A cross-flow tube and box solid oxide fuel cell stack

Abstract

The application discloses a cross-flow tube box type solid oxide fuel cell stack, which comprises a box body, a plurality of vertically-installed and matrix-arranged tube type solid oxide fuel cell units are arranged in the box body, the tube type solid oxide fuel cell unit comprises, from inside to outside, a porous anode support tube, an anode reaction layer, an electrolyte layer and a cathode reaction layer; the central cavity of the porous anode support tube forms an anode gas passage along the vertical direction, and the top of the anode gas passage is communicated with a fuel groove at the top of the box body; the cathode reaction layer and the box body form a cathode gas passage along the horizontal direction, and the left side wall and the right side wall of the box body are respectively provided with a cathode gas inlet and a cathode gas outlet. The anode and the cathode of the cell stack adopt the cross-flow mode to pass in fuel and air, which is favorable for increasing the reaction contact time and the reaction rate, thereby improving the power generation efficiency.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and more specifically to a cross-flow tube box-type solid oxide fuel cell stack. Background Technology

[0002] Solid oxide fuel cells (SOFCs) are a type of third-generation fuel cell. They are devices that can directly convert chemical energy into electrical energy. They mainly consist of four components connected in series: cathode, anode, electrolyte, and connector, forming a stack with a rated power output.

[0003] SOFCs offer several advantages: high power density, resulting in greater energy output for the same volume / weight; noiseless operation, as SOFCs operate solely through chemical reactions with no mechanical movement, and their primary emission is water, achieving zero pollution; modularity, allowing multiple individual cells to be connected in series or parallel to form battery packs to adapt to various application scenarios; availability and variety of fuels, including hydrogen, hydrocarbons, and methanol, without the need for precious metal catalysts; and an all-solid-state structure, eliminating the risk of pollutant leakage. These advantages make them promising for applications in the energy supply sector. Currently, SOFCs are mainly available in flat-plate, tubular, conical, corrugated, and honeycomb structures. Among these, tubular SOFCs offer good sealing and are widely used. However, traditional tubular structures typically employ unidirectional flow channels, preventing the airflow from fully covering the SOFC's cathode reaction layer. This results in a low volume of gas participating in the reaction, leading to low fuel utilization and consequently low power generation efficiency, thus hindering the development of SOFCs. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a cross-flow tube box-type solid oxide fuel cell stack, in which fuel and air are introduced into the anode and cathode in a cross-flow manner, which is beneficial for increasing the reaction contact time, increasing the reaction rate, and thus improving power generation efficiency.

[0005] The technical solution adopted in this invention is as follows:

[0006] A cross-flow tube box-type solid oxide fuel cell stack includes a box housing, in which a plurality of vertically installed tubular solid oxide fuel cell units are disposed. Each tubular solid oxide fuel cell unit includes, from the inside out, a porous anode support tube, an anode reaction layer, an electrolyte layer and a cathode reaction layer.

[0007] The central cavity of the porous anode support tube forms a vertical anode gas channel, and the top of the anode gas channel is connected to the fuel tank at the top of the tank.

[0008] A transverse cathode gas channel is formed between the cathode reaction layer and the housing, and the left and right walls of the housing are respectively provided with cathode gas inlets and cathode gas outlets.

[0009] Furthermore, the housing is provided with 1 to 5 layers of partitions, each partition having a number of holes. The tubular solid oxide fuel cell unit is inserted into the holes of the partitions, and a gap is provided between the tubular solid oxide fuel cell unit and the holes of the partitions.

[0010] Furthermore, several layers of cathode gas channels are formed between the cathode reaction layer and the box and partition, and each layer of cathode gas channel is provided with a cathode gas inlet and a cathode gas outlet at both ends.

[0011] Furthermore, the cathode gas inlet is a tapered tube that gradually expands towards the inside of the chamber, and the cathode gas outlet is a tapered tube that gradually narrows towards the outside of the chamber.

[0012] Furthermore, the tubular solid oxide fuel cell unit is provided with an exhaust port at its bottom.

[0013] Furthermore, the enclosure includes a top plate, a middle shell, and a bottom plate. The top plate and the bottom plate are respectively fixedly disposed on the top and bottom of the middle shell, and the top plate and the bottom plate are sealed to the middle shell. The top plate, the middle shell, and the bottom plate of the enclosure are made of heat-insulating material or covered with heat-insulating material.

[0014] The height of the middle shell is 1 / 2 of the power output of the solid oxide fuel cell stack;

[0015] The width of the middle shell is equal to the height of the middle shell;

[0016] The length of the middle shell is twice the width of the middle shell;

[0017] The thickness of the middle shell is 25-50 mm, and the thickness of the top plate and bottom plate is 25-50 mm.

[0018] Furthermore, the thickness of the partition is 15–30 mm.

[0019] Furthermore, the porous anode support tube is made of a breathable and heat-resistant material, the length of the porous anode support tube is equal to the height of the middle shell, the inner diameter of the porous anode support tube is 20-80mm, and the wall thickness is 2-5mm.

[0020] In the above technical solution, the inner diameter of the porous anode support tube is determined according to the rated power of the fuel cell stack. Specifically, for kilowatt-level fuel cell stacks, the inner diameter of the porous anode support tube is 20-30 mm; for hundred-kilowatt-level fuel cell stacks, the inner diameter of the porous anode support tube is 30-60 mm; and for megawatt-level fuel cell stacks, the inner diameter of the porous anode support tube is 60-80 mm.

[0021] Furthermore, several tubular solid oxide fuel cell units are arranged in a matrix to form a tubular solid oxide fuel cell unit matrix, and the tubular solid oxide fuel cell unit matrix is ​​located in the middle of the casing; the ratio of the longitudinal length to the transverse width of the tubular solid oxide fuel cell unit matrix is ​​1 to 1.5:1, the ratio of the longitudinal length to the cathode gas channel length is 1.5 to 2:3, and the ratio of the transverse width to the cathode gas channel width is 3 to 4:5. The beneficial effects of this invention are:

[0022] (1) The cross-flow tube box-type solid oxide fuel cell stack provided by the present invention has an anode gas channel perpendicular to a cathode gas channel, which allows fuel and air to be introduced into the anode and cathode in a cross-flow manner, which is beneficial to increase the reaction contact time of the anode and cathode, increase the reaction rate, and thus improve the power generation efficiency.

[0023] (2) The cross-flow tube box-type solid oxide fuel cell stack provided by the present invention has a cathode gas channel with an inlet that is a tapered tube that gradually expands toward the inside of the box and an outlet that is a tapered tube that gradually narrows toward the outside of the box. The cathode gas is a transverse diffusion flow, which utilizes the gas entering from the cathode gas inlet to gradually preheat before the reaction, avoids thermal shock, prevents the formation of excessive temperature difference from affecting the temperature uniformity and life of the battery, and also avoids internal short circuits in the battery, thus improving the reliability of the battery.

[0024] (3) The cross-flow tube box-type solid oxide fuel cell stack provided by the present invention is connected between the cathode gas channels of each layer through the gap between the tube solid oxide fuel cell unit and the hole of the partition, so that the cathode gas can flow between the cathode gas channels of each layer through the gap, which makes good use of the gas distribution balance and temperature balance between the cathode gas channels of each layer. Attached Figure Description

[0025] To clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of the cross-flow tube box-type solid oxide fuel cell stack of the present invention;

[0027] Figure 2 This is a schematic diagram of the internal structure of the cross-flow tube box-type solid oxide fuel cell stack of the present invention;

[0028] Figure 3 This is a cross-sectional view of the cross-flow tube box-type solid oxide fuel cell stack of the present invention;

[0029] Figure 4 This is a cross-sectional view of a tubular solid oxide fuel cell unit.

[0030] The diagram is labeled as follows: 1. Housing; 101. Top plate; 102. Middle shell; 103. Bottom plate; 2. Separator; 3. Tubular solid oxide fuel cell unit; 301. Porous anode support tube; 302. Anode reaction layer; 303. Electrolyte layer; 304. Cathode reaction layer; 4. Anode gas channel; 5. Fuel tank; 6. Cathode gas channel; 601. Cathode gas inlet; 602. Cathode gas outlet; 7. Drainage base; 701. Exhaust port. Detailed Implementation

[0031] This invention provides a cross-flow tube box-type solid oxide fuel cell stack. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0032] The present invention will now be described in detail with reference to the accompanying drawings.

[0033] Reference Figure 1-4 This embodiment provides a cross-flow tube box-type solid oxide fuel cell stack, including a housing 1. The housing 1 includes a top plate 101, a middle shell 102, and a bottom plate 103. The top plate 101, the middle shell 102, and the bottom plate 103 are made of or covered with heat-insulating material. The top plate 101 and the bottom plate 103 are respectively fixedly disposed on the top and bottom of the middle shell 102, and the top plate 101, the bottom plate 103, and the middle shell 102 are sealed together.

[0034] In the aforementioned housing 1, the height of the middle shell is determined based on the rated power generation P of the solid oxide fuel cell stack. The height of the middle shell 102 is 1 / 2 of the rated power generation of the solid oxide fuel cell stack. The unit of the middle shell height is mm, and the unit of the rated power generation P is W.

[0035] Specifically, in this embodiment, the rated power of the fuel cell stack is 1kW, so the height of the middle shell is 500mm; the width of the middle shell is equal to the height of the middle shell, which is 500mm; the length of the middle shell is twice the width of the middle shell, which is 1000mm; the thickness of the middle shell is 25mm, and the thickness of the top plate and the bottom plate is 25mm.

[0036] The aforementioned settings for the height, length, and width of the inner shell meet the airflow requirements of the fuel cell stack at its highest power output. If the dimensions are too large, the fuel consumption rate will increase, thereby reducing power generation efficiency; if the dimensions are too small, the fuel utilization rate will be excessively reduced, thus affecting the stack power output.

[0037] The aforementioned box 1 is provided with two layers of partitions 2, and each layer of partition 2 is provided with holes arranged in a 4*4 array; wherein, the thickness of the partition is 15mm, and the distance between two adjacent partitions is 15cm.

[0038] The aforementioned housing 1 also houses several vertically mounted tubular solid oxide fuel cell units 3 arranged in a matrix, forming a tubular solid oxide fuel cell unit matrix. The number of holes in the matrix is ​​equal to that in the partition plate, and they are arranged in a 4*4 array within the housing 1. The tubular solid oxide fuel cell unit array is located at the center of the housing, with a longitudinal length of 500 mm and a transverse width of 400 mm to ensure the flow and preheating of the cathode gas. In addition, the height of each tubular solid oxide fuel cell unit 3 is equal to the height of the middle shell 102, and its two ends are fixed between the top and bottom plates of the housing. The tubular solid oxide fuel cell unit 3 is inserted into the holes of the partition plate 2, which serves to fix it. Furthermore, the connection between the tubular solid oxide fuel cell unit 3 and the holes of the partition plate 2 is non-sealed, with a gap between them.

[0039] The aforementioned tubular solid oxide fuel cell unit 3 specifically includes, from the inside out, a porous anode support tube 301, an anode reaction layer 302, an electrolyte layer 303, and a cathode reaction layer 304. The aforementioned anode reaction layer 302, electrolyte layer 303, and cathode reaction layer 304 are fixed to the outer wall of the porous anode support tube 301 by coating printing. Furthermore, the inner walls of the porous anode support tubes 301 at both ends of the aforementioned tubular solid oxide fuel cell unit 3 are fully sealed to the outer walls of the cathode reaction layer 302.

[0040] The porous anode support tube 301 has a smooth wall surface with several holes, is made of a breathable and heat-resistant material, and has an inner diameter of 20mm and a wall thickness of 2mm. The central cavity of the porous anode support tube 301 forms a vertical anode gas channel 4, the top of which is connected to the fuel tank 5 at the top of the housing 1. The fuel tank 5 has threads on its outer side for connection to a fuel delivery pipe. Three horizontal cathode gas channels 6 are formed between the cathode reaction layer 304, the housing 1, and the partition 2. The length and width of channel 6 are equal to the length and width of the middle shell, and each layer of cathode gas channel 6 is provided with a cathode gas inlet 601 and a cathode gas outlet 602 at both ends. The cathode gas inlet 601 and cathode gas outlet 602 are located on the left and right sides of the box 1, respectively. The cathode gas inlet 601 is a tapered tube that gradually expands towards the inside of the box 1, and the cathode gas outlet 602 is a tapered tube that gradually narrows towards the outside of the box 1. The inner diameter of the constricted end of the cathode gas inlet 601 and cathode gas outlet 602 is 150mm.

[0041] In addition, the bottom of the tubular solid oxide fuel cell unit 3 is provided with a drainage base 7, and a vent 701 is provided on one side of the drainage base 7. The vent 701 can be connected to the pipeline to exhaust the high-temperature water vapor generated during the reaction process.

[0042] Example 2

[0043] Reference Figure 1-4 This embodiment provides a cross-flow tube box-type solid oxide fuel cell stack, including a housing 1. The housing 1 includes a top plate 101, a middle shell 102, and a bottom plate 103. The top plate 101, the middle shell 102, and the bottom plate 103 are made of or covered with heat-insulating material. The top plate 101 and the bottom plate 103 are respectively fixedly disposed on the top and bottom of the middle shell 102, and the top plate 101, the bottom plate 103, and the middle shell 102 are sealed together.

[0044] In the aforementioned housing 1, the height of the middle shell is determined based on the rated power P of the solid oxide fuel cell stack. The height of the middle shell 102 is half of the rated power of the solid oxide fuel cell stack. The unit of the middle shell height is mm, and the unit of the rated power P is kW. Specifically, in this embodiment, the rated power of the fuel cell stack is 10kW, so the height of the middle shell is 5000mm. The width of the middle shell is equal to the height of the middle shell, which is 5000mm. The length of the middle shell is twice the width of the middle shell, which is 10000mm. The thickness of the middle shell is 50mm, and the thickness of the top plate and the bottom plate is 50mm.

[0045] The aforementioned settings for the height, length, and width of the inner shell meet the airflow requirements of the fuel cell stack at its highest power output. If the dimensions are too large, the fuel consumption rate will increase, thereby reducing power generation efficiency; if the dimensions are too small, the fuel utilization rate will be excessively reduced, thus affecting the stack power output.

[0046] The aforementioned box 1 is provided with 5 layers of equally spaced partitions 2, and each partition 2 is provided with holes arranged in a 40*40 array; wherein, the thickness of the aforementioned partitions is 30mm.

[0047] The aforementioned housing 1 also contains several vertically mounted tubular solid oxide fuel cell units 3 arranged in a matrix, forming a tubular solid oxide fuel cell unit matrix. The number of holes in the matrix is ​​equal to that in the partition plate. The matrix is ​​arranged in a 40*40 array within the housing 1, with the tubular solid oxide fuel cell unit array located at the center of the housing. Its longitudinal length is 5000mm and its transverse width is 4000mm. Furthermore, the height of each tubular solid oxide fuel cell unit 3 is equal to the height of the middle shell 102. Its two ends are fixed between the top and bottom plates of the housing. The tubular solid oxide fuel cell unit 3 is inserted into the holes in the partition plate 2, which serves to fix it. In addition, the connection between the tubular solid oxide fuel cell unit 3 and the holes in the partition plate 2 is non-sealed, with a gap between them.

[0048] The aforementioned tubular solid oxide fuel cell unit 3 specifically includes, from the inside out, a porous anode support tube 301, an anode reaction layer 302, an electrolyte layer 303, and a cathode reaction layer 304. The aforementioned anode reaction layer 302, electrolyte layer 303, and cathode reaction layer 304 are fixed to the outer wall of the porous anode support tube 301 by coating printing. Furthermore, the inner walls of the porous anode support tubes 301 at both ends of the aforementioned tubular solid oxide fuel cell unit 3 are fully sealed to the outer walls of the cathode reaction layer 302.

[0049] The porous anode support tube 301 has a smooth wall surface with several holes, is made of a breathable and heat-resistant material, and has an inner diameter of 30mm and a wall thickness of 5mm. The central cavity of the porous anode support tube 301 forms a vertical anode gas channel 4, the top of which is connected to the fuel tank 5 at the top of the housing 1. The fuel tank 5 has threads on its outer side for connection to a fuel delivery pipe. Three horizontal cathode gas channels 6 are formed between the cathode reaction layer 304, the housing 1, and the partition 2. The length and width of channel 6 are equal to the length and width of the middle shell, and each layer of cathode gas channel 6 is provided with a cathode gas inlet 601 and a cathode gas outlet 602 at both ends. The cathode gas inlet 601 and cathode gas outlet 602 are located on the left and right sides of the box 1, respectively. The cathode gas inlet 601 is a tapered tube that gradually expands towards the inside of the box 1, and the cathode gas outlet 602 is a tapered tube that gradually narrows towards the outside of the box 1. The inner diameter of the constricted end of the cathode gas inlet 601 and cathode gas outlet 602 is 150mm.

[0050] In addition, the bottom of the tubular solid oxide fuel cell unit 3 is provided with a drainage base 7, and a vent 701 is provided on one side of the drainage base 7. The vent 701 can be connected to the pipeline to exhaust the high-temperature water vapor generated during the reaction process.

[0051] It should be noted that any parts not mentioned in this invention can be achieved by using or referencing existing technologies.

[0052] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A cross-flow tube box-type solid oxide fuel cell stack, characterized in that, The device includes a housing, which contains several vertically mounted tubular solid oxide fuel cell units. Each tubular solid oxide fuel cell unit includes, from the inside out, a porous anode support tube, an anode reaction layer, an electrolyte layer, and a cathode reaction layer. The central cavity of the porous anode support tube forms a vertical anode gas channel, and the top of the anode gas channel is connected to the fuel tank at the top of the tank. A transverse cathode gas channel is formed between the cathode reaction layer and the housing, and the left and right walls of the housing are respectively provided with cathode gas inlets and cathode gas outlets. The enclosure includes a top plate, a middle shell, and a bottom plate. The top plate and bottom plate are fixedly installed on the top and bottom of the middle shell, respectively, and the top plate and bottom plate are sealed to the middle shell. The top plate, middle shell, and bottom plate of the enclosure are made of or covered with heat-insulating materials. The height of the middle shell is 1 / 2 of the rated power of the solid oxide fuel cell stack. The unit of the middle shell height is mm, and the unit of the rated power of the solid oxide fuel cell stack is W. The width of the middle shell is equal to the height of the middle shell; The length of the middle shell is twice the width of the middle shell; The thickness of the middle shell is 25~50mm, and the thickness of the top plate and bottom plate is 25~50mm; The height, length, and width of the middle shell are set to meet the airflow requirements of the fuel cell stack at its highest power generation. The tubular solid oxide fuel cell unit is provided with a drainage base at the bottom, and an exhaust port is provided on one side of the drainage base. The exhaust port can be connected to the pipeline to exhaust the high-temperature water vapor generated during the reaction process.

2. The cross-flow tube box-type solid oxide fuel cell stack according to claim 1, characterized in that, The housing is provided with 1 to 5 layers of partitions, each partition having several holes. The tubular solid oxide fuel cell unit is inserted into the holes of the partition, and a gap is provided between the tubular solid oxide fuel cell unit and the holes of the partition.

3. A cross-flow tube box-type solid oxide fuel cell stack according to claim 2, characterized in that, The cathode reaction layer forms several layers of cathode gas channels with the box and partition, and each layer of cathode gas channel is provided with a cathode gas inlet and a cathode gas outlet at both ends.

4. A cross-flow tube box-type solid oxide fuel cell stack according to claim 3, characterized in that, The cathode gas inlet is a tapered tube that gradually expands towards the inside of the chamber, and the cathode gas outlet is a tapered tube that gradually narrows towards the outside of the chamber.

5. A cross-flow tube box-type solid oxide fuel cell stack according to claim 2, characterized in that, The thickness of the partition is 15~30mm.

6. A cross-flow tube box-type solid oxide fuel cell stack according to claim 1, characterized in that, The porous anode support tube is made of breathable and heat-resistant material. The length of the porous anode support tube is equal to the height of the middle shell. The inner diameter of the porous anode support tube is 20~80mm and the wall thickness is 2~5mm.

7. A cross-flow tube box-type solid oxide fuel cell stack according to claim 1, characterized in that, Several tubular solid oxide fuel cell units are arranged in a matrix to form a tubular solid oxide fuel cell unit matrix, and the tubular solid oxide fuel cell unit matrix is ​​located in the middle of the box. The ratio of the longitudinal length to the transverse width of the tubular solid oxide fuel cell unit matrix is ​​1~1.5:1, the ratio of the longitudinal length to the cathode gas channel length is 1.5~2:3, and the ratio of the transverse width to the cathode gas channel width is 3~4:5.

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