Automatic electric pile assembling equipment and assembling method

Abstract

The invention discloses an electric pile automatic assembling device and method, and relates to the technical field of automobile electric pile assembling device.The electric pile automatic assembling method comprises the steps that an electric pile stacking jig is conveyed to a feeding position of a lower end plate feeding assembly through a conveying belt; the lower end plate feeding assembly is used for placing a lower end plate on the electric pile stacking jig through driving; the bipolar plates and the membrane electrodes are sequentially and alternately stacked on the lower end plate through the automatic stacking assembly to form an electric pile stacking body; covering an upper end plate on the electric pile stacking body through an upper end plate feeding assembly; s4, pressing the stack stack in the step S4 through a pressing assembly to obtain a pressed stack; according to the invention, the laminated electric pile is conveyed to the air tightness detection position through the conveying belt, air tightness detection is carried out on the electric pile through the air tightness detection assembly, and whether the electric pile is qualified or unqualified is automatically judged according to the detection result, so that the electric pile assembling, stacking and laminating accuracy and detection automatic shunting can be ensured, and the stability in the electric pile assembling process is improved.

Description

Technical Field

[0001] This invention relates to the field of automotive fuel cell stack assembly equipment technology, and in particular to an automated fuel cell stack assembly equipment and assembly method. Background Technology

[0002] New energy vehicles use fuel cell systems as their main power source. The fuel cell stack is the core component of the fuel cell system. It converts hydrogen and oxygen from the air into electrical energy through electrochemical reactions and continuously provides stable power to the drive motor to achieve the power output of the entire vehicle.

[0003] A fuel cell stack typically consists of a multi-layered structure including a lower end plate, bipolar plates, membrane electrode assembly (MEA), and an upper end plate. It is the core component of fuel cells or other electrochemical energy conversion systems. Through the conductive, mass transfer, and sealing structures between the layers, it enables the continuous electrochemical reaction, thereby outputting stable electrical energy.

[0004] In existing fuel cell stack assembly technologies, the assembly process typically involves stacking, pressing, and testing multiple layers, including the lower end plate, bipolar plates, membrane electrode assembly (MEA), and upper end plate. Each step relies on independent processes, requiring a large number of stacks, high alignment accuracy between layers, and stable and consistent pressing pressure and pressure curves. However, existing assembly processes commonly suffer from asynchronous stacking, leading to misalignment between the stacked bipolar plates and MEAs. Furthermore, the airtightness testing process in the finished product inspection stage still relies on independent testing equipment for unit-by-unit testing, resulting in low testing efficiency. This prevents automatic judgment and sorting of test results, causing delays in the rework process and limiting the overall smoothness of the production line. Summary of the Invention

[0005] The purpose of this invention is to provide an automated assembly method for fuel cell stacks, which solves the problem of insufficient stability in the existing fuel cell stack assembly process due to stacking misalignment and detection lag.

[0006] To achieve this objective, the present invention adopts the following technical solution: According to a first aspect, the present invention provides an automated assembly method for fuel cell stacks, comprising: Step S1: The stacking fixture is conveyed to the loading position of the lower end plate loading assembly via a conveyor belt; Step S2: The lower end plate loading assembly places the lower end plate onto the stacking fixture via a drive. Step S3: The bipolar plates and membrane electrodes are alternately stacked on the lower end plate in sequence using an automatic stacking assembly to form an electrode stack. Step S4: Cover the stacked body of the fuel cell stack with the upper end plate loading assembly; Step S5: Press the stacked battery pack from step S4 using a pressing assembly to obtain a pressed battery pack. Step S6: The pressed fuel cell stack is conveyed to the airtightness testing station via a conveyor belt, and the airtightness of the fuel cell stack is tested by the airtightness testing component. The result is automatically determined as qualified or unqualified.

[0007] Preferably, in step S51, the pre-compression stage, an initial pressure is first applied to the stack body, and the contact surfaces between the bipolar plates, membrane electrodes and end plates inside the stack body are brought into contact by gradually increasing the pressure but not exceeding the set pre-compression limit. Step S52: After the pre-compression stabilization is completed, the main pressure stage begins. The press increases the pressure to the pressure required for pressing according to the set target pressure curve, and achieves closed-loop regulation through real-time feedback from the pressure sensor. The pressure rise rate in the main pressure stage is higher than that in the pre-compression stage, which further compresses the stack on the basis of stable bonding, ensuring that the sealing structure, conductive contact interface and overall dimensions between each functional layer meet the design requirements, and completing the key forming process of the fuel cell stack. Step S53: After the pressing pressure reaches the main pressure target value, a constant pressing pressure is maintained to stabilize the sealing structure and fastening interface. During this stage, the control system continuously monitors the pressure changes. If the pressure fluctuation threshold is exceeded, real-time adjustments are made to ensure that the pressing effect meets the fuel cell stack assembly quality requirements.

[0008] Preferably, in step 51, the pressing pressure is gradually increased from 0 MPa to 1.0-2.0 MPa at a preset pressure increase rate, with the pressure increase rate controlled at 0.05-0.1 MPa / s, and the pressure is maintained stably for 3-5 seconds.

[0009] Preferably, the pressing pressure in step 52 is 5-8 MPa, the pressure rise rate is controlled at 0.2-0.4 MPa / s, and the pressure is maintained stably for 5-10 seconds.

[0010] Preferably, the pressing pressure in step 53 is 5-8 MPa, and the pressure is maintained stably for 10-20 seconds. During this period, the system continuously adjusts the pressure through pressure feedback to keep the pressure fluctuation not exceeding ±0.05 MPa.

[0011] Preferably, after step 6, the following steps are also included: Step S7: When the test result is unqualified, the fuel cell stack is automatically transported to the rework station for rework via a conveyor; when the test result is qualified, the fuel cell stack is transported to the manual locking rod / screw fastening station for structural fastening via a conveyor. Step S8: The secured fuel cell stack is automatically transferred to the fuel cell stack flipping and unloading process and the fuel cell stack is removed by a cantilever crane. Step S9: The fuel cell stack taken out in step S8 is sent to the fuel cell stack depressurization and unloading process by a tilting trolley to complete the assembly.

[0012] Preferably, in step 6, the airtightness detection component uses helium detection, air pressurization, or negative pressure maintenance to detect the leakage rate of the fuel cell casing, and the control system automatically makes a pass / fail judgment based on the measured leakage value.

[0013] Preferably, in step 8, the manual locking rod / screw fastening station is connected to the downstream fuel cell stack flipping station via an automatic conveyor line, and the fuel cell stack attitude is automatically determined by a position recognition system.

[0014] According to a second aspect, the present invention provides an automated fuel cell stack assembly device, which employs the automated fuel cell stack assembly method described in the first aspect, comprising: a lower end plate loading assembly, an automatic stacking assembly, an upper end plate loading assembly, a pressing assembly, and an airtightness detection assembly; the lower end plate loading assembly is used to automatically transport the lower end plate from the hopper and place it onto the fuel cell stacking fixture; the lower end plate loading assembly is connected to the outer surface of the automatic stacking assembly; the automatic stacking assembly is used to alternately stack bipolar plates and membrane electrodes on the lower end plate to obtain a fuel cell stack body; the upper end plate loading assembly is used to place the upper end plate on top of the fuel cell stack body; the pressing assembly is used to perform multi-stage controlled pressing on the fuel cell stack body with the loading plate placed thereon to obtain a pressed fuel cell stack; the airtightness detection assembly is used to detect the airtightness inside the pressed fuel cell stack.

[0015] Compared with the prior art, the present invention has the following beneficial effects: By constructing a complete automated assembly process, from loading the stacking jig, automatically placing the upper and lower end plates, automatically completing the stacking, automatically executing the pressing, to the airtightness detection and automatic judgment, the stacking accuracy and pressing quality of the fuel cell stack are guaranteed, the assembly efficiency is improved, and the offset error and quality inconsistency caused by manual intervention are reduced. The automatic airtightness detection and judgment significantly improves the detection efficiency and judgment accuracy, avoids production cycle delays, and improves the overall stability, reliability and production line smoothness of the fuel cell stack assembly process. Attached Figure Description

[0016] To more 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0018] Figure 1 A flowchart illustrating an automated fuel cell stack assembly method provided in an embodiment of the present invention; Figure 2 This is a structural schematic diagram of an automated fuel cell stack assembly device provided in an embodiment of the present invention.

[0019] Illustrations: 1. Lower end plate loading assembly; 2. Automatic stacking assembly; 3. Upper end plate loading assembly; 4. Pressing assembly; 5. Air tightness detection assembly; 6. Conveyor belt. Detailed Implementation

[0020] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0021] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0022] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] refer to Figure 1 - Figure 2 As shown, the first aspect of this invention provides an automated assembly method for fuel cell stacks, comprising: Step S1: The electric stack stacking fixture is conveyed to the loading position of the lower end plate loading assembly 1 via the conveyor belt 6; Step S2: The lower end plate loading assembly 1 places the lower end plate onto the stacking fixture of the electric stack by driving it. Step S3: The bipolar plates and membrane electrodes are alternately stacked on the lower end plate in sequence using the automatic stacking assembly 2 to form an electrode stack. Step S4: The upper end plate is covered onto the stacked body of the fuel cell stack using the upper end plate loading assembly 3; Step S5: Press the stacked battery pack from step S4 using a pressing assembly to obtain a pressed battery pack. Step S6: The pressed fuel cell stack is conveyed to the airtightness testing station via a conveyor belt, and the airtightness of the fuel cell stack is tested by the airtightness testing component. The result is automatically determined as qualified or unqualified.

[0024] First, in step S1, the unloaded electrode stacking fixture is conveyed to the loading station corresponding to the lower end plate loading assembly 1 via conveyor belt 6, so that the stacking fixture accurately stops at the loading station of the lower end plate loading assembly 1, providing a reference platform for the subsequent lower end plate placement and stacking process. Then, in step S2, the lower end plate loading assembly 1, driven by the control system, grabs or clamps a lower end plate from the lower end plate hopper and accurately places it on the electrode stacking fixture, so that the lower end plate establishes a positioning reference relative to the stacking fixture. Next, in step S3, the automatic stacking assembly 2 sequentially picks up bipolar plates and membrane electrodes according to the set program, and stacks them alternately on the lower end plate in a predetermined order until the target number of plates set by the system is reached, thereby forming an electrode stack with the designed number of layers and structural order, ensuring the positional accuracy and stacking consistency of each layer of components. In step S4, the upper end plate loading assembly 3 covers the lower end plate in a similar loading and positioning manner as the lower end plate. The stack is placed on top of the fuel cell stack, forming a complete end plate constraint structure at both ends, providing boundary conditions for subsequent overall pressing. In step S5, the pressing component 4 automatically presses the fuel cell stack on the stacking fixture, applying a quantitative pressure to the stack according to preset pressing parameters. This allows the bipolar plates, membrane electrodes, and sealing structure to be pressed and shaped under the constraint of the upper and lower end plates, forming a fuel cell assembly with a stable structure and preload. Finally, in step S6, the pressed fuel cell is introduced into the airtightness detection component 5 via the conveyor belt 6. The leakage of the fuel cell shell is tested using a preset detection method. The control system automatically determines whether the fuel cell is a qualified or unqualified part based on the comparison between the measured leakage value and the set threshold, providing a basis for subsequent automatic diversion, rework, or removal from the production line. This constitutes a continuous assembly process from loading the stacking fixture, stacking, pressing, and automatic airtightness determination.

[0025] refer to Figure 1 - Figure 2As shown, step S5 specifically includes: adjusting the pressing pressure in real time based on the closed-loop control method of pressure sensor feedback, and using multi-segment pressure curves to execute the pre-pressing, main pressure and pressure holding processes; Step S51, the pre-compression stage, firstly, an initial pressure is applied to the stack body, and by gradually increasing but not exceeding the set pre-compression upper limit, the contact surfaces between the bipolar plates, membrane electrodes and end plates inside the stack body are brought together; the compression pressure in step 51 is increased from 0 MPa to 1.0 to 2.0 MPa at a preset pressure increase rate, and the pressure increase rate is controlled at 0.05 to 0.1 MPa / s, and the pressure is maintained stably for 3 to 5 seconds; First, in the pre-compression stage (step S51), the pressing component 4 loads the stack body with a low initial pressure. The pressing pressure is increased from 0 MPa to 1.0-2.0 MPa at a preset pressure increase rate, and the pressure increase rate is controlled at 0.05-0.1 MPa / s. After the pressure reaches the set pre-compression upper limit, a stable pressure is maintained for 3-5 seconds. The contact surfaces between the bipolar plates, membrane electrodes and end plates are gradually brought together by the low-pressure progressive loading method, eliminating residual gaps inside the stack body and avoiding stack misalignment caused by high-pressure instantaneous loading, thus providing a stable force foundation for the subsequent main pressure stage. It should be noted that when the pressing pressure in step S51 is lower than 1.0 MPa, the layers inside the stack fail to achieve the ideal degree of compression, resulting in the bipolar plates, membrane electrodes, and end plates inside the stack not being able to adhere effectively. This leads to tiny gaps or incomplete contact between layers, affecting the stack's sealing performance, conductive contact performance, and overall structural stability. This will result in poor sealing performance of the stack and affect the pass rate of the airtightness test. When the pressing pressure in step S51 is higher than 2.0 MPa, excessive load will be applied to the membrane electrodes and sealing structure before the initial adhesion is completed, causing the flexible components to enter the plastic deformation stage prematurely, resulting in local pressure damage, deformation of the sealing structure, or interlayer slippage, thereby damaging the subsequent molding quality.

[0026] If the pressure rise rate in step S51 is less than 0.05 MPa / s, the loading process is too slow. The void elimination and interface bonding that should have been completed in the pre-compression stage will become inefficient, resulting in the inability to form a stable and uniform force base in the pre-compression stage. As a result, the main compression stage still needs to bear the bonding function, causing the main pressure fluctuation to increase, the curve to be unstable, and interlayer micro-movement to occur, affecting the consistency of subsequent compression. If the pressure rise rate is greater than 0.1 MPa / s, the excessively fast loading speed will apply too large instantaneous impact to the bipolar plates and membrane electrodes that have not yet established a stable frictional contact relationship, causing interlayer slippage or misalignment. At the same time, the rapid pressure will also cause the membrane electrodes and sealing structure to suffer local pressure damage or non-uniform deformation due to sudden force changes, affecting the sealing performance and structural stability of the stack. If the pressure holding time in step S51 is less than 3 seconds, the interfaces between the bipolar plates, membrane electrodes, and end plates inside the stack are not fully bonded, the initial gaps are not fully eliminated, and the pressure is not uniformly transmitted between the layers. This means that the main pressure stage needs to continue pressing on an unstable stress basis, which can easily lead to increased fluctuations in the main pressure, micro-displacement between layers, or local stress concentration, thus affecting the final molding consistency of the stack. If the holding time is more than 5 seconds, the pre-pressing stage will last too long, causing the flexible membrane electrodes and seals to be subjected to excessive compression before entering the main pressure stage. This can easily lead to unnecessary creep deformation or chronic compression fatigue, and will also reduce the production cycle without improving the actual pressing effect.

[0027] refer to Figure 1 - Figure 2 As shown, in step S52, after the pre-compression stabilization is completed, the main pressure stage begins. The press increases the pressure to the pressure required for pressing according to the set target pressure curve, and achieves closed-loop regulation through real-time feedback from the pressure sensor. The pressure rise rate in the main pressure stage is higher than that in the pre-compression stage, which further compresses the stack on the basis of stable adhesion, ensuring that the sealing structure, conductive contact interface and overall dimensions between each functional layer meet the design requirements, and completing the key forming process of the fuel cell stack. The pressing pressure in step 52 is 5-8 MPa, and its pressure rise rate is controlled at 0.2-0.4 MPa / s, and the pressure is maintained stably for 5-10 seconds.

[0028] The main pressure stage then begins (step S52). The pressing assembly 4 continues to increase the pressing pressure according to the set main pressure curve, raising it to the 5–8 MPa required for final pressing. During this process, the pressure rise rate increases to 0.2–0.4 MPa / s. After reaching the target main pressure, it is maintained for 5–10 seconds. Under the main pressure, the stacked bodies are further compressed on top of their already fully bonded state, causing the sealing structure to undergo designed deformation. The conductive interfaces of each layer achieve the required contact, ensuring the dimensional accuracy, sealing reliability, and structural stability of the fuel cell stack. The entire main pressure process relies on real-time feedback information from pressure sensors for closed-loop regulation to ensure the stability and controllability of the pressure curve.

[0029] It should be noted that if the pressure in step S52 is lower than 5MPa, due to insufficient clamping force, the bipolar plates, membrane electrodes, and sealing structure cannot reach the designed compression amount, and there will still be small gaps at the interlayer contact interface. The necessary deformation of the sealing gasket cannot be completed, making the overall sealing performance, conductive contact impedance, and geometric dimensions of the fuel cell stack unstable. This can lead to unqualified airtightness test, high internal impedance, or leakage and structural loosening during long-term operation. If the main pressure is higher than 8MPa, the stack will be subjected to a compression load exceeding the design value. The flexible membrane electrodes and sealing components will be over-compressed or locally damaged, resulting in permanent deformation of the sealing structure, damage to the conductive interface, inconsistent material rebound, and even warping of the stack edges or loss of overall thickness control, further affecting the consistency, durability, and safety of the fuel cell stack's subsequent performance. If the pressure rise rate in step S52 is less than 0.2 MPa / s, the bonding process of each layer of the stack will be insufficient due to the slow pressure increase, resulting in excessive time, increased production cycle, and the stack will not be able to achieve uniform pressure distribution within an appropriate time, thus affecting the efficiency and accuracy of the subsequent main pressure stage. If the pressure rise rate is greater than 0.4 MPa / s, excessive impact force will be applied to the stack before a stable contact interface is established, which may easily lead to slippage or misalignment between the stack layers, or even damage to the flexible membrane electrode and sealing structure, affecting the sealing and conductive contact performance of the stack, thereby affecting the long-term stability and reliability of the stack.

[0030] If the pressure holding time in step S52 is less than 5 seconds, the internal material has not yet completed the necessary stress release and stable deformation. The bipolar plate, membrane electrode, and sealing structure enter the depressurization stage before being fully compressed and shaped, resulting in residual voids or incomplete compaction in the stack. This leads to unstable stack thickness and insufficient compression of the sealing structure, which in turn causes the airtightness test to fail or the risk of leakage during subsequent operation. If the pressure holding time exceeds 10 seconds, the flexible membrane electrode and sealing components will be subjected to excessively long-term compressive loads under high pressure, resulting in unnecessary creep deformation or fatigue effects. At the same time, it prolongs the main pressure cycle and reduces the production cycle time, without significantly improving the pressing quality. In fact, the excessive compression of the material may even affect its resilience and long-term stability.

[0031] refer to Figure 1 - Figure 2As shown, in step S53, after the pressing pressure reaches the main pressure target value, a constant pressing pressure is maintained to stabilize the sealing structure and fastening interface. During this stage, the control system continuously monitors the pressure changes. If the pressure fluctuation threshold is exceeded, real-time adjustments are made to ensure that the pressing effect meets the fuel cell stack assembly quality requirements. The pressing pressure in step 53 is 5-8 MPa, and the pressure is maintained stably for 10-20 seconds. During this period, the system continuously adjusts through pressure feedback to keep the pressure fluctuation not exceeding ±0.05 MPa.

[0032] After the main pressure stabilizes, the pressing process enters the pressure holding stage. During this stage, a constant pressing pressure of 5–8 MPa is maintained for 10–20 seconds. The control system continuously monitors pressure changes, and any minor fluctuations are compensated in real-time by the servo system, ensuring that pressure fluctuations are always controlled within ±0.05 MPa. The purpose of the pressure holding stage is to allow the internal materials of the stack to gradually stabilize and deform, release residual stress, ensure the sealing structure and fastening interface are fully formed, and improve the dimensional stability of the finished fuel cell stack and the pass rate of subsequent airtightness testing. After the pressure holding is completed, the pressing assembly 4 depressurizes according to a preset method and transports the pressed fuel cell stack to the next airtightness testing station.

[0033] If the holding pressure in step S53 is lower than 5.5 MPa, it will not be able to provide sufficient clamping force to the contact interface between the membrane electrode, sealing gasket and bipolar plate, resulting in insufficient necessary compression of the sealing structure, failure of the interface contact impedance to meet design requirements, and residual micro-gaps or incomplete compaction in the stack. This will lead to leakage or unstable electrical performance in the gas tightness test of the formed fuel cell stack. If the holding pressure is higher than 8.5 MPa, the flexible membrane electrode and sealing components will be subjected to long-term compressive stress exceeding the design range, which may easily cause over-compression, permanent deformation or damage to the interface material. This will prevent the sealing structure from rebounding normally after depressurization, leading to sealing degradation or structural stress concentration problems during long-term use of the fuel cell stack. If the pressure fluctuation in step S53 is lower than the control capability of ±0.05MPa, that is, the actual fluctuation is greater than this range, it will cause uneven stress on each layer of the stack during the pressure holding process. This will cause fluctuations in the pressure transmission of the bipolar plate, membrane electrode and sealing structure during the forming process, resulting in local stress concentration, insufficient compaction or over-compression in some areas. This will make it difficult to maintain consistency in the thickness, sealing deformation and conductive contact state after final pressing, directly affecting the stability of airtightness and electrical performance. If the pressure fluctuation control requirement is higher than ±0.05MPa, that is, the control range is set to a more stringent minimum fluctuation, the pressing system needs to frequently perform high-frequency adjustments to maintain such a small pressure change. This will cause the servo pressure system to be in an over-response state, which can easily cause mechanical vibration or pressure regulation overshoot of the press execution unit, or even cause repeated loading in the form of micro-vibration on the flexible membrane electrode and sealing structure, resulting in minor damage or fatigue during the pressure holding process.

[0034] refer to Figure 1 - Figure 2 As shown, in step 6, the airtightness detection component 5 uses helium detection, air pressurization or negative pressure maintenance to detect the leakage rate of the fuel cell casing, and the control system automatically makes a pass / fail judgment based on the measured leakage value.

[0035] When high leakage sensitivity is required or screening for minute leaks is necessary, helium detection is used. This involves introducing helium gas at a certain pressure into the fuel cell stack and using a helium mass spectrometer to monitor changes in helium concentration outside the casing or in a dedicated leak detection chamber, thereby accurately calculating the leakage rate of the fuel cell stack casing. When both detection efficiency and cost are critical, air pressurization can be used. This involves introducing compressed air into the fuel cell stack casing and raising it to a set test pressure. A pressure sensor monitors the pressure decay over a certain period of time, and the leakage rate is calculated from the pressure change. When it is inconvenient to pressurize the inside or when an external sealed chamber is suitable for detection, a negative pressure maintenance method can be used. The detection chamber covering the fuel cell stack is evacuated to a negative pressure, and the vacuum level is monitored over a set time to determine whether a leak exists in the fuel cell stack casing and the level of the leak. All three detection methods transmit the real-time measured leakage value or equivalent leakage amount to the control system, which then compares it with a pre-set leakage rate threshold and automatically makes a pass / fail determination.

[0036] Step S7: When the test result is unqualified, the fuel cell stack is automatically transported to the rework station for rework via a conveyor; when the test result is qualified, the fuel cell stack is transported to the manual locking rod / screw fastening station for structural fastening via a conveyor; Step S8: The fastened fuel cell stack is automatically transferred to the fuel cell stack flipping and unloading process and the fuel cell stack is taken out by a cantilever crane; Step S9: The fuel cell stack taken out in Step S8 is sent to the fuel cell stack depressurization and unloading process via a flipping trolley to complete the assembly.

[0037] After the airtightness testing component 5 completes the detection of the fuel cell stack housing leakage rate, it uploads the test results to the control system in real time. The control system determines whether each fuel cell stack is qualified or unqualified based on a preset leakage rate threshold. When the determination result is unqualified, the diversion mechanism on the conveyor line is activated under the command of the control system to guide the fuel cell stack to the rework branch, so that the fuel cell stack automatically enters the rework station along the conveyor. At the rework station, specialized personnel or tooling inspect and repair the leakage points to prevent unqualified fuel cell stacks from continuing to flow into subsequent assembly stages. When the determination result is qualified, the fuel cell stack continues to move forward along the main conveyor line and automatically enters the locking rod / screw. At the fastening station, manual labor combined with positioning fixtures is used to final tighten the tie rods or shell bolts at both ends of the fuel cell stack to ensure that the internal stacked components can maintain reliable axial preload and structural stability under long-term operating conditions. After fastening, the fuel cell stack is driven by the conveyor mechanism to enter the flipping and removal area corresponding to step S8. The flipping device connected to the conveyor line flips the fuel cell stack to achieve a spatial posture that is easy to remove from the line and transport. The fastened fuel cell stack is safely lifted and transferred by the cantilever crane set above the flipping station, and the fuel cell stack is transferred from the original conveyor line station to the downstream buffer or turnover position. In step S9, to facilitate subsequent depressurization and offline operations, a cantilever crane or intermediate turnover platform places the fuel cell stack onto a tilting trolley. The tilting trolley then transports the fuel cell stack to the fuel cell stack depressurization and offline process along a predetermined route. In this process, the internal pressure of the fuel cell stack is released in a controlled manner, and the final offline processing is completed.

[0038] refer to Figure 2 As shown, a second aspect of the present invention provides an automated assembly equipment for fuel cell stacks, comprising: a lower end plate loading assembly 1, an automatic stacking assembly 2, an upper end plate loading assembly 3, a pressing assembly 4, and an airtightness detection assembly 5; the lower end plate loading assembly 1 is used to automatically transport the lower end plate from the hopper and place it onto the fuel cell stacking fixture; the lower end plate loading assembly 1 is connected to the outer surface of the automatic stacking assembly 2; the automatic stacking assembly 2 is used to alternately stack bipolar plates and membrane electrodes on the lower end plate to obtain a fuel cell stack body; the upper end plate loading assembly 3 is used to place the upper end plate on top of the fuel cell stack body; the pressing assembly 4 is used to perform multi-stage controlled pressing on the fuel cell stack body with the loading plate placed thereon to obtain a pressed fuel cell stack; the airtightness detection assembly 5 is used to detect the airtightness inside the pressed fuel cell stack.

[0039] The electrode stacking fixture is placed on conveyor belt 6, and then conveyed to the lower end plate loading assembly 1 via conveyor belt 6. The lower end plate loading assembly 1 removes the lower end plate from its own hopper and places it on the electrode stacking fixture. Since the lower end plate loading assembly 1 is connected to the outer surface of the automatic stacking assembly 2, the conveyor belt 6 transports the electrode stacking fixture with the lower end plate to the automatic stacking assembly 2. The automatic stacking assembly 2, through its visual positioning, mechanical gripping, and precise alignment mechanism, alternately stacks the bipolar plates and membrane electrodes on the lower end plate in a preset order. After obtaining the fuel cell stack, the conveyor belt 6 continues to transport the fuel cell stack jig with the fuel cell stack to the upper plate loading assembly 3, so that the upper plate loading assembly 3 automatically transports the upper plate in its own hopper and places it on top of the fuel cell stack. Then the conveyor belt 6 transports the fuel cell stack to the pressing assembly 4, so that the pressing assembly 4 uses a servo control system to adjust the pressing force, pressing speed and pressing stroke, and completes the pressing of the fuel cell stack through pre-pressing, constant pressure and holding pressure stages, so that the bipolar plates, membrane electrodes and sealing components are bonded together, thereby forming the fuel cell stack assembly. After the fuel cell stack is pressed, it is conveyed by conveyor belt 6 to the airtightness testing component 5. This component is used to test the airtightness of the fuel cell stack after pressing. By filling the fuel cell stack channel with gas and monitoring its pressure change, it can quickly determine whether there are any leaks inside the fuel cell stack, so as to ensure that the assembled fuel cell stack meets the sealing reliability requirements. The test results of the airtightness testing component 5 can be used as the basis for determining whether the fuel cell stack can enter the next production process, thereby realizing the closed-loop quality control of the production process.

[0040] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An automated assembly method for fuel cell stacks, characterized in that, include: Step S1: The electric stack stacking fixture is conveyed to the loading position of the lower end plate loading assembly (1) via the conveyor belt (6); Step S2: The lower end plate loading assembly (1) places the lower end plate onto the stacking fixture by driving; Step S3: The bipolar plates and membrane electrodes are alternately stacked on the lower end plate in sequence using the automatic stacking assembly (2) to form an electrode stack; Step S4: Cover the stacked body with the upper end plate using the upper end plate loading assembly (3); Step S5: Press the stacked body of the fuel cell stack in step S4 using the pressing assembly (4) to obtain a pressed fuel cell stack; Step S6: The pressed fuel cell stack is transported to the airtightness testing position via conveyor belt (6), and the airtightness of the fuel cell stack is tested by the airtightness testing component (5). The result is automatically determined to be qualified or unqualified.

2. The automated assembly method for fuel cell stacks according to claim 1, characterized in that, Step S5 specifically includes: Step S51, Pre-compression stage: First, an initial pressure is applied to the stack body. By gradually increasing the pressure but not exceeding the set pre-compression limit, the contact surfaces between the bipolar plates, membrane electrodes and end plates inside the stack body are brought into contact. Step S52: After the pre-compression stabilization is completed, the main pressure stage begins. The press increases the pressure to the pressure required for pressing according to the set target pressure curve, and achieves closed-loop regulation through real-time feedback from the pressure sensor. The pressure rise rate in the main pressure stage is higher than that in the pre-compression stage, which further compresses the stack on the basis of stable bonding, ensuring that the sealing structure, conductive contact interface and overall dimensions between each functional layer meet the design requirements, and completing the key forming process of the fuel cell stack. Step S53: After the pressing pressure reaches the main pressure target value, a constant pressing pressure is maintained to stabilize the sealing structure and fastening interface. During this stage, the control system continuously monitors the pressure changes. If the pressure fluctuation threshold is exceeded, real-time adjustments are made to ensure that the pressing effect meets the fuel cell stack assembly quality requirements.

3. The automated assembly method for fuel cell stacks according to claim 2, characterized in that, In step 51, the pressing pressure is gradually increased from 0 MPa to 1.0-2.0 MPa at a preset pressure increase rate, with the pressure increase rate controlled at 0.05-0.1 MPa / s, and the pressure is maintained stably for 3-5 seconds.

4. The automated assembly method for fuel cell stacks according to claim 2, characterized in that, The pressing pressure in step 52 is 5-8 MPa, the pressure rise rate is controlled at 0.2-0.4 MPa / s, and the pressure is maintained stably for 5-10 seconds.

5. The automated assembly method for fuel cell stacks according to claim 2, characterized in that, In step 53, the pressing pressure is 5-8 MPa, and the pressure is maintained stably for 10-20 seconds. During this period, the system continuously adjusts through pressure feedback to keep the pressure fluctuation not exceeding ±0.05 MPa.

6. The automated assembly method for fuel cell stacks according to claim 1, characterized in that, Following step 6, the following is also included: Step S7: When the test result is unqualified, the fuel cell stack is automatically transported to the rework station for rework via a conveyor; when the test result is qualified, the fuel cell stack is transported to the manual locking rod / screw fastening station for structural fastening via a conveyor. Step S8: The secured fuel cell stack is automatically transferred to the fuel cell stack flipping and unloading process and the fuel cell stack is removed by a cantilever crane. Step S9: The fuel cell stack taken out in step S8 is sent to the fuel cell stack depressurization and unloading process by a tilting trolley to complete the assembly.

7. The automated assembly method for an electric fuel cell stack according to claim 1, characterized in that, In step 6, the airtightness detection component (5) uses helium detection, air pressurization or negative pressure maintenance to detect the leakage rate of the fuel cell casing, and the control system automatically makes a pass / fail judgment based on the measured leakage value.

8. The automated assembly method for an electric fuel cell stack according to claim 6, characterized in that, In step 8, the manual locking rod / screw fastening station is connected to the downstream fuel cell stack flipping station via an automatic conveyor line, and the position recognition system automatically determines the fuel cell stack attitude.

9. An automated fuel cell stack assembly device, wherein the automated fuel cell stack assembly device employs the automated fuel cell stack assembly method according to any one of claims 1 to 8, characterized in that, include: The lower end plate loading assembly (1), the automatic stacking assembly (2), the upper end plate loading assembly (3), the pressing assembly (4), and the airtightness detection assembly (5) are used to automatically transport the lower end plate from the hopper and place it on the electric stacking fixture; the lower end plate loading assembly (1) is connected to the outer surface of the automatic stacking assembly (2); The automatic stacking assembly (2) is used to alternately stack bipolar plates and membrane electrodes on the lower end plate to obtain a stacked battery; the upper end plate loading assembly (3) is used to place the upper end plate on top of the stacked battery; the pressing assembly (4) is used to perform multi-stage controlled pressing on the stacked battery with the loading plate to obtain a pressed battery; the airtightness detection assembly (5) is used to detect the airtightness inside the pressed battery.

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