Electrolytic cell for monitoring internal state in situ based on optical fiber

Abstract

The invention relates to the technical field of hydrogen energy safety monitoring, in particular to an electrolytic bath for monitoring the internal state in situ based on optical fibers. Comprising a cathode end plate and an anode end plate, the anode end plate is located on one side of the cathode end plate, the side wall of the cathode end plate is fixedly connected with a cathode gasket, the end, away from the cathode end plate, of the cathode gasket is fixedly connected with a cathode plate, and the side wall of the cathode plate is fixedly connected with a cathode liner; a main groove and an auxiliary groove are formed in the cathode plate and the anode plate respectively, and a main optical fiber and an auxiliary optical fiber of a temperature type FBG sensor and a strain type FBG sensor are embedded, so that the temperature type FBG sensor and the strain type FBG sensor are integrated, and the temperature type FBG sensor and the strain type FBG sensor are integrated. Monitoring points are directly arranged in a reaction core area and are close to a membrane electrode and a flow field, and key information such as temperature gradient and mechanical stress change in the flow field direction can be captured in real time.

Description

Technical Field

[0001] This invention relates to the field of hydrogen energy safety monitoring technology, and more specifically, to an electrolyzer based on in-situ optical fiber monitoring of its internal state. Background Technology

[0002] Electrolysis of water is an ideal way to produce green hydrogen. Electrolysis of water is a technology that uses electricity to decompose water (H2O) and convert it into hydrogen (H2) and oxygen (O2). The essence of electrolysis of water is that an oxidation-reduction reaction occurs in the electrolyzer, and electrical energy is converted into chemical energy and stored in hydrogen. The electrolysis system mainly consists of four parts: electrolyzer, electrodes, electrolyte, and power supply.

[0003] Therefore, it can be seen that during long-term operation, the mechanical stress caused by electrolyte circulation and thermal expansion may lead to structural fatigue and leakage. Therefore, monitoring is required during operation. Fiber optic sensing technology is a commonly used monitoring method. However, conventional fiber optic-based electrolytic cells often need to be placed outside the flow field area, or even outside the cell. This makes the monitoring data susceptible to severe environmental interference, resulting in data distortion and making it difficult to accurately grasp the physical state of the reaction area. Summary of the Invention

[0004] This invention provides an electrolytic cell for in-situ monitoring of the internal state using optical fibers. By creating main and secondary trenches on the cathode and anode plates respectively, and embedding main and secondary optical fibers that integrate temperature-type and strain-type FBG sensors, the monitoring points are directly arranged in the core reaction region close to the membrane electrode and flow field. This allows for real-time capture of key information such as temperature gradient and mechanical stress changes along the flow field direction, thereby solving the problems mentioned in the background art. Specifically, conventional optical fiber-based electrolytic cells often need to avoid the flow field region or even be placed outside the cell, which makes the monitoring data susceptible to severe environmental interference, resulting in data distortion and difficulty in accurately grasping the physical state of the reaction region.

[0005] To achieve the above objectives, an electrolytic cell based on in-situ fiber optic monitoring of internal conditions includes a cathode end plate and an anode end plate. The anode end plate is located on one side of the cathode end plate. A cathode pad is fixedly connected to the side wall of the cathode end plate. A cathode plate is fixedly connected to the end of the cathode pad away from the cathode end plate. A cathode liner is fixedly connected to the side wall of the cathode plate. An anode liner is fixedly connected to the end of the cathode liner away from the cathode plate. A membrane electrode is fixedly connected to the inner surfaces of the anode liner and the cathode liner. An anode plate is fixedly connected to the end of the anode liner away from the cathode liner. An anode pad is fixedly connected to the side wall of the anode plate. The side wall of the anode pad is fixedly connected to the side wall of the anode end plate.

[0006] In the above technical solution, the sidewall of the cathode plate is provided with a main groove, and the inner surface of the main groove of the cathode plate is inserted with a main optical fiber. The sidewall of the anode plate is provided with a secondary groove, and the inner surface of the secondary groove of the anode plate is inserted with a secondary optical fiber. The end of the cathode plate away from the main groove is provided with a main flow channel, and the end of the anode plate away from the secondary groove is provided with a secondary flow channel.

[0007] Based on the above, the width of the main trench and the secondary trench is 1 to 2 mm, and the depth is 2 to 3 mm. The inner surfaces of the main optical fiber and the secondary optical fiber are equipped with temperature-type FBG sensors and strain-type FBG sensors. The inner surfaces of the main optical fiber and the secondary optical fiber are equipped with polyimide coating and PTFE protective sleeve. The PTFE protective sleeve is used to protect the main optical fiber and the secondary optical fiber. The outer surfaces of the main optical fiber and the secondary optical fiber are equipped with acid and alkali resistant silicone. The acid and alkali resistant silicone is used to seal and fill the main optical fiber and the secondary optical fiber.

[0008] Compared with the prior art, the beneficial effects of the present invention are as follows: In this in-situ fiber optic monitoring electrolytic cell, main and secondary trenches are opened on the cathode and anode plates respectively, and main and secondary optical fibers are embedded in the main and secondary trenches to achieve real-time online monitoring of multi-physical field information such as temperature and stress in the reaction area of ​​the electrolytic cell. Several FBG sensors arranged on the surface of the main and secondary optical fibers are used to reflect the temperature gradient and mechanical load changes in the flow field direction. The surface of the main and secondary optical fibers is covered with a polyimide coating and a PTFE protective sleeve to prevent electrolyte penetration and oxidation corrosion, thereby ensuring the long-term stability of the monitoring device. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 In this invention Figure 1 A schematic diagram of the structure at point A; Figure 3 This is a side view of the cathode plate in this invention. Figure 4 In this invention Figure 3 A schematic diagram of the structure at point B; Figure 5 This is a side view of the anode plate in this invention. Figure 6 In this invention Figure 5 A schematic diagram of the structure at point C.

[0010] The meanings of the labels in the diagram are as follows: 1. Cathode end plate; 2. Cathode gasket; 3. Cathode plate; 4. Cathode liner; 5. Membrane electrode; 6. Anode liner; 7. Anode plate; 8. Anode gasket; 9. Anode end plate; 10. Main optical fiber; 11. Secondary optical fiber; 12. Main trench; 13. Secondary trench; 14. Main flow channel; 15. Secondary flow channel. Detailed Implementation

[0011] The technical solutions of this invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0012] Since conventional fiber-optic-based electrolyzers often need to be placed outside the flow field area, or even outside the cell, they are easily affected by environmental interference when monitoring data, resulting in data distortion and making it difficult to accurately grasp the physical state of the reaction area. This is not conducive to the intelligent control and safety early warning of the hydrogen production system.

[0013] Therefore, in view of the above-mentioned problems, the present invention provides an electrolytic cell based on in-situ monitoring of its internal state using optical fiber, with reference to... Figure 1-2 As shown, it includes a cathode end plate 1 and an anode end plate 9. The anode end plate 9 is located on one side of the cathode end plate 1. The cathode end plate 1 and the anode end plate 9 form an overall load-bearing frame. The anode end plate 9 is arranged on one side of the cathode end plate 1. The symmetrical electrode plate layout makes the electric field distribution uniform during the electrolysis process. A cathode gasket 2 is fixedly connected to the side wall of the cathode end plate 1. The cathode gasket 2 blocks the penetration path of the electrolyte into the cathode end plate 1 and reduces the corrosion of the cathode end plate 1. A cathode plate 3 is fixedly connected to the end of the cathode pad 2 away from the cathode end plate 1. The connection between the cathode plate 3 and the cathode pad 2 can increase the stability of the reaction process. A cathode liner 4 is fixedly connected to the side wall of the cathode plate 3. The connection between the cathode plate 3 and the cathode liner 4 can support the membrane electrode 5. An anode pad 6 is fixedly connected to the end of the cathode pad 4 away from the cathode plate 3. A membrane electrode 5 is fixedly connected to the inner surfaces of the anode pad 6 and the cathode pad 4. The cathode pad 4 and the anode pad 6 can apply uniform clamping pressure to the membrane electrode 5 to ensure that the membrane electrode 5 is in close contact with the two pads. An anode plate 7 is fixedly connected to the end of the anode pad 6 away from the cathode pad 4. The anode plate 7 and the cathode plate 3 form a current loop. An anode gasket 8 is fixedly connected to the side wall of the anode plate 7. The side wall of the anode gasket 8 is fixedly connected to the side wall of the anode plate 9. The tight connection between the anode gasket 8 and the anode plate 9 can strengthen the overall structure.

[0014] See again Figure 2 As shown, a main groove 12 is provided on the side wall of the cathode plate 3, and a main optical fiber 10 is inserted into the inner surface of the main groove 12 of the cathode plate 3. The main groove 12 is oriented on the side wall of the cathode plate 3 to provide an installation slot for the main optical fiber 10.

[0015] refer to Figure 3-4 As shown, a main channel 14 is provided at the end of the cathode plate 3 away from the main trench 12. The main channel 14 serves as the core channel for electrolyte transport and product discharge, allowing the electrolyte to be evenly distributed along the flow field direction.

[0016] refer to Figure 5-6 As shown, a secondary groove 13 is formed on the side wall of the anode plate 7, and a secondary optical fiber 11 is inserted into the inner surface of the secondary groove 13 of the anode plate 7. The secondary optical fiber 11 and the main optical fiber 10 form a symmetrical dual monitoring layout. At the same time, the secondary groove 13 provides an installation slot for the secondary optical fiber 11. The data collected by the secondary optical fiber 11 and the main optical fiber 10 are complementary. A secondary flow channel 15 is formed at the end of the anode plate 7 away from the secondary groove 13. The layout forms a symmetrical design of the anode and cathode, making the overall flow field distribution of the electrolytic cell more uniform.

[0017] See again Figure 2 , Figure 4 and Figure 6 As shown, the width of the main trench 12 and the secondary trench 13 is 1 to 2 mm and the depth is 2 to 3 mm. Their dimensions are adapted to the outer diameter of the main optical fiber 10 and the secondary optical fiber 11, thereby achieving a tight fit between the main optical fiber 10 and the secondary optical fiber 11. Both the main optical fiber 10 and the secondary optical fiber 11 are equipped with temperature-type FBG sensors and strain-type FBG sensors on their surfaces, enabling synchronous monitoring and real-time reflection of changes in thermal stress and mechanical strain. This overcomes the limitation of a single sensor monitoring only a single parameter. The inner surfaces of both the main optical fiber 10 and the secondary optical fiber 11 are coated with a polyimide layer and a PTFE protective sleeve. The PTFE protective sleeve is used to protect the main optical fiber 10 and the secondary optical fiber 11. The outer surfaces of both the main optical fiber 10 and the secondary optical fiber 11 are coated with acid and alkali-resistant silicone. The acid and alkali-resistant silicone is used to seal and fill the main optical fiber 10 and the secondary optical fiber 11. By setting protective mechanisms on the surfaces of the main optical fiber 10 and the secondary optical fiber 11, signal transmission is ensured, while also isolating the electrolyte.

[0018] The working principle of this invention is as follows: Before electrolysis, the anode end plate 9, cathode pad 2, cathode plate 3, cathode liner 4, membrane electrode 5, anode liner 6, anode plate 7, anode pad 8, and anode end plate 9 are assembled together in sequence. During assembly, the main optical fiber 10 and the secondary optical fiber 11 are inserted into the inner walls of the main trench 12 and the secondary trench 13, respectively. When electrolysis begins, the electrolyte enters the anode and cathode reaction areas through the main flow channel 14 of the cathode plate 3 and the secondary flow channel 15 of the anode plate 7, respectively. During the reaction, the thermal deformation of the cathode plate 3 and anode plate 7 caused by temperature changes is buffered by the elastic properties of the cathode gasket 2 and anode gasket 8. While the electrolysis reaction is in progress, the dual monitoring system composed of the main optical fiber 10 and the secondary optical fiber 11 simultaneously conducts in-situ monitoring. The non-invasive measurement main optical fiber 10 and secondary optical fiber 11 are embedded in the main trench 12 and the secondary trench 13, without affecting the flow field and electrochemical performance. The temperature-type FBG sensor and the strain-type FBG sensor set inside the main optical fiber 10 and the secondary optical fiber 11 will capture the temperature gradient changes and the mechanical stress fluctuations of the plates in the reaction area. The collected information is transmitted to other equipment through the main optical fiber 10 and the secondary optical fiber 11, thereby achieving in-situ monitoring of the stress and temperature field in the reaction area (flow field) of the electrolytic cell.

[0019] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An electrolytic cell based on in-situ optical fiber monitoring of internal state, comprising a cathode end plate (1) and an anode end plate (9), characterized in that: The anode plate (9) is located on one side of the cathode plate (1). A cathode pad (2) is fixedly connected to the side wall of the cathode plate (1). A cathode plate (3) is fixedly connected to the end of the cathode pad (2) away from the cathode plate (1). A cathode liner (4) is fixedly connected to the side wall of the cathode plate (3). An anode liner (6) is fixedly connected to the end of the cathode liner (4) away from the cathode plate (3). A membrane electrode (5) is fixedly connected to the inner surfaces of the anode liner (6) and the cathode liner (4). An anode plate (7) is fixedly connected to the end of the anode liner (6) away from the cathode liner (4). An anode pad (8) is fixedly connected to the side wall of the anode plate (7). The side wall of the anode pad (8) is fixedly connected to the side wall of the anode plate (9).

2. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 1, characterized in that: The cathode plate (3) has a main groove (12) on its side wall, and a main optical fiber (10) is inserted into the inner surface of the main groove (12) of the cathode plate (3).

3. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 2, characterized in that: The anode plate (7) has a secondary groove (13) on its side wall, and a secondary optical fiber (11) is inserted into the inner surface of the secondary groove (13) of the anode plate (7).

4. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 2, characterized in that: The cathode plate (3) has a main channel (14) at the end away from the main trench (12).

5. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 3, characterized in that: A secondary flow channel (15) is provided at the end of the anode plate (7) away from the secondary trench (13).

6. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 3, characterized in that: The width of the main groove (12) and the secondary groove (13) is 1 to 2 mm, and the depth is 2 to 3 mm.

7. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 3, characterized in that: The surfaces of the main optical fiber (10) and the secondary optical fiber (11) are each provided with a temperature-type FBG sensor and a strain-type FBG sensor.

8. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 3, characterized in that: The outer surfaces of the main optical fiber (10) and the secondary optical fiber (11) are sequentially covered with a polyimide coating and a PTFE protective sleeve. The PTFE protective sleeve is used to protect the main optical fiber (10) and the secondary optical fiber (11) from electrolyte corrosion.

9. The electrolytic cell for in-situ monitoring of internal state using optical fiber according to claim 3, characterized in that: The outer surfaces of the main optical fiber (10) and the secondary optical fiber (11) are provided with acid and alkali resistant silicone, which is used to seal and fill the main optical fiber (10) and the secondary optical fiber (11).

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