Component modified material screening method and device, storage medium, equipment, halide electrolyte material and secondary battery

Abstract

The invention provides a component modified material screening method and device, a storage medium, equipment, a halide electrolyte material and a secondary battery, and the method comprises the steps: obtaining a plurality of candidate component modified materials for metal halide electrolyte, predicting the phase structure of each candidate component modified material according to a cationic polarization factor, and obtaining a three-dimensional crystal structure of each candidate component modified material based on the phase structure, de-weighting each three-dimensional crystal structure, reducing the screening amount, and then calculating the lithium ion conductivity and water molecule adsorption energy of the simplified candidate component modified material at room temperature. And evaluating the electrochemical performance and improving the wet air stability of the metal halide electrolyte, so as to screen out an effective component modified material. Therefore, the screening efficiency of the component modified material for improving the wet air stability of the metal halide electrolyte is effectively improved, and the screening cost is reduced, so that the research and development requirements of rapid iteration of battery materials can be met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a component modified material screening method and device, a storage medium, an equipment, a halide electrolyte material and a secondary battery. BACKGROUND

[0002] The rapid development of new energy vehicle industry puts forward higher requirements for lithium ion batteries with high safety and high energy density. As a new type of electrolyte material replacing traditional liquid electrolyte, solid electrolyte has great advantages in high safety and vehicle energy density. Among them, metal halide solid electrolyte is concerned due to its high lithium ion conductivity and good mechanical properties. However, the problem of wet air stability of metal halide solid electrolyte is an important obstacle to its large-scale application. In order to improve the stability of metal halide solid electrolyte in wet air, it needs to be modified.

[0003] At present, for the screening of modified materials for improving the wet air stability of metal halide solid electrolyte, a specific modification scheme is usually selected by technical personnel according to experience, and then the corresponding electrolyte is synthesized and assembled into a battery for testing. In order to screen a modified material meeting the performance requirements, the above process needs to be repeated hundreds of times, which is complex and inefficient, and it is difficult to meet the rapid iteration of battery material research and development requirements. SUMMARY

[0004] The purpose of the present application is to provide a component modified material screening method, device, storage medium, equipment, halide electrolyte material and secondary battery, which aims to solve the problem of low screening efficiency of the related art of the modified material screening method for improving the wet air stability of metal halide solid electrolyte, and difficult to meet the rapid iteration of battery material research and development requirements.

[0005] In a first aspect, the present application provides a component modified material screening method, comprising: obtaining a plurality of candidate component modified materials for metal halide electrolyte; predicting the phase structure of each candidate component modified material according to the cation polarization factor of each candidate component modified material, obtaining the three-dimensional crystal structure of each candidate component modified material based on the phase structure, and performing deduplication on the three-dimensional crystal structure to obtain the simplified candidate component modified material; screening the simplified candidate component modified material according to the lithium ion conductivity of the simplified candidate component modified material at room temperature and the water molecule adsorption energy, and obtaining the target component modified material.

[0006] In the implementation process, a plurality of candidate component modification materials for the metal halide electrolyte are obtained, the phase structure of each candidate component modification material is predicted according to the cation polarization factor, the three-dimensional crystal structure of each candidate component modification material is obtained based on the phase structure, and the three-dimensional crystal structures are de-duplicated to reduce the screening amount. Then, the lithium ion conductivity of the candidate component modification material after simplification at room temperature and the water molecule adsorption energy are calculated, the electrochemical performance and the effect of improving the wet air stability of the metal halide electrolyte are evaluated, and then the effective component modification material is screened. In this way, the screening efficiency of the component modification material for improving the wet air stability of the metal halide electrolyte is effectively improved, and the screening cost is reduced, thereby meeting the rapid iteration of battery material research and development requirements.

[0007] Further, in some examples, the cation polarization factor of the candidate component modification material is calculated according to the ion potential molar ratio of lithium elements, metal elements and halogen elements in the candidate component modification material, and a target proportionality coefficient; the ion potential molar ratio is the sum of the proportion of the atomic number and the ion radius of the corresponding element; and the target proportionality coefficient is determined according to the valence and atomic number of the introduced heterogeneous metal element of the candidate component modification material.

[0008] In the implementation process, a specific way is provided to accurately calculate the cation polarization factor of each candidate component modification material, thereby laying a good foundation for subsequent prediction of the phase structure of each component modification material.

[0009] Further, in some examples, the phase structure of each candidate component modification material is predicted according to the cation polarization factor of each candidate component modification material, including: establishing a mapping relationship between a two-dimensional parameter space and a phase structure; the two-dimensional parameter space is constructed according to the cation polarization factor and the ion potential molar ratio of the lithium element; the two-dimensional parameter space is divided into three phase regions; different phase regions in the three phase regions correspond to different crystal structure types; according to the cation polarization factor of each candidate component modification material, a point corresponding to each candidate component modification material in the two-dimensional parameter space is determined, according to the point and the mapping relationship, a target phase region corresponding to the position of the point is determined, and the phase structure of the candidate component modification material is determined based on the crystal structure type corresponding to the target phase region.

[0010] In the implementation process, the influence of the introduction of heterogeneous elements on the original crystal structure is evaluated according to the cation polarization factor, and the phase structure of each candidate component modification material is quickly and accurately predicted based on the mapping of the two-dimensional parameter space and the phase structure.

[0011] Further, in some examples, the deduplication of the three-dimensional crystal structures obtains the simplified candidate component modification materials, including: identifying redundant structures in the three-dimensional crystal structures of the plurality of candidate component modification materials through symmetry analysis, and removing the redundant structures; and determining the candidate component modification materials corresponding to the remaining three-dimensional crystal structures as the simplified candidate component modification materials.

[0012] In the above implementation process, the three-dimensional crystal structures of each candidate component modification material are deduplicated according to the symmetry deduplication method, only independent structures that are chemically different are retained, which can effectively reduce the screening amount, thereby improving the screening efficiency and reducing the screening cost.

[0013] Further, in some examples, the screening of the simplified candidate component modification materials according to the lithium ion conductivity of the simplified candidate component modification materials at room temperature and the water molecule adsorption energy of the simplified candidate component modification materials includes: for any one of the simplified candidate component modification materials, if the lithium ion conductivity of the candidate component modification material at room temperature is less than or equal to the lithium ion conductivity of the metal halide electrolyte at room temperature, or the water molecule adsorption energy of the candidate component modification material is less than or equal to the water molecule adsorption energy of the metal halide electrolyte, the candidate component modification material is excluded.

[0014] In the above implementation process, the original metal halide electrolyte at room temperature is used as a threshold value to screen out candidate component modification materials with excellent electrochemical performance, and the water molecule adsorption energy of the original metal halide electrolyte is used as a threshold value to determine candidate component modification materials that can improve air stability as effective component modification materials. In this way, the target component modification material finally screened out not only can maintain a high ion conductivity, but also can improve the reaction between the halide electrolyte and the moisture in the air, thereby improving the air stability.

[0015] Further, in some examples, the lithium ion conductivity of the simplified candidate component modified material at room temperature is calculated based on the following manner: a three-dimensional crystal structure of the simplified candidate component modified material is optimized by first-principle calculation to obtain a target ground state structure of the simplified candidate component modified material; a warming simulation of the target ground state structure is performed by ab initio molecular dynamics method, and then an annealing process of the warmed target ground state structure is simulated according to a plurality of preset annealing temperatures, and lithium ion trajectories in the annealing process are extracted; lithium ion diffusion coefficients at each annealing temperature are calculated according to the lithium ion trajectories, and a target linear relationship is constructed according to the lithium ion diffusion coefficients at each annealing temperature; the target linear relationship is a linear relationship between the diffusion coefficient of lithium ion and the inverse of temperature; the lithium ion diffusion coefficient at room temperature is obtained according to the target linear relationship, and the lithium ion conductivity of the simplified candidate component modified material at room temperature is calculated according to the lithium ion diffusion coefficient at room temperature.

[0016] In the above implementation process, a specific way of calculating the lithium ion conductivity of the component modified material at room temperature is provided.

[0017] Further, in some examples, the water molecule adsorption energy of the simplified candidate component modified material is calculated based on the following manner: a surface model of the simplified candidate component modified material is constructed, and structure optimization and energy calculation of the surface model are performed by first-principle calculation to obtain a first ground state energy; an adsorption model of the simplified candidate component modified material adsorbing water molecules is constructed, and structure optimization and energy calculation of the adsorption model are performed by first-principle calculation to obtain a second ground state energy; a water molecule model in vacuum is constructed, and structure optimization and energy calculation of the water molecule model in vacuum are performed by first-principle calculation to obtain a second ground state energy; a difference value obtained by sequentially subtracting the first ground state energy and the second ground state energy from the second ground state energy is calculated, and the difference value is determined as the water molecule adsorption energy of the simplified candidate component modified material.

[0018] In the above implementation process, a specific way of calculating the water molecule adsorption energy of the component modified material is provided.

[0019] In a second aspect, the application provides a component modified material screening device, comprising: an acquisition module configured to acquire a plurality of candidate component modified materials for a metal halide electrolyte; a prediction module configured to predict a phase structure of each candidate component modified material according to a cation polarization factor of the candidate component modified material, acquire a three-dimensional crystal structure of each candidate component modified material based on the phase structure, and perform symmetry deduplication on the three-dimensional crystal structure to obtain a simplified candidate component modified material; and a screening module configured to screen the simplified candidate component modified material according to a lithium ion conductivity of the simplified candidate component modified material at room temperature and a water molecule adsorption energy, and obtain a target component modified material.

[0020] In a third aspect, the application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor implements the steps of the method according to any one of the first aspect when executing the computer program.

[0021] In a fourth aspect, the application provides a computer readable storage medium, wherein instructions are stored on the computer readable storage medium, and when the instructions run on a computer, the computer is caused to execute the method according to any one of the first aspect.

[0022] In a fifth aspect, the application provides a computer program product, wherein when the computer program product runs on a computer, the computer is caused to execute the method according to any one of the first aspect.

[0023] In a sixth aspect, the application provides a halide electrolyte material, which is a component modified material for a metal halide electrolyte; the component modified material is screened by the method according to any one of the first aspect.

[0024] In a seventh aspect, the application provides a secondary battery, which comprises the composite solid electrolyte material according to the sixth aspect.

[0025] Other features and advantages of the application will be illustrated in the following description, or can be inferred from the description or determined without doubt, or can be known by implementing the above-mentioned technologies disclosed in the application.

[0026] In order to make the above-mentioned purposes, features and advantages of the application more obvious and easy to understand, the following preferred embodiments are specifically described in detail below, and the accompanying drawings are referred to as follows. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. It should be understood that the following drawings only show certain embodiments of the present application 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 creative work.

[0028] Figure 1 A flow chart of a component-modified material screening method provided in an embodiment of the present application;

[0029] Figure 2 The candidate component modification materials (including Li3In 0.5 Sc 0.5 Cl6、Li3In 0.5 Al 0.5 Cl6、Li 2.5 In 0.5 Zr 0.5 Cl6 and Li3InCl 4.5 F 1.5 ) schematic diagram of the cationic polarizability factor and three-dimensional crystal structure;

[0030] Figure 3 A block diagram of a component-modified material screening device provided in an embodiment of the present application;

[0031] Figure 4 This is a structural block diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0033] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0034] Metal halide electrolytes are formed by introducing high-valent metal cations into lithium halide LiX and adjusting the concentration of Li+ and vacancy to form Li a MX bA type of compound, where M is a metal element and X is a halogen element. Metal halide electrolytes have attracted much attention due to their high ionic conductivity and good mechanical properties, and are expected to help achieve high-energy-density battery systems. However, metal halides easily react with moisture in the air, hydrolyzing to produce corrosive gases, which destroy the electrolyte structure and cause a sharp drop in ion conductivity. In addition, metal halides are prone to deliquesce in humid air, forming low-conductivity hydrates, which greatly increase interfacial impedance. These wet air stability issues not only reduce the performance of solid electrolytes, but may also cause safety hazards such as internal short circuits in the battery, seriously affecting the cycle life and safety of the battery.

[0035] In order to improve the stability of metal halide solid electrolytes in wet air, they need to be modified. Through component optimization modification, that is, introducing different contents of heterogeneous metal elements M and halogen elements X, the crystal structure of the metal halide electrolyte can be optimized, thereby improving its wet air stability. At present, the screening of modification schemes to improve the stability of metal halide solid electrolytes in wet air is mainly based on trial and error. Technicians select a certain modification scheme based on experience, synthesize the corresponding metal halide solid electrolyte, and then assemble it into a full battery for testing. In order to screen out a metal halide solid electrolyte material that meets the performance requirements, it may be necessary to repeat the process hundreds of times. The operation is cumbersome and the efficiency is extremely low, which cannot meet the needs of rapid iteration of battery material research and development.

[0036] In response to the above problems, the embodiments of the present application provide a component modification material screening scheme, which predicts the phase structure of each candidate component modification material based on the cationic polarization factor, thereby obtaining the three-dimensional crystal structure of each candidate component modification material, and reducing the screening amount by deduplicating the three-dimensional crystal structure of each candidate component modification material. Then, by calculating the lithium ion conductivity and water molecule adsorption energy of the simplified candidate component modification material at room temperature, the effect of improving the wet air stability of the halide solid electrolyte is evaluated, thereby screening out effective component modification materials. In this way, component modification materials that can improve the wet air stability of metal halide solid electrolytes can be efficiently screened out, effectively improving screening efficiency and reducing screening costs, thereby meeting the rapid iteration of battery material research and development needs.

[0037] Next, the embodiments of the present application are introduced:

[0038] like Figure 1 As shown, Figure 1 This is a flow chart of a component-modified material screening method provided in an embodiment of the present application. The method can be applied to a high-performance computer capable of material simulation and design. The method includes:

[0039] Step 101: obtaining a plurality of candidate component modification materials for metal halide electrolytes;

[0040] The metal halide electrolyte mentioned in this step can be an original metal halide Li a MX b , such as Li3InCl6, Li3YCl6, and the like. The candidate component modified material mentioned in this step can be obtained by introducing s kinds of heterogeneous metal elements and / or t kinds of heterogeneous halogen elements in the metal halide electrolyte, where s≥1, t≥1. In implementation, a number of candidate component modified materials can be obtained based on the transition metal elements and halogen elements in the periodic table as a candidate range, according to experience and related theories, such as the hard and soft acid-base theory.

[0041] Step 102, predicting the phase structure of each candidate component modified material according to the cation polarization factor of each candidate component modified material, obtaining the three-dimensional crystal structure of each candidate component modified material based on the phase structure, and deduplicating the three-dimensional crystal structure to obtain the simplified candidate component modified material;

[0042] In the embodiment scheme, the phase structure of the candidate component modification is predicted based on the cation polarization factor. The cation polarization factor here is a parameter used to describe the structure design of the metal halide solid-state electrolyte, and the stacking structure is predicted through geometric conditions and ion conditions.

[0043] In some embodiments, the cation polarization factor of the candidate component modified material mentioned in this step can be calculated according to the ion potential molar ratio of lithium elements, metal elements, and halogen elements in the candidate component modified material, and a target proportionality coefficient; the ion potential molar ratio is the sum of the proportion of the atomic number and the ion radius of the corresponding element; and the target proportionality coefficient is determined according to the valence and atomic number of the heterogeneous metal elements introduced by the candidate component modified material.

[0044] That is, the names of the s kinds of heterogeneous metal elements introduced by any one candidate component modified material are M (1) , M (2) , …, M (s) , the valence is +m1, +m2, …, +m s , the atomic number is x1, x2, …, x s , and / or the names of the t kinds of heterogeneous halogen elements introduced by the candidate component modified material are X (1) , X (2) , …, X (t) , the atomic number is y1, y2, …, y t , then the ion potential molar ratio of lithium elements φ Li , the ion potential molar ratio of metal elements ∑φ M , and the ion potential molar ratio of halogen elements ∑φ XThe calculation process is as follows:

[0045] The atomic number of lithium element is calculated according to the valence state balance, and is denoted as a+a ′ , a is the atomic number of lithium element in the original metal halide, wherein m is the valence state of the metal element in the original metal halide; the ionic radius r of lithium element is obtained by looking up the table Li , then the ionic potential molar ratio of lithium element is calculated

[0046] The ionic radius r of each metal element is obtained by looking up the table M , , then the ionic potential molar ratio of the metal element is calculated

[0047] The ionic radius r of each halogen element is obtained by looking up the table X , , then the ionic potential molar ratio of the metal element is calculated wherein b is the atomic number of halogen element in the original metal halide.

[0048] Then, the cation polarization factor of each candidate component modification material is calculated according to the ionic potential molar ratio of lithium element, metal element and halogen element wherein k is a proportional coefficient related to the valence state and atomic number of s kinds of heterogeneous metal elements introduced, which can be fitted according to existing data, and when the valence states of all heterogeneous metal elements are the same as that of the original metal element M, k = 1. In this way, the cation polarization factor of each candidate component modification material can be accurately calculated, which lays a good foundation for subsequent prediction of the phase structure of each component modification material.

[0049] In some embodiments, the prediction of the phase structure of each candidate component modification material according to the cation polarization factor of each candidate component modification material in this step can include: establishing a mapping relationship between a two-dimensional parameter space and a phase structure; the two-dimensional parameter space is constructed according to the cation polarization factor and the ionic potential molar ratio of the lithium element; the two-dimensional parameter space is divided into three phase regions; different phase regions in the three phase regions correspond to different crystal structure types; according to the cation polarization factor of each candidate component modification material, the point corresponding to each candidate component modification material in the two-dimensional parameter space is determined, according to the point and the mapping relationship, the target phase region corresponding to the position of the point is determined, and the phase structure of the candidate component modification material is determined based on the crystal structure type corresponding to the target phase region.

[0050] That is, according to the cation polarization factor τ, the influence of the introduction of heterogeneous elements on the original crystal structure is evaluated, and based on {τ, φ Li} space and phase structure mapping, predicting the phase structure of each candidate component modified material, the steps may include: establishing {τ,φ based on existing calculations and physical and chemical test characterization data Li The mapping of space and phase structure is achieved through two dividing curves f1(τ,φ Li )=0 and f2(τ,φ Li )=0{τ,φ Li The space is divided into three parts, corresponding to the three phase regions of ccp-M (cubic close packing), hcp-O (orthorhombic hexagonal close packing), and hcp-T (trigonal symmetric hexagonal close packing). According to the previous calculation steps, the modified material of any candidate component is obtained in {τ,φ Li}The corresponding point in the space can determine the phase structure of the candidate component modified material based on the phase region where the point falls.

[0051] In this embodiment, after predicting the phase structure of each candidate component modification material, the corresponding three-dimensional crystal structure is obtained based on the phase structure, and the three-dimensional crystal structure of each candidate component modification material is deduplicated, thereby reducing the amount of screening. In some embodiments, the deduplication of the three-dimensional crystal structure mentioned in this step to obtain the simplified candidate component modification material may include: identifying redundant structures in the three-dimensional crystal structures of the multiple candidate component modification materials through symmetry analysis, and eliminating the redundant structures; determining the candidate component modification materials corresponding to the remaining three-dimensional crystal structures as the simplified candidate component modification materials. That is, for any three-dimensional crystal structure S1 of a candidate component modification material, an equivalent copy set is generated through symmetry operations such as rotation, mirroring, and inversion, and the three-dimensional crystal structure S2 of another candidate component modification material is compared with the equivalent copy set. If S2 belongs to the equivalent copy set, S2 is determined to be a redundant structure and S2 is eliminated. Otherwise, S2 is retained as an independent structure. In this way, the three-dimensional crystal structures of all candidate component modification materials are traversed, and finally the candidate component modification materials corresponding to all retained independent structures are determined as the simplified candidate component modification materials. In this way, the three-dimensional crystal structure of each candidate component modified material is deduplicated based on the symmetry deduplication method, and only independent structures that are chemically different in nature are retained, which can effectively reduce the screening amount, thereby improving the screening efficiency and reducing the screening cost.

[0052] Step 103 : Screen the streamlined candidate component-modified materials according to their lithium ion conductivity and water molecule adsorption energy at room temperature to obtain target component-modified materials.

[0053] In the embodiment, the material simulation and design are carried out by means of high-performance computing, the intrinsic physical and chemical properties of the candidate component modified material are calculated, the effects of improving the wet air stability of the metal halide solid-state electrolyte, especially the effects of improving the destruction of the metal halide solid-state electrolyte material structure by moisture in the air and the reaction problem of the high activity of the metal halide solid-state electrolyte to the components of the wet air are evaluated, and the effective component modified material is screened, so as to effectively improve the screening efficiency.

[0054] Specifically, in the screening, the lithium ion conductivity of the candidate component modified material at room temperature is calculated, so as to evaluate the intrinsic electrochemical performance of the candidate component modified material, and the water molecule adsorption energy of the candidate component modified material is calculated, so as to judge the interaction strength between the candidate component modified material and the water molecules and evaluate the effect of the candidate component modified material on the air stability. Here, the room temperature can be 300 K.

[0055] In some embodiments, the screening of the simplified candidate component modified material according to the lithium ion conductivity of the simplified candidate component modified material at room temperature and the water molecule adsorption energy of the simplified candidate component modified material in the step can include: for any one of the simplified candidate component modified materials, if the lithium ion conductivity of the candidate component modified material at room temperature is less than or equal to the lithium ion conductivity of the metal halide electrolyte at room temperature, or the water molecule adsorption energy of the candidate component modified material is less than or equal to the water molecule adsorption energy of the metal halide electrolyte, the candidate component modified material is excluded.

[0056] That is, the lithium ion conductivity of the original metal halide at room temperature is taken as a threshold value, and the lithium ion conductivity of the candidate component modified material at room temperature is denoted as If indicates that the intrinsic electrochemical performance of the candidate component modified material is excellent, the candidate component modified material can enter the next round of screening, and if indicates that the intrinsic electrochemical performance of the candidate component modified material is poor and is not suitable as a metal halide solid-state electrolyte modified material, the candidate component modified material is excluded. Then, the water molecule adsorption energy of the original metal halide is taken as a threshold value, and the water molecule adsorption energy of the candidate component modified material is denoted as If indicates that the candidate component modified material can improve the air stability, the candidate component modified material is determined as an effective component modified material, i.e., a target component modified material, and if It is indicated that the air stability of the candidate component modified material is poor, and the candidate component modified material is not suitable as a metal halide solid-state electrolyte modified material, and the candidate component modified material is excluded. In this way, the finally screened target component modified material can not only maintain a high ionic conductivity, but also improve the problem of reaction of the halide electrolyte with moisture in the air and then decomposition, thereby improving the air stability.

[0057] In some embodiments, the lithium ion conductivity of the candidate component modified material screened in this step at room temperature can be calculated based on the following method: the three-dimensional crystal structure of the candidate component modified material is optimized by first-principle calculation to obtain a target ground state structure of the candidate component modified material; the target ground state structure is simulated by heating using an ab initio molecular dynamics method, and then the annealing process of the target ground state structure after heating is simulated according to a plurality of preset annealing temperatures, and the lithium ion trajectory in the annealing process is extracted; the lithium ion diffusion coefficient at each annealing temperature is calculated according to the lithium ion trajectory, and a target linear relationship is constructed according to the lithium ion diffusion coefficient at each annealing temperature; the target linear relationship is a linear relationship between the diffusion coefficient of lithium ions and the reciprocal of temperature; the lithium ion diffusion coefficient at room temperature is obtained according to the target linear relationship, and the lithium ion conductivity of the candidate component modified material at room temperature is calculated according to the lithium ion diffusion coefficient at room temperature.

[0058] That is, the step of calculating the lithium ion conductivity of the candidate component modified material at room temperature may be as follows: the three-dimensional crystal structure of the candidate component modified material is optimized by first-principle calculation to obtain a stable ground state structure; the ab initio molecular dynamics (AIMD) is used for heating simulation, and the temperature is simulated from 0K to 1200K, 1000K and 800K, respectively; the ground state structure after heating is extracted, and the 10ps simulation annealing process is continued using the AIMD, and the annealing temperature is maintained at 1200K, 1000K and 800K, respectively; the lithium ion trajectory in each annealing process is extracted, for example, the lithium ion mean square displacement MSD of the candidate component modified material at the corresponding annealing temperature is calculated according to the formula , in which N is the number of diffusing ions, r i (t) is the displacement of the i th ion at time t, t0 is the initial time, and <·> is the ensemble average (multi-trajectory average) or time average (single trajectory long-time sampling); the lithium ion diffusion coefficient at 1200K, 1000K and 800K is calculated according to the formula , and is recorded as and , respectively. Liis the diffusion coefficient of lithium ion, d is the dimension of diffusion; according to Arrhenius equation, the logarithm of the left and right of the equation is taken, and the linear relationship between the logarithm of the diffusion coefficient and the reciprocal of temperature is obtained At this time, the logarithm of the diffusion coefficient and the reciprocal of temperature are linearly related, and the fitting of 1 / T and and According to the linear relationship, the diffusion coefficient of the candidate component modified material at 300K can be obtained According to the Nernst-Einstein equation, the lithium ion conductivity of the candidate component modified material at room temperature is calculated In the formula, p is the molar density of lithium ions diffusing in a unit cell, which can be obtained by calculating the ratio of the number of lithium atoms in a three-dimensional crystal structure to the total number of atoms, z is the charge of lithium ions (usually +1), F and R are Faraday constant and gas constant respectively, and T is temperature. In this formula, T = 300K. In this way, the lithium ion conductivity of the candidate component modified material at room temperature can be quickly and accurately calculated. Similarly, the lithium ion conductivity of the metal halide electrolyte at room temperature can also be calculated based on the corresponding calculation method, which will not be described herein.

[0059] In some embodiments, the water molecule adsorption energy of the simplified candidate component modified material mentioned in this step can be calculated based on the following method: constructing a surface model of the simplified candidate component modified material, performing structure optimization and energy calculation on the surface model by first-principle calculation to obtain a first ground state energy; constructing an adsorption model of water molecules adsorbed by the simplified candidate component modified material, performing structure optimization and energy calculation on the adsorption model by first-principle calculation to obtain a second ground state energy; constructing a water molecule model in vacuum, performing structure optimization and energy calculation on the water molecule model in vacuum by first-principle calculation to obtain a second ground state energy; calculating the difference obtained by sequentially subtracting the first ground state energy and the second ground state energy from the second ground state energy, and determining the difference as the water molecule adsorption energy of the simplified candidate component modified material.

[0060] That is, the steps of calculating the water molecule adsorption energy of the candidate component modified material may be as follows: constructing a surface model of the candidate component modified material, and performing structure optimization on the surface model by first-principle calculation to obtain a first ground state energy E slab ; constructing an adsorption model of water molecules adsorbed by the candidate component modified material, and performing structure optimization on the adsorption model by first-principle calculation to obtain a second ground state energy E adsorption ; constructing a water molecule model in vacuum, and performing structure optimization on the water molecule model in vacuum by first-principle calculation to obtain a third ground state energy E H20 ; calculating the water molecule adsorption energy of the candidate component modified material Thus, based on the first-principles calculation method, high-throughput calculation can efficiently and accurately evaluate the interaction strength of the candidate component modified material and water molecules. Similarly, the water molecule adsorption energy of the metal halide electrolyte can also be calculated based on the corresponding calculation method, which is not described herein.

[0061] In the embodiments of the present application, a plurality of candidate component modified materials for the metal halide electrolyte are obtained, the phase structure of each candidate component modified material is predicted according to the cation polarization factor, the three-dimensional crystal structure of each candidate component modified material is obtained based on the phase structure, and each three-dimensional crystal structure is de-duplicated to reduce the screening amount. Then, the lithium ion conductivity of the simplified candidate component modified material at room temperature and the water molecule adsorption energy are calculated to evaluate the effect of improving the electrochemical performance and the wet air stability of the metal halide electrolyte, and then the effective component modified material is screened. In this way, the screening efficiency of the component modified material for improving the wet air stability of the metal halide electrolyte is effectively improved, and the screening cost is reduced, so as to meet the rapid iteration of battery material research and development requirements.

[0062] In order to make a more detailed description of the scheme of the present application, a specific embodiment is introduced as follows:

[0063] The present embodiment provides a component modified material screening scheme for improving the wet air stability of a metal halide solid-state electrolyte. The scheme selects Li3InCl6 as the original metal halide, which has high ion conductivity and good mechanical properties, but is easy to react with water in the air, hydrolysis to produce corrosive gas, destroy the electrolyte structure, and cause the ion conduction performance to drop sharply. The scheme of the present embodiment includes:

[0064] S201, introducing a homovalent element Sc 3+ replacing 50% of In in the original metal halide Li3InCl6 3+ to obtain a candidate component modified material Li3In 0.5 Sc 0.5 Cl6, introducing a homovalent element Al 3+ replacing 50% of In in the original metal halide Li3InCl6 3+ to obtain a candidate component modified material Li3In 0.5 Al 0.5 Cl6, introducing a heterovalent element Zr 4+ replacing 50% of In in the original metal halide Li3InCl6 3+ to obtain a candidate component modified material Li 2.5 In 0.5 Zr 0.5 Cl6, and introducing a halogen element F -Replacing 25% of Cl in the original metal halide Li3InCl6 - , to obtain candidate component modified material Li3InCl 4.5 F 1.5 ;

[0065] S202, calculate the cation polarization factor of each candidate component modified material, obtain the three-dimensional crystal structure of each candidate component modified material according to the calculation result, and through symmetry analysis, remove the three-dimensional crystal structure of each candidate component modification; Specifically, the cation polarization factor and three-dimensional crystal structure of each candidate component modified material are as shown in Figure 2 Through symmetry analysis, it is determined that the three-dimensional crystal structure of each candidate component modified material is an independent structure, so the four candidate component modified materials all enter the subsequent screening step;

[0066] S203, calculate the lithium ion conductivity of the original metal halide at room temperature and the lithium ion conductivity of the candidate component modified material at room temperature to evaluate the intrinsic electrochemical performance of each candidate component modified material, and then screen each candidate component modified material; Specifically, if then the candidate component modified material enters the next round of screening; The calculation results and screening results of the lithium ion conductivity of each candidate component modified material are shown in Table 1:

[0067] Table 1, calculation results and screening results of lithium ion conductivity of each candidate component modified material

[0068]

[0069] S204, calculate the water molecule adsorption energy of the original metal halide and the water molecule adsorption energy of the candidate component modified material to evaluate the air stability of each candidate component modified material, and then screen each candidate component modified material; Specifically, if then the candidate component modified material is retained, otherwise the candidate component modified material is excluded; The calculation results and screening results of the water molecule adsorption energy of each candidate component modified material are shown in Table 2:

[0070] Table 2, calculation results and screening results of water molecule adsorption energy of each candidate component modified material

[0071]

[0072] S205, sort the screening results, from Li3In 0.5 Sc 0.5 Cl6, Li3In 0.5 Al 0.5 Cl6, Li2.5 In 0.5 Zr 0.5 Cl6、Li3InCl 4.5 F 1.5 Among the four candidate component modification materials, two effective component modification materials are screened, which are Li3In 0.5 Al 0.5 Cl6and Li 2.5 In 0.5 Zr 0.5 Cl6, these effective component modification materials have excellent electrochemical performance, and can effectively improve the problem that the metal halide solid-state electrolyte is prone to react with water molecules in the air and then decompose.

[0073] In summary, the embodiment scheme utilizes a high-performance computer for material simulation and design, evaluates the effect of improving the wet air stability of the metal halide solid-state electrolyte by calculating the intrinsic physical and chemical properties of the candidate component modification material, especially the effect of improving the destruction of the metal halide solid-state electrolyte material structure by water in the air and the reaction problem of the high activity of the metal halide solid-state electrolyte to the components of the wet air, screens the effective component modification material, improves the screening efficiency, reduces the cost, and meets the rapid iteration of the battery material research and development demand.

[0074] Corresponding to the embodiments of the foregoing method, the application also provides embodiments of halide electrolyte materials and secondary batteries:

[0075] The application embodiment provides a halide electrolyte material, which is a component modification material for a metal halide electrolyte; the component modification material is screened by the method in any one of the preceding embodiments.

[0076] The halide electrolyte material has high ionic conductivity and good wet air stability. Following the previous example, the preparation method of the metal halide solid-state electrolyte Li3InCl6 includes:

[0077] S211, using anhydrous LiCl and InCl3 as raw materials, accurately weighing according to the stoichiometric ratio; the raw materials are mixed in a glove box under argon protection, and then loaded into a high-energy ball milling jar for 10 hours of mechanical alloying at 500 rpm;

[0078] S212, then pre-pressing with a cold press machine at a pressure of 150 MPa for 30 seconds;

[0079] S213, finally heating to 550℃ at a rate of 5℃ / min under argon protection in a tube furnace and keeping for 5 hours, and then grinding to obtain a solid-state electrolyte powder after furnace cooling.

[0080] The halide electrolyte material provided in this embodiment can be Li3In 0.5 Al 0.5 Cl6, the preparation method thereof is the same as that of Li3InCl6, the only difference being that ScCl3 of a corresponding stoichiometric ratio is added to the raw material; the halide electrolyte material provided in this embodiment may also be Li 2.5 In 0.5 Zr 0.5 Cl6, its preparation method is the same as that of Li3InCl6, the only difference is that ZrCl4 is added to the raw materials in a corresponding stoichiometric ratio.

[0081] An embodiment of the present application provides a secondary battery, which includes the halide electrolyte material described in the previous embodiment.

[0082] The secondary battery proposed in this embodiment has the advantages of high energy density, good cycle stability, long cycle life, etc. due to the use of the halide electrolyte material mentioned above. 0.8 Mn 0.1 Co 0.1 The composite electrode of O2 and LPSC (short for lithium phosphorus sulfur chlorine Li6PS5Cl of sulfide germanium structure) is used as the positive electrode, Li3InCl6 is used as the electrolyte layer, and the Li-In-LPSC composite electrode is used as the negative electrode to perform single-layer solid soft package assembly. The second all-solid-state lithium-ion battery is made by combining nickel manganese cobalt oxide material LiNi 0.8 Mn 0.1 Co 0.1 The composite electrode of O2 and LPSC is used as the positive electrode, Li3In 0.5 Al 0.5 Cl6 as the electrolyte layer and Li-In-LPSC composite electrode as the negative electrode to carry out single-layer solid soft package assembly; the third all-solid-state lithium-ion battery is made by combining nickel manganese cobalt oxide material LiNi 0.8 Mn 0.1 Co 0.1 The composite electrode of O2 and LPSC is used as the positive electrode, Li 2.5 In 0.5 Zr 0.5 Cl6 was used as the electrolyte layer and the Li-In-LPSC composite electrode was used as the negative electrode to assemble a single-layer solid soft package. These three all-solid-state lithium-ion batteries were subjected to room temperature electrochemical cycling at a charge and discharge rate of 0.3C. The test results are shown in Table 3:

[0083] Table 3. Test results for all-solid-state lithium-ion batteries

[0084]

[0085] As can be seen from Table 3, compared with the halide solid electrolyte without component modification, the room temperature cycle performance of the modified halide solid electrolyte is greatly improved, indicating that the damage of moisture in the air to the structure of the halide solid electrolyte material and the reaction of the high activity of the halide solid electrolyte to the components of humid air have been improved.

[0086] In addition, corresponding to the embodiments of the aforementioned method, the present application also provides embodiments of a component-modified material screening device and a terminal for its application:

[0087] Figure 3 As shown, Figure 3 : is a block diagram of a component-modified material screening device provided in an embodiment of the present application, the device comprising:

[0088] An acquisition module 31 is used to obtain a plurality of candidate component modification materials for metal halide electrolytes;

[0089] A prediction module 32 is configured to predict the phase structure of each candidate component-modified material based on the cationic polarizability factor of each candidate component-modified material, obtain the three-dimensional crystal structure of each candidate component-modified material based on the phase structure, and perform symmetry deduplication on the three-dimensional crystal structure to obtain a streamlined candidate component-modified material;

[0090] The screening module 33 is configured to screen the streamlined candidate component-modified materials according to the lithium ion conductivity and water molecule adsorption energy of the streamlined candidate component-modified materials at room temperature to obtain a target component-modified material.

[0091] The implementation process of the functions and effects of each module in the above-mentioned device is specifically described in the implementation process of the corresponding steps in the above-mentioned method, and will not be repeated here.

[0092] This application also provides an electronic device, see Figure 4 , Figure 4 This is a block diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include a processor 410, a communication interface 420, a memory 430, and at least one communication bus 440. The communication bus 440 is used to enable direct communication between these components. The communication interface 420 of the electronic device in this embodiment of the present application is used to communicate signaling or data with other node devices. The processor 410 may be an integrated circuit chip with signal processing capabilities.

[0093] The processor 410 described above can be a general processor, including a central processing unit (CPU), a network processor (NP), etc.; can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a ready programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general processor can be a microprocessor or the processor 410 can also be any conventional processor.

[0094] The memory 430 can be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read only memory (PROM), an erasable programmable read only memory (EPROM), an electrically erasable programmable read only memory (EEPROM), etc. The memory 430 stores computer readable instructions, which, when executed by the processor 410, enable the electronic device to perform the above Figure 1 The method embodiments involve various steps.

[0095] Optionally, the electronic device can further include a storage controller, an input output unit.

[0096] The memory 430, the storage controller, the processor 410, the peripheral interface, the input output unit are directly or indirectly electrically connected to each other to realize data transmission or interaction. For example, these elements can be electrically connected to each other through one or more communication buses 440. The processor 410 is configured to execute the executable modules stored in the memory 430, such as software function modules or computer programs included in the electronic device.

[0097] The input output unit is configured to provide a user with a creation task and create a selectable period or a preset execution time for starting the task to realize the interaction between the user and the server. The input output unit can be, but is not limited to, a mouse and a keyboard, etc.

[0098] It can be understood that Figure 4 The structure shown is only schematic, and the electronic device can include more or fewer components than those shown in the figure, or have different configurations from those shown in the figure. Figure 4 The structure shown is only schematic, and the electronic device can include more or fewer components than those shown in the figure, or have different configurations from those shown in the figure.Figure 4 different configurations. Figure 4 The components shown in FIG. 1 can be implemented in hardware, software, or a combination thereof.

[0099] The embodiments of the present application also provide a computer readable storage medium, wherein instructions are stored in the storage medium, and when the instructions are executed on a computer, the computer program is executed by a processor to implement the method in the method embodiments. To avoid repetition, details are not described here.

[0100] The present application also provides a computer program product, which, when executed on a computer, causes the computer to execute the method in the method embodiments.

[0101] In several embodiments provided in the present application, it should be understood that the disclosed apparatus and method can also be implemented by other means. The apparatus embodiments described above are only schematic, for example, the flowcharts and block diagrams in the drawings show the possible implementation architectures, functions and operations of the apparatus, method and computer program product according to the embodiments of the present application. In this regard, each block in the flowcharts or block diagrams can represent a module, a program segment or a part of code, which contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur in a different order than that noted in the drawings. For example, two consecutive blocks can actually be executed substantially in parallel, or they can be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and the combination of blocks in the block diagrams and / or flowcharts, can be implemented by a dedicated hardware-based system that performs the specified functions or actions, or can be implemented by a combination of special-purpose hardware and computer instructions.

[0102] In addition, each functional module in the various embodiments of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0103] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0104] The foregoing is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included within the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures.

[0105] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

[0106] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

Claims

1. A method for screening component-modified materials, characterized in that: include: Obtaining multiple candidate component modification materials for metal halide electrolytes; Predicting the phase structure of each candidate component modified material according to the cationic polarization factor of each candidate component modified material, obtaining the three-dimensional crystal structure of each candidate component modified material based on the phase structure, and removing duplicates from the three-dimensional crystal structure to obtain a streamlined candidate component modified material; The streamlined candidate component modified materials are screened according to the lithium ion conductivity and water molecule adsorption energy of the streamlined candidate component modified materials at room temperature to obtain the target component modified material.

2. The method according to claim 1, characterized in that The cationic polarization factor of the candidate component modified material is calculated based on the ionic potential molar ratio of the lithium element, metal element, and halogen element in the candidate component modified material, and the target proportional coefficient; the ionic potential molar ratio is the sum of the ratio of the atomic number of the corresponding elements to the ionic radius; the target proportional coefficient is determined based on the valence state and atomic number of the heterogeneous metal element introduced into the candidate component modified material.

3. The method according to claim 2, characterized in that The predicting of the phase structure of each candidate component modified material according to the cationic polarization factor of each candidate component modified material includes: Establishing a mapping relationship between a two-dimensional parameter space and a phase structure; the two-dimensional parameter space is constructed based on the cation polarization factor and the ion potential molar ratio of the lithium element; Dividing the two-dimensional parameter space into three phase regions; wherein different phase regions correspond to different crystal structure types; According to the cationic polarization factor of each candidate component modified material, the point corresponding to each candidate component modified material in the two-dimensional parameter space is determined, and according to the point and the mapping relationship, the target phase region corresponding to the position of the point is determined, and the phase structure of the candidate component modified material is determined based on the crystal structure type corresponding to the target phase region.

4. The method according to claim 1, wherein The method of removing duplicates from the three-dimensional crystal structure to obtain a streamlined candidate component modified material includes: identifying redundant structures in the three-dimensional crystal structures of the plurality of candidate component-modified materials through symmetry analysis, and eliminating the redundant structures; The candidate component-modified materials corresponding to the remaining three-dimensional crystal structures are determined as the streamlined candidate component-modified materials.

5. The method according to claim 1, wherein The method of screening the streamlined candidate component-modified materials according to the lithium ion conductivity and water molecule adsorption energy of the streamlined candidate component-modified materials at room temperature comprises: For any one of the simplified candidate component modification materials, if the lithium ion conductivity of the candidate component modification material at room temperature is less than or equal to the lithium ion conductivity of the metal halide electrolyte at room temperature, or the water molecule adsorption energy of the candidate component modification material is less than or equal to the water molecule adsorption energy of the metal halide electrolyte, then the candidate component modification material is excluded.

6. The method according to claim 5, characterized in that The lithium ion conductivity of the simplified candidate component modified material at room temperature is calculated based on the following method: Optimizing the three-dimensional crystal structure of the streamlined candidate component-modified material through first-principles calculations to obtain a target ground-state structure of the streamlined candidate component-modified material; Performing a temperature increase simulation on the target ground state structure using an ab initio molecular dynamics method, then simulating an annealing process of the target ground state structure after the temperature increase according to a plurality of preset annealing temperatures, and extracting lithium ion trajectories during the annealing process; Calculating the lithium ion diffusion coefficient at each annealing temperature based on the lithium ion trajectory, and then constructing a target linear relationship based on the lithium ion diffusion coefficient at each annealing temperature; the target linear relationship is a linear relationship between the lithium ion diffusion coefficient and the inverse of the temperature; According to the target linear relationship, the lithium ion diffusion coefficient at room temperature is obtained, and then the lithium ion conductivity of the simplified candidate component modified material at room temperature is calculated according to the lithium ion diffusion coefficient at room temperature.

7. The method according to claim 5, characterized in that The water molecule adsorption energy of the simplified candidate component modified material is calculated based on the following method: Constructing a surface model of the streamlined candidate component-modified material, performing structural optimization and energy calculation on the surface model using first-principles calculations to obtain a first ground-state energy; Constructing an adsorption model for water molecules adsorbed by the streamlined candidate component-modified material, performing structural optimization and energy calculation on the adsorption model using first-principles calculations to obtain a second ground-state energy; constructing a water molecule model under vacuum, performing structural optimization and energy calculation on the water molecule model under vacuum using first-principles calculations, and obtaining a second ground state energy; The difference obtained by sequentially subtracting the first ground state energy and the second ground state energy from the second ground state energy is calculated, and the difference is determined as the water molecule adsorption energy of the simplified candidate component modified material.

8. A component modified material screening device, characterized in that: include: An acquisition module, used for acquiring a plurality of candidate component modification materials for metal halide electrolytes; A prediction module, configured to predict the phase structure of each candidate component-modified material based on the cationic polarizability factor of each candidate component-modified material, obtain the three-dimensional crystal structure of each candidate component-modified material based on the phase structure, and perform symmetry deduplication on the three-dimensional crystal structure to obtain a streamlined candidate component-modified material; The screening module is used to screen the streamlined candidate component modified materials according to the lithium ion conductivity and water molecule adsorption energy of the streamlined candidate component modified materials at room temperature to obtain the target component modified material.

9. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

10. An electronic device, characterized in that: The method comprises a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

11. A halide electrolyte material, characterized in that: The halide electrolyte material is a component-modified material for a metal halide electrolyte; the component-modified material is screened by the method according to any one of claims 1 to 7.

12. A secondary battery, characterized in that: The secondary battery includes the halide electrolyte material according to claim 11.

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