CN108520967A - A porous metal-supported microtubular solid oxide fuel cell and its preparation method - Google Patents

Abstract

A porous metal-supported microtubular solid oxide fuel cell and a preparation method thereof belong to the field of new energy materials and electrochemical technology. The method specifically includes: preparation of slurry; preparation of a stainless steel micropipe support layer; sequentially preparing an anode function layer, an electrolyte layer and a cathode support layer on the stainless steel micropipe support layer. The advantages of the present invention are: the present invention uses stainless steel metal as the support body of the microtubular solid oxide fuel cell, the anode functional layer and the electrolyte layer are prepared by a dip-coating process, the cathode functional layer is prepared by a screen printing process, combined with a co-sintering process Sintered forming, this structure has simple preparation process, reliable performance and low cost. The invention has the advantages of simple process, no need of expensive equipment, and the use of cheap stainless steel as the battery support, which greatly reduces the system cost and is suitable for large-scale production.

Description

A porous metal-supported microtubular solid oxide fuel cell and its preparation method

technical field

The invention belongs to the field of new energy materials and electrochemical technology, and in particular relates to a porous metal-supported microtubular solid oxide fuel cell and a preparation method thereof.

Background technique

A solid oxide fuel cell is an all-solid-state energy conversion device that directly converts fuel chemical energy into electrical energy through electrochemical reactions. The main components of a single battery include a dense electrolyte diaphragm and porous anodes and porous cathodes on both sides. So far, yttria-stabilized zirconia (YSZ) is the most well-studied and practically applied oxygen ion conductor solid electrolyte material. Correspondingly, most anode materials are Ni-YSZ cermets, while cathode materials are mostly La _{1– x} Perovskite structure oxide ceramics such as Sr _x MnO ₃ (LSM). During the operation of the battery, oxygen molecules are adsorbed on the surface of the porous cathode and accept electrons from the external circuit, and then dissociate to generate oxygen ions. The oxygen ions then diffuse to the anode through the dense solid electrolyte diaphragm and combine with hydrogen and natural gas in the porous anode. When the fuel undergoes an electrochemical oxidation reaction to generate H ₂ O and CO ₂ , the released electrons are sent back to the cathode through an external circuit. Compared with traditional heat engine power generation technology, SOFCs have the advantages of high efficiency, low emission, and no noise. The primary power generation efficiency can reach 50%~60%. After being linked with a steam turbine, the energy conversion efficiency can reach more than 80%. Compared with fuel cells, SOFCs do not require the use of noble metal catalysts, and their cost is lower, and their high-temperature working conditions can provide higher-quality thermal energy output; unlike renewable energy sources such as solar energy and wind energy, SOFC technology is not affected by regions, environments, and climates. Restrictions, with strong reliability and adaptability. It is a very competitive green power generation technology, and has great application prospects in large-scale power stations, distributed power stations, household combined heat and power systems, and automotive auxiliary power supplies.

In recent years, the miniaturization of SOFC has become one of the research hotspots, and its model is microtubular SOFC or hollow fiber SOFC. This type of battery has the advantages of both tubular and planar SOFCs, and represents a future development direction of SOFCs, which has attracted much attention. The traditional microtubular SOFC is prepared by extrusion process, and it is not easy to adjust the structure of the anode. The ceramic membrane production technology based on the principle of phase inversion has developed into a new method for preparing SOFC supports, electrodes and electrolytes. The ceramic membrane prepared by this method has an asymmetric structure, its porosity is evenly transitioned, and its specific surface area is large, which meets the structural requirements of an ideal support anode for SOFC, and it is easy to deposit a thin electrolyte membrane on it to reduce the electrolyte and electrode. The ohmic resistance in turn reduces the operating temperature of the battery. The application of phase inversion method combined with spinning technology to produce ceramic hollow fibers has opened up a new way for the development of microtubular SOFC. The application of phase inversion method to prepare microtubular SOFC does not require expensive equipment and the process is simple, which can greatly reduce the manufacturing cost of SOFC, and has far-reaching significance for protecting the living environment and stimulating economic development.

The high cost of traditional SOFC materials and the unreliability of battery sealing have seriously hindered the commercialization of SOFC. Ceramic-based microtubular solid oxide fuel cells such as anode support and electrolyte support have low mechanical strength and poor resistance to rapid thermal start. And other issues. The development of SOFC to medium and low temperature is an important direction to solve these problems. When the operating temperature drops to medium temperature (600~800 ^o C) or low temperature (450~600 ^o C), cheap stainless steel materials can be used for supports and batteries The connection body of the stack improves the mechanical strength of the battery structure, and the sealing of the battery stack is easier to achieve at a lower operating temperature, thereby reducing the complexity of the battery stack, which makes the rapid start-up and thermal cycle of SOFC possible.

The metal-supported battery configuration has its unique design concept and can satisfy the advantages of high output performance and low cost at the same time. The development trend of low temperature drives SOFC to gradually transform from traditional ceramic support structures, namely anode support, cathode support and electrolyte support, to metal support structures. Traditional SOFCs generally use stable ceramic materials or metal-ceramic composite materials as their supports. The disadvantages of this kind of support are: the ceramic material is not easy to process, and its thermal shock resistance and weldability are relatively poor, which is not conducive to the assembly of battery stacks, resulting in high preparation costs of SOFC. With the development of science and technology, the research on SOFC in various countries is also deepening, especially as the preparation technology and process of SOFC become more and more mature, the film-forming technology of electrolyte has been improved, and new low-temperature electrolyte materials have been developed. So that the battery can work in the medium and low temperature range of 600 ~ 800 ^o C. Moreover, the selection range of electrode materials has also been expanded, and metal materials have been more and more important in SOFC applications. Therefore, using metal materials as SOFC supports to prepare metal-supported SOFC (MS-SOFC) has become the current SOFC research. hotspots. In summary, the traditional ceramic support structure still has the problems of high cost, poor mechanical strength, and complicated preparation process. It is urgent to develop a new SOFC battery to solve the above problems.

Contents of the invention

The purpose of the present invention is to solve the problems of high cost, poor mechanical strength and complicated preparation process in the current traditional ceramic support structure, and provide a porous metal-supported microtubular solid oxide fuel cell and its preparation method. The obtained battery contains the stainless steel microtube support layer, the mechanical properties of the prepared battery are improved, the interface properties with the anode are improved, and the substantial area for hydrogen oxidation reaction at the anode is increased, and the stainless steel microtube support has excellent Symmetrical structure, and thus improves the performance of the fuel cell, the fuel cell has excellent anti-vibration and rapid hot start performance.

In order to achieve the above object, the technical scheme that the present invention takes is as follows:

A porous metal-supported microtubular solid oxide fuel cell, the solid oxide fuel cell is sequentially composed of a cylindrical stainless steel microtube support layer, an anode functional layer, an electrolyte layer and a cathode functional layer from the inside to the outside ; The diameter of the inner circumference of the stainless steel microtube support layer is 1-2.6mm, the wall thickness is 0.2-0.6mm, and the stainless steel microtube support layer is divided into 3 layers.

A method for preparing the above-mentioned porous metal-supported microtubular solid oxide fuel cell, the method comprising the following steps:

Step 1: Preparation of slurry

(1) Metal polymer slurry: in terms of weight percentage, the content of each component is: stainless steel metal powder 61.8%, polyphenylene ether sulfone 6.2%, N-methylpyrrolidone 27.6%, alcohol 3.1%, polyvinylpyrrolidone 1.3% , the preparation method is as follows: weigh the raw materials and place them in a ball mill tank, and use a planetary ball mill to continuously mill for 48 hours, and the milling speed is 720 r/min;

(2) The composition of the anode dip coating slurry is based on weight percentage: 13.5% NiO, 1.5% SSZ or YSZ, 72% ethanol, 11% terpineol, 2% ethyl cellulose; the electrolyte dip coating slurry composition is based on weight percentage Total: 15% SSZ or YSZ electrolyte powder, 72% ethanol, 11% terpineol, 2% ethyl cellulose; the preparation methods of anode dip coating slurry and electrolyte dip coating slurry are: weigh each component, Put it into a ball mill jar, and undergo ball milling for 48 hours at a speed of 720 r/min or ultrasonic for 5 hours with a power of 500W;

Step 2: Preparation of stainless steel microtube support layer

The stainless steel microtube support layer was prepared by the phase inversion method, specifically: the metal polymer slurry was passed through a 200-mesh sieve to remove impurities, vacuum degassed at room temperature for 20 minutes, then transferred to the raw material tank, and after standing in the raw material tank for 20 min Introduce N ₂ , the inner and outer diameters of the annular spinneret of the phase inversion device are 1.0 mm and 2.6 mm, respectively, and the inner and outer coagulation baths are deionized water and tap water respectively; according to the actual process requirements, adjust the device parameters, and the N ₂ pressure is 0.02 ~0.05 MPa, the flow rate of the internal coagulation bath is 15-20 mL/min, the air gap length is 9-11 cm, spinning into a film, solidified for 24 h, and the stainless steel microtube blank with gradient pore structure is obtained, the stainless steel microtube The green body was naturally dried at room temperature for 24 h, and then sintered by a hanging firing process under a protective atmosphere to obtain a stainless steel microtube support layer;

Step 3: Preparation of anode functional layer and electrolyte layer: prepared by dip coating method, respectively transfer the electrolyte dip coating slurry and anode dip coating slurry in step 1 to a small beaker, clean the outer surface of the stainless steel microtube, and use Seal one end of the stainless steel microtube support layer with paraffin, immerse it in the anode dip coating slurry at a speed of 0.5cm/s, immerse it in the anode dip coating slurry and let it stand for 10~15s, and put the stainless steel microtube at the same speed The support layer was lifted from the anode dip coating slurry to uniformly deposit a layer of anodic film on the surface, hung on an iron frame to dry at room temperature, and dip-coated repeatedly 5 times to obtain a 50 μm thick anode functional layer film. After completion, pre-burn at 1200 ^o C for 2 hours;

After the outer surface of the stainless steel microtube with the anode functional layer was cleaned, it was immersed in the electrolyte dipping slurry at a speed of 0.5 cm/s for 10–15 s, and the stainless steel microtube with the anode functional layer was removed from the electrolyte at the same speed. It is proposed in the dip coating slurry to uniformly deposit a layer of electrolyte film on the surface, and let it stand in the air to dry in the shade. Repeat dip coating 5 times to obtain a 15 μm thick electrolyte film. (5%vol hydrogen and 95%vol argon) were sintered at 1400 ^o C for 2 hours to obtain a metal-supported microtubular solid oxide fuel cell with an anode functional layer and an electrolyte layer;

Step 4: Prepare the cathode functional layer and cathode current collector: use a fine brush to evenly brush a layer of SFM cathode layer on the surface of the electrolyte layer (0.1g of SFM powder is mixed with 0.1 mL of terpineol, add 0.12 g of starch, 0.1 g of B Base cellulose, ground for 15 minutes and mixed evenly), and then sintered at 1080 ^o C for 1 h under hydrogen-argon gas mixture (5% vol hydrogen and 95% vol argon) to prepare the cathode functional layer; coat the silver paste on the cathode On the surface of the functional layer, the silver wire is wound on the coated silver paste, dried at 80 ^o C for 30 minutes, and then sintered at 750 ^o C for 30 minutes to obtain a porous metal-supported microtubular solid oxide fuel cell.

The beneficial effect of the present invention relative to prior art is:

(1) In the present invention, stainless steel metal is used as the support body of the microtubular solid oxide fuel cell, the anode functional layer and the electrolyte layer are prepared by the dip coating process, the cathode functional layer is prepared by the screen printing process, combined with the co-sintering process to sinter and form, The preparation process of this structure is simple, the performance is reliable, and the cost is low.

(2) The present invention relates to a new fuel cell structure and a method for manufacturing metal microtubes. The porous stainless steel microtube support layer is prepared by phase inversion method, and the material is 400 series stainless steel, 300 series stainless steel, nickel-iron alloy, NiCrAlY alloy, Hastelloy-X alloy, Crofer 22APU, and ITM ferritic stainless steel alloy, which improve the mechanical strength and packaging performance of the fuel electrode support, thereby improving the performance and practicality of the fuel cell.

(3) The advantages of the present invention are that the process is simple, does not require expensive equipment, uses cheap stainless steel as the battery support, greatly reduces the system cost, and is suitable for large-scale production.

Description of drawings

Fig. 1 is a schematic diagram of the cross-sectional structure of a porous metal-supported microtubular solid oxide fuel cell, wherein, 1-stainless steel microtube support layer, 2-anode functional layer, 3-electrolyte layer, 4-cathode functional layer;

Fig. 2 is a scanning electron microscope image of a 430L stainless steel metal support layer with an asymmetric structure;

Fig. 3 is a schematic diagram of the overall structure of a phase inversion device;

Fig. 4 is the front view of the spinneret with concentric ring holes in Fig. 3;

Fig. 5 is a top view of the spinneret with concentric ring holes in Fig. 3;

Fig. 6 is a schematic diagram of material distribution in the spinneret with concentric ring holes in Fig. 3;

Fig. 7 is a scanning electron microscope image of a tube wall section of a 430L/NiO-YSZ/YSZ/LSCF microtubular solid oxide fuel cell.

Detailed ways

The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and embodiments, but it is not limited thereto. Any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit of the technical solution of the present invention should be included in the scope of the present invention. Within the protection scope of the present invention.

Compared with the traditional ceramic support structure, the metal-supported SOFC of the present invention has the following advantages: a. Low cost. The price of metal materials is much lower than the ceramic materials used in anodes, cathodes, and electrolytes. b.Quick start. The good thermal conductivity of metal can ensure the fast start-up performance of metal-supported SOFC, so that it can be applied in the mobile field. c. Machinability. Metal stainless steel has good ductility, which will greatly reduce the difficulty of SOFC processing. d. Easy to seal. Using the mature sealing technology of metal materials can avoid the problem of difficult sealing of traditional SOFC. It is precisely because metal materials have the advantages that other materials above do not have. Metal-supported SOFC is regarded as the third generation SOFC, which is expected to replace traditional electrode or electrolyte-supported SOFC and solve the problem of poor mechanical strength of traditional ceramic-based solid oxide fuel cells. question.

Specific Embodiment 1: This embodiment describes a porous metal-supported microtubular solid oxide fuel cell. The solid oxide fuel cell is sequentially composed of a cylindrical stainless steel microtubular support layer 1 , an anode functional layer 2, an electrolyte layer 3 and a cathode functional layer 4; the diameter of the inner circumference of the stainless steel microtube support layer 1 is 1~2.6mm, and the wall thickness is 0.2~0.6mm, and the stainless steel microtube support layer 1 has a total Divided into 3 layers, the battery structure is shown in Figure 1.

Specific embodiment two: a method for preparing the porous metal-supported microtubular solid oxide fuel cell described in specific embodiment one, the method includes the following steps:

Step 1: Preparation of slurry

(1) Metal polymer slurry: in terms of weight percentage, the content of each component is: stainless steel metal powder 61.8%, polyphenylene ether sulfone (PESf) 6.2% is a high molecular polymer, as a binder, N- Methylpyrrolidone (NMP) 27.6%, alcohol 3.1%, polyvinylpyrrolidone (PVP) 1.3%, the preparation method is as follows: weigh the raw materials and place them in a ball mill jar, and use a planetary ball mill for continuous ball milling for 48 h at a milling speed of 720 r /min to ensure that the stainless steel metal powder is uniformly dispersed in the organic solvent to obtain a uniform and stable metal-polymer slurry. The metal-polymer slurry used in the experiment should have good stability and fluidity, and have a certain viscosity. (13~14mPa.s).

(2) The composition of the anode dip coating slurry is based on weight percentage: 13.5% NiO, 1.5% SSZ or YSZ, 72% ethanol, 11% terpineol, 2% ethyl cellulose; the electrolyte dip coating slurry composition is based on weight percentage Total: 15% SSZ or YSZ electrolyte powder, 72% ethanol, 11% terpineol, 2% ethyl cellulose; the preparation methods of anode dip coating slurry and electrolyte dip coating slurry are: weigh each component, Put it into a ball mill jar and mill for 48 hours at a speed of 720 r/min or ultrasonically for 5 hours with a power of 500W;

Step 2: Preparation of stainless steel microtube support layer

The stainless steel microtube support layer was prepared by the phase inversion method, specifically: pass the metal-polymer slurry through a 200-mesh sieve to remove impurities, use the device shown in Figure 3, vacuum degas at room temperature for 20 min, and then transfer to the stainless steel spinning stock solution Tank, that is, the raw material tank, put N ₂ into the raw material tank after standing still for 20 minutes. The inner and outer diameters of the self-made phase inversion device annular spinneret are 1.0mm and 2.6mm respectively. The drawings of the device are shown in Figure 4 and Figure 5 , the inner and outer coagulation baths were deionized water and tap water respectively; according to the actual process requirements, the parameters of the device were adjusted, the _N2 pressure was 0.02-0.05 MPa, the flow rate of the inner coagulation bath was 15-20 mL/min, the air gap length (spray The distance from the thread opening to the surface of the coagulation bath) was 9-11 cm, spun to form a film, and solidified for 24 hours to obtain a stainless steel microtube blank with a gradient pore structure. The stainless steel microtube blank was naturally dried at room temperature for 24 hours. h, and then sintered and formed by a hanging firing process under a protective atmosphere to obtain a stainless steel microtube support layer. The prepared stainless steel microtube support layer has an asymmetric structure, the finger-shaped channels are distributed on both sides of the tube wall, and the middle of the tube wall is a sponge channel structure, and the finger-shaped channels are connected through the sponge channels. Figure 2 is a stainless steel with an asymmetric structure. Scanning electron micrograph of the metal support layer;

Step 3: Preparation of anode functional layer and electrolyte layer: prepared by dip coating method, respectively transfer the electrolyte dip coating slurry and anode dip coating slurry in step 1 to a small beaker, clean the outer surface of the stainless steel microtube, and use Seal one end of the stainless steel microtube support layer with paraffin, immerse it in the anode dip coating slurry at a speed of 0.5cm/s, immerse it in the anode dip coating slurry and let it stand for 10~15s, and put the stainless steel microtube at the same speed The supporting layer is taken out from the anode dip coating slurry, and a layer of anodic film is evenly deposited on the surface, hung on an iron frame to dry at room temperature, and dip-coated repeatedly for 5 times to obtain a certain thickness of anodic film. ^o C pre-fired for 2 hours to obtain a certain bonding force between the anode functional layer and the stainless steel microscopic support layer, which is convenient for the subsequent electrolyte membrane coating operation; then dip-coat the electrolyte dip-coating slurry in the same way, and dry at room temperature Afterwards, it was sintered at 1400 ^o C for 2 h under hydrogen-argon gas mixture to obtain a metal-supported microtubular solid oxide fuel cell with an anode functional layer and an electrolyte layer; the electrolyte membrane of the prepared half-cell was smooth and transparent, due to the It is densified by high-temperature sintering and can be tightly combined with the anode.

Step 4: Prepare the cathode functional layer and the cathode current collector: use a fine brush to evenly brush a layer of SFM cathode layer slurry on the surface of the electrolyte layer, and then sinter at 1080 ^o C for 1 h under hydrogen-argon mixed gas to prepare the cathode functional layer ; Coat the silver paste on the surface of the cathode functional layer, then wind the silver wire on the coated silver paste, dry at 80 ^o C for 30 minutes, and then sinter at 750 ^o C for 30 minutes to obtain a porous metal-supported microtubular solid oxide fuel cell. The presence of the current collector is convenient for current collection and battery performance testing.

In this embodiment, the anode functional layer is a NiO-SSZ composite electrode, the electrolyte layer is SSZ, and the cathode functional layer is Sr ₂ Fe _1.5 Mo _0.5 O ₆ .

Specific embodiment three: the preparation method of the porous metal-supported microtubular solid oxide fuel cell described in specific embodiment two, in step one, the material of the stainless steel metal powder is 400 series stainless steel, 300 series stainless steel, nickel Iron alloys, NiCrAlY alloys, Hastelloy-X alloys, Crofer 22APU and ITM ferritic stainless steel alloys.

Embodiment 4: The preparation method of the porous metal-supported microtubular solid oxide fuel cell described in Embodiment 2, in step 2, the flow rate of the internal coagulation bath is 17.5mL/min, and the nitrogen pressure is 0.05MPa , the air gap length is 10cm; the external coagulation bath is tap water.

Embodiment 5: The preparation method of the porous metal-supported microtubular solid oxide fuel cell described in Embodiment 2, in step 2, the protective atmosphere is argon, and the sintering process is specifically: at 2 ^o C The temperature was raised to 1300 ^o C at a heating rate of 1/min, kept for 2 h, and then dropped to room temperature naturally.

All anode functional layers, electrolyte layers, and cathode functional layers can be prepared by other coating processes (including electrochemical vapor deposition, chemical vapor deposition, electrophoretic deposition, sputtering, and plasma spraying).

The invention prepares the stainless steel micropipe support body by using the phase inversion method to provide physical support and current collector for the whole battery. The battery of the present invention mainly uses a stainless steel support tube as the anode current collector. Similarly, silver paste and silver wire can also be used as current-collecting materials for the cathode and anode of the battery. On the silver paste, after drying, it was sintered at 750 ^o C for 30 minutes to form a strong bond between the silver paste and the cathode, anode and silver wire. Finally, the microtubular SOFC single cell was sealed on the corundum with ceramic sealant. in ceramic test tubes.

Example 1:

Preparation of 430L/NiO-YSZ/YSZ/LSCF microtubular solid oxide fuel cells.

According to the following steps: preparation of metal polymer slurry, electrolyte dip coating slurry, anode dip coating slurry; preparation of stainless steel metal asymmetric microtubes with hierarchical porous structure; NiO-based anode catalyst deposition, YSZ electrolyte layer deposition and sintering; LSCF cathode layer deposition and sintering.

(1) Preparation of metal-polymer slurry, electrolyte dip coating slurry, and anode dip coating slurry

In the metal-polymer slurry, the organic polymer is polyethersulfone (PESf), the solvent is N-methylpyrrolidone (NMP), the additive is polyvinylpyrrolidone (PVP), and 430L stainless steel metal powder ( 500 mesh) as the raw material of the support body; the weight percentage of each component is: PESf 6.2%, NMP 27.6%, PVP 1.3%, 430L stainless steel metal powder 61.8%, alcohol 3.1%; the composition of the anode dip coating slurry is 13.5%NiO, 1.5% YSZ, 72% ethanol, 11% terpineol, 2% ethyl cellulose, of which NiO is used as the anode functional layer; the composition of the electrolyte dip coating slurry is 15% YSZ, 72% ethanol, 11% terpineol, 2% ethyl cellulose with YSZ as electrolyte.

According to the above weight percentage, first weigh the solvent NMP and place it in a ball mill tank, add the additive PVP to dissolve it, then add 430L stainless steel metal powder, after ball milling for 24 hours, add the organic polymer PESf, and continue to stir for 24 hours to make it completely Dissolved to obtain a metal polymer slurry. The method of anode dip coating slurry and electrolyte dip coating slurry is the same: Weigh the raw materials according to the weight percentage, place them in a beaker, and ultrasonicate for 5 h.

(2) Preparation of stainless steel metal asymmetric microtubes with hierarchical porous structure

The metal polymer slurry prepared above was vacuum-degassed for 20 min using the device shown in Figure 3, and then moved to the raw material tank, with deionized water as the core liquid and tap water as the outer coagulation bath, passing through the concentric ring holes The spinneret spun the metal-polymer slurry into the external coagulation bath. The structure of the spinneret with concentric ring holes is shown in Fig. 6. It was soaked in the external coagulation bath for 24 h, and then it was taken out to dry and solidify to obtain a gradient pore structure. 430L stainless steel double-layer hollow microtube precursor. The cured 430L stainless steel double-layer hollow fiber precursor was straightened, dried, and sintered at 1200 ^o C for 2 h under hydrogen-argon gas mixture to obtain porous stainless steel asymmetric microtubes. Figure 2 shows the asymmetric structure Scanning electron micrograph of the stainless steel metal support layer.

(3) Preparation of anode and electrolyte functional layers

Transfer the electrolyte dip coating slurry and anode dip coating slurry in (1) to a small beaker, seal one end of the porous stainless steel asymmetric microtube with paraffin, and dip into the anode dip coating slurry at a speed of 0.5cm/s After standing still for 10~15s, take out the slurry at the same speed, hang it on the iron frame to dry at room temperature, and repeat the dip coating 5 times. Then the electrolyte was dip-coated in the same way, dried at room temperature, and then sintered at 1400 ^o C for 2 h under a hydrogen-argon mixture to obtain a metal-supported microtubular solid oxide fuel cell with an anode functional layer and an electrolyte layer.

(4) Preparation of LSCF cathode functional layer

Use terpineol as a solvent to prepare a slurry of 60% LSCF and 40% GDC, then add 10% starch and 12% ethyl cellulose to it, ultrasonicate for 5 h, and use a fine-bristled brush to clean the electrolyte in stainless steel microtubes. A layer of LSCF cathode layer was uniformly brushed on the surface, and sintered at 1080 ^o C for 1 h under hydrogen-argon gas mixture.

Figure 7 shows the structure of a 430L/NiO-YSZ/YSZ/LSCF asymmetric microtube solid oxide fuel cell. The thickness of the 430L stainless steel microtube support layer in the inner layer is 0.4mm, and the NiO-YSZ anode function in the outer layer The thickness of the layer is 10um, the thickness of the YSZ electrolyte layer is 10um, and the thickness of the LSCF cathode functional layer is 50um. The cross-sectional structure of the battery tube wall is shown in Figure 7.

Example 2:

Preparation of ITM/NiO-YSZ/YSZ/LSCF microtubular solid oxide fuel cells.

According to the following steps: preparation of metal polymer slurry, electrolyte dip coating slurry, anode dip coating slurry; preparation of stainless steel metal asymmetric microtubes with hierarchical porous structure; NiO-based anode catalyst deposition; YSZ electrolyte layer deposition and sintering; LSCF cathode layer deposition and sintering.

(1) Preparation of metal-polymer slurry, electrolyte dip coating slurry, and anode dip coating slurry

In the metal polymer slurry, the organic polymer is polyether vanadium (PESf), the solvent is N-methylpyrrolidone (NMP), the additive is polyvinylpyrrolidone (PVP); ITM stainless steel metal powder ( 500 mesh) as the raw material of the support body; the weight percentage of each component is: PESf 6.2%, NMP 27.6%, PVP 1.3%, ITM stainless steel metal powder 61.8%, alcohol 3.1%; the composition of the anode dip coating slurry is 13.5%NiO, 1.5% YSZ, 72% ethanol, 11% terpineol, 2% ethyl cellulose, of which NiO is used as the anode functional layer; the composition of the electrolyte dip coating slurry is 15% YSZ, 72% ethanol, 11% terpineol, 2% ethyl cellulose with YSZ as electrolyte.

According to the above weight percentage, first weigh the solvent NMP and place it in a ball milling tank, add the additive PVP to dissolve it, then add ITM stainless steel metal powder, after ball milling for 24 h, add the organic polymer PESf, and continue stirring for 24 h to make it completely Dissolved to obtain a metal polymer slurry. The method of anode dip coating slurry and electrolyte dip coating slurry is the same: Weigh the raw materials according to the weight percentage, place them in a beaker, and ultrasonicate for 5 h.

(2) Preparation of stainless steel metal asymmetric microtubes with hierarchical porous structure

The metal polymer slurry prepared above was vacuum-degassed for 20 min using the device shown in Figure 3, and then moved to the raw material tank, with deionized water as the core liquid and tap water as the outer coagulation bath, passing through the concentric ring holes The spinneret spun the metal-polymer slurry into the external coagulation bath, soaked in the external coagulation bath for 24 h, and then took it out to dry and solidify to obtain the ITM stainless steel double-layer hollow fiber precursor with gradient pore structure. The cured ITM stainless steel double-layer hollow fiber precursor was straightened, dried, and sintered at a high temperature of 1200 ^o C for 2 h under hydrogen-argon gas mixture to obtain porous stainless steel asymmetric microtubes. The spinneret structure of concentric ring holes was as follows: Figure 6 shows.

(3) Preparation of anode and electrolyte functional layers

Transfer the electrolyte dip coating slurry and anode dip coating slurry in (1) to a small beaker, seal one end of the porous stainless steel asymmetric microtube with paraffin, and dip into the anode dip coating slurry at a speed of 0.5cm/s After standing still for 10~15s, take out the slurry at the same speed, hang it on the iron frame to dry at room temperature, and repeat the dip coating 5 times. Then the electrolyte was dip-coated in the same way, dried at room temperature, and then sintered at 1400 ^o C for 2 h under a hydrogen-argon mixture to obtain a metal-supported microtubular solid oxide fuel cell with an anode functional layer and an electrolyte layer.

(4) Preparation of LSCF cathode functional layer

Use terpineol as a solvent, configure a slurry of 60% LSCF and 40% GDC, add 10% starch and 12% ethyl cellulose to it, ultrasonicate for 5 hours, and use a fine-bristled brush on the stainless steel microtube electrolyte A layer of LSCF cathode layer was uniformly brushed on the surface, and sintered at 1080 ^o C for 1 hour under hydrogen-argon gas mixture.

Example 3:

Preparation of Ni-Fe/NiO-SSZ/SSZ/SFM microtubular solid oxide fuel cells.

According to the following steps: preparation of metal polymer slurry, electrolyte dip coating slurry, anode dip coating slurry; preparation of stainless steel metal asymmetric microtubes with hierarchical porous structure; NiO-based anode catalyst deposition; SSZ electrolyte layer deposition and sintering; SFM cathode layer deposition and sintering.

(1) Preparation of metal-polymer slurry, electrolyte dip coating slurry, and anode dip coating slurry

In the metal-polymer slurry, the organic polymer is polyethersulfone (PESf), the solvent is N-methylpyrrolidone (NMP), the additive is polyvinylpyrrolidone (PVP); Ni-Fe stainless steel metal is used powder (500 mesh) as the support material;

The weight percentage of each component is: PESf 6.2%, NMP 27.6%, PVP 1.3%, Ni-Fe stainless steel metal powder 61.8%, alcohol 3.1%; the composition of the anode dip coating slurry is 13.5%NiO, 1.5%SSZ, 72% Ethanol, 11% terpineol, 2% ethyl cellulose, of which NiO is used as the anode functional layer; electrolyte dip coating slurry composition is 15% SSZ, 72% ethanol, 11% terpineol, 2% ethyl cellulose , where YSZ acts as the electrolyte.

According to the above weight percentage, first weigh the solvent NMP and place it in a ball mill tank, add the additive PVP to dissolve it, then add Ni-Fe stainless steel metal powder, after ball milling for 24 h, add the organic polymer PESf, and continue stirring for 24 h to make It dissolves completely, yielding a metal-polymer slurry. The method of anode dip coating slurry and electrolyte dip coating slurry is the same: Weigh the raw materials according to the weight percentage, place them in a beaker, and ultrasonicate for 5 h.

(2) Preparation of stainless steel metal asymmetric microtubes with hierarchical porous structure

The metal polymer slurry prepared above was vacuum-degassed for 20 min using the device shown in Figure 3, and then moved to the raw material tank, with deionized water as the core liquid and tap water as the outer coagulation bath, passing through the concentric ring holes The spinneret spun the metal-polymer slurry into the external coagulation bath, soaked in the external coagulation bath for 24 h, and then took it out to dry and solidify to obtain a Ni-Fe stainless steel double-layer hollow microtube precursor with a gradient pore structure. The cured Ni-Fe stainless steel double-layer hollow fiber precursor was straightened, dried, and sintered at a high temperature of 1200 ^o C for 2 h under a hydrogen-argon mixture to obtain a porous stainless steel asymmetric microtube with concentric ring holes. The header structure is shown in Figure 3.

(3) Preparation of anode and electrolyte functional layers

Transfer the electrolyte dip coating slurry and anode dip coating slurry in (1) to a small beaker, seal one end of the porous stainless steel asymmetric microtube with paraffin, and dip into the anode dip coating slurry at a speed of 0.5cm/s After standing still for 10~15s, take out the slurry at the same speed, hang it on the iron frame to dry at room temperature, and repeat the dip coating 5 times. Then the electrolyte was dip-coated in the same way, dried at room temperature, and then sintered at 1400 ^o C for 2 h under a hydrogen-argon mixture to obtain a metal-supported microtubular solid oxide fuel cell with an anode functional layer and an electrolyte layer.

(4) Preparation of LSCF cathode functional layer

Use terpineol as a solvent, configure a slurry of 60% LSCF and 40% GDC, add 10% starch and 12% ethyl cellulose to it, ultrasonicate for 5 hours, and use a fine-bristled brush on the surface of the microtube electrolyte Brush a layer of LSCF cathode layer evenly, and sinter at 1080 ^o C for 1 hour under hydrogen-argon mixed gas.

Claims (5)

1. a kind of porous metals support type micro-tubular solid oxide fuel cell, it is characterised in that：The soild oxide Fuel cell is from the inside to the outside successively by cylindric stainless steel micro pipe supporting layer（1）, anode functional layer（2）, electrolyte layer（3）With And cathode functional（4）Composition；The stainless steel micro pipe supporting layer（1）A diameter of 1 ~ the 2.6mm of inner peripheral surface, wall thickness be 0.2 ~ 0.6mm, stainless steel micro pipe supporting layer（1）It is divided into 3 layers.

2. a kind of preparation method of porous metals support type micro-tubular solid oxide fuel cell described in claim 1, It is characterized in that：The method includes the following steps:

Step 1：The preparation of slurry

（1）The preparation of metal-containing polymer slurry：In percentage by weight, each component content is：Stainless steel metal powder 61.8%, Poly-s 179 6.2%, N-Methyl pyrrolidone 27.6%, alcohol 3.1%, polyvinylpyrrolidone 1.3%, preparation method are：It weighs Each raw material is placed in ball grinder, using 48 h of planetary ball mill continuous ball milling, 720 r/min of rotational speed of ball-mill；

（2）The preparation of anode dip-coating slurry and electrolyte dip-coating slurry：Anode dip-coating paste composition is in percentage by weight： 13.5% NiO, 1.5% SSZ or YSZ, 72% ethyl alcohol, 11% terpinol, 2% ethyl cellulose；Electrolyte dip-coating paste composition according to Weight percent meter：15%SSZ or YSZ electrolyte powders, 72% ethyl alcohol, 11% terpinol, 2% ethyl cellulose；Anode dip-coating is starched Material and electrolyte dip-coating slurry preparation method are：Each component is weighed, 48 h of ball milling in ball grinder is put into, rotating speed is 720 r/ Min or 5 h ultrasounds, power are 500W；

Step 2：Prepare stainless steel micro pipe supporting layer

Stainless steel micro pipe supporting layer is prepared using phase inversion, specially：Metal-containing polymer slurry is crossed into 200 mesh and weeds out removal of impurities Matter is transferred in head tank after 20 min of vacuum outgas, N is passed through after 20 min are stood in head tank at room temperature₂, inversion of phases dress It is respectively 1.0mm and 2.6mm to set annular spinning nozzle inner and outer diameter, and inside and outside coagulating bath is respectively deionized water and tap water；According to Actual technological requirement, regulating device parameter, N₂Pressure is 0.02 ~ 0.05 MPa, interior coagulating bath flow velocity be 15 ~ 20 mL/min, Gas length is 9 ~ 11 cm, and spinning film forming cures 24 h, obtains the stainless steel micro pipe biscuit for having gradient pore structured, will not Rust steel micro-pipe biscuit spontaneously dry 24 h at room temperature, then under protective atmosphere using hang firing technique sinter molding to get to Stainless steel micro pipe supporting layer；

Step 3：Prepare anode functional layer and electrolyte layer：It is prepared using dip coating method, respectively by the electrolyte in step 1 Dip-coating slurry and anode dip-coating slurry are transferred in small beaker, with paraffin that stainless steel is micro- after the cleaning of stainless steel micro pipe outer surface Pipe supporting layer one end seals, and is immersed in anode dip-coating slurry with the speed of 0.5cm/s, after standing 10 ~ 15s, at a same speed Stainless steel micro pipe supporting layer is proposed from anode dip-coating slurry, hanging room temperature on brandreth is dried, dip-coating 5 times repeatedly, coating After the completion 1200^oC preheatings 2h；Then dip-coating electrolyte dip-coating slurry in the same way, room temperature dry after in hydrogen argon 1400 under gaseous mixture^oIt is sintered 2 h at a temperature of C, obtains having anode functional layer and the metallic support type micro-tubular of electrolyte layer solid Oxide body fuel cell；

Step 4：Prepare cathode functional and cathode current collector：Using fine, soft fur brush one layer of the moon is uniformly brushed in electrolyte layer surface Pole layer slurry, then hydrogen-argon-mixed lower 1080^oC is sintered 1 h, that is, cathode functional is prepared；By silver paste coated in the moon Pole function layer surface, then filamentary silver is wrapped in coated silver paste, 80^oIn 750 after C drying 30min^oC be sintered 30min to get To porous metals support type micro-tubular solid oxide fuel cell.

3. the preparation method of porous metals support type micro-tubular solid oxide fuel cell according to claim 2, It is characterized in that：In step 1, the material of the stainless steel metal powder is 400 series stainless steels, 300 series stainless steels, ferronickel One kind in alloy, NiCrAlY alloys, Hastelloy-X alloys, Crofer 22APU and ITM ferritic stainless steel alloys.

4. the preparation method of porous metals support type micro-tubular solid oxide fuel cell according to claim 2, It is characterized in that：In step 2, the interior coagulating bath flow is 17.5mL/min, nitrogen pressure 0.05MPa, and gas length is 10cm。

5. the preparation method of porous metals support type micro-tubular solid oxide fuel cell according to claim 2, It is characterized in that：In step 2, the protective atmosphere is argon gas, and sintering process is specially：With 2^oThe heating rate liter of C/min Temperature is to 1300^oC keeps the temperature 2 h, is down to room temperature naturally.