Alkali metal ion secondary battery electrode coating simulation method, device and medium

Abstract

The invention relates to the technical field of coating, particularly provides an alkali metal ion secondary battery electrode coating simulation method, equipment and a medium, and aims to solve the technical problem of relatively high preparation cost of an existing lithium ion battery. In order to achieve the purpose, the electrode coating simulation method for the alkali metal ion secondary battery comprises the following steps: establishing a heterogeneous model of the alkali metal ion secondary battery; establishing a physical field control equation for describing the internal physical process of the alkali metal ion secondary battery; acquiring physical field characteristic parameters by using the heterogeneous model of the alkali metal ion secondary battery; solving a physical field control equation based on the physical field characteristic parameters; and obtaining an influence rule of different electrode coating modes on the battery performance according to a solving result. Therefore, high-precision simulation of the electrode coating process of the alkali metal ion secondary battery can be realized, and by simulating the influence of different electrode coating schemes on the battery performance, the design of the alkali metal ion secondary battery can be optimized, the overall performance of the battery can be improved, and the cost can be saved.

Description

Technical Field

[0001] The invention relates to the field of coating technology, and specifically provides an alkali metal ion secondary battery electrode coating simulation method, equipment and medium. Background Art

[0002] Due to the excessive use of non-renewable energy such as oil and coal, the earth's environment has been severely damaged. As the core technology for the transformation of non-renewable energy to green and low-carbon energy, electrochemical energy storage technology plays an important role in solving energy crises. As an important part of the development of electrochemical energy storage technology, lithium-ion batteries have improved their safety performance, long-term performance, high specific energy performance and environmental protection performance, which all determine the widespread application of electrochemical energy storage technology in the future.

[0003] Most of the existing lithium-ion batteries are prepared through production lines. Lithium batteries prepared in this way require a large number of electrochemical performance tests, and the final solution requires multiple repeated experiments, which consumes a lot of manpower, material costs and testing resources and cannot meet actual needs. Summary of the invention

[0004] In order to overcome the above defects, the present application is proposed to provide a solution or at least partially solve the technical problem of high preparation cost of existing lithium batteries. The present application provides an alkali metal ion secondary battery electrode coating simulation method, device and medium.

[0005] In a first aspect, the present application provides an alkali metal ion secondary battery electrode coating simulation method, the method comprising:

[0006] Establish a heterogeneous model for alkali metal ion secondary batteries;

[0007] Establishing a physical field control equation describing the internal physical process of the alkali metal ion secondary battery;

[0008] Acquiring physical field characteristic parameters using the heterogeneous model of the alkali metal ion secondary battery;

[0009] Solving the physical field control equation based on the physical field characteristic parameters;

[0010] Based on the solution results, the influence of different electrode coating methods on battery performance is obtained.

[0011] In one embodiment of the present application, the establishing of the heterogeneous model of the alkali metal ion secondary battery comprises:

[0012] Obtaining physical parameters of alkali metal ion secondary batteries;

[0013] Constructing the heterogeneous model of the alkali metal ion secondary battery based on the physical parameters;

[0014] The property information of the heterogeneous model of the alkali metal ion secondary battery is set.

[0015] In one embodiment of the present application, the physical parameters include geometric parameters, alkali metal ion liquid phase diffusion parameters and alkali metal ion solid phase diffusion parameters of the alkali metal ion secondary battery, and the geometric parameters include at least the particle size range of the positive electrode and the negative electrode of the alkali metal ion secondary battery;

[0016] The heterogeneous model of the alkali metal ion secondary battery comprises a positive electrode, a negative electrode and a separator located between the positive electrode and the negative electrode, wherein the positive electrode comprises an upper positive electrode layer and a lower positive electrode layer.

[0017] In one embodiment of the present application, the setting of the property information of the heterogeneous model of the alkali metal ion secondary battery includes: setting the material, boundary and initial value of the heterogeneous model of the alkali metal ion secondary battery.

[0018] In one embodiment of the present application, the material for setting the heterogeneous model of the alkali metal ion secondary battery includes: using lithium iron phosphate as the material of the upper positive electrode layer and the lower positive electrode layer, and using graphite as the material of the negative electrode;

[0019] The setting of the boundary of the heterogeneous model of the alkali metal ion secondary battery includes: setting the upper positive electrode layer as an electrode current boundary, and setting the negative electrode as a grounding boundary;

[0020] The setting of the initial values ​​includes: setting the initial concentration of the electrolyte, the initial potential of the electrolyte, the initial boundary voltage and the initial capacity of the alkali metal ion secondary battery.

[0021] In one embodiment of the present application, before solving the physical field control equation based on the physical field characteristic parameters, the method further includes: meshing the heterogeneous model of the alkali metal ion secondary battery.

[0022] In one embodiment of the present application, the influence of different electrode coating methods on battery performance is obtained according to the solution results, including:

[0023] Get the solution results corresponding to each grid;

[0024] Determining an evaluation index of the alkali metal ion secondary battery according to each solution result;

[0025] Based on the evaluation index, the influence of different electrode coating methods with different particle size distributions on the performance of alkali metal ion secondary batteries is obtained.

[0026] In one embodiment of the present application, before obtaining the influence of different electrode coating methods on battery performance according to the solution results, the method further includes:

[0027] Define the dilute species transport field;

[0028] Establishing a coupling relationship between the dilute species transfer field and the electrochemical field;

[0029] Acquiring the alkali metal ion flux on the electrode reaction surface based on the coupling relationship;

[0030] obtaining a solid phase alkali metal concentration based on the alkali metal ion flux;

[0031] The obtaining of the influence of different electrode coating methods on battery performance according to the solution results includes: obtaining the influence of different electrode coating methods on battery performance based on the solution results and the solid phase alkali metal concentration.

[0032] In a second aspect, an electronic device is provided, comprising:

[0033] at least one processor;

[0034] and, a memory communicatively coupled to the at least one processor;

[0035] Wherein, a computer program is stored in the memory, and when the computer program is executed by the at least one processor, the aforementioned alkali metal ion secondary battery electrode coating simulation method.

[0036] In a third aspect, a computer-readable storage medium is provided, wherein a plurality of program codes are stored therein, wherein the program codes are suitable for being loaded and run by a processor to execute any of the aforementioned alkali metal ion secondary battery electrode coating simulation methods.

[0037] The above one or more technical solutions of this application have at least one or more of the following Beneficial effects:

[0038] The alkali metal ion secondary battery electrode coating simulation method in this application includes: establishing a heterogeneous model of an alkali metal ion secondary battery; establishing a physical field control equation that describes the internal physical process of an alkali metal ion secondary battery; obtaining physical field characteristic parameters using the heterogeneous model of an alkali metal ion secondary battery; solving the physical field control equation based on the physical field characteristic parameters; and obtaining the influence of different electrode coating methods on battery performance according to the solution results. In this way, a high-precision simulation of the electrode coating process of an alkali metal ion secondary battery can be achieved. By simulating the influence of different electrode coating schemes on battery performance, the design of alkali metal ion secondary batteries can be optimized, the overall performance of the battery can be improved, and costs can be saved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] 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:

[0040] Figure 1 This is a schematic diagram of the main process of a simulation method for coating an alkali metal ion secondary battery electrode in one embodiment of the present application;

[0041] Figure 2 is a schematic diagram of a heterogeneous model of an alkali metal ion secondary battery in one embodiment of the present application;

[0042] Figure 3 , Figure 4 and Figure 5 It is a schematic diagram of solid phase lithium concentration distribution of a lithium ion battery heterogeneous model with different particle size ranges under charging conditions in an embodiment of the present application;

[0043] Figure 6 is a voltage curve of a lithium-ion battery heterogeneous model with different particle size ranges at a 1C charging rate in one embodiment of the present application;

[0044] Figure 7 It is a schematic diagram of the main structure of an alkali metal ion secondary battery electrode coating simulation device in one embodiment of the present application;

[0045] Figure 8 It is a schematic diagram of the structure of an electronic device in one embodiment of the present application. DETAILED DESCRIPTION

[0046] 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.

[0047] 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, memory, and may also include software parts, such as program code, 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. Non-temporary computer-readable storage media include any suitable medium that can store program code, such as a disk, a hard disk, an optical disk, a flash memory, a read-only memory, a random access memory, etc. The term "A and / or B" means all possible combinations of A and B, such as only A, only 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 only A, only B or A and B. The singular terms "one" and "the" may also include plural forms.

[0048] Currently, most traditional lithium-ion batteries are prepared through production lines. Lithium batteries prepared in this way undergo a large number of electrochemical performance tests. The final solution requires multiple repeated experiments, which consumes a lot of manpower, material costs and testing resources and cannot meet actual needs.

[0049] To this end, the present application proposes an alkali metal ion secondary battery electrode coating simulation method, equipment and medium.

[0050] Alkali metal ion secondary batteries refer to rechargeable batteries that use alkali metal ions (such as lithium, sodium, potassium, etc.) as charge carriers. Alkali metal secondary batteries can be lithium ion batteries, sodium ion batteries, or potassium ion batteries.

[0051] It should be understood that in order to make the purpose, technical solution and advantages of the present invention clearer, the following is a detailed description of the alkali metal ion secondary battery electrode coating simulation method of the present application in combination with the accompanying drawings and embodiments, taking a lithium ion battery as an example of an alkali metal ion secondary battery. It should be understood by those skilled in the art that the specific embodiments described herein are only used to explain the present invention, and are not intended to limit the alkali metal ion secondary battery electrode coating simulation method described in the present invention to use a lithium ion battery as an alkali metal ion secondary battery.

[0052] See attached Figure 1 , Figure 1 It is a schematic diagram of the main process of a simulation method for coating an alkali metal ion secondary battery electrode according to an embodiment of the present application.

[0053] like Figure 1As shown, the alkali metal ion secondary battery electrode coating simulation method in the embodiment of the present application mainly includes the following steps S10 to S50.

[0054] Step S10: establishing a heterogeneous model of an alkali metal ion secondary battery.

[0055] The heterogeneous model of alkali metal ion secondary batteries is a mathematical model used to simulate the internal heterogeneous structure of alkali metal ion secondary batteries. The heterogeneous model of alkali metal ion secondary batteries takes into account the heterogeneity of the material properties inside the battery, especially the different layers (upper and lower layers) in the positive electrode sheet have different particle size distributions. This model can more accurately reflect the physical properties of the actual battery.

[0056] Step S20: establishing a physical field control equation describing the internal physical process of the alkali metal ion secondary battery.

[0057] The physical field control equations are a set of differential equations that describe the internal physical processes of alkali metal ion secondary batteries, usually including processes such as mass transfer and diffusion of alkali metal ions in the electrolyte, diffusion in the active material, conduction of electrons, and electrochemical interface reactions.

[0058] Step S30: obtaining physical field characteristic parameters using the alkali metal ion secondary battery heterogeneous model.

[0059] Physical field characteristic parameters refer to specific physical quantities used as known quantities in physical field control equations. Physical field characteristic parameters describe key states in electrochemical systems and can be obtained through alkali metal ion secondary battery coating simulation experiment measurements.

[0060] Step S40: Solving the physical field control equation based on the physical field characteristic parameters.

[0061] Step S50: Obtain the influence of different electrode coating methods on battery performance according to the solution results.

[0062] The influence of electrode coating method on battery performance refers to the influence of changing the characteristics of electrode coating (such as particle size distribution, coating thickness, etc.) on battery performance (such as capacity, internal resistance, cycle life, etc.).

[0063] Based on the above steps S10 to S50, first establish a heterogeneous model of an alkali metal ion secondary battery; establish a physical field control equation that describes the internal physical process of the alkali metal ion secondary battery; use the heterogeneous model of the alkali metal ion secondary battery to obtain physical field characteristic parameters; solve the physical field control equation based on the physical field characteristic parameters; and obtain the influence of different electrode coating methods on battery performance based on the solution results. In this way, a high-precision simulation of the electrode coating process of an alkali metal ion secondary battery can be achieved. By simulating the influence of different electrode coating schemes on battery performance, the design of the alkali metal ion secondary battery can be optimized, the overall performance of the battery can be improved, and the cost can be saved.

[0064] The above steps S10 to S50 are further explained below.

[0065] Specifically, step S10 can be implemented through the following steps S101 to S103.

[0066] Step S101: obtaining physical parameters of the alkali metal ion secondary battery.

[0067] In a specific embodiment of the present application, the physical parameters include geometric parameters, alkali metal ion liquid phase diffusion parameters and alkali metal ion solid phase diffusion parameters of the alkali metal ion secondary battery, and the geometric parameters include at least the particle size range of the positive and negative electrodes of the alkali metal ion secondary battery.

[0068] Specifically, based on the parameters of the actual battery cells, the parameters required for the heterogeneous model of the alkali metal ion secondary battery are obtained, including geometric parameters such as the thickness of the upper positive electrode, the thickness of the lower positive electrode, the thickness of the negative electrode, the thickness of the separator, the particle size range of the positive and negative electrodes, etc., the liquid phase diffusion coefficient, tortuosity and liquid phase volume fraction that describe the liquid phase diffusion of alkali metal ions, the solid phase diffusion coefficient, active specific surface area and solid phase volume fraction that describe the solid phase diffusion of alkali metal ions, etc., and no specific restrictions are made on this.

[0069] Step S102: constructing a heterogeneous model of an alkali metal ion secondary battery based on physical parameters.

[0070] In a specific embodiment of the present application, the heterogeneous model of the alkali metal ion secondary battery includes a positive electrode, a negative electrode and a separator located between the positive electrode and the negative electrode, and the positive electrode includes an upper positive electrode layer and a lower positive electrode layer.

[0071] Specifically, the heterogeneous model of alkali metal ion secondary battery adopts a single-layer electrode sheet two-dimensional structure model, which divides the positive electrode into an upper positive electrode layer and a lower positive electrode layer to achieve double-layer coating of the positive electrode sheet. A Java language script can be written to generate the geometric shape of the heterogeneous model of alkali metal ion secondary battery using physical parameters. The geometric structure includes an upper positive electrode layer, a positive electrode conductive binder, a lower positive electrode layer, a separator, a negative electrode conductive binder, and a negative electrode. For example, Figure 2 It can be used as an example of the heterogeneous model of the alkali metal ion secondary battery.

[0072] Step S103: setting the property information of the heterogeneous model of the alkali metal ion secondary battery.

[0073] In a specific embodiment of the present application, the setting of the property information of the heterogeneous model of the alkali metal ion secondary battery includes: setting the material, boundary and initial value of the heterogeneous model of the alkali metal ion secondary battery.

[0074] In a specific embodiment of the present application, the material setting of the alkali metal ion secondary battery heterogeneous model includes: using lithium iron phosphate as the material of the upper positive electrode layer and the lower positive electrode layer, and using graphite as the negative electrode material; the boundary setting of the alkali metal ion secondary battery heterogeneous model includes: setting the upper positive electrode layer as the electrode current boundary, and setting the negative electrode as the grounding boundary; the setting of initial values ​​includes: setting the initial concentration of the electrolyte, the initial potential of the electrolyte, the initial boundary voltage and the initial capacity of the alkali metal ion secondary battery.

[0075] Specifically, different domains in the heterogeneous model of alkali metal ion secondary batteries need to be represented by different materials. For example, the upper positive electrode material particle domain and the lower positive electrode material particle domain are represented by lithium iron phosphate material, and the negative electrode material particle domain is represented by graphite. The particle size range has been defined in the generated model geometry. In addition to the round active particles, the positive and negative electrodes also include conductive binders, and the porosity of the diaphragm domain can be further defined.

[0076] Furthermore, an electrode current boundary condition IPP_1C is assigned to the top of the upper positive electrode layer, which means that at the top of the upper positive electrode layer, the current flows in or out at a rate of 1 times the rated capacity of the battery. 1C refers to the rated capacity (Capacity) of the battery, and the unit is usually ampere-hour (Ah) or milliampere-hour (mAh). A ground boundary condition is assigned to the negative electrode, which means that the potential of the negative electrode is fixed to zero as a reference potential.

[0077] Further, initial conditions are set for the heterogeneous model of the alkali metal ion secondary battery to reflect the state of the alkali metal ion secondary battery at the beginning of the simulation. Specifically, the initial concentration of alkali metal ions in the electrolyte (initial electrolyte concentration), the initial potential of the electrolyte, the initial voltage difference across the battery (initial boundary voltage), and the initial capacity of the battery can be set, wherein the initial capacity of the battery can be the maximum storage capacity of the battery.

[0078] By setting the positive and negative electrode materials, boundary conditions, and initial values ​​in the heterogeneous battery model of alkali metal ion secondary batteries, the behavior of alkali metal ion secondary batteries under different operating conditions can be simulated, which is conducive to accurately analyzing the impact of different layer particle size distributions in the positive electrode double-layer coating model on the performance of alkali metal ion secondary batteries.

[0079] The above is a further description of step S10 , and the following is a further description of step S20 .

[0080] The Newman model describes the combination of porous electrode theory and concentrated solution theory to simulate the electrochemical reaction of the battery, which mainly includes the mass transfer and diffusion of alkali metal ions in the electrolyte, the diffusion in the active material, the conduction of electrons in the active material, and the electrochemical interface reaction. Therefore, the physical field control equations include the solid phase charge conservation equation, the liquid phase charge conservation equation, the solid phase material conservation equation, the liquid phase material conservation equation, and the BV equation.

[0081] Specifically, during the electrochemical reaction, the solid phase charge conservation is expressed by the solid phase Ohm's law, the liquid phase charge conservation is expressed by the liquid phase Ohm's law, the solid phase substance conservation is expressed by Fick's second law, the liquid phase substance conservation is expressed by the Nernst-Planck equation, and the interfacial reaction is expressed by the classic BV equation.

[0082] Ohm's law in the solid phase is expressed as:

[0083] where σ eff is the effective solid conductivity (S / m), is the solid phase potential (V), j is the local current density (A / m 3 ).

[0084] Ohm's law in liquid phase is expressed as:

[0085] Among them, κ eff is the effective conductivity of the liquid phase (S / m), is the liquid phase potential (V), Effective diffusion ion conductivity (S / m), j is the volume current density (A / m 3 ), C e is the concentration of alkali metal ions in the liquid phase (mol / m 3 ).

[0086] Fick's second law is expressed as:

[0087] Among them, D S is the solid phase diffusion coefficient (m 2 / s), r is the radius of the active material particle (m), c s is the solid phase alkali metal concentration (mol / m 3 ), x is the distance and t is the time.

[0088] The Nernst-Planck equation is expressed as:

[0089] Among them, ε e is the volume fraction of the electrolyte, is the effective diffusion coefficient, is the rate of change of ion concentration over time, is the effective diffusion coefficient of the electrolyte, is the spatial gradient of ion concentration in the electrolyte, F is the Faraday constant, is the migration number of positive ions, and J is the current density.

[0090] The interfacial reaction is described using the classic BV equation:

[0091] Where i is the local current density (A / m 2 ), i0 is the exchange current density (A / m 2 ), α a , α c are the transfer coefficients of the negative and positive electrodes respectively, F is the Faraday constant, and η is the overpotential (V).

[0092] The above is a further description of step S20 , and the following is a further description of step S30 .

[0093] For step S30, the heterogeneous model of the alkali metal ion secondary battery constructed in the above steps can be used to perform simulation tests on the alkali metal ion secondary battery, such as charging tests or discharging tests, to obtain the physical field characteristic parameters of the alkali metal ion secondary battery. The physical field characteristic parameters can be known quantities in the above physical field control equations. For example, σ in the expression of the solid phase Ohm's law eff , κ in the expression of Ohm's law in liquid phase eff , D in the expression of Fick's second law S and r, ε in the Nernst-Planck equation e , F, i0, α in the BV equation a , α c , F can both be physical field characteristic parameters.

[0094] The above is a further description of step S30 , and the following is a further description of step S40 .

[0095] In a specific embodiment of the present application, before solving the physical field control equation based on the physical field characteristic parameters, the method further includes: meshing the heterogeneous model of the alkali metal ion secondary battery.

[0096] Specifically, different types of grids can be used to divide different regions of the heterogeneous model of the alkali metal ion secondary battery. For example, the positive electrode and the negative electrode can be divided by free triangle grids, and the separator between the positive electrode and the negative electrode can be divided by regular quadrilateral grids.

[0097] After meshing the heterogeneous model of the alkali metal ion secondary battery, multiple grids can be obtained. Then, the finite element method or finite volume method can be used to solve the physical field control equation on each grid to obtain the solution corresponding to each grid (i.e., the unknown quantity in the above physical field control equation).

[0098] The above is a further description of step S40 , and the following is a further description of step S50 .

[0099] Specifically, step S50 can be implemented through the following steps S501 to S503.

[0100] Step S501: Obtain the solution result corresponding to each grid.

[0101] The solution results corresponding to each grid obtained should cover the entire battery structure, including different areas such as the positive electrode, negative electrode, and separator. The solution results corresponding to each grid are unknown quantities in the above-mentioned physical field control equations, such as the relationship between the overpotential and time.

[0102] Step S502: determining evaluation indicators of the alkali metal ion secondary battery according to the solution results.

[0103] Specifically, through the solution results corresponding to each grid, the average value of the solution results of all grids can be used as the evaluation index of the alkali metal ion secondary battery.

[0104] Step S503: Obtaining the influence of different electrode coating methods with different particle size distributions on the performance of the alkali metal ion secondary battery based on the evaluation index.

[0105] Specifically, the changing trends of these macroscopic evaluation indicators can be further analyzed to evaluate the impact of different particle size distributions on battery performance.

[0106] By studying the changes in evaluation indicators under different particle size distribution conditions, we can reveal the influence of different particle size distributions on battery performance, which is beneficial to improving battery design and optimization effects. It can help researchers better understand the physical processes inside the battery and guide the selection and design of battery materials to improve the energy density, cycle life and safety of the battery.

[0107] In a specific embodiment of the present application, before establishing the physical field control equations that describe the internal physical processes of the alkali metal ion secondary battery, the method also includes: defining a dilute species transfer field; establishing a coupling relationship between the dilute species transfer field and the electrochemical field; obtaining the alkali metal ion flux on the electrode reaction surface based on the coupling relationship; obtaining the solid phase alkali metal concentration based on the alkali metal ion flux; the method of obtaining the influence of different electrode coating methods on battery performance based on the solution results includes: obtaining the influence of different electrode coating methods on battery performance based on the solution results and the solid phase alkali metal concentration.

[0108] Dilute Species Transport Field is used to describe the transport behavior of alkali metal ions in electrolytes.

[0109] Since the solid-phase alkali metal concentration in the physical field control equation is specifically expressed as the rate of change of the solid-phase alkali metal concentration over time, it will not be presented in the final solution. In order to more directly obtain the change of the solid-phase alkali metal concentration, the dilute species transfer field can be added to the heterogeneous model of the alkali metal ion secondary battery. The coupling between the electrochemical field and the dilute species transfer field is set by the electrode reaction surface, and then the alkali metal ion flux on the electrode reaction surface is calculated, and the solid-phase alkali metal concentration is further obtained by the alkali metal ion flux. The calculation formula of the alkali metal ion flux can be expressed as: J=i / F

[0110] Where F is the Faraday constant (C / mol), i is the local current density (A / m 2 ), J is the alkali metal ion flux (mol / s / m 2 ).

[0111] The calculation formula of solid phase alkali metal concentration can be expressed as:

[0112] Among them, c s is the solid phase alkali metal concentration, and J is the alkali metal ion flux.

[0113] The solid-phase alkali metal concentration plays an important role in predicting and optimizing battery performance. The concentration of alkali metal ions reflects the number and activity of alkali metal ions inside the battery, which has an important impact on the overall performance of the battery. The higher the concentration of alkali metal ions, the more alkali metal ions can be embedded or de-embedded, which may lead to higher energy storage capacity. In other words, the higher the concentration of alkali metal ions, the higher the electrochemical activity may be, which means that the battery may have a higher energy density.

[0114] Combining the solution results of the physical field control equations with the solid phase alkali metal concentration to analyze the impact of different electrode coating methods on battery performance can provide a deeper understanding of the internal working principles of the battery, optimize battery design, and ultimately achieve higher performance, lower cost, safer and more reliable battery products.

[0115] For example, the alkali metal ion secondary battery coating simulation method described in the above embodiment can be used to construct a heterogeneous model of a lithium battery with a double-layer positive electrode coating, and study the effect of particle size distribution of different layers on electrochemical performance, such as Figure 3 , Figure 4 and Figure 5 As shown in the figure, three different heterogeneous models of lithium-ion batteries with double-layer positive electrode coating were constructed. Figure 3 It is a lithium-ion battery heterogeneous model with double-layer coating, with the upper layer particles ranging from 3-6um and the lower layer particles ranging from 3-6um, referred to as large pole particles; Figure 4 It is a lithium-ion battery heterogeneous model with double-layer coating, with the upper layer particles ranging from 3-6um and the lower layer particles ranging from 2-4um, referred to as the upper layer large particles / lower layer small particles of the electrode; Figure 5 The double-layer coated lithium-ion battery heterogeneous model has an upper layer particle range of 2-4um and a lower layer particle range of 2-4um, which is called small pole piece particles.

[0116] Figure 6 for Figure 3 , Figure 4 and Figure 5 The voltage curves of the heterogeneous lithium-ion battery model corresponding to the three different structures at a charging rate of 1C are shown. Figure 6 It can be seen that at the same charging rate, the longer the charging time, the larger the corresponding capacity, that is, the capacity of the upper large particles / lower small particles > the capacity of the electrode small particles > the capacity of the electrode large particles.

[0117] from Figure 3 , Figure 4 and Figure 5From the solid phase lithium concentration distribution diagram in , we can see that the degree of lithium removal of the positive electrode particles is related to the particle radius. The smaller the radius, the smaller the solid phase lithium concentration, that is, more lithium is removed; the larger the radius, the greater the solid phase lithium concentration, that is, less lithium is removed. In addition, the degree of lithium removal is also related to the location of the particles. The closer to the diaphragm, the greater the degree of lithium removal. Among them, the difference in electrochemical performance caused by the unevenness of the pole piece cannot be simulated by the homogeneous model.

[0118] from Figure 3 , Figure 4 and Figure 5 It can also be seen that when the electrode structure is upper large particles / lower small particles, the maximum solid phase lithium concentration is 3.66×10 3 mol / m 3 , which is the smallest among the three structures, indicating that the positive electrode releases the most lithium when charging; when the electrode structure is large particles, the maximum solid phase lithium concentration is 4.12×10 3 mol / m 3 The reason is that the particles are too large, resulting in excessive solid phase diffusion polarization and less lithium extraction, so there is still a large solid phase lithium concentration gradient inside the particles; when the entire electrode is small particles, the maximum solid phase lithium concentration is 3.84×10 3 mol / m 3 The reason is that the electrode particles are too small, which increases the tortuosity and the polarization of lithium ion liquid phase diffusion. Therefore, the optimal design of the battery cell electrode can be achieved by fully considering the reasonable design of the pore size and particle gradient.

[0119] It should be pointed out that although the various steps in the above embodiments are described in a specific order, those skilled in the art can understand that in order to achieve the effect of the present application, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in other orders. These changes are within the scope of protection of the present application.

[0120] Furthermore, the present application also provides an alkali metal ion secondary battery electrode coating simulation device.

[0121] See attached Figure 7 , Figure 7 It is a main structural block diagram of an alkali metal ion secondary battery electrode coating simulation device according to an embodiment of the present application.

[0122] like Figure 7As shown, the alkali metal ion secondary battery electrode coating simulation device in the embodiment of the present application mainly includes a first establishment module 11, a second establishment module 12, a first acquisition module 13, a solution module 14 and a second acquisition module 15. In some embodiments, one or more of the first establishment module 11, the second establishment module 12, the first acquisition module 13, the solution module 14 and the second acquisition module 15 can be combined into one module.

[0123] In some embodiments, the first establishing module 11 may be configured to establish an alkali metal ion secondary battery heterogeneous model.

[0124] The second establishing module 12 may be configured to establish a physical field control equation describing an internal physical process of the alkali metal ion secondary battery.

[0125] The first acquisition module 13 may be configured to acquire physical field characteristic parameters using an alkali metal ion secondary battery heterogeneous model.

[0126] The solving module 14 may be configured to solve the physical field control equations based on the physical field characteristic parameters.

[0127] The second acquisition module 15 may be configured to acquire the influence of different electrode coating methods on the battery performance according to each solution result.

[0128] In one implementation, the description of the specific implementation functions can refer to steps S10-S50.

[0129] The alkali metal ion secondary battery electrode coating simulation device is used to perform Figure 1 The alkali metal ion secondary battery electrode coating simulation method embodiment shown in the figure has similar technical principles, technical problems solved and technical effects produced. Technicians in this technical field can clearly understand that for the convenience and conciseness of description, the specific working process and related instructions of the alkali metal ion secondary battery electrode coating simulation device can refer to the contents described in the embodiment of the alkali metal ion secondary battery electrode coating simulation method, which will not be repeated here.

[0130] Further, it should be understood that since the setting of each module is only for illustrating the functional units of the device of the present application, the physical devices corresponding to these modules may be the processor itself, or a part of the software in the processor, a part of the hardware, or a part of the combination of software and hardware. Therefore, the number of each module in the figure is only schematic.

[0131] It is understood by those skilled in the art that each module in the device can be adaptively split or merged. Such splitting or merging of specific modules will not cause the technical solution to deviate from the principle of the present application, and therefore, the technical solutions after splitting or merging will fall within the protection scope of the present application.

[0132] It is understood by those skilled in the art that all or part of the processes in the method for implementing the above-mentioned embodiment of the present application can also be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory, random access memory, electrical carrier signal, telecommunication signal and software distribution medium, etc. that can carry the computer program code.

[0133] Furthermore, the present application also provides an electronic device, which may include at least one processor; and a memory connected to the at least one processor; wherein the memory stores a computer program, and when the computer program is executed by the at least one processor, the alkali metal ion secondary battery electrode coating simulation method described in any of the above embodiments is implemented. Figure 8 As shown, Figure 8 exemplarily shows the structure of an electronic device, which includes a processor 100 and a memory 200.

[0134] Further, the present application also provides a computer-readable storage medium. In a computer-readable storage medium embodiment according to the present application, the computer-readable storage medium may be configured to store a program for executing the alkali metal ion secondary battery electrode coating simulation method of the above-mentioned method embodiment, and the program may be loaded and run by the processor to implement the above-mentioned alkali metal ion secondary battery electrode coating simulation method. 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 section of the embodiments of the present application. The computer-readable storage medium may be a memory 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.

[0135] So far, the technical solutions of the present application have been described in conjunction with the specific implementations shown in the accompanying drawings, but 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 implementations. 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 simulation method for coating an alkali metal ion secondary battery electrode, characterized in that: The method comprises: Establish a heterogeneous model for alkali metal ion secondary batteries; Establishing a physical field control equation describing the internal physical process of the alkali metal ion secondary battery; Acquiring physical field characteristic parameters using the heterogeneous model of the alkali metal ion secondary battery; Solving the physical field control equation based on the physical field characteristic parameters; Based on the solution results, the influence of different electrode coating methods on battery performance is obtained.

2. The alkali metal ion secondary battery electrode coating simulation method according to claim 1, characterized in that: The establishing of the heterogeneous model of the alkali metal ion secondary battery comprises: Obtaining physical parameters of alkali metal ion secondary batteries; Constructing the heterogeneous model of the alkali metal ion secondary battery based on the physical parameters; The property information of the heterogeneous model of the alkali metal ion secondary battery is set.

3. The alkali metal ion secondary battery electrode coating simulation method according to claim 2, characterized in that: The physical parameters include geometric parameters, alkali metal ion liquid phase diffusion parameters and alkali metal ion solid phase diffusion parameters of the alkali metal ion secondary battery, and the geometric parameters include at least the particle size range of the positive electrode and the negative electrode of the alkali metal ion secondary battery; The heterogeneous model of the alkali metal ion secondary battery comprises a positive electrode, a negative electrode and a separator located between the positive electrode and the negative electrode, wherein the positive electrode comprises an upper positive electrode layer and a lower positive electrode layer.

4. The alkali metal ion secondary battery electrode coating simulation method according to claim 3, characterized in that: The setting of the property information of the heterogeneous model of the alkali metal ion secondary battery includes: setting the material, boundary and initial value of the heterogeneous model of the alkali metal ion secondary battery.

5. The alkali metal ion secondary battery electrode coating simulation method according to claim 4, characterized in that: The materials for setting the heterogeneous model of the alkali metal ion secondary battery include: using lithium iron phosphate as the material of the upper positive electrode layer and the lower positive electrode layer, and using graphite as the material of the negative electrode; The setting of the boundary of the heterogeneous model of the alkali metal ion secondary battery includes: setting the upper positive electrode layer as an electrode current boundary, and setting the negative electrode as a grounding boundary; The setting of the initial values ​​includes: setting the initial concentration of the electrolyte, the initial potential of the electrolyte, the initial boundary voltage and the initial capacity of the alkali metal ion secondary battery.

6. The alkali metal ion secondary battery electrode coating simulation method according to claim 1, characterized in that: Before solving the physical field control equation based on the physical field characteristic parameters, the method further includes: meshing the heterogeneous model of the alkali metal ion secondary battery.

7. The alkali metal ion secondary battery electrode coating simulation method according to claim 6, characterized in that: According to the solution results, the influence of different electrode coating methods on battery performance is obtained, including: Get the solution results corresponding to each grid; Determining an evaluation index of the alkali metal ion secondary battery according to each solution result; Based on the evaluation index, the influence of different electrode coating methods with different particle size distributions on the performance of alkali metal ion secondary batteries is obtained.

8. The alkali metal ion secondary battery electrode coating simulation method according to claim 1, characterized in that: Before obtaining the influence of different electrode coating methods on battery performance according to the solution results, the method further includes: Define the dilute species transport field; Establishing a coupling relationship between the dilute species transfer field and the electrochemical field; Acquiring the alkali metal ion flux on the electrode reaction surface based on the coupling relationship; obtaining a solid phase alkali metal concentration based on the alkali metal ion flux; The obtaining of the influence of different electrode coating methods on battery performance according to the solution results includes: obtaining the influence of different electrode coating methods on battery performance based on the solution results and the solid phase alkali metal concentration.

9. An electronic device, characterized in that: include: at least one processor; and, a memory communicatively coupled to the at least one processor; Wherein, a computer program is stored in the memory, and when the computer program is executed by the at least one processor, the alkali metal ion secondary battery electrode coating simulation method according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium storing a plurality of program codes, characterized in that: The program code is suitable for being loaded and run by a processor to execute the alkali metal ion secondary battery electrode coating simulation method according to any one of claims 1 to 8.

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