A foamed metal current collector assembly and a solid oxide fuel cell stack

Abstract

This invention discloses a foamed metal current collector assembly and a solid oxide fuel cell stack. The foamed metal current collector assembly is applied to a solid oxide fuel cell stack, specifically including an air electrode current collector and a fuel electrode current collector. The air electrode current collector is disposed at the top of a single electrolyzer; the fuel electrode current collector is disposed at the bottom of the single electrolyzer. The fuel electrode current collector includes an inlet current collector, a central current collector, and an outlet current collector connected in sequence. Along the thickness direction of the fuel electrode current collector, the inlet current collector includes two mutually compressed first foamed metal layers, the central current collector includes two mutually compressed second foamed metal layers, and the outlet current collector includes two mutually compressed third foamed metal layers. The porosity of the inlet current collector is greater than that of the central current collector, and the porosity of the central current collector is greater than that of the outlet current collector. This foamed metal current collector assembly can improve the overall stability and efficiency of the electrolyzer.

Description

Technical Field

[0001] This invention relates to the field of solid oxide electrolysis technology, specifically to a foamed metal current collector assembly and a solid oxide fuel cell stack. Background Technology

[0002] Solid oxide electrolyzers (SOECs) can convert electrical energy into chemical energy under high-temperature conditions, offering advantages such as high efficiency, high current density, and environmental friendliness. They have broad application prospects in fields such as hydrogen production and CO2 resource utilization. The current collector, as a key component in the electrolyzer stack, undertakes multiple functions including electron conduction, gas transport, pressure distribution, and structural support. Its structure and performance directly determine the overall efficiency and service life of the electrolyzer.

[0003] In existing technologies, designs for nickel foam as current collectors are mostly concentrated in the field of proton exchange membrane fuel cells (PEMFCs), with relatively little research and application in solid oxide batteries (SOCs), especially solid oxide electrolyzers (SOECs). Structural control of nickel foam in PEMFCs primarily aims to improve water management and facilitate drainage: for example, CN109193005B uses nickel foam with different hydrophilicities to optimize drainage. These performance controls for nickel foam all revolve around the mass transfer and drainage requirements of PEMFCs, which differ significantly from the objectives of water vapor mass transfer, pressure distribution, and diffusion gradient matching required on the SOEC fuel electrode side. Another area involves foamed metal materials, but they are not used as current collectors; instead, they are used as electrode substrates with both high-temperature catalysis and structural support functions: for example, CN120443227A uses self-supporting foamed metal electrodes for water electrolysis; CN105762396B uses foamed metal electrodes in regenerative ammonia batteries, etc. None of the above solutions address the high-temperature stability, conductivity, gas distribution, and interface compatibility of foamed metal as a fuel electrode current collector or air electrode current collector under SOEC conditions, thus failing to meet the high performance and stability requirements of SOEC current collectors.

[0004] Therefore, current solid oxide fuel cell stacks suffer from technical problems such as poor stability and low efficiency. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose a foamed metal current collector assembly and a solid oxide fuel cell stack to solve the technical problems of poor stability and low efficiency in the prior art.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a foamed metal current collector assembly applied to a solid oxide fuel cell stack, specifically including an air electrode current collector and a fuel electrode current collector. The air electrode current collector is disposed at the top of a single electrolytic cell; the fuel electrode current collector is disposed at the bottom of the single electrolytic cell. The fuel electrode current collector includes an inlet current collector, a central current collector, and an outlet current collector connected in sequence. Along the thickness direction of the fuel electrode current collector, the inlet current collector includes two mutually compressed first foamed metal layers, the central current collector includes two mutually compressed second foamed metal layers, and the outlet current collector includes two mutually compressed third foamed metal layers. The porosity of the inlet current collector is greater than that of the central current collector, and the porosity of the central current collector is greater than that of the outlet current collector.

[0007] In some embodiments, the inlet manifold includes a first interlocking overlap layer formed by two layers of first foam metal extrusion, the center manifold includes a second interlocking overlap layer formed by two layers of second foam metal extrusion, and the outlet manifold includes a third interlocking overlap layer formed by two layers of third foam metal extrusion.

[0008] In some embodiments, the porosity φ1 of the inlet manifold plate satisfies φ1≥88%, and the areal density ρ1 of the inlet manifold plate satisfies 450g / m³. 2 ≤ρ1≤550g / m 2 The number of pores per unit length of the inlet manifold is between 85 PPI and 90 PPI.

[0009] In some embodiments, the porosity φ2 of the central manifold plate satisfies 82%≤φ2≤86%, and the areal density ρ2 of the central manifold plate satisfies 550g / m³. 2 ≤ρ2≤650g / m 2 The number of pores per unit length of the central manifold is between 95 PPI and 100 PPI.

[0010] In some embodiments, the porosity φ3 of the outlet manifold meets the requirement of 75%≤φ3≤80%, and the areal density ρ3 of the outlet manifold meets the requirement of 650g / m³. 2 ≤ρ3≤750g / m 2 The number of pores per unit length of the outlet manifold is between 105 PPI and 110 PPI.

[0011] In some embodiments, the base material of the inlet manifold, the center manifold, and the outlet manifold includes one or more of nickel, nickel-based alloys, iron-chromium alloys, or nickel-iron alloys.

[0012] In some embodiments, along the thickness direction of the air electrode current collector, the air electrode current collector includes a fourth foam metal layer and a fifth foam metal layer that are pressed against each other.

[0013] In some embodiments, the fourth foam metal layer and the fifth foam metal layer are made of the same material, and the areal density ρ4 of the fourth foam metal layer and the fifth foam metal layer satisfies 400g / m³. 2 ≤ρ4≤500g / m 2 The number of pores per unit length of the air electrode current collector is between 45 PPI and 60 PPI.

[0014] In some embodiments, the base material of the air electrode current collector includes one or more of cobalt-nickel alloy and ferritic stainless steel.

[0015] Secondly, the present invention also provides a solid oxide fuel cell stack, including the aforementioned foam metal current collector assembly.

[0016] Compared with existing technologies, the foamed metal current collector assembly provided by this invention divides the fuel electrode current collector into three functional areas: an inlet current collector, a central current collector, and an outlet current collector. Each area employs a double-layer extruded foamed metal structure with different porosities, achieving precise adaptation to different operating conditions within the fuel cell stack: the inlet current collector area uses a high-porosity structure to enhance gas flow capacity, expand the flow-pressure regulation window, reduce the risk of pressure surges, alleviate thermal stress, and improve sealing reliability. The central current collector area uses a medium-porosity structure to increase the conductive network density while ensuring gas transmission, thereby improving bulk conductivity and surface current collection capacity, and adapting to stable operation at high current densities. The outlet current collector uses an even lower porosity structure to increase local pressure and gas concentration gradient, ensuring sufficient water vapor supply and preventing reactant depletion and electrode degradation. This comprehensively improves the stability and electrolysis efficiency of the solid oxide fuel cell stack. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the fuel electrode current collector in the foam metal current collector assembly provided in this embodiment of the invention; Figure 2 yes Figure 1 Enlarged view of part A in the middle; Figure 3 yes Figure 1 Enlarged view of part B in the middle section; Figure 4 yes Figure 1 Enlarged view of part C in the middle; Figure 5 This is a schematic diagram of the structure of a solid oxide fuel cell stack according to the present invention; Figure 6 This is a schematic diagram showing the effect of fuel electrode current collector surface density and PPI on SOEC electrolysis performance and pressure. Figure 7This is a schematic diagram illustrating the impact of introducing a laminated structure into the fuel electrode current collector on the electrolysis performance and pressure of SOEC.

[0018] Explanation of reference numerals in the attached figures: 1. Solid oxide fuel cell stack; 10. Foam metal current collector assembly; 20. Upper support plate; 30. Metal connector; 40. Electrode seal; 50. Single electrolyzer; 60. Air flow chamber; 70. Fuel flow chamber; 80. Lower support plate.

[0019] 100. Fuel electrode current collector; 110. Inlet manifold; 111. First foam metal layer; 112. First interlocking overlapping layer; 120. Central manifold; 121. Second foam metal layer; 122. Second interlocking overlapping layer; 130. Outlet manifold; 131. Third foam metal layer; 132. Third interlocking overlapping layer; 200. Air electrode current collector. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0021] Solid oxide electrolyzers (SOECs) can convert electrical energy into chemical energy under high-temperature conditions, and their structure and performance directly determine the overall efficiency and lifespan of the electrolyzer. Currently, solid oxide fuel cell stacks suffer from technical problems such as poor stability and low efficiency.

[0022] To address technical issues such as poor stability and low efficiency, this invention provides a foamed metal current collector assembly, which can improve the overall stability and efficiency of the electrolytic cell.

[0023] It should be noted that the foamed metal manifold assembly of the present invention is applicable to, but not limited to, solid oxide electrolyzers, solid oxide fuel cells, water electrolysis devices, and related devices. For ease of explanation, the present invention will only describe the application of the foamed metal manifold assembly in a solid oxide electrolyzer as an example; the working principle of the foamed metal manifold assembly in other similar high-temperature electrochemical devices is essentially the same as that in solid oxide electrolyzers, and will not be elaborated further here.

[0024] This application provides a foamed metal manifold assembly 10, such as... Figures 1 to 4As shown, the foamed metal current collector assembly 10 is applied to a solid oxide fuel cell stack 1. The foamed metal current collector assembly 10 includes an air electrode current collector 200 and a fuel electrode current collector 100. The air electrode current collector 200 is disposed at the top of a single electrolytic cell 50; the fuel electrode current collector 100 is disposed at the bottom of the single electrolytic cell 50. The fuel electrode current collector 100 includes an inlet current collector 110, a central current collector 120, and an outlet current collector 130 connected in sequence. Along the thickness direction of the fuel electrode current collector 100, the inlet current collector 110 includes two mutually compressed first foamed metal layers 111, the central current collector 120 includes two mutually compressed second foamed metal layers 121, and the outlet current collector 130 includes two mutually compressed third foamed metal layers 131. The porosity of the inlet current collector 110 is greater than that of the central current collector 120, and the porosity of the central current collector 120 is greater than that of the outlet current collector 130.

[0025] The foamed metal manifold assembly 10 is a manifold used for airflow distribution and current collection in SOEC. Its structural feature is that it is made of foamed metal that can be zoned and controlled according to the differences in temperature field and current field under SOEC operating conditions. Specifically, it is divided into an air electrode manifold 200 and a fuel electrode manifold 100.

[0026] The air electrode current collector 200 serves to collect and conduct electrons, uniformly distribute gas, support and compress the electrode, and optimize mass and heat transfer. Collecting and conducting electrons efficiently removes electrons generated by the air electrode reaction, forming a complete electrical circuit and ensuring normal battery operation. Uniformly distributing gas evenly distributes air or oxygen onto the air electrode surface, ensuring stable reaction and facilitating the removal of generated oxygen. Supporting and compressing the electrode provides structural support, ensuring good contact and uniform pressure between the electrode, electrolyte, and metal connectors. Optimizing mass and heat transfer utilizes a porous structure to improve gas diffusion and heat distribution, enhancing the battery's high-temperature operating stability and electrolytic efficiency. In SOEC, the air electrode current collector 200 needs to perform additional functions of temperature distribution and pressure regulation, and operates in a highly oxidizing atmosphere for extended periods. Therefore, the design focus of the air electrode current collector 200 is on the selection and design of porosity and materials. The air electrode current collector 200 undergoes compression treatment to increase the density of the metal network in a certain thickness area on its surface, thereby increasing the current collection area and preventing excessive expansion of surface pores that could lead to breakage. The porosity and material of the air electrode current collector 200 will be explained later through specific embodiments and will not be elaborated upon here.

[0027] The fuel electrode current collector 100 serves multiple functions, including electron transport, gas distribution and exhaust, support and contact. Electron transport efficiently introduces electrons from the external circuit into the fuel electrode, providing an electron pathway for the electrolysis reaction. Gas distribution and exhaust uniformly delivers water vapor to the fuel electrode reaction interface and promptly removes the hydrogen generated in the reaction. Support and contact provide support to the fuel electrode, ensuring reliable contact and uniform pressure between it and the electrolyte and metal connector. Mass transfer and diffusion optimization establishes a stable water vapor diffusion gradient, optimizes mass transfer resistance, and improves electrolysis performance and operational stability.

[0028] It should be noted that the performance of the fuel electrode current collector 100 in a solid oxide electrolyzer (SOEC) is strongly correlated with its specific location in the stack, and the operating conditions of different regions vary significantly. Therefore, the fuel electrode current collector 100 includes an inlet current collector 110, a center current collector 120, and an outlet current collector 130 connected in sequence.

[0029] The inlet manifold 110 is the inlet area of ​​the electrolytic cell, such as... Figure 1 and Figure 2 As shown, the manifold in this area faces a complex environment of high pressure, high humidity, and large temperature difference. The core challenge lies in the coordinated control of pressure and temperature. On the one hand, the inlet pressure needs to be precisely controlled to ensure that the seals always operate within the safe pressure threshold, preventing seal failure due to overpressure. On the other hand, the temperature gradient caused by rapid heat exchange needs to be mitigated to avoid cracks or ruptures on the surface of the electrolytic cell due to excessive thermal stress.

[0030] The central manifold 120 is the central area of ​​the electrolytic cell, such as... Figure 1 and Figure 3 As shown, the current collector in this region operates primarily at high current density. The key is to achieve a balance between reactant supply and electrochemical performance. The current collector needs to operate stably at high current density while ensuring uniform distribution and efficient transport of water vapor, and maintaining suitable internal pressure to guarantee the continuous and efficient progress of the electrolysis reaction.

[0031] The outlet manifold 130 is the outlet area of ​​the electrolytic cell, such as... Figure 1 and Figure 4 As shown, the manifold in this region operates under conditions of rapid pressure drop and intense electrolytic reaction. The main challenge is preventing localized reactant depletion. Due to the rapid loss of gas pressure, insufficient water vapor supply is highly likely. Therefore, the manifold design must optimize the flow channel structure to ensure a sufficient supply of water vapor in the outlet area, avoiding excessively high local current density or electrode performance degradation due to reactant shortage.

[0032] Along the thickness direction of the fuel electrode current collector 100, the inlet current collector 110 includes two mutually compressed first foam metal layers 111, the center current collector 120 includes two mutually compressed second foam metal layers 121, and the outlet current collector 130 includes two mutually compressed third foam metal layers 131. The porosity of the inlet current collector 110 is greater than that of the center current collector 120, and the porosity of the center current collector 120 is greater than that of the outlet current collector 130. The material of the foam metal layers and the specific values ​​of the porosity of the inlet current collector 110, center current collector 120, and outlet current collector 130 can be determined according to actual needs, as long as the required size is met. Specific embodiments will be used to illustrate this later.

[0033] In this embodiment, the fuel electrode current collector 100 is divided into three functional areas: an inlet current collector 110, a central current collector 120, and an outlet current collector 130. Each area employs a double-layer extruded foam metal layer structure with different porosities to achieve precise adaptation to different operating conditions within the fuel cell stack. The inlet current collector 110 area uses a high-porosity structure to enhance gas flow capacity, expand the flow-pressure regulation window, reduce the risk of pressure surges, alleviate thermal stress, and improve sealing reliability. The central current collector 120 area uses a medium-porosity structure to increase the conductive network density while ensuring gas transmission, thereby improving bulk conductivity and surface current collection capacity, and adapting to stable operation at high current densities. The outlet current collector 130 uses an even lower porosity structure to increase local pressure and gas concentration gradients, ensuring sufficient water vapor supply and preventing reactant depletion and electrode degradation. This comprehensively improves the stability and electrolysis efficiency of the solid oxide fuel cell stack.

[0034] In some embodiments, such as Figures 1 to 4 As shown, the inlet manifold 110 includes a first interlocking overlapping layer 112 formed by two layers of first foam metal 111, the center manifold 120 includes a second interlocking overlapping layer 122 formed by two layers of second foam metal 121, and the outlet manifold 130 includes a third interlocking overlapping layer 132 formed by two layers of third foam metal 131.

[0035] In this embodiment, the inlet manifold 110, the center manifold 120, and the outlet manifold 130 are all formed by compressing two pieces of nickel foam with the same parameters. The compressed manifolds are then spliced ​​together and subjected to a second compression to ensure overall flatness. The first foam metal layer 111 is formed by two layers stacked and compressed; during compression, the middle foam metal forms an interlocking overlapping layer, known as the first interlocking overlapping layer 112. Similarly, the second foam metal layer 121 is formed by two layers stacked and compressed to create a second interlocking overlapping layer 122; and the third foam metal layer 131 is formed by two layers stacked and compressed to create a third interlocking overlapping layer 132. By employing this interlocking overlapping layer structure, the bonding force between the two foam metal layers is enhanced, preventing delamination and displacement, improving the overall structural strength and flatness of the manifold, reducing contact resistance, enhancing gas uniformity distribution, and improving the collection and mass transfer effects. In some embodiments, such as Figure 2 As shown, the porosity φ1 of the inlet manifold 110 satisfies φ1≥88%, and the areal density ρ1 of the inlet manifold 110 satisfies 450g / m³. 2 ≤ρ1≤550g / m 2 The number of pores per unit length of the inlet manifold 110 is between 85 PPI and 90 PPI.

[0036] In this embodiment, the porosity φ1 of the inlet manifold 110 can specifically be 88%, 89%, 90%, 91%, 92%, 93%, 95%, or any value between two adjacent values ​​mentioned above. The areal density ρ1 of the inlet manifold 110 can specifically be 450 g / m³. 2 470g / m 2 480g / m 2 500g / m 2 510g / m 2 520g / m 2 550g / m 2 Or, it can be any value between two adjacent values ​​mentioned above. The number of pores per unit length of the inlet manifold 110 is, for example, 85 PPI, 88 PPI, 90 PPI, etc. By limiting the porosity φ1, areal density ρ1, and number of pores per unit length of the inlet manifold 110, the gas flow in the inlet area is ensured, local pressure impact is reduced, gas distribution uniformity is improved, and the risk of sealing failure and battery cracking caused by large temperature difference, high humidity, and high pressure at the inlet is effectively mitigated.

[0037] In some embodiments, such as Figure 3 As shown, the porosity φ2 of the central manifold 120 satisfies 82%≤φ2≤86%, and the areal density ρ2 of the central manifold 120 satisfies 550g / m³. 2 ≤ρ2≤650g / m 2The number of pores per unit length of the central manifold 120 is between 95 PPI and 100 PPI.

[0038] In this embodiment, the porosity φ2 of the central manifold 120 can specifically be 82%, 83%, 84%, 85%, 86%, or any value between two adjacent values ​​mentioned above. The areal density ρ2 of the central manifold 120 can specifically be 550 g / m³. 2 570g / m 2 580g / m 2 600g / m 2 610g / m 2 620g / m 2 650g / m 2 Or, it can be any value between two adjacent values ​​mentioned above. The number of pores per unit length of the central manifold 120 is, for example, 95 PPI, 98 PPI, 100 PPI, etc. By limiting the porosity φ2, areal density ρ2, and number of pores per unit length of the central manifold 120, a balance between air permeability and structural density is ensured, the metal network density is increased, stability under high current density is enhanced, uniform water vapor transport is strengthened, and efficient and stable reaction in the central region is guaranteed.

[0039] In some embodiments, such as Figure 4 As shown, the porosity φ3 of the outlet manifold 130 satisfies 75%≤φ3≤80%, and the areal density ρ3 of the outlet manifold 130 satisfies 650g / m³. 2 ≤ρ2≤750g / m 2 The number of pores per unit length of the outlet manifold 130 is between 95 PPI and 100 PPI.

[0040] In this embodiment, the porosity φ3 of the outlet manifold 130 can specifically be 75%, 76%, 77%, 78%, 80%, or any value between two adjacent values ​​mentioned above. The areal density ρ3 of the outlet manifold 130 can specifically be 650 g / m³. 2 670g / m 2 680g / m 2 700g / m 2 710g / m 2 720g / m 2 750g / m 2Or, it can be any value between two adjacent values ​​mentioned above. The number of pores per unit length of the outlet manifold 130 is, for example, 105 PPI, 108 PPI, 110 PPI, etc. By limiting the porosity φ3, areal density ρ3, and number of pores per unit length of the outlet manifold 130, the density of the outlet area is increased, the local pressure is increased, the conductivity and structural strength are further improved, the uniformity of gas diffusion is ensured, the reactant concentration gradient in the outlet area is increased, water vapor deficit is avoided, and electrode performance decay is suppressed.

[0041] In some embodiments, the base material of the inlet manifold 110, the center manifold 120, and the outlet manifold 130 includes one or more of nickel, nickel-based alloys, iron-chromium alloys, or nickel-iron alloys.

[0042] In this embodiment, the material of the fuel electrode current collector 100 can be determined according to actual needs, such as nickel, nickel-based alloys, iron-chromium alloys, or nickel-iron alloys, etc.

[0043] In some embodiments, along the thickness direction of the air electrode current collector 200, the air electrode current collector includes a fourth foam metal layer and a fifth foam metal layer that are pressed against each other.

[0044] In this embodiment, the air electrode current collector 200 is the same as the fuel electrode current collector 100, both of which are formed by compressing two layers of foam metal. The air electrode current collector 200 is compressed to increase the density of the metal network in a certain thickness area on its surface, thereby increasing the current collection area and preventing the surface pores from expanding excessively and breaking.

[0045] It should be noted that the fourth and fifth foam metal layers can be made of the same material or of similar material properties. For example, the base material of the air electrode current collector 200 includes one or more of cobalt-nickel alloy and ferritic stainless steel. Co-Ni alloys include, for example, L-605, and ferritic stainless steels include, for example, SUS430 and SUS441.

[0046] In some embodiments, the fourth foam metal layer and the fifth foam metal layer are made of the same material, and the areal density ρ4 of the fourth foam metal layer and the fifth foam metal layer satisfies 400g / m³. 2 ≤ρ4≤500g / m 2 The number of pores per unit length of the air electrode current collector is between 45 PPI and 60 PPI.

[0047] In this embodiment, the fourth foam metal layer and the fifth foam metal layer are made of the same material, and the areal density ρ4 of the fourth foam metal layer can specifically be 400 g / m³. 2 420g / m 2 430g / m 2 450g / m2 460g / m 2 480g / m 2 500g / m 2 Or, it can be any value between two adjacent values ​​mentioned above. The number of pores per unit length of the air electrode current collector 200 is, for example, 45 PPI, 50 PPI, 60 PPI, etc. By using a design with two layers of the same material, consistent thermal expansion is ensured, reducing thermal stress. By limiting the areal density ρ4 and the number of pores per unit length of the air electrode current collector 200, both air permeability and conductivity are considered, adapting to the oxygen transport requirements on the air side and reducing mass transfer resistance.

[0048] Secondly, the present invention also provides a solid oxide fuel cell stack 1, such as... Figures 5 to 7 As shown, the solid oxide fuel cell stack 1 includes the aforementioned foam metal current collector assembly 10.

[0049] In this embodiment, the solid oxide fuel cell stack 1 sequentially includes an upper support plate 20, a foamed metal current collector assembly 10, a metal connector 30, an electrode seal 40, a single electrolytic cell 50, an air flow chamber 60, a fuel flow chamber 70, and a lower support plate 80.

[0050] In this embodiment, through parameter control and key stacking compression operations, layered regions of varying thicknesses are formed within the foamed metal plate. These regions enhance both the network density of the foamed metal surface and the diffusion rate of water vapor into the SOEC. In the inlet region, the manifold has a large flow-pressure regulation window, effectively balancing pressure distribution and reducing the risk of seal failure. In the central region, the thickness and areal density of the manifold's layered regions are increased within a controllable pressure range. The bulk conductivity and surface current collection capacity of the manifold are significantly improved during the formation of the layered structure. By compressing the water vapor flow channels, the mass flux at the water vapor-electrolysis cell interface is increased, which is beneficial for the stable operation of the SOEC at high current densities. In the outlet region, the thickness of the layered regions is further increased, effectively reducing the pressure difference in the outlet region and ensuring a sufficient concentration gradient for water vapor as it passes through this region, providing ample reactants to the SOEC.

[0051] In this embodiment, the solid oxide fuel cell stack using the above-mentioned foam metal current collector assembly 10 has higher structural stability, pressure adaptability, gas distribution uniformity and electrolysis efficiency, and the overall reliability and lifespan are significantly improved.

[0052] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A foamed metal current collector assembly, used in a solid oxide fuel cell stack, characterized in that, include: An air electrode current collector is installed at the top of a single electrolytic cell; A fuel electrode current collector is disposed at the bottom of a single electrolysis cell. The fuel electrode current collector includes an inlet current collector, a central current collector, and an outlet current collector connected in sequence. Wherein, along the thickness direction of the fuel electrode current collector, the inlet current collector includes two mutually compressed first foam metal layers, the center current collector includes two mutually compressed second foam metal layers, and the outlet current collector includes two mutually compressed third foam metal layers. The porosity of the inlet current collector is greater than that of the center current collector, and the porosity of the center current collector is greater than that of the outlet current collector.

2. The foamed metal manifold assembly according to claim 1, characterized in that, The inlet manifold includes a first interlocking overlapping layer formed by two layers of first foam metal extrusion, the center manifold includes a second interlocking overlapping layer formed by two layers of second foam metal extrusion, and the outlet manifold includes a third interlocking overlapping layer formed by two layers of third foam metal extrusion.

3. The foamed metal manifold assembly according to claim 2, characterized in that, The porosity φ1 of the inlet manifold plate satisfies φ1≥88%, and the areal density ρ1 of the inlet manifold plate satisfies 450g / m³. 2 ≤ρ1≤550g / m 2 The number of pores per unit length of the inlet manifold is between 85 PPI and 90 PPI.

4. The foamed metal manifold assembly according to claim 2, characterized in that, The porosity φ2 of the central manifold plate satisfies 82%≤φ2≤86%, and the areal density ρ2 of the central manifold plate satisfies 550g / m³. 2 ≤ρ2≤650g / m 2 The number of pores per unit length of the central manifold is between 95 PPI and 100 PPI.

5. The foamed metal manifold assembly according to claim 2, characterized in that, The porosity φ3 of the outlet manifold plate satisfies 75%≤φ3≤80%, and the areal density ρ3 of the outlet manifold plate satisfies 650g / m³. 2 ≤ρ3≤750g / m 2 The number of pores per unit length of the outlet manifold is between 105 PPI and 110 PPI.

6. The foamed metal manifold assembly according to claim 1, characterized in that, The base material of the inlet manifold, the center manifold, and the outlet manifold respectively includes one or more of nickel, nickel-based alloys, iron-chromium alloys, or nickel-iron alloys.

7. The foamed metal manifold assembly according to claim 1, characterized in that, Along the thickness direction of the air electrode current collector, the air electrode current collector includes a fourth foam metal layer and a fifth foam metal layer that are pressed against each other.

8. The foamed metal manifold assembly according to claim 7, characterized in that, The fourth foam metal layer and the fifth foam metal layer are made of the same material, and the areal density ρ4 of the fourth foam metal layer and the fifth foam metal layer both satisfy 400 g / m³. 2 ≤ρ4≤500g / m 2 The number of pores per unit length of the air electrode current collector is between 45 PPI and 60 PPI.

9. The foamed metal manifold assembly according to claim 7, characterized in that, The base material of the air electrode current collector includes one or more of cobalt-nickel alloy and ferritic stainless steel.

10. A solid oxide fuel cell stack, characterized in that, Includes the foamed metal manifold assembly as described in any one of claims 1-9.

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