Crystalline sealing glass powder and preparation method thereof, sealing glass and metal-supported solid oxide fuel cell

Abstract

The invention discloses crystalline sealing glass powder and a preparation method thereof, sealing glass and a metal-supported solid oxide fuel cell, and relates to the technical field of vehicles. The catalyst is applied to a metal-supported solid oxide fuel cell and comprises SiO2, B2O3, Al2O3, ZnO, a light rare earth oxide and an alkaline earth metal oxide. By adding the light rare earth oxide, the volatilization of boron in the glass can be effectively inhibited, the generation of holes in the sealing glass is reduced, the air tightness of the sealing glass is improved, and meanwhile, by adding the alkaline earth metal oxide and the light rare earth oxide, the expansion coefficient and the characteristic temperature can be effectively adjusted, so that the sealing flowability is better, and the expansion coefficient is higher; the glass has an expansion coefficient and a working temperature which are matched with the sealing requirement of a solid fuel cell. The crystallization type sealing glass powder is crystallized in the sealing process, and the thermal expansion coefficient of the crystallization type sealing glass powder is matched with the thermal expansion coefficient of other assemblies of the SOFC.

Description

Technical Field

[0001] This application relates to the field of new energy technologies, and particularly to crystalline sealing glass powder, a preparation method thereof, sealing glass, and a metal-supported solid oxide fuel cell. Background Art

[0002] The sealing glass of SOFC (metal-supported solid oxide fuel cell) mainly includes four major systems: silicate sealing glass, borosilicate sealing glass, aluminosilicate sealing glass, and boronoaluminosilicate sealing glass. Among them, silicon borate has become the most potential sealing glass variety. However, in the operating environment of SOFC, due to the volatilization of boron-containing substances in the borosilicate glass sealing material, the thermal stability of the glass itself is severely reduced. At the same time, the volatilization of boron-containing substances will also cause a large number of pores to be generated in the sealing glass, affecting the airtightness of the sealing material.

[0003] Traditional glass is amorphous and is a mixture of various components, making the SOFC stack sealed with traditional glass very prone to damage due to the severe expansion of the sealing glass. Summary of the Invention

[0004] This application provides a crystalline sealing glass powder, a preparation method thereof, sealing glass, and a metal-supported solid oxide fuel cell to solve the problems of volatilization of existing boron-containing substances and severe expansion of the sealing glass.

[0005] In a first aspect, this application provides a crystalline sealing glass powder for use in a metal-supported solid oxide fuel cell, and its composition includes: SiO2, B2O3, Al2O3, ZnO, light rare earth oxides, and alkaline earth metal oxides.

[0006] Glass-ceramics is a new type of glass. Its principle is to adjust the components so that crystal nuclei are spontaneously formed inside the glass, and then a glass crystal with relatively uniform components is formed. Glass-ceramics usually combines the characteristics of glass and ceramics, and its coefficient of thermal expansion changes linearly. In this application, the crystalline sealing glass powder includes: SiO2, B2O3, Al2O3, ZnO, light rare earth oxides, and alkaline earth metal oxides, and can form glass-ceramics.

[0007] In this application, adding light rare earth oxides can effectively inhibit the volatilization of boron in the glass, reduce the generation of pores in the sealing glass, and improve the airtightness of the sealing glass. At the same time, adding alkaline earth metal oxides and light rare earth oxides can effectively adjust the coefficient of thermal expansion and characteristic temperature, making the sealing fluidity better and the coefficient of thermal expansion higher, so that the glass has a coefficient of thermal expansion and working temperature that match the sealing requirements of the solid fuel cell. The crystalline sealing glass powder of this application crystallizes during the sealing process and matches the coefficient of thermal expansion of other components of the SOFC.

[0008] Light rare earths are a group of elements composed of seven rare earth elements: lanthanum, cerium, praseodymium, neodymium, promethium, samarium, and europium. Light rare earth elements have relatively active chemical properties and can react with many elements. They easily combine with oxygen to form stable oxides, such as lanthanum oxide (La2O3), cerium oxide (CeO2), etc., and have good chemical stability.

[0009] In some embodiments, the light rare earth oxide includes at least one of La2O3, CeO2, and Nd2O3. By using at least one of the above light rare earth oxides, the volatilization of boron in the glass can be inhibited, and the strength and chemical stability of the glass can be improved.

[0010] In some embodiments, the alkaline earth metal oxide includes at least one of MgO, CaO, SrO, and BaO. By using at least one of the above alkaline earth metal oxides, the melting temperature and viscosity of the glass can be reduced, and the characteristic temperature and expansion coefficient of the glass can be adjusted.

[0011] In some embodiments, the mass ratio of SiO2, B2O3, Al2O3, ZnO, light rare earth oxide, and alkaline earth metal oxide is (5~15):(10~15):(1~8):(5~10):(30~45):(10~30). By controlling the mass ratio of each raw material, the expansion coefficient and working temperature of the encapsulation glass can be adjusted as needed, so that the softening temperature and sealing temperature of the encapsulation glass are as low as possible to reduce production energy consumption. At the same time, the sealing temperature of the encapsulation glass should be higher than the battery working temperature to avoid damaging the seal, and the softening temperature of the encapsulation glass should be as close as possible to the battery working temperature but slightly higher than the battery working temperature to avoid obvious morphological changes in the sealing glass during the operation of the battery stack.

[0012] In a second aspect, the present application provides a method for preparing a crystalline sealing glass powder, including the following steps: Mix the raw materials of the crystalline sealing glass powder to obtain a mixed material; Melt the mixed material to obtain a glass melt; Quench the glass melt to obtain glass; Crush the glass to obtain a crystalline sealing glass powder.

[0013] By mixing the raw materials of the glass powder to obtain a mixed material; melting the mixed material to obtain a glass melt; quenching the glass melt to obtain glass; crushing the glass to obtain a glass powder.

[0014] In some embodiments, in the step of melting the mixed material to obtain a glass melt: The melting temperature is 1400°C to 1600°C. Within this temperature range, a clear glass melt can be obtained; The heating rate during melting is 3℃ / min to 8℃ / min. When the heating rate during melting is within this range, the decomposition and melting process of the glass batch can be stabilized, and the possibility of deflagration of the raw materials can be reduced.

[0015] The heat preservation time during melting is 0.5 to 2 hours. When the heat preservation time during melting is within this range, the decomposition and melting process of the glass batch can be stabilized, and the probability of deflagration of the raw materials can be reduced.

[0016] In some embodiments, when the glass liquid is quenched to obtain glass: The quenching method includes any one of water quenching or oil quenching. Quenching can cause the molten glass liquid to form crushed glass in a very short time. Using these quenching methods can achieve this purpose at a lower cost; and / or, The quenching temperature is 0℃ to 30℃. When the quenching temperature is within this range, the quenching of the glass liquid can be achieved under the condition of low-cost control.

[0017] In some embodiments, when the glass is crushed to obtain crystalline sealing glass powder: The method for preparing the glass powder includes any one of ball milling and jet milling. By finely grinding the glass slag, crystalline sealing glass powder can be obtained. Using the above-mentioned grinding methods, glass powder with a uniform particle size distribution can be obtained; The mesh number of the sieve through which the glass powder passes after being obtained is 100 to 350 meshes. By sieving, coarse particle glass powder can be removed. When the mesh number of the sieve is within this range, glass powder with a D50 particle size of 5 to 15 μm can be obtained. The mesh number of the sieve refers to the particle size or fineness of the material, and its definition is the number of holes per square inch. The mesh number of the sieve is inversely proportional to the pore size, that is, the higher the mesh number, the smaller the pore size on the sieve.

[0018] In a third aspect, the present application provides a sealing glass formed from the crystalline sealing glass powder of the first aspect, wherein: The softening temperature of the sealing glass is 650 to 700℃; and / or, The sealing temperature of the sealing glass is 830 to 860℃; and / or, The expansion coefficient of the sealing glass is 8.7 to 9.5×10 -6 / K.

[0019] In a fourth aspect, the present application provides a metal-supported solid oxide fuel cell including the sealing glass of the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0021] Figure 1 This is the coefficient of thermal expansion curve graph of borosilicate glass in the prior art of the present application.

[0022] Figure 2 This is the coefficient of thermal expansion curve graph of the crystalline sealing glass powder in Embodiment 1 of the present application.

[0023] Figure 3 This is the XRD measurement graph of the crystalline sealing glass powder in Embodiment 1 of the present application.

[0024] Figure 4 This is the physical picture of the encapsulated glass-ceramics prepared from the crystalline sealing glass powder in Embodiment 1 of the present application. Detailed implementation manners

[0025] To make the objectives, technical solutions and advantages of the present application clearer, the following will clearly and completely describe the technical solutions of the present application in conjunction with the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present application.

[0026] The sealing glass of SOFC (metal-supported solid oxide fuel cell) mainly has four major systems: silicate sealing glass, borosilicate sealing glass, aluminosilicate sealing glass, and borosilicate-aluminosilicate sealing glass. Among them, silicon borate has become the most potential sealing glass variety. However, in the operating environment of SOFC, the borosilicate glass sealing material will severely reduce the thermal stability of the glass itself due to the volatilization of boron-containing substances. At the same time, the volatilization of boron-containing substances will also cause a large number of pores to be generated in the sealing glass, affecting the airtightness of the sealing material.

[0027] Traditional glass is amorphous, that is, it is a mixture of various components, and its thermal expansion characteristics can be referred to Figure 1, which has a very prominent swelling peak, and the swelling peak is exactly within the operating range of medium and high temperature SOFCs (600 - 800 °C). Since the other components of the stack usually have a linear swelling mode, the SOFC stack sealed with traditional glass is very likely to be damaged due to the drastic swelling of the sealing glass. Glass-ceramics is a new type of glass. Its principle is to adjust the components so that crystal nuclei spontaneously form inside the glass, and then glass crystals with relatively uniform components are formed. Glass-ceramics usually combines the characteristics of glass and ceramics, and its coefficient of thermal expansion changes linearly. As Figure 2 shown, however, currently it is impossible to make the swelling effect of glass-ceramics similar to that of other metal components and ceramic components. At the same time, the softening temperature and sealing temperature should be as low as possible to reduce production energy consumption. At the same time, the sealing temperature should be higher than the operating temperature to avoid damaging the seal, and the softening temperature should be as close as possible to the operating temperature but slightly higher than the operating temperature. Avoid obvious morphological changes in the sealing glass during the operation of the battery stack, making the encapsulation of SOFCs full of challenges.

[0028] In view of this, the present application provides a crystalline sealing glass powder, its preparation method, a sealing glass and a metal-supported solid oxide fuel cell to solve the problems of volatilization of existing boron-containing substances and drastic swelling of the sealing glass.

[0029] In the first aspect, the present application provides a crystalline sealing glass powder applied to a metal-supported solid oxide fuel cell, and its composition includes: SiO2, B2O3, Al2O3, ZnO, light rare earth oxides and alkaline earth metal oxides.

[0030] Glass-ceramics is a new type of glass. Its principle is to adjust the components so that crystal nuclei spontaneously form inside the glass, and then glass crystals with relatively uniform components are formed. Glass-ceramics usually combines the characteristics of glass and ceramics, and its coefficient of thermal expansion changes linearly. The crystalline sealing glass powder of the present application includes: SiO2, B2O3, Al2O3, ZnO, light rare earth oxides and alkaline earth metal oxides, and can form glass-ceramics.

[0031] By adding light rare earth oxides, the present application can effectively inhibit the volatilization of boron in the glass, reduce the generation of pores in the sealing glass, and improve the airtightness of the sealing glass. At the same time, adding alkaline earth metal oxides and light rare earth oxides can effectively adjust the coefficient of thermal expansion and characteristic temperature, making the sealing fluidity better and the coefficient of thermal expansion higher, so that the glass has a coefficient of thermal expansion and operating temperature that match the sealing requirements of solid fuel cells. The crystalline sealing glass powder of the present application crystallizes during the sealing process and matches the coefficient of thermal expansion of other components of the SOFC.

[0032] Light rare earths are a group of elements composed of seven rare earth elements: lanthanum, cerium, praseodymium, neodymium, promethium, samarium, and europium. The chemical properties of light rare earth elements are relatively active and can react with many elements. They easily combine with oxygen to form stable oxides, such as lanthanum oxide (La2O3), cerium oxide (CeO2), etc., and have good chemical stability.

[0033] In combination with the first aspect, in some embodiments provided by the present application, the light rare earth oxide includes at least one of La2O3, CeO2, and Nd2O3. By using at least one of the above light rare earth oxides, the volatilization of boron in the glass can be inhibited, and the strength and chemical stability of the glass can be improved.

[0034] In combination with the first aspect, in some embodiments provided by the present application, the alkaline earth metal oxide includes at least one of MgO, CaO, SrO, and BaO. By using at least one of the above alkaline earth metal oxides, the melting temperature and viscosity of the glass can be reduced, and the characteristic temperature and expansion coefficient of the glass can be adjusted.

[0035] In combination with the first aspect, in some embodiments provided by the present application, the mass ratio of SiO2, B2O3, Al2O3, ZnO, light rare earth oxide, and alkaline earth metal oxide is (5~15):(10~15):(1~8):(5~10):(30~45):(10~30). By controlling the mass ratio of each raw material, the expansion coefficient and working temperature of the encapsulation glass can be adjusted as needed, so that the softening temperature and sealing temperature of the encapsulation glass are as low as possible to reduce production energy consumption. At the same time, the sealing temperature of the encapsulation glass should be higher than the battery working temperature to avoid damaging the seal, and the softening temperature of the encapsulation glass should be as close as possible to the battery working temperature but slightly higher than the battery working temperature to avoid obvious morphological changes in the sealing glass during the operation of the battery stack.

[0036] In the second aspect, the present application provides a preparation method of a crystalline sealing glass powder, including the following steps: Mix the raw materials of the crystalline sealing glass powder to obtain a mixed material; Melt the mixed material to obtain a glass liquid; Quench the glass liquid to obtain glass; Crush the glass to obtain a crystalline sealing glass powder.

[0037] By mixing the raw materials of the crystalline sealing glass powder to obtain a mixed material; melting the mixed material to obtain a glass liquid; quenching the glass liquid to obtain glass; crushing the glass to obtain a crystalline sealing glass powder.

[0038] It should be noted that the raw material of SiO2 can be SiO2, the raw material of B2O3 can be H3BO3, the raw material of Al2O3 can be Al(OH)3, the raw material of ZnO can be ZnO, the raw material of light rare earth oxides can be La2O3, CeO2, Nd2O3, and the raw material of alkaline earth metal oxides can be CaCO3, SrCO3, Mg(OH)2, BaCO3.

[0039] Combined with the first aspect, in some embodiments provided by the present application, in the step of melting the mixture to obtain the glass liquid: the melting temperature is 1400°C to 1600°C. When the melting temperature is within this range, a clear glass liquid can be obtained.

[0040] Combined with the first aspect, in some embodiments provided by the present application, in the step of melting the mixture to obtain the glass liquid: the heating rate during melting is 3°C / min to 8°C / min. When the heating rate during melting is within this range, the decomposition and melting process of the glass batch can be stabilized, and the possibility of deflagration of the raw materials can be reduced.

[0041] Combined with the first aspect, in some embodiments provided by the present application, in the step of melting the mixture to obtain the glass liquid: the heat preservation time during melting is 0.5 to 2 h. When the heat preservation time during melting is within this range, the decomposition and melting process of the glass batch can be stabilized, and the probability of deflagration of the raw materials can be reduced.

[0042] Combined with the first aspect, in some embodiments provided by the present application, in the step of quenching the glass liquid to obtain the glass: the quenching method includes any one of water quenching or oil quenching. Quenching can cause the molten glass liquid to form broken glass in a very short time. By using these quenching methods, this purpose can be achieved at a relatively low cost. The quenching temperature is 0°C to 30°C. When the quenching temperature is within this range, the quenching of the glass liquid can be realized under the condition of low-cost control.

[0043] Combined with the first aspect, in some embodiments provided by the present application, in the step of finely grinding the glass slag to obtain the crystalline sealing glass powder: the fine grinding method includes any one of ball milling and jet milling. By finely grinding the glass slag to obtain the crystalline sealing glass powder using the above-mentioned grinding methods, glass powder with a uniform particle size distribution can be obtained.

[0044] Combined with the first aspect, in some embodiments provided by the present application, in the step of pulverizing the glass to obtain the crystalline sealing glass powder: the mesh number of the sieve through which the pulverized glass passes is 100 to 350 meshes. By sieving, the coarse particle glass powder can be removed. When the mesh number of the sieve is within this range, glass powder with a D50 particle size of 5 to 15 μm can be obtained. The mesh number of the sieve refers to the particle size or fineness of the material, and its definition is the number of holes per square inch. The mesh number of the sieve is inversely proportional to the pore size, that is, the higher the mesh number, the smaller the pore size on the sieve.

[0045] In a third aspect, the present application provides a sealing glass formed from the crystalline sealing glass powder of the first aspect, wherein: the softening temperature of the sealing glass is 650 - 700 °C; and / or, the sealing temperature of the sealing glass is 830 - 860 °C; and / or, the coefficient of thermal expansion of the sealing glass is 8.7 - 9.5×10 -6 / K.

[0046] In a fourth aspect, the present application provides a metal-supported solid oxide fuel cell including the sealing glass of the third aspect.

[0047] The technical solutions provided by the present application will be described in detail below with reference to the embodiments.

[0048] Embodiment 1 Embodiment 1 of the present application provides a crystalline sealing glass powder, and its composition includes: SiO2, B2O3, Al2O3, ZnO, La2O3, MgO, CaO, BaO, and their mass ratio is 13.5:10:5.5:7:30:16:3.5:12.

[0049] Embodiment 2 Embodiment 2 of the present application provides a crystalline sealing glass powder. In terms of mass percentage, its composition includes: SiO2, B2O3, Al2O3, ZnO, CeO2, MgO, CaO, BaO, and their mass ratio is 11:12:5.5:7:35:12:1.5:10.

[0050] Embodiment 3 Embodiment 3 of the present application provides a crystalline sealing glass powder, and its composition includes: SiO2, B2O3, Al2O3, ZnO, Nd2O3, MgO, BaO, and their mass ratio is 8.5:14:5.5:7:40:10:16.

[0051] Embodiment 4 Embodiment 4 of the present application provides a crystalline sealing glass powder, and its composition includes: SiO2, B2O3, Al2O3, ZnO, La2O3, BaO, and their mass ratio is 5:15:1:10:30:30.

[0052] Embodiment 5 Embodiment 5 of the present application provides a crystalline sealing glass powder, and its composition includes: SiO2, B2O3, Al2O3, ZnO, La2O3, CaO, and their mass ratio is 15:10:8:5:45:10.

[0053] Embodiment 6 Example 6 of the present application provides a crystalline sealing glass powder, and its composition includes: SiO2, B2O3, Al2O3, ZnO, CeO2, SrO, and their mass ratio is 10:13:4:8:40:20.

[0054] Example 7 Example 7 of the present application provides a preparation method of a crystalline sealing glass powder, including the following steps: According to the composition of the crystalline sealing glass powder, mix its raw materials with a three-dimensional mixer for 30 min to obtain a mixed material; Put the mixed material into a platinum crucible, cover the crucible, place it in the air atmosphere of a box-type resistance furnace, heat it to 1490 °C at a rate of 5 °C / min, and keep it for 1 h to obtain a glass melt; Pour the glass melt into cold water at 25 °C for water quenching to obtain glass; Mill the glass and pass it through a 200-mesh sieve, and dry it at 85 °C for 240 min to obtain the crystalline sealing glass powder.

[0055] Comparative Example 1 Comparative Example 1 of the present application provides a sealing glass powder, which is a borosilicate glass powder, and its specific composition includes: SiO2, B2O3, Al2O3, TiO2, BaO, CaO, and their mass ratio is 21:10:5:4:55:5.

[0056] The crystalline sealing glass powder of Examples 1 to 6 was prepared according to the preparation method of the crystalline sealing glass powder of Example 7, and its performance was measured with the sealing glass powder of Comparative Example 1, and the expansion coefficient, sealing temperature, softening temperature and fluidity were tested. The results are shown in Table 1. The expansion coefficient of Example 1 is as Figure 2 shown, the XRD pattern of Example 1 is as Figure 3 shown, and the physical diagram of the glass-ceramics formed after encapsulating the glass-ceramics powder of Example 1 is as Figure 4 shown ( Figure 4 the white part in the upper right corner).

[0057] Among them, the test method for the expansion coefficient is: cast the glass into a block, cut it into a spline of 6 mm * 6 mm * 25 mm, and test it with an expansion coefficient instrument.

[0058] The test method for the sealing temperature is: test the medium-temperature viscosity of the glass by the parallel plate method, and determine the sealing temperature through the temperature corresponding to the glass viscosity.

[0059] The test method for the softening temperature is: determine the softening temperature through the expansion coefficient curve obtained by testing with an expansion coefficient instrument.

[0060] The test method for fluidity is as follows: Measure the diameter of the flow column. Press glass powder into a cylinder with a diameter of 12.5 mm and a height of 8 mm, and sinter it into a button shape at 850 °C for 60 min, then measure its diameter.

[0061] Table 1 Performance of the sealing glass powder of Examples 1 to 6 and Comparative Example 1

[0062] As can be seen from Table 1 and Figure 1 it can be seen that the softening temperature and sealing temperature of Examples 1 to 6 are significantly lower than those of the borosilicate glass of Comparative Example 1. At the same time, when sintered under the conditions of the same temperature and time, the flow diameter of Examples 1 to 6 is also significantly larger than that of Comparative Example 1, having better sealing fluidity. The sealing glass powder of the present application can achieve good melting at 1490 °C. The melting temperature of common silicate glasses is usually above 1550 °C, which will cause disadvantages such as high energy consumption and long time in practical applications. Compared with the glass formula of the above Comparative Example 1, the softening temperature of the flat-type solid oxide fuel cell sealing glass powder of Examples 1 to 6 is 650 - 700 °C, the sealing temperature of the sealing glass powder is 830 - 860 °C, and the expansion coefficient after crystallization is 8.7 - 9.5×10 -6 / K, with a high matching degree with metal-metal sealing, achieving the sealing of the solid oxide fuel cell under the conditions of lower cost and shorter time.

[0063] In summary, it can be known that adding light rare earth oxides can effectively inhibit the volatilization of boron in the glass, reduce the generation of pores in the sealing glass, and improve the airtightness of the sealing glass. At the same time, adding alkaline earth metal oxides and light rare earth oxides can effectively adjust the expansion coefficient and characteristic temperature, making the sealing fluidity better and the expansion coefficient higher, so that the glass has an expansion coefficient and working temperature that match the sealing requirements of solid fuel cells. The crystalline sealing glass powder of the present application crystallizes during the sealing process and matches the thermal expansion coefficients of other components of the SOFC.

[0064] In the description of this specification, the description with reference to terms such as "one embodiment / way", "some embodiments / ways", "example", "specific example" or "some examples", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment / way or example are included in at least one embodiment / way or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment / way or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments / ways or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments / ways or examples described in this specification and the features of different embodiments / ways or examples.

[0065] It should be noted that in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element. In this application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0066] The above are only specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application will not be limited to these embodiments shown herein, but rather will conform to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A crystalline sealing glass powder, characterized in that, Applied to a metal-supported solid oxide fuel cell, the composition includes: SiO2, B2O3, Al2O3, ZnO, light rare earth oxides and alkaline earth metal oxides, where: The mass ratio of SiO2, B2O3, Al2O3, ZnO, light rare earth oxides and alkaline earth metal oxides is (5~15):(10~15):(1~8):(5~10):(30~45):(10~30).

2. The crystalline sealing glass powder according to claim 1, wherein, The light rare earth oxides include at least one of La2O3, CeO2 and Nd2O3.

3. The crystalline sealing glass powder according to claim 1, characterized in that, The alkaline earth metal oxides include at least one of MgO, CaO, SrO and BaO.

4. A method for preparing the crystalline sealing glass powder according to any one of claims 1 to 3, characterized in that, It includes the following steps: Mix the raw materials of the crystalline sealing glass powder to obtain a mixed material; Melt the mixed material to obtain a glass melt; Quench the glass melt to obtain glass; Crush the glass to obtain the crystalline sealing glass powder.

5. The preparation method of the crystalline sealing glass powder according to claim 4, characterized in that, In the step of melting the mixed material to obtain a glass melt: The melting temperature is 1400°C to 1600°C; and / or, The heating rate during melting is 3°C / min to 8°C / min; and / or, The holding time during melting is 0.5 to 2 h.

6. The preparation method of the crystalline sealing glass powder according to claim 4, characterized in that, In the step of quenching the glass melt to obtain glass: The quenching method includes any one of water quenching or oil quenching; and / or, The quenching temperature is 0°C to 30°C.

7. The preparation method of the crystalline sealing glass powder according to claim 4, characterized in that, In the step of crushing the glass to obtain the crystalline sealing glass powder: The crushing method includes any one of ball milling or jet milling; and / or, The mesh number of the sieve through which the glass is crushed is 100 to 350 mesh.

8. A sealing glass, characterized in that, Formed by the crystalline sealing glass powder according to any one of claims 1 to 3, where: The softening temperature of the sealing glass is 650 to 700°C; and / or, The sealing temperature of the sealing glass is 830 to 860°C; and / or, The expansion coefficient of the sealing glass is 8.7~9.5×10 -6 / K.

9. A metal-supported solid oxide fuel cell, characterized in that, It includes the sealing glass according to claim 8.

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