A bipolar plate, proton conductor electrolytic cell stack and applications

Abstract

The application discloses a bipolar plate, a proton conductor electrolytic cell stack and application, and belongs to the solid oxide electrolytic cell field. The bipolar plate is provided with an anode surface and a cathode surface. N anode filling grooves are arranged on the anode surface, and anode gas flow channels are arranged in the anode filling grooves. N cathode filling grooves are arranged on the cathode surface, cathode gas flow channels are arranged in the cathode filling grooves, the anode filling grooves correspond to the cathode filling grooves in position, wherein N is greater than or equal to 2. A cathode gas inlet channel is arranged between at least two cathode filling grooves, and the cathode gas inlet channel is communicated with a cathode gas source. The electrolytic cell stack structure is particularly suitable for a proton conduction type membrane electrode assembly electrolytic cell stack with an unsuitable scale, and the electrolytic cell stack structure is simple and compact, so that a small-size membrane electrode assembly can realize a large-power electrolytic cell stack.

Description

A bipolar plate, a proton conductor electrolytic cell stack and its application Technical Field

[0001] This invention relates to the field of solid oxide electrolytic cells, specifically to a bipolar plate, a proton conductor electrolytic cell stack, and their applications. Background Technology

[0002] Proton-conducting solid oxide electrolyzers can use renewable energy sources such as wind and solar power to electrolyze water vapor to produce "green hydrogen." Compared to traditional oxygen-ion-conducting solid oxide electrolyzers, the hydrogen produced by water electrolysis in proton-conducting solid oxide electrolyzers is formed at the fuel electrode, eliminating the need for subsequent separation operations.

[0003] The practical application of proton-conducting solid oxide electrolyzers hinges on overcoming the challenge of large-scale development. Currently, the poor sintering activity and instability of typical Ba(Ce,Zr)O3-based electrolytes limit the large-scale development of proton-conducting electrolyzers. Large-size proton-conducting membrane electrodes are difficult to fabricate. For small-size membrane electrodes, achieving higher power levels within the same volume of the stack, and ensuring uniform distribution of the flow and temperature fields within the stack, are crucial for advancing the practical application of proton-conducting solid oxide electrolyzers. Therefore, there is an urgent need in this field to develop structural designs suitable for proton-conducting solid oxide electrolyzer stacks. Summary of the Invention

[0004] To overcome the problem that small-sized membrane electrodes are difficult to assemble into high-power stacks, this invention provides a bipolar plate, a proton conductor electrolytic cell stack and its application, which is suitable for assembling small-sized proton conduction membrane electrodes into a stack, and the stack height is reduced, which makes good use of the distribution of anode and cathode gases inside the stack.

[0005] This invention provides a bipolar plate having an anode surface and a cathode surface. N anode filling slots are provided on the anode surface, and an anode gas flow channel is provided within each anode filling slot. N cathode filling slots are provided on the cathode surface, and a cathode gas flow channel is provided within each cathode filling slot. The anode filling slots and cathode filling slots correspond to each other in position, wherein N ≥ 2. A cathode gas inlet channel is provided between at least two cathode filling slots, and the cathode gas inlet channel is connected to a cathode gas source.

[0006] Furthermore, the bipolar plate is selected from SUS430 material, ZML232L material or Crofer22APU material.

[0007] The present invention also provides a proton conductor electrolytic cell stack, which sequentially includes an upper fixed plate, an upper insulating plate, an upper current collector plate, multiple battery repeating units, a lower current collector plate, a lower insulating plate and a lower fixed plate;

[0008] The battery repeating unit sequentially includes an anode current collector grid, a membrane electrode, a cathode current collector grid, and the aforementioned bipolar plate. The anode current collector grid is disposed in the anode filling groove of the bipolar plate, the cathode current collector grid is disposed in the cathode filling groove of the bipolar plate, and the membrane electrode is located between the anode current collector grid and the cathode current collector grid of two adjacent bipolar plates.

[0009] Furthermore, the effective area S of each of the membrane electrodes is ≤ 25 cm². 2 .

[0010] Furthermore, sealing gaskets are provided between the membrane electrode and the bipolar plate, between the upper current collector and the plurality of battery repeating units, and between the plurality of battery repeating units and the lower current collector.

[0011] Furthermore, an insulating pad is provided between adjacent bipolar plates to prevent the bodies of adjacent bipolar plates from contacting each other.

[0012] The present invention also provides an application of the above-mentioned proton conductor electrolyzer stack in the electrolysis of water vapor, electrolysis of carbon dioxide, power generation by electrolysis of water vapor and carbon dioxide, electrolysis of hydrocarbon fuels or solid oxide fuel cells.

[0013] The beneficial effects of this invention are as follows:

[0014] The large-scale development of existing proton-conducting membrane electrodes is limited by their small size. Furthermore, traditional fuel cell stack designs often result in poor gas distribution uniformity within the proton-conducting stack. This invention proposes a novel proton-conducting fuel cell stack structure suitable for assembling small-sized proton-conducting membrane electrodes. The stack height is reduced, and the distribution of anode and cathode gases within the stack is optimized. The resulting compact stack structure exhibits high power density at temperatures ranging from 300 to 600°C. This stack structure is particularly suitable for electrolyzing steam, carbon dioxide, and other hydrocarbon fuels. It can also be used for power generation applications using hydrogen, methane, and other hydrocarbon fuels. Attached Figure Description

[0015] Figure 1 is a schematic diagram of the structure of a proton conductor electrolytic cell stack in one embodiment of the present invention.

[0016] In the diagram, 1 is the upper fixing plate; 2 is the upper insulating plate; 3 is the upper current collector plate; 4 is the anode current collector grid; 5 is the membrane electrode; 6 is the cathode current collector grid; 7 is the bipolar plate; 8 is the lower current collector plate; 9 is the lower insulating plate; 10 is the lower fixing plate; 11 is the sealing gasket; 12 is the insulating gasket; and 13 is the cathode gas inlet channel. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0018] Referring to Figure 1, a bipolar plate 7 is provided with an anode surface and a cathode surface. N anode filling slots are provided on the anode surface, and an anode gas flow channel is provided in the anode filling slot. N cathode filling slots are provided on the cathode surface, and a cathode gas flow channel is provided in the cathode filling slot. The anode filling slots and the cathode filling slots are corresponding in position, wherein N≥2. A cathode gas inlet channel 13 is provided between at least two cathode filling slots, and the cathode gas inlet channel 13 is connected to a cathode gas source.

[0019] Furthermore, the bipolar plate 7 is selected from SUS430 material, ZML232L material or Crofer22APU material.

[0020] A proton conductor electrolytic cell stack includes, in sequence, an upper fixed plate 1, an upper insulating plate 2, an upper current collector plate 3, multiple battery repeating units, a lower current collector plate 8, a lower insulating plate 9, and a lower fixed plate 10;

[0021] The battery repetitive unit includes an anode current collector 4, a membrane electrode 5, a cathode current collector 6, and the aforementioned bipolar plate 7. The anode current collector 4 is disposed in the anode filling groove of the bipolar plate 7, the cathode current collector 6 is disposed in the cathode filling groove of the bipolar plate 7, and the membrane electrode 5 is located between the anode current collector 4 and the cathode current collector 6 of two adjacent bipolar plates 7.

[0022] Furthermore, the effective area S of each of the membrane electrodes is ≤ 25 cm². 2 .

[0023] Furthermore, sealing gaskets 11 are provided between the membrane electrode 5 and the bipolar plate 7, between the upper current collector 3 and the plurality of battery repeating units, and between the plurality of battery repeating units and the lower current collector 8.

[0024] Furthermore, an insulating pad 12 is provided between adjacent bipolar plates 7.

[0025] Application of a proton conductor electrolyzer stack in the electrolysis of steam, electrolysis of carbon dioxide, power generation by electrolysis of steam and carbon dioxide, electrolysis of hydrocarbon fuels or solid oxide fuel cells.

[0026] The following are specific examples.

[0027] Example 1

[0028] The membrane electrode 5 is a 5cm*5cm proton conduction type membrane electrode, and there are 100 membrane electrodes 5 in total. The bipolar plate 7 is made of 430 stainless steel with a thickness of 2.5mm. Each side of the bipolar plate 7 contains four anode filling slots and four cathode filling slots, each with an external dimension of 5.5cm*5.5cm. The sealing gasket 11 is a glass-ceramic sealing gasket with a thickness of 1mm. The cathode current collector 6 is made of nickel foam, and the anode current collector 4 is a protective 430 mesh. The upper fixing plate 1 and the lower fixing plate 10 are both made of Crofer22APU material with a thickness of 10mm.

[0029] The electrolytic cell stack of Example 1 was tested in steam electrolysis mode: at 500℃ and 1.3V, the electrolysis current density was -33A, and the hydrogen production rate reached 0.15m. 3 / h.

Claims

1. An application of a proton conductor electrolyzer stack in solid oxide fuel cell power generation, characterized in that, The proton conductor electrolytic cell stack sequentially includes an upper fixed plate (1), an upper insulating plate (2), an upper current collector plate (3), multiple battery repeating units, a lower current collector plate (8), a lower insulating plate (9), and a lower fixed plate (10); the battery repeating unit includes an anode current collector grid (4), a membrane electrode (5), a cathode current collector grid (6), and a bipolar plate (7). The anode current collector grid (4) is disposed in the anode filling groove of the bipolar plate (7), the cathode current collector grid (6) is disposed in the cathode filling groove of the bipolar plate (7), and the membrane electrode (5) is located in the anode current collector grid of two adjacent bipolar plates (7). 4) Between the cathode current collector (6); the bipolar plate (7) is provided with an anode surface and a cathode surface, N anode filling slots are provided on the anode surface, and an anode gas flow channel is provided in the anode filling slot; N cathode filling slots are provided on the cathode surface, and a cathode gas flow channel is provided in the cathode filling slot, the anode filling slot and the cathode filling slot are corresponding in position, wherein N≥2; a cathode gas inlet channel (13) is provided between at least two cathode filling slots, and the cathode gas inlet channel (13) is connected to the cathode gas source; the effective area S of each membrane electrode is ≤25cm 2 A sealing gasket (11) is provided between the membrane electrode (5) and the bipolar plate (7), between the upper current collector (3) and the plurality of battery repeating units, and between the plurality of battery repeating units and the lower current collector (8).

2. The application of the proton conductor electrolyzer stack according to claim 1 in solid oxide fuel cell power generation, characterized in that, The bipolar plate (7) is selected from SUS430 material, ZML232L material or Crofer22APU material.

3. The application of the proton conductor electrolyzer stack according to claim 1 in solid oxide fuel cell power generation, characterized in that, An insulating pad (12) is provided between adjacent bipolar plates (7).

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