A sealed structure, a flat-plate RSOC stack and its preparation method

Abstract

This invention provides a sealing structure, a planar RSOC stack, and a method for its fabrication. The sealing structure includes a sealing body with multiple pores and a rigid material layer. The rigid material layer completely covers the upper and lower sides of the sealing body, and each pore is completely filled with the rigid material layer. The sealing body is made of Fe-16Cr alloy, and the rigid material layer comprises an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3. This invention combines the high-temperature structural support of the foamed metal Fe-16Cr alloy with the excellent sealing performance of the amorphous glass system, which can simultaneously achieve a low gas leakage rate and a high-temperature structural support function of the sealing structure. The amorphous glass system can provide effective interfacial sealing through sufficient deformation, thereby reducing the probability of high-temperature sealing failure, and is particularly suitable for interlayer sealing of planar RSOC stacks.

Description

Technical Field

[0001] This invention relates to the field of reversible solid oxide battery technology, and in particular to a sealed structure, a planar RSOC stack, and a method for its preparation. Background Technology

[0002] Reversible Solid Oxide Cells (RSOCs), as electrochemical conversion devices, can convert chemical energy into electrical energy not only in fuel cell mode but also in electrolyzer mode. The successful application of this technology is of great significance in alleviating the energy crisis, protecting the environment, and ensuring my country's energy security. The fuel cell stack is the core working unit of the RSOC system, composed of RSOC single cells connected in series. Among them, planar RSOCs have significant commercial potential due to their high power density and low manufacturing cost. High-temperature sealing is a major bottleneck restricting the development of fuel cell stack technology. The fuel cell stack is composed of repeated units (single cells / sealing materials / metal connectors) stacked together.

[0003] Sealing materials are a crucial component of fuel cell stacks. Their primary function is to isolate fuel gas and oxidizing gases, preventing performance degradation or even explosions caused by gas mixing, while also providing insulation between different components. However, existing high-temperature sealing materials struggle to simultaneously meet both performance and structural requirements.

[0004] Therefore, there is an urgent need in the field for a sealing structure that can simultaneously achieve both airtightness and structural support, so as to ensure that the flat-plate RSOC stack can have a stable interface seal and maintain a stable structure during operation. Summary of the Invention

[0005] The purpose of this invention is to provide a sealed structure, a planar RSOC stack, and a method for preparing the same, thereby solving the technical problem that the planar RSOC stack cannot operate stably due to the failure of the sealing material in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention first provides a sealing structure, including a sealing body with multiple pores and a rigid material layer, wherein the rigid material layer completely covers the upper and lower sides of the sealing body, and each pore is completely filled with the rigid material layer.

[0007] The sealing body is made of Fe-16Cr alloy, and the rigid material layer consists of an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3.

[0008] Preferably, in the sealing body: the porosity is 60% to 80%, the pore size is 0.1 to 1 mm, the wire diameter is 0.05 to 0.1 mm, and the thickness is 0.3 to 0.5 mm.

[0009] Preferably, the amorphous glass system is composed of: 60-65 wt% SiO2, 15-20 wt% TiO2, 10-15 wt% Na2O, 5-10 wt% K2O and Al2O3, wherein the mass fraction of Al2O3 is greater than 0 and less than or equal to 5 wt%.

[0010] Preferably, the glass softening temperature of the amorphous glass system is 600~700℃, and the median particle size of the amorphous glass powder in the amorphous glass system is 3~20μm.

[0011] Preferably, the coefficient of thermal expansion of both the sealing body and the amorphous glass system is (10~12)×10. -6 / K.

[0012] Accordingly, the present invention also provides a planar RSOC stack, which is composed of multiple repeating units stacked together. Each repeating unit includes a metal connector, a sealing structure as described above, and a single cell stacked sequentially from bottom to top.

[0013] Accordingly, the present invention also provides a method for preparing the above-mentioned planar RSOC stack, the method comprising:

[0014] S10, mechanically mix amorphous glass powder with organic solvent to obtain amorphous glass slurry. The amorphous glass powder is an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3.

[0015] S20, by pumping, the amorphous glass slurry completely covers the upper and lower sides of the sealing body and fills the multiple pores of the sealing body to obtain the prepared sealing material.

[0016] S30, the metal connector, the pre-sealing material and the single cell are stacked in sequence to form a pre-repeating unit, and multiple pre-repeating units are assembled to form a pre-pile;

[0017] S40 involves heating and pressurizing the prepared fuel cell stack to obtain a fuel cell stack with a sealed structure.

[0018] Preferably, in step S10, the content of amorphous glass powder in the amorphous glass slurry is 50~70wt%.

[0019] Preferably, in step S10: the organic solvent is terpineol with added ethyl cellulose, and the content of ethyl cellulose in the organic solvent is 3~4 wt%.

[0020] Preferably, in the heating and pressurization process of step S40: the heating temperature is 800~850℃, the heating rate is 2~10℃ / min, the pressurization pressure is 0.05~0.2MPa, and the time is 1~3h.

[0021] The beneficial effects of this invention are as follows: Unlike existing technologies, this invention provides a sealing structure, a planar RSOC stack, and a method for its fabrication. The sealing structure includes a sealing body with multiple pores and a rigid material layer. The rigid material layer completely covers the upper and lower sides of the sealing body, and each pore is completely filled with the rigid material layer. The sealing body is made of Fe-16Cr alloy, and the rigid material layer comprises an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3. The sealing structure provided by this invention combines the high-temperature structural support of the foamed metal Fe-16Cr alloy with the excellent sealing performance of the amorphous glass system, achieving both a low gas leakage rate and high-temperature structural support. The amorphous glass system, through sufficient deformation, provides effective interfacial sealing, thereby reducing the probability of high-temperature seal failure. This is particularly suitable for interlayer sealing in planar RSOC stacks, thus ensuring the long-term stable operation of the planar RSOC stack. Attached Figure Description

[0022] Figure 1 Schematic diagrams of the sealing structure provided in the embodiments of the present invention at 20°C and 750°C;

[0023] Figure 2 This is a schematic diagram of the sealing body in the sealing structure provided in the embodiment of the present invention;

[0024] Figure 3 This is a flowchart of the preparation method of the planar RSOC stack provided in the embodiment of the present invention;

[0025] Figure 4 This is the thermal expansion curve of the rigid material layer in the sealing structure provided in Embodiment 1 of the present invention;

[0026] Figure 5 This is a curve showing the change in the wetting angle of H-5 glass on Fe-16Cr alloy and a schematic diagram of high-temperature deformation in the sealing structure provided in Embodiment 1 of the present invention;

[0027] Figure 6 This refers to the air leakage rate of H-5 glass in the sealing structure provided in Embodiment 1 of the present invention during 5 cycles of heating and cooling.

[0028] In the diagram, 10 – metal connector; 20 – sealing structure; 21 – sealing body; 30 – single cell. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0031] Currently, sealing materials used in planar RSOC stacks can be categorized into compression sealing materials, flexible sealing materials, and rigid material layers. Compression sealing materials, represented by ceramic-based materials, require significant external pressure to achieve a seal, and generally suffer from high leakage rates. Flexible sealing materials, primarily based on precious metals, are costly to manufacture and have complex processing techniques. Rigid material layers can achieve effective interfacial sealing with adjacent components through chemical bonding and adhesion, and are inexpensive and easy to manufacture.

[0032] Glass is a common rigid material layer, and based on its crystallization tendency, it can be divided into microcrystalline glass and amorphous glass. Microcrystalline glass has many advantages, such as low leakage rate, and the crystalline phase in the glass matrix can act as a skeleton to maintain the supporting structure of the sealing material. However, uncontrollable crystallization can occur during heat treatment. The precipitated crystalline phase may change the thermal properties of the sealing material, such as the coefficient of thermal expansion, affecting its own stability and the stability of its bonding with adjacent components.

[0033] Therefore, amorphous glass, with its excellent sealing performance and chemical stability, has become a research focus. It can provide effective interfacial sealing through sufficient deformation and also exhibits good chemical compatibility with adjacent components, laying the foundation for long-term stable performance of the fuel cell stack. However, the significant deformation of amorphous glass during the sealing process can easily cause structural instability in the fuel cell stack, posing a new problem to be solved. Existing high-temperature sealing materials are insufficient to simultaneously meet the requirements for functional characteristics and structural support. Therefore, there is an urgent need in this field to develop novel sealing materials and structures that simultaneously achieve low leakage rates and high-temperature structural support to ensure the long-term stable operation of the fuel cell stack.

[0034] In view of this, the present invention first provides a sealing structure 20 suitable for the interlayer of a planar RSOC battery stack, which combines a foam metal Fe-16Cr alloy with high-temperature structural support with an amorphous glass system with excellent sealing performance. This achieves low gas leakage rate, high-temperature structural support, and deformation under specific pressure, thereby reducing the probability of high-temperature sealing failure. It is particularly suitable for interlayer sealing of planar reversible solid oxide battery stacks.

[0035] Please see Figure 1 , Figure 1 The diagram shows the structure of the sealing structure 20 provided in the embodiment of the present invention at 20°C and 750°C. The sealing structure 20 includes a sealing body 21 with multiple pores and a rigid material layer. The rigid material layer completely covers the upper and lower sides of the sealing body 21, and each pore is completely filled with the rigid material layer.

[0036] The sealing body 21 is made of Fe-16Cr alloy, and the rigid material layer includes an amorphous glass system (H-5 glass) composed of SiO2-TiO2-Na2O-K2O-Al2O3. The Fe-16Cr alloy material of the sealing body 21 can support the sealing structure 20. The amorphous glass system of the rigid material layer can not only provide effective interface sealing through sufficient deformation, but also has good chemical compatibility with adjacent components, which will lay the foundation for achieving long-term stable performance of the fuel cell stack.

[0037] Specifically, the upper and lower sides of the sealing body 21 are covered with a complete rigid material layer, thereby ensuring that the high-temperature insulation of the sealing structure 20 meets the requirements.

[0038] For details, please continue reading Figure 1 When the sealing structure 20 is at 20°C, the rigid material layer does not deform; when the sealing structure 20 is at 750°C, the rigid material layer begins to deform.

[0039] Please see Figure 2 , Figure 2 This is a schematic diagram of the sealing body 21 in the sealing structure 20 provided in this embodiment of the invention. In the sealing body 21, the porosity is 60%–80%, the pore diameter is 0.1–1 mm, the wire diameter is 0.05–0.1 mm, and the thickness is 0.3–0.5 mm. The higher porosity facilitates the doping of a sufficient amount of amorphous glass system, while the smaller pore and wire diameters may help improve the sealing accuracy and stability. The selection of a suitable thickness for the sealing body 21 is likely a comprehensive result considering factors such as material cost and structural strength while ensuring the sealing effect.

[0040] Specifically, the rigid material layer is a high-temperature thermally stable amorphous glass. The composition of the amorphous glass system is: 60~65wt% SiO2, 15-20wt% TiO2, 10~15wt% Na2O, 5~10wt% K2O, and Al2O3, with the mass fraction of Al2O3 being greater than 0 and less than or equal to 5wt%. Among them, SiO2 provides good chemical stability and mechanical strength for the amorphous glass system; TiO2 helps improve certain physical properties of amorphous glass, such as refractive index; Na2O can reduce the melting temperature and viscosity of amorphous glass to a certain extent, which is helpful for processing; K2O, similar to Na2O, can also regulate the properties of amorphous glass; the content of Al2O3 is greater than 0 and less than or equal to 5wt%, although the content is small, it may affect the structure and properties of amorphous glass, such as improving the chemical corrosion resistance of amorphous glass.

[0041] Specifically, the glass softening temperature of the amorphous glass system is 600~700℃, and the median particle size of the amorphous glass powder in the amorphous glass system is 3~20μm.

[0042] Specifically, the coefficients of thermal expansion of both the sealing body 21 and the amorphous glass system are (10~12)×10. -6 / K; where the coefficient of thermal expansion represents the degree to which a material expands or contracts in size when the temperature changes. When the coefficients of thermal expansion of the sealing body 21 and the amorphous glass system are matched, they can expand and contract at similar rates in environments with changing temperatures, thereby reducing internal stress and potential damage caused by differences in thermal expansion and contraction.

[0043] Accordingly, please continue reading Figure 1 The present invention also provides a planar RSOC stack, which is composed of multiple repeating units stacked together. Each repeating unit includes a metal connector 10, a sealing structure 20 as described above, and a single cell 30 stacked sequentially from bottom to top.

[0044] Please see Figures 1 to 3 , Figure 3 This is a flowchart illustrating the fabrication method of a planar RSOC stack provided in an embodiment of the present invention; wherein, the above-mentioned fabrication method specifically includes:

[0045] S10, the amorphous glass powder is mechanically mixed with an organic solvent to obtain an amorphous glass slurry. The amorphous glass powder is an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3.

[0046] Specifically, step S10 also includes:

[0047] First, an amorphous glass powder is provided, which is H-5 glass, and is an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3;

[0048] Next, the amorphous glass powder and organic solvent are mechanically mixed in a high-energy ball mill at a speed of 300~400 r / min to obtain an amorphous glass slurry.

[0049] Specifically, the amorphous glass slurry contains 50-70 wt% amorphous glass powder; the organic solvent is terpineol with added ethyl cellulose, and the content of ethyl cellulose in the organic solvent is 3-4 wt%; the appropriate terpineol content can ensure that the amorphous glass slurry has good filling properties and stability during the molding process; the addition of ethyl cellulose helps to improve the viscosity and stability of the organic solvent, thereby improving the overall performance of the amorphous glass slurry.

[0050] S20, the amorphous glass slurry is completely covered on the upper and lower sides of the sealing body 21 and filled in the multiple pores of the sealing body 21 by pumping, thus obtaining the prepared sealing material.

[0051] Specifically, step S20 also includes:

[0052] The amorphous glass slurry is completely covered on the upper and lower sides of the sealing body 21 and filled into multiple pores of the sealing body 21 by pumping, thus obtaining a pre-sealing material; wherein the upper and lower sides of the sealing body 21 are covered with a complete rigid material layer, thereby ensuring that the high-temperature insulation of the sealing structure 20 meets the requirements.

[0053] S30, the metal connector 10, the pre-sealing material and the single cell 30 are stacked in sequence to form a pre-repeating unit, and multiple pre-repeating units are assembled to form a pre-charge stack.

[0054] Specifically, step S30 also includes:

[0055] The metal connector 10, the pre-sealing material, and the single cell 30 are stacked sequentially to form a pre-repeating unit, and multiple pre-repeating units are assembled in a stacking manner to form a pre-charge stack.

[0056] S40, the prepared fuel cell stack is heated and pressurized to obtain a fuel cell stack with a sealed structure 20.

[0057] Specifically, step S40 also includes:

[0058] The prepared fuel cell stack is simultaneously heated and pressurized. The amorphous glass slurry in the prepared sealing material deforms under heat to provide sufficient interfacial sealing. During operation, it can block leakage channels through the viscous flow of the amorphous glass system to achieve self-healing. At the same time, the reduction in the thickness of the amorphous glass system during the sealing process can reduce the accumulated thermal stress at the interface (the interface between the prepared sealing material and the metal connector 10 or the single cell 30), avoid cracks at the interface that lead to sealing failure, thereby significantly improving the adhesion strength of the interface, and finally obtaining a fuel cell stack with a sealing structure 20.

[0059] Furthermore, during the heating and pressurization process: the heating temperature is 800~850℃, the heating rate is 2~10℃ / min, the pressurization pressure is 0.05~0.2MPa, and the time is 1~3h.

[0060] The higher heating temperature ensures that the temperature of the amorphous glass slurry is higher than the glass softening temperature, making the amorphous glass slurry more prone to deformation and flow; the lower heating rate allows organic matter to volatilize slowly, reducing the generation of air leakage holes in the sealing structure 20.

[0061] Furthermore, the pressurization direction is perpendicular to the upper and lower sides of the sealing body 21. The large loading pressure (0.05~0.2MPa) can ensure that the interfaces of the sealing structure 20 in contact with the metal connector 10 and the single battery 30 are effectively connected.

[0062] Specifically, during the heating and pressurization process, the organic matter in the amorphous glass slurry is burned and volatilized, the glass softens, flows, sintersects and becomes dense, and achieves interfacial sealing with adjacent components. The Fe-16Cr foam metal alloy undergoes a certain degree of deformation due to the pressure state and the high-temperature softening of the H-5 glass, which will provide high-temperature structural support for the seal.

[0063] Specifically, the sealing mechanism of the aforementioned planar RSOC stack is as follows: When the pre-sealing material is under high temperature and pressure, the Fe-16Cr foam alloy exhibits elastic properties to a certain extent. At a loading pressure of 0.05~0.2MPa, the deformation of the Fe-16Cr alloy satisfies the interface connection requirements between the single cell 30 and the metal connector 10, thereby effectively reducing the interface contact resistance. H-5 glass, in a high-temperature molten state, fills the voids and the upper and lower surfaces of the Fe-16Cr alloy. At operating temperatures of 650℃ to 800℃, it deforms along with the Fe-16Cr alloy. Given that the coefficient of thermal expansion of the H5 glass is similar to that of the Fe-16Cr alloy, neither will experience thermal stress concentration due to temperature changes.

[0064] The technical solution of this application will now be described in conjunction with specific embodiments.

[0065] Example 1:

[0066] Embodiment 1 of the present invention first proposes a sealing structure 20, which includes a sealing body 21 with multiple pores and a rigid material layer. The rigid material layer completely covers the upper and lower sides of the sealing body 21, and each pore is completely filled with the rigid material layer.

[0067] The sealing body 21 is made of Fe-16Cr alloy, and the rigid material layer includes an amorphous glass system (H-5 glass) composed of SiO2-TiO2-Na2O-K2O-Al2O3.

[0068] Specifically, the Fe-16Cr alloy has a porosity of 80%, a pore size of 6 mm, a wire diameter of 0.2 mm, and a thickness of 0.35 mm.

[0069] Specifically, the mass fractions of SiO2, TiO2, Na2O, K2O, and Al2O3 in the H-5 glass with the rigid material layer are 64wt%, 18wt%, 10wt%, 7wt%, and 1wt%, respectively; the softening temperature of the H-5 glass is 610℃; the median particle size of the H-5 amorphous glass powder is 15μm; and the coefficient of thermal expansion of the H-5 glass is 11.0×10⁻⁶. -6 / K.

[0070] Accordingly, Embodiment 1 of the present invention also provides a planar RSOC stack, which is composed of multiple repeating units stacked together. Each repeating unit includes a metal connector 10, a sealing structure 20 as described above, and a single cell 30 stacked sequentially from bottom to top.

[0071] Accordingly, Embodiment 1 of the present invention also provides a method for preparing a planar RSOC stack, the method comprising:

[0072] First, H-5 amorphous glass powder and organic solvent are mechanically mixed in a high-energy ball mill at a speed of 350 r / min to obtain an amorphous glass slurry; wherein, the content of H-5 amorphous glass powder in the amorphous glass slurry is 60 wt%; the organic solvent is terpineol with added ethyl cellulose, and the content of ethyl cellulose in the organic solvent is 3 wt%.

[0073] Secondly, the amorphous glass slurry is completely covered on the upper and lower sides of the sealing body 21 and filled into multiple pores of the sealing body 21 by pumping, thus obtaining the prepared sealing material.

[0074] Next, the metal connector 10, the pre-sealing material, and the single cell 30 are stacked in sequence to form a pre-repeating unit, and multiple pre-repeating units are assembled in a stacking manner to form a pre-charge stack.

[0075] Finally, the prepared fuel cell stack is heated and pressurized to obtain a fuel cell stack with a sealed structure 20. During the heating and pressurization process, the heating temperature is 850℃, the heating rate is 2℃ / min, the pressurization pressure is 0.1MPa, and the time is 2h.

[0076] Furthermore, the performance of the fuel cell stack with sealed structure 20 prepared in Example 1 was tested:

[0077] Please see Figure 4 , Figure 4 This is the thermal expansion curve of the rigid material layer in the sealing structure 20 provided in Embodiment 1 of the present invention; wherein, by Figure 4 It can be seen that the glass transition temperature (Tg) of the H-5 glass provided in Embodiment 1 of the present invention is 566℃, the glass softening temperature (Ts) of the H-5 glass is 593℃, and the coefficient of thermal expansion (CTE) of the H-5 glass is 11.04 × 10⁻⁶. -6 / K.

[0078] Please see Figure 5 , Figure 5 This is a curve showing the change in wetting angle of H-5 glass on Fe-16Cr alloy and a schematic diagram of high-temperature deformation in the sealing structure 20 provided in Embodiment 1 of the present invention; specifically, the wetting process of H-5 glass on the Fe-16Cr alloy substrate with temperature was tested, and the test results are shown in [reference missing]. Figure 5 As shown: H-5 glass powder was pressed under a loading pressure of 12MPa for 2 minutes to obtain glass cylinders with a diameter of 10mm and a height of 5mm; then the glass cylinders were placed on a sheet metal substrate of 50×50×1mm and placed together in a tube furnace for heating treatment at a heating rate of 5℃ / min from 700 to 950℃.

[0079] Please continue reading. Figure 5 Schematic diagram of high temperature deformation ( Figure 5 (Lower left), which shows that H-5 glass powder exhibits good wettability on the Fe-16Cr alloy metal substrate. The molten glass at 900℃ can effectively wet the metal connector 10 to form a good bonding interface.

[0080] Furthermore, the airtightness of the aforementioned sealing structure 20 was tested as follows:

[0081] Specifically, the airtightness test principle of the aforementioned sealing structure 20 is as follows: disassemble the flat-plate RSOC stack to obtain the sealing structure 20, apply a certain loading pressure of 0.15MPa to the sealing structure 20 and the Fe-16Cr alloy fixture, and the sealing structure 20, the Fe-16Cr alloy fixture, the leak gas test flow meter, and the incoming gas flow meter together constitute a sealed space; then, heat the Fe-16Cr alloy fixture and the sealing structure 20 to 750℃, and under a gas pressure of 13.8~20.7kPa, once the sealing structure 20 leaks gas, the leak gas test flow meter will display the leakage amount, and the gas leakage rate at high temperature can be measured.

[0082] Specifically, the preparation process of the sealing structure 20 is as follows: the prepared cast tape is cut into a U-shaped frame with an outer frame of 70mm×70mm and an inner frame of 50mm×50mm; an adhesive is applied to the U-shaped frame, and it is placed in an Fe-16Cr alloy fixture to ensure a tight bond between the sealing structure 20 and the Fe-16Cr alloy fixture; subsequently, the airtightness of the sealing structure 20 under different ventilation pressures is tested, and the same sealing structure 20 is tested multiple times to ensure the accuracy and reliability of the data.

[0083] Please see Figure 6 , Figure 6 This refers to the leakage rate of the H-5 glass in the sealing structure 20 provided in Embodiment 1 of the present invention during five thermal cycles. Figure 6 It can be seen that the leakage rate of H-5 glass is consistently below 0.004 sccm / cm, and the gas leakage rate shows a slight decreasing trend with the increase of the number of cold and hot cycles, demonstrating good sealing performance.

[0084] Compared with the prior art, the present invention has the following advantages:

[0085] First, the SiO2-TiO2-Na2O-K2O-Al2O3 amorphous glass system in the sealing structure 20, which is in direct contact with the adjacent components of the fuel cell stack, can maintain its amorphous structure at the operating temperature of the fuel cell stack and has excellent long-term high-temperature stability. This allows the contact angle between the glass and the metal connector 10 to be less than 90°, thereby ensuring good interface sealing during the sealing process and achieving a low gas leakage rate in the sealing structure 20.

[0086] Secondly, during the heating and pressurization process, the organic matter in the amorphous glass slurry is burned and volatilized, the glass softens, flows, sintersects and becomes dense, and achieves interface sealing with adjacent components. The Fe-16Cr foam metal alloy undergoes a certain degree of deformation due to the pressure state and the high temperature softening of H-5 glass, which will provide high-temperature structural support for the seal.

[0087] In summary, unlike existing technologies, this invention provides a sealing structure 20, a planar RSOC stack, and a method for its fabrication. The sealing structure 20 includes a sealing body 21 with multiple pores and a rigid material layer. The rigid material layer completely covers the upper and lower sides of the sealing body 21, and each pore is completely filled with the rigid material layer. The sealing body 21 is made of Fe-16Cr alloy, and the rigid material layer comprises an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3. The sealing structure 20 provided by this invention combines the high-temperature structural support of the foamed metal Fe-16Cr alloy with the excellent sealing performance of the amorphous glass system. This combination achieves both a low gas leakage rate and high-temperature structural support in the sealing structure 20. The amorphous glass system, through sufficient deformation, provides effective interfacial sealing, thereby reducing the probability of high-temperature sealing failure. This is particularly suitable for interlayer sealing in planar RSOC stacks, thus ensuring the long-term stable operation of planar RSOC stacks.

[0088] It should be noted that all the above embodiments belong to the same inventive concept, and the descriptions of each embodiment have different focuses. Where the description in a particular embodiment is not detailed, please refer to the description in other embodiments.

[0089] The above embodiments merely illustrate implementation methods of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A sealing structure, characterized in that, It includes a sealing body with multiple pores and a rigid material layer, the rigid material layer completely covering the upper and lower sides of the sealing body, and each pore is completely filled with the rigid material layer; The sealing body is made of Fe-16Cr alloy, and the rigid material layer comprises an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3. The porosity of the sealing body is 60% to 80%, the pore size is 0.1 to 1 mm, the wire diameter is 0.05 to 0.1 mm, and the thickness is 0.3 to 0.5 mm.

2. The sealing structure according to claim 1, characterized in that, The amorphous glass system is composed of 60-65 wt% SiO2, 15-20 wt% TiO2, 10-15 wt% Na2O, 5-10 wt% K2O and Al2O3, with the mass fraction of Al2O3 being greater than 0 and less than or equal to 5 wt%.

3. The sealing structure according to claim 1, characterized in that, The glass softening temperature of the amorphous glass system is 600~700℃, and the median particle size of the amorphous glass powder in the amorphous glass system is 3~20μm.

4. The sealing structure according to claim 1, characterized in that, The coefficient of thermal expansion of both the sealing body and the amorphous glass system is (10~12)×10. -6 / K.

5. A planar RSOC stack, characterized in that, The planar RSOC stack is composed of multiple repeating units stacked together. Each repeating unit includes a metal connector, a sealing structure as described in any one of claims 1 to 4, and a single cell, which are stacked sequentially from bottom to top.

6. A method for preparing a planar RSOC stack as described in claim 5, characterized in that, The method includes: S10, the amorphous glass powder is mechanically mixed with an organic solvent to obtain an amorphous glass slurry, wherein the amorphous glass powder is an amorphous glass system composed of SiO2-TiO2-Na2O-K2O-Al2O3; S20, the amorphous glass slurry is completely covered on the upper and lower sides of the sealing body and filled into multiple pores of the sealing body by pumping to obtain a pre-sealing material; S30, the metal connector, the pre-sealing material and the single cell are stacked sequentially to form a pre-repeating unit, and multiple pre-repeating units are assembled to form a pre-charge stack; S40, the prepared fuel cell stack is heated and pressurized to obtain the fuel cell stack with the sealed structure.

7. The method for preparing a planar RSOC stack according to claim 6, characterized in that, In step S10: the content of amorphous glass powder in the amorphous glass slurry is 50~70wt%.

8. The method for preparing a planar RSOC stack according to claim 6, characterized in that, In step S10: the organic solvent is terpineol with added ethyl cellulose, and the content of ethyl cellulose in the organic solvent is 3~4 wt%.

9. The method for preparing a planar RSOC stack according to claim 6, characterized in that, In the heating and pressurization process of step S40: the heating temperature is 800~850℃, the heating rate is 2-10℃ / min, the pressurization pressure is 0.05~0.2MPa, and the time is 1~3h.

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