A solid-state electrolyte prediction screening method and system based on an improved bond-valence potential method

Abstract

The application relates to a solid-state electrolyte prediction screening method and system based on an improved bond valence site energy method, which comprises the following steps: obtaining the crystal structure of a solid-state electrolyte, constructing a three-dimensional calculation grid of a migration ion in a unit cell by using the crystal structure, calculating a global potential energy surface by using an improved BVSE model, and determining a migration energy barrier; the improved BVSE model is obtained by introducing a Coulomb repulsion term between migration ions in an original BVSE model; identifying migration ion sites based on the global potential energy surface, calculating the site energy of each migration ion site, obtaining characteristic Coulomb repulsion energy, and performing equivalent surface analysis and simple harmonic vibration analysis to obtain an equivalent surface surrounding volume and a site vibration frequency; and comparing the migration energy barrier, the characteristic Coulomb repulsion energy, the equivalent surface surrounding volume and the site vibration frequency with preset screening criteria to screen out potential solid-state electrolyte materials. The application can promote high-throughput screening of solid-state electrolyte materials.

Description

Technical Field

[0001] This invention relates to the field of computational simulation of solid electrolyte materials and evaluation of ion transport properties, and in particular to a method and system for predicting and screening solid electrolytes based on an improved bond valence energy method. Background Technology

[0002] With the rapid development of solid-state battery technology, the demand for high-performance solid-state electrolyte materials is becoming increasingly urgent. In solid-state electrolyte systems with high concentrations of migrating ions (such as Li+ and Na+), multi-ion cooperative transport induced by Coulomb repulsion typically has a low energy barrier and is one of the key factors affecting ionic conductivity. However, current accurate assessments of cooperative transport mainly rely on time-consuming molecular dynamics (MD) simulations or kinetic Monte Carlo (KMC) simulations, lacking efficient computational methods for rapidly evaluating cooperative transport characteristics.

[0003] Meanwhile, the potential energy surface, as a fundamental physical quantity determining ion migration paths and energy landscapes, directly relates to the ease of ion hopping in terms of its local flatness. Experimental and computational studies have shown that high ionic conductivity sites in solid electrolytes typically possess large atomic displacement parameters and broad nuclear density distributions, characteristics stemming from the flattening of local potential energy surfaces. Traditional bond valence energy (BVSE) methods only consider the interaction between migrating ions and framework ions, neglecting the Coulomb repulsion between migrating ions and failing to describe cooperative transport phenomena; furthermore, their analysis focuses on the overall potential energy surface, lacking quantitative analysis of the local potential energy surface at individual migrating ion sites.

[0004] Therefore, there is an urgent need for an efficient computational method and system that can take into account the Coulomb repulsion between migrating ions and the analysis of local potential energy surfaces, so as to promote high-throughput screening of solid electrolyte materials. Summary of the Invention

[0005] To address the problems existing in the prior art, the purpose of this invention is to provide a method and system for predicting and screening solid electrolytes based on an improved bond valence energy method, so as to promote high-throughput screening of solid electrolyte materials.

[0006] To achieve the above objectives, the present invention provides the following solution: A method for predicting and screening solid electrolytes based on an improved bond valence energy approach includes: The crystal structure of the solid electrolyte is obtained, and a three-dimensional computational grid of migrating ions in the unit cell is constructed using the crystal structure. This grid is used to calculate the global state energy surface and determine the migration energy barrier using an improved BVSE model. The improved BVSE model is obtained by introducing a Coulomb repulsion term between migrating ions into the original BVSE model. Based on the global situational energy surface, the migration ion sites are identified, the site energy of each migration ion site is calculated, the characteristic Coulomb repulsion energy is obtained, and isosurface analysis and simple harmonic vibration analysis are performed to obtain the isosurface enclosed volume and site vibration frequency. The migration energy barrier, the characteristic Coulomb repulsion energy, the volume enclosed by the isosurface, and the site vibration frequency are compared with preset screening criteria to screen potential solid electrolyte materials.

[0007] Optionally, determining the migration barrier includes: The crystal space in the crystal structure is divided into three-dimensional grids at a given resolution. The BVSE potential energy value of each grid point is calculated using the improved BVSE model to construct the three-dimensional computational grid. The BVSE potential energy value corresponding to the first percolation channel penetrating the unit cell is used as the migration energy barrier.

[0008] Optionally, identifying the migrating ion sites includes: Set a target isosurface threshold, and use the target isosurface threshold to perform continuous isosurface fracturing on the global potential energy surface to obtain discrete regions; The grid point with the lowest potential energy in each discrete region is taken as the original site of the migrating ion. The coordinates of the original sites of the migrating ion are corrected by symmetry analysis, and the corrected sites are classified as non-equivalent crystallographic sites to obtain the migrating ion sites.

[0009] Optionally, obtaining the characteristic Coulomb repulsion energy includes: Calculate the site energy of each migrating ion site, pair the low-energy site with the adjacent high-energy site, calculate the Coulomb repulsion energy between the low-energy site and each high-energy site, and take the maximum Coulomb repulsion energy as the screening characteristic Coulomb repulsion energy of the low-energy site. Iterate through all the Coulomb repulsion energies of the features to be screened, and take the largest Coulomb repulsion energy of the features to be screened as the feature Coulomb repulsion energy of the crystal structure.

[0010] Optionally, obtaining the volume enclosed by the isosurface includes: Centered on the migrating ion sites, a polyhedral convex hull is constructed using coordination framework anions and used as a local region; Identify the lowest potential energy point in the local region, set an energy cutoff value based on the lowest potential energy point, extract low-energy grid points below the energy cutoff value, construct a small convex hull, and use the volume of the small convex hull as the volume enclosed by the isosurface.

[0011] Optionally, setting the energy cutoff value includes: A=E min+ k B T ; in,A This is the energy cutoff value. E min is the point where the potential energy is at its lowest. k B is the Boltzmann constant. T For temperature.

[0012] Optionally, obtaining the vibration frequency at the site includes: In the local region, the discrete potential energy data is interpolated to obtain a smooth potential energy function. At the local energy minimum, the smooth potential energy function is Taylor expanded and truncated to the second order. The target force constant matrix is ​​calculated by the central finite difference method. The target force constant matrix is ​​diagonalized to obtain the eigenvalues ​​of the force constants, which are used to calculate the vibration frequency of the site to be screened. The vibration frequency of the site with the smallest vibration frequency to be screened is taken as the site vibration frequency.

[0013] Optionally, calculating the vibration frequency of the site to be screened includes: , ; in, The vibrational frequency of the site to be screened. The eigenvalues ​​of the force constant, m For the mass of the migrating ions.

[0014] To achieve the above objectives, the present invention also provides a solid electrolyte prediction and screening system based on an improved bond valence energy method, comprising: The potential energy calculation module is used to obtain the crystal structure of the solid electrolyte, and to construct a three-dimensional computational grid of migrating ions in the unit cell using the crystal structure. This grid is used to calculate the global potential energy surface and determine the migration energy barrier using an improved BVSE model. The improved BVSE model is obtained by introducing a Coulomb repulsion term between migrating ions into the original BVSE model. The site energy analysis module is used to identify migrating ion sites based on the global site energy surface, calculate the site energy of each migrating ion site, obtain the characteristic Coulomb repulsion energy, and perform isosurface analysis and simple harmonic vibration analysis to obtain the isosurface enclosed volume and site vibration frequency. The electrolyte prediction and screening module is used to compare the migration energy barrier, the characteristic Coulomb repulsion energy, the volume enclosed by the isosurface, and the site vibration frequency with preset screening criteria to screen out potential solid electrolyte materials.

[0015] The beneficial effects of this invention are as follows: (1) This invention introduces a Coulomb repulsion term between migrating ions into the traditional BVSE method to characterize the Coulomb repulsion energy. Ec, as a cotransport descriptor, enables rapid quantitative assessment of the cotransport tendency of migrating ions in solid electrolytes using only crystal structure information, overcoming the limitations of existing technologies that rely on time-consuming and costly molecular dynamics or dynamic Monte Carlo simulations.

[0016] (2) This invention uses isosurface analysis and simple harmonic vibration analysis to analyze the spatial dimension (volume enclosed by isosurfaces). V iso) and dynamic dimension (site vibration frequency) n The site) quantitatively characterizes the flatness of the local potential energy surface at each migrating ion site, making up for the shortcomings of the traditional BVSE method, which only focuses on the global potential energy surface and cannot analyze the characteristics of the local potential energy surface.

[0017] (3) The present invention will reduce the migration barrier E b Characteristic Coulomb repulsion energy E c Volume enclosed by isosurfaces V iso and site vibration frequency n site Integrated into a unified screening framework, it can batch screen potential solid electrolyte materials from the material database through high-throughput computing and comparison with preset screening criteria, providing an efficient technical means for the rational design and accelerated discovery of solid electrolytes. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is an overall flowchart of a solid electrolyte prediction and screening method based on an improved bond valence energy method according to an embodiment of the present invention; Figure 2 This is a migrating ion co-transport descriptor for an embodiment of the present invention. E A detailed flowchart of the C calculation; Figure 3 This is a detailed flowchart of the local potential energy surface analysis according to an embodiment of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown, this embodiment discloses a method for predicting and screening solid electrolytes based on an improved bond valence energy method, including: Step 1: Introduce Coulombic repulsion between migrating ions into the traditional BVSE method to establish an improved BVSE method; Step 2: Read the crystal structure of the solid electrolyte, construct a three-dimensional computational mesh of migrating ions in the unit cell, calculate the global state energy surface using the improved BVSE method, and determine the migration energy barrier. E b ; Step 3: Identify the migrating ion sites and their site energies, and calculate the maximum Coulomb repulsion energy between high- and low-energy site pairs as the characteristic Coulomb repulsion energy of this crystal structure. E c This is used to quantitatively assess the co-transport tendency of migrating ions, such as Figure 2 As shown; Step 4: For each migrating ion site, perform isosurface analysis and simple harmonic vibration analysis to calculate the volume enclosed by the isosurface in the spatial dimension. V iso Calculating the vibration frequency of the site from a dynamic perspective n site Used to quantify the flatness of the local potential energy surface, such as Figure 3 As shown; Step 5: E c , V iso , n site and E b The ion transport performance of the material is evaluated by comparing it with the preset screening criteria.

[0023] Furthermore, the improved BVSE model divides the migrating ion potential energy into three parts: the Morse potential attraction term from the framework anion, the Coulomb repulsion term from the framework cation, and the Coulomb repulsion term from other migrating ions.

[0024] Furthermore, the method for identifying the migrating ion sites is as follows: an isosurface threshold is set on the global potential energy surface to break the continuous isosurface into discrete regions. The grid point with the lowest potential energy in each discrete region is a migrating ion original site. The coordinates of the migrating ion original sites are corrected by symmetry analysis to satisfy the symmetry of the space group to which the crystal structure belongs. The corrected sites are then classified as non-equivalent crystal degree sites to obtain accurate migrating ion sites.

[0025] Furthermore, the criteria for determining high- and low-energy sites are as follows: adjacent sites with significantly higher energy than the target site are identified as high-energy sites, while the target site itself is a low-energy site; E c The calculation method is as follows: first calculate the low-energy sites. i With each high-energy site j Coulomb repulsion energy between E c,j–i The maximum value is taken as the characteristic Coulomb repulsion energy of that site. E c,i Then, the maximum value is taken from all sites as the characteristic Coulomb repulsion energy of the crystal structure. E c .

[0026] Furthermore, the isosurface encloses the volume V iso The calculation method is as follows: a local region is defined by constructing a polyhedral convex hull using the coordinating framework anion, centered on the migrating ion site; the point of lowest potential energy is identified within the local region. E min Set the energy cutoff value to ; A=E min + k B T ( k B Boltzmann's constant, T For temperature; k B T (The Boltzmann thermal energy is approximately 0.026 eV at room temperature). Low-energy grid points below the cutoff value are extracted to construct a small convex hull. The volume of the small convex hull is then calculated. V iso .

[0027] Furthermore, the vibration frequency of the site n site The calculation method is as follows: interpolate the discrete potential energy data within a local region to obtain a smooth potential energy function. V (r); at the local energy minimum, for V(r) Perform a Taylor expansion and truncate it to the second order (harmonic approximation). Numerically calculate the 3×3 force constant matrix (Hessian matrix) using the central finite difference method. Diagonalize the Hessian matrix to obtain the three eigenvalues ​​of the force constants. l 1. l 2. l 3. Calculate the frequency in each vibration direction. , , m To determine the mass of the migrating ions, the minimum value among the three frequencies is taken as... n site .

[0028] Furthermore, the screening criteria include: migration ion co-transport criteria. E c ≥0.7eV; Local potential energy surface flatness criterion V iso ≥0.01Å 3 , n site ≤7THz; migration barrier criterion E b ≤1eV.

[0029] Furthermore, the method also includes a high-throughput calculation step: performing steps 1 to 4 in batches on a large number of crystal structure files in the material database to construct a database of ion transport properties of crystal materials, and screening potential solid electrolyte candidate materials according to the screening criteria.

[0030] In one possible implementation, this embodiment discloses a method for predicting and screening solid electrolytes based on an improved bond valence energy method, comprising: Step 1: Based on the traditional BVSE method, an improved BVSE method is established by introducing a Coulomb repulsion term between migrating ions into the model. The total potential energy of migrating ions consists of three parts: the Morse potential attraction term for framework anions, the Coulomb repulsion term for framework cations, and the Coulomb repulsion term between migrating ions. The Coulomb repulsion energy between migrating ions and the Coulomb repulsion energy of the framework adopt the same functional form, and the occupancy rate of the migrating ion sites is set to 1 to reflect the actual maximum Coulomb repulsion.

[0031] Step 2: Divide the crystal space into a three-dimensional mesh at a given resolution (usually set to 0.05–0.1 Å), calculate the BVSE potential energy value at each mesh point, and construct a three-dimensional global potential energy surface; define the energy value corresponding to the first percolation channel penetrating the unit cell as the migration barrier. E b .

[0032] Step 3: Set an isosurface threshold to break the continuous isosurface into discrete regions. The point with the lowest potential energy in each region is identified as the original site of the migrating ion. Symmetry analysis is used to correct the coordinates and classify them as non-equivalent crystallographic sites to obtain precise migrating ion sites. The site energy of each site is calculated, and low-energy sites are paired with adjacent high-energy sites. The low-energy site energy is then calculated. i With high-energy sites j Coulomb repulsion energy between E c,j–i The characteristic Coulomb repulsion energy of the site is obtained by taking the maximum value. E c,i The characteristic Coulomb repulsion energy of the crystal structure is obtained by traversing all sites and taking the maximum value. E c . E c The larger the value, the stronger the tendency of the migrating ions to migrate cooperatively.

[0033] Step 4: Using the migrating ion site as the center, construct a polyhedral convex hull with the coordination framework anion to define the local region; identify the local energy minimum. E min ,by E min + k B T To extract low-energy grid points for the truncation values, a small convex hull is generated, the volume of which is the volume enclosed by the isosurface. V iso Quantifying the flatness of the local potential energy surface from a spatial dimension. V iso A larger value indicates a flatter local potential energy surface. A Taylor expansion of the local potential energy function at its minimum, using the harmonic approximation, is performed. The 3×3 Hessian matrix is ​​calculated using the central finite difference method. After diagonalization, the three eigenvalues ​​of the force constants are obtained, and the lowest vibration frequency is selected. As a dynamic dimension descriptor n site The lower the value, the flatter the local potential energy surface.

[0034] Step 5: Calculate the results E c , V iso , n site and E b Compare with the screening criteria. If satisfied... E c ≥0.7 eV indicates that the material exhibits significant cooperative transport behavior; satisfying V iso ≥0.01Å 3 , nsite ≤7THz indicates that the local potential energy surface is sufficiently flat; satisfies E b A value ≤1 eV indicates a low migration barrier. Combining these criteria, candidate solid electrolyte materials with excellent ion transport properties can be identified.

[0035] Furthermore, a high-throughput batch calculation was performed on a large number of crystal structure files in the materials database to construct an ion transport property database. The above criteria were then used to efficiently screen potential solid electrolyte materials from the database.

[0036] In one embodiment, this embodiment needs to analyze whether a cooperative transport mechanism exists in a solid electrolyte material and characterize its local potential energy surface features. According to the present invention, a solid electrolyte prediction and screening method based on an improved bond valence energy method includes: First, obtain the crystal structure and determine the migrating ions and framework ions: using cubic garnet-type Li7La3Zr2O 12 Taking (LLZO) as an example, its crystal structure (ICSD_183607) is obtained from the ICSD database, and its space group is [missing information]. (No. 230). The migrating ion was identified as Li. + (Valence +1), the framework ion is La. 3+ Zr 4+ O 2− .

[0037] Second, calculate the global potential energy surface and determine the migration energy barrier: based on the framework ion sublattice (removing Li). + A three-dimensional mesh (approximately 2.2 million grid points) was generated with a resolution of 0.1 Å. The BVSE potential energy value of each grid point was calculated using vectorization to construct the global potential energy surface. The first permeation channel through the unit cell forms at 0.439 eV above the global minimum energy, i.e., the migration barrier. E b =0.439 eV. The percolation channel is isotropic, indicating that Li ions in LLZO have three-dimensional diffusion channels, which is beneficial for ion transport.

[0038] Third, compute the cooperative transport descriptor. E c By setting an isosurface threshold on the potential energy surface to break the continuous isosurface into discrete regions, two types of non-equivalent Li sites were identified: tetrahedral Li1 sites (site energy −1.131 eV) and octahedral Li2 sites (site energy −0.766 eV). The Li1 site is a low-energy site, with its site energy being 0.365 eV lower than that of the Li2 site. The Coulomb repulsion energy between the Li1 site and its first nearest neighbor Li2 site (distance 1.709 Å) was calculated, with a maximum value of 0.851 eV, which is the characteristic Coulomb repulsion energy of this structure.E c =0.851eV. According to E c The ≥0.7 eV criterion indicates that LLZO exhibits a significant tendency for cotransport, consistent with the conclusions of MD simulations in the literature.

[0039] Fourth, analyze the flatness of the local potential energy surface: for Li1 sites, construct a tetrahedral convex hull with coordinated O ions to identify local energy minimums. E min =−1.131eV, with E min +0.026 eV is used to truncate and extract low-energy grid points to construct a small convex hull, and the volume is calculated. V iso =0.001Å 3 Simple harmonic vibration analysis yields n site =13.635 THz. Similarly, analysis of the Li2 site yields: V iso =0.019Å3, n site =3.517 THz. The Li2 site has a large V iso With lower n site This indicates that the local potential energy surface of the octahedron is flatter, representing a superion conduction region; while the Li1 site... V iso Smaller n site The higher value indicates that the local potential energy surface of the tetrahedron is steeper, representing a rate-limiting region for ion migration. This conclusion is consistent with NMR experimental reports showing that Li ions have higher migration capabilities at octahedral sites.

[0040] Fifth, comprehensive evaluation: All LLZO descriptors satisfy the corresponding criteria, namely: E c =0.851eV≥0.7eV; V iso =0.019Å 3 ≥0.01Å 3 ; n site =3.517THz≤7THz; E b =0.439eV≤1eV. Therefore, the material exhibits excellent ion transport properties based on comprehensive evaluation.

[0041] This embodiment also provides a solid electrolyte prediction and screening system based on an improved bond valence energy method, comprising: a potential energy calculation module for obtaining the crystal structure of the solid electrolyte, constructing a three-dimensional computational grid of migrating ions in the unit cell using the crystal structure, calculating the global potential energy surface using an improved BVSE model, and determining the migration energy barrier; the improved BVSE model is obtained by introducing a Coulomb repulsion term between migrating ions into the original BVSE model; a site energy analysis module for identifying migrating ion sites based on the global potential energy surface, calculating the site energy of each migrating ion site, obtaining the characteristic Coulomb repulsion energy, and performing isosurface analysis and simple harmonic vibration analysis to obtain the isosurface enclosed volume and site vibration frequency; and an electrolyte prediction and screening module for comparing the migration energy barrier, the characteristic Coulomb repulsion energy, the isosurface enclosed volume, and the site vibration frequency with preset screening criteria to screen potential solid electrolyte materials.

[0042] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for predicting and screening solid electrolytes based on an improved bond valence energy method, characterized in that, include: The crystal structure of the solid electrolyte is obtained, and a three-dimensional computational grid of migrating ions in the unit cell is constructed using the crystal structure. This grid is used to calculate the global state energy surface and determine the migration energy barrier using an improved BVSE model. The improved BVSE model is obtained by introducing a Coulomb repulsion term between migrating ions into the original BVSE model. Based on the global situational energy surface, the migration ion sites are identified, the site energy of each migration ion site is calculated, the characteristic Coulomb repulsion energy is obtained, and isosurface analysis and simple harmonic vibration analysis are performed to obtain the isosurface enclosed volume and site vibration frequency. The migration energy barrier, the characteristic Coulomb repulsion energy, the volume enclosed by the isosurface, and the site vibration frequency are compared with preset screening criteria to screen potential solid electrolyte materials.

2. The method for predicting and screening solid electrolytes based on the improved bond valence energy method according to claim 1, characterized in that, Determining the migration barrier includes: The crystal space in the crystal structure is divided into three-dimensional grids at a given resolution. The BVSE potential energy value of each grid point is calculated using the improved BVSE model to construct the three-dimensional computational grid. The BVSE potential energy value corresponding to the first percolation channel penetrating the unit cell is used as the migration energy barrier.

3. The method for predicting and screening solid electrolytes based on the improved bond valence energy method according to claim 1, characterized in that, Identifying the migrating ion sites includes: Set a target isosurface threshold, and use the target isosurface threshold to perform continuous isosurface fracturing on the global potential energy surface to obtain discrete regions; The grid point with the lowest potential energy in each discrete region is taken as the original site of the migrating ion. The coordinates of the original sites of the migrating ion are corrected by symmetry analysis, and the corrected sites are classified as non-equivalent crystallographic sites to obtain the migrating ion sites.

4. The method for predicting and screening solid electrolytes based on the improved bond valence energy method according to claim 1, characterized in that, Obtaining the characteristic Coulomb repulsion energy includes: Calculate the site energy of each migrating ion site, pair the low-energy site with the adjacent high-energy site, calculate the Coulomb repulsion energy between the low-energy site and each high-energy site, and take the maximum Coulomb repulsion energy as the screening characteristic Coulomb repulsion energy of the low-energy site. Iterate through all the Coulomb repulsion energies of the features to be screened, and take the largest Coulomb repulsion energy of the features to be screened as the feature Coulomb repulsion energy of the crystal structure.

5. The method for predicting and screening solid electrolytes based on the improved bond valence energy method according to claim 1, characterized in that, Obtaining the volume enclosed by the isosurface includes: Centered on the migrating ion sites, a polyhedral convex hull is constructed using coordination framework anions and used as a local region; Identify the lowest potential energy point in the local region, set an energy cutoff value based on the lowest potential energy point, extract low-energy grid points below the energy cutoff value, construct a small convex hull, and use the volume of the small convex hull as the volume enclosed by the isosurface.

6. The method for predicting and screening solid electrolytes based on the improved bond valence energy method according to claim 5, characterized in that, Setting the energy cutoff value includes: A=E my+ k B T ; in, A This is the energy cutoff value. E min is the point where the potential energy is at its lowest. k B is the Boltzmann constant. T For temperature.

7. The solid electrolyte prediction and screening method based on the improved bond valence energy method according to claim 5, characterized in that, Obtaining the vibration frequency at the site includes: In the local region, the discrete potential energy data is interpolated to obtain a smooth potential energy function. At the local energy minimum, the smooth potential energy function is Taylor expanded and truncated to the second order. The target force constant matrix is ​​calculated by the central finite difference method. The target force constant matrix is ​​diagonalized to obtain the eigenvalues ​​of the force constants, which are used to calculate the vibration frequency of the site to be screened. The vibration frequency of the site with the smallest vibration frequency to be screened is taken as the site vibration frequency.

8. The method for predicting and screening solid electrolytes based on the improved bond valence energy method according to claim 7, characterized in that, Calculating the vibration frequency of the site to be screened includes: ， ； in, The vibrational frequency of the site to be screened. The eigenvalues ​​of the force constant, m For the mass of the migrating ions.

9. A solid electrolyte prediction and screening system based on an improved bond valence energy method, implemented according to any one of claims 1-8, characterized in that, include: The potential energy calculation module is used to obtain the crystal structure of the solid electrolyte, and to construct a three-dimensional computational grid of migrating ions in the unit cell using the crystal structure. This grid is used to calculate the global potential energy surface and determine the migration energy barrier using an improved BVSE model. The improved BVSE model is obtained by introducing a Coulomb repulsion term between migrating ions into the original BVSE model. The site energy analysis module is used to identify migrating ion sites based on the global site energy surface, calculate the site energy of each migrating ion site, obtain the characteristic Coulomb repulsion energy, and perform isosurface analysis and simple harmonic vibration analysis to obtain the isosurface enclosed volume and site vibration frequency. The electrolyte prediction and screening module is used to compare the migration energy barrier, the characteristic Coulomb repulsion energy, the volume enclosed by the isosurface, and the site vibration frequency with preset screening criteria to screen out potential solid electrolyte materials.

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