Connecting piece for combined solid oxide fuel cell

Abstract

The invention discloses a connecting piece for a combined solid oxide fuel cell, which comprises a first support frame, a second support frame and a connecting main body, the first support frame and the second support frame are oppositely arranged up and down and are both hollow frame structures, and the connecting main body is located between the first support frame and the second support frame. The connecting main body, the first supporting frame and the second supporting frame are connected into a whole and then are mounted in the fuel cell, the connecting main body is provided with upper convex parts and lower convex parts, the plurality of upper convex parts are uniformly arranged at intervals along the length direction of the connecting main body, and the plurality of lower convex parts are uniformly arranged at intervals along the length direction of the connecting main body; the multiple upper protruding parts and the multiple lower protruding parts are arranged in a staggered mode, the thickness of the connecting piece is reduced on the premise that the performance is guaranteed through the precise plastic forming capacity of the stamping technology, and meanwhile cost reduction and performance optimization are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of fuel cells, in particular to a connector for a combined solid oxide fuel cell. Background Art

[0002] In solid oxide fuel cells, connectors play a key role in isolating fuel and air, building gas flow channels, and collecting current. Traditional connectors such as Figure 3 As shown, it is mainly made by powder metallurgy or etching forming process, and the fuel channel and the air channel are formed at the top and the bottom respectively, which has obvious disadvantages. First, due to the process requirements to ensure structural strength and air tightness, the thickness of the connector is generally about 2 mm, the material utilization rate is low and the weight is large, resulting in material waste and increasing its own cost. Secondly, powder metallurgy needs to go through multiple steps such as mixing powder, pressing, and sintering, with high energy consumption and low yield. The etching process has serious material waste, large equipment investment and environmental pollution problems. The above problems restrict the large-scale application of SOFC. The present invention specifically proposes a combined connector structure and stamping forming process to solve the core pain points in the prior art. Summary of the invention

[0003] In order to solve the above technical problems, the present invention relates to a connector for a combined solid oxide fuel cell, which has a simple and reliable structure, effectively solves the above technical problems, and is suitable for popularization and use. In order to achieve the above purpose, the present invention is implemented by the following technical solutions:

[0004] A connector for a combined solid oxide fuel cell comprises a first support frame, a second support frame and a connecting body, wherein the first support frame and the second support frame are arranged opposite to each other up and down and are both hollow frame structures, the connecting body is located between the first support frame and the second support frame, and the connecting body is connected to the first support frame and the second support frame as a whole and then installed in the fuel cell, the connecting body is provided with an upper protrusion and a lower protrusion, a plurality of the upper protrusions are evenly spaced along the length direction of the connecting body, a plurality of the lower protrusions are evenly spaced along the length direction of the connecting body, and a plurality of the upper protrusions and a plurality of the lower protrusions are staggered with each other.

[0005] On the basis of the above scheme and as a preferred scheme of the above scheme: the first support frame and the second support frame are both rectangular frame structures, and the first support frame and the second support frame are connected to the connecting body by laser welding, brazing or glass melting welding and cover the circumferential side edges.

[0006] On the basis of the above solution and as a preferred solution of the above solution: a flat plate transition portion is further provided between the adjacent upper protrusions and lower protrusions, and the surface of the flat plate transition portion is coplanar with the base plate of the connection body.

[0007] On the basis of the above solution and as a preferred solution of the above solution: the upper raised portion and the lower raised portion are both manufactured by stamping.

[0008] On the basis of the above scheme and as a preferred scheme of the above scheme: the upper raised portion and the lower raised portion are both isosceles trapezoidal structures.

[0009] Compared with the prior art, the present invention has the following outstanding and beneficial technical effects: through the precision plastic forming capability of the stamping process, combined with the functional decoupling and local reinforcement design of the split structure, the thickness of the connector is reduced from the traditional 2mm to 0.1-0.5mm while ensuring performance, while achieving cost reduction and performance optimization. This technical path provides an industrializable solution for lightweight and low-cost SOFC connectors. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of connecting the main body assembly;

[0011] Figure 2 is a schematic diagram of a first support frame;

[0012] Figure 3 This is a schematic diagram of existing connections. DETAILED DESCRIPTION

[0013] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments. However, the specific implementation methods and embodiments described below are for illustrative purposes only and are not intended to limit the present invention.

[0014] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate directions or positional relationships based on the attached Figure 1 The directions or positional relationships shown are only for the convenience of describing the present invention, and are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0015] In the description of this application, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0016] In order to solve the above technical problems, Figure 1-2As shown, the present invention designs a connector for a combined solid oxide fuel cell, including a first support frame 1, a second support frame 2, and a connecting body 3. The first support frame 1 and the second support frame 2 are arranged opposite to each other up and down, and the connecting body 3 is located between the first support frame 1 and the second support frame 2. The first support frame 1 and the second support frame 2 are both rectangular frame structures and cover the peripheral edges of the connecting body 3. The thickness of the connecting body 3 can be as thin as 0.1mm-0.5mm. The surface of the connecting body 3 is punched by a stamping die to form a plurality of upper protrusions 4 and lower protrusions 5. The plurality of upper protrusions 4 are evenly spaced along the length direction of the connecting body 3, and the plurality of lower protrusions 5 are evenly spaced along the length direction of the connecting body 3. The plurality of upper protrusions 4 and the plurality of lower protrusions 5 are staggered with each other, and corresponding air flow channels and fuel channels are formed below the upper protrusions 4 and above the lower protrusions 5.

[0017] Since metal powder needs to be pressed and sintered to form a dense structure during powder metallurgy, if the thickness is too thin, the powder fluidity is poor, which can easily lead to uneven density or sintering deformation, and it is difficult to ensure strength and air tightness. If an etching process is used to remove materials through chemical corrosion to form a structure, penetration or edge collapse is likely to occur during etching of the thin plate, and the thickness usually needs to be ≥2mm to maintain processing stability. In the present invention, a split design is used to split the overall structure into multiple functional components. The flow channel of the connecting body 3 can be formed by stamping a protruding portion to avoid thickness redundancy caused by functional integration of the one-piece structure, directly plastically deform the plate, and accurately control the material flow through the mold. There is no need to rely on powder filling or chemical corrosion, and ultra-thin components can be stably formed. Therefore, the thickness of the connecting body 3 can be controlled between 0.1mm-0.5mm, and the utilization rate of the plate material in the stamping process can reach more than 90%. Compared with the original thickness of at least 2mm, the material consumption is greatly reduced, and the material cost is reduced by more than 60%. The high material efficiency makes the ultra-thin design industrially feasible, avoiding being forced to increase the thickness due to cost constraints.

[0018] The support frame only bears the functions of mechanical support and current collection. The local strength can be improved by stamping reinforcement ribs or frame structure. The connection body 3 is dedicated to forming a gas flow channel. During assembly, the connection body 3 is placed between the two support frames, and continuous sealing welding is performed along the edge of the frame by laser welding. The welding temperature is controlled at 800-1000℃ to form an integral structure. The assembled connector is installed on the fuel cell stack. The raised part forms a gas flow channel. The support frame provides mechanical support and current collection functions. The weld area is locally thickened. While ensuring the overall airtightness, the thickness of the non-welding area can be extremely thinned.

[0019] In another preferred embodiment, glass melting welding can be used instead of laser welding. Low-melting-point glass powder is pre-coated on the contact surface between the support frame and the connecting body 3, heated to 600°C to melt the glass, and airtight packaging is achieved after cooling. This solution is suitable for scenarios with higher requirements for high-temperature tolerance.

[0020] It is further preferred in the present embodiment that a flat transition portion 6 is further provided between the adjacent upper protrusions 4 and the lower protrusions 5. The flat transition portion 6, as a straight area between adjacent protrusions, can eliminate local vortices formed in traditional continuous corrugated flow channels due to sudden corner changes, so that the gas can smoothly transition along the flow channel. In addition, the alternating layout of the flat transition portion 6 and the protrusions forms a "corrugated plate"-like structure, which disperses mechanical stress through periodic changes in geometric shapes, thereby significantly improving the bending stiffness of the thin plate and meeting the anti-deformation requirements under the pressure of battery stack assembly.

[0021] It is further preferred in the present embodiment that the upper raised portion 4 and the lower raised portion 5 are both isosceles trapezoidal structures. The inclination angle of the slope of the isosceles trapezoid guides the gas to flow in a specific direction, forming a laminar-dominated flow state, which increases the contact time between the fuel and the electrode and improves the sufficiency of the electrochemical reaction. In addition, the gas coverage rate of the isosceles trapezoidal flow channel is significantly higher than that of the rectangular or semicircular flow channel, thereby improving the maximum power density of the single cell. Moreover, the symmetrical structure of the isosceles trapezoid enables the material to flow evenly during the stamping process, avoiding thickness reduction or rupture caused by unilateral stretching, thereby improving the yield rate and enhancing the compressive strength.

[0022] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made by technicians in the relevant technical field based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A connector for a combined solid oxide fuel cell, characterized in that: The invention comprises a first support frame, a second support frame and a connection body, wherein the first support frame and the second support frame are arranged opposite to each other up and down and are both hollow frame structures, the connection body is located between the first support frame and the second support frame, and the connection body is connected with the first support frame and the second support frame as a whole and then installed in a fuel cell, the connection body is provided with an upper protrusion and a lower protrusion, a plurality of the upper protrusions are evenly spaced along the length direction of the connection body, a plurality of the lower protrusions are evenly spaced along the length direction of the connection body, and a plurality of the upper protrusions and a plurality of the lower protrusions are staggered with each other.

2. A connector for a combined solid oxide fuel cell according to claim 1, characterized in that: The first support frame and the second support frame are both rectangular frame structures. The first support frame and the second support frame are connected to the connection body by laser welding, brazing or glass melting welding and cover the peripheral side edges.

3. The connector for a combined solid oxide fuel cell according to claim 1, characterized in that: A flat plate transition portion is also provided between the adjacent upper protrusions and lower protrusions, and the surface of the flat plate transition portion is coplanar with the base plate of the connection body.

4. The connector for a combined solid oxide fuel cell according to claim 1, characterized in that: The upper raised portion and the lower raised portion are both manufactured by stamping.

5. The connector for a combined solid oxide fuel cell according to claim 1, characterized in that: The upper convex portion and the lower convex portion are both in an isosceles trapezoidal structure.

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