channel plate 40, and cooperate with the flow channel plate 40 to form a closed gas passage and an air passage. Compared with the traditional structure where multiple plates form separate gas flow channels and air flow channels, this invention concentrates the main fluid distribution structure on the same flow channel plate 40, which has the following advantages: a) It reduces the complex flow channel processing on the upper cover plate 30 and the lower cover plate 50, allowing the cover plate to be mainly used as a sealing and support structure; b) It reduces the risk of misalignment of flow channels and sealing paths in multiple plates; c) It reduces the number of processing steps and reduces dimensional fluctuations during etching, stamping, cutting and deburring processes; d) It improves the consistency of batch manufacturing of the connector 20, allowing the relative positions of the flow fields on the gas side and the air side to be controlled by the same flow channel plate 40; e) It facilitates the integral formation of an ear structure on the outer edge of the flow channel plate 40, enabling the flow channel plate 40 to have both fluid distribution and electrical signal output functions; f) In conjunction with the interlayer glass sealing structure, it can reduce the overall thermal deformation of the connector 20 while forming a closed gas channel.

[0031] Specifically, the interlayer glass sealing layer 60 is formed by screen printing glass paste, glass-ceramic paste, scraping glass paste, dispensing glass paste, or a prefabricated glass sealing layer. This configuration allows for flexible selection of coating or laying processes based on the different sealing area shapes and sizes between the upper cover plate 30 and the flow channel plate 40, and between the flow channel plate 40 and the lower cover plate 50. This ensures accurate placement of the interlayer glass sealing layer 60 in non-flow channel sealing areas and allows for uniform control of the interlayer sealing thickness through the prefabricated glass sealing layer, improving the reliability and consistency of the interlayer airtight connection. Furthermore, all of the above forming methods are low-temperature or medium-temperature sealing processes, eliminating the need for solder melting and significant cooling shrinkage, further reducing the thermal stress input and deformation risk of the connector 20 during the interlayer connection stage. It should be noted that, after understanding the technical solution of this application, those skilled in the art can conceive of other equivalent cryogenic sealing materials without creative effort, and these should also fall within the scope of protection of this application.

[0032] As a preferred embodiment of the above embodiments, refer to Figures 3 to 5The groove structure 301 includes a through groove 3011 and a stepped portion 3012 surrounding the through groove 3011. The metal-supported solar cell 10 includes a central active region 101 and an edge dense region 102 surrounding the central active region 101. The porosity of the edge dense region 102 is lower than that of the central active region 101. The central active region 101 is aligned with the through groove 3011, and the edge dense region 102 is mounted on the stepped portion 3012. This configuration is advantageous because, in some metal-supported SOFC structures, the edges of the porous metal-supported solar cell 10 directly participate in the sealing process, and the openings and connecting holes at the porous edges can easily become lateral leakage channels. If the glass sealing layer described below directly contacts the high-porosity edge, the glass may locally penetrate the porous network during the sealing process, resulting in uneven sealing layer thickness, localized stress concentration, and discontinuous sealing interface. For the reasons mentioned above, the present invention forms an edge-dense region 102 in the outer peripheral inactive area of ​​the metal-supported solar cell 10, so that the porosity of the edge of the metal-supported solar cell 10 is significantly lower than that of the central active region 101, and a continuous edge-dense region 102 is formed. The edge-dense region 102 has the following functions: 1) blocking or significantly reducing the path of gas leakage laterally along the edge of the porous metal-supported solar cell 10, so that gas diffusion is mainly confined to the designed central active region 101 and the flow channel region; 2) providing a relatively dense, flat and continuous contact interface for the glass sealing layer, so that the glass forms a stable sealing layer during the sealing process, rather than uncontrollably seeping into the porous edge; 3) improving the local stiffness of the outer periphery of the metal-supported solar cell 10, so that the edge-dense region 102 has a higher shape retention capability during glass sealing, stacking pre-tightening and thermal cycling; 4) serving as the circumferential support boundary when the metal-supported solar cell 10 is embedded in the groove structure 301 of the upper cover plate 30, improving the positional consistency and sealing thickness stability between the metal-supported solar cell 10 and the groove structure 301. In this embodiment, the dense edge region 102 is formed by edge pressing, compaction, rolling, molding, or hot pressing. It should be noted that, after understanding the technical solution of this application, those skilled in the art can conceive of other equivalent local densification methods without creative effort, and these should also fall within the protection scope of this application.

[0033] Furthermore, a glass sealing layer (not shown in the attached figure) is provided in the gap between the dense edge region 102 and the step portion 3012. The glass sealing layer is used to seal the connection between the dense edge region 102 and the step portion 3012. Thus, the glass sealing layer is positioned between the dense edge region 102 of the metal-supported battery cell 10 and the groove structure 301 of the upper cover plate 30. This glass sealing layer is not only a common airtight material but also serves as a structural connection, gap compensation, circumferential restraint, and stress buffer. Specifically, the glass sealing layer can be formed by screen printing, dispensing, scraping, spraying, prefabricated glass rings, or composite glass seals. During the sealing process, the glass material softens and wets the adjacent interfaces, forming a continuous sealing layer after cooling and solidification. Since the glass sealing layer of this invention mainly acts on the low-porosity dense edge region 102, rather than the high-porosity porous edge, the risk of excessive glass penetration into the porous structure can be reduced, which is beneficial for forming a more stable sealing thickness and a more continuous sealing interface. Meanwhile, the sealing temperature of the glass sealing layer can be lower than that of traditional integrated metal brazing to reduce the risk of thermal deformation of the connector 20; its thermal expansion characteristics should be matched with those of the metal-supported battery cell 10 and the upper cover plate 30 to reduce thermal stress concentration at the sealing interface during thermal cycling. In other embodiments, brazing or laser sealing can be used to seal the metal-supported battery cell 10 to the connector groove structure 301, which should also fall within the scope of protection of this application.

[0034] Furthermore, the rear-embedded glass sealing layer and the interlayer glass sealing layer 60 of the aforementioned connector 20 together constitute the dual-stage low-deformation gas-tight structure of the present invention; that is, the upper cover plate 30, the flow channel plate 40 and the lower cover plate 50 inside the connector 20 form a first low-deformation gas-tight structure through the interlayer glass sealing layer 60; the dense region 102 at the edge of the metal-supported battery cell 10 and the groove structure 301 of the upper cover plate 30 form a second low-deformation gas-tight structure through the glass sealing layer; the first layer structure reduces the assembly deformation of the connector 20 itself, and the second layer structure reduces the integration deformation of the metal-supported battery cell 10 and the connector 20, and the two together improve the flatness maintenance capability and the success rate of interlayer sealing after the single cell structure area is enlarged.

[0035] Furthermore, a flexible conductive buffer layer 70 is provided in the inner cavity of the through-slot 3011, and the flexible conductive buffer layer 70 is disposed between the central active region 101 and the connector 20; the flexible conductive buffer layer 70 is designed to undergo elastic or plastic deformation under the action of stacking preload and form multi-point contact with adjacent conductive surfaces; thus, during the stacking assembly process, the flexible conductive buffer layer 70 is located between the conductive contact surface of the central active region 101 and the corresponding conductive surface of the connector 20. When an axial preload is applied to the stack, the flexible conductive buffer layer 70 can undergo elastic or plastic deformation under pressure, thereby adaptively filling the space between the central active region 101 and the connector 20. The minute gaps and height differences caused by processing errors, slight warping of the plates, or assembly deviations transform the initial point or line contact between the flexible conductive buffer layer 70 and the adjacent upper and lower conductive surfaces into surface or multi-point contact. This significantly increases the actual conductive contact area, reduces the peak value of local contact resistance, improves the uniformity of current distribution, and avoids local stress concentration and contact interface damage caused by rigid contact. Simultaneously, during the thermal cycling of the fuel cell stack, the flexible conductive buffer layer 70 can absorb the contact interface displacement and pressure fluctuations caused by differences in the thermal expansion coefficients of various components through its own deformation recovery or further compression, thus maintaining a stable and reliable conductive contact state during long-term operation. In short, the flexible conductive buffer layer 70 has the following functions: 1) compensating for minor flatness deviations between the connector 20, the battery cells, and the cover plate; 2) increasing the actual conductive contact area and reducing the peak value of local contact resistance; 3) reducing local stress concentration caused by rigid contact; 4) improving electrical contact stability after thermal cycling; and 5) maintaining a relatively stable conductive contact interface in the reducing atmosphere on the fuel gas side. It should be noted that those skilled in the art can also individually place the flexible conductive buffer layer 70 on the gas side, air side, or both conductive contact areas. Its thickness, porosity, mesh size, and compression amount can be selected based on the stacking preload, target contact resistance, and cell flatness, and should also fall within the scope of protection of this application. In this embodiment, the flexible conductive buffer layer 70 is configured as a nickel mesh, nickel felt, nickel foam, or nickel-based alloy mesh. It should also be noted that those skilled in the art, after understanding the technical solution of this application, can readily conceive of other high-temperature resistant conductive porous structures as flexible conductive buffer layers without creative effort, and these should also fall within the scope of protection of this application.

[0036] As a preferred embodiment of the above embodiments, refer to Figure 6The connector 20 is equipped with a through-type gas inlet 21 and a gas outlet 22, which are respectively located on opposite sides of the gas side flow channel 80. Specifically, the gas side flow channel 80 includes a disturbance flow channel region 801, a first intake manifold region 802 located on opposite sides of the disturbance flow channel region 801, and a first exhaust manifold region 803. The first intake manifold region 802 is connected to the gas inlet 21, and the first exhaust manifold region 803 is connected to the gas outlet 22. The disturbance flow channel region 801 includes a plurality of parallel disturbance flow channels 8011, each disturbance flow channel 8011... 011 has a wave-shaped structure, a periodic deflection structure, or a segmented tortuous structure; both the first intake manifold region 802 and the first outlet manifold region 803 include two equalizing chambers 8021 and several branch channels 8022. The two equalizing chambers 8021 are symmetrically arranged on opposite sides of the gas inlet 21 / gas outlet 22 (i.e., the two equalizing chambers 8021 are symmetrically arranged on opposite sides of the gas inlet 21, and the two equalizing chambers 8021 are symmetrically arranged on opposite sides of the gas outlet 22). One end of the branch channel 8022 is connected to the equalizing chamber 8021, and the other end of the branch channel 8022 is connected to the disturbance channel 8011. With this configuration, the gas side of the present invention adopts a wave-shaped, periodic deflection, segmented tortuous, or equivalent disturbance channel structure. Unlike the air side, the gas side places more emphasis on the residence time, lateral mixing, and uniformity of concentration distribution of the fuel gas. The perturbation channel 8011 can improve fuel utilization within the reaction region by periodically changing the flow direction, extending the local flow path, and enhancing lateral diffusion. The technical effects of the gas-side perturbation-enhanced flow field include: 1) extending the effective residence time of the gas in the active region; 2) enhancing lateral mixing between adjacent channels or within the channel, reducing local concentration differences; 3) alleviating the problem of excessive reaction on the inlet side and insufficient reaction on the outlet side; and 4) improving fuel utilization and reaction uniformity while avoiding the use of high-pressure, elongated serpentine channels. The peaks, troughs, bending periods, channel width, channel depth, and perturbation amplitude of the gas-side channel 80 can be optimized based on the single-cell structure dimensions, fuel flow rate, target fuel utilization rate, and allowable pressure drop.

[0037] Furthermore, this invention provides a pressure equalization chamber 8021 on the gas side as a single large internal manifold. Gas first enters the pressure equalization chamber 8021 through the gas inlet 21, where pressure buffering and flow equalization are completed. Then, it enters the disturbance flow channel region 801 via the two side branch channels 8022. Compared to multiple small manifolds directly connected in parallel for gas intake, the single large internal manifold has a larger buffer space and is less sensitive to inlet flow fluctuations and local processing errors. The two side branch channels 8022 reduce the risk of localized high flow velocities at a single inlet and uneven distribution over a wide area. This structure is particularly suitable for large-area metal-supported SOFC single cells, helping to improve the consistency of gas distribution at the inlet of the reaction zone. Preferably, the two side branch channels 8022 are respectively arranged in different regions on the gas flow field inlet side, allowing gas to enter the disturbance flow channel 8011 from the two side branch channels 8022 to improve flow uniformity in the width direction. The gas outlet 22 can be configured as a single outlet, dual outlet, or multi-outlet structure depending on the flow field arrangement.

[0038] As a preferred embodiment of the above embodiments, refer to Figure 6 The connector 20 is equipped with three through-flow air inlets 23 and three air outlets 24, which are respectively located on opposite sides of the air-side flow channel 90. Specifically, the air-side flow channel 90 includes a straight flow channel region 901, a second intake manifold region 902 located on opposite sides of the straight flow channel region 901, and a second exhaust manifold region 903. The second intake manifold region 902 is connected to the three air inlets 23, and the second exhaust manifold region 903 is connected to the three air outlets 24. The straight flow channel region 901 is provided with a plurality of parallel straight flow channels 9011, each of which has a straight structure. The second intake manifold region 902 and the second exhaust manifold region 903 are each provided with a plurality of diverter elements 9021, which are arranged in a straight array along the arrangement direction of the plurality of straight flow channels 9011. With this configuration, the air side of the present invention adopts a straight-through low-pressure drop flow channel. The air-side flow channel 90 extends along the mainstream direction and connects to the multi-inlet / multi-outlet air-side manifold. The design focus of the air-side flow channel 90 is to reduce pressure drop, improve high-flow oxygen supply capacity, and enhance convective heat dissipation. A three-inlet / three-outlet manifold configuration is preferred for the air side, but it can also be adjusted to a two-inlet / two-outlet, three-inlet / multi-outlet, or other multi-inlet / multi-outlet distributed structure depending on the single-cell structure size and target airflow. Through multiple intake and exhaust positions, air can be more evenly distributed within a wide reaction area, avoiding localized flow deviations and heat concentration at the outlet caused by a single inlet. The technical benefits of this air-side structure include: 1) reducing air-side pressure drop and minimizing system auxiliary power consumption; 2) improving the uniformity of air coverage within a wide active area; 3) enhancing convective heat dissipation and reducing the risk of localized hotspot formation; and 4) avoiding the processing difficulties and deformation risks associated with overly complex perturbation structures on the air side.

[0039] Furthermore, the air side of this invention employs a multi-inlet, multi-outlet manifold flow pattern. Taking a three-inlet, three-outlet structure as an example, the three inlet manifolds correspond to different zones of the airflow field, and the three outlet manifolds correspond to the exhaust areas. Air enters the straight-through channel 9011 through multiple inlet positions and exits through multiple outlets. The key to this structure is to transform the large-flow air supply from a single-point centralized input to a multi-point distributed input, thereby reducing the flow differences between different regions in a wide-area single cell. Its technical effects include: 1) improving the uniformity of oxygen supply on the air side; 2) reducing back pressure and heat accumulation at the air outlet 24; 3) improving the uniformity of the temperature field on the air side; and 4) improving the thermal management capability after scaling up a large-area single cell.

[0040] In summary, this invention employs a heterogeneous composite flow field that combines a direct-flow, low-pressure-drop channel on the air side with a perturbation-enhanced channel on the gas side. The air side focuses on meeting the requirements of high-flow-rate oxygen supply and heat dissipation, while the gas side focuses on improving fuel residence time, lateral mixing, and reaction utilization, thereby achieving functional decoupling between the gas and gas sides.

[0041] As a preferred embodiment of the above embodiments, refer to Figure 5 The outer edge of the flow channel plate 40 is provided with two leads 100, which are used to connect external test leads to monitor the electrical parameters of the corresponding single cell structure. These two leads 100 can serve as alternating or redundant connection terminals. This design takes into account the need for stable, low-resistance contact between the connector 20 and the metal-supported solar cell 10 in an SOFC stack. If the connector 20 has slight warping or surface height differences, rigid contact can easily lead to localized point or line contact, resulting in uneven current distribution, increased contact resistance, and localized hot spots. Furthermore, if each layer of connector 20 lacks an externally connectable monitoring lead, it is difficult to promptly locate voltage anomalies, localized short circuits, contact degradation, or abnormal gas distribution in a particular layer after stack assembly. For these reasons, the present invention provides two leads 100 on the outer edge of the flow channel plate 40 that are electrically connected to the main body of the flow channel plate 40. The lugs 100 can be integrally formed by stamping, etching, or cutting the flow channel plate 40, or connected to the main body of the flow channel plate 40 by welding, riveting, diffusion bonding, brazing, or other low-resistance connection methods. The two lugs 100 can extend from the side or periphery of the fuel cell stack and connect to external test leads or data acquisition modules. This structure allows for the acquisition of voltage, current, or equivalent electrical parameters of the corresponding single-cell structure without disassembling the fuel cell stack, used to identify single-layer performance degradation, contact abnormalities, partial short circuits, or abnormal gas distribution. The two lugs 100 can serve as the main connection terminal and the backup connection terminal, respectively, or can be alternately connected during long-term testing to reduce the impact of single-lead fatigue, oxidation, or poor contact on test reliability. This structure is particularly suitable for R&D testing, life evaluation, thermal cycling verification, and fuel cell stack fault diagnosis.

[0042] As a preferred embodiment of the above embodiments, refer to Figure 5 The single-cell structure has two open positioning notches 110 on its outer periphery. These notches 110 are used for clearance fitting with the fuel cell stack positioning posts (not shown in the attached diagram) required for forming the fuel cell stack. The two positioning notches 110 are respectively located on opposite sides of the single-cell structure. With this configuration, considering that the positioning holes corresponding to the traditional fuel cell stack positioning posts are located inside the single-cell structure, as the number of layers increases, hole position errors, plate warping, and sealing layer thickness deviations will continuously accumulate, causing jamming, friction, or localized compression between the positioning posts and the hole walls, leading to decreased assembly efficiency and additional mechanical stress input. Based on the above reasons, this invention provides open positioning notches 110 on the outer periphery of the single-cell structure for fitting with the fuel cell stack positioning posts; these positioning notches 110 are located at the outer periphery of the single-cell structure and do not penetrate the effective reaction zone, internal flow channel zone, or main sealing zone. The main difference between this structure and the traditional internally closed positioning holes is that the fuel cell stack positioning posts do not pass through the internal holes of the single-cell structure; the positioning notches 110 only guide and limit the fuel cell stack positioning posts, without creating closed over-constraints. An appropriate gap can be provided between the positioning notch 110 and the positioning post of the fuel cell stack to compensate for processing errors, micro-warping of the plates, differences in glass sealing layer thickness, and differences in thermal expansion. The technical effects of this structure include: 1) reducing the risk of positioning post jamming during multi-cell stacking; 2) reducing the occupation of the positioning structure by the internal flow channels, manifolds, and sealing paths; 3) reducing the additional mechanical stress applied to the metal-supported battery cells 10 and the sealing area during the positioning process; and 4) improving the fault tolerance of the fuel cell stack assembly and the efficiency of batch assembly.

[0043] Furthermore, the positioning notch 110 is provided in the edge or corner area of ​​the outer periphery of the single battery, and the number can be two, three, four or more; the shape of the notch can be semi-circular, U-shaped, arc-shaped, trapezoidal or other structures that can accommodate the positioning post and form an opening for guidance; this application does not specifically limit it.

[0044] The manufacturing steps of the present invention are described below with reference to the above embodiments: Step S1: Prepare a porous metal support; prepare a metal support according to the design porosity, thickness and size requirements, and perform edge pressing, compaction, rolling, molding, hot pressing or equivalent local densification treatment on its outer non-active area to form a low porosity or near-dense sealing edge.

[0045] Step S2: Independently prepare functional layers on the metal support; according to the SOFC single cell structure requirements, prepare the anode, electrolyte, cathode and necessary busbar layers on the porous metal support to obtain an independent metal-supported solar cell 10.

[0046] Step S3: Independently process the upper cover plate 30, flow channel plate 40 and lower cover plate 50 of the connector 20; the upper cover plate 30 forms a groove structure 301 for accommodating the metal support battery cell 10; the flow channel plate 40 forms a gas-side flow channel 80 and an air-side flow channel 90 on its upper and lower sides respectively, and forms corresponding internal manifolds, inlets and outlets and outer edge lugs 100; the lower cover plate 50 serves as a cover and support structure.

[0047] Step S4: An interlayer glass sealing layer 60 is formed between the upper cover plate 30 and the flow channel plate 40, and between the flow channel plate 40 and the lower cover plate 50. The interlayer glass sealing layer 60 can be formed by screen printing, scraping, dispensing, spraying, or laying prefabricated glass seals.

[0048] Step S5: Perform sealing heat treatment on the upper cover plate 30, flow channel plate 40 and lower cover plate 50 to form a continuous airtight interface in the interlayer glass sealing layer 60, thereby obtaining a low-deformation connector 20; the gas passage and air passage of the connector 20 are formed by the cooperation and sealing of the upper cover plate 30, flow channel plate 40 and lower cover plate 50.

[0049] Step S6: A glass sealing layer is provided at the corresponding position of the dense area 102 at the edge of the metal support cell 10 or the groove structure 301 of the upper cover plate 30; the glass sealing layer may be made of glass slurry, glass-ceramic slurry, prefabricated glass ring or composite sealing material.

[0050] Step S7: A flexible conductive buffer layer 70 is provided between the connector 20 and the conductive contact area of ​​the adjacent metal support cell 10 to compensate for flatness deviation and stabilize contact resistance.

[0051] Step S8: Embed the independently prepared metal support battery cell 10 into the groove structure 301 of the upper cover plate 30, so that a preset sealing gap is formed between the dense edge area 102 and the protrusion 3012 of the groove structure 301, and perform sealing heat treatment to achieve an airtight connection between the glass sealing layer and the metal support battery cell 10 and the upper cover plate 30.

[0052] Step S9: By using the peripheral opening positioning notch 110 to cooperate with the stack positioning post, the positioning and stacking of multiple single-cell repeating units are realized, and the lead ears 100 of each layer flow channel plate 40 are led out to the peripheral area of ​​the stack or the test terminal area.

[0053] This invention also discloses a metal-supported solid oxide fuel cell stack, comprising several single-cell structures according to any of the above embodiments, wherein the several single-cell structures are stacked. For the specific structure of the single-cell structure, please refer to the above embodiments. Since this metal-supported solid oxide fuel cell stack adopts all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated further here.

[0054] It should be noted that other aspects of the metal-supported solid oxide fuel cell single-cell structure disclosed in this invention are prior art and will not be repeated here.

[0055] The above are merely optional embodiments of the present invention and do not limit the patent scope of the present invention. Any application of the present invention directly or indirectly in other related technical fields is included within the patent protection scope of the present invention.

Claims

1. A single-cell structure for a metal-supported solid oxide fuel cell, characterized in that, The single-cell structure includes: Metal-supported solar cells (10); The connector (20) includes an upper cover plate (30), a flow channel plate (40), and a lower cover plate (50) arranged sequentially; the upper cover plate (30) is provided with a groove structure (301) for accommodating the metal support battery cell (10), and the metal support battery cell (10) is embedded in the groove structure (301); the flow channel plate (40) has a gas-side flow channel (80) and an air-side flow channel (90) respectively provided on its opposite sides; An interlayer glass sealing layer (60) is disposed between the upper cover plate (30) and the flow channel plate (40), and between the flow channel plate (40) and the lower cover plate (50) in the non-flow channel sealing area; the interlayer glass sealing layer (60) is used to seal and connect the upper cover plate (30), the flow channel plate (40) and the lower cover plate (50).

2. The single-cell structure as described in claim 1, characterized in that: The interlayer glass sealing layer (60) is formed by screen printing glass paste, scraping glass paste, applying adhesive glass paste, or prefabricating a glass sealing layer.

3. The single-cell structure as described in claim 1, characterized in that: The groove structure (301) includes a through groove (3011) and a stepped portion (3012) surrounding the through groove (3011); the metal-supported battery cell (10) includes a central active region (101) and an edge dense region (102) surrounding the central active region (101), the porosity of the edge dense region (102) being lower than that of the central active region (101); the central active region (101) is aligned with the through groove (3011), and the edge dense region (102) is mounted on the stepped portion (3012).

4. The single-cell structure as described in claim 3, characterized in that: A glass sealing layer is provided at the gap between the edge dense region (102) and the step portion (3012), and the glass sealing layer is used to seal the edge dense region (102) and the step portion (3012).

5. The single-cell structure as described in claim 3, characterized in that: The inner cavity of the through groove (3011) is provided with a flexible conductive buffer layer (70), and the flexible conductive buffer layer (70) is disposed between the central active region (101) and the connector (20); the flexible conductive buffer layer (70) is used to generate elastic or plastic deformation under the action of stacking preload and form multi-point contact with adjacent conductive surfaces.

6. The single-cell structure as described in claim 1, characterized in that: The connector (20) is provided with a through gas inlet (21) and a gas outlet (22), which are respectively located on opposite sides of the gas side flow channel (80); Specifically, the gas side flow channel (80) includes a disturbance flow channel region (801), a first intake manifold region (802) located on opposite sides of the disturbance flow channel region (801), and a first outlet manifold region (803). The first intake manifold region (802) is connected to the gas inlet (21), and the first outlet manifold region (803) is connected to the gas outlet (22). The disturbance flow channel region (801) includes a plurality of parallel disturbance flow channels (8011), each of which is wave-shaped. The structure can be wave-shaped, periodically deflected, or segmented tortuous; the first intake manifold region (802) and the first outlet manifold region (803) each include two equalizing chambers (8021) and several branch channels (8022). The two equalizing chambers (8021) are symmetrically arranged on opposite sides of the gas inlet (21) / gas outlet (22). One end of the branch channel (8022) is connected to the equalizing chamber (8021), and the other end of the branch channel (8022) is connected to the disturbance channel (8011).

7. The single-cell structure as described in claim 1, characterized in that: The connector (20) is provided with one or more air inlets (23) and one or more air outlets (24) that are disposed through the air inlet (23) and the air outlet (24) are respectively disposed on opposite sides of the air side channel (90); Specifically, the air side channel (90) includes a straight channel area (901), a second intake manifold area (902) located on opposite sides of the straight channel area (901), and a second exhaust manifold area (903). The second intake manifold area (902) is connected to the air inlet (23), and the second exhaust manifold area (903) is connected to the air outlet (24). The straight channel area (901) is provided with a plurality of parallel straight channels (9011), each of which is a straight line. The second intake manifold area (902) and the second exhaust manifold area (903) are each provided with a plurality of diverter elements (9021), which are arranged in a straight array along the arrangement direction of the plurality of straight channels (9011).

8. The single-cell structure as described in claim 1, characterized in that: The outer edge of the flow channel plate (40) is provided with two lugs (100), which are used to connect external test leads to monitor the electrical parameters of the corresponding single cell structure; wherein the two lugs (100) can be used as alternating connection ends or redundant connection ends.

9. The single-cell structure as described in claim 1, characterized in that: The outer periphery of the single cell structure is provided with at least two open positioning notches (110), which are used to fit with the stack positioning posts required for forming the fuel cell stack; at least two of the positioning notches (110) are respectively provided on opposite sides of the single cell structure.

10. A metal-supported solid oxide fuel cell stack, characterized in that: It includes several single-cell structures as described in any one of claims 1 to 9, wherein the several single-cell structures are stacked.

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