Battery internal uniformity analysis method and system, electronic equipment and storage medium

Abstract

The invention provides a battery internal uniformity analysis method and system, electronic equipment and a storage medium, and relates to the technical field of lithium ion batteries, the method comprises: constructing a three-dimensional multi-physics field coupling model of a target battery, the three-dimensional multi-physics field coupling model comprising a three-dimensional geometric sub-model, an electrochemical reaction sub-model and a thermal field sub-model; a plurality of tab design schemes are set, tab parameters of the tab design schemes are different, and the tab parameters at least comprise the number of tabs, the width of the tabs and the positions of the tabs; simulation analysis is conducted according to the three-dimensional multi-physics field coupling model and the tab design scheme, a uniformity analysis result is obtained, and simulation analysis at least comprises discharge curve analysis, direct current internal resistance test analysis, current distribution and current density analysis, current collector ohmic loss analysis, active material overpotential analysis and battery temperature distribution analysis. The method is based on all-parameter uniformity simulation analysis, and spatial distribution of key parameters in the battery can be quantified.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium-ion batteries, and in particular to a method, system, electronic equipment and storage medium for analyzing internal uniformity of a battery. Background Art

[0002] In the research and development of lithium-ion batteries, the uniformity of internal parameters such as current distribution, temperature distribution, polarization, and overpotential is crucial to the battery's overall performance and safety. However, traditional experimental methods have significant limitations. They can typically only measure macroscopic battery parameters (such as voltage and surface temperature), but have difficulty quantifying the uniformity of internal current density and potential distribution, and are even more unable to accurately identify local hotspots or areas of concentrated polarization.

[0003] Existing simulation technologies are mostly based on simplified models, such as one-dimensional electrochemical models or two-dimensional thermal conduction models. This leads to significant deviations between predicted results and actual scenarios, making it difficult to effectively guide battery design and optimization. Furthermore, during the design optimization phase, there is currently a lack of systematic analysis of the correlation between the number and layout of tabs and internal uniformity. As a result, design adjustments often rely on empirical judgment, which is inefficient and lacks scientific basis.

[0004] Currently, some existing technologies attempt to obtain internal physical field distribution data by implanting microsensors inside batteries. However, this approach not only compromises the integrity of the battery structure but also comes with high costs. Furthermore, single-physics simulation methods cannot fully reflect the combined impact of multi-physics coupling effects on battery internal uniformity. Therefore, accurately and directly obtaining internal physical field distribution data has become a pressing technical challenge. Summary of the Invention

[0005] In view of the above-mentioned deficiencies in the prior art, the present invention provides a battery internal uniformity analysis method, system, electronic device and storage medium, which effectively solve the problem of being unable to accurately and directly obtain the internal physical field distribution data of the battery.

[0006] In a first aspect, the present invention provides a method for analyzing internal uniformity of a battery, the method comprising: Constructing a three-dimensional multi-physics field coupling model of the target battery, wherein the three-dimensional multi-physics field coupling model includes a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model; Setting a plurality of tab design schemes, wherein the tab parameters of each tab design scheme are different, and the tab parameters include at least the number of tabs, the width of the tabs and the position of the tabs; A simulation analysis is performed based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results, wherein the simulation analysis includes at least discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, current collector ohmic loss analysis, active material overpotential analysis, and battery temperature distribution analysis.

[0007] In an optional embodiment, constructing a three-dimensional multi-physics field coupling model of the target battery includes: Constructing a three-dimensional geometric body according to the positive electrode, negative electrode, separator, and tab of the target battery, and physically defining corresponding geometric regions of the three-dimensional geometric body according to material properties to obtain the three-dimensional geometric sub-model; Defining the electrochemical reaction equation, charge transfer equation, charge diffusion equation, material conservation equation, and boundary conditions of the target battery to obtain the electrochemical reaction sub-model; Constructing the thermal field sub-model according to the Joule heat, reaction heat and natural convection heat dissipation of the target battery; The three-dimensional geometric sub-model, the electrochemical reaction sub-model and the thermal field sub-model are coupled to obtain the three-dimensional multi-physics field coupling model.

[0008] In an optional embodiment, the simulation analysis is a discharge curve analysis, and the simulation analysis performed based on the three-dimensional multi-physics field coupling model and the tab design scheme includes: Under each of the tab designs, constant current discharge simulations at different rates were performed according to the three-dimensional multi-physics field coupling model, and a transient solver was used to obtain a voltage-time curve.

[0009] In an optional embodiment, the simulation analysis is a DC internal resistance test analysis, and the simulation analysis performed according to the three-dimensional multi-physics field coupling model and the tab design scheme includes: Under each of the tab designs, constant current discharge is performed for a preset time at a preset battery state of charge according to the three-dimensional multi-physics field coupling model, and the DC resistance is calculated based on the transient voltage response.

[0010] In an optional embodiment, the simulation analysis is a current distribution and current density analysis, and the simulation analysis performed based on the three-dimensional multi-physics field coupling model and the tab design scheme includes: Under each of the tab design schemes, the current transmission path is simulated according to the three-dimensional multi-physics field coupling model, and a current distribution line diagram and a current density distribution cloud diagram are generated according to the current transmission path.

[0011] In an optional embodiment, the simulation analysis is a current collector ohmic loss analysis, and the simulation analysis performed according to the three-dimensional multi-physics field coupling model and the tab design scheme includes: Under each of the tab design schemes, potential distribution data of the positive and negative electrodes of the target battery are extracted according to the three-dimensional multi-physics field coupling model, and the maximum potential difference is calculated according to the potential distribution data.

[0012] In an optional embodiment, the simulation analysis is an active material overpotential analysis, and the simulation analysis performed according to the three-dimensional multi-physics field coupling model and the tab design scheme includes: Under each of the tab designs, the overpotentials of lithium ion insertion and extraction reactions are calculated at the positive and negative active materials of the target battery according to the three-dimensional multi-physics field coupling model to obtain positive and negative electrode overpotential distribution cloud maps.

[0013] In a second aspect, the present invention provides a battery internal uniformity analysis system, the system comprising: A model building module, used to build a three-dimensional multi-physics field coupling model of the target battery, wherein the three-dimensional multi-physics field coupling model couples a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model; A tab design module, configured to set a plurality of tab design schemes, wherein the tab parameters of each tab design scheme are different, and the tab parameters include at least the number of tabs, the width of the tabs, and the position of the tabs; A simulation analysis module is used to perform simulation analysis based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results. The simulation analysis includes at least discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, collector ohmic loss analysis, active material overpotential analysis and battery temperature distribution analysis.

[0014] In a third aspect, the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the battery internal uniformity analysis method as described in the first aspect of the present invention.

[0015] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the battery internal uniformity analysis method as described in the first aspect of the present invention.

[0016] The battery internal uniformity analysis method, system, electronic device and storage medium provided by the present invention, through high-precision three-dimensional modeling and dynamic visualization technology, based on full-parameter uniformity simulation analysis, quantifies the spatial distribution of key parameters such as current density, temperature, polarization and overpotential inside the battery, fills the gap in experimental data, and provides data support for uniformity optimization. The multi-physics field dynamic coupling model integrates electrochemical-thermal-current fields, accurately simulates the interactive effects of tab parameter changes on multi-physics fields, improves simulation accuracy, and reveals the key role of tab parameters on uniformity. At the same time, by replacing experimental trial and error with simulation, the development cycle is greatly shortened, and the cost of single design verification is significantly reduced, achieving a dual innovation in design efficiency and cost-effectiveness, providing an efficient and economical solution for the development of high-performance batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a first schematic diagram of the process of the battery internal uniformity analysis method provided by an embodiment of the present invention; Figure 2 This is a second schematic diagram of the process of the battery internal uniformity analysis method provided by an embodiment of the present invention; Figure 3 1C constant current discharge simulation schematic diagram of different tab design schemes in an embodiment of the present invention; Figure 4 3C constant current discharge simulation schematic diagram of different tab design schemes in an embodiment of the present invention; Figure 5 2 is a schematic diagram of DC internal resistance test analysis of different tab designs according to an embodiment of the present invention; Figure 6 1 is a current distribution diagram of different tab designs in an embodiment of the present invention; Figure 7 1 is a current density distribution cloud diagram of different tab design schemes in an embodiment of the present invention; Figure 8 1 is a cloud diagram of the positive electrode potential distribution of different tab designs in an embodiment of the present invention; Figure 9 1 is a cloud diagram of the negative electrode potential distribution of different tab designs in an embodiment of the present invention; Figure 10 1 is a cloud diagram of the positive and negative electrode overpotential distribution of different tab designs in an embodiment of the present invention; Figure 111 is a temperature distribution cloud diagram of batteries with different tab designs according to an embodiment of the present invention; Figure 12 Schematic diagram of the structure of a battery internal uniformity analysis system provided by an embodiment of the present invention; Figure 13 It is a structural diagram of an electronic device provided by an embodiment of the present invention.

[0019] Description of main component symbols: 200. Battery internal uniformity analysis system; 210. Model building module; 220. Tab design module; 230. Simulation analysis module; 300. Electronic device; 310. Processor; 320. Communication interface; 330. Memory; 340. Communication bus. DETAILED DESCRIPTION

[0020] To make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be further clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be noted that the embodiments described are only 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 making creative work are within the scope of protection of the present invention.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present invention. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0023] Currently, the uniformity analysis of internal battery parameters such as current distribution, temperature distribution, polarization, and overpotential has a crucial impact on the overall performance and safety of the battery. Existing simulation technologies are mostly based on simplified models, such as one-dimensional electrochemical models or two-dimensional heat conduction models. This leads to a large deviation between the predicted results and the actual scenario, making it difficult to effectively guide battery design and optimization. Furthermore, during the design optimization phase, there is currently a lack of systematic analysis of the correlation between the number and layout of tabs and internal uniformity. Therefore, design adjustments often rely on empirical judgment, which is inefficient and lacks scientific basis.

[0024] Some existing technologies attempt to obtain internal physical field distribution data by implanting microsensors within batteries. However, this approach not only compromises the integrity of the battery structure but also comes with high costs. Furthermore, single-physics simulation methods cannot fully reflect the combined impact of multi-physics coupling on internal battery uniformity. Therefore, accurately and directly obtaining internal physical field distribution data has become a pressing technical challenge.

[0025] Example 1 The embodiment of the present invention provides a method for analyzing uniformity inside a battery, which effectively solves the problem of being unable to accurately and directly obtain physical field distribution data inside the battery. Figure 1 FIG. 1 is a first schematic diagram of a method for analyzing internal uniformity of a battery provided by an embodiment of the present invention. Figure 1 As shown, the method includes the following steps: S100, constructing a three-dimensional multi-physics field coupling model of the target battery, wherein the three-dimensional multi-physics field coupling model includes a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model.

[0026] In an embodiment of the present invention, the target battery is a lithium-ion battery. Figure 2 This is a second schematic diagram of the process of the battery internal uniformity analysis method provided by an embodiment of the present invention. Figure 2 As shown in Figure 2, the construction of the three-dimensional multi-physics field coupling model includes the following steps: S110. Construct a three-dimensional geometric body according to the positive electrode, negative electrode, separator, and tab of the target battery, and physically define corresponding geometric regions of the three-dimensional geometric body according to material properties to obtain a three-dimensional geometric sub-model.

[0027] In this embodiment of the present invention, to accurately simulate the internal multi-physics field distribution of the target battery, a 3D geometric sub-model containing the positive electrode, negative electrode, separator, and tab is constructed. The 3D geometry, including the positive electrode current collector, positive electrode active coating, negative electrode current collector, negative electrode active coating, separator, and tab, is created using CAD tools within the simulation software.

[0028] The positive electrode current collector can be made of metal material, and a thin sheet geometry is created through CAD tools, and its thickness and size are defined. The positive electrode active coating creates an active material layer on the surface of the positive electrode current collector, and its thickness and porosity are defined. The negative electrode current collector is made of metal material, and a thin sheet geometry that matches the size of the positive electrode current collector is created through CAD tools. The negative electrode active coating creates an active material layer on the surface of the negative electrode current collector, and its thickness and porosity are defined. The diaphragm modeling is done by creating a porous diaphragm layer and defining its thickness, porosity and ion conductivity. The tab modeling is done by creating a tab geometry and fitting it to the positive and negative electrode current collectors through Boolean operations to ensure seamless connection of the contact surface. The tab material is defined as a metal material, and its thickness and size are defined. At the same time, the battery side is designed as a semi-cylindrical connection through semi-arc stretching to optimize current distribution and heat dissipation path.

[0029] In order to ensure the accuracy of the simulation, corresponding material properties can be defined for each geometric area of ​​the three-dimensional geometric body. In an embodiment of the present invention, the material of the positive electrode current collector is aluminum foil, and the properties such as electrical conductivity, thermal conductivity and density are defined. The material of the positive electrode active coating is lithium iron phosphate material, and the material properties such as electrical conductivity, ion diffusion coefficient, porosity and specific surface area are defined. The material of the negative electrode current collector is copper foil, and the properties such as electrical conductivity, thermal conductivity and density are defined. The material of the negative electrode active coating is graphite, and the material properties such as electrical conductivity, ion diffusion coefficient, porosity and specific surface area are defined. At the same time, the target battery parameters are set. In an embodiment of the present invention, the capacity of the target battery is 5Ah, the positive electrode material is lithium iron phosphate material, and the thickness is 81 um , the negative electrode material is graphite, with a thickness of 58 um , the electrolyte uses LiPF6 / EC-EMC.

[0030] S120. Define the electrochemical reaction equation, charge transfer equation, charge diffusion equation, material conservation equation, and boundary conditions of the target battery to obtain an electrochemical reaction sub-model.

[0031] In an embodiment of the present invention, an electrochemical reaction sub-model is constructed based on the quasi-two-dimensional (P2D) model of a lithium battery. By defining governing equations such as the electrochemical reaction equation, charge transfer equation, charge diffusion equation, and conservation of matter equation, as well as boundary conditions, the target battery's charge and discharge processes are simulated. The input data for the electrochemical reaction sub-model includes physical properties such as the equilibrium potential, conductivity, and diffusion coefficient of the battery material, as well as design parameters such as the porosity and electrode thickness of the target battery. By solving the governing equations, grid calculation data is extracted to obtain the distribution of the internal potential and current of the target battery.

[0032] The electrochemical reaction equation uses the Butler-Volmer equation, which quantitatively relates the current density of the electrode reaction to the overpotential and is used to describe the insertion and extraction reaction rates of lithium ions at the electrode interface. The expression of the Butler-Volmer equation is as follows:

[0033] In the above formula, i represents the current density, i 0 represents the exchange current density, reflecting the intrinsic activity of the electrode reaction, and denote the anodic transfer coefficient and the cathodic transfer coefficient, respectively, which are used to quantify the effect of potential on the activation energy barrier. R represents the gas constant, T represents the thermodynamic temperature, F represents the Faraday constant, η Indicates overpotential.

[0034] The charge transfer equation is composed of the solid-phase electron current conduction equation and the liquid-phase ion current conduction equation, which is used to control the current change inside the battery. The expression of the charge transfer equation is as follows:

[0035] In the above formula, I Indicates the internal current of the battery, represents the effective conductivity of the solid phase material, represents the solid-phase potential gradient, which drives the electrons to transport in the electrode material. represents the effective conductivity of the liquid electrolyte, represents the liquid phase potential gradient, which drives ions to transport in the electrolyte. R represents the gas constant, T represents the thermodynamic temperature, F represents the Faraday constant, represents the cation transference number, represents the activity coefficient, c l Indicates the electrolyte concentration, It represents the logarithmic gradient of electrolyte concentration and reflects the change of ion concentration.

[0036] The material conservation equation is used to describe the diffusion of lithium ions in electrode particles. The expression of the material conservation equation is as follows:

[0037] In the above formula, c represents the lithium ion concentration, r represents the electrode particle diameter, t Indicates time, Ds Represents the diffusion coefficient of lithium ions in electrode particles.

[0038] In an embodiment of the present invention, the governing equations are discretized on a three-dimensional grid using the finite element method to generate a system of algebraic equations. The nonlinear terms in the Butler-Volmer equation are solved using the Newton-Raphson numerical iteration method. Boundary conditions and initial conditions are set simultaneously, where the current input condition is a constant current applied at the tab, the voltage cutoff condition is discharge to 2.5V, and the initial battery state of charge is set to the initial lithium ion concentration distribution, thereby obtaining an electrochemical reaction sub-model.

[0039] S130. Construct a thermal field sub-model based on the Joule heat, reaction heat, and natural convection heat dissipation of the target battery.

[0040] During the charge and discharge process of lithium-ion batteries, the distribution and evolution of the thermal field are crucial to battery performance and safety. The heat sources mainly include Joule heat and reaction heat, while natural convection heat dissipation must also be considered. Joule heat is calculated based on the current density and the ohmic heating of the current collector. The calculation formula for Joule heat is as follows:

[0041] In the above formula, Q J represents Joule heat, represents the resistivity, j Represents the current density.

[0042] The reaction heat is calculated based on the entropy heat of the electrode reaction rate. The calculation formula for the reaction heat is as follows:

[0043] In the above formula, Q R represents the heat of reaction, j represents the current density, represents the entropy change of the reaction, F represents the Faraday coefficient.

[0044] Natural convection cooling simulates the heat dissipation of the target battery by setting natural convection boundary conditions and ambient temperature. The natural convection cooling boundary conditions are as follows:

[0045] In the above formula, k represents the thermal conductivity of the battery material, Represents the temperature gradient in the normal direction of the target battery surface, h represents the convective heat transfer coefficient, T Indicates the target battery surface temperature, T env Indicates the ambient temperature.

[0046] In the embodiment of the present invention, the convection heat transfer coefficient is set to 15 W / (m²·K) and the ambient temperature is set to 25°C.

[0047] In this embodiment of the present invention, a thermal field sub-model is constructed by coupling Joule heating, reaction heat, and natural convection heat dissipation to accurately simulate the thermal behavior of lithium-ion batteries during the charge and discharge process. The discharge process is simulated using a transient solver, grid calculation data is extracted, and the temperature field distribution matrix is ​​derived to generate a temperature contour map. The transient solver captures the dynamic evolution of the temperature field, while the temperature contour map intuitively displays the location and distribution of hotspots.

[0048] S140, coupling the three-dimensional geometric sub-model, the electrochemical reaction sub-model and the thermal field sub-model to obtain a three-dimensional multi-physics field coupling model.

[0049] In this embodiment of the present invention, a physical field interface is set up based on the 3D geometric sub-model, through which the electrochemical reaction sub-model and the thermal field sub-model are called. The electrochemical reaction sub-model and the thermal field sub-model are coupled through alternating iterations. At each time step, the electrochemical field is first solved, and the electrochemical field results are then passed to the thermal field sub-model. The thermal field is then solved and fed back to the electrochemical model to update the parameters of the 3D geometric sub-model.

[0050] S200 , setting a plurality of tab design schemes, wherein the tab parameters of each tab design scheme are different, and the tab parameters at least include the number of tabs, the width of the tabs, and the position of the tabs.

[0051] In an embodiment of the present invention, multiple tab design schemes can be provided, each with different tab parameter settings, and the optimal tab scheme is selected through comprehensive comparison of multiple parameters. Tab parameters include but are not limited to the number of tabs, tab width, and tab position.

[0052] In the embodiment of the present invention, the number of tabs is graded, and four different tab design schemes are set, namely Scheme A, Scheme B, Scheme C and Scheme D. Scheme A is used as the baseline design, with one pair of tabs per circle, for a total of three pairs of tabs. Scheme B increases the number of tabs by 1 / 3, for a total of four pairs of tabs. Scheme C increases the number of tabs by 2 / 3, for a total of five pairs of tabs. Scheme D doubles the number of tabs, for a total of six pairs of tabs.

[0053] Optionally, in order to analyze the marginal effect of the tab width on uniformity, a width variable group can be set based on Scheme A, and the tab width is set to ±25% of the tab width in Scheme A.

[0054] S300. Perform simulation analysis based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results. The simulation analysis at least includes discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, current collector ohmic loss analysis, active material overpotential analysis, and battery temperature distribution analysis.

[0055] In an embodiment of the present invention, if the simulation analysis is a discharge curve analysis, a constant current discharge simulation at different rates is performed based on a three-dimensional multi-physics field coupling model to simulate the voltage response within the full discharge cycle. The discharge rates are set to 1C and 3C, i.e., current 5A and current 15A, respectively. The initial battery state of charge is 100%, and the cut-off voltage is 2.5V. 1C and 3C discharge simulations are performed for Schemes A to D, respectively, and the transient solver is called to record the voltage-time curve. Figure 3 This is a schematic diagram of a 1C constant current discharge simulation in an embodiment of the present invention. Figure 4 3C constant current discharge simulation diagram in the embodiment of the present invention. Figure 3 and Figure 4 As shown in FIG, under 3C rate discharge, the polarization gradually decreases from scheme A to scheme D.

[0056] In an embodiment of the present invention, if the simulation analysis is a DC internal resistance test analysis, a short-time pulse test is performed based on the three-dimensional multi-physics field coupling model, that is, a constant current discharge is performed for a preset time at a preset battery state of charge, and the DC resistance is calculated based on the transient voltage response. Optionally, a 1C constant current discharge is performed for a preset time of 30 seconds at a preset battery state of charge of 50%, and the transient voltage response is recorded. Figure 5 2 is a schematic diagram of the DC internal resistance test analysis of different tab design schemes in the embodiment of the present invention.

[0057] The calculation formula of DC internal resistance is as follows:

[0058] In the above formula, DCR represents the DC internal resistance, Indicates the voltage difference before and after pulse discharge, I Indicates the pulse discharge current, which is set to 1C, that is, 5A.

[0059] The DC internal resistance calculation results of Scheme A to Scheme D are shown in Table 1.

[0060] Table 1. Schematic diagram of DC internal resistance of different tab designs

[0061] As shown in Table 1 above, the DC internal resistance is reduced by 9.1% from Scheme A to Scheme D.

[0062] In an embodiment of the present invention, if the simulation analysis is current distribution and current density analysis, the current transmission path is simulated according to the three-dimensional multi-physics field coupling model, and a current distribution line diagram is generated according to the current transmission path. Figure 6 The following is a schematic diagram of the current distribution line diagram of different tab design schemes in the embodiment of the present invention. The three-dimensional multi-physics field coupling model contains grid data based on the calculation results of the current transmission path. Through post-processing, the grid data distribution matrix can be rendered to generate a current density distribution cloud map. Figure 7 Schematic diagram of the current density distribution cloud diagram of different tab design schemes in the embodiment of the present invention.

[0063] By extracting the data of the current density distribution cloud map of different tab design schemes, the maximum current density, minimum current density, average current density and maximum current density difference are calculated for comparative quantitative analysis. The current density analysis results are shown in Table 2. From Scheme A to Scheme D, the current density uniformity gradually improves.

[0064] Table 2. Schematic diagram of current density analysis of different tab designs

[0065] In an embodiment of the present invention, if the simulation analysis is a current collector ohmic loss analysis, the potential distribution data of the positive and negative electrodes of the target battery are extracted according to the three-dimensional multi-physics field coupling model to generate a positive electrode potential distribution cloud map and a negative electrode potential distribution cloud map. Figure 8 is a cloud diagram of the positive electrode potential distribution of different tab designs in the embodiment of the present invention. Figure 9 1 is a cloud diagram of the negative electrode potential distribution of different tab designs in the embodiment of the present invention.

[0066] Based on the potential distribution data, the maximum potential difference was calculated and quantitatively compared for different tab designs. The maximum potential difference results for the positive current collector for different tab designs are shown in Table 3, and the maximum potential difference results for the negative current collector for different tab designs are shown in Table 4. From Schemes A to D, as the number of tabs increases, the potential distribution of the positive and negative current collectors becomes more uniform, and the ohmic loss gradually decreases.

[0067] Table 3. Schematic diagram of the maximum potential difference of the positive electrode current collector for different tab designs

[0068] Table 4. Schematic diagram of the maximum potential difference of the negative electrode current collector for different tab designs

[0069] In an embodiment of the present invention, if the simulation analysis is an active material overpotential analysis, the overpotentials of lithium ion insertion and extraction reactions are calculated at the positive and negative active materials of the target battery according to the three-dimensional multi-physics field coupling model, and a positive and negative electrode overpotential distribution cloud map is generated. Figure 10 It is a cloud diagram of the positive and negative electrode overpotential distribution of different tab design schemes in the embodiment of the present invention.

[0070] The overpotential distribution data was extracted based on the positive and negative electrode overpotential distribution cloud map, the mean and extreme values ​​were calculated, and different tab design schemes were quantitatively compared. The overpotential distribution data results of different tab design schemes are shown in Table 5. From Scheme A to Scheme D, as the number of tabs increases, there is no obvious difference in the average overpotential, and the maximum overpotential gradually decreases, which proves that the distribution is gradually more uniform.

[0071] Table 5. Schematic diagram of overpotential distribution data results for different tab designs

[0072] In an embodiment of the present invention, if the simulation analysis is a battery temperature distribution analysis, the dynamic evolution of the temperature field at the end of 3C discharge is simulated according to the thermal field sub-model in the three-dimensional multi-physics field coupling model to obtain a battery temperature distribution cloud map. Figure 11 is a cloud diagram of battery temperature distribution for different tab designs in the embodiment of the present invention, such as Figure 11 As shown, the temperature distribution of scheme D is uniform, and there is no concentrated hot spot in the tab area.

[0073] The temperature data extracted from the battery temperature distribution cloud map of different tab design schemes is shown in Table 6.

[0074] Table 6. Schematic diagram of temperature data for different tab designs

[0075] Simulation analysis of the four different tab designs above shows that with every 1 / 3 increase in the number of tabs, the DC internal resistance decreases by approximately 3%, the maximum temperature decreases by approximately 5°C, current density uniformity improves, overpotential uniformity improves, and polarization gradually decreases. Therefore, the uniformity analysis results show that as the number of tabs increases, the uniformity of various physical quantities within the battery improves, leading to improved overall performance.

[0076] As a further implementation method of the embodiment of the present invention, in order to analyze the marginal effect of the tab width on uniformity, a width variable group of ±25% of the tab width is set on the basis of Scheme A for comparison, and the variables of Schemes E and F are set to the tab width, wherein Scheme E has one pair of tabs per circle, a total of three pairs of tabs, and the tab width is 1.25 times the tab width in Scheme A; Scheme F has one pair of tabs per circle, a total of three pairs of tabs, and the tab width is 0.75 times the tab width in Scheme A. Simulation analysis was performed based on the three-dimensional multi-physics field coupling model, and the simulation results showed that the effect of the tab width change on the target battery performance was negligible, and the fluctuation of the DC internal resistance was less than 2%, thus verifying that the number of tabs is the core optimization parameter of the target battery.

[0077] The battery internal uniformity analysis method provided by the embodiments of the present invention utilizes high-precision three-dimensional modeling and dynamic visualization technology, based on full-parameter uniformity simulation analysis, to quantify the spatial distribution of key parameters such as current density, temperature, polarization, and overpotential within the battery. This fills the gap in experimental data and provides data support for uniformity optimization. The multi-physics dynamic coupling model integrates electrochemical, thermal, and current fields to accurately simulate the interactive effects of tab parameter changes on multiple physical fields, improving simulation accuracy and revealing the critical role of tab parameters in uniformity.

[0078] Example 2 Based on the same technical concept as the above embodiments, an embodiment of the present invention provides a battery internal uniformity analysis system. Figure 12 FIG. 1 is a schematic diagram of the structure of a battery internal uniformity analysis system provided by an embodiment of the present invention. Figure 12 As shown, the battery internal uniformity analysis system 200 includes: A model building module 210 is used to build a three-dimensional multi-physics field coupling model of the target battery, wherein the three-dimensional multi-physics field coupling model couples a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model; The tab design module 220 is used to set multiple tab design schemes, each tab design scheme has different tab parameters, and the tab parameters include at least the number of tabs, the tab width and the tab position; The simulation analysis module 230 is used to perform simulation analysis based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results. The simulation analysis includes at least discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, collector ohmic loss analysis, active material overpotential analysis and battery temperature distribution analysis.

[0079] The battery internal uniformity analysis system provided by the embodiment of the present invention replaces experimental trial and error with simulation, greatly shortens the development cycle, significantly reduces the cost of single design verification, achieves dual innovations in design efficiency and cost-effectiveness, and provides an efficient and economical solution for the development of high-performance batteries.

[0080] It can be understood that the implementation method of the battery internal uniformity analysis method described in the above embodiment 1 is also applicable to this embodiment and can achieve the same technical effect, so it will not be repeated here.

[0081] Example 3 Based on the same concept, an embodiment of the present invention further provides an electronic device, Figure 13 is a schematic structural diagram of an electronic device provided by an embodiment of the present invention, such as Figure 13 As shown, the electronic device 300 may include: a processor 310, a communication interface 320, a memory 330, and a communication bus 340, wherein the processor 310, the communication interface 320, and the memory 330 communicate with each other via the communication bus 340. The processor 310 may call the logic instructions in the memory 330 to execute the steps of the battery internal uniformity analysis method described in the above embodiments. For example, the steps include: S100, constructing a three-dimensional multi-physics field coupling model of the target battery, the three-dimensional multi-physics field coupling model including a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model; S200, setting a plurality of tab design schemes, wherein the tab parameters of each tab design scheme are different, and the tab parameters include at least the number of tabs, the tab width, and the tab position; S300. Perform simulation analysis based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results. The simulation analysis at least includes discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, current collector ohmic loss analysis, active material overpotential analysis, and battery temperature distribution analysis.

[0082] The processor 310 may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of these chips.

[0083] Furthermore, the logic instructions in the aforementioned memory 330 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product, stored in a storage medium, includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0084] The memory 330 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory may optionally include a memory remotely located relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0085] Example 4 Based on the same concept, an embodiment of the present invention further provides a computer-readable storage medium storing a computer program. The computer program includes at least one code segment that can be executed by a main control device to control the main control device to implement the steps of the battery internal uniformity analysis method described in the above embodiments. For example, the steps include: S100, constructing a three-dimensional multi-physics field coupling model of the target battery, the three-dimensional multi-physics field coupling model including a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model; S200, setting a plurality of tab design schemes, wherein the tab parameters of each tab design scheme are different, and the tab parameters include at least the number of tabs, the tab width, and the tab position; S300. Perform simulation analysis based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results. The simulation analysis at least includes discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, current collector ohmic loss analysis, active material overpotential analysis, and battery temperature distribution analysis.

[0086] Based on the same technical concept, an embodiment of the present invention further provides a computer program, which, when executed by a main control device, is used to implement the above method embodiment.

[0087] The computer program may be stored in whole or in part on a computer-readable storage medium packaged with the processor, or may be stored in whole or in part on a memory not packaged with the processor.

[0088] Based on the same technical concept, an embodiment of the present invention further provides a processor for implementing the above method embodiment. The above processor may be a chip.

[0089] In summary, the battery internal uniformity analysis method, system, electronic device and storage medium provided by the present invention, through high-precision three-dimensional modeling and dynamic visualization technology, based on full-parameter uniformity simulation analysis, quantifies the spatial distribution of key parameters such as current density, temperature, polarization and overpotential inside the battery, fills the gap in experimental data, and provides data support for uniformity optimization. The multi-physics field dynamic coupling model integrates electrochemical-thermal-current fields, accurately simulates the interactive effects of tab parameter changes on multi-physics fields, improves simulation accuracy, and reveals the key role of tab parameters on uniformity. At the same time, by replacing experimental trial and error with simulation, the development cycle is greatly shortened, and the cost of single design verification is significantly reduced, achieving a dual innovation in design efficiency and cost-effectiveness, providing an efficient and economical solution for the development of high-performance batteries.

[0090] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0091] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for analyzing internal uniformity of a battery, characterized in that: The method comprises: Constructing a three-dimensional multi-physics field coupling model of the target battery, wherein the three-dimensional multi-physics field coupling model includes a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model; Setting a plurality of tab design schemes, wherein the tab parameters of each tab design scheme are different, and the tab parameters include at least the number of tabs, the width of the tabs and the position of the tabs; A simulation analysis is performed based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results, wherein the simulation analysis includes at least discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, current collector ohmic loss analysis, active material overpotential analysis, and battery temperature distribution analysis.

2. The battery internal uniformity analysis method according to claim 1, characterized in that: The three-dimensional multi-physics field coupling model of the target battery is constructed, including: Constructing a three-dimensional geometric body according to the positive electrode, negative electrode, separator, and tab of the target battery, and physically defining corresponding geometric regions of the three-dimensional geometric body according to material properties to obtain the three-dimensional geometric sub-model; Defining the electrochemical reaction equation, charge transfer equation, charge diffusion equation, material conservation equation, and boundary conditions of the target battery to obtain the electrochemical reaction sub-model; Constructing the thermal field sub-model according to the Joule heat, reaction heat and natural convection heat dissipation of the target battery; The three-dimensional geometric sub-model, the electrochemical reaction sub-model and the thermal field sub-model are coupled to obtain the three-dimensional multi-physics field coupling model.

3. The battery internal uniformity analysis method according to claim 1, characterized in that: The simulation analysis is a discharge curve analysis, and the simulation analysis is performed based on the three-dimensional multi-physics field coupling model and the tab design scheme, including: Under each of the tab designs, constant current discharge simulations at different rates were performed according to the three-dimensional multi-physics field coupling model, and a transient solver was used to obtain a voltage-time curve.

4. The battery internal uniformity analysis method according to claim 1, characterized in that: The simulation analysis is a DC internal resistance test analysis, and the simulation analysis is performed based on the three-dimensional multi-physics field coupling model and the tab design scheme, including: Under each of the tab designs, constant current discharge is performed for a preset time at a preset battery state of charge according to the three-dimensional multi-physics field coupling model, and the DC resistance is calculated based on the transient voltage response.

5. The battery internal uniformity analysis method according to claim 1, characterized in that: The simulation analysis is a current distribution and current density analysis, and the simulation analysis is performed based on the three-dimensional multi-physics field coupling model and the tab design scheme, including: Under each of the tab design schemes, the current transmission path is simulated according to the three-dimensional multi-physics field coupling model, and a current distribution line diagram and a current density distribution cloud diagram are generated according to the current transmission path.

6. The battery internal uniformity analysis method according to claim 1, characterized in that: The simulation analysis is an analysis of the ohmic loss of the current collector, and the simulation analysis is performed based on the three-dimensional multi-physics field coupling model and the tab design scheme, including: Under each of the tab design schemes, potential distribution data of the positive and negative electrodes of the target battery are extracted according to the three-dimensional multi-physics field coupling model, and the maximum potential difference is calculated according to the potential distribution data.

7. The battery internal uniformity analysis method according to claim 1, characterized in that: The simulation analysis is an active material overpotential analysis, and the simulation analysis is performed based on the three-dimensional multi-physics field coupling model and the tab design scheme, including: Under each of the tab designs, the overpotentials of lithium ion insertion and extraction reactions are calculated at the positive and negative active materials of the target battery according to the three-dimensional multi-physics field coupling model to obtain positive and negative electrode overpotential distribution cloud maps.

8. A battery internal uniformity analysis system, characterized in that: The system comprises: A model building module, used to build a three-dimensional multi-physics field coupling model of the target battery, wherein the three-dimensional multi-physics field coupling model couples a three-dimensional geometric sub-model, an electrochemical reaction sub-model, and a thermal field sub-model; A tab design module, configured to set a plurality of tab design schemes, wherein the tab parameters of each tab design scheme are different, and the tab parameters include at least the number of tabs, the width of the tabs, and the position of the tabs; A simulation analysis module is used to perform simulation analysis based on the three-dimensional multi-physics field coupling model and the tab design scheme to obtain uniformity analysis results. The simulation analysis includes at least discharge curve analysis, DC internal resistance test analysis, current distribution and current density analysis, collector ohmic loss analysis, active material overpotential analysis and battery temperature distribution analysis.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: The processor executes the computer program to implement the battery internal uniformity analysis method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the battery internal uniformity analysis method according to any one of claims 1 to 7 is implemented.

Images