CN111416134A - Metal flat tube support, battery/electrolytic cell and battery stack structure - Google Patents

Metal flat tube support, battery/electrolytic cell and battery stack structure Download PDF

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Publication number
CN111416134A
CN111416134A CN202010246215.7A CN202010246215A CN111416134A CN 111416134 A CN111416134 A CN 111416134A CN 202010246215 A CN202010246215 A CN 202010246215A CN 111416134 A CN111416134 A CN 111416134A
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flat tube
metal flat
battery
fuel gas
anode
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CN111416134B (en
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李成新
康思远
李甲鸿
李长久
张山林
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Xian Jiaotong University
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Xian Jiaotong University
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/002—Shape, form of a fuel cell
    • H01M8/004—Cylindrical, tubular or wound
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B1/00—Electrolytic production of inorganic compounds or non-metals
    • C25B1/01—Products
    • C25B1/02—Hydrogen or oxygen
    • C25B1/04—Hydrogen or oxygen by electrolysis of water
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
    • C25B9/60—Constructional parts of cells
    • C25B9/63—Holders for electrodes; Positioning of the electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/02—Details
    • H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/02—Details
    • H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
    • H01M8/0286—Processes for forming seals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
    • H01M8/04201—Reactant storage and supply, e.g. means for feeding, pipes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
    • H01M8/1231—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte with both reactants being gaseous or vaporised
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
    • H01M8/241—Grouping of fuel cells, e.g. stacking of fuel cells with solid or matrix-supported electrolytes
    • H01M8/2425—High-temperature cells with solid electrolytes
    • H01M8/243—Grouping of unit cells of tubular or cylindrical configuration
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
    • H01M8/2457—Grouping of fuel cells, e.g. stacking of fuel cells with both reactants being gaseous or vaporised
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
    • H01M2008/1293—Fuel cells with solid oxide electrolytes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Electrochemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • General Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Fuel Cell (AREA)

Abstract

The invention provides a metal flat tube support body, a battery/electrolytic cell and a battery stack structure. Wherein, flat tubular metal pipe support structure includes: a closed end, a porous structure, a fuel gas flow passage, an open end; the closed end and the open end are respectively positioned at two ends of the porous structure; the fuel gas flow channel is arranged in the porous structure and used for fuel gas circulation; the closed end is a dense structure for sealing the first end of the fuel gas flow passage. The sealing end and the opening end in the structure provided by the invention are respectively contacted with the electrolyte layer, so that the self-sealing purpose is achieved, and the sealing problem in the metal support type solid oxide fuel cell is effectively solved.

Description

Metal flat tube support, battery/electrolytic cell and battery stack structure
Technical Field
The invention relates to the technical field of energy sources, in particular to a metal flat tube support body, a battery/electrolytic cell and a battery stack structure.
Background
A Solid Oxide Fuel Cell (SOFC) is a Solid-state power generation device, which has high power generation efficiency, operates without noise and pollution, and directly converts chemical energy of fuel into electric energy without combustion. The solid oxide fuel cell functional layer mainly comprises an anode, an electrolyte and a cathode.
The SOFC structures developed at present mainly include two basic structures, namely, a tubular structure and a plate structure. The greatest difference between the two is whether the collecting current conducting direction is perpendicular to the electrolyte membrane direction or parallel to the electrolyte membrane direction. The flat plate type fuel cell has the advantages of small current path, high power density and easy design of series-parallel connection structure. But has the disadvantage that sealing at high temperature is difficult, and the typical working temperature is between 600-800 ℃, and in order to separate the fuel gas at the anode side from the oxidizing gas at the cathode side, a high-temperature-resistant sealing mode or material needs to be selected.
The tubular SOFC has the advantages of no need of high-temperature sealing (sealing can be carried out at a cold end), stable performance, no obvious attenuation in operation for tens of thousands of hours and the like. Due to the excellent sealing performance, the working temperature of the battery can be greatly improved, and higher power output can be obtained. The tubular cell has a disadvantage in that its current path is long and cathode side current collection is difficult.
The flat tube solid oxide fuel cell combines the design of a flat plate and a tube solid oxide fuel cell, not only maintains certain sealing performance of a tube, but also improves a current collection path, and is a design applied to miniaturized equipment. However, the conventional flat tube type solid oxide fuel cell adopts an anode support which is usually nickel-based metal ceramic, so that the cost is high, the brittleness is high, the conductivity is not as high as that of metal, the long-term stable operation of the cell is not facilitated, and the conventional flat tube type cell functional layer only covers one surface of a flat tube, so that the volume power density is not high.
The metal supported solid oxide fuel cell is a new structure, and adopts porous metal as support body, on which the anode, electrolyte and cathode are prepared, and because the support body is made of metal, the electrode and electrolyte component can be made into the form of film, so that the internal resistance and electrode polarization of the cell can be greatly reduced, and the cell performance can be raised. Because of the strength and the heat conductivity of the metal, the metal support type solid oxide fuel cell has the characteristics of low cost, high strength and high thermal shock resistance, and the sealing between the metal support body and the connector can also adopt a mature welding technology.
However, the metal-supported solid oxide fuel cell is mainly flat, and it is necessary to solve the sealing problem, and if the metal-supported solid oxide fuel cell is connected by a mature welding technique, the sealing performance is poor at high temperature.
Disclosure of Invention
The invention provides a metal flat tube support body, a battery/electrolytic cell and a battery stack structure, which are used for solving the sealing problem in a metal support type solid oxide fuel cell.
In a first aspect, the present invention provides a metal flat tube support structure, which has a first end, a second end and a support main body;
the first end is a closed end, the second end is an open end, the first end is opposite to the second end, and the first end and the second end are positioned on two sides of the support main body;
the support main body is of a porous structure, and a fuel gas flow channel is arranged in the support main body and used for fuel gas circulation;
the closed end is of a compact structure and is used for sealing the first end of the fuel gas flow channel;
the opening end is of a compact structure and is used for sealing the second end of the fuel gas flow passage, and a fuel gas inlet and a fuel gas outlet are formed in the compact structure; the fuel gas inlet is used for introducing fuel gas; the fuel gas outlet is used for fuel gas outflow.
Preferably, the metal flat tube support body structure is provided with an upper plane and a lower plane, and the distance between the upper plane and the lower plane is 3-20 mm; the width of the metal flat tube support body structure is more than 2 times of the distance.
Preferably, the length of the support main body accounts for 50% -90% of the length of the metal flat tube support body structure.
Preferably, the porosity of the support body is 15-60%.
Preferably, the preparation method of the metal flat tube support structure at least comprises powder metallurgy.
Preferably, the material for preparing the metal flat tube support structure at least comprises one of iron-chromium alloy, iron-nickel alloy and pure chromium.
In a second aspect, the present invention provides a metal flat tube supported solid oxide fuel cell/electrolyser structure, comprising: the metal flat tube support structure of the first aspect, the anode, the electrolyte and the cathode;
the battery anode or the electrolytic cell cathode covers the support main body of the metal flat tube support body structure, wherein the length of the battery anode or the electrolytic cell cathode is greater than or equal to that of the support main body and is smaller than that of the metal flat tube support body structure;
the electrolyte covers the battery anode or the electrolytic cell cathode, wherein the length of the electrolyte is greater than that of the battery anode or the electrolytic cell cathode and is less than or equal to that of the metal flat tube support structure, and the electrolyte is respectively contacted with the closed end and the open end of the metal flat tube support structure;
the battery cathode or the electrolytic cell anode covers the electrolyte, and the area of the battery cathode or the electrolytic cell anode is larger than or equal to that of the battery anode or the electrolytic cell cathode.
Preferably, the first and second electrodes are formed of a metal,
the battery anode or the electrolytic battery cathode covers the upper plane and the lower plane of the support main body of the metal flat pipe support body structure; or
The battery anode or the electrolytic battery cathode covers the upper surface and the lower surface of the support main body of the metal flat pipe support body structure; or
The battery anode or the electrolytic cell cathode covers the whole outer surface of the support main body of the metal flat tube support body structure.
Preferably, the covering methods of the anode, the electrolyte layer and the cathode all adopt spraying or sintering.
In a third aspect, the present invention provides a solid oxide fuel cell stack structure, comprising: a solid oxide fuel cell stack structure of two or more of the solid oxide fuel cell structures described in the second aspect.
The invention provides a metal flat tube support body, a battery/electrolytic cell and a battery stack structure. Wherein, flat tubular metal resonator supporting body structure includes: closed end, porous structure, fuel gas flow path, open end, and the open end includes: a fuel gas inlet, a fuel gas outlet and a dense structure; the battery/cell structure includes: according to the metal flat tube support body, the anode, the electrolyte and the cathode, in the battery/electrolytic cell structure, the battery anode or the electrolytic cell cathode covers the upper plane and the lower plane of the porous structure of the metal flat tube support body, the electrolyte covers the battery anode or the electrolytic cell cathode, and two ends of the electrolyte are respectively contacted with the closed end and the open end of the metal flat tube support body; a cell stack structure includes two or more cell structures provided herein. Through adopting the battery of the structure that this application provided, need not adopt high temperature extra sealing material, the effectual manufacturing process who simplifies the battery pile is favorable to solid oxide fuel cell's commercial popularization.
Moreover, each structure provided by the invention also has the following advantages:
1. the metal flat tube support body provided by the invention is divided into three parts according to the porosity, namely a middle porous structure and compact structures at two ends (namely a compact structure at an open end and a compact structure at a closed end) are sequentially arranged, the compact structures at the two ends are contacted with a compact electrolyte, gas leakage is prevented, a battery is well sealed, the sealing is not required to be carried out by adopting technologies such as welding, the self-sealing characteristic is realized, and the problem of poor sealing performance in the technologies such as welding is solved.
2. The metal flat tube supporting body provided by the invention has the characteristics of one closed end and one open end, so that the problem of difficult sealing caused by the adoption of the supporting body with two open ends in the related technology is solved. Wherein, one end is sealed, namely, a compact structure integrated with the porous structure is adopted to carry out self-sealing on the porous structure, so as to prevent air leakage and avoid additional sealing connection operation; the one end opening (namely the opening end) means that a fuel gas inlet and a fuel gas outlet are arranged in the opening end, the fuel gas inlet and the fuel gas outlet are arranged in a compact structure, the compact structure has the sealing effect on the fuel gas inlet and outlet and a porous structure, and the compact structure is integrally prepared with the porous structure, the fuel gas inlet and the fuel gas outlet, and is prepared at one time to achieve the purpose of self sealing.
3. According to the invention, the flat metal support and the flat tube design are combined, and the operation of one-time preparation is adopted, so that the metal flat tube support body with the integrated structure characteristic is obtained, the sealing difficulty of the solid oxide fuel cell is obviously improved, the manufacturing cost is reduced, and the volume power density of the cell is greatly improved.
4. The upper plane and the lower plane of the porous structure in the metal flat tube support body provided by the invention can be wrapped by a battery anode or an electrolytic cell cathode, and then an electrolyte and the battery cathode or the electrolytic cell anode are sequentially wrapped on the two planes respectively, so that the battery/electrolytic cell and the battery stack are obtained, and the effective area of the battery/electrolytic cell is increased by utilizing the upper plane and the lower plane, so that the volume power density of the battery is improved.
5. According to the open end of the metal flat tube support body, the compact structure wraps the gas outlet and the gas inlet, so that when a battery is used, the compact structure and the base are simply welded to achieve the purpose of sealing, the temperature of the joint of the base is low, and the problem of sealing failure of the welded joint cannot be caused.
6. Compared with an anode flat tube, the metal flat tube support body provided by the invention has the advantages that the strength is improved, the heat conductivity is improved, the metal flat tube support body can be quickly started, and the cost is reduced.
In addition, the metal flat tube support type solid oxide fuel cell structure with the self-sealing end provided by the invention adopts a newly designed flat tube structure, so that an outlet and an inlet of fuel gas can be sealed at a lower temperature. The battery functional layer surrounds the whole flat tube, and the effective area of the battery is greatly increased, so that the volume power density of the battery is increased. The flat metal supporting tubes are adopted, so that the material cost is reduced, the mechanical property and the conductivity of the battery are improved, the electrode can be thinned, and the polarization impedance of the electrode is reduced. The common advantages of metal support and flat tube batteries are achieved. The battery with the structure does not need to adopt high-temperature extra sealing materials, effectively simplifies the manufacturing process of the battery stack, and is beneficial to the commercial popularization of the solid oxide fuel battery. The electrolytic cell in this application has at least the same advantages as the battery and will not be described in detail herein.
Drawings
Fig. 1 is a schematic cross-sectional view illustrating a support structure of a metal flat tube according to an embodiment of the present invention;
fig. 2 is a schematic side sectional view of a metal flat tube supported solid oxide fuel cell structure according to an embodiment of the present invention;
fig. 3 is a schematic cross-sectional view illustrating a structure of a metal flat tube supported solid oxide fuel cell according to an embodiment of the present invention;
fig. 4 is a schematic longitudinal cross-sectional view of the middle part of a metal flat tube supported solid oxide fuel cell/electrolytic cell structure prepared according to an embodiment of the present invention;
fig. 5 is a schematic longitudinal sectional view of the middle part of a metal flat tube supported solid oxide fuel cell/electrolytic cell structure prepared according to an embodiment of the present invention;
fig. 6 shows a structural diagram of a metal flat tube supported solid oxide fuel cell/electrolytic cell structure prepared according to an embodiment of the present invention;
fig. 7 is a schematic longitudinal sectional view showing a flat tube type fuel cell provided in the related art;
fig. 8 shows a schematic representation of void classification by porosity (fig. a) and a scanning electron microscope schematic representation of a dense structure prepared according to an example of the present invention (fig. b).
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below. The following examples are given for the detailed implementation and specific operation of the present invention, but the scope of the present invention is not limited to the following examples.
A metal supported Solid Oxide Fuel Cell (SOFC) is prepared on a porous metal, and the porous metal is connected with a metal connector. In order to prevent the fuel gas from leaking, it is necessary to perform a connection and sealing process between the porous metal support and the metal joint. In the conventional connection sealing method, the connection sealing is usually performed by using a welding technique in the contact area of the porous metal support and the metal connector. However, the SOFC operates at a temperature of 600-800 ℃, and at such a high temperature, the welded joint is not uniform in stress and composition, which results in poor sealing properties, and the sealing properties and oxidation resistance of the weld may affect the long-term stability of the cell, resulting in degradation of cell performance. The same problem exists with corresponding electrolytic cells.
As shown in figure 7, the flat tube type fuel cell of the existing solid oxide fuel cell adopts a flat tube-shaped anode, one side of the flat tube-shaped anode is fixedly connected with a connector, the other area is covered with a compact electrolyte, and the other side of the flat tube-shaped anode is covered with a cathode. This structure combines the advantages of flat cells and tubular cells. However, the ceramic anode is fragile, only one surface of the flat tube is utilized, and the volume power density of the battery is not high.
The invention provides a metal flat tube supported solid oxide fuel cell/electrolytic cell, which solves the problems because the structure is based on a metal flat tube support body, avoids the sealing and connection of a porous metal support body and a metal connector, and improves the volume power density of the cell.
In order to further understand the present invention, the present invention is further illustrated below with reference to specific examples, and since the electrolysis cell and the fuel cell are a pair of energy conversion devices with the same structure and the reverse operation, the embodiments of the present application are illustrated by taking the fuel cell as an example.
Referring to fig. 1, an embodiment of the present invention provides a metal flat tube support structure, which includes an open end (1-1), a porous structure (1-2), a closed end (1-3), and a fuel gas channel (1-4);
wherein, the open end (1-1) and the closed end (1-3) are respectively positioned at two ends of the porous structure (1-2); the fuel gas flow channel (1-4) is arranged inside the porous structure (1-2) and is used for fuel gas circulation; the closed end (1-3) is made of metal powder and is of a compact structure and used for sealing the first end of the fuel gas flow passage;
and the open end (1-1) comprises: a fuel gas inlet (1-5), a dense structure (1-6) and a fuel gas outlet (1-6); wherein, the fuel gas inlet (1-5) is used for introducing fuel gas; fuel gas outlets (1-6) for fuel gas outflow; the dense structures (1-6) are used to seal the second end of the fuel gas flow channel.
The distance between the upper plane and the lower plane of the metal flat tube supporting body structure provided by the embodiment of the invention is 3-20 mm, and the width value is 2 times larger than the distance value; and the length of the porous structure accounts for 50-90% of the total length of the metal flat tube support body. Wherein, the length refers to the distance between the edge of the closed end (1-3) and the edge of the open end (1-1), and the corresponding width is shown in figure 1.
The porosity of the porous structure (1-2) of the metal flat tube support body structure provided by the embodiment of the invention is 15-60%. The porosity is determined by the following steps: when the porosity is too small, the gas can not flow normally, and the performance of the battery is influenced; when the porosity is too large, the strength and the surface roughness of the porous metal cannot be ensured, the service life and the performance of the battery cannot be better, and the porosity of the compact part is less than 7 percent (the value basis of the range is as follows: when the value is less than the value, the state of a closed hole is achieved, namely, the gas can not flow, the effect of no leakage is achieved, and the sealing effect is achieved.
In the embodiment of the invention, the flat tube support body is prepared from the metal material, and the strength of the metal material is far higher than that of a ceramic material (namely, an anode support body in the prior art, as shown in fig. 7), namely, the flat tube support body has the advantage of high strength, the ceramic material is easy to crack in the use process of a battery, and the metal material is not easy to crack in the use process of the battery. Therefore, the mechanical property of the battery/electrolytic cell is effectively improved by adopting the metal flat tube support body to prepare the battery/electrolytic cell.
In the embodiment of the invention, the flat tube support body is prepared by adopting the metal material, the internal temperature of the battery is easy to be uniform even if the temperature rising speed is high due to high metal heat conductivity, and the metal has high strength and internal stress and is not easy to generate cracks. Therefore, the battery/electrolytic cell prepared by the metal flat tube support body can be started quickly. And the anode support body (made of ceramic material) is adopted, because the ceramic heat conduction is poor, if the temperature rise speed is too high, the local temperature is not uniform, and further the problem of cracking caused by stress is generated. In addition, the metal flat tube support body is prepared from the metal material, and the preparation process is simple (the integrated metal flat tube support body structure is obtained by roasting once), so that the battery/electrolytic cell prepared from the metal flat tube support body has the advantage of reducing the cost.
In the embodiment of the invention, the flat tube support body is prepared by adopting the metal material, the electric conductivity of the metal is superior to that of the ceramic used as the anode support body, and the strength of the metal is higher, so that the thicknesses of the anode, the cathode and the electrolyte of the battery/electrolytic cell in the application can be as small as possible (namely, a thin structural layer), when the thickness of the electrolyte is lower, the internal resistance of the battery can be effectively reduced, the current conduction efficiency is improved (the loss of the anode support body during current conduction is higher because the electric conductivity of the anode is lower than that of the metal), when the thickness of the electrode is lower, the polarization impedance of the electrode is reduced, the gas diffusion reaction is facilitated, and the purpose of saving energy is achieved while the performance. The polarization impedance refers to resistance of an electrode to a cell reaction. Therefore, the battery/electrolytic cell prepared by the metal flat tube support body has the advantage of improving the conductivity of the battery/electrolytic cell.
Fig. 2 is a schematic side sectional view of a metal flat tube supported solid oxide fuel cell structure according to an embodiment of the present invention. As shown in fig. 2, 2-1 is an open end, 2-3 is a closed end, 2-4 is a fuel gas flow channel, 2-5 is a fuel gas inlet, 2-6 is a dense structure, 2-7 is a fuel gas outlet, 2-8 is a dense structure, 2-9 is an anode, 2-10 is an electrolyte, and 2-11 is a cathode, wherein the porous structure 2-2 surrounded by the anode is not shown.
In an embodiment of the present invention, when the outer surface of the metal flat tube support sequentially covers the anode, the electrolyte, and the cathode from inside to outside, the positional relationship among the metal flat tube support, the anode, the electrolyte, and the cathode may be: the length of the anode is more than or equal to that of the porous structure so as to ensure the purpose of fully utilizing the gas flowing out of the porous structure; the length of the anode is less than that of the metal flat pipe support body so as to ensure that the compact electrolyte can completely cover the anode and contact with compact structures at two ends of the metal flat pipe support body to achieve the purpose of self-sealing.
In the embodiment of the invention, the length of the electrolyte is greater than that of the anode, so that the electrolyte can completely cover the anode; the length of the electrolyte is less than or equal to the length of the metal flat tube support body, when the length of the electrolyte is less than the length of the metal flat tube support body, the position relationship shown in fig. 2, fig. 3 and fig. 6 is obtained, when the length of the electrolyte is equal to the length of the metal flat tube support body, the length of the electrolyte only needs to be aligned with the length of the metal flat tube support body in the preparation process, the preparation method is the same, and details are not repeated in this embodiment.
In the embodiment of the invention, the length of the cathode is equal to that of the anode. It should be noted that the cathode length may be longer than the anode length, but the effective length is based on the shorter length.
Fig. 3 is a schematic cross-sectional view illustrating a structure of a metal flat tube supported solid oxide fuel cell according to an embodiment of the present invention;
as shown in fig. 3, 3-1 is an open end, 3-3 is a closed end, 2-4 is a fuel gas flow channel, 3-5 is a fuel gas inlet, 3-6 is a dense structure, 3-7 is a fuel gas outlet, 3-8 is a dense structure, 3-9 is an anode, 3-10 is an electrolyte, and 3-11 is a cathode, wherein the porous structure 3-2 surrounded by the anode is not shown. Since the structure of the battery is the same as that of the electrolytic cell, the related description is the same as that of fig. 2, and the description thereof is omitted.
Fig. 4 is a schematic longitudinal cross-sectional view of the middle part of a metal flat tube supported solid oxide fuel cell/electrolytic cell structure prepared according to an embodiment of the present invention;
as shown in fig. 4, 4-1 is a metal flat tube support, 4-2 is an anode, 4-3 is an electrolyte, 4-4 is a cathode, and 4-5 is a fuel gas flow channel.
In the metal flat tube supported solid oxide fuel cell/electrolytic cell provided by this embodiment, the cell anode or the electrolytic cell cathode covers the entire outer surface of the porous structure of the metal flat tube support, that is, the two side arc-shaped curved surfaces of the porous structure are included, so as to increase the effective area of the cell/electrolytic cell, and the cell cathode or the electrolytic cell anode also covers the outer surface of the electrolytic cell, and the length of the cell cathode or the electrolytic cell anode may be greater than or equal to the length of the cell anode or the electrolytic cell cathode.
Fig. 5 is a schematic longitudinal sectional view of the middle part of a metal flat tube supported solid oxide fuel cell/electrolytic cell structure prepared according to an embodiment of the present invention;
as shown in fig. 5, 5-1 is a metal flat tube support, 5-2 is an anode, 5-3 is an electrolyte, 5-4 is a cathode, and 5-5 is a fuel gas flow channel.
In the metal flat tube supported solid oxide fuel cell/electrolytic cell provided by this embodiment, the cell anode or the electrolytic cell cathode covers the upper plane and the lower plane of the porous structure of the metal flat tube support body, that is, the two side arc-shaped curved surfaces of the porous structure are not included, and the corresponding electrolyte covers the cell anode or the electrolytic cell cathode and also covers the remaining porous structure part, thereby achieving the purpose of sealing.
In this embodiment, the cell cathode or cell anode covers the entire electrolyte, but in practice, the cell cathode or cell anode may cover only the anode region, i.e. the length and width of the anode are equal, and the corresponding cathode area is equal to the anode area.
Fig. 6 shows a structural diagram of a metal flat tube supported solid oxide fuel cell/electrolytic cell structure prepared according to an embodiment of the present invention;
as shown in fig. 6, the metal flat tube supported solid oxide fuel cell/electrolytic cell structure provided by the embodiment of the present invention includes a metal support body, an anode, an electrolyte, and a cathode, where the metal flat tube supported solid oxide fuel cell structure has a blind hole at one end. The metal flat tube support body is internally provided with a fuel gas flow channel, fuel gas flows in from an inlet and flows out from an outlet, and the upper plane and the lower plane of the metal flat tube support body are wrapped with an anode, an electrolyte layer and a cathode.
In the embodiment of the invention, the pores in the porous structure of the metal flat tube support body with the porosity of 15-60% belong to through holes (shown as a picture a in figure 8), and the through holes can realize normal circulation of gas; in the embodiment of the invention, the compact structure of the metal flat pipe support body with the porosity of less than 7% and the pores in the compact structure belong to closed pores (as shown in a graph a in fig. 8), and gas cannot circulate in the closed pores, so that the purpose of preventing gas leakage is achieved, namely, the compact structure and the compact structure of the metal flat pipe support body belong to compact structures (as shown in a graph b in fig. 8), the pores in the compact structure belong to closed pores, the pores are not communicated with each other, a gas channel cannot be formed, and the purpose of sealing is achieved. Therefore, the dense structures at the two ends of the metal flat pipe supporting body and the dense structures wrap the porous structure in the middle part, and the self-sealing purpose is achieved.
The metal powder materials with the compact structure, the compact structure and the porous structure in the metal flat tube support body provided by the invention are the same metal powder material, the metal material at least comprises one of iron-chromium alloy, nickel-chromium alloy and pure chromium, and other metal materials meeting the preparation conditions can be selected during specific implementation. Therefore, the metal flat tube support body provided by the invention can be prepared in one step in a powder metallurgy mode, so that the metal flat tube support body with the fuel gas flow channel arranged inside and having the integrated structure characteristic can be obtained, and the support body has no connection interface and does not need to adopt connection technologies such as welding and the like.
In order to make the present invention more comprehensible to those skilled in the art, the metal flat tube support, the cell/electrolytic cell, and the cell stack structure of the present invention are described in the following by specific examples.
Example 1
Referring to fig. 1, in the present embodiment, an iron-nickel alloy is used as a material for a support of a metal flat tube, a powder metallurgy sintering process is adopted to form the support of the metal flat tube, the thickness of the flat tube (i.e., the distance between an upper plane and a lower plane) is 0.8cm, the length and the width of the upper plane area and the lower plane area are 15cm × cm, the middle section of the flat tube is porous, the porosity is 30%, both ends are dense, and a serpentine gas flow channel is arranged inside the flat tube, wherein 1cm of a blind hole end (i.e., a closed end) of the flat tube is a dense area, 2cm of an open hole end is a dense area, and 12cm of the middle is a porous structure.
Example 2
In the embodiment, pure chromium is used as a material of a metal flat tube support body, powder metallurgy is adopted to prepare the metal flat tube support body, the thickness of the flat tube is 1.2cm, the length and the width of upper and lower plane areas are respectively 6cm and 24cm, the middle section of the flat tube is porous, the porosity is 15%, the two ends are compact, and a gas flow channel is arranged in the flat tube, wherein a blind hole end 1cm of the flat tube is a compact area, an opening section 3cm is a compact area, the middle 20cm is a porous structure, a Ni/GDC cathode is sprayed to wrap the middle section porous support body, a BZCY electrolyte is sprayed to wrap the cathode and all exposed porous metal support bodies, L SM anodes are respectively screen-printed on two planes of the flat tube, an electrolytic cell is prepared after sintering, and the.
Example 3
In the embodiment, iron-nickel alloy is used as a material of a metal flat tube support body, the metal flat tube support body is formed by powder metallurgy sintering, the thickness of a flat tube is 1.5cm, the length and the width of an upper plane region and a lower plane region are respectively 8cm and 30cm, the flat tube metal support body with a flow channel and compact two ends is adopted, wherein 1cm at the two ends is a compact region, 28cm in the middle is a porous structure, and the porosity is 40%.
Example 4
The method comprises the steps of adopting powder metallurgy sintering to form a FeCr metal flat tube support body containing 95% of Cr, enabling the thickness of the flat tube to be 0.8cm, enabling the length and the width of an upper plane area and a lower plane area to be 25cm × 6cm, enabling the middle section of the flat tube to be porous, enabling the porosity to be 60%, enabling two ends to be compact, and enabling a gas flow channel to be arranged inside the flat tube, enabling 1cm of a blind hole end of the flat tube to be a compact area, enabling a hole section to be 3cm to be a compact area, enabling the middle 21cm to be of a porous structure, preparing a Ni/GDC anode on the metal flat tube support body by adopting a tape casting method, covering the porous structure, preparing a ScSZ electrolyte by adopting tape casting, completely wrapping the anode, preparing L SM and L SCF.
Example 5
The support body of the FeCr metal flat tube containing 25 percent of Cr is sintered and molded by adopting powder metallurgy, the thickness of the flat tube is 1.2cm, the length and the width of the upper plane area and the lower plane area are 50cm × 6cm, the middle section of the flat tube is porous, the porosity is 30 percent, the two ends are compact, a gas flow passage is arranged in the flat tube, wherein the flat tube is provided with a gas flow passageThe blind hole end 1cm is a compact area, the open hole section 3cm is a compact area, and the middle 46cm is a porous structure. Preparing Ni/GDC anode on the metal flat tube support body by adopting a tape casting method, covering a porous structure, and then sintering at 1000 ℃. Preparation of Co by tape casting2O3And (3) completely wrapping the anode by using the doped GDC and ScSZ composite electrolyte, preparing L SM and L SCF composite cathodes on the electrolyte by using a screen printing method, and sintering at 1050 ℃ in Ar protective atmosphere to finish the preparation of the single cell.
Then, a stack comprising two or more prepared solid oxide fuel cells may be further prepared.
In the above examples, Ni is Ni, Cr is Cr, YSZ is yttria-stabilized zirconia, L SCF is lanthanum strontium cobalt iron, L SM is strontium lanthanum manganate, ScSZ is zirconia-based, Co is2O3Cobaltous oxide, GDC gadolinium doped cerium oxide, BZCY barium zirconium cerium yttrium. It should be noted that the cathode, the anode and the electrolyte materials selected in the present invention can be selected from commonly used materials, which are not limited in the present invention, and in the actual preparation process, the specific coverage areas of the anode, the electrolyte and the cathode can be adjusted according to the actual requirements, which is not limited in the present invention.
For simplicity of explanation, the method embodiments are described as a series of acts or combinations, but those skilled in the art will appreciate that the present invention is not limited by the order of acts, as some steps may occur in other orders or concurrently in accordance with the invention. Further, those skilled in the art will appreciate that the embodiments described in the specification are preferred embodiments and that the acts and elements referred to are not necessarily required to practice the invention.
The metal flat tube support, the battery/electrolytic cell and the battery stack structure provided by the invention are described in detail, specific examples are applied in the description to explain the principle and the implementation mode of the invention, and the description of the examples is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims (10)

1. A metal flat tube support body structure is characterized in that the structure is provided with a first end, a second end and a support main body;
the first end is a closed end, the second end is an open end, the first end is opposite to the second end, and the first end and the second end are positioned on two sides of the support main body;
the support main body is of a porous structure, and a fuel gas flow channel is arranged in the support main body and used for fuel gas circulation;
the closed end is of a compact structure and is used for sealing the first end of the fuel gas flow channel;
the opening end is of a compact structure and is used for sealing the second end of the fuel gas flow passage, and a fuel gas inlet and a fuel gas outlet are formed in the compact structure; the fuel gas inlet is used for introducing fuel gas; the fuel gas outlet is used for fuel gas outflow.
2. The structure of claim 1, wherein the metal flat tube support structure has an upper plane and a lower plane, and the distance between the upper plane and the lower plane is 3mm to 20 mm; the width of the metal flat tube support body structure is more than 2 times of the distance.
3. The structure of claim 1, wherein the length of the support body is 50-90% of the length of the metal flat tube support body structure.
4. The structure of claim 1, wherein the support body has a porosity of 15-60%.
5. The structure of claim 1, wherein the metal flat tube support structure is prepared by a method comprising at least powder metallurgy.
6. The structure of claim 1, wherein the metal flat tube support structure is made of a material comprising at least one of iron-chromium alloy, iron-nickel alloy and pure chromium.
7. A metal flat tube supported solid oxide fuel cell/electrolyser structure, characterized in that it comprises: the metal flat tube support structure of any one of claims 1 to 6, an anode, an electrolyte and a cathode;
the battery anode or the electrolytic cell cathode covers the support main body of the metal flat tube support body structure, wherein the length of the battery anode or the electrolytic cell cathode is greater than or equal to that of the support main body and is smaller than that of the metal flat tube support body structure;
the electrolyte covers the battery anode or the electrolytic cell cathode, wherein the length of the electrolyte is greater than that of the battery anode or the electrolytic cell cathode and is less than or equal to that of the metal flat tube support structure, and the electrolyte is respectively contacted with the closed end and the open end of the metal flat tube support structure;
the battery cathode or the electrolytic cell anode covers the electrolyte, and the area of the battery cathode or the electrolytic cell anode is larger than or equal to that of the battery anode or the electrolytic cell cathode.
8. The battery/electrolytic cell structure of claim 7,
the battery anode or the electrolytic battery cathode covers the upper plane and the lower plane of the support main body of the metal flat pipe support body structure; or
The battery anode or the electrolytic battery cathode covers the upper surface and the lower surface of the support main body of the metal flat pipe support body structure; or
The battery anode or the electrolytic cell cathode covers the whole outer surface of the support main body of the metal flat tube support body structure.
9. The battery/cell structure of claim 7, wherein the anode, the electrolyte layer and the cathode are covered by spraying or sintering.
10. A solid oxide fuel cell stack structure, comprising: a solid oxide fuel cell stack structure of two or more solid oxide fuel cell structures as claimed in any of the preceding claims 7-9.
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