Lithium battery diaphragm modeling method and device based on Thiessen polygon and computer equipment

Abstract

The invention discloses a lithium battery diaphragm modeling method and device based on Thiessen polygon, computer equipment and a medium. The invention relates to the technical field of model construction, and the method comprises the steps: obtaining a microscopic image of the morphology of a lithium battery diaphragm, and selecting at least two reference images for modeling from the microscopic image; for each reference image, at least two Thiessen polygon unit control points are selected according to the size of pores in the reference image, and a Thiessen polygon is generated; selecting a central point of each Thiessen polygon unit, and processing the Thiessen polygon units according to the position of the central point of each Thiessen polygon unit to generate a lithium battery diaphragm two-dimensional model; and carrying out curve lofting and combination on the at least two generated lithium battery diaphragm two-dimensional models to generate a three-dimensional model of the lithium battery diaphragm. According to the method, the three-dimensional microscopic model capable of reflecting the internal structure of the lithium battery diaphragm can be simply and efficiently established.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of model building, and in particular to a lithium battery diaphragm modeling method, device, computer equipment and medium based on Thiessen polygons. Background Art

[0002] The quality of mechanical properties is an important indicator for evaluating lithium battery separators, and the importance of separator mechanical properties is reflected in many scenarios. For example: the separator needs to withstand tension during cell assembly; lithium ion intercalation and deintercalation during battery cycling will cause squeezing pressure on the separator; the separator needs to withstand thermal stress when the battery temperature rises; and the separator needs to resist external complex loads when an accident occurs. In order to facilitate the study of the mechanical properties of the separator and reduce research costs, numerical simulation methods are very necessary. Therefore, when using numerical simulation methods, the separator needs to be modeled.

[0003] At present, most of the modeling of lithium battery separators uses a macroscopic homogenization model to study the mechanical properties of the separator. This model can predict the macroscopic deformation of the separator under various loads. When the deformation reaches the maximum value, the separator breaks, and the separator breakage means the occurrence of a short circuit. When the separator is deformed under load, it manifests itself as a change in thickness and shape at the macro level and a change in pore structure at the micro level. The change in pore structure will affect the ion transport performance of the separator. However, the macroscopic homogenization model cannot simulate the changes in the internal pore structure of the separator when the separator is deformed. Summary of the invention

[0004] The embodiments of the present invention provide a lithium battery diaphragm modeling method, device, computer equipment and medium based on Thiessen polygons, aiming to solve the problem that the existing lithium battery diaphragm modeling cannot simulate the pore structure of the lithium battery diaphragm.

[0005] In a first aspect, an embodiment of the present invention provides a lithium battery diaphragm modeling method based on Thiessen polygons, comprising:

[0006] Acquire a microscopic image of the morphology of a lithium battery separator and select at least two reference images for modeling from the microscopic image;

[0007] For each reference image, selecting at least two Thiessen polygon unit control points according to the size of the pores in the reference image and generating Thiessen polygons;

[0008] Select the center point of each Thiessen polygon unit, and scale the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery separator;

[0009] The at least two generated two-dimensional models of the lithium battery separator are lofted and combined through curves to generate a three-dimensional model of the lithium battery separator.

[0010] In a second aspect, an embodiment of the present invention further provides a lithium battery diaphragm modeling device based on Thiessen polygons, comprising:

[0011] An acquisition unit, used to acquire a microscopic image of the lithium battery separator morphology and select at least two reference images for modeling from the microscopic image;

[0012] A first generating unit is used for selecting at least two Thiessen polygon unit control points for each reference image according to the size of the pores in the reference image and generating Thiessen polygons;

[0013] The second generating unit is used to select the center point of each Thiessen polygon unit, and scale the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery separator;

[0014] The third generating unit is used to generate a three-dimensional model of the lithium battery separator by curve lofting and combining the at least two generated two-dimensional models of the lithium battery separator.

[0015] In a third aspect, an embodiment of the present invention further provides a computer device, which includes a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the above method when executing the computer program.

[0016] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the storage medium stores a computer program, and the computer program can implement the above method when executed by a processor.

[0017] The embodiment of the present invention provides a lithium battery diaphragm modeling method, device, computer equipment and medium based on Thiessen polygons. The method includes: obtaining a microscopic image of the morphology of the lithium battery diaphragm and selecting at least two reference images for modeling from the microscopic image; for each reference image, selecting at least two Thiessen polygon unit control points according to the size of the pores in the reference image and generating Thiessen polygons; selecting the center point of each Thiessen polygon unit, and processing the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery diaphragm; and generating a three-dimensional model of the lithium battery diaphragm by curve lofting and combining the generated at least two two-dimensional models of the lithium battery diaphragm. The technical solution of the embodiment of the present invention can simply and efficiently establish a three-dimensional microscopic model that can reflect the internal structure of the lithium battery diaphragm. The parameters such as pore distribution and porosity in the three-dimensional model of the lithium battery diaphragm can be adjusted, which is suitable for simulation research under various physical fields, especially the mechanical property simulation of the lithium battery diaphragm. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of a flow chart of a lithium battery diaphragm modeling method based on Thiessen polygons provided in an embodiment of the present invention;

[0020] Figure 2 A scanning electron microscope image of a polyethylene diaphragm prepared by a wet process in a lithium battery diaphragm modeling method based on Thiessen polygons provided in an embodiment of the present invention;

[0021] Figure 3 A schematic diagram of a model building process in a lithium battery diaphragm modeling method based on Thiessen polygons provided in an embodiment of the present invention;

[0022] Figure 4 A schematic flow chart of another lithium battery diaphragm modeling method based on Thiessen polygons provided in an embodiment of the present invention;

[0023] Figure 5 A schematic block diagram of a lithium battery diaphragm modeling device based on Thiessen polygons provided in an embodiment of the present invention;

[0024] Figure 6 A schematic block diagram of a computer device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0027] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0028] It should be further understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0029] As used in this specification and the appended claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0030] See also Figure 1 , Figure 1 1 is a flow chart of a lithium battery diaphragm modeling method based on Thiessen polygons provided by an embodiment of the present invention. The lithium battery diaphragm modeling method based on Thiessen polygons is described in detail below. Figure 1 As shown, the method includes the following steps S110-S140.

[0031] S110, obtaining a microscopic image of the lithium battery separator morphology and selecting at least two reference images for modeling from the microscopic image.

[0032] In the embodiments of the present invention, in order to explain the present solution more clearly, a brief description is given of the lithium battery separator. In the structure of the lithium battery, the separator is one of the key inner layer components. The performance of the separator determines the interface structure and internal resistance of the battery, directly affecting the battery's capacity, cycle and safety performance. The separator with excellent performance plays an important role in improving the overall performance of the battery. The main function of the lithium battery separator is to separate the positive and negative electrodes of the battery to prevent the two electrodes from contacting and short-circuiting. In addition, it also has the function of allowing electrolyte ions to pass through. The separator material is non-conductive, and its physical and chemical properties have a great influence on the performance of the battery. In a specific embodiment, the lithium-ion battery separator used for modeling is a wet polyethylene separator. The wet polyethylene separator has undergone biaxial stretching, so it has uniform pores that are approximately circular, and the thickness direction of the wet polyethylene separator shows a multi-layer laminated structure.

[0033] In one embodiment, the method further includes: obtaining a microscopic image of the lithium-ion battery separator by atomic force microscopy or scanning electron microscopy and selecting at least two micron-level reference images with obvious pore features for modeling. Specifically, the microscopic morphology image of the lithium battery separator can be obtained by atomic force microscopy, scanning electron microscopy, etc. The size of the microscopic morphology image is at the micron level, and the pore morphology size of the separator can be clearly observed. Figure 2 As shown in the figure, the thickness of the wet polyethylene membrane is 16um, the pore size is between 70nm and 80nm, and the porosity is 40.4%. In addition, the modeling area can be selected according to the modeling requirements, and any area that can reflect the morphology of the membrane can be selected. For example: Figure 2 In the figure, a 1um×1um area is selected as a reference image for modeling the lithium battery separator. It should be noted that after two-dimensional modeling is performed for each reference image, another reference image needs to be selected from the microscopic image of the lithium-ion battery separator for two-dimensional modeling again, and the final three-dimensional model is constructed through multiple layers of two-dimensional models.

[0034] S120 . For each reference image, select at least two Thiessen polygon unit control points according to the size of the pores in the reference image and generate Thiessen polygons.

[0035] In an embodiment of the present invention, for each selected reference image, it is necessary to select at least two Thiessen polygon unit control points according to the size of the pores in the reference image and generate Thiessen polygons. Thiessen polygons, also known as Voronoi diagrams, are a set of continuous polygons composed of perpendicular bisectors connecting two adjacent line segments. The distance from any point in a Thiessen polygon to the control points that constitute the polygon is less than the distance to other polygon control points. In one embodiment, the step of selecting at least two Thiessen polygon unit control points according to the size of the pores in the reference image and generating Thiessen polygons also includes: controlling the pore distribution of the lithium battery diaphragm model by selecting at least two different Thiessen polygon unit control points in the reference image. The selection of Thiessen polygon control points can be manually selected with reference to the microscopic scanning electron microscope image of the lithium battery diaphragm, or automatically selected through an image processing program. Specifically, with reference to Figure 3 The 1um×1um reference image selected in the first picture is used as an example to illustrate. The relatively obvious pores in the image are selected as the control points for generating Thiessen polygon units, and the parametric modeling plug-in is used to generate Thiessen polygons in this area. Figure 3 As shown in the second image, this selected operation can control and adjust the pore distribution of the generated membrane model.

[0036] S130, selecting the center point of each Thiessen polygon unit, and processing the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery separator.

[0037] In the embodiment of the present invention, the center point of each Thiessen polygon unit is selected, and the Thiessen polygon unit is scaled according to the position of the center point of each Thiessen polygon unit. Figure 3 As shown in the second image in the figure, the center point of each Thiessen polygon unit can be scaled according to a certain ratio to obtain Figure 3 The third image in . The scaling ratio can be controlled by taking a natural number between 0 and 1.

[0038] In one embodiment, the step of processing the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of a lithium battery diaphragm includes: scaling each Thiessen polygon unit in proportion to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery diaphragm, and adjusting the scaling ratio to control the pore size and porosity of the lithium battery diaphragm model. Specifically, after the Thiessen polygon unit is established, pores need to be generated. Take the center point of each Thiessen polygon unit and scale each unit in proportion relative to its center point. This scaling operation can control the pore size and porosity of the generated model after adjustment. In the actual modeling process, the scaling ratio can be selected according to the model requirements, and the scaling ratio parameter affects the porosity of the model.

[0039] S140, generating a three-dimensional model of the lithium battery separator by curve lofting and combining the at least two generated two-dimensional models of the lithium battery separator.

[0040] In an embodiment of the present invention, it is necessary to combine the two-dimensional model of the lithium battery diaphragm to obtain the three-dimensional model curve of the lithium battery diaphragm. Therefore, in the selection process, it is necessary to select at least two reference images to generate at least two two-dimensional models of the lithium battery diaphragm, and generate the three-dimensional model of the lithium battery diaphragm by curve lofting and combination. Specifically, since the wet-process polyethylene diaphragm is a multi-layer structure in the thickness direction, four reference images are selected to establish a four-layer lithium battery diaphragm two-dimensional model. Then, the parametric modeling plug-in is used to perform curve lofting and combination to complete the establishment of the three-dimensional model of the lithium battery diaphragm. For the specific three-dimensional model structure of the lithium battery diaphragm, please refer to Figure 3 The model diagram shown in the fifth figure.

[0041] In one embodiment, after the step of generating a three-dimensional model of the lithium battery separator by curve lofting and combining the generated at least two two-dimensional models of the lithium battery separator, the method further includes: smoothing the edges and corners of the three-dimensional model of the lithium battery separator, and then applying the three-dimensional model of the lithium battery separator to the stress field simulation. Specifically, refer to Figure 4 Another lithium battery diaphragm modeling method based on Thiessen polygons is shown, and its specific implementation steps are as follows: First, obtain the diaphragm SEM image and select an area of ​​appropriate size as a modeling reference object. Then, using Thiessen polygons as the basic model, select the pores in the diaphragm SEM image as the control points of Thiessen polygons to generate Thiessen polygons. Then, select the center point of each unit of the established Thiessen polygons, so that each unit is scaled in proportion to its center point, and generate the fiber part and the pore part of the diaphragm. Finally, repeatedly select an area of ​​appropriate size and perform the above steps to establish a multi-layer similar structure, and complete the establishment and optimization of the model through operations such as curve lofting, combination and smoothing. In this embodiment, an optimization method is given for the purpose of stress field simulation. The diaphragm model is a grid model, and the number of initial model grids is huge, and it is difficult to generate a general three-dimensional solid model file suitable for simulation. Therefore, the model can be simplified by coarsening the grid and deleting the grid to improve the modeling efficiency. In addition, the model is surrounded by complex and unconnected boundaries. Considering the boundary problems that may occur in the stress field simulation, the protruding fiber structure around the three-dimensional model was cut off to make its shape a regular square to facilitate the application of boundary stress.

[0042] In a specific embodiment, the step of smoothing the angular parts of the boundary of the three-dimensional model of the lithium battery separator includes: cutting off the protruding discontinuous parts around the three-dimensional model of the lithium battery separator through a Boolean difference operation to make the surface of the three-dimensional model of the lithium battery separator smooth. Specifically, in the three-dimensional modeling process, model cutting can be used to divide the model into multiple parts or create new geometric bodies or edit specific parts of the model. Using cutting tools Most 3D modeling software provides a variety of cutting tools, which include knives, slices, face segmentation, etc., which can perform cutting operations on the surface or inside of the model. By selecting a cutting tool and operating on the model, the model can be cut into multiple parts or a new geometric body can be created. Among them, Boolean operations can be used to merge, intersect or cut two or more models. Use Boolean operations to cut a model into multiple parts, or merge multiple models to create a new model. Use the Boolean difference operation in the modeling software to cut off the protruding discontinuous parts around the model so that the model has a smooth surface. The size of the cut part also depends on the requirements for the model. Please refer to Figure 3The model shown in the sixth figure shows that the size of the final built 3D model is 1um×1um×0.75um. It is worth noting that the final 3D model built in this solution is not just the cube in the example. The model can be cut according to actual specific needs. For example, the cube 3D model built can be cut into other 3D geometric bodies such as spheres or cylinders.

[0043] In summary, in this embodiment, a microscopic image of the morphology of a lithium battery diaphragm is obtained and at least two reference images for modeling are selected from the microscopic image; for each reference image, at least two Thiessen polygon unit control points are selected according to the size of the pores in the reference image and Thiessen polygons are generated; the center point of each Thiessen polygon unit is selected, and the Thiessen polygon unit is scaled according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery diaphragm; the at least two generated two-dimensional models of the lithium battery diaphragm are lofted and combined to generate a three-dimensional model of the lithium battery diaphragm. The technical solution of the embodiment of the present invention can simply and efficiently establish a three-dimensional microscopic model that can reflect the internal structure of the lithium battery diaphragm. The parameters such as pore distribution and porosity in the three-dimensional model of the lithium battery diaphragm can be adjusted, which is suitable for simulation research under various physical fields, especially the simulation of the mechanical properties of the lithium battery diaphragm.

[0044] Figure 5 is a schematic block diagram of a lithium battery diaphragm modeling device 200 based on Thiessen polygons provided in an embodiment of the present invention. Figure 5 As shown, corresponding to the above-mentioned lithium battery diaphragm modeling method based on Thiessen polygons, the present invention also provides a lithium battery diaphragm modeling device 200 based on Thiessen polygons. The lithium battery diaphragm modeling device 200 based on Thiessen polygons includes a unit for executing the above-mentioned lithium battery diaphragm modeling method based on Thiessen polygons, and the device can be configured in a computer device. Specifically, please refer to Figure 5 The lithium battery diaphragm modeling device 200 based on Thiessen polygons includes an acquisition unit 201, a first generation unit 202, a second generation unit 203, and a third generation unit 204.

[0045] Among them, the acquisition unit 201 is used to acquire a microscopic image of the lithium battery diaphragm morphology and select at least two reference images for modeling from the microscopic image; the first generation unit 202 is used to select at least two Thiessen polygon unit control points and generate Thiessen polygons for each reference image according to the size of the pores in the reference image; the second generation unit 203 is used to select the center point of each Thiessen polygon unit, and process the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery diaphragm; the third generation unit 204 is used to generate a three-dimensional model of the lithium battery diaphragm by curve lofting and combining the at least two generated two-dimensional models of the lithium battery diaphragm.

[0046] In some embodiments, such as the present embodiment, the second generation unit 203 is also used to scale each Thiessen polygon unit in proportion to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of a lithium battery diaphragm, and to control the pore size and porosity of the lithium battery diaphragm model by adjusting the scaling ratio.

[0047] In some embodiments, such as the present embodiment, the first generating unit 202 is further configured to control the pore distribution of the lithium battery separator model by selecting at least two different Thiessen polygon unit control points in the reference image.

[0048] In certain embodiments, such as the present embodiment, the third generation unit 204 is further used to stack at least two two-dimensional lithium battery models and perform curve lofting operations on each Thiessen polygon unit to obtain a three-dimensional surface model of the lithium battery diaphragm, and then convert the three-dimensional surface model into a mesh and combine them into a whole to generate a three-dimensional model of the lithium battery diaphragm; smooth the edges and corners of the boundary of the three-dimensional model of the lithium battery diaphragm, and then apply the three-dimensional model of the lithium battery diaphragm to stress field simulation; and cut off the protruding discontinuous parts around the three-dimensional model of the lithium battery diaphragm through a Boolean difference operation to make the surface of the three-dimensional model of the lithium battery diaphragm smooth.

[0049] In some embodiments, such as the present embodiment, the lithium-ion battery separator includes a wet-process polyethylene separator, and the acquisition unit 201 is further used to acquire a microscopic image of the lithium-ion battery separator through an atomic force microscope or a scanning electron microscope and select at least two micron-level reference images with obvious pore features for modeling.

[0050] The lithium battery diaphragm modeling device based on Thiessen polygons can be implemented in the form of a computer program. The computer program can be used in Figure 6 Runs on the computer device shown.

[0051] See also Figure 6 , Figure 6300 is a schematic block diagram of a computer device provided by an embodiment of the present invention. The computer device 300 is a device having a lithium battery diaphragm modeling function based on Thiessen polygons.

[0052] See also Figure 6 The computer device 300 includes a processor 302 , a memory and a network interface 305 connected via a system bus 301 , wherein the memory may include a non-volatile storage medium 303 and an internal memory 304 .

[0053] The non-volatile storage medium 303 can store an operating system 3031 and a computer program 3032. When the computer program 3032 is executed, the processor 302 can execute a lithium battery separator modeling method based on Thiessen polygons.

[0054] The processor 302 is used to provide computing and control capabilities to support the operation of the entire computer device 300 .

[0055] The internal memory 304 provides an environment for the operation of the computer program 3032 in the non-volatile storage medium 303. When the computer program 3032 is executed by the processor 302, the processor 302 can execute a lithium battery diaphragm modeling method based on Thiessen polygons.

[0056] The network interface 305 is used to communicate with other devices over the network. Figure 6 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device 300 to which the solution of the present invention is applied. The specific computer device 300 may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0057] The processor 302 is used to run a computer program 3032 stored in the memory to implement any embodiment of the above-mentioned lithium battery diaphragm modeling method based on Thiessen polygons.

[0058] It should be understood that in the embodiment of the present invention, the processor 302 may be a central processing unit (CPU), and the processor 302 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0059] It is understood by those skilled in the art that all or part of the processes in the method for implementing the above embodiment can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a storage medium, which is a computer-readable storage medium. The computer program is executed by at least one processor in the computer system to implement the process steps of the embodiment of the above method.

[0060] Therefore, the present invention also provides a storage medium. The storage medium may be a computer-readable storage medium. The storage medium stores a computer program. When the computer program is executed by a processor, the processor executes any embodiment of the above-mentioned lithium battery diaphragm modeling method based on Thiessen polygons.

[0061] The storage medium may be any computer-readable storage medium that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a magnetic disk, or an optical disk.

[0062] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0063] In the several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of each unit is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0064] The steps in the method of the embodiment of the present invention can be adjusted in order, combined and deleted according to actual needs. The units in the device of the embodiment of the present invention can be combined, divided and deleted according to actual needs. In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0065] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for a computer device to execute all or part of the steps of the method described in each embodiment of the present invention.

[0066] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0067] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

[0068] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A lithium battery diaphragm modeling method based on Thiessen polygons, characterized in that: include: Acquire a microscopic image of the morphology of a lithium battery separator and select at least two reference images for modeling from the microscopic image; For each reference image, selecting at least two Thiessen polygon unit control points according to the size of the pores in the reference image and generating Thiessen polygons; Select the center point of each Thiessen polygon unit, and process the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery separator; The at least two generated two-dimensional models of the lithium battery separator are lofted and combined through curves to generate a three-dimensional model of the lithium battery separator.

2. The method according to claim 1, characterized in that The step of processing the Thiessen polygon units according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery separator includes: According to the position of the center point of each Thiessen polygon unit, each Thiessen polygon unit is scaled in the same proportion to generate a two-dimensional model of the lithium battery separator. The pore size and porosity of the lithium battery separator model are controlled by adjusting the scaling ratio.

3. The method according to claim 1, characterized in that The step of selecting at least two Thiessen polygon unit control points according to the size of the pores in the reference image and generating Thiessen polygons also includes: The pore distribution of the lithium battery separator model is controlled by selecting at least two different Thiessen polygon unit control points in the reference image.

4. The method according to claim 1, characterized in that: The step of generating a three-dimensional model of the lithium battery separator by curve lofting and combining the at least two generated two-dimensional models of the lithium battery separator comprises: At least two two-dimensional lithium battery models are stacked and curve lofting operations are performed on each Thiessen polygon unit to obtain a three-dimensional surface model of the lithium battery separator, and then the three-dimensional surface model is converted into a mesh and combined into a whole to generate a three-dimensional model of the lithium battery separator.

5. The method according to claim 1, characterized in that After the step of generating a three-dimensional model of the lithium battery separator by curve lofting and combining the at least two generated two-dimensional models of the lithium battery separator, the method further includes: The angular parts of the boundary of the three-dimensional model of the lithium battery separator are smoothed, and then the three-dimensional model of the lithium battery separator is applied to the stress field simulation.

6. The method according to claim 5, characterized in that The step of smoothing the angular portions of the boundary of the three-dimensional model of the lithium battery separator comprises: The protruding discontinuous parts around the three-dimensional model of the lithium battery separator are cut off through a Boolean difference operation to make the surface of the three-dimensional model of the lithium battery separator flat.

7. The method according to any one of claims 1 to 6, characterized in that: The lithium-ion battery separator comprises a wet polyethylene separator, and the method further comprises: A microscopic image of the lithium-ion battery separator is obtained by atomic force microscopy or scanning electron microscopy, and at least two micrometer-level reference images with obvious pore features are selected for modeling.

8. A lithium battery diaphragm modeling device based on Thiessen polygons, characterized in that: include: An acquisition unit, used to acquire a microscopic image of the lithium battery separator morphology and select at least two reference images for modeling from the microscopic image; A first generating unit is used for selecting at least two Thiessen polygon unit control points for each reference image according to the size of the pores in the reference image and generating Thiessen polygons; The second generating unit is used to select the center point of each Thiessen polygon unit, and process the Thiessen polygon unit according to the position of the center point of each Thiessen polygon unit to generate a two-dimensional model of the lithium battery separator; The third generating unit is used to generate a three-dimensional model of the lithium battery separator by curve lofting and combining the at least two generated two-dimensional models of the lithium battery separator.

9. A computer device, characterized in that: The computer device comprises a memory and a processor, the memory stores a computer program, and the processor implements the method according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 can be implemented.

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