An electrolytic cell auxiliary fastening device and fastening method

Abstract

The application provides an electrolytic cell auxiliary fastening device and a fastening method. The electrolytic cell auxiliary fastening device comprises: a peripheral support for providing support for the auxiliary fastening device; a force applying assembly arranged on the peripheral support and used for applying pressure to a central region of the electrolytic cell; the force applying assembly comprises at least one of a single-sided tray, a single-sided pressing block or a double-sided pressing block; and a driving assembly connected with the force applying assembly and used for driving the force applying assembly to move to adjust the pressure applied to the electrolytic cell. The application has the beneficial effects that the application is simple to operate and highly feasible, can be directly compatible with an existing assembly process, and can compensate for pressure of a non-bolt fastening region (a central region) of the electrolytic cell by using the auxiliary fastening device and the method, so as to realize effective pressure loading of the entire electrolytic cell and maintain components such as end plates and polar plates from being deformed and failed.

Description

Technical Field

[0001] This invention relates to the field of electrolytic cell fastening technology, and more particularly to an auxiliary fastening device and fastening method for electrolytic cells. Background Technology

[0002] Electrolysis of water to produce hydrogen is a reliable and green hydrogen production technology. As the demands for larger electrolyzers in practical applications continue to increase, the technology is constantly evolving. Whether it's the already mature alkaline electrolyzers and PEM electrolyzers, or the rapidly developing AEM and SOEC electrolyzers, the capacity of a single cell is continuously increasing. Alkaline electrolyzers have expanded from the initial 500 Nm³ per cell to 1000-2000 Nm³, and this trend shows further expansion. Other technologies are also exhibiting similar development trends.

[0003] An increase in the capacity of a single electrolytic cell inevitably means a simultaneous increase in the active area and the number of chambers, which places higher demands on the effective fastening of the electrolytic cell. Currently, the main methods used are surface sealing or line sealing, which typically involve a certain number of high-strength bolts surrounding the electrolytic cell for external or internal fastening, thereby achieving stress loading and maintenance. However, regardless of whether external or internal fastening is chosen, the core active area must be avoided. This means that when the active area is large or the number of chambers is high, due to the limitation of the stress-bearing area, the pressure is mainly concentrated near the bolts, while the core reaction area far from the bolts, and even the critical sealing area, may lack effective pressure due to the stress deformation of components such as end plates and electrodes, leading to increased contact resistance and seal failure.

[0004] Therefore, given the increasing demand for larger electrolytic cells, it is becoming increasingly important to add auxiliary fastening devices and methods to the central area of ​​the electrolytic cell (away from the bolt fastening area). Through auxiliary fastening, it is hoped that more effective fastening, internal contact and sealing of the electrolytic cell can be achieved.

[0005] Currently, to achieve the desired tightening effect and ideal contact and sealing, a press is typically used during assembly to apply additional pressure to the central area while simultaneously tightening the bolts on the electrolytic cell. However, when the press pressure is released, the force on the central area of ​​the electrolytic cell is less than that on the bolt-tightened area, which may cause warping deformation and other problems, leading to increased contact resistance and seal failure.

[0006] Currently, to avoid this risk, excessive torque is usually applied to the bolts in the hope of offsetting the unloading caused by deformation in the central area. However, this does not fundamentally solve the problem of warping in the central area and brings greater mechanical failure risk to the bolts and their main stress areas. Summary of the Invention

[0007] To overcome the aforementioned problems in the prior art, the present invention provides an auxiliary fastening device and fastening method for an electrolytic cell.

[0008] This invention discloses an auxiliary fastening device for an electrolytic cell, comprising: an outer support for providing support for the auxiliary fastening device; a force-applying component disposed on the outer support for applying pressure to the central region of the electrolytic cell; the force-applying component including at least one of a single-sided tray, a single-sided pressure block, or a double-sided pressure block; a driving component connected to the force-applying component for driving the force-applying component to move to adjust the pressure applied to the electrolytic cell; a detection component disposed at the connection between the force-applying component and the driving component for detecting the pressure value; and matching bolts for fixing the outer support to the electrolytic cell; the auxiliary fastening device compensates for pressure in the non-bolt-fastened areas of the electrolytic cell after the peripheral bolts of the electrolytic cell are tightened.

[0009] Based on this, the force-applying component includes multiple pressure blocks, which apply force independently or synchronously to the entire central area or some key areas of the electrolytic cell according to the structure and pressurization requirements of the electrolytic cell.

[0010] Based on this, the drive assembly includes a transmission mechanical component and a motor, the motor driving the force-applying component to move through the transmission mechanical component; the auxiliary fastening device also includes a control system, the control system controlling the operation of the motor according to the feedback signal of the detection component, so as to realize dynamic pressure compensation for the electrolytic cell.

[0011] Based on this, the outer support structure is a four-arm, six-arm, or higher strength structure.

[0012] Based on this, the auxiliary fastening device is configured to be installed vertically or horizontally; when installed vertically, the electrolytic cell is placed vertically on the single-sided tray or between the single-sided / double-sided pressure blocks; when installed horizontally, the electrolytic cell is placed horizontally between the single-sided / double-sided pressure blocks.

[0013] Based on this, an insulating component is provided on the end face of the force-applying component that contacts the electrolytic cell to prevent the formation of a conductive circuit between the auxiliary fastening device and the electrode plate or end plate of the electrolytic cell, and the withstand voltage rating of the insulating component is greater than the maximum operating voltage of the electrolytic cell.

[0014] Based on this, the control system executes adaptive pressure compensation logic. When the detection component detects that the pressure value is lower than a preset threshold, or receives a temperature change signal of the electrolytic cell from the temperature sensor, the control system controls the motor to drive the force application component to perform displacement compensation in order to maintain constant pressure.

[0015] Another aspect of the present invention discloses a fastening method using the aforementioned electrolytic cell-assisted fastening device, characterized by comprising the following steps:

[0016] S1: Place the electrolytic cell inside the auxiliary fastening device and mechanically fix the outer support to the electrolytic cell using matching bolts;

[0017] S2: Position the single-sided or double-sided pressure block according to the assembly requirements of the electrolytic cell;

[0018] S3: It adopts a stepped pressure loading method, which controls the force application component to apply pressure to the central area of ​​the electrolytic cell in stages through the drive component, and the pressure magnitude is fed back by the detection component;

[0019] S4: After the auxiliary pressurization is completed, the pressure is calibrated and dynamically adjusted until the target pressure value is reached.

[0020] Based on this, in step S3, the step-by-step pressure loading method is as follows: the pressure is increased in stages according to the symmetrical pressurization sequence, and the pressure increase each time is 0%-20% of the final target pressure value; after completing each stage of pressurization, it is stabilized for 0-20 minutes before entering the next pressurization stage, until the pressure is loaded to 100%.

[0021] Based on this, if the pressure drop value reported by the detection component exceeds the preset deviation within the stable time of each stage, the loading of the next stage will be paused and pressure will be replenished.

[0022] Based on this, in step S4, the steps for calibrating and dynamically adjusting the pressure are as follows: detect the pressure between each working pressure block; if the pressure difference is greater than the preset requirement value, adjust it through the drive component; check the torque value of the original fastening bolts of the electrolytic cell again; if it does not meet the design requirements, tighten the bolts again, and repeat the auxiliary pressurization process and the external bolt torque detection steps until both reach the target value.

[0023] Based on this, during the operation of the electrolytic cell, if the pressure of the pressing block is unloaded due to thermal expansion and contraction or disturbance of the transmission device, the pressure value is read by the detection component, and the control system controls the drive component to automatically replenish the pressure. The force application component only contacts the end plate of the electrolytic cell.

[0024] Compared with the prior art, the beneficial effects of the present invention are: the present invention is simple to operate, highly feasible, and directly compatible with existing assembly processes. By using auxiliary fastening devices and methods, pressure compensation is performed on the non-bolt fastening area (central area) of the electrolytic cell, thereby achieving effective pressure loading of the entire electrolytic cell and maintaining the end plates, electrode plates, and other components from deformation and failure; it has strong applicability and can be applied to all water electrolysis technology routes, requiring only parameter adjustments based on the specific electrolytic cell design dimensions and application conditions; it has low cost, low risk, does not generate additional risk points, and effectively avoids excessive pressure concentration in the bolt area. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0027] In the diagram: 1. Transmission mechanical components, 2. Motor, 3. Press block, 4. External support, 5. Electrolytic cell, 6. Single-sided tray. Detailed Implementation

[0028] The present 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 only for explaining the present invention and are not intended to limit the present invention.

[0029] Example 1

[0030] This embodiment provides an auxiliary fastening device suitable for vertical electrolytic cells, the structure of which is as follows: Figure 1 As shown, it includes an outer support 4, a force application component, a drive component, a detection component, and matching bolts.

[0031] The outer support 4 is a six-arm frame structure welded from high-strength steel. The six-arm design provides higher strength than the four-arm structure and is suitable for working conditions that require greater pressure.

[0032] The force-applying component adopts a combination of a single-sided tray and a single-sided pressure block. The electrolytic cell 5 is placed vertically, and its bottom is supported by a single-sided tray 6 fixed to the bottom of the outer support 4. Above the electrolytic cell 5, there are four single-sided pressure blocks 3, which are directly opposite the center area of ​​the end plate of the electrolytic cell 5. Each pressure block 3 has a 20mm thick polyimide insulating component embedded on the end face that contacts the electrolytic cell 5. Its withstand voltage rating is as high as 3000V, which is much greater than the maximum working voltage of the electrolytic cell, effectively preventing the formation of a conductive circuit.

[0033] The drive assembly consists of a servo motor 2 and a ball screw transmission mechanical component 1. Each pressure block 3 is driven by an independent servo motor 2 via a ball screw, which can achieve precise vertical displacement control.

[0034] The detection component is a high-precision pressure sensor, which is installed at the connection between each pressure block 3 and the ball screw to monitor and provide feedback on the pressure value in real time.

[0035] The control system is electrically connected to the servo motor 2 and the pressure sensor. The control system is configured to perform adaptive pressure compensation logic: when the pressure sensor detects that the pressure value is lower than the preset threshold, such as when the pressure drops due to thermal expansion and contraction, or when a signal is received from an external temperature sensor, the servo motor 2 will be automatically controlled to drive the pressure block 3 to perform micro-displacement compensation in order to maintain constant pressure.

[0036] Example 2

[0037] This embodiment provides an auxiliary fastening device suitable for horizontal electrolytic cells, the structure of which is as follows: Figure 2 As shown, unlike Embodiment 1, the device in this embodiment does not include a bottom tray, which reflects a different installation method.

[0038] The outer support 4 adopts an eight-arm reinforced frame structure to withstand greater counter-pressure. The electrolytic cell 5 is placed horizontally in the center of the device.

[0039] The force-applying assembly adopts a double-sided pressure block mode. On the left and right sides of the electrolytic cell 5, three sets of single-sided pressure blocks 3 are symmetrically arranged, for a total of six pressure blocks. The pressure blocks 3 on both sides can apply force to the entire central area or some key areas of the electrolytic cell 5 independently or simultaneously. Similarly, the contact end face of each pressure block 3 is also equipped with high-voltage-resistant insulating components.

[0040] The drive and detection components are similar to those in Embodiment 1, consisting of a servo motor 2, a ball screw transmission mechanical component 1, and a pressure sensor, which drive and monitor the horizontal movement and force applied by the six pressure blocks 3 on both sides to ensure balanced force application.

[0041] Example 3

[0042] This embodiment provides a fastening method for the electrolytic cell auxiliary fastening device based on any of the above embodiments, including the following steps;

[0043] S1: Taking the vertical type as an example, the electrolytic cell 5 is hoisted into the auxiliary fastening device, so that its bottom is placed stably on the single-sided tray 6 and centered. The outer support 4 and the base of the electrolytic cell 5 are mechanically locked with matching high-strength bolts to ensure that there is no relative displacement between the two during the subsequent pressurization process.

[0044] S2: According to the assembly requirements of the electrolytic cell 5, this embodiment selects the single-sided pressing block mode. Through the control system, the four pressing blocks 3 at the top are selected as working units, and the motor 2 is controlled to drive the pressing blocks 3 downward so that they gently contact the surface of the upper end plate of the electrolytic cell 5 to complete the initial positioning.

[0045] S3: Initiate the stepped pressurization program. The control system controls the four pressure blocks 3 to apply force synchronously in a symmetrical sequence (e.g., upper left → lower right → upper right → lower left). The pressure loading is divided into 5 stages, with each stage increasing the target pressure (e.g., 10 MPa) by 20% (i.e., 2 MPa). After each stage of pressurization is completed, the system automatically enters a 10-minute pressure holding and stabilization period. During this period, if the pressure drop value reported by the pressure sensor exceeds the preset deviation of 0.2 MPa, the next stage of loading is paused and a small amount of pressure is automatically added to ensure pressure stability before entering the next stage, until the total pressure reaches 100%.

[0046] S4: After all pressurization is complete, the system reads the values ​​from the four pressure sensors. If the pressure difference between any two pressure blocks 3 exceeds the preset requirement of 5%, the control system will automatically instruct the pressure block with the lower pressure to perform a slight displacement compensation until the pressure of all pressure blocks is balanced. Subsequently, the original fastening bolts around the electrolytic cell 5 are re-checked using an intelligent torque wrench. If the torque is not up to standard, they are retightened, and the auxiliary pressurization process of S3 is repeated until the central auxiliary pressure and the torque of the peripheral bolts both meet the design requirements.

[0047] After the electrolytic cell 5 is put into operation, the control system continuously monitors the pressure sensor data. When it detects that the pressure of the pressure block 3 has dropped due to thermal expansion and contraction or equipment vibration, the system will automatically trigger the pressure replenishment program, drive the motor 2 to adjust the position of the pressure block 3, and restore the pressure to the set value. Throughout the process, the force application component only contacts the end plate of the electrolytic cell 5 and does not involve the internal active area, so there is no risk of leakage.

[0048] In the description of this invention, it should be understood that the terms "coaxial," "bottom," "one end," "top," "middle," "other end," "upper," "side," "top," "inner," "front," "center," "both ends," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0049] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "screw-in," "pad," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0050] The foregoing description illustrates and describes preferred embodiments of the present invention. As previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. An auxiliary fastening device for an electrolytic cell, characterized in that, include: The outer bracket (4) is used to provide support for the auxiliary fastening device; A force-applying component is disposed on the peripheral support (4) for applying pressure to the central region of the electrolytic cell (5); the force-applying component includes at least one of a single-sided tray (6), a single-sided pressure block (3), or a double-sided pressure block; A driving component, connected to the force-applying component, is used to drive the force-applying component to move in order to adjust the pressure applied to the electrolytic cell (5); A detection component is disposed at the connection between the force application component and the drive component, and is used to detect the pressure value; Matching bolts are used to fix the outer support (4) to the electrolytic cell (5); The auxiliary fastening device is used to compensate for pressure in the non-bolt-fastened area of ​​the electrolytic cell (5) after the peripheral bolts of the electrolytic cell (5) are tightened.

2. The electrolytic cell auxiliary fastening device according to claim 1, characterized in that: The force-applying component includes multiple pressure blocks (3), which apply force independently or synchronously to the entire central area or some key areas of the electrolytic cell (5) according to the structure and pressurization requirements of the electrolytic cell (5).

3. The electrolytic cell auxiliary fastening device according to claim 1, characterized in that: The drive assembly includes a transmission mechanical component (1) and a motor (2). The motor (2) drives the force application component to move through the transmission mechanical component (1). The auxiliary fastening device also includes a control system. The control system controls the operation of the motor (2) according to the feedback signal of the detection component to achieve dynamic pressure compensation for the electrolytic cell (5).

4. The electrolytic cell auxiliary fastening device according to claim 1, characterized in that: The peripheral support (4) is a four-arm, six-arm or higher strength structure.

5. The electrolytic cell auxiliary fastening device according to claim 1, characterized in that: The auxiliary fastening device is configured to be installed vertically or horizontally; when installed vertically, the electrolytic cell (5) is placed vertically on the single-sided tray (6) or between the single-sided / double-sided pressure blocks; when installed horizontally, the electrolytic cell (5) is placed horizontally between the single-sided / double-sided pressure blocks.

6. The electrolytic cell auxiliary fastening device according to claim 1, characterized in that: An insulating component is provided on the end face of the force application component that contacts the electrolytic cell (5) to prevent the formation of a conductive circuit between the auxiliary fastening device and the electrode plate or end plate of the electrolytic cell (5), and the withstand voltage rating of the insulating component is greater than the maximum operating voltage of the electrolytic cell (5).

7. The electrolytic cell auxiliary fastening device according to claim 3, characterized in that: The control system executes adaptive pressure compensation logic. When the detection component detects that the pressure value is lower than the preset threshold, or receives the electrolytic cell temperature change signal fed back by the temperature sensor, the control system controls the motor (2) to drive the force application component to perform displacement compensation in order to maintain constant pressure.

8. A fastening method using the electrolytic cell auxiliary fastening device as described in any one of claims 1-7, characterized in that, Includes the following steps: S1: Place the electrolytic cell (5) inside the auxiliary fastening device and mechanically fix the outer bracket (4) to the electrolytic cell (5) with matching bolts; S2: Position the single-sided pressure block (3) or double-sided pressure block according to the assembly requirements of the electrolytic cell (5); S3: A stepped pressure loading method is adopted. The driving component controls the force application component to apply force to the central area of ​​the electrolytic cell (5) in stages, and the detection component provides feedback on the pressure magnitude. S4: After the auxiliary pressurization is completed, the pressure is calibrated and dynamically adjusted until the target pressure value is reached.

9. The fastening method according to claim 8, characterized in that: In step S3, the step-by-step pressure loading method is as follows: the pressure is increased in stages according to the symmetrical pressurization sequence, and the pressure increase each time is 0%-20% of the final target pressure value; after completing each stage of pressurization, it is stabilized for 0-20 minutes before entering the next pressurization stage, until the pressure is loaded to 100%.

10. The fastening method according to claim 9, characterized in that: If the pressure drop value reported by the detection component exceeds the preset deviation during the stable time of each stage, the loading of the next stage will be paused and pressure will be replenished.

11. The fastening method according to claim 8, characterized in that: In step S4, the steps for calibrating and dynamically adjusting the pressure are as follows: detect the pressure between each working pressure block (3). If the pressure difference is greater than the preset requirement value, adjust it through the drive component. Check the torque value of the original fastening bolt of the electrolytic cell (5) again. If it does not meet the design requirements, tighten the bolt again and repeat the auxiliary pressurization process and the external bolt torque detection steps until both reach the target value.

12. The fastening method according to claim 8, characterized in that: During the operation of the electrolytic cell (5), if the pressure of the pressure block (3) is unloaded due to thermal expansion and contraction or disturbance of the transmission device, the pressure value is read by the detection component and the control system controls the drive component to automatically replenish the pressure. The force application component only contacts the end plate of the electrolytic cell (5).

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