A method and device for modeling and simulating a welding area of a battery pack case

Abstract

This specification discloses a modeling and simulation method and apparatus for the welded area of ​​a battery pack housing. The method includes importing a three-dimensional model of the battery pack into finite element preprocessing software and meshing the model; creating weld elements at the weld locations in the three-dimensional model, and extending adjacent heat-affected zone elements from the weld elements using an extension command; assigning a preset first plastic material curve to the base material elements, and assigning second plastic material curves to the weld elements and heat-affected zone elements; importing the three-dimensional model with the assigned plastic material curves into a finite element solver to obtain the equivalent plastic strain corresponding to the weld output by the solver, and generating simulation results based on the equivalent plastic strain. In this embodiment, the weakening of material strength in the welded area due to thermal cycling can be reflected separately, thereby avoiding overestimation of the housing structure's load-bearing capacity and achieving a more accurate simulation assessment of the failure risk of the welded area.

Description

Technical Field

[0001] The embodiments in this specification pertain to the field of battery simulation modeling, and specifically relate to a modeling and simulation method and apparatus for the welding area of ​​a battery pack casing. Background Technology

[0002] Existing battery pack simulation technologies typically suffer from two shortcomings when performing explicit analyses such as mechanical impact and simulated collisions. Firstly, the welded area is not separately geometrically refined and meshed during modeling; it is simply evaluated as a continuum with the base material, failing to reflect the stress concentration effects caused by abrupt geometric changes in the weld and heat-affected zone. Secondly, the welded area is typically weaker than the base material due to thermal cycling, but current simulations often assign the same material properties to the welded area as the base material, neglecting the degradation of material properties in the welded area, thus overestimating the structural strength of the battery pack. In summary, current methods usually only focus on the failure of the base material of the internal structural components, neglecting accurate assessment of the welded area, leading to significant discrepancies between simulation results and actual failure modes. Summary of the Invention

[0003] The embodiments of this disclosure provide a modeling and simulation method and apparatus for the welding area of ​​a battery pack housing, which aims to solve one or more of the above-mentioned problems and other potential problems.

[0004] According to a first aspect of this disclosure, a modeling and simulation method for the welding area of ​​a battery pack housing is provided. The method includes importing a three-dimensional model of the battery pack into finite element preprocessing software and meshing the three-dimensional model.

[0005] Create weld elements at the weld location in the 3D model, and extend adjacent heat-affected zone elements from the weld elements based on the extension command;

[0006] A preset first plastic material curve is assigned to the base material region unit, and a second plastic material curve is assigned to the weld unit and the heat-affected zone unit. The second plastic material curve is obtained by multiplying the stress value in the first plastic material curve by a reduction factor. The reduction factor is determined based on the ratio of the weld material strength to the base material strength.

[0007] The three-dimensional model with the plastic material curve is imported into the finite element solver to obtain the equivalent plastic strain of the weld output by the finite element solver. Simulation results are then generated based on the equivalent plastic strain to characterize whether there is a risk of weld failure.

[0008] According to a second aspect of this disclosure, a modeling and simulation device for the welding area of ​​a battery pack housing is provided. The device includes a mesh generation module, which is configured to import a three-dimensional model of the battery pack into finite element preprocessing software and perform mesh generation on the three-dimensional model.

[0009] The extension module is configured to create weld elements at the weld location in the 3D model, and extends adjacent heat-affected zone elements from the weld elements based on the extension command;

[0010] The curve setting module is configured to assign a preset first plastic material curve to the base material area unit and a second plastic material curve to the weld unit and heat-affected zone unit. The second plastic material curve is obtained by multiplying the stress value in the first plastic material curve by a reduction factor, which is determined based on the ratio of the weld material strength to the base material strength.

[0011] The simulation module is configured to import a 3D model with a plastic material curve into the finite element solver to obtain the equivalent plastic strain of the weld output by the finite element solver, and generate simulation results based on the equivalent plastic strain to characterize whether there is a risk of weld failure.

[0012] According to a third aspect of this disclosure, an electronic device is provided, including one or more processors and a memory associated with the one or more processors, the memory being used to store program instructions that, when read and executed by the one or more processors, perform a method provided according to a first scheme.

[0013] According to a fourth aspect of this disclosure, a computer program product is provided, including a computer program that, when executed by a processor, implements the method provided according to the first aspect.

[0014] The solution provided in the embodiments of this specification can separate and model the three regions of weld, heat-affected zone and base material through mesh generation and expansion selection in the preprocessing stage. This allows the mesh of the weld area to be independently represented. Combined with the second plastic material curve determined based on the first plastic material curve of the base material region unit, it can separately reflect the weakening of material strength in the weld area due to thermal cycling. This avoids overestimating the load-bearing capacity of the box structure and achieves a more accurate simulation assessment of the failure risk of the weld area. Attached Figure Description

[0015] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0016] Figure 1 A flowchart illustrating a modeling and simulation method for the welding area of ​​a battery pack housing according to some embodiments of this disclosure is shown.

[0017] Figure 2 A schematic diagram of the structure of a modeling and simulation apparatus for the welding area of ​​a battery pack housing, according to some embodiments of this disclosure, is shown.

[0018] Figure 3 A schematic block diagram of an electronic device according to some embodiments of the present disclosure is shown. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] The terms “comprising” and “having”, and any variations thereof, in this specification, claims, and the foregoing drawings are intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. Depending on the context, the word “if” as it applies herein may be interpreted as “when”, “in response to determination”, or “in response to detection”.

[0021] Figure 1 A flowchart illustrating a modeling and simulation method 100 for the welding area of ​​a battery pack casing, according to some embodiments of this disclosure, is shown. Method 100 can be executed by a terminal, which may include, but is not limited to, mobile phones, tablets, desktop computers, servers, etc. Figure 1 As shown, in method 100, step 102 can involve importing the three-dimensional model of the battery pack into the finite element preprocessing software and meshing the three-dimensional model.

[0022] In this embodiment, after constructing a 3D model by acquiring the mathematical model information of the battery pack to be simulated, the 3D model can be imported into finite element preprocessing software (such as HyperMesh) for mesh generation. The basic size of the overall mesh can be preset, for example, to 5mm, to better balance computational accuracy and efficiency, avoiding a doubling of solution time or distortion of computational accuracy. Furthermore, after mesh generation, the mesh quality can be manually checked to ensure that the warpage, aspect ratio, and other indicators of the elements meet the solution requirements of explicit dynamic analysis.

[0023] In method 100, step 104 can create weld elements at the weld location of the three-dimensional model and extend adjacent heat-affected zone elements from the weld elements based on the extension command.

[0024] In this embodiment, taking the import into HyperMesh software as an example, the weld seam command in the one-dimensional connector panel can automatically generate connection elements (i.e., weld seam elements) that simulate the force transmission path of a weld seam between two sets of mesh elements. Due to the high temperature of welding, the microstructure and mechanical properties of the base material on both sides of the weld seam are significantly weakened. This area is called the heat-affected zone (HAZ). It can be expanded by one or two layers adjacent to each other using the Expand command in the software (usually one layer of mesh size is selected, which is about 5mm, equivalent to the actual width of the HAZ). At this time, the part of the base material area elements that are directly connected to the weld seam element and selected by the Expand command will be defined as HAZ elements to distinguish them from the rest of the regular base material area elements.

[0025] In method 100, step 106 can assign a preset first plastic material curve to the base material region unit and assign a second plastic material curve to the weld unit and the heat-affected zone unit. The second plastic material curve is obtained by multiplying the stress value in the first plastic material curve by a reduction factor, and the reduction factor is determined based on the ratio of the weld material strength to the base material strength.

[0026] In this embodiment, to accurately simulate the yielding and subsequent deformation behavior of materials under impact, it is necessary to assign complete plastic stress-strain curves (i.e., plastic material curves) to different regions. For the base material region units, the true stress-true plastic strain curve obtained from the material's uniaxial tensile test can be directly assigned, i.e., the first plastic material curve. For the weld units and heat-affected zone units in the weld region, due to the welding thermal cycle, the material strength in this region is generally lower than that of the base material. Therefore, this weakening effect is simulated by strength reduction. Specifically, based on the data provided by the material supplier, the ratio of the weld material strength to the base material strength used in the battery pack can be determined. For example, for aluminum profiles, the strength of the weld and heat response zone is approximately 60% of the base material strength, so the reduction factor can be determined to be 0.6. In this way, by uniformly multiplying the stress value portion of the first plastic material curve by this reduction factor, while keeping the strain value portion unchanged, a new second plastic material curve with lower strength is obtained, and this curve is assigned to the weld unit and heat-affected zone unit. This method can simply and efficiently generate relatively accurate plastic material curves, avoiding complex welding process simulations, but can effectively capture the risk of the weld zone failing before the base material.

[0027] In method 100, step 108 can import the three-dimensional model with the plastic material curve into the finite element solver to obtain the equivalent plastic strain of the weld output by the finite element solver, so as to generate simulation results to characterize whether there is a risk of failure of the weld based on the equivalent plastic strain.

[0028] In this embodiment, after the 3D model is assigned the corresponding plastic material curve and is ready, it can be exported from HyperMesh and imported into a finite element solver (such as Abaqus) for solving. The finite element solver can select the explicit dynamic analysis module and the equivalent plastic strain option during the solution process. The explicit dynamic analysis module is suitable for simulating short-term, high-speed impact and collision problems and can efficiently handle complex contact and nonlinear materials. Equivalent plastic strain is an important indicator for measuring the cumulative plastic damage of a material, and it will be used directly to determine failure later. After completing the option settings, the finite element solver can output the specific value of the equivalent plastic strain corresponding to the weld in the 3D model. Based on the magnitude of this value, corresponding simulation results can be generated. For example, the maximum equivalent plastic strain value can be determined from the second plastic material curve. If the output equivalent plastic strain is less than this maximum value, it is considered that there is no failure; otherwise, it is considered that there is failure.

[0029] In one possible implementation, the three-dimensional model of the battery pack housing is imported into finite element preprocessing software, including:

[0030] Based on the mathematical model information of the battery pack, a 3D model is constructed in 3D modeling software;

[0031] In response to modification commands for the 3D model, the 3D model is adjusted based on the modification commands. The adjusted 3D model is then imported into the finite element preprocessing software. The modification commands are used to geometrically simplify the 3D model and remove information that does not affect stress.

[0032] In this embodiment, the mathematical model information of the battery pack (such as information data on the location of the top cover, lower casing, cell modules, battery system, battery disconnection unit, casing welds, etc.) is acquired and imported into 3D modeling software (such as CATIA, SolidWorks, etc.). At this stage, the 3D model typically contains a large number of details used for manufacturing definitions. Directly using it for simulation will lead to problems such as poor mesh quality and difficulty in calculation convergence. Therefore, the 3D model will first undergo geometric cleanup. Users can select and specify the locations and items to be cleaned, and then generate corresponding modification instructions, allowing the terminal to modify the 3D model in the 3D modeling software according to these instructions. Modification mainly includes two types of processes: one is geometric simplification, such as repairing broken surfaces, repairing missing surfaces, cracks, or discontinuities in the model to ensure the integrity and closure of the geometric shape. The other is cleaning up information that does not affect stress, such as removing features that have little impact on the overall stress distribution but significantly increase the number of meshes and distortion, such as small rounded corners with a radius less than 3mm, chamfers, raised nameplate logos, and non-load-bearing steps around bolt holes, which easily make the local mesh too dense and severely slow down the calculation speed. Ultimately, a geometrically regular and feature-simplified model can be obtained, laying the foundation for subsequent high-quality mesh generation.

[0033] In one possible implementation, meshing the 3D model includes:

[0034] Shell meshes are used to partition the thin-walled structure of the 3D model, and solid meshes are used to partition the non-thin-walled structure of the 3D model.

[0035] In this embodiment, for thin-walled structures such as crossbeams, longitudinal beams, and frames of the battery pack, whose thickness is much smaller than their length and width, their geometric mid-surfaces can be uniformly extracted and divided into shell networks. This allows the divided shell units to accurately simulate the bending and membrane effects of thin-walled structures. For other non-thin-walled structures, conventional three-dimensional solid network partitioning will be used.

[0036] In one possible implementation, after meshing the 3D model, the method further includes:

[0037] Assign basic material properties to the divided mesh;

[0038] After extending adjacent heat-affected zone elements from the weld element based on the extension command, it also includes:

[0039] For each heat-affected zone element, a thickness attribute is set for the heat-affected zone element based on the basic material properties of the corresponding parent material area element.

[0040] In this embodiment, basic material properties such as density, elastic modulus, Poisson's ratio, and thickness can be assigned to all the meshes. These parameters can be obtained from the property tables provided by the material supplier. After generating the heat-affected zone (HAZ) elements, the selected HAZ elements can be moved into a new component. Based on the thickness attribute in the basic material properties of the parent material element to which the HAZ elements are attached, the HAZ elements are set with the same thickness attribute. This allows for the subsequent assignment of material properties to HAZs of different thicknesses, ensuring that the stress and strain of HAZ elements of different thicknesses are independent during simulation and are not treated as a continuous whole, thus preventing significant errors.

[0041] In one possible implementation, a three-dimensional model with a plastic material curve is imported into a finite element solver to obtain the equivalent plastic strain corresponding to the weld output by the finite element solver, including:

[0042] The 3D model with the plastic material curve is converted into a format compatible with the finite element solver and imported into the finite element solver. Gravity loads and boundary conditions are set for the 3D model in the finite element solver to obtain the equivalent plastic strain corresponding to the weld output by the finite element solver.

[0043] In this embodiment, the 3D model can be converted from the OptiStruct template to the Abaqus template using a Convert tool in the finite element preprocessing software, for example, to facilitate data compatibility when importing it into Abaqus for explicit collision calculations. Before solving, gravity loads and boundary conditions are set. The gravity load applies a gravitational field to the entire 3D model to simulate its own weight. Boundary conditions can be applied at the mounting point where the battery pack connects to the vehicle body, applying a half-sine or other waveform impact acceleration pulse load. After setting these parameters, the finite element solver performs the solution to obtain the equivalent plastic strain corresponding to the weld.

[0044] In one possible implementation, simulation results are generated based on equivalent plastic strain to characterize whether there is a risk of weld failure, including:

[0045] Based on the comparison between the equivalent plastic strain and the maximum plastic deformation of the second plastic material curve, simulation results are generated. When the equivalent plastic strain is greater than the maximum plastic deformation, the simulation results indicate that the weld has a risk of failure. When the equivalent plastic strain is not greater than the maximum plastic deformation, the simulation results indicate that the weld does not have a risk of failure.

[0046] In this embodiment, the equivalent plastic strain on the weld element and heat-affected zone element in the weld area is determined by the cloud map output by the Abaqus post-processing module, and compared with the maximum plastic deformation read from the second plastic material curve. If the equivalent plastic strain is greater than the maximum plastic deformation, it is determined that the weld area has a risk of cracking failure, and the welding process or structure needs to be optimized. If the equivalent plastic strain is not greater than the maximum plastic deformation, it is determined that the weld area has not failed and meets the strength design requirements.

[0047] Figure 2 This document illustrates a schematic diagram of the structure of a modeling and simulation apparatus 200 for the welding area of ​​a battery pack casing, representing some embodiments of this disclosure. The various embodiments in this specification are described in a progressive manner; similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the apparatus embodiments are substantially similar to the method embodiments, and therefore the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. Figure 2 As shown, the device 200 includes a mesh generation module 201, which is configured to import the three-dimensional model of the battery pack into the finite element preprocessing software and perform mesh generation on the three-dimensional model.

[0048] The extension module 202 is configured to create weld elements at the weld location of the 3D model, and extend adjacent heat-affected zone elements from the weld elements based on the extension command;

[0049] The curve setting module 203 is configured to assign a preset first plastic material curve to the base material area unit and a second plastic material curve to the weld unit and the heat-affected zone unit. The second plastic material curve is obtained by multiplying the stress value in the first plastic material curve by a reduction factor. The reduction factor is determined based on the ratio of the weld material strength to the base material strength.

[0050] Simulation module 204 is configured to import a three-dimensional model with a plastic material curve into a finite element solver to obtain the equivalent plastic strain of the weld output by the finite element solver, so as to generate simulation results based on the equivalent plastic strain to characterize whether there is a risk of failure in the weld.

[0051] In one possible implementation, the partitioning module 201 is further configured with mathematical model information based on the battery pack to construct a three-dimensional model in three-dimensional modeling software; in response to a modification instruction for the three-dimensional model, the three-dimensional model is adjusted based on the modification instruction, and the adjusted three-dimensional model is imported into the finite element preprocessing software. The modification instruction is used to geometrically simplify the three-dimensional model and remove information that does not affect stress.

[0052] In one possible implementation, the partitioning module 201 is further configured to perform shell network partitioning on the thin-walled structure of the 3D model and 3D solid network partitioning on the non-thin-walled structure of the 3D model.

[0053] In one possible implementation, the dividing module 201 is also configured to assign basic material properties to the divided mesh;

[0054] The extension module 202 is also configured to set thickness attributes for each heat-affected zone unit based on the basic material properties of the parent material region unit corresponding to the heat-affected zone unit.

[0055] In one possible implementation, the simulation module 204 is further configured to convert the three-dimensional model with the plastic material curve into a format compatible with the finite element solver and import it into the finite element solver, set gravity loads and boundary conditions for the three-dimensional model in the finite element solver, and obtain the equivalent plastic strain corresponding to the weld output by the finite element solver.

[0056] In one possible implementation, the simulation module 204 is further configured to generate simulation results based on the comparison between the equivalent plastic strain and the maximum plastic deformation of the second plastic material curve. The simulation results indicate that the weld has a risk of failure when the equivalent plastic strain is greater than the maximum plastic deformation, and that the weld does not have a risk of failure when the equivalent plastic strain is not greater than the maximum plastic deformation.

[0057] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this specification is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in or transmitted through a computer-readable storage medium. The computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., Digital Versatile Discs (DVDs)), or semiconductor media (e.g., Solid State Disks (SSDs)).

[0058] Figure 3 A block diagram of an electronic device 300 that can implement various embodiments of the present disclosure is shown. For example... Figure 3 As shown, the electronic device 300 includes a processor 310, a disk drive 320, an input / output interface 330, a network interface 340, and a memory 350. The processor 310, disk drive 320, input / output interface 330, network interface 340, and memory 350 can communicate with each other via a communication bus 360.

[0059] The processor 310 can be implemented using a general-purpose CPU, microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits to execute relevant programs in order to implement the technical solution provided in this application.

[0060] The memory 350 can be implemented in the form of ROM (Read Only Memory), RAM (Read Access Memory), static memory, dynamic storage devices, etc. The memory 350 can store the operating system 351 used to control the operation of the electronic device 300, and the basic input / output system (BIOS) 352 used to control the low-level operations of the electronic device 300. Additionally, it can store a web browser 353, a data storage management system 354, etc. In summary, when the technical solution provided in this application is implemented through software or firmware, the relevant program code is stored in the memory 350 and is called and executed by the processor 310.

[0061] Input / output interface 330 is used to connect input / output modules to realize information input and output. Input / output modules can be configured as components in the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touch screens, microphones, various sensors, etc., and output devices may include displays, vibrators, indicator lights, etc.

[0062] Network interface 340 is used to connect a communication module (not shown in the figure) to enable communication and interaction between the device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0063] Bus 360 includes a pathway for transmitting information between various components of the device, such as processor 310, disk drive 320, input / output interface 330, network interface 340, and memory 350.

[0064] It should be noted that although the above-described device only shows the processor 310, disk drive 320, input / output interface 330, network interface 340, memory 350, bus 360, etc., in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the method of this application, and does not necessarily include all the components shown in the figures.

[0065] The program code used to implement the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0066] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. Machine-readable media can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing. Furthermore, although operations are depicted in a specific order, this should be understood as requiring that such operations be performed in the specific order shown or in sequential order, or requiring that all illustrated operations be performed to achieve the desired result. In certain environments, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the foregoing discussion, these should not be construed as limiting the scope of this disclosure. Certain features described in the context of individual embodiments may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented individually or in any suitable sub-combination in multiple implementations.

[0067] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

Claims

1. A modeling and simulation method for the welding area of ​​a battery pack casing, characterized in that, The method includes: Import the 3D model of the battery pack into the finite element preprocessing software, and perform mesh generation on the 3D model; Weld elements are created at the weld locations in the three-dimensional model, and adjacent heat-affected zone elements are extended from the weld elements based on the extension command; A preset first plastic material curve is assigned to the base material region unit, and a second plastic material curve is assigned to the weld unit and the heat-affected zone unit. The second plastic material curve is obtained by multiplying the stress value in the first plastic material curve by a reduction factor, and the reduction factor is determined based on the ratio of the weld material strength to the base material strength. The three-dimensional model with the plastic material curve is imported into the finite element solver to obtain the equivalent plastic strain corresponding to the weld output by the finite element solver, so as to generate simulation results to characterize whether there is a risk of failure of the weld based on the equivalent plastic strain.

2. The modeling and simulation method for the welding area of ​​a battery pack casing according to claim 1, characterized in that, Importing the 3D model of the battery pack housing into the finite element preprocessing software includes: Based on the mathematical model information of the battery pack, a 3D model is constructed in 3D modeling software; In response to a modification instruction for the three-dimensional model, the three-dimensional model is adjusted based on the modification instruction, and the adjusted three-dimensional model is imported into the finite element preprocessing software. The modification instruction is used to geometrically simplify the three-dimensional model and remove information that does not affect stress.

3. The modeling and simulation method for the welding area of ​​a battery pack casing according to claim 1, characterized in that, The meshing of the 3D model includes: Shell mesh partitioning is performed on the thin-walled structure of the three-dimensional model, and three-dimensional solid mesh partitioning is performed on the non-thin-walled structure of the three-dimensional model.

4. The modeling and simulation method for the welding area of ​​a battery pack casing according to claim 1, characterized in that, After meshing the 3D model, the process further includes: Assign basic material properties to the divided mesh; After extending adjacent heat-affected zone units from the weld unit based on the extension command, the method further includes: For each heat-affected zone unit, a thickness attribute is set for the heat-affected zone unit based on the basic material properties of the parent material region unit corresponding to the heat-affected zone unit.

5. The modeling and simulation method for the welding area of ​​a battery pack casing according to claim 1, characterized in that, The process of importing the three-dimensional model with the plastic material curve into the finite element solver to obtain the equivalent plastic strain corresponding to the weld output by the finite element solver includes: The three-dimensional model with the plastic material curve is converted into a format compatible with the finite element solver and imported into the finite element solver. Gravity loads and boundary conditions are set for the three-dimensional model in the finite element solver to obtain the equivalent plastic strain corresponding to the weld output by the finite element solver.

6. The modeling and simulation method for the welding area of ​​a battery pack casing according to claim 1, characterized in that, The process of generating simulation results based on the equivalent plastic strain to characterize whether there is a risk of weld failure includes: Based on the comparison between the equivalent plastic strain and the maximum plastic deformation of the second plastic material curve, simulation results are generated. The simulation results indicate that the weld has a risk of failure when the equivalent plastic strain is greater than the maximum plastic deformation, and that the weld does not have a risk of failure when the equivalent plastic strain is not greater than the maximum plastic deformation.

7. A modeling and simulation device for the welding area of ​​a battery pack casing, characterized in that, The device includes: The mesh generation module is configured to import the 3D model of the battery pack into the finite element preprocessing software and perform mesh generation on the 3D model. An extension module is configured to create weld elements at the weld location in the 3D model and extend adjacent heat-affected zone elements from the weld elements based on extension commands. The curve setting module is configured to assign a preset first plastic material curve to the base material area unit, and assign a second plastic material curve to the weld unit and the heat-affected zone unit. The second plastic material curve is obtained by multiplying the stress value in the first plastic material curve by a reduction factor, and the reduction factor is determined based on the ratio of the weld material strength to the base material strength. The simulation module is configured to import the three-dimensional model with the plastic material curve into the finite element solver to obtain the equivalent plastic strain corresponding to the weld output by the finite element solver, so as to generate simulation results to characterize whether there is a risk of failure of the weld based on the equivalent plastic strain.

8. An electronic device, characterized in that, include: One or more processors, and a memory associated with the one or more processors, the memory being used to store program instructions that, when read and executed by the one or more processors, perform the steps of the modeling and simulation method for the welding area of ​​a battery pack housing according to any one of claims 1-6.

9. A computer program product, characterized in that, The method includes a computer program that, when executed by a processor, implements a modeling and simulation method for the welding area of ​​a battery pack housing according to any one of claims 1-6.

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