Stack tower of the cell stack and fuel cell

Abstract

The present invention discloses a stack tower of an electric stack and a fuel cell. The stack tower of the electric stack includes: an electric stack (100) formed with an anode gas port; a lower mica sheet (200) located below the electric stack (100); a gas distribution plate (300) located below the lower mica sheet (200) and having an upwardly convex anode sealing convex ring (400); the anode sealing convex ring (400) penetrates through the lower mica sheet (200) and is inserted into the anode gas port so as to radially seal the anode gas port. By inserting the anode sealing convex ring into the anode gas port to form an annular sealing surface, the anode gas cannot radially diffuse outward, realizing the primary sealing of the electric stack. By nesting a sealing layer outside the anode sealing convex ring, a secondary sealing is formed to ensure that the internal anode gas will not leak to the outside of the electric stack. The sealing performance of the anode of the electric stack is good, improving the fuel utilization rate and power generation efficiency, and ensuring the stability and safety of the fuel cell.

Description

Technical Field

[0001] The present invention belongs to the technical field of fuel cell power generation, and specifically relates to a stack tower of an electric stack and a fuel cell. Background Art

[0002] A solid oxide fuel cell is composed of an anode, a cathode, and an electrolyte. The anode is a fuel gas, and the cathode is air or an oxidizing gas containing air. Among them, the anode fuel gas is mostly supplied through a pipeline or a gas distribution plate, and the cathode gas is mostly in an open gas distribution mode. Since direct welding between the pipeline and the electric stack easily deforms the bottom plate of the electric stack, the stress generated by this deformation at high temperature can damage the sealing relationship between the battery chips, allowing the cathode gas to leak to the anode and oxidize the anode fuel gas. Therefore, ensuring the sealing of the anode of the electric stack is particularly important for both the single-stack test system and the stack tower.

[0003] A mica gasket is often placed at the interface between the pipeline or the gas distribution plate and the bottom plate of the electric stack, and a high-temperature adhesive is applied. Although this can improve the sealing situation to a certain extent, in actual application, due to the migration of the high-temperature adhesive at different temperatures, the sealing effect is not so ideal, affecting the stability of power generation performance and the accuracy of testing. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies of the prior art, the present invention provides a stack tower of an electric stack and a fuel cell. The anode of the electric stack in this stack tower has good sealing, improves fuel utilization rate and power generation efficiency, and ensures the stability and safety of the fuel cell.

[0005] To achieve the above object, according to one aspect of the present invention, there is provided a stack tower of an electric stack, which includes:

[0006] An electric stack, having an anode gas port formed therein;

[0007] A lower mica sheet, located below the electric stack;

[0008] A gas distribution plate, located below the lower mica sheet and having an upwardly convex anode sealing ring;

[0009] Wherein, the anode sealing ring penetrates through the lower mica sheet and is inserted into the anode gas port to radially seal the anode gas port. Sealing layers that are respectively in contact with the lower mica sheet are provided on at least part of the wall surfaces of the electric stack and the gas distribution plate, and the sealing layers are arranged around the outside of the anode sealing ring.

[0010] In some embodiments, the anode sealing boss is in a circular ring shape and includes a sealing ring gasket arranged along the stack height direction of the stack and an insulating boss for supporting the sealing ring gasket. The outer peripheral wall surface of the sealing ring gasket is in sealing fit with the inner peripheral wall surface of the anode gas port.

[0011] In some embodiments, the gas distribution plate includes a substrate and anode inlet branch channels and anode outlet branch channels spaced apart on the substrate. The anode inlet branch channels are used to accommodate the anode inlet branch pipes of the stack, and the anode outlet branch channels are used to accommodate the anode outlet branch pipes of the stack.

[0012] In some embodiments, the insulating boss is located on the substrate. The outlet end of the anode inlet branch pipe and the inlet end of the anode outlet branch pipe respectively penetrate through the insulating boss and extend into the sealing ring gasket. The sealing ring gasket makes the anode inlet branch pipe and the anode outlet branch pipe sealed radially; or, the outlet end of the anode inlet branch pipe and the inlet end of the anode outlet branch pipe are both formed as stepped pipe parts. The stepped pipe part includes the insulating boss located on the substrate integrally connected and an outlet pipe section extending into the sealing ring gasket. The sealing ring gasket makes the anode inlet branch pipe and the anode outlet branch pipe sealed radially.

[0013] In some embodiments, the sealing ring gasket is an octagonal metal ring gasket; and / or, the insulating boss is a high-temperature resistant insulating structural member.

[0014] In some embodiments, the lower mica sheet includes a mica end face disposed opposite to the stack or the gas distribution plate. The sealing layer is arranged in a closed surrounding manner along the outer peripheral edge of the mica end face.

[0015] In some embodiments, the sealing layer is a high-temperature adhesive.

[0016] In some embodiments, the stack tower includes one stack; or, the stack tower includes a plurality of stacks arranged along the stack height direction.

[0017] In some embodiments, the stack tower further includes a fastening assembly for fastening the stack. The fastening assembly includes:

[0018] Springs. Support ears are symmetrically arranged on the peripheral wall surface of the gas distribution plate. An upper mica sheet is arranged above the stack. In the stack height direction, a stack pressing plate is arranged on the top upper mica sheet. Each spring penetrates between each support ear and the stack pressing plate; and

[0019] Fixed seats. Two fixed seats are sleeved on each spring. The support ears and the stack pressing plate are both located between the two fixed seats.

[0020] In some embodiments, the elastic force of the spring gradually decreases from top to bottom along the stacking height direction.

[0021] In some embodiments, the stack tower of the fuel cell stack further includes an anode inlet main pipe section and an anode outlet main pipe section, and the anode inlet branch pipe and the anode outlet branch pipe are respectively connected beside the anode inlet main pipe section and the anode outlet main pipe section.

[0022] In some embodiments, in the stacking height direction, adjacent anode inlet main pipe sections and adjacent anode outlet main pipe sections are connected by bellows.

[0023] In addition, the present invention also provides a fuel cell, which includes the above-mentioned stack tower of the fuel cell stack.

[0024] In the stack tower of the fuel cell stack and the fuel cell of the present invention, the anode sealing convex ring is inserted into the anode gas port to form an annular sealing surface, so that the anode gas cannot diffuse radially outward, realizing the primary sealing of the fuel cell stack. By nesting the sealing layer outside the anode sealing convex ring, a secondary sealing is formed. In this way, it not only ensures that the anode gas inside will not leak to the outside of the fuel cell stack, but also prevents the external cathode gas from entering the gas distribution plate to oxidize the anode gas. The sealing performance of the anode of the fuel cell stack is good, improving the fuel utilization rate and power generation efficiency, and ensuring the stability and safety of the fuel cell.

[0025] Other features and advantages of the present invention will be described in detail in the subsequent specific implementation section. Brief Description of the Drawings

[0026] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present invention, but do not constitute a limitation to the present invention. In the drawings:

[0027] Figure 1 is a schematic structural diagram of a stack tower of a fuel cell stack according to a specific implementation of the present invention;

[0028] Figure 2 is Figure 1 a split structural diagram of, showing the gas distribution plate, upper mica sheet, fuel cell stack, lower mica sheet and gas distribution plate from top to bottom;

[0029] Figure 3 is Figure 2 a partial structural diagram of, showing the lower mica sheet and the gas distribution plate;

[0030] Figure 4 is Figure 2 a partial structural diagram of, showing the upper mica sheet, fuel cell stack, lower mica sheet and gas distribution plate;

[0031] Figure 5 isFigure 1 Schematic diagram of the local structure, showing the lower mica sheet and the sealing layer; and

[0032] Figure 6 Schematic diagram of the stack tower of the fuel cell stack according to the specific embodiment of the present invention, showing the stack tower structure with one fuel cell stack.

[0033] Description of the reference numerals:

[0034] 100 Fuel cell stack 200 Lower mica sheet

[0035] 300 Gas distribution plate 400 Anode sealing convex ring

[0036] 500 Sealing layer

[0037] 410 Sealing ring gasket 420 Insulating boss

[0038] 310 Substrate 320 Anode inlet branch channel

[0039] 330 Anode outlet branch channel

[0040] 1 Spring 2 Support ear

[0041] 3 Upper mica sheet 4 Fuel cell stack pressing plate

[0042] 5 Anode inlet main pipe section 6 Anode outlet main pipe section

[0043] 7 Bellows 8 Ceramic ring

[0044] 9 Anode inlet branch pipe extension seat 10 Anode outlet branch pipe extension seat

[0045] 11 Inlet mica hole 12 Outlet mica hole

[0046] 13 Spring hole 14 Fixed seat

[0047] H Stack height direction Specific embodiments

[0048] The following is a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0049] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0050] In the present invention, unless otherwise stated, the orientation terms such as "upper, lower, top, bottom" are usually used in the direction shown in the drawings or in the vertical, perpendicular or gravitational direction to describe the relative position relationship of the components.

[0051] The stack tower of the fuel cell and the fuel cell according to the present invention have good sealing performance of the anode of the stack, improving the fuel utilization rate and power generation efficiency, and ensuring the stability and safety of the fuel cell. The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0052] Due to the characteristics of high chemical energy efficiency and environmental friendliness of solid oxide fuel cells, they have broad application prospects. For small solid oxide fuel cell test systems or KW-level stack power generation systems, directly welding between the pipeline and the stack easily deforms the bottom plate of the stack. The stress generated by this deformation at high temperatures can damage the sealing relationship between the battery cells, allowing the cathode gas to leak to the anode and oxidize the anode fuel gas. Therefore, ensuring the sealing performance of the anode of the stack is particularly important for the stack tower.

[0053] In this system, the anode is ventilated through a pipeline, and the cathode is ventilated in an open manner. For the sealing performance of the stack tower, it mainly depends on two factors. One is the sealing structure, and the other is the pressing force between the stacks. To avoid anode oxidation caused by the leakage of cathode gas to the anode, the sealing performance of the anode of the stack tower is designed. The present invention provides a stack unit with a brand-new structure. Refer to Figures 1 to 6 In a specific embodiment, a stack tower, on the one hand, includes: a stack 100, a lower mica sheet 200, and a gas distribution plate 300;

[0054] Specifically, the stack 100 is formed with an anode gas port. The stack 100 is the core component of the solid oxide fuel cell and is used to convert chemical energy into electrical energy;

[0055] The lower mica sheet 200 is located below the stack 100. The lower mica sheet 200 has the functions of insulation and low-loss thermal resistance, which can block the heat transfer between the stacks 100 and reduce the sealing problems caused by stress generated by high temperatures;

[0056] The gas distribution plate 300 is located below the lower mica sheet 200 and has an upwardly convex anode sealing ring 400. The gas distribution plate 300 is attached to the lower mica sheet 200, and the stack 100 is ventilated through the gas distribution plate 300. Among them, the anode gas flows inside the anode sealing ring 400;

[0057] Among them, the anode sealing convex ring 400 penetrates through the lower mica sheet 200 and is inserted into the anode gas port to radially seal the anode gas port. Sealing layers 500 that are in contact with the lower mica sheet 200 are respectively provided on at least part of the wall surfaces of the fuel cell stack 100 and the gas distribution plate 300. The sealing layers 500 are arranged around the outside of the anode sealing convex ring 400. It can be understood that gas leakage is likely to occur at the pipeline interface. The anode sealing convex ring 400 is inserted into the anode gas port to form a fitting surface, which makes a sealing relationship between the anode sealing convex ring 400 and the anode gas port, that is, there is only an axial gas flow channel between the anode sealing convex ring 400 and the anode gas port, and there is no radial gas flow channel. In this way, it is ensured that the anode gas cannot leak along the anode gas port, guaranteeing the sealing of the anode gas. At the same time, the sealing layer 500 surrounds the outside of the anode sealing convex ring 400. In this way, a double-sealing structure is formed to further prevent the leakage of the anode gas outside the anode sealing convex ring 400.

[0058] Optionally, for the fuel cell stack 100, in a solid oxide fuel cell, there can be multiple fuel cell stacks 100, and the multiple fuel cell stacks 100 are stacked on top of each other to form a fuel cell stack tower. The fuel cell stack 100 includes a plurality of stacked cell sheets, an upper stack plate located at the top of the cell sheets, and a lower stack plate located at the bottom of the cell sheets. An anode gas port for ventilation is formed on the lower stack plate. The anode gas port includes a fuel cell stack anode inlet for introducing anode gas and a fuel cell stack anode outlet for discharging anode gas, so that the anode intake and anode exhaust can flow smoothly. For the number of fuel cell stacks 100, the size and shape of the anode gas port, they can be various and are not specifically limited herein.

[0059] Optionally, for the lower mica sheet 200, it can be in a sheet structure. Its shape can be a rectangle adapted to the fuel cell stack 100 to improve the integration and regularity of the fuel cell stack tower, or it can be a circle for easy processing. The thickness of the lower mica sheet 200 can be 1 mm to 2 mm to play an insulating role. In addition, it can be integral or spliced in parts, and is not specifically limited herein.

[0060] Optionally, for the gas distribution plate 300, it can be a plate-like structure with an anode gas distribution groove. At this time, the anode intake and anode exhaust are separated from each other. In this way, the upper wall surface of the gas distribution plate 300 can be flat, reducing the distance between the lower mica sheet 200 and the gas distribution plate 300, reducing the thickness of the sealing layer 500, and saving costs; the gas distribution plate 300 can also be a box-shaped plate body with an inner cavity structure, and it has a partition inside to separate the anode intake and anode exhaust.

[0061] Optionally, for the anode sealing convex ring 400, it can be a split structure, and the anode sealing convex ring 400 can be directly fixedly installed on the gas distribution plate 300 and can be embedded in the gas distribution plate 300, which is not specifically limited herein.

[0062] The inner part of the anode sealing boss 400 needs to insert the anode gas branch pipe of the fuel cell stack 100, and its outer part needs to be sealed with the anode gas port. In order to improve the sealing performance between the anode sealing boss 400 and the anode gas port, in one embodiment, the anode sealing boss 400 is in a circular ring shape and includes a sealing gasket 410 arranged along the stack height direction H of the fuel cell stack 100 and an insulating boss 420 for supporting the sealing gasket 410. The outer peripheral wall surface of the sealing gasket 410 is in sealing fit with the inner peripheral wall surface of the anode gas port, as Figure 2 and Figure 3 shown. Among them, the anode sealing boss 400 is a split structure. The insulating boss 420 sleeved on the anode gas branch pipe can be fixedly installed on the gas distribution plate 300 or stacked on the gas distribution plate 300. The insulating boss 420 supports the sealing gasket 410, and the insulating boss 420 is clamped between the sealing gasket 410 and the gas distribution plate 300 to play an insulating role.

[0063] Regarding the installation method between the insulating boss 420 and the sealing gasket 410, the installation method between the insulating boss 420 and the sealing gasket 410 can be a groove-block installation method. For example, a boss groove can be formed on the upper surface of the insulating boss 420, and the lower end of the sealing gasket 410 can be embedded in the boss groove. In this way, both the supporting force for the sealing gasket 410 can be ensured, and the sealing performance between the insulating boss 420 and the sealing gasket 410 can be improved. An intake mica hole 11 and an exhaust mica hole 12 for inserting the sealing gasket 410 are formed on the lower mica sheet 200. The upper end of the sealing gasket 410 passes through the intake mica hole 11 or the exhaust mica hole 12 and is inserted into the anode gas port. Such a plugging relationship enables the outer peripheral wall surface of the sealing gasket 410 to be in contact with the inner peripheral wall surface of the anode gas port and form an annular sealing surface. The annular sealing surface wraps around the outside of the anode gas, preventing the anode gas from diffusing radially outward, thereby achieving the primary sealing of the fuel cell stack 100.

[0064] The anode gas is introduced into the fuel cell stack 100 more uniformly and stably through the gas distribution plate 300. In one embodiment, the gas distribution plate 300 includes a substrate 310 and anode intake branch channels 320 and anode exhaust branch channels 330 spaced apart on the substrate 310. The anode intake branch channels 320 are used to accommodate the anode intake branch pipes of the fuel cell stack 100, and the anode exhaust branch channels 330 are used to accommodate the anode exhaust branch pipes of the fuel cell stack 100, as Figure 3 and Figure 4At least two mutually spaced open slots may be provided on the plate surface of the gas distribution plate 300, one of which is the anode gas inlet branch channel 320 capable of accommodating the anode gas inlet branch pipe, and the other is the anode gas outlet branch channel 330 capable of accommodating the anode gas outlet branch pipe. In this way, it is convenient to install and distribute the anode gas inlet branch pipe and the anode gas outlet branch pipe, and the upper surface of the gas distribution plate 300 is flat, avoiding uneven force on the gas distribution plate 300 caused by the protrusion of the anode gas inlet branch pipe and the anode gas outlet branch pipe, and effectively protecting the anode gas inlet branch pipe and the anode gas outlet branch pipe.

[0065] For the anode gas inlet pipe and the anode gas outlet pipe, in one embodiment, the insulating boss 420 is located on the substrate 310, and the outlet end of the anode gas inlet branch pipe and the gas inlet end of the anode gas outlet branch pipe respectively penetrate the insulating boss 420 and extend into the sealing ring gasket 410, and the sealing ring gasket 410 makes the anode gas inlet branch pipe and the anode gas outlet branch pipe radially sealed. The anode gas inlet pipe and the anode gas outlet pipe can be L-shaped, that is, including an anode gas horizontal pipe section located in the gas distribution plate 300 and an anode gas vertical pipe section protruding upward, and the insulating boss 420 can be fixedly sleeved on the anode gas vertical pipe section, that is, the insulating boss 420 and the anode gas vertical pipe section are separate structures, and the port of the anode gas vertical pipe section can be 2-3 mm higher than the plane of the substrate 310 and located in the sealing ring gasket 410, so that an annular sealing surface is formed between the port of the anode gas vertical pipe section and the sealing ring gasket 410, further reducing gas leakage.

[0066] In another embodiment, the outlet end of the anode inlet branch pipe and the inlet end of the anode outlet branch pipe are both formed into a stepped pipe portion, and the stepped pipe portion includes an insulating boss 420 integrally connected and located on the substrate 310 and an outlet pipe section extending into the sealing ring gasket 410, and the sealing ring gasket 410 makes the anode inlet branch pipe and the anode outlet branch pipe radially sealed. The diameter of the insulating boss 420 is larger than the diameter of the outlet pipe section to form a stepped structure, and the anode inlet pipe and the anode outlet pipe can be L-shaped, including an anode gas horizontal pipe section located in the gas distribution plate 300 and an anode gas vertical pipe section protruding upward. It can be understood that at this time, the insulating boss 420 and the anode gas vertical pipe section are an integral structure, and the outlet pipe section as the open end of the anode gas vertical pipe section can be 2-3 mm higher than the plane of the substrate 310 and located in the sealing ring gasket 410, so that an annular sealing surface is formed between the port of the anode gas vertical pipe section and the sealing ring gasket 410, further reducing gas leakage.

[0067] Further, regarding the structure of the sealing ring gasket 410, in one embodiment, the sealing ring gasket 410 is an octagonal metal ring gasket; and / or the insulating boss 420 is a high temperature resistant insulating structural member. Figure 2 and Figure 3As shown, the octagonal metal ring gasket is a solid metal gasket with an octagonal cross-section shape, which is made of metal materials through forging, heat treatment and machining. It is used in working conditions with temperature fluctuations, has a radial self-tightening sealing effect, and can withstand high temperature, high pressure, and has a durable and reliable seal. On the other hand, since the operating temperature of the fuel cell can reach as high as 600 to 800 °C, and insulation treatment needs to be carried out between the sealing ring gasket 410 and the gas distribution plate 300, the insulating boss 420 needs to have the dual characteristics of high temperature resistance and insulation. Therefore, the insulating boss 420 can be made of high-temperature mica materials, ceramic materials or vermiculite materials, such as mica rings, which are not specifically limited here.

[0068] In order to improve the sealing performance of each layer of the bracket, in one embodiment, the lower mica sheet 200 includes a mica end face disposed opposite to the fuel cell stack 100 or the gas distribution plate 300, and the sealing layer 500 is arranged in a closed manner around the outer periphery of the mica end face, as Figure 1 and Figure 5 shown. The sealing layer 500 is in a closed shape and can be rectangular or annular. A spacing of 1-2 mm can be formed between the lower mica sheet 200 and the fuel cell stack 100 or the gas distribution plate 300 for coating the sealing layer 500. The sealing layer 500 is nested outside the anode sealing convex ring 400 to form a secondary seal. In this way, it not only ensures that the anode gas inside will not leak outside the fuel cell stack 100, but also prevents the external cathode gas from entering the gas distribution plate 300 to oxidize the anode gas, improving the fuel utilization rate and power generation efficiency.

[0069] Since the fuel cell stack 100 is in a high-temperature state during operation, in one embodiment, the sealing layer 500 is a high-temperature adhesive. Generally, the high-temperature adhesive can withstand temperatures from 200 °C to 1800 °C, and can maintain good bonding performance and corrosion resistance at high temperatures, is easy to use and has a long service life.

[0070] In order to improve the applicability of the sealed fuel cell stack, in one embodiment, the fuel cell stack tower includes a fuel cell stack 100, as Figure 4 and Figure 6 shown. The single fuel cell stack 100 can be used in a small solid oxide fuel cell test system to ensure the airtightness of the anode gas, and can provide support and guarantee for obtaining more accurate data for the test system; or, in one embodiment, the fuel cell stack tower includes a plurality of fuel cell stacks 100 arranged along the stack height direction H, which can be used in a KW-level fuel cell power generation system to ensure the airtightness of the anode gas, and can ensure the safety of the fuel cell stack 100 and the stability of the power generation performance. In addition, each fuel cell stack 100, the lower mica sheet 200 and the gas distribution plate 300 at the bottom, and the upper mica sheet 3 at the top together form a unit body, and multiple unit bodies are stacked on top of each other to form a fuel cell stack tower with multiple fuel cell stacks 100.

[0071] On the other hand, during the operation of the stack tower of the fuel cell stack, since it is a high-temperature environment, the fuel cell stack 100 will expand. The lower fuel cell stack 100 has a relatively large pressure, and its own expansion is inhibited to a certain extent. For the upper fuel cell stack 100, its pressure is much smaller than that of the lower fuel cell stack 100, and the expansion will be more obvious. In the expanded state, the sealing effect between the fuel cell stacks 100 will inevitably change, and there is a risk of anode gas leakage.

[0072] Therefore, in one embodiment, the stack tower of the fuel cell stack further includes a fastening assembly for fastening the fuel cell stack 100. The fastening assembly includes: a spring 1, two lugs 2 are symmetrically arranged on the peripheral wall surface of the gas distribution plate 300, an upper mica sheet 3 is arranged above the fuel cell stack 100, and a stack pressing plate 4 is arranged on the upper mica sheet 3 at the top in the stack height direction H. A spring 1 is arranged through between each lug 2 and the stack pressing plate 4; and fixing seats 14, two fixing seats 14 are sleeved on each spring 1, and the lugs 2 and the stack pressing plate 4 are both located between the two fixing seats 14. As Figure 2 and Figure 6 shown, a spring hole 13 is arranged on the lug 2 of the gas distribution plate 300, the spring 1 passes through the spring hole 13, and the stack pressing plate 4 of the stack tower of the fuel cell stack is connected to each gas distribution plate 300 through the spring 1, and a certain pre-tightening force is given to the fuel cell stack 100 during high-temperature expansion, so that the expansion amount of the upper fuel cell stack is reduced, which ensures the sealing effect between the fuel cell stacks to a certain extent. Moreover, the springs 1 are symmetrically arranged on both sides of the fuel cell stack 100, making the acting force on the fuel cell stack 100 more balanced. The fixing seats 14 are arranged at the upper part of the stack pressing plate 4 and the lower part of the gas distribution plate 300 at the bottom, and there is a gap between the fixing seats 14 and the stack pressing plate 4 and the gas distribution plate 300, and the fixing seats 14 can limit the stack pressing plate 4 and the gas distribution plate 300 to a certain extent to prevent them from falling off the spring 1.

[0073] Furthermore, for the stack tower of multiple fuel cell stacks 100, during actual operation, the higher the fuel cell stack 100 is located, the greater the possibility of leakage, and the lower the probability of leakage of the fuel cell stack 100 at the lower layer of the stack tower. The main reason is that for fuel cell stacks 100 with the same strength, the pressing force of the lower fuel cell stack 100 is relatively high. If the same pressing force is applied to the upper fuel cell stack 100, it may exceed the mechanical strength that the lower fuel cell stack 100 can bear. In order to reduce the difference in the pressing force between the fuel cell stacks 100, in one embodiment, the elastic force of the spring 1 gradually decreases from top to bottom along the stack height direction H. The elastic force of the upper end of the spring 1 is relatively large, and the elastic force of the lower end of the spring 1 is relatively small. In this way, the pressing force between the fuel cell stacks 100 will be closer, the sealing effect between the fuel cell stacks 100 will be closer, and the distribution of the anode gas will also be more uniform.

[0074] For the transmission pipeline of the anode gas, in one embodiment, the stack tower of the fuel cell stack further includes an anode inlet main pipe section 5 and an anode outlet main pipe section 6. The anode inlet branch pipe and the anode outlet branch pipe are respectively connected beside the anode inlet main pipe section 5 and the anode outlet main pipe section 6, as Figure 1 and Figure 3 shown. An anode inlet branch pipe extension seat 9 and an anode outlet branch pipe extension seat 10 are arranged on the gas distribution plate 300. The anode inlet branch pipe is located in the anode inlet branch pipe extension seat 9 and is communicated with the anode inlet main pipe section 5, and the anode outlet branch pipe is located in the anode outlet branch pipe extension seat 10 and is communicated with the anode outlet main pipe section 6.

[0075] Furthermore, in one embodiment, in the stack height direction H, adjacent anode inlet main pipe sections 5 and adjacent anode outlet main pipe sections 6 are connected by bellows 7. The anode inlet main pipe section 5 and the anode outlet main pipe section 6 of each fuel cell stack 100 are communicated through the bellows 7 to form an anode gas main pipe extending along the stack height direction H outside the fuel cell stack. The bellows 7 can buffer the expansion of the pipeline airway at high temperatures. Taking the anode inlet main pipe section 5 as an example, there can be two or more bellows 7 between adjacent anode inlet main pipe sections 5, and the adjacent bellows 7 can be insulated from each other through a ceramic ring 8 and can radially seal the bellows 7.

[0076] In addition, the present invention also provides a fuel cell. The fuel cell includes the above-mentioned stack tower of the fuel cell stack. The fuel cell can be a small solid oxide fuel cell test system or a KW-level fuel cell stack power generation system. On the one hand, the sealing ring gasket 410 is inserted into the anode gas port to form an annular sealing surface, so that the anode gas cannot diffuse radially outward, realizing the primary seal of the fuel cell stack 100. The sealing layer 500 is nested outside the anode sealing convex ring 400 to form a secondary seal. In this way, it not only ensures that the anode gas inside will not leak to the outside of the fuel cell stack 100, but also prevents the external cathode gas from entering the gas distribution plate 300 to oxidize the anode gas, improving the fuel utilization rate and power generation efficiency. On the other hand, a pre-tightening force is provided to the fuel cell stack 100 through a spring to reduce the expansion amount of the upper fuel cell stack 100, further ensuring the sealing effect between the fuel cell stacks.

[0077] In summary, the stack tower of the fuel cell stack and the fuel cell have good sealing performance of the anode of the fuel cell stack, improving the fuel utilization rate and power generation efficiency, and ensuring the stability and safety of the fuel cell.

[0078] It should be specifically noted that the other components and functions of the stack tower of the fuel cell stack and the fuel cell according to the embodiments of the present invention are known to those of ordinary skill in the art. To reduce redundancy, they are not described herein.

[0079] The preferred embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention. For example, changes in the shape, thickness, and material of the end plate sealing layer. These simple modifications all fall within the protection scope of the present invention.

[0080] In addition, it should be noted that in the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. Without contradiction, they can be combined in any suitable way. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0081] Furthermore, any combination can be made between various different embodiments of the present invention as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. Stack tower of a fuel cell stack, characterized in that The stack tower of the fuel cell stack includes: A fuel cell stack (100) formed with an anode gas port; A lower mica sheet (200) located below the fuel cell stack (100); A gas distribution plate (300) located below the lower mica sheet (200) and having an upwardly protruding anode sealing convex ring (400); Wherein, the anode sealing convex ring (400) penetrates through the lower mica sheet (200) and is inserted into the anode gas port to radially seal the anode gas port. A sealing layer (500) that fits against the lower mica sheet (200) is respectively provided on at least part of the wall surfaces of the fuel cell stack (100) and the gas distribution plate (300), and the sealing layer (500) is arranged around the outside of the anode sealing convex ring (400); The anode sealing convex ring (400) is annular and includes a sealing ring gasket (410) arranged along the stack height direction (H) of the fuel cell stack (100) and an insulating boss (420) for supporting the sealing ring gasket (410). The outer peripheral wall surface of the sealing ring gasket (410) is in sealing contact with the inner peripheral wall surface of the anode gas port; The lower mica sheet (200) includes a mica end face opposite to the fuel cell stack (100) or the gas distribution plate (300). A gap of 1-2 mm is formed between the lower mica sheet (200) and the fuel cell stack (100) or the gas distribution plate (300) to enclose and arrange the sealing layer (500) along the outer periphery of the mica end face.

2. The stack tower of the fuel cell stack according to claim 1, characterized in that, The gas distribution plate (300) includes a substrate (310), an anode inlet branch channel (320) and an anode outlet branch channel (330) spaced apart on the substrate (310). The anode inlet branch channel (320) is used to accommodate the anode inlet branch pipe of the fuel cell stack (100), and the anode outlet branch channel (330) is used to accommodate the anode outlet branch pipe of the fuel cell stack (100).

3. The stack tower of the fuel cell stack according to claim 2, wherein, The insulating boss (420) is located on the substrate (310). The outlet end of the anode inlet branch pipe and the inlet end of the anode outlet branch pipe respectively penetrate through the insulating boss (420) and extend into the sealing ring gasket (410), and the sealing ring gasket (410) radially seals the anode inlet branch pipe and the anode outlet branch pipe; or, the outlet end of the anode inlet branch pipe and the inlet end of the anode outlet branch pipe are both formed as stepped pipe parts. The stepped pipe part includes the insulating boss (420) located on the substrate (310) integrally connected and an outlet pipe section extending into the sealing ring gasket (410), and the sealing ring gasket (410) radially seals the anode inlet branch pipe and the anode outlet branch pipe.

4. The stack tower of the fuel cell stack according to claim 2, characterized in that, The sealing ring gasket (410) is an octagonal metal ring gasket; and / or, the insulating boss (420) is a high-temperature resistant insulating structural member.

5. The cell stack tower according to claim 1, characterized in that, The sealing layer (500) is a high-temperature adhesive.

6. The stack tower of the fuel cell stack according to claim 1, characterized in that, The stack tower of the fuel cell stack includes one fuel cell stack (100); or, the stack tower of the fuel cell stack includes a plurality of fuel cell stacks (100) arranged along the stack height direction (H).

7. The stack tower of the fuel cell stack according to claim 6, characterized in that, The stack tower of the fuel cell stack further includes a fastening assembly for fastening the fuel cell stack (100). The fastening assembly includes: A spring (1), support lugs (2) are symmetrically arranged on the peripheral wall surface of the gas distribution plate (300), an upper mica sheet (3) is arranged above the stack (100), and a stack pressing plate (4) is arranged on the upper mica sheet (3) at the top in the stack height direction (H). The spring (1) penetrates between each support lug (2) and the stack pressing plate (4); and A fixing seat (14), two fixing seats (14) are sleeved on each spring (1), and the support lugs (2) and the stack pressing plate (4) are both located between the two fixing seats (14).

8. The stack tower of the fuel cell stack according to claim 7, wherein The elastic force of the spring (1) gradually decreases from top to bottom in the stack height direction (H).

9. The stack tower of the fuel cell stack according to claim 2, wherein, The stack tower of the fuel cell further includes an anode inlet main pipe section (5) and an anode outlet main pipe section (6), and the anode inlet branch pipe and the anode outlet branch pipe are respectively connected beside the anode inlet main pipe section (5) and the anode outlet main pipe section (6).

10. The stack tower of the fuel cell stack according to claim 9, characterized in that, In the stack height direction (H), adjacent anode inlet main pipe sections (5) and adjacent anode outlet main pipe sections (6) are connected by bellows (7).

11. A fuel cell, characterized in that, The fuel cell includes the stack tower of the fuel cell according to any one of claims 1 to 10.

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