Flat plate type solid oxide fuel cell connector and electric pile framework

Abstract

The invention relates to a flat plate type solid oxide fuel cell connector and an electric pile framework, and the connector comprises a hydrogen flow channel layer, an isolation layer and an air flow channel layer, an anode hydrogen side runner and a cathode air side runner of the connecting body are thoroughly isolated by the single cell sealing mechanism through a cover plate, a first sealing layer, a second sealing layer and a third sealing layer; a cathode pressing plate, a cathode insulation pad, a cathode end plate, the third sealing layer, the first cover plate, the second sealing layer, a soft coating O2, a battery, the first sealing layer, a soft coating H2 and the connecting body are sequentially arranged from bottom to top; the invention relates to a galvanic pile structure which comprises a first sealing layer, a second cover plate, a third sealing layer, a second cover plate, a second sealing layer, a soft coating O2, a battery, a soft coating H2, an anode end plate, an anode insulating plate, an anode pressing plate, and fastening bolts for fastening the cathode pressing plate and the anode pressing plate at the upper end and the lower end, and has the advantages that cracking or sealing failure caused by high-temperature circulation and thermal expansion difference can be avoided; and leakage of hydrogen and air on two sides of the connector can be avoided, cross infection is prevented, and breakage caused by uneven stress of the battery can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of new energy and energy-saving technologies, and in particular to a planar solid oxide fuel cell connector and a fuel cell stack architecture. Background Art

[0002] Solid oxide fuel cells (SOFCs) are all-solid-state chemical power generation devices that efficiently and environmentally friendly convert the chemical energy stored in fuel and oxidant into electricity at medium to high temperatures. Operating temperatures typically hover around 800°C, the interconnects not only transmit electrons but also distribute gas flow and provide mechanical support. Therefore, the design of the interconnects must consider mechanical properties, fluid heat transfer characteristics, and electrochemical performance. Currently available interconnects often suffer from poor stack performance and short service life.

[0003] To solve the above problems, previously disclosed patents usually find it difficult to take into account the transient changes in temperature and pressure fields caused by gas-liquid-solid coupling and electrochemistry in the flow channel, the complexity and cost of connector production and processing, and the stack assembly process. Since the material properties and phase changes of the gases undergoing chemical reactions on both sides of the connector can easily cause uneven distribution of temperature and pressure fields on one side of the connector, and the uneven temperature and pressure on both sides of the connector can easily affect the solid oxide fuel cell. Due to the material properties of the solid oxide fuel cell itself, the temperature and pressure deviations are large, which can easily cause battery rupture. The complexity of the connector design makes it difficult to take into account both production costs and the overall design efficiency of the stack.

[0004] For example, in patent CN113328113A "A method for preparing a solid oxide fuel cell / electrolyzer connector", the design is that the gas enters the first groove 11 from the first air inlet 13 and then flows out through the first flow channel 17. However, this technical solution has no other flow-disturbing devices and isolation ribs except the isolation rib 19, resulting in extremely poor uniformity of fluid distribution between the flow channels. The uneven fluid distribution can easily lead to large temperature and pressure deviations and other deficiencies.

[0005] For example, in patent CN116314976A "An Indirect Internal Reforming Solid Oxide Fuel Cell Connector", the design of the indirect internal reforming solid oxide fuel cell connector also includes a gas distribution part 50 for connecting gas materials and corresponding flow channels. The gas distribution part 50 can be provided with multiple gas distribution strips to make the gas distribution more uniform. The cathode and anode side flow channels adopt a cross flow channel design, which can expand the length and width of the connector. The increased area is mainly in the fluid distribution area, but the reaction area area has not been increased, resulting in an increase in the overall volume and a decrease in the volume power density of the stack.

[0006] Another example is patent CN218351507U "A connector for solid oxide fuel cells", which designs the groove area on the plate body into a "convex"-shaped contour structure. In order to maintain the uniformity of the speed / flow of the gas entering the flow channel through the through hole, the structure of the flow channel area is also improved so that its overall contour is consistent with the outer contour of the groove area, which is conducive to the uniformity of gas distribution in the flow channel. Through the cooperation of the spoiler block structure, the uniformity of material distribution can be further improved. However, the spoiler structure of this technical solution causes irregularity in the reaction area, resulting in a decrease in the effective area ratio of the battery, a decrease in the volume power density of the entire stack design, and complex production and processing. At the same time, because it uses the cathode and anode side flow channels as the same flow channels, the gas reaction stoichiometric ratios on both sides are different during the actual reaction process, which easily leads to pressure deviations on both sides of the connector and does not conform to actual application conditions.

[0007] In summary, the background technology and the related patents retrieved by our research group have the following problems or deficiencies:

[0008] (1) Uneven fluid distribution leads to temperature and pressure deviations. Fluid distribution is a major consideration in connector design. Currently, the fluid distribution deviation of some connector designs may be as high as 10%. Fluid distribution deviations between different flow channels will lead to differences in reaction rate and reaction intensity. The complexity of solid-gas-heat-electric coupling causes uneven distribution of overall temperature and pressure. This temperature and pressure gradient can easily cause battery performance degradation and failure.

[0009] (2) The irregular reaction area leads to irregular battery shape or a small proportion of the battery's effective area. At present, some connector designs change the reaction area to an irregular shape to ensure uniform fluid distribution. The irregular shape will lead to an irregular battery shape or a reduction in the proportion of the battery's effective area. The irregular shape of the battery will lead to uneven bending force of the battery and increase the complexity of processing and assembly. The reduction in the proportion of the effective area will lead to a large overall battery stack design size and a reduction in volume power density.

[0010] (3) The cathode and anode side flow channels adopt the same flow channel design concept, which does not conform to the actual application situation. Since the pressure requirements on the cathode and anode sides remain the same, but the cathode and anode gas volume ratios are different, the inlet and outlet sizes of the cathode and anode sides are different during the actual design process. This results in the use of the same flow channel design concept not being in line with the actual application situation.

[0011] Therefore, it is particularly urgent and significant to seek a planar solid oxide fuel cell connector and stack architecture. Summary of the Invention

[0012] The task of the present invention is to overcome the deficiencies of the prior art and provide a planar solid oxide fuel cell connector and a stack architecture.

[0013] The present invention is mainly to solve the following problems:

[0014] (1) Uneven fluid distribution leads to temperature and pressure deviations. Fluid distribution is a major consideration in connector design. Currently, the fluid distribution deviation of some connector designs may be as high as 10%. Fluid distribution deviations between different flow channels will lead to differences in reaction rate and reaction intensity. The complexity of solid-gas-heat-electric coupling causes uneven distribution of overall temperature and pressure. Such temperature and pressure gradients can easily cause battery performance degradation and failure.

[0015] (2) The irregular reaction area leads to irregular battery shape or a small proportion of the battery's effective area. In order to ensure uniform fluid distribution, some current connector designs change the reaction area to an irregular shape. The irregular shape will lead to an irregular battery shape or a reduction in the proportion of the battery's effective area. The irregular shape of the battery will cause uneven bending force on the battery and increase the complexity of processing and assembly. The reduction in the proportion of the effective area will lead to a large overall stack design size and a reduction in volume power density.

[0016] The cathode and anode side flow channels adopt the same flow channel design concept because the pressure requirements on the cathode and anode sides are consistent, but the different cathode and anode gas volume ratios will cause the inlet and outlet sizes of the cathode and anode sides to be different during the actual design process, ultimately resulting in the use of the same flow channel design concept not being suitable for actual application conditions.

[0017] The task of the present invention is accomplished by the following technical solutions:

[0018] A flat-plate solid oxide fuel cell connector and stack architecture, the connector includes a hydrogen flow channel layer, an isolation layer and an air flow channel layer, a single-cell sealing mechanism that completely isolates the anode hydrogen side flow channel and the cathode air side flow channel of the connector through a cover plate and sealing layer 1, sealing layer 2, and sealing layer 3, and a stack architecture in which a cathode pressure plate, a cathode insulating pad, a cathode end plate, sealing layer 3, cover plate 1, sealing layer 2, soft coating O2, battery, sealing layer 1, soft coating H2, connector, sealing layer 3, cover plate 2, sealing layer 2, soft coating O2, battery, soft coating H2, anode end plate, anode insulating plate, and anode pressure plate are arranged in sequence from bottom to top, and the cathode pressure plates and anode pressure plates at the upper and lower ends are fastened with fastening bolts. This architecture can not only avoid cracking or sealing failure caused by high-temperature cycling and thermal expansion differences, but also avoid leakage of hydrogen and air gases on both sides of the connector, prevent cross infection, and avoid rupture due to uneven force on the battery.

[0019] Compared with the prior art, the present invention has the following advantages or beneficial effects:

[0020] (1) The fluids on both sides adopt a two-inlet and one-outlet design. Different flow channel forms on both sides of the connector are designed according to the properties of the anode and cathode fluids. The gas inlet and outlet areas, different gas distribution areas, and gas collection areas are designed according to the reaction requirements. The results show that the fluid distribution on both sides is well uniform; the maximum deviation of fluid distribution between the flow channels is less than 5%, and the maximum deviation of fluid distribution between the five cells is less than 1%.

[0021] (2) According to the production process of the battery stack, a connector with a regular reaction area is designed to increase the effective area of ​​the battery reaction, while ensuring uniform force during battery installation, reducing the complexity of connector processing, and achieving high efficiency and low cost.

[0022] (3) A cover plate is added for battery installation and auxiliary sealing. The cover plate plays a protective and supporting role for the battery during the installation of the battery stack, ensuring that the battery installation is evenly stressed. Double-sided sealing is performed on both sides of the cover plate to ensure that both the anode and cathode sides are sealed, effectively avoiding gas leakage.

[0023] The % mentioned in the application documents refers to mass percentage. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a comparison diagram of the fluid distribution uniformity between the flow channels of a flat-plate solid oxide fuel cell connector and a stack structure proposed by the present invention.

[0025] Figure 2 This is a comparison diagram of the fluid distribution uniformity between cells of a flat-plate solid oxide fuel cell connector and a stack architecture proposed by the present invention.

[0026] Figure 3 This is a schematic diagram of the anode side flow channel structure of a flat solid oxide fuel cell connector and stack architecture proposed by the present invention. Figure 1 .

[0027] Figure 4 This is a schematic diagram of the anode side flow channel structure of a flat solid oxide fuel cell connector and stack architecture proposed by the present invention. Figure 2 .

[0028] Figure 5 This is a schematic diagram of the cathode side flow channel structure of a flat solid oxide fuel cell connector and stack architecture proposed by the present invention. Figure 1 .

[0029] Figure 6 This is a schematic diagram of the cathode side flow channel structure of a flat solid oxide fuel cell connector and stack architecture proposed by the present invention. Figure 2 .

[0030] Figure 7It is a schematic diagram of the cross-sectional structure of a planar solid oxide fuel cell connector and a stack architecture connector proposed in the present invention.

[0031] Figure 8 It is a cross-sectional schematic diagram of a flat-plate solid oxide fuel cell connector and a single-cell sealing structure of a stack architecture proposed in the present invention.

[0032] Figure 9 This is a schematic diagram of the decomposition of a flat-plate solid oxide fuel cell connector and a stack architecture battery sealing structure proposed in the present invention.

[0033] Figure 10 This is a schematic diagram of the decomposition of a flat-plate solid oxide fuel cell connector and stack architecture and stack sealing structure proposed in the present invention.

[0034] The symbols in the accompanying drawings represent:

[0035] 1. Hydrogen Inlet 1 2. Gas Distribution Channel 3. Hydrogen-Side Mounting Sealing Surface 4. Gas Distribution Channel Ridge 5. Hydrogen Inlet 2 6. Gas Distribution Area 7. Reaction Area 8. Gas Collection Area 9. Channel Ridge 10. Channel 11. Gas Collection Channel 12. Hydrogen Outlet 13. Gas Collection Channel Ridge 14. Air Inlet 1 15. Gas Distribution Groove 16. Gas Distribution Auxiliary Bump 17. Air Inlet 2 18. Gas Collection Groove 19. Air-Side Mounting Sealing Surface 20. Air Outlet 21. Gas Collection Auxiliary Bump 22. Hydrogen Flow Channel Layer 23. Isolation Layer 24. Air Flow Channel Layer 25. Fastening Bolts 26. Anode Pressure Plate 27. Anode Insulation Gasket 28. Anode End Plate 29. Cell 30. Sealing Layer 2 31. Cover Plate 32. Sealing Layer 3 33. Connector 34. Cathode End Plate 35. Cathode Insulation Gasket 36. Cathode Pressure Plate 37. Soft H2 Coating 38. Soft O2 Coating 39. Sealing Layer 1

[0036] The present invention is described in further detail below with reference to the accompanying drawings. DETAILED DESCRIPTION

[0037] like Figures 1 to 10As shown, a flat solid oxide fuel cell connector and stack architecture, the connector (33) includes a hydrogen flow channel layer (22), an isolation layer (23) and an air flow channel layer (24), a single cell sealing mechanism that completely separates the anode hydrogen side flow channel and the cathode air side flow channel of the connector (33) through a cover plate (31) and a sealing layer 1 (39), a sealing layer 2 (30) and a sealing layer 3 (32), and a cathode pressure plate (37), a cathode insulating pad (36), a cathode end plate (35), a sealing layer 3 (32), a cover plate 1 (31), a sealing layer 2 (30), a soft coating O2 (39), a battery (29), a sealing layer 1 (40) are sequentially arranged from bottom to top. ), soft coating H2 (38), connector (33), sealing layer three (32), cover plate two (34), sealing layer two (30), soft coating O2 (39), battery (29), soft coating H2 (38), anode end plate (28), anode insulating plate (27), anode pressure plate (26), and fastening bolts (25) to fasten the cathode pressure plate (37) and the anode pressure plate (26) at the upper and lower ends to form a stack structure, which can avoid cracking or sealing failure caused by high temperature cycle and thermal expansion difference, and avoid leakage of hydrogen and air gas on both sides of the connector (33), prevent cross infection, and avoid rupture of the battery (19) due to uneven force.

[0038] The connector and stack architecture of the present invention may further include:

[0039] The hydrogen side flow channel of the connector (33) corresponds to the air side flow channel in a one-to-one manner, and the hydrogen side flow channel ridge corresponds to the air side flow channel ridge in a one-to-one manner.

[0040] The hydrogen side flow channel of the connector (33) allows hydrogen to enter from the hydrogen inlet 1 (1) and the hydrogen inlet 2 (5), pass through the hydrogen side gas distribution area (6) including the gas distribution flow channel (2) and the gas distribution flow channel ridge (4), and first undergo forced distribution in the gas distribution area (6), and then undergo uniform distribution in the mixed flow area before entering the reaction area, and then enter the hydrogen reaction area (7) for electrochemical reaction. The fluid flowing out of the reaction area is first uniformized in the mixed flow area of ​​the gas collection area (8) including the gas collection flow channel (11) and the gas collection flow channel ridge (13), and then partially forced to converge. The gas collection flow channel ridge (13) is opened to assist in uniform pressure, and then the converged gas flows out through the hydrogen outlet (12).

[0041] The air side flow channel of the connector (33) allows air to enter from the air inlet 1 (14) and the air inlet 2 (17), pass through the air gas distribution area (6) provided with a gas distribution groove (15) and a gas distribution auxiliary protrusion (16), and then enter the air reaction area (7) for electrochemical reaction after passing through the gas distribution auxiliary protrusion (16) turbulence group. The fluid flowing out of the air reaction area (7) passes through the gas collection auxiliary protrusion (21) turbulence group in the gas collection area and then flows out through the air outlet (20). The air side gas collection area (8) includes a gas collection groove (18) and a gas collection auxiliary protrusion (21).

[0042] The single cell sealing structure is provided with a sealing layer three (32), a cover plate (31), a sealing layer two (30), a soft coating O2 (38), a battery (29), a sealing layer one (39), a soft coating H2 (37), and a connector (33) from bottom to top. The sealing layer two (30) is used to bond and seal the connector's anode hydrogen side mounting sealing surface (3) and the cover plate (31); the battery (29) is sandwiched therein, and the soft coating H2 (37) is located between the hydrogen side flow channel ridge (9) and the battery (29); the sealing layer three (32) is used to bond and seal the connector's cathode air side mounting sealing surface (19) and the cover plate (31), and the soft coating O2 (39) is located between the air side flow channel ridge (9) and the battery (19), thereby optimizing the contact between the battery (29) and the connector 33, enhancing the durability, stability and safety of the battery (29), and improving the efficiency of the battery stack.

[0043] The battery stack sealing structure includes only two batteries (29), and the number of batteries (29) can be increased or decreased by cyclically stacking the single-cell sealing structure.

[0044] As described above, the present invention can be better implemented. The above embodiments are only the best implementation methods of the present invention, but the implementation methods of the present invention are not limited to the above embodiments. Other changes, modifications, replacements, combinations, and simplifications made without departing from the spirit and principles of the present invention should be considered equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. Flat-plate solid oxide fuel cell connector and stack architecture, characterized by The connector (33) includes a hydrogen flow channel layer (22), an isolation layer (23) and an air flow channel layer (24), a single cell sealing mechanism that completely separates the anode hydrogen side flow channel and the cathode air side flow channel of the connector (33) through a cover plate (31) and a sealing layer 1 (39), a sealing layer 2 (30) and a sealing layer 3 (32), and a cathode pressure plate (37), a cathode insulating pad (36), a cathode end plate (35), a sealing layer 3 (32), a cover plate 1 (31), a sealing layer 2 (30), a soft coating O2 (39), a battery (29), a sealing layer 1 (40), a soft coating H2 (38), The battery stack structure comprises a connector (33), a sealing layer three (32), a cover plate two (34), a sealing layer two (30), a soft coating O2 (39), a battery (29), a soft coating H2 (38), an anode end plate (28), an anode insulating plate (27), an anode pressure plate (26), and a fastening bolt (25) used to fasten the cathode pressure plate (37) and the anode pressure plate (26) at the upper and lower ends. This structure can avoid cracking or sealing failure caused by high-temperature cycles and thermal expansion differences, and can also avoid leakage of hydrogen and air gases on both sides of the connector (33), prevent cross infection, and avoid rupture of the battery (19) due to uneven stress.

2. The connector and stack structure according to claim 1 is characterized in that The hydrogen side flow channel of the connector (33) corresponds to the air side flow channel in a one-to-one manner, and the hydrogen side flow channel ridge corresponds to the air side flow channel ridge in a one-to-one manner.

3. The connector and stack structure according to claim 1 or 2, characterized in that The hydrogen side flow channel of the connector (33) allows hydrogen to enter from the hydrogen inlet 1 (1) and the hydrogen inlet 2 (5), pass through the hydrogen side gas distribution area (6) including the gas distribution flow channel (2) and the gas distribution flow channel ridge (4), and first undergo forced distribution in the gas distribution area (6), and then undergo uniform distribution in the mixed flow area before entering the reaction area, and then enter the hydrogen reaction area (7) for electrochemical reaction. The fluid flowing out of the reaction area is first uniformized in the mixed flow area of ​​the gas collection area (8) including the gas collection flow channel (11) and the gas collection flow channel ridge (13), and then partially forced to converge. The gas collection flow channel ridge (13) is opened to assist in uniform pressure, and then the converged gas flows out through the hydrogen outlet (12).

4. The connector and stack structure according to claim 1, characterized in that The air side flow channel of the connector (33) allows air to enter from the air inlet 1 (14) and the air inlet 2 (17), pass through the air gas distribution area (6) provided with a gas distribution groove (15) and a gas distribution auxiliary protrusion (16), and then enter the air reaction area (7) for electrochemical reaction after passing through the gas distribution auxiliary protrusion (16) turbulence group. The fluid flowing out of the air reaction area (7) passes through the gas collection auxiliary protrusion (21) turbulence group in the gas collection area and then flows out through the air outlet (20). The air side gas collection area (8) includes a gas collection groove (18) and a gas collection auxiliary protrusion (21).

5. The connector and stack structure according to claim 1 is characterized in that The single cell sealing structure is provided with a sealing layer three (32), a cover plate (31), a sealing layer two (30), a soft coating O2 (38), a battery (29), a sealing layer one (39), a soft coating H2 (37), and a connector (33) from bottom to top. The sealing layer two (30) is used to bond and seal the connector's anode hydrogen side mounting sealing surface (3) and the cover plate (31); the battery (29) is sandwiched therein, and the soft coating H2 (37) is located between the hydrogen side flow channel ridge (9) and the battery (29); the sealing layer three (32) is used to bond and seal the connector's cathode air side mounting sealing surface (19) and the cover plate (31), and the soft coating O2 (39) is located between the air side flow channel ridge (9) and the battery (19), thereby optimizing the contact between the battery (29) and the connector 33, enhancing the durability, stability and safety of the battery (29), and improving the efficiency of the battery stack.

6. The connector and stack structure according to claim 1, characterized in that The battery stack sealing structure includes only two batteries (29), and the number of batteries (29) can be increased or decreased by cyclically stacking the single-cell sealing structure.

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