Hydrogen fuel cell stack assembly method and system based on edge geometric feature precision constraint

Abstract

The invention relates to a hydrogen fuel cell stack assembly method and system based on edge geometric feature precision constraint, and the method comprises the steps: obtaining assembly information of a fuel cell stack, controlling pressurization equipment according to the assembly information, and stacking all assemblies of the fuel cell stack layer by layer; in the layer-by-layer stacking process, in response to bipolar plate stacking and pressure application completion, the size deviation of the edge of the stacked electric pile is calculated by scanning the edge of the stacked electric pile; based on the edge size deviation of the stacked electric piles, predicting a deviation distribution interval of subsequent stacking by constructing an electric pile assembly deviation transfer model; and based on the predicted deviation distribution interval of subsequent stacking, judging whether the fuel cell stack is located in the stack deviation limit containing interval, if so, continuing stacking, and if not, stopping stacking, and storing the parameters of the fuel cell stack which is stacked completely. Compared with the prior art, the invention has the advantages of high flexibility in the stack assembly process, suitability for batch and high-quality production requirements of fuel cell stacks, and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen fuel cell stack assembly, and in particular to a hydrogen fuel cell stack assembly method and system based on edge geometric feature accuracy constraints. Background Art

[0002] Hydrogen energy is abundant in sources, green and low-carbon, and is one of the important carriers of global energy transformation and development. Hydrogen fuel cells convert the chemical energy of hydrogen and oxygen directly into electrical energy, breaking through the upper limit of fuel engine conversion efficiency and becoming a clean and efficient way to use hydrogen energy. Hydrogen fuel cell monomers are composed of metal bipolar plates, sealing rubber and membrane electrode assemblies. Usually, the output voltage of a single hydrogen fuel cell is low. In order to improve the power generation capacity of hydrogen fuel cells, a large number of single cells need to be stacked and connected in series to form a high-power stack.

[0003] The assembly process of hydrogen fuel cell stacks includes processes such as material removal, stacking, and pressing. At a specific workstation, the bipolar plates, sealing rubbers, membrane electrodes and other stack components are stacked in sequence by hand or mechanical equipment. Hundreds of battery cells are assembled in series by stacking to form a large stack, and then pressed by a press to control the assembly pressure or assembly displacement. Finally, fastening bolts are installed around the end plate, and other spare parts are configured to complete the final assembly of the stack. During the assembly process, deviations in all directions of the stack are constantly accumulating. The deviations come from many aspects. On the one hand, they come from the manufacturing errors of the various parts of the stack, such as bipolar plates and sealing rubbers. On the other hand, they come from positioning errors and errors caused by the slippage of parts under compression loads.

[0004] To achieve accurate stacking of the various parts of a hydrogen fuel cell stack, we cannot rely solely on improving the processing accuracy of the parts, but must also rely on assembly process technology to a certain extent. Chinese Patent Application Publication No. CN117039089A discloses a stack assembly tool and assembly method for solving the problem of overpressure in the middle of the core caused by uneven thickness of the end plate. Chinese Patent Application Publication No. CN117317332A provides a fuel cell stack assembly method and device. The stack assembly method detects the stacking process of a single cell through image recognition technology, thereby realizing the automated operation of the fuel cell stack assembly. However, single-station stacking does not consider the impact of component processing quality and stacking order on assembly quality, which easily leads to poor consistency of the stack.

[0005] Chinese patent application publication number CN112836391A proposes a model-driven fuel cell stack assembly method. The method collects stack component parameters, evaluates and hierarchically stores the processing quality of stack components, plans the assembly sequence of stack components, modularizes the stack components, collects stack module parameters, evaluates and hierarchically stores the assembly quality of stack modules, plans the assembly sequence of stack modules, and assembles the stack as a whole. The group assembly takes into account the processing error and stacking sequence of the plates to meet the high-quality assembly requirements. However, the group assembly method requires measurement, grading, storage, and transportation, which complicates the assembly process and affects the assembly efficiency.

[0006] Therefore, for hydrogen fuel cell assembly, how to establish a more sophisticated stacking mode to meet the high-quality and high-efficiency assembly requirements of fuel cell stacks is an urgent problem to be solved. Summary of the invention

[0007] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a hydrogen fuel cell stack assembly method and system based on edge geometry feature accuracy constraints, so as to solve or partially solve the problems that the stacking accuracy is difficult to control during the component stacking process of hydrogen fuel cell assembly, affecting the assembly efficiency and product quality.

[0008] The purpose of the present invention can be achieved by the following technical solutions:

[0009] One aspect of the present invention provides a hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints, comprising the following steps:

[0010] Step S1, obtaining component information of a fuel cell stack, controlling a pressurizing device according to the component information, and stacking each component of the fuel cell stack layer by layer;

[0011] Step S2, in the layer-by-layer stacking process, in response to the completion of the stacking and pressing of the bipolar plates, by scanning the edge of the stacked battery stack, calculating the size deviation of the edge of the stacked battery stack;

[0012] Step S3, based on the edge size deviation of the stacked battery stack, by constructing a battery stack component deviation transfer model, predicting the deviation distribution interval of the components to be stacked;

[0013] Step S4, based on the predicted deviation distribution interval of subsequent stacking, determine whether the deviation distribution interval of the stack assembly to be stacked is within the preset stack deviation limit tolerance interval, if so, continue stacking and execute step S2, if not, stop stacking and execute step S5;

[0014] Step S5, ending the stacking of the current fuel cell stack and storing the parameters of the stacked fuel cell stack.

[0015] As a preferred technical solution, it also includes:

[0016] Step S6, repeating steps S1-S5 to obtain multiple fuel cell modules that meet the assembly accuracy requirements.

[0017] As a preferred technical solution, in the step S1, in response to the completion of one or more layers of battery stacking, the pressurizing device is controlled to apply pressure to the fuel cell stack.

[0018] As a preferred technical solution, in step S2, the process of calculating the edge size deviation of the stacked battery stack includes the following steps:

[0019] Step S201, acquiring position data of each layer of fuel cell stack components along a direction parallel to the stacking direction of the fuel cell stack;

[0020] Step S202, based on the position data of each layer of the battery stack assembly, calculate the deviation of each measurement point relative to the reference position to obtain the battery stack edge size deviation.

[0021] As a preferred technical solution, in step S3, the process of predicting the deviation distribution interval of subsequent stacking by constructing a deviation transfer model of the battery stack assembly includes the following steps:

[0022] Step S301, establishing a deviation transfer model of a single component of the battery stack according to the size error and assembly error of the single component of the battery stack, and obtaining the error distribution of the single component of the battery stack;

[0023] Step S302, predicting the size deviation of the next stacking layer through regression analysis based on the edge size deviation of the stacked battery stack;

[0024] Step S303: predicting the deviation distribution interval of subsequent components to be stacked based on the error distribution and the size deviation.

[0025] As a preferred technical solution, the deviation distribution interval of the subsequent components to be stacked is calculated based on the following formula:

[0026]

[0027] in, is the subsequent i-th layer component size deviation distribution, is the dimensional deviation of the stacked components, is the size error of the subsequent i-th layer component, is the assembly error of the subsequent i-th layer component, is the error term, and α, β, and γ are regression coefficients.

[0028] Another aspect of the present invention provides a hydrogen fuel cell stack assembly system based on edge geometric feature accuracy constraints, which is used to implement the aforementioned hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints, and the system includes:

[0029] Fuel stack assembly platform;

[0030] A press, cooperating with the stack assembly platform to pressurize the hydrogen fuel cell stack;

[0031] The optical detection device is arranged on at least one side of the hydrogen fuel cell stack and is used to collect the edge size deviation information of the stacked stack.

[0032] As a preferred technical solution, the hydrogen fuel cell stack comprises:

[0033] A positioning workbench connected to the press, wherein a bipolar plate, a sealing rubber and a membrane electrode assembly are arranged on the positioning workbench, wherein the sealing rubber is connected to the bipolar plate and the membrane electrode assembly respectively;

[0034] A positioning rod extends through the press.

[0035] As a preferred technical solution, the press comprises:

[0036] Press plate;

[0037] A screw rod, through which the pressing plate is connected to the stack assembly platform;

[0038] The guide rod is arranged along the pressing direction of the press.

[0039] As a preferred technical solution, it also includes:

[0040] A computer is connected to the optical detection device.

[0041] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0042] (1) Ensuring the assembly accuracy of hydrogen fuel cells: The present invention detects the deviation of the stacked bipolar plates during the assembly process, comprehensively considers the size error of the single component, the assembly error and the size deviation of the edge of the stacked battery, and predicts the error distribution of the components to be stacked to guide continued stacking or seeding stacking, thereby ensuring that the assembly deviation of the battery stack module is within the required range of assembly accuracy and that the quality of the battery stack module meets the requirements.

[0043] (2) High assembly flexibility: The present invention determines whether the stack meets the preset assembly accuracy requirements by considering whether the predicted value of the stack deviation distribution exceeds the assembly accuracy requirements, and dynamically determines the number of stack layers based on the dimensional characteristics of the bipolar plates, thereby improving the flexibility of the stack assembly process.

[0044] (3) High production efficiency: The present invention reduces the need for rework or readjustment due to unqualified stacking in a single stacking station by modularizing the stack. The stacked modules are easy to stack, carry and fix, which can effectively save storage space. Setting up multiple stacking stations on the production line can achieve continuous production with a high production cycle, and can well adapt to the mass production and high-quality production requirements of fuel cell stacks. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a flow chart of a hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints in an embodiment;

[0046] Figure 2 It is a structural diagram of a hydrogen fuel cell stack assembly system based on edge geometric feature accuracy constraints in an embodiment;

[0047] Figure 3 A schematic diagram of the three-dimensional structure of a battery stack in an embodiment;

[0048] Figure 4 is a schematic diagram of the measurement plane projection of the assembly accuracy requirement in the embodiment;

[0049] Figure 5 It is a schematic diagram of the measurement plane projection of the stack deviation distribution in the embodiment;

[0050] Figure 6 Schematic diagram of the measurement plane projection of the modular sub-stack of the battery stack in the embodiment,

[0051] Among them, 1. Stack assembly platform; 2. Hydrogen fuel cell stack; 201. Positioning workbench; 202. Positioning rod; 203. Sealing rubber; 204. Membrane electrode assembly; 205. Stacked bipolar plates; 206. Bipolar plates to be stacked; 3. Optical detection equipment; 4. Computer; 5. Press; 501. Press plate; 502. Screw; 503. Guide rod. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0053] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present invention. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0054] Example 1

[0055] In view of the problems existing in the above-mentioned prior art, in order to establish a more sophisticated stacking mode and meet the high-quality and high-efficiency assembly requirements of the fuel cell stack, this embodiment provides a hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints, see Figure 1 ,include:

[0056] Step S1, assembling hydrogen fuel cell components: Obtain the serial number information, geometric dimension information, process information and other parameters of the components of the fuel cell stack, such as the bipolar plate 206, the sealing rubber 203, the membrane electrode assembly 204, and the end plate. Stack the bipolar plate 206, the sealing rubber 203, and the membrane electrode 204 layer by layer. The press 5 applies a reasonable pressure to ensure that each component is fully pressed and avoid damage due to overload.

[0057] Step S2, collecting stack edge size deviation parameters: after each layer of bipolar plates 206 is stacked and pressed, scan the edge of the stacked stack 2 to calculate the stack edge size deviation.

[0058] Preferably, the process of collecting the stack size deviation parameter mainly includes steps S201-S202:

[0059] Step S201, scanning the edge of the stacked battery: calibrate the optical detection device 3. The optical detection device 3 performs real-time scanning along the edge of the stacked battery 2 to obtain the position data of the battery stack components. The battery stack edge refers to the edge of the battery stack parallel to the stacking direction.

[0060] Step S202, calculating the edge deviation of the stacked battery stack: based on the measured position data of each layer of battery stack components, calculating the deviation of each measuring point relative to the reference position to obtain the edge size deviation of the stacked battery stack.

[0061] Step S3, predicting the deviation distribution of the stack: establishing a deviation transfer model for the stack components. After stacking the second layer of bipolar plates, analyzing the deviation data of the stacked stack edge dimensions, and predicting the deviation distribution interval ε of the subsequent stacking based on the stacked data.

[0062] Preferably, during the assembly of hydrogen fuel cell components, the press may apply pressure after each layer of single cells are stacked, or may apply pressure after multiple layers of single cells are stacked, depending on the assembly conditions.

[0063] Preferably, see Figure 4 , predicting the stack deviation distribution mainly includes the following steps:

[0064] Step S301, establishing a deviation model for a single component of a fuel cell stack: considering the size error and assembly error of a single component of a fuel cell stack, establishing a deviation transfer model for a single component of a fuel cell stack, and establishing the deviation distribution of a single component of a fuel cell stack.

[0065] Step S302, analyzing the edge dimension deviation data of the stacked battery: After stacking the second layer of bipolar plates, analyze the edge straightness and dimension deviation direction of the stacked battery according to the edge dimension deviation data of the battery collected in S2. Through regression analysis, establish a dimension deviation model for the subsequent h-layer component stacking, and predict the dimension deviation of the subsequent h-layer component stacking.

[0066] Step S303, predict the deviation distribution of subsequent stacking based on the stacked data: the deviation of each layer is the result of the component deviation of the previous layer plus the size error and assembly error of the current component. Considering the size deviation, size error and assembly error of the stacked components in S301 and S302, a size deviation distribution model of the subsequent h-layer components is established, and the deviation distribution interval ε of the subsequent h-layer components is predicted.

[0067] The next level component size deviation distribution model can be established according to the following formula:

[0068]

[0069] Where: is the subsequent i-th layer component size deviation distribution, is the dimensional deviation of the stacked components, is the size error of the subsequent i-th layer component, is the assembly error of the subsequent i-th layer component, is the error term, and α, β, and γ are regression coefficients.

[0070] Step S4, modularization of the stack: determine whether the stack component deviation distribution interval ε exceeds the stack deviation limit tolerance interval δ, which is the stack assembly accuracy requirement. If the stack component deviation distribution interval ε does not exceed the stack deviation limit tolerance interval δ, continue stacking; if the stack component deviation distribution interval ε exceeds the stack deviation limit tolerance interval δ, stop stacking, and the stacked components form an independent stack module.

[0071] Preferably, see Figure 5 and Figure 6 The modularization of the fuel cell stack mainly includes the following steps:

[0072] Step S401, determine whether the stack component deviation distribution interval ε exceeds the stack deviation limit tolerance interval δ, the stack deviation limit tolerance interval is the stack assembly accuracy requirement. If the stack component deviation distribution interval ε does not exceed the stack deviation limit tolerance interval δ, continue to stack the next layer of components.

[0073] Step S402: If the stack component deviation distribution interval ε reaches or exceeds the stack deviation limit tolerance interval δ, the stacking operation is stopped.

[0074] Step S403: if step S402 is executed, the current stacked part is separated to form an independent stack module. The number of layers of each independent stack module is dynamically determined by the stack deviation to ensure that each independent stack module meets the assembly accuracy requirements.

[0075] Step S5, storing the single stack module and its parameters: storing the actual stack module in a storage location, and storing the corresponding stack module related parameters such as the number of single cells, stack edge size deviation, etc. in a database of the computer 4.

[0076] Step S6, stacking multiple battery stack modules: after physically storing the battery stack modules in the storage location, continue stacking from new components, repeat the inspection and stacking process until multiple battery stack modules that meet the assembly accuracy requirements are formed.

[0077] Preferably, the stacking of multiple battery stack modules in step S6 can be completed at a single workstation, or multiple workstations can be set up to assemble the battery stack modules simultaneously.

[0078] Example 2

[0079] Based on Example 1, this embodiment provides a hydrogen fuel cell stack assembly system based on edge geometric feature accuracy constraints, characterized in that it is used to implement the aforementioned hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints, see Figure 2 and Figure 3 , the system includes:

[0080] (1) Fuel cell assembly platform 1.

[0081] (2) a press machine 5, which cooperates with the stack assembly platform to pressurize the hydrogen fuel cell stack;

[0082] Preferably, the hydrogen fuel cell stack includes a positioning workbench connected to a press, a positioning rod penetrating the press, a membrane electrode assembly located on the positioning workbench, and a sealing rubber connected to the membrane electrode assembly.

[0083] Preferably, the press comprises: a press plate and a guide rod arranged along the pressing direction of the press, and the press plate is connected to the stack assembly platform via a screw rod.

[0084] (3) An optical detection device, disposed on at least one side of the hydrogen fuel cell stack, for collecting information on edge size deviations of the stacked stack.

[0085] (4) A computer connected to the optical detection equipment.

[0086] In summary, the hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraint provided by the present invention has at least the following beneficial effects compared with the prior art:

[0087] (1) By assembling fuel cell components, collecting stack size deviation parameters, predicting stack deviation distribution, and modularizing the stack, the assembly deviation of the stack module is ensured to be within the assembly accuracy requirements and the quality of the stack module meets the requirements.

[0088] (2) By considering whether the predicted value of the stack deviation distribution exceeds the assembly accuracy requirement range, it is determined whether the stack meets the preset assembly accuracy requirements. The number of stack layers is dynamically determined according to the size characteristics of the bipolar plates to improve the flexibility of the stack assembly process.

[0089] (3) The modular stacking method reduces the need for rework or readjustment due to unqualified stacking in a single stacking station. The stacked modules are easy to stack, carry and fix, which can effectively save storage space. Setting up multiple stacking stations on the production line can achieve continuous production and can well adapt to the mass production and high-quality production requirements of fuel cell stacks.

[0090] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints, characterized in that: The steps include: Step S1, obtaining component information of a fuel cell stack, controlling a pressurizing device according to the component information, and stacking each component of the fuel cell stack layer by layer; Step S2, in the layer-by-layer stacking process, in response to the completion of the stacking and pressing of the bipolar plates, by scanning the edge of the stacked battery stack, calculating the size deviation of the edge of the stacked battery stack; Step S3, based on the edge size deviation of the stacked battery, by constructing a battery stack component deviation transfer model, predicting the deviation distribution interval of subsequent components to be stacked; Step S4, based on the predicted deviation distribution interval of subsequent stacking, determine whether the deviation distribution interval of the stack assembly to be stacked is within the preset stack deviation limit tolerance interval, if so, continue stacking and execute step S2, if not, stop stacking and execute step S5; Step S5, ending the stacking of the current fuel cell stack and storing the parameters of the stacked fuel cell stack.

2. A hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints according to claim 1, characterized in that: Also includes: Step S6, repeating steps S1-S5 to obtain multiple fuel cell modules that meet the assembly accuracy requirements.

3. A hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints according to claim 1, characterized in that: In the step S1, in response to the completion of stacking of one or more layers of cells, the pressurizing device is controlled to apply pressure to the fuel cell stack.

4. A hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints according to claim 1, characterized in that: In step S2, the process of calculating the edge size deviation of the stacked battery stack includes the following steps: Step S201, acquiring position data of each layer of fuel cell stack components along a direction parallel to the stacking direction of the fuel cell stack; Step S202, based on the position data of each layer of the battery stack assembly, calculate the deviation of each measurement point relative to the reference position to obtain the battery stack edge size deviation.

5. The method for assembling a hydrogen fuel cell stack based on edge geometric feature accuracy constraints according to claim 1, characterized in that: In step S3, the process of predicting the deviation distribution interval of subsequent stacking by constructing a stack component deviation transfer model includes the following steps: Step S301, establishing a deviation transfer model of a single component of the battery stack according to the size error and assembly error of the single component of the battery stack, and obtaining the error distribution of the single component of the battery stack; Step S302, predicting the size deviation of the next stacking layer through regression analysis based on the edge size deviation of the stacked battery stack; Step S303: predicting the deviation distribution interval of subsequent components to be stacked based on the error distribution and the size deviation.

6. A hydrogen fuel cell stack assembly method based on edge geometric feature accuracy constraints according to claim 5, characterized in that: The deviation distribution interval of the subsequent components to be stacked is calculated based on the following formula: in, is the size deviation distribution of the subsequent i-th layer components, is the dimensional deviation of the stacked components, is the size error of the subsequent i-th layer component, is the assembly error of the subsequent i-th layer component, is the error term, and α, β, and γ are regression coefficients.

7. A hydrogen fuel cell stack assembly system based on edge geometric feature accuracy constraints, characterized in that: A method for assembling a hydrogen fuel cell stack based on edge geometric feature accuracy constraints as described in any one of claims 1 to 6, the system comprising: Fuel stack assembly platform (1); A press machine (5) cooperates with the stack assembly platform (1) to pressurize the hydrogen fuel cell stack (2); An optical detection device (3) is arranged on at least one side of the hydrogen fuel cell stack (2) and is used to collect edge size deviation information of the stacked stack.

8. A hydrogen fuel cell stack assembly system based on edge geometric feature precision constraints according to claim 7, characterized in that: The hydrogen fuel cell stack (2) comprises: A positioning workbench (201) connected to the press (5), wherein a bipolar plate (206), a sealing rubber (203) and a membrane electrode assembly (204) are arranged on the positioning workbench (201), wherein the sealing rubber (203) is connected to the bipolar plate (206) and the membrane electrode assembly (204) respectively; A positioning rod (202) passes through the press (5).

9. A hydrogen fuel cell stack assembly system based on edge geometric feature accuracy constraints according to claim 7, characterized in that: The press (5) comprises: Pressing plate (501); A screw rod (502), wherein the pressing plate (501) is connected to the stack assembly platform (1) via the screw rod (502); The guide rod (503) is arranged along the pressing direction of the press (5).

10. A hydrogen fuel cell stack assembly system based on edge geometric feature precision constraints according to claim 7, characterized in that: Also includes: A computer (4) is connected to the optical detection device (3).

Images