Reversible solid oxide battery with structural stability and preparation method thereof

Abstract

The invention provides a reversible solid oxide battery with structural stability and a preparation method thereof, the reversible solid oxide battery comprises a hydrogen electrode layer, an electrolyte layer, a barrier layer and an oxygen electrode layer which are stacked from bottom to top, the oxygen electrode layer comprises a plurality of electrode units, and a gap exists between two adjacent electrode units; the oxygen electrode layer of the reversible solid oxide battery is designed into a plurality of electrode units which are arranged at intervals, and the geometric isotropy of a single electrode unit enables the electrode unit to uniformly disperse thermal stress and mechanical stress when the electrode unit is stressed, so that local overload is avoided; from the aspect of mass transfer, gaps between adjacent electrode units serve as oxygen release rapid channels, the oxygen partial pressure gradient can be effectively reduced, and the oxygen diffusion efficiency is improved. Through the synergistic effect of the two design aspects, the layering risk caused by uneven stress and oxygen partial pressure difference on the interface of the oxygen electrode layer and the barrier layer can be greatly reduced, so that the reliability of the solid oxide electrolytic tank is remarkably improved, and the service life of the solid oxide electrolytic tank is remarkably prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of reversible solid oxide cells, in particular to a reversible solid oxide cell with structural stability and a preparation method thereof. BACKGROUND

[0002] With the increasing global energy demand and the growing environmental problems, the demand for renewable energy is becoming more and more urgent. Reversible solid oxide cells (RSOC) are a kind of high-efficiency and clean energy conversion devices, which have broad application prospects in distributed power generation, new energy vehicles and other fields due to their wide fuel adaptability, all-solid-state structure and high energy conversion efficiency. Reversible solid oxide cells (RSOC) are composed of oxygen electrodes, barrier layers, electrolytes, hydrogen electrodes, and have two working modes of solid oxide electrolysis cells (SOEC) and solid oxide fuel cells (SOFC). The SOEC mode can convert electrical energy into chemical energy in the form of hydrogen, syngas, methane and other fuels, and the SOFC mode can effectively convert the chemical energy in the fuel into electrical energy.

[0003] However, the long-term performance stability of RSOC and the high manufacturing cost limit its commercialization process. The oxygen electrode (i.e. the cathode in the SOFC mode and the anode in the SOEC mode) is one of the key components of RSOC, and its performance directly affects the efficiency and stability of the entire cell. However, the traditional flat plate cell oxygen electrode design usually adopts a whole square structure, which faces the following challenges during long-term operation, especially in the environment of frequent mode conversion and high temperature thermal cycling: (1) problems caused by thermal stress: the working environment of RSOC in SOFC and SOEC modes is different, and the change of temperature gradient and chemical environment is easy to cause the accumulation of thermal stress in the oxygen electrode layer, and then cause delamination or cracking, reducing the long-term stability of the cell. (2) Limited oxygen transport: in the traditional oxygen electrode design, oxygen mainly diffuses to the reaction active site through the electrode gap, but when running at high current density, the limited oxygen diffusion may cause uneven oxygen partial pressure, thereby reducing the electrochemical activity of the electrode and accelerating material degradation. The low oxygen diffusion efficiency in SOEC mode (electrolysis cell) will also cause the oxygen electrode and the barrier layer to have too high oxygen partial pressure, causing delamination, which seriously affects the material performance. (3) Too much structural rigidity, difficult to relieve stress concentration: the traditional square area structure is not easy to deform when stressed, and lacks an effective stress release mechanism, making the electrode more prone to mechanical damage during long-term cycling.

[0004] Therefore, it is crucial to improve the overall structural strength of the battery, establish an effective stress release mechanism, improve the oxygen diffusion efficiency, and alleviate the stratification of the oxygen electrode and the electrolyte in order to maintain the stability of the electrochemical performance of the oxygen electrode. Existing methods to alleviate stratification include introducing a barrier layer between the oxygen electrode and the electrolyte to reduce the risk of stratification caused by interfacial thermal stress and chemical mismatch, but long-term operation may still lead to interface degradation, and ion diffusion between different materials may lead to the formation of new phases, affecting the interfacial bonding strength, and stratification may still occur between the oxygen electrode and the barrier layer. Using nano-scale catalytic materials or designing porous structures to improve interfacial bonding and reduce stress concentration is also a method, but nanoparticles are prone to agglomeration and aging at high temperatures, resulting in a decrease in catalytic activity, and the gap structure may reduce mechanical strength and increase the brittleness of the electrode, making it more susceptible to thermal cycle damage. Summary of the Invention

[0005] In response to the above-mentioned defects or improvement needs of the prior art, the present invention provides a reversible solid oxide battery with structural stability and a preparation method thereof, so as to solve the technical problem that the reversible solid oxide battery prepared by the prior art has reduced performance stability due to the accumulation of thermal stress inside the oxygen electrode layer.

[0006] To solve the above technical problems, the present invention first provides a reversible solid oxide battery with structural stability, the reversible solid oxide battery comprising a hydrogen electrode layer, an electrolyte layer, a barrier layer and an oxygen electrode layer stacked from bottom to top; The oxygen electrode layer includes a plurality of electrode units, and there is a gap between two adjacent electrode units.

[0007] Preferably, the plurality of electrode units are arranged in an array, and the distance between two adjacent electrode units is equal.

[0008] Preferably, the orthographic projection shape of each electrode unit on the hydrogen electrode layer includes any one of a polygon, a circle, an ellipse and a water drop shape.

[0009] Preferably, the orthographic projection shape of the hydrogen electrode layer on the barrier layer is a regular quadrilateral; the orthographic projection shape of each electrode unit on the hydrogen electrode layer is a regular quadrilateral.

[0010] Preferably, the distance between two adjacent electrode units is 150-250 μm.

[0011] Preferably, the materials of the hydrogen electrode layer and the electrolyte layer include Ni-YSZ material, the material of the barrier layer includes gadolinium oxide doped cerium oxide material, and the material of the oxygen electrode layer includes La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ material, 0≤δ≤0.5, δ represents oxygen vacancies.

[0012] Accordingly, the present invention also provides a method for preparing a reversible solid oxide battery with structural stability as described in any one of the above items, comprising: S10, preparing a whole block of hydrogen electrode material by a tape casting method and then cutting it to obtain a hydrogen electrode layer; S20, forming an electrolyte layer on the hydrogen electrode layer using a screen printing process; S30, forming a barrier layer on the electrolyte layer using a screen printing process; S40, forming an oxygen electrode layer on the electrolyte layer by screen printing, wherein the oxygen electrode layer includes a plurality of electrode units, and a gap exists between two adjacent electrode units.

[0013] Preferably, in step S40: the plurality of electrode units are arranged in an array, and the distance between two adjacent electrode units is 150-250 μm.

[0014] Preferably, the orthographic projection shape of the hydrogen electrode layer on the barrier layer is a regular quadrilateral; the orthographic projection shape of each electrode unit on the hydrogen electrode layer is a regular quadrilateral.

[0015] Preferably, the materials of the hydrogen electrode layer and the electrolyte layer include Ni-YSZ material, the material of the barrier layer includes gadolinium oxide doped cerium oxide material, and the material of the oxygen electrode layer includes La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ material, 0≤δ≤0.5, δ represents oxygen vacancies.

[0016] The beneficial effects of the present invention are as follows: Different from the prior art, the present invention provides a reversible solid oxide cell with structural stability and a preparation method thereof, wherein the reversible solid oxide cell comprises a hydrogen electrode layer, an electrolyte layer, a barrier layer and an oxygen electrode layer stacked from bottom to top, wherein the oxygen electrode layer comprises a plurality of electrode units, and there is a gap between two adjacent electrode units; the present invention designs the oxygen electrode layer of the reversible solid oxide cell into a plurality of spaced electrode units, based on geometric principles, the geometric isotropy of a single electrode unit enables it to evenly disperse thermal stress and mechanical stress when subjected to force, thereby avoiding local overload; from the perspective of mass transfer, the gap between adjacent electrode units acts as a fast channel for oxygen release, which can effectively reduce the oxygen partial pressure gradient and accelerate the oxygen diffusion efficiency. The synergistic effect of these two aspects of the design can greatly reduce the risk of delamination caused by uneven stress and oxygen partial pressure difference at the interface between the oxygen electrode layer and the barrier layer, thereby significantly improving the reliability and service life of the solid oxide electrolytic cell, and providing an innovative and effective technical means for solving the problem of interface delamination caused by high oxygen partial pressure and uneven stress in the development and application of high-performance solid oxide electrolytic cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic cross-sectional view of a reversible solid oxide battery with structural stability provided in Example 1 of the present invention; Figure 2 A top view of the oxygen electrode layer in the reversible solid oxide battery with structural stability provided in Example 1 of the present invention; Figure 3 A flow chart of a method for preparing a reversible solid oxide battery with structural stability provided in Example 1 of the present invention; In the accompanying drawings: 100 - reversible solid oxide cell; 10 - hydrogen electrode layer; 20 - electrolyte layer; 30 - barrier layer; 40 - oxygen electrode layer; 401 - electrode unit; 402 - gap. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] In response to the above-mentioned defects or improvement needs of the prior art, the technical problem to be solved by the present invention is to provide a reversible solid oxide battery based on quadrilateral stability, by improving the overall structural strength of the battery, establishing an effective stress release mechanism, improving the oxygen diffusion efficiency, thereby reducing the oxygen partial pressure between the oxygen electrode and the barrier layer, preventing stratification problems, and improving the electrochemical performance of the oxygen electrode to improve the long-term stability of the reversible solid oxide battery.

[0020] The technical solutions of the present invention will be described in further detail below with reference to specific examples. It should be understood that the following examples are merely illustrative and explain the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are encompassed within the scope of protection intended by the present invention. Unless otherwise stated, the raw materials and reagents used in the following examples are all commercially available products or can be prepared by known methods.

[0021] Example 1: See also Figure 1 as well as Figure 2 , Figure 1 A schematic cross-sectional view of a reversible solid oxide battery 100 with structural stability provided in Example 1 of the present invention; Figure 2A top view of the oxygen electrode layer in the structurally stable reversible solid oxide cell 100 provided in Example 1 of the present invention; wherein the reversible solid oxide cell 100 includes a hydrogen electrode layer 10, an electrolyte layer 20, a barrier layer 30, and an oxygen electrode layer 40 stacked from bottom to top; The oxygen electrode layer 40 includes a plurality of electrode units 401 , and a gap 402 exists between two adjacent electrode units 401 .

[0022] Specifically, the reversible solid oxide battery 100 is designed with a stacked structure of a hydrogen electrode layer 10, an electrolyte layer 20, a barrier layer 30 and an oxygen electrode layer 40, especially dividing the oxygen electrode layer 40 into multiple electrode units 401 with gaps 402. The geometric isotropy of a single electrode unit 401 is used to achieve uniform dispersion of thermal stress and mechanical stress, avoiding local stress concentration; the gaps 402 between adjacent electrode units 401 serve as fast channels for oxygen release, which can reduce the oxygen partial pressure gradient and improve the oxygen diffusion efficiency, thereby reducing the risk of delamination at the interface between the oxygen electrode layer 40 and the barrier layer 30 due to uneven stress and oxygen partial pressure differences, effectively improving the structural stability, reliability and service life of the battery.

[0023] In this embodiment 1, the hydrogen electrode layer 10 is the core site where the fuel oxidation reaction occurs. Taking hydrogen as an example, H2+O2 occurs here. - →H2O+2e - The oxidation reaction releases electrons and produces oxygen ions. The electrons are conducted through the electrodes to form an electric current, and the oxygen ions migrate to the oxygen electrode to participate in subsequent reactions. Its structure composed of high electronic conductivity materials can efficiently collect and transmit electrons to ensure a smooth current circuit. The porous structure design provides a channel for fuel diffusion, promotes full contact between the fuel and the electrode-electrolyte interface, and is conducive to the discharge of water vapor generated by the reaction. In addition, the hydrogen electrode layer 10 also plays a mechanical supporting role, cooperating with other components to maintain the stability of the battery structure, and with its own good thermal stability and chemical stability, it can resist thermal cycling stress and chemical corrosion.

[0024] In this embodiment 1, the electrolyte layer 20 conducts oxygen ions at high temperatures to form a charge transfer channel. At the same time, with its high electronic insulation and dense structure, it isolates the electronic conduction of the electrodes on both sides from the gas cross-diffusion, avoiding short circuits and efficiency losses. As a thin sheet-like ceramic layer, it plays a mechanical support role, matching the thermal expansion coefficients of other components to maintain the stability of the battery structure. The interface between the electrolyte layer 20 and the electrode can expand the three-phase reaction area and improve the efficiency of the electrochemical reaction.

[0025] Specifically, the hydrogen electrode layer 10 and the electrolyte layer 20 are both made of Ni-YSZ (Ni-Yttria-Stabilized Zirconia) material.

[0026] In this first embodiment, the core function of barrier layer 30 is to ensure long-term, reliable battery operation through physical isolation and chemical stability mechanisms. On the one hand, it prevents metal elements (such as Ni) in hydrogen electrode layer 10 (e.g., Ni-YSZ material) from diffusing into electrolyte layer 20, thereby preventing degradation of electrolyte ion conductivity and the formation of an interfacial reaction layer due to interdiffusion of elements. On the other hand, its high electronic insulation properties block unintended electron conduction pathways, preventing internal short circuits in the battery. Simultaneously, as a dense ceramic layer, it blocks direct contact between the fuel gas and the electrolyte, thus preventing chemical degradation of the electrolyte in a reducing atmosphere. Furthermore, barrier layer 30 buffers the difference in thermal expansion coefficients between the electrode and electrolyte, enhances interlayer bonding through nanoscale interface modification, inhibits interfacial delamination during thermal cycling, and provides a stable three-phase reaction region for electrochemical reactions, thereby improving the battery's power density and service life.

[0027] Specifically, the material of the barrier layer 30 includes gadolinium oxide doped cerium oxide material.

[0028] In this embodiment 1, the oxygen electrode layer 40 is the core functional layer for realizing the oxygen reduction reaction and the oxygen evolution reaction in the reversible solid oxide battery 100. Its function is realized through multi-dimensional synergy: at the electrochemical reaction level, the porous structure of the oxygen electrode layer 40 adsorbs oxygen in the air and dissociates it into oxygen ions (O 2- ), after obtaining electrons through the electrochemical reaction, it migrates to the opposite side through the electrolyte layer 20, and at the same time serves as an electron transmission channel to introduce electrons from the external circuit into the reaction site; at the material level, it uses highly catalytically active perovskite oxides, which have both good oxygen ion-electron mixed conductivity and resistance to high-temperature sintering to ensure the stability of the reaction interface; in addition, the oxygen electrode layer 40 needs to maintain chemical stability in an oxidizing atmosphere to avoid catalytic activity attenuation caused by element volatilization or phase change. Its performance directly affects the battery's charge and discharge efficiency and long-term reliability.

[0029] Specifically, the oxygen electrode layer 40 includes a plurality of electrode units 401 arranged in an array, and a gap 402 exists between two adjacent electrode units 401; wherein, the oxygen electrode layer 40 is designed with a plurality of electrode units 401 arranged in an array and with adjacent gaps 402. On the one hand, the geometric symmetry of the unit is used to achieve uniform dispersion of thermal stress and mechanical stress, thereby reducing structural damage caused by stress concentration; on the other hand, the gap 402 serves as a fast channel for oxygen transmission, effectively reducing the oxygen partial pressure gradient, accelerating oxygen diffusion, and improving the efficiency of oxygen reduction / precipitation reactions; at the same time, the structure can also expand the three-phase reaction interface area, reduce the interface impedance, and enhance the anti-carbon deposition ability. By optimizing material matching and preparation process, the power density and long-term operation stability of the reversible solid oxide battery 100 are significantly improved.

[0030] Specifically, the positive projection shape of each electrode unit 401 on the hydrogen electrode layer 10 includes any one of a polygon, a circle, an ellipse and a teardrop shape; among them, the polygon expands the three-phase reaction interface through a regular array, the circle and the ellipse use a symmetrical structure to uniformly disperse thermal stress, and the teardrop shape optimizes the oxygen diffusion path with its unique morphology. These shapes can be combined with material properties and preparation processes to achieve stress dispersion, improve mass transfer efficiency and interface expansion, providing multiple options for performance optimization of the reversible solid oxide battery 100.

[0031] In this embodiment 1, the orthographic projection shape of the hydrogen electrode layer 10 on the barrier layer 30 is a regular quadrilateral; the orthographic projection shape of each electrode unit 401 on the hydrogen electrode layer 10 is a regular quadrilateral; wherein, this regular geometric design has multiple synergistic advantages: from the perspective of structural matching, the regular quadrilateral projection enables the hydrogen electrode layer 10 and the barrier layer 30 to be precisely aligned edge to edge, uniformly distributing the interlayer thermal stress through geometric symmetry, and reducing the local stress concentration caused by shape dislocation; the regular quadrilateral projection of the oxygen electrode unit 401 echoes the shape of the hydrogen electrode layer 10, and an array network of "regular quadrilateral unit-gap 402" can be constructed, and adjacent electrode units The gap 402 of element 401 forms a straight channel perpendicular to the electrode surface, which significantly reduces the oxygen diffusion resistance. At the same time, more three-phase reaction interfaces can be formed at the corners of the regular quadrilateral, which increases the reaction active sites by about 30% compared with the circular structure. From the perspective of preparation technology, the regular quadrilateral projection facilitates high-precision processing using extrusion molding or template methods. For example, the hydrogen electrode layer 10 blank is extruded through a square die, and then a proportional regular quadrilateral unit array is formed on the oxygen electrode layer 40 using photolithography technology to ensure that the size matching accuracy between each layer reaches ±5μm. This regular geometric design synergistically improves the structural stability, mass transfer efficiency and interface reaction kinetics of the battery.

[0032] Specifically, the material of the oxygen electrode layer 40 includes La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ(LSCF) material, 0≤δ≤0.5, δ represents oxygen vacancies; the spacing between two adjacent electrode units 401 is 150~250μm, preferably 200μm; wherein, the oxygen vacancy adjustability of LSCF enables it to achieve high oxygen ion conduction and catalytic activity through dynamic changes in δ at high temperatures, and the spacing of 150~250μm can not only serve as a "straight-through channel" for oxygen diffusion, reducing the oxygen partial pressure gradient and improving the diffusion efficiency, but also buffer the mechanical stress in the thermal cycle (such as the thermal expansion difference between the LSCF material and the electrolyte layer 20) through the geometric gap 402, avoiding interface stratification; in addition, this spacing range cooperates with the oxygen vacancy conduction characteristics of LSCF to expand the three-phase reaction interface area, reduce the interface impedance, and ultimately achieve optimization of the power density and long-term stability of the reversible solid oxide battery 100.

[0033] See also Figure 3 , Figure 3 A flow chart of a method for preparing a reversible solid oxide battery 100 with structural stability provided in Example 1 of the present invention; wherein the above-mentioned preparation method comprises: S10, preparing a whole block of hydrogen electrode material by a tape casting method and then cutting it to obtain a hydrogen electrode layer 10; S20, forming an electrolyte layer 20 on the hydrogen electrode layer 10 by screen printing; S30, forming a barrier layer 30 on the electrolyte layer 20 by screen printing; S40 , forming an oxygen electrode layer 40 on the electrolyte layer 20 by screen printing. The oxygen electrode layer 40 includes a plurality of electrode units 401 , and a gap 402 exists between two adjacent electrode units 401 .

[0034] In the above preparation method, the material of the hydrogen electrode layer 10 is the reversible solid oxide battery 100 hydrogen electrode material required for the research, such as common hydrogen electrode materials such as Ni-YSZ. The whole hydrogen electrode material is prepared by the casting method, and is cut into the regular quadrilateral designed by the present invention according to the requirements of its own test and sintered.

[0035] In the above preparation method, the material of the electrolyte layer 20 is a common electrolyte material, such as yttria-stabilized zirconia, etc., which can be prepared by a screen printing process. A screen with a regular quadrilateral gap 402 is used to print the electrolyte layer 20 of a suitable thickness on the prepared hydrogen electrode layer 10, and then sintered to densify it.

[0036] In the above preparation method, the material of the barrier layer 30 is a common barrier material, such as gadolinium oxide doped cerium oxide, etc., which can be prepared by a screen printing process. A barrier layer 30 of appropriate thickness is printed on the prepared electrolyte layer 20 using a screen with a regular quadrilateral gap 402, and then sintered to densify it.

[0037] In the above preparation method, the material of the oxygen electrode layer 40 is the reversible solid oxide battery 100 oxygen electrode material required for the research, such as LSCF material and other oxygen electrode materials, which is customized to have multiple regular quadrilaterals connected with each other and with a gap 402 of 150~250μm (preferably 200μm) between them. Using the screen printing process, the oxygen electrode of appropriate thickness is printed on the prepared barrier layer 303 and then sintered to form a honeycomb structure of multiple regular quadrilaterals, and the oxygen electrode layer 40 has a gap 402 of 150~250μm between each other.

[0038] When the reversible solid oxide cell 100 is tested in the SOFC mode, oxygen (O2) can enter through the gap 402 at the top of the regular quadrilateral in the oxygen electrode layer 40, or enter from the side gap 402 of the oxygen electrode layer 40 through the gap 402 provided. Compared with conventional cells without gaps 402, the oxygen absorption efficiency can be improved, especially under high current test conditions, which can alleviate the performance degradation caused by insufficient oxygen supply. Oxygen (O2) receives electrons at the oxygen electrode layer 40 to form oxygen ions (O 2- ), oxygen ions (O 2- ) is transferred to the electrolyte layer 20 through the barrier layer 30, and then moves to the hydrogen electrode layer 10 through the electrolyte layer 20. Hydrogen (H2) reacts with oxygen ions (O 2- ) reacts to produce water (H2O) and releases electrons to flow into the external circuit. The overall reaction is as follows: 2H2 + O2 = H2O, that is, hydrogen and oxygen undergo a redox reaction to produce water.

[0039] When the reversible solid oxide cell 100 is tested in the SOEC mode, water (H2O) is reduced at the hydrogen electrode layer 10 to generate hydrogen gas (H2) and oxygen ions (O 2- ), oxygen ions (O 2- ) moves through the hydrogen electrode layer 10 to the electrolyte layer 20, then passes through the electrolyte layer 20 to the barrier layer 30, and finally passes through the barrier layer 30 to the oxygen electrode layer 40. The oxygen ions (O 2- ) In the oxygen electrode layer 40, electrons are released to form oxygen (O2). The oxygen (O2) can be discharged through the top surface gap 402 of the regular quadrilateral of the oxygen electrode layer 40 or through the side gaps 402 provided in the oxygen electrode layer 40. Compared with conventional batteries, this improves the oxygen release efficiency and effectively reduces the oxygen partial pressure, preventing insufficient oxygen release. The increased oxygen partial pressure leads to excessive oxygen partial pressure at the interface between the oxygen electrode layer 40 and the barrier layer 30, causing delamination.

[0040] The structure of the reversible solid oxide battery 100 based on quadrilateral stability in this embodiment 1 does not have additional requirements on the materials of the original reversible solid oxide battery 100, and is applicable to reversible solid oxide batteries 100 using various materials as the oxygen electrode layer 40, barrier layer 30, electrolyte layer 20 and hydrogen electrode layer 10.

[0041] Furthermore, the overall design of the regular quadrilateral structure can enhance the structural strength of the entire battery. By utilizing the high symmetry (isotropy) of the regular quadrilateral, when subjected to external force, the load can be evenly transmitted through multiple symmetrical sides, thus avoiding local overload. At the same time, the provided gap 402 can buffer the expansion stress of the oxygen electrode layer 40 caused by temperature changes, thereby establishing a more effective stress release mechanism.

[0042] In summary, the present invention provides a fabrication technology for a reversible solid oxide cell 100 based on enhancing the structural stability of the oxygen electrode layer 40. This technology aims to address the problems of high and unevenly distributed oxygen partial pressure, concentrated mechanical stress, and easy delamination in the oxygen electrode layer 40 of conventional planar SOEC cells during service. The structure comprises multiple electrode units 401 (oxygen electrode regions) in the shape of regular quadrilaterals, an electrolyte layer 20, and a barrier layer 30, interconnected by the quadrilateral boundaries. The oxygen electrode layer 40 typically features a honeycomb arrangement of multiple regular quadrilateral units, with gaps 402 of 150 to 250 μm between adjacent boundaries. The geometric isotropic distribution of thermal and mechanical stresses by the regular quadrilaterals allows for the gaps 402 to act as rapid oxygen release pathways, reducing the oxygen partial pressure gradient and improving oxygen diffusion efficiency. This effectively reduces the risk of delamination at the interface between the oxygen electrode layer 40 and the barrier layer 30. The multi-unit partitioned oxygen electrode layer 40 design of the present invention can significantly improve the reliability and service life of the reversible solid oxide battery 100, provide an effective means to alleviate the interface stratification problem caused by high oxygen partial pressure and uneven stress, and is suitable for the development and application of high-performance reversible solid oxide batteries 100.

[0043] It should be noted that the above embodiments all belong to the same inventive concept, and the description of each embodiment has its own focus. For any details not described in individual embodiments, reference may be made to the description in other embodiments.

[0044] The above embodiments merely illustrate the implementation methods of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A reversible solid oxide battery with structural stability, characterized in that: The reversible solid oxide battery comprises a hydrogen electrode layer, an electrolyte layer, a barrier layer and an oxygen electrode layer stacked from bottom to top; The oxygen electrode layer includes a plurality of electrode units, and a gap exists between two adjacent electrode units.

2. The reversible solid oxide battery with structural stability according to claim 1, characterized in that: The plurality of electrode units are arranged in an array, and the distance between two adjacent electrode units is equal.

3. The reversible solid oxide battery with structural stability according to claim 2, characterized in that: The orthographic projection shape of each of the electrode units on the hydrogen electrode layer includes any one of a polygonal shape, a circular shape, an elliptical shape, and a water drop shape.

4. The reversible solid oxide battery with structural stability according to claim 3, characterized in that: The orthographic projection shape of the hydrogen electrode layer on the barrier layer is a regular quadrilateral; the orthographic projection shape of each of the electrode units on the hydrogen electrode layer is a regular quadrilateral.

5. The reversible solid oxide battery with structural stability according to claim 2, characterized in that: The distance between two adjacent electrode units is 150-250 μm.

6. The reversible solid oxide battery with structural stability according to claim 1, characterized in that: The materials of the hydrogen electrode layer and the electrolyte layer both include Ni-YSZ material, the material of the barrier layer includes gadolinium oxide doped cerium oxide material, and the material of the oxygen electrode layer includes La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ material, 0≤δ≤0.5, δ represents oxygen vacancies.

7. A method for preparing a reversible solid oxide battery with structural stability according to any one of claims 1 to 6, characterized in that: include: S10, preparing a whole block of hydrogen electrode material by a tape casting method and then cutting it to obtain the hydrogen electrode layer; S20, forming the electrolyte layer on the hydrogen electrode layer by a screen printing process; S30, forming the barrier layer on the electrolyte layer by a screen printing process; S40, forming the oxygen electrode layer on the electrolyte layer by screen printing, wherein the oxygen electrode layer includes a plurality of electrode units, and a gap exists between two adjacent electrode units.

8. The method for preparing a reversible solid oxide battery with structural stability according to claim 7, characterized in that: In the step S40 , the plurality of electrode units are arranged in an array, and a distance between two adjacent electrode units is 150-250 μm.

9. The method for preparing a reversible solid oxide battery with structural stability according to claim 7, characterized in that: The orthographic projection shape of the hydrogen electrode layer on the barrier layer is a regular quadrilateral; the orthographic projection shape of each of the electrode units on the hydrogen electrode layer is a regular quadrilateral.

10. The method for preparing a reversible solid oxide battery with structural stability according to claim 7, characterized in that: The materials of the hydrogen electrode layer and the electrolyte layer both include Ni-YSZ material, the material of the barrier layer includes gadolinium oxide doped cerium oxide material, and the material of the oxygen electrode layer includes La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ material, 0≤δ≤0.5, δ represents oxygen vacancies.

Images