Lithium battery coating gasket chamfer size obtaining method and system, electronic equipment and medium

Abstract

The invention discloses a lithium battery coating gasket chamfer size obtaining method, electronic equipment and a medium, and relates to the technical field of lithium battery coating, and the method mainly comprises the following steps: inputting obtained preset size parameters into a joint simulation model to output a simulation result; the joint simulation model comprises a two-dimensional model and a three-dimensional model, and the flow velocity distribution and the coating state output by the two-dimensional model form the input of the three-dimensional model; the simulation result is provided for configuring a gasket chamfer size of a coating die. According to the method, the size design of the gasket chamfer is optimized by adopting a local refined joint modeling simulation method, the advantages of fast calculation, high precision and parallelism of joint simulation are exerted, and efficient and accurate guidance is provided for the gasket chamfer design, so that the phenomenon that the edge of a coating film is ultrahigh is weakened by additionally arranging the chamfer at the outlet of the coating die head gasket, and the service life of the coating die head gasket is prolonged. And thus, the effect of optimizing the coating process is achieved.

Description

Technical Field

[0001] The present application relates to the field of lithium battery coating technology, and specifically to a method, system, electronic equipment and medium for obtaining chamfer dimensions of a lithium battery coating gasket. Background Art

[0002] In the manufacture of lithium-ion battery pole pieces, the coating process is a key link. Since lithium battery slurry has the characteristics of viscoelastic fluid, it often leads to the problem of super-high edge of the coating film, resulting in defects in subsequent processes and increased scrap rate. Therefore, in actual production, it is generally diverted by adding chamfers at the outlet of the coating gasket to weaken the super-high edge phenomenon. However, due to the limitations of modeling calculation efficiency and simulation accuracy, there is currently a lack of local refined simulation modeling methods for this problem, so it is difficult to efficiently and accurately evaluate and guide gasket design. In the current existing technology, the chamfer size of the coating gasket is generally optimized based on the process engineer's own experience and repeated experiments, or a three-dimensional full model or half model of the coating die is established based on numerical methods such as finite element and finite volume, which has problems of low efficiency and poor accuracy.

[0003] Therefore, it is necessary to propose a design scheme that can replace the existing experimental method and global modeling scheme, save considerable manpower and material costs, and provide efficient and accurate guidance for the chamfer design of lithium battery coated gaskets. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present application proposes a method, system, electronic device and medium for obtaining the chamfer dimensions of a lithium battery coated gasket. The chamfer dimensions of the lithium battery coated gasket are optimized and designed based on a locally refined joint simulation model, thereby solving the problems of low efficiency and poor precision in the chamfer design of gaskets in the existing lithium battery coating process.

[0005] In a first aspect, the present application provides a method for obtaining chamfer dimensions of a lithium battery coating gasket, comprising:

[0006] Get preset size parameters;

[0007] Inputting the preset size parameters into a joint simulation model to output simulation results; the joint simulation model includes a two-dimensional model and a three-dimensional model, wherein the flow velocity distribution and coating state output by the two-dimensional model constitute the input of the three-dimensional model;

[0008] The simulation results are provided for configuring the shim chamfer dimensions of the coating die.

[0009] In some embodiments, the flow velocity distribution and coating status output by the two-dimensional model constitute the input of the three-dimensional model, including: the flow velocity distribution output by the two-dimensional model is used to determine the inlet boundary conditions of the three-dimensional model, and the coating status output by the two-dimensional model is used to verify the three-dimensional model.

[0010] In some embodiments, the method further comprises: constructing the joint simulation model based on the collected physical and chemical data of lithium battery.

[0011] The collected lithium battery physical and chemical data include:

[0012] Testing the rheological properties of fresh positive and negative electrode slurries and fitting the test results to obtain fitting parameters;

[0013] Characteristic parameters obtained by testing fresh positive and negative electrode slurries;

[0014] As well as process parameters, gasket structure parameters and coating quality monitoring data in the coating process

[0015] The step of constructing the joint simulation model based on the collected physical and chemical data of lithium batteries includes:

[0016] A two-dimensional model is established based on the collected physical and chemical data of lithium battery, and the two-dimensional model is verified by using the two-dimensional measured data and the coating state output by the two-dimensional model simulation;

[0017] A three-dimensional model is established based on the collected physical and chemical data of lithium batteries. The flow velocity distribution of the slurry output by the two-dimensional model simulation is used as the inlet boundary condition of the three-dimensional model. The three-dimensional model is verified using three-dimensional measured data, the coating thickness output by the three-dimensional model simulation, and the coating status output by the two-dimensional model simulation.

[0018] Furthermore, the establishing of the two-dimensional model and the establishing of the three-dimensional model include establishing model equations using a fluid volume method.

[0019] The verification of the two-dimensional model includes: completing the verification of the two-dimensional model when it is determined that the deviation between the coating state output by the two-dimensional model simulation and the two-dimensional measured data is less than a set first error threshold;

[0020] The verification of the three-dimensional model includes: completing the verification of the three-dimensional model when it is determined that the deviation between the coating thickness output by the three-dimensional model simulation and the three-dimensional measured data is less than a set second error threshold, and the coating thickness output by the three-dimensional model simulation is consistent with the coating state output by the two-dimensional model simulation.

[0021] In some embodiments, the inputting the preset size parameters into the joint simulation model to output the simulation results comprises: inputting the preset size parameters into the three-dimensional model of the joint simulation model, and outputting the coating thickness distribution corresponding to different gasket chamfer sizes; the preset size parameters include a plurality of different gasket chamfer sizes;

[0022] The providing of the simulation results for configuring the gasket chamfer size of the coating die head includes: selecting the gasket chamfer size by comparative analysis of the coating film thickness distribution corresponding to the different gasket chamfer sizes and applying it to configuring the coating die head.

[0023] In a second aspect, the present application provides an electronic device comprising a processor and a storage device, wherein the storage device is suitable for storing a plurality of program codes, and the program codes are suitable for being loaded and run by the processor to execute the above-mentioned method for obtaining the chamfer size of a lithium battery coating gasket.

[0024] In a third aspect, the present application provides a lithium battery coating system, comprising the above-mentioned electronic device and a coating die, wherein a coating gasket is arranged between an upper die and a lower die of the coating die, and a chamfer is added at the outlet of the coating gasket, wherein the size of the chamfer is configured based on the simulation results.

[0025] In a fourth aspect, the present application provides a computer-readable storage medium storing a plurality of program codes, wherein the program codes are suitable for being loaded and run by a processor to execute the above-mentioned method for obtaining the chamfer size of a lithium battery coating gasket.

[0026] The above one or more technical solutions of the present application have at least one or more of the following beneficial effects:

[0027] In the technical solution of the present application, the preset size parameters are input into the joint simulation model to determine the chamfer size of the gasket used for the coating die head by the simulation results output; the joint simulation model includes a two-dimensional model and a three-dimensional model, wherein the flow velocity distribution and coating state output by the two-dimensional model constitute the input of the three-dimensional model. The present application performs simulation through a joint simulation model composed of a two-dimensional model and a three-dimensional model, realizes the complementary advantages of the two, and gives full play to the advantages of fast calculation, high precision and parallelism of the joint simulation, which can replace the existing test method and global modeling scheme, save considerable manpower and material costs, and provide efficient and accurate guidance for the design of the gasket chamfer. The gasket chamfer size obtained based on the method of the present application is applied to the coating die head, which can make the coating more uniform during extrusion, so that the edge of the produced pole piece is effectively thinned to achieve the problem of removing the thick edge, optimize the effect of the coating process, so as to ensure that the capacity and other indicators of the lithium battery of the pole piece are consistent, effectively slow down the decay rate of the lithium battery storage capacity, thereby increasing the service life of the lithium battery, and can greatly reduce the scrapping of the pole piece, thereby reducing the investment in coating production and effectively saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The disclosure of the present application will become more easily understood with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present application. In addition, similar numbers in the drawings are used to represent similar components, among which:

[0029] Figure 1 This is a schematic flow chart of the main steps of a method for obtaining chamfer dimensions of a lithium battery coating gasket of the present application;

[0030] Figure 2 It is a schematic diagram of the composition structure of a lithium battery coating process device of the present application;

[0031] Figure 3 This application is based on Figure 2 Schematic diagram of the slit-type lithium battery coating process of the lithium battery coating process device shown;

[0032] Figure 4 is based on Figure 2 A schematic diagram of the modeling area of ​​the two-dimensional model of the lithium battery coating process device structure shown;

[0033] Figure 5 is based on Figure 2 A schematic diagram of the modeling area of ​​the three-dimensional model of the lithium battery coating process device structure shown;

[0034] Figure 6 It is a two-dimensional slice simulation schematic diagram corresponding to the two-dimensional model in the joint simulation model of the present application;

[0035] Figure 7 is based on Figure 6 The schematic diagram of simulation output results of the two-dimensional slice simulation is shown;

[0036] Figure 8 is a three-dimensional simulation schematic diagram of a three-dimensional model in the joint simulation model of the present application;

[0037] Fig. 9 It uses different symmetric boundary positions to input the three-dimensional model to obtain different coating thickness distribution curve comparison diagrams;

[0038] Fig.10 It is a comparison chart of using different chamfer sizes to input the 3D model to obtain different simulation output results;

[0039] Fig.11 It is a flowchart of a specific implementation method of determining the optimal chamfer size of the present application. DETAILED DESCRIPTION

[0040] Some embodiments of the present application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application and are not intended to limit the protection scope of the present application.

[0041] In the description of the present application, "module" and "processor" may include hardware, software or a combination of the two. A module may include hardware circuits, various suitable sensors, communication ports, and memories, and may also include software parts, such as program codes, or a combination of software and hardware. The processor may be a central processing unit, a microprocessor, an image processor, a digital signal processor, or any other suitable processor. The processor has data and / or signal processing functions. The processor may be implemented in software, hardware, or a combination of the two. The term "A and / or B" means all possible combinations of A and B, such as just A, just B, or A and B. The term "at least one A or B" or "at least one of A and B" has a similar meaning to "A and / or B" and may include just A, just B, or A and B. The singular terms "one" and "the" may also include plural forms.

[0042] It should be understood that the description of the orientation in the specification and claims and the drawings of the present application, such as the orientation or positional relationship indicated by the upper, lower, left, right, etc., is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The terms "first", "second", etc. in the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0043] In the existing lithium battery coating process design scheme, when adding chamfers at the outlet of lithium battery coating gaskets, it is generally necessary to rely on the process engineer's own experience and repeated experiments to optimize the gasket chamfer size, or to provide guidance on the gasket chamfer design size by establishing a three-dimensional full model or half model of the coating die head. However, the computational cost of establishing a three-dimensional full model or half model is too high. Due to time and resource constraints, it is difficult to provide efficient and accurate guidance on the gasket chamfer design. In addition, since the effects of feeding, uniform pressure and other links on chamfer diversion in actual applications are not direct or obvious, complete modeling of these two links will increase the difficulty of computational convergence and resource allocation burden of simulation work.

[0044] To this end, the lithium battery coated gasket chamfer size acquisition method proposed in this application uses a local refined joint modeling and simulation method to optimize the gasket chamfer size design when adding a chamfer at the lithium battery coated gasket outlet. It can efficiently and accurately calculate the impact of different gasket chamfer designs on the coating edge thickness distribution, and then determine the optimal chamfer size. Specifically, this local refined joint modeling and simulation method can achieve complementary advantages of the two through two-dimensional and three-dimensional model joint simulation, and give play to the advantages of fast joint simulation calculation, high accuracy, and parallelization. It can replace the existing test method and global modeling scheme, save considerable manpower and material costs, and provide efficient and accurate guidance for gasket chamfer design.

[0045] The specific implementation methods of the present application are further described in detail below in conjunction with the drawings and examples.

[0046] See attached Figure 1 The present embodiment provides a method for obtaining the chamfer size of a lithium battery coating gasket, which mainly includes the following steps S11 to S13.

[0047] Step S11: obtaining preset size parameters;

[0048] Specifically, in this embodiment, the preset size parameters include a plurality of different gasket chamfer sizes. In practical applications, the preset size parameters may be a plurality of different gasket chamfer sizes pre-selected by process engineers based on their own experience, such as 2mm×2mm, 1.5mm×1.5mm, 1mm×1mm, etc. It should be understood that the chamfer size in this embodiment can be represented by b×c, where b and c represent the lengths of the right angle sides in two different directions of the chamfer, respectively.

[0049] Step S12: inputting the preset size parameters into a joint simulation model to output simulation results; the joint simulation model includes a two-dimensional model and a three-dimensional model, wherein the flow velocity distribution and coating state output by the two-dimensional model constitute the input of the three-dimensional model;

[0050] Specifically in this embodiment, before this step, it also includes a step of constructing the joint simulation model based on the collected lithium battery physical and chemical data. The collected lithium battery physical and chemical data mainly include characteristic parameters obtained by physical and chemical testing of lithium battery slurry, as well as collected coating process parameters, gasket structure parameters and coating quality monitoring data of the same batch, etc., wherein the gasket structure parameters can specifically adopt the preset size parameters. Specifically: the joint simulation model constructed in this embodiment is a local refined simulation model, including a two-dimensional model and a three-dimensional model, wherein the flow velocity distribution and coating state output by the two-dimensional model constitute the input of the three-dimensional model. Specifically: the simulation results output by the two-dimensional model may at least include flow velocity distribution and coating state, the flow velocity distribution output by the two-dimensional model can be used to determine the inlet boundary conditions of the three-dimensional model, and the coating state output by the two-dimensional model can be used to verify the three-dimensional model. This application takes advantage of the high precision of the two-dimensional model, and uses the output of the two-dimensional model to guide the modeling of the three-dimensional model, thereby improving the modeling accuracy of the three-dimensional model; in addition, the two-dimensional model can further compress the scale of the three-dimensional model modeling, and the flow velocity information in the simulation output of the two-dimensional model is input into the three-dimensional model, which can reduce the sensitivity of the three-dimensional model to the inlet boundary.

[0051] In a specific embodiment, the construction of the joint simulation model based on the collected physical and chemical data of lithium batteries specifically includes: establishing a two-dimensional model based on the collected physical and chemical data of lithium batteries, and verifying the two-dimensional model using the two-dimensional measured data and the coating status output by the two-dimensional model simulation; establishing a three-dimensional model based on the collected physical and chemical data of lithium batteries, using the flow velocity distribution of the slurry output by the two-dimensional model simulation as the inlet boundary condition of the three-dimensional model, and verifying the three-dimensional model using the three-dimensional measured data, the coating thickness output by the three-dimensional model simulation, and the coating status output by the two-dimensional model simulation.

[0052] Further, the verification of the two-dimensional model includes: completing the verification of the two-dimensional model when it is determined that the deviation between the coating state output by the two-dimensional model simulation and the two-dimensional measured data is less than a set first error threshold; the verification of the three-dimensional model includes: completing the verification of the three-dimensional model when it is determined that the deviation between the coating thickness output by the three-dimensional model simulation and the three-dimensional measured data is less than a set second error threshold, and the coating thickness output by the three-dimensional model simulation is consistent with the coating state output by the two-dimensional model simulation. It can be understood that the above-mentioned two-dimensional measured data and three-dimensional measured data can be understood as actual measurement data corresponding to the two-dimensional model and the three-dimensional model simulation output, respectively, for example, the two-dimensional model simulation output has a flow velocity distribution, and the two-dimensional measured data correspondingly includes the actually measured flow velocity distribution, and the three-dimensional model simulation output has a coating thickness, and the three-dimensional measured data correspondingly includes the actually measured coating thickness.

[0053] For example, this embodiment is based on Figure 2 The overall structure of the lithium battery coating process device shown in Figure 3 The local refined two-dimensional model and three-dimensional model are constructed based on the slit lithium battery coating process shown in FIG. Figure 4 and Figure 5 The dotted boxes in the figure are the modeling area and partial enlarged view of the two-dimensional model and the modeling area and partial enlarged view of the three-dimensional model. Figure 2-Figure 5 As shown, the lithium battery coating process device mainly includes a coating die head and a feed port. A coating gasket is arranged between the upper die head and the lower die head of the coating die head. The upper die head and the lower die head contact the back roller through the upper die lip and the lower die lip respectively. In this application, a local area including the location of the upper die lip and the lower die lip is selected for two-dimensional modeling. At the same time, in order to realize the simulation of the chamfer area on the coating gasket, three-dimensional modeling is jointly performed in the two-dimensional modeling area. It should be understood that Figure 2 The overall structure diagram of the lithium battery coating process device shown is only an exemplary structure. Based on the same principle, the method provided in the embodiment of the present application can also be locally modeled based on other specific coating die head structure types.

[0054] Step S13: providing the simulation results for configuring the chamfer dimensions of the gasket of the coating die;

[0055] In a specific implementation manner, the step S12 of inputting the preset size parameters into the joint simulation model to output the simulation results specifically includes: inputting the preset size parameters into the three-dimensional model of the joint simulation model, and outputting the coating thickness distribution corresponding to different gasket chamfer sizes; the preset size parameters include a plurality of different gasket chamfer sizes;

[0056] Correspondingly, the step S13 of providing the simulation results for configuring the gasket chamfer size of the coating die head specifically includes: selecting the gasket chamfer size by comparing and analyzing the coating film thickness distribution corresponding to the different gasket chamfer sizes and applying it to configure the coating die head.

[0057] It is understandable that by comparing and analyzing the coating thickness distribution corresponding to different gasket chamfer sizes output by the three-dimensional model, the optimal gasket chamfer size suitable for the current coating process can be selected. Based on the selected gasket chamfer size, by adding a chamfer at the outlet of the coating die head gasket to perform diversion, the phenomenon of super-high edge of the coating film in the coating process can be weakened.

[0058] Based on the above step S12, the process of collecting lithium battery physical and chemical data by using the same batch of fresh positive and negative electrode slurries as physical and chemical test objects may specifically include the following contents:

[0059] (1) Testing the rheological properties of fresh positive and negative electrode slurries and fitting the test results to obtain fitting parameters;

[0060] Specifically in this embodiment, the test results are fitted according to a non-Newtonian fluid model, such as a Kalman constitutive model (Carreau model), to obtain fitting parameters. The specific form of the Carreau model is as follows:

[0061]

[0062] Where: η is the dynamic viscosity; η0 is the zero shear viscosity; η∞ is the infinite shear viscosity; λ is the relaxation time; γ is the shear rate; a and n are dimensionless parameters, usually determined experimentally.

[0063] The fitting parameters obtained in this embodiment are specifically shown in Table 1 below:

[0064] Serial number parameter symbol unit 1 Slurry rheology μ-γ \ 2 Zero shear viscosity η0 Pa·s 3 Infinite shear viscosity η∞ Pa·s 4 Relaxation time λ s 5 Non-Newtonian Index n \ 6 Characteristic parameters a \

[0065] (2) Testing fresh positive and negative electrode slurries from the same batch to obtain characteristic parameters;

[0066] In this embodiment, the characteristic parameters that can be obtained through physical and chemical testing are specifically shown in Table 2 below:

[0067] Serial number parameter symbol unit 7 Solid content ζ ％ 8 Surface tension σ N / m 9 Contact Angle-Carbon Coated Aluminum Foil θ1 deg 10 Contact Angle-Die Head θ2 deg 11 Slurry density ρv <![CDATA[kg / m 3 ]]>

[0068] (3) Collect process parameters, gasket structure parameters and coating quality monitoring data in the same batch of coating processes.

[0069] Specifically, in this embodiment, the collected process parameters, gasket structure parameters and coating quality monitoring data are shown in Table 3 below:

[0070] Serial number parameter symbol unit 12 Gasket thickness t mm 13 Opening width w mm 14 Slit length l mm 15 Chamfer specifications b*c mm*mm 16 Die slit width LS mm 17 Coating gap height hg mm 18 Foil conveying speed Vsub m / s 19 Slurry feeding speed Vslu m / s 2O Area Density ρs mg / cm^2

[0071] Furthermore, the construction of a joint simulation model based on the collected physical and chemical data of lithium batteries specifically includes the following contents:

[0072] (1) establishing a two-dimensional model based on the collected physical and chemical data of lithium batteries, and verifying the two-dimensional model using simulation output and two-dimensional measured data;

[0073] Specifically, in this embodiment, based on the data of numbers 16 to 20 in Table 1, Table 2 and Table 3, the volume of fluid (VOF) method is used to establish the model equation of the two-dimensional model. For details, see Figure 6The schematic diagram of the two-dimensional slice simulation is shown in the figure. The slurry volume fractions 0 to 1 shown in the figure can correspond to different positions of the slit. The simulation output of the two-dimensional model includes the flow velocity distribution curve of the slurry at different positions of the slit and the coating state on the foil. The coating state can be understood as dry film thickness or wet film thickness. For details, please refer to Figure 7 As shown. The coating state output by the two-dimensional model simulation is compared with the two-dimensional measured data for calibration to achieve continuous optimization of the model, until the deviation between the coating state and the measured data is less than the set first error threshold to complete the model verification, for example, the first error threshold is set to 0.1. The flow velocity distribution and coating state of the slurry at different positions in the slit output by the two-dimensional model simulation that has completed the model verification can be used for the three-dimensional model.

[0074] (2) A three-dimensional model is established based on the collected physical and chemical data of lithium batteries, and the flow velocity distribution of the slurry output by the two-dimensional model is used as the inlet boundary condition of the three-dimensional model. The three-dimensional model is verified by using the simulation output of the three-dimensional model, the three-dimensional measured data and the simulation output of the two-dimensional model.

[0075] Specifically, in this embodiment, based on all the data in Table 1, Table 2 and Table 3, the volume of fluid method (VOF) is used to establish the model equation of the three-dimensional model. For details, see Figure 8 The schematic diagram of the three-dimensional model simulation is shown; by using the velocity distribution of the slurry output by the two-dimensional model as the inlet boundary condition of the three-dimensional model, and then setting the symmetrical boundary position, the accuracy and calculation efficiency of the three-dimensional model can be effectively improved. Specifically in this embodiment, the velocity distribution of the slurry output by the two-dimensional model is used as the inlet boundary condition of the three-dimensional model, and a sensitivity analysis is performed on the symmetrical boundary position, and then the appropriate symmetrical boundary position can be determined. Subsequently, the three-dimensional model is calibrated using the three-dimensional measured data and the simulation data output by the two-dimensional model to achieve continuous optimization of the model until the deviation is less than the set second error threshold (for example, 10%), and the calibrated three-dimensional model can be used for simulation calculations of different gasket chamfer designs.

[0076] It should be noted that, since the lateral dimension of the coating process is much larger than other directions, and the flow pattern is simple and the flow is stable, the symmetric boundary position does not have to coincide with the geometric symmetry plane. It only needs to be selected far enough away from the diversion area to ensure that it does not affect the diversion. In this embodiment, the symmetric boundary position is set according to the degree of proximity to the chamfer area (or diversion area), and the preferred symmetric boundary position with the minimum calculation amount under the premise of ensuring the rationality of the calculation is selected through sensitivity analysis. For example, Fig. 9As shown, the velocity distribution of the slurry output by the two-dimensional model is used as the inlet boundary condition of the three-dimensional model. Different symmetric boundary positions will correspond to different coating thickness distribution curves. For example, "symmetric boundary position + 0mm" is used as the initial working condition, and the remaining working conditions are increased by 5mm on the basis of the initial working condition. By analyzing the corresponding coating thickness distribution curves under various working conditions, it can be seen that the dry film thickness distribution curves corresponding to the symmetric boundary position + 10mm and the symmetric boundary position + 15mm overlap. At this time, it can be considered that in the example, any symmetric boundary is greater than the distance between the chamfer area and the symmetric boundary position + 10mm working condition. The selection of the symmetric boundary will not have an adverse effect on the model calculation results. Therefore, the subsequent calculations refer to the setting of the symmetric boundary position + 10mm working condition.

[0077] Furthermore, the present application specifically adopts the volume of fluid (VOF) method to establish a two-dimensional model and a three-dimensional model, wherein the VOF model equation is as follows:

[0078]

[0079] Among them, in formula (1) and (2), ρ, μ and u are the average density, average viscosity and velocity of the slurry and air phases respectively, p, τ and g represent pressure, shear stress and gravitational acceleration respectively, and Fs is the momentum source term under the action of surface tension to improve the accuracy and applicability of the model. In formula (3), α slurry and α air are the volume fractions of slurry and air, respectively, slurry = 0 is filled with air phase, slurry =1 is filled with slurry phase, and the other 0<α slurry The grid with a value of <1 contains the free interface between air and slurry, which mainly includes the upper and lower menisci of the coating droplet during extrusion coating, the diversion liquid surface at the chamfer, and the side of the liquid film.

[0080] Based on the above step S12, in a specific implementation manner, taking the multiple preset size parameters specifically including chamfer size A and chamfer size B as an example, the details can be seen in the attached Fig.10 The chamfer size A and the chamfer size B are respectively input into the three-dimensional model in the joint simulation model, and the coating thickness distribution output by the three-dimensional model simulation is analyzed and compared to find the best one, and then determine that the chamfer size B can obtain the best diversion effect matching the current process.

[0081] Furthermore, the present application also provides a specific implementation method to introduce in detail the process of the lithium battery coating gasket chamfer size acquisition method of the above steps S11 to S13, as shown in the following example. Fig.11As shown, the process includes the following steps S1 to S7.

[0082] Step S1: testing the rheological properties of fresh positive and negative electrode slurries;

[0083] Step S2: testing other characteristic parameters of fresh positive and negative electrode slurries;

[0084] Step S3: Collecting process parameters, gasket structure parameters and coating quality monitoring data of the same batch;

[0085] Step S4: 2D model simulation calculation process, specifically including: establishing a 2D coating simulation model, inputting collection parameters, outputting calculation results, verifying whether the simulated and measured film thicknesses meet the preset error threshold, if not, returning to re-modeling, if satisfied, outputting the coating status and the slurry flow rate distribution in the slit, for the construction and verification of the 3D model.

[0086] Step S5: 3D model simulation calculation process, specifically including: establishing a 3D local model for coating simulation, converting the 2D flow velocity distribution into 3D as the entry condition, selecting a suitable symmetry plane position through sensitivity analysis, outputting the calculation result, verifying whether the simulated and measured film thicknesses meet the preset error threshold, if not, returning to remodeling, if yes, further verifying whether the 3D simulation coating state is consistent with the 2D simulation, if not, returning to remodeling, if consistent, entering step S6;

[0087] Step S6: calculating the edge coating thickness distribution under different chamfered gaskets;

[0088] Step S7: Analyze the gasket chamfer design effect and optimize it.

[0089] It can be seen that the above specific implementation method can obtain the optimal chamfer size of the gasket, which can be used to add a chamfer at the outlet of the coating die gasket according to the size, thereby weakening the over-height phenomenon of the coating edge, thereby achieving the effect of optimizing the coating process.

[0090] Furthermore, the present application also provides a lithium battery coating process device.

[0091] In an embodiment of a lithium battery coating process device of the present application, the device mainly includes a coating die head, a coating gasket is arranged between the upper die head and the lower die head of the coating die head, and a chamfer is added at the outlet of the coating gasket. The chamfer size of the chamfer is determined according to the lithium battery coating gasket chamfer size acquisition method of the above-mentioned method embodiment.

[0092] Furthermore, the present application also provides an electronic device.

[0093] In an embodiment of an electronic device according to the present application, the electronic device mainly includes a processor and a storage device, the storage device can be configured to store a program for executing the method for obtaining the chamfer size of a lithium battery coated gasket in the above method embodiment, and the processor can be configured to execute the program in the storage device, which includes but is not limited to executing the program for obtaining the chamfer size of a lithium battery coated gasket in the above method embodiment. For ease of explanation, only the parts related to the embodiments of the present application are shown. For specific technical details not disclosed, please refer to the method part of the embodiments of the present application.

[0094] In the embodiment of the present application, the electronic device may be a control device device formed by various electronic devices. In some possible implementations, the electronic device may include multiple storage devices and multiple processors. The program for executing the method for obtaining the chamfer size of the lithium-ion coated gasket of the above method embodiment can be divided into multiple subprograms, and each subprogram can be loaded and run by the processor to execute different steps of the method for obtaining the chamfer size of the lithium-ion coated gasket of the above method embodiment. Specifically, each subprogram can be stored in different storage devices, and each processor can be configured to execute programs in one or more storage devices to jointly implement the method for obtaining the chamfer size of the lithium-ion coated gasket of the above method embodiment, that is, each processor executes different steps of the method for obtaining the chamfer size of the lithium-ion coated gasket of the above method embodiment, to jointly implement the method for obtaining the chamfer size of the lithium-ion coated gasket of the above method embodiment.

[0095] The above-mentioned multiple processors may be processors deployed on the same device. For example, the above-mentioned electronic device may be a high-performance device composed of multiple processors, and the above-mentioned multiple processors may be processors configured on the high-performance device.

[0096] Furthermore, the present application also provides a lithium battery coating system, comprising the above-mentioned electronic device and a coating die, wherein a coating gasket is arranged between the upper die and the lower die of the coating die, and a chamfer is added at the outlet of the coating gasket, wherein the size of the chamfer is configured based on the simulation results.

[0097] Furthermore, the present application also provides a computer-readable storage medium.

[0098] In a computer-readable storage medium embodiment according to the present application, the computer-readable storage medium can be configured to store a program for executing the above-mentioned method embodiment of the lithium-ion coated gasket chamfer size acquisition method, and the program can be loaded and run by the processor to implement the above-mentioned lithium-ion coated gasket chamfer size acquisition method. For ease of explanation, only the parts related to the embodiment of the present application are shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present application. The computer-readable storage medium can be a storage device formed by various electronic devices. Optionally, the computer-readable storage medium in the embodiment of the present application is a non-temporary computer-readable storage medium.

[0099] So far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. A method for obtaining chamfer dimensions of a lithium battery coating gasket, characterized in that: include: Get preset size parameters; Inputting the preset size parameters into the joint simulation model to output simulation results; The joint simulation model includes a two-dimensional model and a three-dimensional model, wherein the flow velocity distribution and coating state output by the two-dimensional model constitute the input of the three-dimensional model; The simulation results are provided for configuring the shim chamfer dimensions of the coating die.

2. The method according to claim 1, characterized in that: The flow velocity distribution and coating state output by the two-dimensional model constitute the input of the three-dimensional model, including: The flow velocity distribution output by the two-dimensional model is used to determine the inlet boundary conditions of the three-dimensional model, and the coating state output by the two-dimensional model is used to verify the three-dimensional model.

3. The method according to claim 1, characterized in that Also includes: The joint simulation model is constructed based on the collected physical and chemical data of lithium batteries.

4. The method according to claim 3, characterized in that: The collected lithium battery physical and chemical data include: Testing the rheological properties of fresh positive and negative electrode slurries and fitting the test results to obtain fitting parameters; Characteristic parameters obtained by testing fresh positive and negative electrode slurries; As well as process parameters in the coating process, gasket structure parameters and coating quality monitoring data.

5. The method according to claim 3, characterized in that: The step of constructing the joint simulation model based on the collected physical and chemical data of lithium batteries includes: A two-dimensional model is established based on the collected physical and chemical data of lithium battery, and the two-dimensional model is verified by using the two-dimensional measured data and the coating state output by the two-dimensional model simulation; A three-dimensional model is established based on the collected physical and chemical data of lithium batteries. The flow velocity distribution of the slurry output by the two-dimensional model simulation is used as the inlet boundary condition of the three-dimensional model. The three-dimensional model is verified using three-dimensional measured data, the coating thickness output by the three-dimensional model simulation, and the coating status output by the two-dimensional model simulation.

6. The method according to claim 5, characterized in that: The verification of the two-dimensional model includes: completing the verification of the two-dimensional model when it is determined that the deviation between the coating state output by the two-dimensional model simulation and the two-dimensional measured data is less than a set first error threshold; The verification of the three-dimensional model includes: completing the verification of the three-dimensional model when it is determined that the deviation between the coating thickness output by the three-dimensional model simulation and the three-dimensional measured data is less than a set second error threshold, and the coating thickness output by the three-dimensional model simulation is consistent with the coating state output by the two-dimensional model simulation.

7. The method according to claim 1, characterized in that: The step of inputting the preset size parameters into the joint simulation model to output the simulation results comprises: inputting the preset size parameters into the three-dimensional model of the joint simulation model, and outputting the coating thickness distribution corresponding to different gasket chamfer sizes; the preset size parameters include a plurality of different gasket chamfer sizes; The providing of the simulation results for configuring the gasket chamfer size of the coating die head includes: selecting the gasket chamfer size by comparative analysis of the coating film thickness distribution corresponding to the different gasket chamfer sizes and applying it to configuring the coating die head.

8. An electronic device comprising a processor and a storage device, wherein the storage device is suitable for storing a plurality of program codes, characterized in that: The program code is suitable for being loaded and run by the processor to execute the method for obtaining the chamfer size of a lithium battery coating gasket as described in any one of claims 1-7.

9. A lithium battery coating system, characterized in that: include: The electronic device according to claim 8; as well as A coating die head is provided with a coating gasket between an upper die head and a lower die head of the coating die head, and a chamfer is added at an outlet of the coating gasket, wherein the size of the chamfer is configured based on the simulation result.

10. A computer-readable storage medium storing a plurality of program codes, wherein the program codes are suitable for being loaded and run by a processor to execute the method for obtaining the chamfer size of a lithium battery coating gasket as described in any one of claims 1 to 7.

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