Battery stack assembly method, device, equipment and storage medium

Abstract

This invention belongs to the field of battery technology and discloses a battery stack assembly method, apparatus, equipment, and storage medium. The method includes: determining the current fastening force of each fastener in the battery stack based on the pre-assembly height and thickness compression ratio of the battery stack; constructing a three-dimensional digital twin model based on the fastener assembly strategy and the parameters of the battery stack, and calculating the springback displacement of each fastener based on the current fastening force; adjusting the fastening force of the fasteners based on the springback displacement until the springback displacement of the fasteners meets a preset condition to obtain a reference fastening force; and assembling the battery stack based on the reference fastening force. This invention calculates the springback displacement of the fasteners during the stack assembly process using a three-dimensional digital twin model and adjusts the fastening force at positions with different stiffnesses based on the springback displacement. This effectively ensures that the deformation at all parts of the battery stack is the same, avoiding battery component instability or even damage due to inconsistent compression at different positions, thus preventing battery stack leakage problems.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a battery stack assembly method, apparatus, equipment, and storage medium. Background Technology

[0002] A flow battery consists of a stack unit, electrolyte, electrolyte storage and supply unit, and management and control unit. Flow batteries are high-performance batteries that utilize separate positive and negative electrolytes for independent circulation. They are characterized by high capacity, wide range of applications (environments), and long cycle life.

[0003] The flow battery stack, as the main structure of the battery, is composed of one or more individual cells stacked together. During stacking, the flow battery stack needs to be pressurized and secured. Currently, pressurization and securing primarily target the pressing force. This method involves assembling the battery stack using an upper and lower end plate, fasteners, and a press. However, the assembly process fails to consider the stiffness differences of different fasteners, leading to significant springback displacement differences. This further results in inconsistent compression at different locations, inducing component instability or even breakage, and causing flow battery leakage.

[0004] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of this invention is to provide a battery stack assembly method that aims to solve the technical problem in the prior art where the uneven stiffness of the battery stack at different locations leads to inconsistent compression at different locations, which in turn induces component instability and damage, ultimately resulting in battery stack leakage.

[0006] To achieve the above objectives, the present invention provides a battery stack assembly method, the method comprising the following steps:

[0007] The current fastening force of each fastener of the battery stack is determined based on the pre-installed height and thickness compression ratio of the battery stack. The fastener is used to fix the clamps at the upper and lower ends of the battery stack.

[0008] A three-dimensional digital twin model is constructed based on the fastener assembly strategy and the parameters of the battery stack. The springback displacement of each fastener is obtained through the three-dimensional digital twin model based on the current fastening force.

[0009] In the three-dimensional digital twin model, the fastening force of the fastener is adjusted according to the springback displacement until the springback displacement of the fastener meets the preset conditions, and the reference fastening force of the fastener is obtained.

[0010] The battery stack is assembled according to the reference fastening force.

[0011] Optionally, determining the current fastening force of each fastener in the battery stack based on the pre-installed height and thickness compression ratio of the battery stack includes:

[0012] Obtain the electrochemical performance index requirements of the battery stack, and calculate the thickness compression ratio of the battery stack based on the pre-installed height of the battery stack according to the electrochemical performance index requirements.

[0013] The pressure on the upper end plate of the battery stack is calculated based on the thickness compression ratio and the pre-installation height.

[0014] The number of fasteners and their arrangement in the battery stack are obtained, and the current fastening force of each fastener in the battery stack is calculated based on the number of fasteners and their arrangement.

[0015] Optionally, the parameters of the battery stack include: material parameters, structural parameters, contact state parameters, and assembly parameters;

[0016] The step of constructing a three-dimensional digital twin model based on the fastener assembly strategy and the parameters of the battery stack, and obtaining the springback displacement of each fastener based on the current fastening force through the three-dimensional digital twin model, includes:

[0017] Obtain the material parameters, structural parameters, contact state parameters, and assembly parameters of the battery stack;

[0018] The mesh type and simulation parameters of the twin digital model are obtained by adjusting the mesh type of the digital model according to the material parameters, structural parameters, contact state parameters, and assembly parameters.

[0019] A three-dimensional digital twin model is constructed based on the mesh type, the simulation parameters, and the fastener assembly strategy;

[0020] The springback displacement of each fastener is obtained based on the current fastening force using the three-dimensional digital twin model.

[0021] Optionally, obtaining the springback displacement of each fastener based on the current fastening force through the three-dimensional digital twin model includes:

[0022] Obtain the thread pitch diameter and effective length of each fastener, and calculate the stiffness of each fastener based on the thread pitch diameter and the effective length.

[0023] The springback displacement of each fastener is calculated based on the fastening force and the stiffness.

[0024] Optionally, adjusting the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets a preset condition to obtain a reference fastening force for the fastener includes:

[0025] After fixing the fasteners in the three-dimensional digital twin model according to the current fastening force, the springback displacement of all fasteners is obtained, and it is determined whether there is a springback displacement greater than or equal to the springback displacement threshold among all the springback displacements of the fasteners.

[0026] If it does not exist, the current fastening force will be used as the reference fastening force;

[0027] If present, the fastening force of the fastener is adjusted according to the springback displacement.

[0028] Optionally, adjusting the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets a preset condition to obtain a reference fastening force of the fastener further includes:

[0029] After fixing the fasteners in the three-dimensional digital twin model according to the current fastening force, obtain the maximum and minimum springback displacements among all the springback displacements of the fasteners.

[0030] The difference in rebound displacement is obtained based on the maximum rebound displacement and the minimum rebound displacement.

[0031] Determine whether the difference in rebound displacement is greater than or equal to a difference threshold;

[0032] If the difference in rebound displacement is less than the difference threshold, then the current fastening force is used as the reference fastening force.

[0033] If the difference in springback displacement is greater than or equal to the difference threshold, the fastening force of the fastener is adjusted according to the springback displacement.

[0034] Optionally, adjusting the fastening force of the fastener according to the springback displacement includes:

[0035] Obtain the preset deformation of each fastener;

[0036] The intermediate fastening force is obtained based on the preset deformation, the current fastening force, and the springback deformation of each fastener;

[0037] The intermediate springback displacement of each fastener is calculated based on the intermediate fastening force using the three-dimensional digital twin model.

[0038] If the intermediate springback displacement of all fasteners meets the preset conditions, and if the preset conditions are not met, the intermediate fastening force is obtained by repeating the steps of obtaining the intermediate fastening force based on the preset deformation, the current fastening force, and the springback deformation of each fastener; and the intermediate springback displacement of each fastener is calculated based on the intermediate fastening force through the three-dimensional digital twin model, thereby adjusting the fastening force of the fasteners.

[0039] Furthermore, to achieve the above objectives, the present invention also proposes a battery stack assembly apparatus, the battery stack assembly apparatus comprising:

[0040] The parameter acquisition module is used to determine the current fastening force of each fastener of the battery stack based on the pre-installed height and thickness compression ratio of the battery stack.

[0041] The model building module is used to build a three-dimensional digital twin model based on the fastener assembly strategy and the parameters of the battery stack, and to obtain the springback displacement of each fastener based on the current fastening force through the three-dimensional digital twin model.

[0042] The fastening force calculation module is used to adjust the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets the preset conditions, so as to obtain the reference fastening force of the fastener.

[0043] A battery stack assembly module is used to assemble the battery stack according to the reference fastening force.

[0044] Furthermore, to achieve the above objectives, the present invention also proposes a battery stack assembly apparatus, the battery stack assembly apparatus comprising: a memory, a processor, and a battery stack assembly program stored in the memory and executable on the processor, the battery stack assembly program being configured to implement the steps of the battery stack assembly method as described above.

[0045] In addition, to achieve the above objectives, the present invention also proposes a storage medium storing a battery stack assembly program, wherein when the battery stack assembly program is executed by a processor, the steps of the battery stack assembly method as described above are implemented.

[0046] This invention uses a three-dimensional digital twin model to simulate the springback displacement that may occur during the assembly of the battery stack by the fastening force of the fasteners. Based on the springback displacement, the fastening force at positions with different stiffness is continuously adjusted until the stiffness deformation at each position of the battery stack is the same. This can effectively ensure that the deformation at all parts of the battery stack is the same, and avoid battery component instability or even damage caused by inconsistent compression at different positions, thus preventing battery stack leakage problems. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the structure of the battery stack assembly equipment in the hardware operating environment involved in the embodiments of the present invention;

[0048] Figure 2 This is a flowchart illustrating the first embodiment of the battery stack assembly method of the present invention;

[0049] Figure 3 This is a schematic diagram of a battery stack assembly according to an embodiment of the battery stack assembly method of the present invention;

[0050] Figure 4 This is a schematic diagram showing the number and arrangement of fasteners in an embodiment of the battery stack assembly method of the present invention;

[0051] Figure 5 This is a flowchart illustrating the second embodiment of the battery stack assembly method of the present invention;

[0052] Figure 6 This is a schematic diagram of the fastening force adjustment process in an embodiment of the battery stack assembly method of the present invention;

[0053] Figure 7 This is a structural block diagram of the first embodiment of the battery stack assembly device of the present invention.

[0054] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0055] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0056] Reference Figure 1 , Figure 1 This is a schematic diagram of the battery stack assembly equipment structure for the hardware operating environment involved in the embodiments of the present invention.

[0057] like Figure 1 As shown, the battery stack assembly equipment may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. The memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001.

[0058] Those skilled in the art will understand that Figure 1The structure shown does not constitute a limitation on the battery stack assembly equipment and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0059] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a battery stack assembly program.

[0060] exist Figure 1 In the battery stack assembly equipment shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the battery stack assembly equipment of the present invention can be set in the battery stack assembly equipment, and the battery stack assembly equipment calls the battery stack assembly program stored in the memory 1005 through the processor 1001 and executes the battery stack assembly method provided in the embodiment of the present invention.

[0061] This invention provides a battery stack assembly method, referring to... Figure 2 , Figure 2 This is a schematic flowchart of a first embodiment of a battery stack assembly method according to the present invention.

[0062] In this embodiment, the battery stack assembly method includes the following steps:

[0063] Step S10: Determine the current fastening force of each fastener of the battery stack according to the pre-installed height and thickness compression ratio of the battery stack. The fastener is used to fix the clamps at the upper and lower ends of the battery stack.

[0064] Understandably, the pre-installed height of the battery stack can be a pre-set height after multiple individual cells are stacked and fixed with fasteners.

[0065] It is understood that the battery stack in this embodiment is a flow battery. A flow battery consists of a stack unit, an electrolyte, an electrolyte storage and supply unit, and a management and control unit. Excessive pressure cannot be applied during the stack assembly process to compress it, otherwise it may cause damage and rupture of the battery stack.

[0066] It should be noted that the fasteners are used to secure the clamps at both ends of the battery stack; for details, please refer to [reference needed]. Figure 3 The diagram shows the battery stack placed between two perforated clamps, which are then secured with fasteners to assemble the battery stack. The positions of the holes on the clamps correspond to each other. This embodiment does not limit the number of holes on the clamps and can be adjusted according to actual conditions.

[0067] It should be further explained that determining the current fastening force of each fastener of the battery stack based on the pre-installed height and thickness compression ratio of the battery stack can be achieved by obtaining the electrochemical performance index requirements of the battery stack (the electrochemical performance index of the battery stack may include voltage, capacity, specific energy, specific power, etc.).

[0068] The thickness compression ratio of the battery stack is calculated based on the electrochemical performance requirements and the pre-installation height of the battery stack. The upper plate pressure of the battery stack is calculated based on the thickness compression ratio and the pre-installation height (the battery stack is stacked on the lower plate, and the upper plate of the battery stack is compressed by applying pressure downward through a press. The press compresses the battery stack according to the thickness compression ratio until the height of the battery stack reaches the pre-installation height. The pressure applied by the press at this time is the upper plate pressure).

[0069] The quantity and arrangement of fasteners in the battery stack are obtained (this can be done directly from a pre-set quantity and arrangement, or by acquiring an image of the top plate of the battery stack and identifying the fasteners based on that image; specific arrangements and fastener quantities can be found in [reference needed]). Figure 4 In the diagram, the rectangles represent the upper and lower end plates, and the black dots can be interpreted as the locations for fastener installation. The gaps left in the middle of the arrangement of the black dots represent the arrangement of the battery stack.

[0070] Calculate the current fastening force of each fastener in the battery stack based on the number and arrangement of the fasteners. (It should be noted that developing a fastener assembly plan includes determining the number and arrangement of fasteners, selecting fastener types, and calculating the initial fastening force applied to each fastener; in specific implementation, refer to...) Figure 4 The number of fasteners is 12, and the fasteners are arranged as follows: Figure 4 If the pressure applied to the upper end plate of the battery stack is P, then the current fastening force is P / 12.

[0071] It should be noted that the fastener arrangement can be... Figure 4 The equidistant arrangement is shown. When the number of fasteners is not less than 5, they can also be arranged from the middle fastener outwards with increasing or decreasing edge spacing.

[0072] It should be emphasized that the fastener can be a threaded connection component or a rope connection component. If the fastener is a threaded connection component, then the stiffness K = πd²E / 4l, where d is the thread pitch diameter, E is the Young's modulus of the material, and l is the effective length of the fastener (the distance between the two nearest locking nuts).

[0073] Step S20: Construct a three-dimensional digital twin model based on the fastener assembly strategy and the parameters of the battery stack, and obtain the springback displacement of each fastener based on the current fastening force through the three-dimensional digital twin model.

[0074] It should be noted that the parameters of the battery stack can include the material parameters, structural parameters, contact state parameters, and assembly parameters of the stack; among which, the material parameters can include Young's modulus and Poisson's ratio, the structural parameters can be the dimensions of the parts, the coefficient of friction between the contact surfaces of all parts, and the assembly parameters can be the compression displacement of the press.

[0075] Understandably, a three-dimensional digital twin model is constructed based on the parameters of the battery stack and the fastener assembly strategy. The three-dimensional digital twin model can simulate the assembly of the battery stack under the parameters of the battery stack, collect the problems and errors that occur during the assembly process, and adjust the parameters through the three-dimensional digital twin model to obtain the final adjusted parameters. The parameters are then applied to the actual assembly of the battery stack, avoiding repeated assembly failures caused by direct assembly, which would lead to resource waste.

[0076] It should be noted that a three-dimensional digital twin model is constructed based on the fastener assembly strategy and the parameters of the battery stack. The springback displacement of each fastener obtained through the three-dimensional digital twin model based on the current fastening force can be obtained by acquiring the material parameters, structural parameters, contact state parameters, and assembly parameters of the battery stack. The mesh type of the digital model is adjusted according to the material parameters, structural parameters, contact state parameters, and assembly parameters to obtain the mesh type and simulation parameters of the twin digital model. It is understood that the initial three-dimensional digital twin model is only a framework. The parameters in the initial model need to be adjusted according to the material parameters, structural parameters, contact state parameters, and assembly parameters so that the digital twin model can more closely resemble the actual battery stack situation, thereby more accurately simulating and discovering potential problems in the battery stack assembly process.

[0077] A three-dimensional digital twin model is constructed based on the mesh type, the simulation parameters, and the fastener assembly strategy. In specific implementation, by adjusting simulation technical parameters such as mesh type and size, a three-dimensional digital twin model of the fuel cell stack assembly process that matches the actual physical model is achieved. The assembly process includes three stages: press press down to the design displacement, fastener assembly, and press unloading.

[0078] Based on the current fastening force, the springback displacement of each fastener is obtained through the three-dimensional digital twin model. It can be understood that the upper and lower end plates of the battery stack are fixed based on the current fastening force. After the press is removed after being fixed by the fasteners, the springback displacement between the upper and lower end plates at each fastener is different because the stiffness of different fasteners is different.

[0079] It should be emphasized that the springback displacement of each fastener obtained through the three-dimensional digital twin model based on the current fastening force can be obtained by acquiring the thread pitch diameter and effective length of each fastener, obtaining the stiffness of each fastener based on the thread pitch diameter and the effective length, and calculating the springback displacement of each fastener based on the fastening force and the stiffness.

[0080] Step S30: Adjust the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets the preset conditions, and obtain the reference fastening force of the fastener.

[0081] Understandably, because different fasteners have different stiffness, their springback displacement is also different. The tightening force of each fastener is adjusted according to the springback displacement of each fastener until the springback displacement of each fastener is the same.

[0082] It should be understood that when the rebound displacement is the same, the fixed height of each position of the battery stack is the same. This avoids the problem of inconsistent compression at different positions due to uneven assembly height during the assembly process, which could induce battery component instability or even damage, thus leading to battery stack leakage.

[0083] Understandably, the reference fastening force can be the fastening force that corresponds to the springback displacement when it meets the requirements after adjustment.

[0084] Step S40: Assemble the battery stack according to the reference fastening force.

[0085] It is understandable that the assembly of the battery stack based on the reference fastening force is performed during the actual battery stack assembly process based on the reference fastening force obtained from the unit digital twin model.

[0086] This embodiment uses a three-dimensional digital twin model to simulate the springback displacement that may occur during the assembly of the battery stack. Based on the springback displacement, the fastening force at different stiffness positions is continuously adjusted until the stiffness deformation at each position of the battery stack is the same. This can effectively ensure that the deformation at all parts of the battery stack is the same, and avoid battery component instability or even damage caused by inconsistent compression at different positions, thus preventing battery stack leakage problems.

[0087] refer to Figure 5 , Figure 5 This is a schematic flowchart of a second embodiment of a battery stack assembly method according to the present invention.

[0088] Based on the first embodiment described above, the battery stack assembly method of this embodiment includes the following in step S30:

[0089] Step S301: After fixing the fasteners in the three-dimensional digital twin model according to the current fastening force, obtain the springback displacement of all fasteners and determine whether there is a springback displacement greater than or equal to the springback displacement threshold among all the springback displacements of the fasteners.

[0090] Understandably, all fasteners can be installed while the press is still applying pressure to the top plate of the battery stack, and after the press is removed, there will be springback displacement of the same or different amounts between the various fasteners of the battery stack.

[0091] It should be noted that determining whether there is a springback displacement greater than or equal to the springback displacement threshold among all fasteners can be done by collecting the springback displacement of all fasteners, comparing the springback displacement of each fastener with the springback displacement threshold, and then determining whether there are any fasteners with a springback displacement greater than or equal to the springback displacement threshold based on the comparison results.

[0092] Step S302: If it does not exist, then the current fastening force is used as the reference fastening force.

[0093] Understandably, if after comparing the springback displacement of each fastener with the springback displacement threshold, the springback displacement of all fasteners is less than the springback displacement threshold, then the current fastening force is used as the reference fastening force, and the reference fastening force can be used for assembly in actual battery stack assembly.

[0094] Step S303: If present, adjust the fastening force of the fastener according to the springback displacement.

[0095] It should be noted that adjusting the fastening force of the fastener according to the springback displacement can be achieved by obtaining a preset deformation of each fastener (or simply understood as a preset springback displacement).

[0096] The intermediate fastening force is obtained based on the preset deformation, the current fastening force, and the springback deformation of each fastener (the difference in deformation, i.e., the difference in springback displacement, is obtained based on the preset deformation and the current springback deformation, and the intermediate fastening force is calculated based on this difference and the current fastening force).

[0097] Based on the intermediate fastening force, the intermediate springback displacement of each fastener is calculated using the three-dimensional digital twin model (simulated in the three-dimensional digital twin model using the intermediate fastening force, pressure is applied to the upper end plate using a press, and the fastening force of each fastener is adjusted simultaneously).

[0098] If the intermediate springback displacement of all fasteners meets the preset conditions, and if the preset conditions are not met, the intermediate fastening force is obtained by repeating the steps of obtaining the intermediate fastening force based on the preset deformation, the current fastening force, and the springback deformation of each fastener; and the intermediate springback displacement of each fastener is calculated based on the intermediate fastening force through the three-dimensional digital twin model, thereby adjusting the fastening force of the fasteners.

[0099] It should be emphasized that the step of adjusting the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets the preset condition to obtain the reference fastening force of the fastener also includes:

[0100] After fixing the fasteners in the three-dimensional digital twin model according to the current fastening force, obtain the maximum and minimum springback displacements among all the springback displacements of the fasteners.

[0101] The difference in rebound displacement is obtained based on the maximum rebound displacement and the minimum rebound displacement; it is then determined whether the difference in rebound displacement is greater than or equal to a difference threshold.

[0102] If the difference in springback displacement is less than a threshold value, the current tightening force is used as a reference tightening force; if the difference in springback displacement is greater than or equal to the threshold value, the tightening force of the fastener is adjusted according to the springback displacement. (It should be noted that determining whether to adjust the tightening force can also involve comparing the maximum and minimum springback displacement of all fasteners. If the difference between the maximum and minimum springback displacement is less than the threshold value, no adjustment is made; if it is greater than or equal to the threshold value, adjustment is made. It is important to emphasize that the two tightening force adjustment criteria can be used to adjust the tightening force when one of the criteria is met, or when both criteria are met simultaneously.)

[0103] In specific implementation, you can refer to Figure 6 , Figure 6 It describes the process of adjusting the fastening force in a three-dimensional digital twin model, where the strength F represents the maximum force that the fastener can withstand, and N represents the springback displacement threshold.

[0104] This embodiment compares the springback displacement of all fasteners simulated in a three-dimensional digital twin model with the springback displacement threshold to determine whether the springback displacement meets the springback displacement threshold. If the preset conditions are met, adjustments are made. Through repeated adjustments, a reference preload for each fastener is obtained, while avoiding repeated adjustments due to only minor differences, which would reduce efficiency.

[0105] Furthermore, this embodiment of the invention also proposes a storage medium storing a battery stack assembly program, which, when executed by a processor, implements the steps of the battery stack assembly method described above.

[0106] Reference Figure 7 , Figure 7 This is a structural block diagram of the first embodiment of the battery stack assembly device of the present invention.

[0107] like Figure 7 As shown, the battery stack assembly device proposed in this embodiment of the invention includes:

[0108] The parameter acquisition module 10 is used to determine the current fastening force of each fastener of the battery stack based on the pre-installed height and thickness compression ratio of the battery stack.

[0109] The model building module 20 is used to build a three-dimensional digital twin model based on the fastener assembly strategy and the parameters of the battery stack, and to obtain the springback displacement of each fastener based on the current fastening force through the three-dimensional digital twin model.

[0110] The fastening force calculation module 30 is used to adjust the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets the preset conditions, so as to obtain the reference fastening force of the fastener.

[0111] The battery stack assembly module 40 is used to assemble the battery stack according to the reference fastening force.

[0112] This embodiment uses a three-dimensional digital twin model to simulate the springback displacement that may occur during the assembly of the battery stack. Based on the springback displacement, the fastening force at different stiffness positions is continuously adjusted until the stiffness deformation at each position of the battery stack is the same. This can effectively ensure that the deformation at all parts of the battery stack is the same, and avoid battery component instability or even damage caused by inconsistent compression at different positions, thus preventing battery stack leakage problems.

[0113] In one embodiment, the parameter acquisition module 10 is further configured to acquire the electrochemical performance index requirements of the battery stack, and calculate the thickness compression ratio of the battery stack based on the pre-installed height of the battery stack according to the electrochemical performance index requirements.

[0114] The pressure on the upper end plate of the battery stack is calculated based on the thickness compression ratio and the pre-installation height.

[0115] The number of fasteners and their arrangement in the battery stack are obtained, and the current fastening force of each fastener in the battery stack is calculated based on the number of fasteners and their arrangement.

[0116] In one embodiment, the model building module 20 is further used to obtain the material parameters, structural parameters, contact state parameters, and assembly parameters of the battery stack;

[0117] The mesh type and simulation parameters of the twin digital model are obtained by adjusting the mesh type of the digital model according to the material parameters, structural parameters, contact state parameters, and assembly parameters.

[0118] A three-dimensional digital twin model is constructed based on the mesh type, the simulation parameters, and the fastener assembly strategy;

[0119] The springback displacement of each fastener is obtained based on the current fastening force using the three-dimensional digital twin model.

[0120] In one embodiment, the model building module 20 is further configured to obtain the thread pitch diameter and effective length of each fastener, and to obtain the stiffness of each fastener based on the thread pitch diameter and the effective length.

[0121] The springback displacement of each fastener is calculated based on the fastening force and the stiffness.

[0122] In one embodiment, the fastening force calculation module 30 is further configured to obtain the springback displacement of all fasteners after fixing them in the three-dimensional digital twin model according to the current fastening force, and determine whether there is a springback displacement greater than or equal to the springback displacement threshold among all the springback displacements of the fasteners.

[0123] If it does not exist, the current fastening force will be used as the reference fastening force;

[0124] If present, the fastening force of the fastener is adjusted according to the springback displacement.

[0125] In one embodiment, the fastening force calculation module 30 is further used to obtain the maximum and minimum springback displacements among all fasteners after fixing them according to the current fastening force in the three-dimensional digital twin model.

[0126] The difference in rebound displacement is obtained based on the maximum rebound displacement and the minimum rebound displacement.

[0127] Determine whether the difference in rebound displacement is greater than or equal to a difference threshold;

[0128] If the difference in rebound displacement is less than the difference threshold, then the current fastening force is used as the reference fastening force.

[0129] If the difference in springback displacement is greater than or equal to the difference threshold, the fastening force of the fastener is adjusted according to the springback displacement.

[0130] In one embodiment, the fastening force calculation module 30 is further configured to obtain a preset deformation of each fastener;

[0131] The intermediate fastening force is obtained based on the preset deformation, the current fastening force, and the springback deformation of each fastener;

[0132] The intermediate springback displacement of each fastener is calculated based on the intermediate fastening force using the three-dimensional digital twin model.

[0133] If the intermediate springback displacement of all fasteners meets the preset conditions, and if the preset conditions are not met, the intermediate fastening force is obtained by repeating the steps of obtaining the intermediate fastening force based on the preset deformation, the current fastening force, and the springback deformation of each fastener; and the intermediate springback displacement of each fastener is calculated based on the intermediate fastening force through the three-dimensional digital twin model, thereby adjusting the fastening force of the fasteners.

[0134] It should be understood that the above are merely illustrative examples and do not constitute any limitation on the technical solutions of the present invention. In specific applications, those skilled in the art can make settings as needed, and the present invention does not impose any restrictions on this.

[0135] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this invention. In practical applications, those skilled in the art can select some or all of the workflow to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0136] Furthermore, it should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0137] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0138] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory (ROM) / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0139] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method of assembling a battery stack, characterized by, The battery stack assembly method includes: The current fastening force of each fastener of the battery stack is determined based on the pre-installed height and thickness compression ratio of the battery stack. The fastener is used to fix the clamps at the upper and lower ends of the battery stack. A three-dimensional digital twin model is constructed based on the fastener assembly strategy and the parameters of the battery stack. The springback displacement of each fastener is obtained through the three-dimensional digital twin model based on the current fastening force. In the three-dimensional digital twin model, the fastening force of the fastener is adjusted according to the springback displacement until the springback displacement of the fastener meets the preset conditions, and the reference fastening force of the fastener is obtained. The battery stack is assembled according to the reference fastening force; The determination of the current fastening force of each fastener in the battery stack based on the pre-installed height and thickness compression ratio of the battery stack includes: Obtain the electrochemical performance index requirements of the battery stack, and calculate the thickness compression ratio of the battery stack based on the pre-installed height of the battery stack according to the electrochemical performance index requirements. The pressure on the upper end plate of the battery stack is calculated based on the thickness compression ratio and the pre-installation height. The number of fasteners and the arrangement of the fasteners in the battery stack are obtained, and the current fastening force of each fastener in the battery stack is calculated based on the number of fasteners and the arrangement. The parameters of the battery stack include: material parameters, structural parameters, contact state parameters, and assembly parameters; The step of constructing a three-dimensional digital twin model based on the fastener assembly strategy and the parameters of the battery stack, and obtaining the springback displacement of each fastener based on the current fastening force through the three-dimensional digital twin model, includes: Obtain the material parameters, structural parameters, contact state parameters, and assembly parameters of the battery stack; The mesh type and simulation parameters of the twin digital model are obtained by adjusting the mesh type of the digital model according to the material parameters, structural parameters, contact state parameters, and assembly parameters. A three-dimensional digital twin model is constructed based on the mesh type, the simulation parameters, and the fastener assembly strategy; Based on the current fastening force, the springback displacement of each fastener is obtained through the three-dimensional digital twin model; The step of adjusting the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets the preset condition to obtain the reference fastening force of the fastener includes: After fixing the fasteners in the three-dimensional digital twin model according to the current fastening force, the springback displacement of all fasteners is obtained, and it is determined whether there is a springback displacement greater than or equal to the springback displacement threshold among all the springback displacements of the fasteners. If it does not exist, the current fastening force will be used as the reference fastening force; If present, the fastening force of the fastener is adjusted according to the springback displacement.

2. The battery stack assembly method as described in claim 1, characterized in that, The process of obtaining the springback displacement of each fastener based on the current fastening force using the three-dimensional digital twin model includes: Obtain the thread pitch diameter and effective length of each fastener, and calculate the stiffness of each fastener based on the thread pitch diameter and the effective length. The springback displacement of each fastener is calculated based on the fastening force and the stiffness.

3. The battery stack assembly method as described in claim 1, characterized in that, The step of adjusting the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets the preset condition to obtain the reference fastening force of the fastener also includes: After fixing the fasteners in the three-dimensional digital twin model according to the current fastening force, obtain the maximum and minimum springback displacements among all the springback displacements of the fasteners. The difference in rebound displacement is obtained based on the maximum rebound displacement and the minimum rebound displacement. Determine whether the difference in rebound displacement is greater than or equal to a difference threshold; If the difference in rebound displacement is less than the difference threshold, then the current fastening force is used as the reference fastening force. If the difference in springback displacement is greater than or equal to the difference threshold, the fastening force of the fastener is adjusted according to the springback displacement.

4. The battery stack assembly method according to any one of claims 1-3, characterized in that, The adjustment of the fastening force of the fastener based on the springback displacement includes: Obtain the preset deformation of each fastener; The intermediate fastening force is obtained based on the preset deformation, the current fastening force, and the springback deformation of each fastener; The intermediate springback displacement of each fastener is calculated based on the intermediate fastening force using the three-dimensional digital twin model. If the intermediate springback displacement of all fasteners meets the preset conditions, and if the preset conditions are not met, the intermediate fastening force is obtained by repeating the steps of obtaining the intermediate fastening force based on the preset deformation, the current fastening force, and the springback deformation of each fastener; and the intermediate springback displacement of each fastener is calculated based on the intermediate fastening force through the three-dimensional digital twin model, thereby adjusting the fastening force of the fasteners.

5. A battery stack assembly device, characterized in that, The battery stack assembly device includes: The parameter acquisition module is used to determine the current fastening force of each fastener of the battery stack based on the pre-installed height and thickness compression ratio of the battery stack. The model building module is used to build a three-dimensional digital twin model based on the fastener assembly strategy and the parameters of the battery stack, and to obtain the springback displacement of each fastener based on the current fastening force through the three-dimensional digital twin model. The fastening force calculation module is used to adjust the fastening force of the fastener in the three-dimensional digital twin model according to the springback displacement until the springback displacement of the fastener meets the preset conditions, so as to obtain the reference fastening force of the fastener. A battery stack assembly module is used to assemble the battery stack according to the reference fastening force; The parameter acquisition module is also used to acquire the electrochemical performance index requirements of the battery stack, and calculate the thickness compression ratio of the battery stack based on the pre-installed height of the battery stack according to the electrochemical performance index requirements. The pressure on the upper end plate of the battery stack is calculated based on the thickness compression ratio and the pre-installation height. The number of fasteners and the arrangement of the fasteners in the battery stack are obtained, and the current fastening force of each fastener in the battery stack is calculated based on the number of fasteners and the arrangement. The model building module is also used to obtain the material parameters, structural parameters, contact state parameters, and assembly parameters of the battery stack; The mesh type and simulation parameters of the twin digital model are obtained by adjusting the mesh type of the digital model according to the material parameters, structural parameters, contact state parameters, and assembly parameters. A three-dimensional digital twin model is constructed based on the mesh type, the simulation parameters, and the fastener assembly strategy; Based on the current fastening force, the springback displacement of each fastener is obtained through the three-dimensional digital twin model; The fastening force calculation module is also used to obtain the springback displacement of all fasteners after fixing them according to the current fastening force in the three-dimensional digital twin model, and to determine whether there is a springback displacement greater than or equal to the springback displacement threshold among all the springback displacements of the fasteners. If it does not exist, the current fastening force will be used as the reference fastening force; If present, the fastening force of the fastener is adjusted according to the springback displacement.

6. A battery stack assembly device, characterized in that, The device includes: a memory, a processor, and a battery stack assembly program stored in the memory and executable on the processor, the battery stack assembly program being configured to implement the battery stack assembly method as described in any one of claims 1 to 4.

7. A storage medium, characterized in that, The storage medium stores a battery stack assembly program, which, when executed by a processor, implements the battery stack assembly method as described in any one of claims 1 to 4.

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