High temperature resistant sulfide electrolyte with core-shell structure

Abstract

The application provides a high-temperature-resistant sulfide solid electrolyte with a core-shell structure, wherein the shell material contains at least lithium (Li), phosphorus (P) and sulfur (S) elements, and the material structure factor Δ is 301.5+ / -1~980+ / -1, wherein Δ={N(Li)*312.5+N(P)*346}*4, wherein N(Li) represents the atomic percentage of Li, and N(P) represents the atomic percentage of P. The application selects and designs the core and the shell respectively. Through the analysis of the material-structure-performance of the shell material, the target material with good thermal stability, good ionic conductivity and super-high thermal stability performance is quickly designed and screened out by optimizing the composition. The core material is optimized, and a material with high ionic conductivity is used. Thus, the sulfide solid electrolyte with high ionic conductivity and super-high thermal stability performance beyond liquid electrolyte is obtained.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of battery materials, and relates to a solid electrolyte, in particular to a novel high-temperature-resistant sulfide solid electrolyte material with a core-shell structure. On this basis, the novel high-temperature-resistant sulfide solid electrolyte with a core-shell structure and a solid-state battery thereof are further described. BACKGROUND

[0002] With the rapid development of science and technology and human society, lithium ion batteries are widely used in consumer electronics, medical electronics, electric vehicles, rail transportation, mobile energy storage, smart grids, aerospace and national defense and military fields due to their superior performance. However, these fields have higher requirements for the energy density, power density and safety of the battery. However, the conventional lithium ion battery has reached the "bottleneck" of energy density, and scientists in China, the United States and Japan have agreed that the energy density of a scalable lithium ion battery cannot exceed 350 W·h / Kg. Moreover, in the process of increasing the energy density, the organic liquid electrolyte, which is volatile and flammable, is prone to cause safety accidents.

[0003] Since the currently marketed lithium ion battery uses an electrolyte containing flammable organic solvents, it is necessary to install a safety device to suppress temperature rise during short circuit or to improve the structure and material for preventing short circuit. The solid-state battery using a solid-state electrolyte which is not volatile and flammable instead of the organic liquid electrolyte is one of the main solutions to solve the "bottleneck" problem of the existing lithium ion battery, which can simplify the safety device and has excellent manufacturing cost or productivity. Among them, sulfide solid electrolyte with high ionic conductivity and its solid-state electrolyte are the main development direction.

[0004] Although these sulfide solid electrolytes are not volatile and flammable, at high temperatures, sulfide solid electrolytes are not completely thermally safe, and may undergo phase transition, thermal decomposition and component volatilization, which will greatly affect the ionic conductivity of the material and seriously affect the performance of the material. More importantly, the heated sulfide solid electrolyte will still release flammable sulfur, which will produce flammable and toxic hydrogen sulfide gas in the air, causing a huge safety risk. However, there are very few research reports in this regard, and there are few research results, so it is very urgent to improve the thermal stability of sulfide solid electrolytes and develop a series of high-temperature-resistant sulfide solid electrolytes.

[0005] Meanwhile, although the applicant has developed a series of sulfide solid electrolytes with high temperature resistance, the performance thereof does not seem to reach or exceed that of conventional sulfide solid electrolytes, such as a Li-Ge-P-S-based crystal solid electrolyte system, which has an ionic conductivity of 12 mS / cm; and a Li-Si-P-S-Cl crystal solid electrolyte, which has an ionic conductivity of 25 mS / cm. Therefore, there is an urgent need to develop a sulfide solid electrolyte with ultra-high ionic conductivity and good thermal stability, and to develop a battery with high electrochemical performance, high safety, and good operation at high temperatures. SUMMARY

[0006] The present application provides a sulfide solid electrolyte with a "core-shell" structure, and the core and shell of the sulfide solid electrolyte are respectively selected and designed. Through the analysis of "material-structure-performance" of the shell material, the target material with good thermal stability, which is not easy to decompose and not easy to precipitate sulfur, and has good ionic conductivity and ultra-high thermal stability, is quickly designed and screened by optimizing the composition. At the same time, the core material is optimized, and a material with high ionic conductivity is used. Thus, the core-shell structure is jointly designed to obtain a sulfide solid electrolyte with ultra-high thermal stability and high ionic conductivity beyond liquid electrolyte.

[0007] The present application first provides a high-temperature-resistant sulfide solid electrolyte with a core-shell structure, and the shell material contains at least lithium Li, phosphorus P, and sulfur S, and the material structure factor Δ is 301.5±1~980±1, wherein Δ={N(Li)×312.5+N(P)×346}×4, wherein N(Li) represents the atomic percentage of Li, and N(P) represents the atomic percentage of P.

[0008] The shell material has a composition of Li-P-S-M, and the content of each component is 0

[0009] Preferably, the shell material structure factor Δ is 700±1 to 980±1, wherein Δ={N(Li)×312.5+N(P)×346}×4, wherein N(Li) represents the atomic percentage of Li, and N(P) represents the atomic percentage of P. The shell material element composition is Li-P-S-M, and the content of each component is 0.305≤N(Li)≤0.55, 0.12≤N(P)≤0.25, 0.33≤N(S)≤0.445, and 0.12≤N(M)≤0.2, wherein N(Li) represents the atomic percentage of Li, N(P) represents the atomic percentage of P, N(S) represents the atomic percentage of S, and N(M) represents the atomic percentage of the doping element M, and the sum of each element is 100%. The thermal decomposition temperature of the material in this range is ≥500°C.

[0010] Preferably, the doping element M in the shell material is at least one of non-metallic elements O, Se, F, Cl, Br, I, or at least one of metal elements Mg, Ca, Sr, Zn, Sc, Sb, Si, Ge, Sn, B, Al, Ga, In, Ti, Zr, V, Nb, Cu, Ni, Mn, Cr, Ag, La, Ce, Tb, Te, Pb, As, Bi, etc.

[0011] Preferably, the core material contains at least one of Li, P, S, and Ha, and Ha includes at least one of F, Cl, Br, and I; preferably, the core material contains Li, P, S, and Ha, and the molar ratio c(Ha / P) of Ha to P satisfies the following formula: 0.8≤c(Ha / P)≤2.1.

[0012] Preferably, the core material is one of Li-Y-P-C-X type crystalline sulfide solid electrolytes, wherein Y is at least one of Sn, As, Si, Ge, Sb, Ti, Cu, and Ag; C is at least one of O, S, Se, and Te; X is at least one of F, Cl, Br, and I; and the atomic molar ratio is Li:Y:P:C:X=(7-12):(0-2):(0-2):(10-12):(0-1), wherein each lower limit of the atomic ratio is not 0.

[0013] Preferably, the sulfide electrolyte with a core-shell structure in the scope of the present application does not have an exothermic peak below 450°C; or, a phase transition peak appears near 200-350°C, but no phase decomposition exothermic peak appears.

[0014] In the present application, the sulfide electrolyte with core-shell structure in the range has a strong diffraction main peak in X-ray diffraction before 2θ = 34 ± 0.5 deg, and the presented crystal main peak does not appear after 2θ = 34 ± 0.5 deg.

[0015] In the present application, the sulfide electrolyte with core-shell structure in the range has a strong diffraction main peak in X-ray diffraction before 2θ = 34 ± 0.5 deg, and the presented crystal main peak does not appear after 2θ = 34 ± 0.5 deg.

[0016] In the present application, the sulfide electrolyte with core-shell structure in the range has an ionic conductivity of not less than 3 mS / cm and an electronic conductivity of not more than 1 x 10 -10 S / cm.

[0017] In the present application, the sulfide electrolyte with core-shell structure in the range has a brightness L* value of 50.0-80.0 in the L*a*b* colorimetric system.

[0018] In the present application, the sulfide electrolyte with core-shell structure in the range has a density of 1.66-3.0 g / cm 3 .

[0019] In the present application, the sulfide electrolyte with core-shell structure in the range has a shell material thickness of ≤20 μm; preferably ≤10 μm.

[0020] The present application provides a battery containing the above-mentioned sulfide electrolyte with core-shell structure.

[0021] The present application has the following beneficial effects: based on the composition of traditional sulfide solid electrolyte, the present application does not use expensive and low reserve rare elements, but uses cheap and abundant conventional elements, and through the corresponding design of the correlation between the structure factor Δ and the material thermal stability, as the basis for optimizing the proportion of the composition elements, a new material selection method and range different from traditional sulfide solid electrolyte can be obtained. The material in the selected range has high thermal stability, does not decompose and does not analyze sulfur at high temperature, and also shows good ionic conductivity, is more secure, and has more application scenarios. Using high-thermal-stability sulfide solid electrolyte to wrap high-ionic-conductivity sulfide solid electrolyte can improve both lithium ion conductivity and thermal stability. More importantly, the present application enriches the development of high-temperature-resistant sulfide solid electrolyte research, making it more suitable for high-temperature extreme environments. BRIEF DESCRIPTION OF DRAWINGS

[0022] The technical solutions of the embodiments of the present application are described in further detail below with reference to the drawings and examples. The technical solutions of the embodiments of the present application are described in further detail below with reference to the drawings and examples.

[0023] Figure 1 Structure diagram of sulfide solid electrolyte with core-shell structure of the application.

[0024] Figure 2 Preparation flow diagram of high-temperature-resistant sulfide solid electrolyte with core-shell structure of the application.

[0025] Figure 3 Structure factor Δ of high-temperature-resistant sulfide solid electrolyte with different atomic ratios and thermal decomposition temperature.

[0026] Figure 4 LiPS ternary composition diagram.

[0027] Figure 5 LiPSM quaternary composition diagram.

[0028] Figure 6 LiPS ternary composition diagram for simplified projection.

[0029] Figure 7 XRD test pattern of outer surface layer "shell" sulfide solid electrolyte material α in Example 105.

[0030] Figure 8 XRD test pattern of inner layer "core" sulfide solid electrolyte material β in Example 105.

[0031] Figure 9 XRD test pattern of high-temperature-resistant sulfide solid electrolyte material with core-shell structure in Example 105.

[0032] Figure 10 XRD test pattern of high-temperature-resistant sulfide solid electrolyte material with core-shell structure in Example 105 after high-temperature 600℃ treatment.

[0033] Figure 11 XRD test pattern of outer surface layer "shell" sulfide solid electrolyte material α in Example 105 after high-temperature 600℃ treatment.

[0034] Figure 12 DSC test pattern of high-temperature-resistant sulfide solid electrolyte with core-shell structure in Example 105.

[0035] Figure 13 XRD test pattern of sulfide solid electrolyte in Example 106 before high-temperature 800℃ treatment;

[0036] Figure 14 XRD test pattern of sulfide solid electrolyte in Example 106 after high-temperature 800℃ treatment;

[0037] Figure 15DSC test pattern of the high-temperature-resistant sulfide solid-state electrolyte with core-shell structure in Example 106. DETAILED DESCRIPTION

[0038] The application will be further described below by means of the accompanying drawings and specific examples, but it should be understood that these examples are only used for more detailed description and should not be understood as limiting the application in any form, i.e. not intended to limit the protection scope of the application.

[0039] I. Core-shell structure of high-temperature-resistant sulfide solid-state electrolyte

[0040] The application provides a high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure, as shown in the formula (I). Figure 1 The high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure is composed of an outer layer "shell" and an inner layer "core". The outer layer "shell" is a sulfide solid-state electrolyte material α with high thermal stability, and the inner layer "core" is a sulfide solid-state electrolyte material β with high ionic conductivity.

[0041] Both of the two layers of sulfide solid-state electrolyte have high ionic conductivity, and the sulfide solid-state electrolyte of the inner layer "core" has higher ionic conductivity, which can be up to 10-20 mS / cm, which is higher than that of liquid lithium ion electrolyte.

[0042] The high-temperature-resistant sulfide solid-state electrolyte material with a core-shell structure is obtained by the following method: Figure 2 (1) Mixing process of raw materials of the inner layer "core": using a raw material composition containing the constituent components of the inner layer "core" sulfide solid electrolyte material β, synthesizing a sulfide solid electrolyte material β precursor material by mechanical grinding or mixing under the action of a liquid phase solvent. (2) Heat treatment crystallization process of the inner layer "core" precursor: obtaining the sulfide solid-state electrolyte material β with high ionic conductivity by heating the sulfide solid electrolyte material β precursor material. (3) Coating process of raw materials of the outer layer "shell": mixing and stirring the sulfide solid-state electrolyte material β with high ionic conductivity obtained above with a raw material composition containing the constituent components of the outer layer "shell" sulfide solid electrolyte material α, synthesizing a precursor material of the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure by mechanical stirring or mixing under the action of a liquid phase solvent. (4) Sintering process of the core-shell structure: obtaining the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure by heat treatment of the precursor material of the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure obtained above. Figure 2 The preparation flowchart of the new high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure is shown.

[0043] II. Shell structure of high-temperature-resistant sulfide solid-state electrolyte

[0044] The thermal stability of the outer layer "shell" of the present application directly affects the thermal stability of the entire sulfide solid electrolyte, so for the sulfide solid electrolyte material α, a specially designed optimization core selection method for its material is designed, and a sulfide solid electrolyte material with high thermal stability is obtained according to the method.

[0045] In the microstructure of Li-P-S-M sulfide solid electrolyte α, it can be considered that a corresponding number of [Li-S] bonds and [P-S] bonds and chemical bonds of doping element M are constructed, and these bonds are further constructed into corresponding polyhedrons to construct macroscopic electrolyte materials. The material decomposition process (physically measured decomposition temperature) is closely related to the essential structure of the material, that is, closely related to the number of corresponding polyhedrons and the number of bonds that construct the electrolyte material.

[0046] Therefore, we define the structure factor δ of the sulfide solid electrolyte, which reflects the energy possessed by all polyhedrons in the sulfide solid electrolyte, or the sum of the energy of all chemical bonds (equation 1 and equation 2).

[0047]

[0048] δ = E{Li x P y S z M m} = ∑{E[LiS4]} + ∑{E[PS3] + ∑{E[PS4] + ∑{E[P2S7] + ∑{E[P2S6]} + ∑{E[M]} (2)

[0049] In equation 1 and equation 2, E{Li x P y S z M m} represents the energy value possessed by Li x P y S z M m , E[Li-S] represents the energy contained in the [Li-S] bond, E[P-S] represents the energy contained in the [P-S] bond, E[M] represents the energy contained in the chemical bond constructed by the doping element M, and E[LiS4], E[PS3], E[PS4], E[P2S7], E[P2S6] respectively represent the energy contained in the [LiS4], [PS3], [P2S7], [PS4] and [P2S6] polyhedron.

[0050] Because the purpose of introducing the doping element M is to improve the ionic conductivity, the overall proportion is as far as possible not to be damaged, the overall energy of the material is less affected, and the E[M] part of the energy can be ignored in the subsequent calculation, so as to facilitate the simplification of the model. Further, the number of [Li-S] bonds and [P-S] bonds can be estimated by polyhedron, so as to simplify equation 2 to equation 3.

[0051]

[0052] In order to compare with each other, take unit mole as a benchmark, and carry out normalization. We define the structure factor Δ of the normalized sulfide solid electrolyte, which is obtained after the unit of δ is normalized, and reflects the energy possessed by all polyhedrons in the unit of sulfide solid electrolyte, or the total sum of all bond energies.

[0053]

[0054] In equation 3 and equation 4, N[LiS4], N[PS3], N[P2S7], N[PS4] and N[P2S6] represent the number of [LiS4], [PS3], [P2S7], [PS4] and [P2S6] polyhedrons respectively, and E[LiS4], E[PS3], E[PS4], E[P2S7], E[P2S6] represent the energy contained in [LiS4], [PS3], [P2S7], [PS4] and [P2S6] polyhedrons respectively. Total The total number of atoms in the unit cell is referred to as N, which is used as a normalization coefficient to make a fair comparison between various systems with different unit cell sizes. In order to further simplify the calculation, the number of atoms of the doping element M can be ignored in the calculation process, and N Total The sum of the number of atoms of Li, S and P is denoted as N.

[0055] The number of N[LiS4], N[PS3], N[P2S7], N[PS4] and N[P2S6] can be represented by the number of central atoms therein, for example, N[LiS4] is closely related to the number of central atoms Li, and N[PS3] is closely related to the number of central atoms P. Based on the crystal structure of sulfide electrolyte, it can be known that [P2S7], [PS3] and [P2S6] can be equivalent to two different linking modes of [PS4], and can be equivalent to the structure of [PS4] in terms of quantity. Therefore, equation 4 can be further simplified to equation 5 by multiplying the number of central atoms with the number of bonds derived from the polyhedron of the central atom. Equation 5 is conducive to quickly calculating the result without the aid of computer assistance, and improves the practicability.

[0056] Δ = {N(Li) × E[Li-S] + N(p) × E[p-S]} × 4 (5)

[0057] where N(Li) represents the atomic percentage of the central atom Li, N(P) represents the atomic percentage of the central atom P, E[Li-S] represents the energy contained in the [Li-S] bond, and E[P-S] represents the energy contained in the [P-S] bond.

[0058] E[Li-S] and E[P-S] can be obtained from the Handbook of Chemistry and Physics, so equation 5 can be further simplified as equation 6.

[0059] Δ = {N(Li) x 312.5 + N(P) x 346} x 4 (6)

[0060] where N(Li) represents the atomic percentage of the central atom Li, and N(P) represents the atomic percentage of the central atom P.

[0061] Thus, we define the structure factor Δ of the normalized sulfide solid-state electrolyte (equation 6). The structure factor Δ represents the total energy simplification of all Li-S bonds and all P-S bonds inside the sulfide solid-state electrolyte, reflecting the thermal stability of the material structure. Since the structure factor Δ is a simplified result obtained by analyzing and summarizing the “material-structure-performance” three dimensions of the sulfide solid-state electrolyte, and this result is only related to the composition of Li-P-S-M, we predict that by optimizing the composition ratio of Li-P-S-M in the sulfide solid-state electrolyte, the thermal stability of the sulfide solid-state electrolyte can be effectively improved, the sulfide solid-state electrolyte can exist stably at high temperatures without obvious thermal decomposition process and sulfur precipitation process, and has good ionic conductivity.

[0062] In the Li-P-S-M sulfide solid-state electrolyte α, the element M is at least one of non-metallic elements oxygen O, selenium Se, fluorine F, chlorine Cl, bromine Br, iodine I, or metal elements magnesium Mg, calcium Ca, strontium Sr, zinc Zn, scandium Sc, antimony Sb, silicon Si, germanium Ge, tin Sn, boron B, aluminum Al, gallium Ga, indium In, titanium Ti, zirconium Zr, vanadium V, niobium Nb, copper Cu, nickel Ni, manganese Mn, chromium Cr, silver Ag, lanthanum La, cerium Ce, terbium Tb, tellurium Te, lead Pb, arsenic As, bismuth Bi, etc.

[0063] According to the derivation process of the above equation 6, the above equation 6 is also applicable to the Li-P-S sulfide solid-state electrolyte α without containing the doping element M, which is equivalent to the M content being 0.

[0064] To verify the relationship between the structure factor Δ and the thermal stability, we selected a series of sulfide solid electrolyte materials α with different compositions containing lithium Li, phosphorus P, sulfur S, and other elements M. The sulfide solid electrolyte α with different atomic numbers is summarized in Table 1. The accurate Li and P atomic ratios of the sulfide solid electrolyte α can be obtained by ICP testing, and the structure factor Δ is calculated. The electrochemical impedance spectroscopy test (test instrument is Zahner ZenniumPro) is performed on the sulfide solid electrolyte α, and the ionic conductivity of the sulfide solid electrolyte α is also summarized in Table 1. In the calculation process of the structure factor Δ, the atomic percentage (N(P) and N(Li)) is calculated without considering the atomic number of the doping elements. Total ) is not included in the atomic number of the doping elements.

[0065] The sulfide solid electrolyte α in Table 1 is placed in a muffle furnace for heating treatment, and then the sulfide solid electrolyte α after heat treatment is tested and analyzed by powder X-ray diffraction of CuKα ray to obtain the phase decomposition temperature of the sulfide solid electrolyte α. The structure factor Δ of the high-temperature-resistant sulfide solid electrolyte α with different atomic ratios and their thermal decomposition temperatures are summarized in Figure 3 .

[0066] From the experimental results, the structure factor Δ is synchronous with the thermal decomposition temperature of the sulfide solid electrolyte α. The structure factor Δ of the present application is positively correlated with the thermal decomposition temperature (thermal stability) of the sulfide solid electrolyte α, and can be used as an important parameter for measuring the thermal stability performance of the sulfide solid electrolyte α.

[0067] Table 1: Ion conductivity and structure factor Δ of high-temperature-resistant sulfide solid electrolyte α with different atomic ratios

[0068] Chemical formula Ionic conductivity / (mS / cm) Structure factor Δ Thermal decomposition temperature °C Example 1 Li2.24P1.92S3.84Cl0.4 11.6 682.16 578 Example 2 Li3.02P1.5024S3.4776Cl0.4 7.2 731.7902 622 Example 3 Li3.8P1.0848S3.1152Cl0.4 8.7 781.4204 664 Example 4 Li4.58P0.6672S2.7528Cl0.4 8.6 831.0506 705 Example 5 Li5.2P0.2496S2.5504Cl0.4 6.9 855.6808 729 Example 6 Li2.24P1.92S3.84 7.4 682.16 580 Example 7 Li3.02P1.5024S3.4776 4.3 731.7902 623 Example 8 Li3.8P1.0848S3.1152 8.3 781.4204 665 Example 9 Li4.58P0.6672S2.7528 7.2 831.0506 708

[0069] According to the composition ratio relationship of the Li-P-S-M sulfide solid electrolyte α, we established the LiPS ternary composition diagram (4) and the LiPSM quaternary composition diagram (5), respectively. We selected a part of the region with higher structure factor Δ results in the ternary and quaternary composition diagrams (the shaded part in the figure). Since the content of the doping element M is very small, the range of the region in the quaternary composition diagram is basically consistent with the projection of the LiPS ternary phase diagram on the plane. Therefore, the quaternary composition diagram can be simplified and projected on the LiPS ternary phase diagram (4), Figure 4 and Figure 6 Figure 4 and Figure 6 ​The difference part of the middle region is caused by the difference of the additional doped element M. Since our equation 6 can be widely applied to the calculation of the structure factor Δ of ternary and quaternary composition materials, and the structure factor Δ can be positively correlated with the thermal decomposition temperature, the material composition of the region obtained by taking the union of the region with a higher structure factor Δ result.

[0070] Specifically, in this region, the structure factor Δ is 301.5±1~980±1, and the thermal decomposition temperature of the material in this region is greater than 300℃. Specifically, the LiPSM material composition of this region is 0

[0071] Further, within the above-mentioned region range, the region with a higher structure factor Δ result in the composition diagram is also selected in combination with experiments, in which the structure factor Δ is 700±1~980±1, and through verification (see the following series of examples for details), the material in this region exhibits higher thermal stability and thermal decomposition temperature, and the decomposition temperature is greater than 500℃. Specifically, the material composition of this region is 0.305

[0072] To further verify the thermal decomposition temperature of the material in the above-mentioned selected region range, we provide a summary of examples 10-104 in the region range of 0

[0073] Table 2 summarizes the ion conductivity and structure factor Δ of high-temperature-resistant sulfide solid electrolyte α with different atomic ratios

[0074]

[0075]

[0076]

[0077] III. Core structure of high-temperature-resistant sulfide solid electrolyte

[0078] The inner layer "core" is a sulfide solid electrolyte material β containing at least one of lithium Li, phosphorus P, sulfur S, and halogen Ha, wherein the halogen includes at least one of fluorine F, chlorine Cl, bromine Br, and iodine I, has a diffraction peak A at 2θ = 25.5 ± 0.5 deg and a diffraction peak B at 29.8 ± 0.5 deg in powder X-ray diffraction using CuKα rays, and the molar ratio c(Ha / P) of the halogen to phosphorus satisfies the following formula: 0.8 < c(Ha / P) < 2.1.

[0079] Further, the inner layer "core" sulfide solid electrolyte material β is one of the crystal sulfide solid electrolyte materials of the formula Li-Y-P-C-X, wherein Y is at least one of tin Sn, arsenic As, silicon Si, germanium Ge, antimony Sb, titanium Ti, copper Cu, and silver Ag; C is at least one of oxygen O, sulfur S, selenium Se, and tellurium Te; and X is at least one of fluorine F, chlorine Cl, bromine Br, and iodine I. The atomic molar ratio is Li:Y:P:C:X = (7-12):(0-2):(0-2):(10-12):(0-1), wherein each lower limit of the atomic ratio is not 0. In X-ray diffraction measurement using Cu-Kα rays, in the vicinity of 2θ = 28°-31°, the peaks at 2θ = 28.7° ± 0.5° and 2θ = 29.5° ± 0.5° are two main characteristic peaks, and the peak at 2θ = 29.5° ± 0.5° is the strongest peak. In the vicinity of 2θ = 19.5°-21°, the peak at 2θ = 20.1° ± 0.5° is a characteristic peak and a less strong peak. In the vicinity of 2θ = 23.5°-24.5°, the peak at 2θ = 23.6° ± 0.5° is a characteristic peak.

[0080] IV. High-temperature-resistant sulfide solid electrolyte with core-shell structure

[0081] Example 105

[0082] For the purpose of full solid battery practicality, in combination with ionic conductivity and electrochemical stability, the preferred outer layer "shell" of the present embodiment is a sulfide solid electrolyte containing lithium Li, phosphorus P, and sulfur S, and has a sulfide solid electrolyte material α with the following atomic numbers, wherein the atomic numbers are N(Li) = 0.392, N(P) = 0.148, and N(S) = 0.46.

[0083] The preferred inner layer "core" of the present embodiment is a sulfide solid electrolyte containing lithium Li, phosphorus P, sulfur S, and chlorine Cl, with a chemical formula of Li6P1.2S5.4Cl1.2.

[0084] The high-thermal-stability sulfide solid electrolyte material α and the high-ionic-conductivity sulfide solid electrolyte material β obtained by the above method, and a core-shell structure constructed from the two electrolytes, can achieve high ionic conductivity and high thermal stability, and balanced overall performance.

[0085] Preparation method: The synthesis method of the high-temperature-resistant sulfide solid electrolyte with a core-shell structure in the present patent adopts a multi-step solid-phase sintering method, which mainly includes four steps. In the first step, the mixing process of the inner layer "core" raw materials: a raw material composition containing the constituent components of the inner layer "core" sulfide solid electrolyte material β is used to synthesize a sulfide solid electrolyte material β precursor material through mechanical grinding or mixing in a liquid phase solvent. In the second step, the inner layer "core" precursor heat treatment crystallization process: the sulfide solid electrolyte material β precursor material is heated to obtain the high-ionic-conductivity sulfide solid electrolyte material β. In the third step, the outer surface layer "shell" raw material coating process: the high-ionic-conductivity sulfide solid electrolyte material β obtained above is mixed with a raw material composition containing the constituent components of the outer surface layer "shell" sulfide solid electrolyte material α, and a precursor material of a high-temperature-resistant sulfide solid electrolyte with a core-shell structure is synthesized through mechanical stirring or mixing in a liquid phase solvent. In the fourth step, the sintering process of the core-shell structure: the precursor material of the high-temperature-resistant sulfide solid electrolyte with a core-shell structure obtained above is subjected to heat treatment to obtain the high-temperature-resistant sulfide solid electrolyte with a core-shell structure.

[0086] The synthesis method of the present embodiment is mainly using lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5), lithium chloride (LiCl) and other lithium sources, sulfur sources and chlorine sources as starting materials. These powders are weighed in the glove box under Ar environment (dew point -70°C), mixed in the agate mortar to obtain the raw precursor. Then, the obtained raw precursor is put into a 45ml zirconia jar, further put into zirconia balls (φ10mm, 15-20), and the jar is completely sealed (Ar environment). The jar is installed in a planetary ball mill, and mechanical grinding is carried out at 250-300rpm for 20-30h to obtain the precursor of the new sulfide solid electrolyte. By heating the precursor material, the heating temperature is 150-300°C, and the heat treatment time is 10-30h to obtain the sulfide solid electrolyte material β (inner layer "core") Li6P1.2S5.4Cl1.2 with high ionic conductivity. The raw materials required for the sulfide solid electrolyte material α with high thermal stability are weighed, in which lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5), sulfur and other lithium sources, sulfur sources are used as starting materials. The sulfide solid electrolyte material β obtained above with high ionic conductivity is mixed and stirred with the raw material composition containing the constituent components of the outer layer "shell" sulfide solid electrolyte material α to obtain the sulfide solid electrolyte material β with the "shell" raw material coated by the outer layer. The precursor material of the high-temperature-resistant sulfide solid electrolyte with core-shell structure (sulfide solid electrolyte material β with the "shell" raw material coated by the outer layer) obtained above is heat treated, the heating temperature is 350-600°C, and the heat treatment time is 10-30h to obtain the high-temperature-resistant sulfide solid electrolyte with core-shell structure.

[0087] XRD diffraction test: The sample was measured by XRD in a sealed sample stage without contact with air. The 2θ position of the diffraction peak was determined by the barycentric method using the XRD analysis program JADE. The test was carried out under conventional test conditions using the general powder X-ray diffractometer (other brands are also available). Since there are differences in test parameters between different instruments, the setting parameters of the general powder X-ray diffractometer are taken as an example below: tube voltage: 36kV; tube current: 20mA; X-ray wavelength: Cu-Kα ray; detector: scintillation counter; measurement range: 2θ = 10-80deg; step width, scanning speed: 0.02deg, 1deg / min; in the process of analyzing the peak position for confirming the existence of crystal structure according to the measurement results, the XRD analysis program JADE is used to draw the baseline by cubic equation fitting, and then the peak position is calculated. Figure 7 and Figure 8XRD test patterns of the outer layer "shell" sulfide solid electrolyte material α and the inner layer "core" sulfide solid electrolyte material β in this embodiment, respectively; wherein the sulfide solid electrolyte material β has characteristic diffraction peaks at 2θ = 25.46 deg and 30.1 deg. Figure 9 XRD test patterns of the high-temperature-resistant sulfide solid electrolyte with core-shell structure are shown. The new sulfide solid electrolyte was heated in a muffle furnace to 500°C, and then tested and analyzed by powder X-ray diffraction of CuKα rays, Figure 10 XRD test patterns of the high-temperature-resistant sulfide solid electrolyte material with core-shell structure after high-temperature treatment at 600°C are shown. Figure 11 XRD test patterns of the outer layer "shell" sulfide solid electrolyte material α in this embodiment after high-temperature treatment at 600°C are shown. It can be known that the XRD diffraction peak of the high-temperature-resistant sulfide solid electrolyte with core-shell structure before heating shows a strong diffraction main peak before 2θ = 34 deg, and the crystal main peak does not appear after 2θ = 34 deg. Further, after heat treatment of the high-temperature-resistant sulfide solid electrolyte with core-shell structure and the outer layer "shell" sulfide solid electrolyte material α, the heat treatment temperature exceeds 600°C, and the XRD diffraction peak of the high-temperature-resistant sulfide solid electrolyte with core-shell structure and the outer layer "shell" sulfide solid electrolyte material α shows a crystal peak at 32.5, which belongs to crystal phase B, and the main phase is Li2PS3.

[0088] ICP test: Put the test sample sulfide solid electrolyte material α into a mortar and grind it into a fine powder, transfer it into a crucible and place it in a 105°C oven for 1 hour, and then move it into a desiccator to cool. Weigh 0.1g (accurate to 0.1mg) of the sample into a 100mL beaker, add 5mL of standard digestion solution, heat on an electric hot plate (70°C) until the sample is completely dissolved, and cool to room temperature. Transfer the sample solution into a 250mL volumetric flask, and dilute with ultrapure water to the mark, and mix well. Take 5mL of the diluted sample solution and dilute it to 50mL, i.e. dilute it 10 times. The sample solution and the diluted solution are transferred into the test instrument Thermofisher iCAP 7200 for testing, with N2 as the carrier gas, gas flow 0.5L / min, atomizer pressure 0.19Mpa, and high-frequency power 1150W. Through ICP test, the accurate Li, P atomic ratio of the sulfide solid electrolyte can be obtained, and then the structure factor Δ of the sulfide solid electrolyte is calculated at 694.8 (calculated by Δ = {N(Li) × 312.5 + N(P) × 346} × 4, where N(Li) represents the atomic percentage of Li, and N(P) represents the atomic percentage of P).

[0089] DSC test: In order to accurately obtain the thermal stability parameters of the sulfide solid electrolyte of the present embodiment, differential scanning calorimetry is used for accurate testing and evaluation. 5 mg of the sulfide solid electrolyte of the core-shell structure is added to a stainless steel container for DSC (differential scanning calorimeter) and sealed. The sealed container is set in a DSC device (Netzsch DSC214) and measured. For reference, 5 mg of Al2O3 is used, the temperature rise rate is set to 5°C / min, and the final temperature is set to 450°C. According to the results of DSC, the heat generation start temperature and the heat generation peak temperature are obtained. It is noted that the heat generation start temperature refers to the temperature at which the heat flow (Heat Flow) rises, and the heat generation peak temperature refers to the peak temperature (heat generation peak temperature) at the lowest (highest) point of Heat Flow. Figure 12 The DSC test spectrum of the high-temperature-resistant sulfide solid electrolyte with a core-shell structure; no phase transition peak of the sulfide solid electrolyte at 210-350°C was found, and no exothermic peak of phase decomposition was found, which also indicates that the thermal decomposition reaction start temperature of the sulfide solid electrolyte is more than 300°C, and it is stable within the test range.

[0090] Ion conductivity test: The sulfide solid electrolyte of the core-shell structure is tested by electrochemical impedance spectroscopy, and the test instrument is Zahner Zennium Pro. The sulfide solid electrolyte obtained in the embodiment is pressed into a sheet shape (500 MPa) to obtain a sheet with a thickness of about 1.0 mm and a diameter of 10 mm. At room temperature, the ion conductivity is calculated by two-terminal AC impedance measurement. The measurement frequency range is 100 mHz to 8 MHz, and the amplitude is 5 mV. The ion conductivity of the new sulfide solid electrolyte can be measured to be 10.5 mS / cm. Similarly, the electronic conductivity is calculated by two-terminal DC polarization measurement, and the polarization voltage is 500 mV. The electronic conductivity of the sulfide solid electrolyte of the core-shell structure can be measured to be 0.43 x 10 -10 S / cm.

[0091] Morphology observation: By observing the cross-sectional morphology of the sulfide solid electrolyte of the core-shell structure, the test instrument is FIB-SEM, and the thickness of the sulfide solid electrolyte a of the outer shell "shell" is 1 μm.

[0092] Thermal decomposition experiment: A core-shell structured sulfide solid electrolyte was sealed in a quartz tube, which was placed in the center of a muffle furnace and heated. The morphological changes of the sulfide solid electrolyte during heating were observed. By cooling one end of the quartz tube containing the sulfide solid electrolyte, the sulfur precipitation could be observed, enabling the observation of the sulfur precipitation reaction of the sulfide solid electrolyte. Through a full-process thermal decomposition experiment on the novel sulfide solid electrolyte, the results showed that the sulfur precipitation temperature of this sulfide solid electrolyte was 591℃. Furthermore, this indicates that the sulfur precipitation reaction and partial decomposition of the sulfide solid electrolyte only occur when the ambient temperature exceeds 591℃.

[0093] Density test: The density of the core-shell structured sulfide solid electrolyte was measured using a true densitometer, yielding a density of 1.79 g / cm³. 3 .

[0094] Colorimetric Testing: The whiteness of the novel core-shell structured sulfide solid electrolyte was tested using a powder whiteness meter. The powder to be tested was placed in the test chamber, and the sample was positioned at the instrument's reflection test port. The measurement interface was accessed, and the measurement button was briefly pressed to initiate the measurement. A "beep" sound was emitted by the buzzer, accompanied by flashing of the LED indicator. The flashing stopped, and the buzzer emitted another "beep," completing the colorimetric measurement of the sulfide solid electrolyte. In the L*a*b* colorimetric system, the optimal L* value for the high-temperature resistant sulfide solid electrolyte with a core-shell structure is 75.0.

[0095] Example 106

[0096] From the perspective of practical application of all-solid-state batteries, and considering ionic conductivity and electrochemical stability, the preferred outer "shell" in this embodiment is a sulfide solid electrolyte containing lithium (Li), phosphorus (P), sulfur (S), and chlorine (Cl), with the following atomic numbers: N(Li) = 0.450, N(P) = 0.249, N(S) = 0.301, and N(Cl) = 0.06. Calculations show that the structure factor Δ of this sulfide solid electrolyte is 907.11.

[0097] In this embodiment, the preferred inner "core" is a sulfide solid electrolyte containing lithium (Li), phosphorus (P), germanium (Ge), sulfur (S), and chloride (Cl), with the chemical formula Li10GeP2S11.75Cl0.5.

[0098] The high thermal stability sulfide solid electrolyte material α and the high ionic conductivity sulfide solid electrolyte material β obtained above, and a core-shell structure constructed from these two electrolytes, achieve a balance between high ionic conductivity and high thermal stability.

[0099] Preparation method: The high-temperature-resistant sulfide solid electrolyte with core-shell structure was prepared by the same procedure as in Example 105. The synthesis approach of this example is mainly to use lithium sulfide (Li2S), phosphorus pentasulfide (P2S5), sulfur, germanium sulfide (GeS2), lithium chloride (LiCl) and other lithium sources, sulfur sources, germanium sources and chlorine sources as starting materials. These powders were weighed in the glove box under Ar environment (dew point -70°C), mixed in an agate mortar to obtain the raw precursor. Then, the obtained raw precursor was put into a 45 ml zirconia jar, further put into zirconia balls (φ10 mm, 15-20), and the jar was completely sealed (Ar environment). The jar was installed in a planetary ball mill, and mechanical grinding was carried out at a disc rotation speed of 370-400 rpm for 20-30 h to obtain the precursor of the new sulfide solid electrolyte. The sulfide solid electrolyte material with high ionic conductivity β (inner layer "core") Li10GeP2S11.75Cl0.5 was obtained by heating the precursor material at a heating temperature of 150-300°C for a heat treatment time of 10-30 h. The raw materials required for the sulfide solid electrolyte material α with high thermal stability (lithium source, phosphorus source, sulfur source, chlorine source) were weighed, in which lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5), sulfur and other lithium sources, sulfur sources and chlorine sources were used as starting materials. The sulfide solid electrolyte material β with high ionic conductivity Li10GeP2S11.75Cl0.5 obtained above was mixed and stirred with the raw material composition containing the constituent components of the outer shell "shell" sulfide solid electrolyte material α to obtain the sulfide solid electrolyte material β with the outer shell coated "shell" raw material. The precursor material of the high-temperature-resistant sulfide solid electrolyte with core-shell structure obtained above (sulfide solid electrolyte material β with the outer shell coated "shell" raw material) was heat treated at a heating temperature of 450-600°C for a heat treatment time of 15-30 h to obtain the high-temperature-resistant sulfide solid electrolyte with core-shell structure.

[0100] XRD diffraction test: The XRD was measured with a sealed sample stage in a way not to contact with air. The 2θ position of the diffraction peak was determined by the barycentric method using the XRD analysis program JADE. The test was performed under the conventional test conditions using the Rigaku powder X-ray diffractometer (other brands are also possible). Since there are differences in the test parameters between different instruments, the setting parameters of the Rigaku powder X-ray diffractometer are taken as an example below: tube voltage: 36 kV; tube current: 20 mA; X-ray wavelength: Cu-Kα ray; detector: scintillation counter; measurement range: 2θ = 10-80 deg; step width, scanning speed: 0.02 deg, 1 deg / min; in the process of analyzing the peak position for confirming the presence of the crystal structure according to the measurement results, the XRD analysis program JADE was used, and the baseline was drawn using a 3rd order equation fitting, so as to obtain the peak position. Figure 13 The XRD test pattern of the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure is shown. The new sulfide solid-state electrolyte was heated in a muffle furnace to 800°C, and then tested and analyzed by powder X-ray diffraction of CuKα ray, Figure 14 The XRD test pattern of the high-temperature-resistant sulfide solid-state electrolyte material with a core-shell structure after high-temperature 800°C treatment is shown. It can be known that the XRD diffraction peak of the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure before heating shows a strong diffraction main peak before 2θ = 34 deg, and the presented crystal main peak does not appear after 2θ = 34 deg. Further, after heat treatment of the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure, the heat treatment temperature exceeds 800°C, and the XRD diffraction peak of the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure shows a crystal peak at 26.5, which belongs to the crystal phase A, and the main phase is Li2S.

[0101] ICP test: grind the test sample sulfide solid electrolyte material a into fine powder in a mortar, transfer into a crucible and place in a 105°C oven for 1 hour, and cool in a desiccator. Weigh 0.1 g (accurate to 0.1 mg) of the sample into a 100 mL beaker, add 5 mL of standard digestion solution, heat on a hot plate (70°C) until the sample is completely dissolved, and cool to room temperature. Transfer the sample solution into a 250 mL volumetric flask, and dilute to volume with ultrapure water, and mix well. Take 5 mL of the diluted sample solution and dilute to 50 mL, i.e. 10-fold dilution. The sample solution and the diluted solution are transferred into the test instrument Thermofisher iCAP 7200 for testing, with N2 as the carrier gas, gas flow 0.5 L / min, atomizer pressure 0.19 Mpa, and high-frequency power 1150 W. The accurate Li, P atomic ratio of the sulfide solid electrolyte can be obtained by ICP test, and the structure factor Δ of the sulfide solid electrolyte is calculated as 907.11 (calculated by Δ = {N(Li) x 312.5 + N(P) x 346} x 4, wherein N(Li) represents the atomic percentage of Li, and N(P) represents the atomic percentage of P).

[0102] DSC test: In order to accurately obtain the thermal stability parameters of the sulfide solid electrolyte of the present embodiment, differential scanning calorimetry is used for accurate testing and evaluation. Add 5 mg of the sulfide solid electrolyte to be tested into a stainless steel container for DSC (differential scanning calorimeter) and seal. Set the sealed container in the DSC device (Netzsch DSC214) and perform the test. For reference, use 5 mg of Al2O3, set the temperature rise rate to 5°C / min, and set the termination temperature to 450°C. According to the results of the DSC, the heat generation start temperature and the heat generation peak temperature are obtained. It should be noted that the heat generation start temperature refers to the temperature at which the heat flow (Heat Flow) rises, and the heat generation peak temperature refers to the peak temperature (heat generation peak temperature) at the lowest (highest) point of Heat Flow. Figure 15 The DSC test spectrum of the high-temperature-resistant sulfide solid electrolyte material with core-shell structure in the present embodiment; it is found that the sulfide solid electrolyte does not have a phase transition peak and does not have a heat release peak of phase decomposition, which meets the requirements of the claims, and also indicates that the thermal decomposition reaction start temperature of the sulfide solid electrolyte exceeds 300°C, and it is stable within the test range.

[0103] Ion conductivity test: The core-shell structured sulfide solid-state electrolyte was subjected to electrochemical impedance spectroscopy test, and the test instrument was Zahner Zennium Pro. The sulfide solid-state electrolyte obtained in the example was pressed into a sheet shape (500 MPa) to obtain a sheet with a thickness of about 1.0 mm and a diameter of 10 mm. The ion conductivity was calculated by two-terminal AC impedance measurement at room temperature. The frequency range was 100 mHz to 8 MHz, and the amplitude was 5 mV. The ion conductivity of the novel sulfide solid-state electrolyte was measured to be 11.9 mS / cm. Similarly, the electronic conductivity was calculated by two-terminal DC polarization measurement, and the polarization voltage was 500 mV. The electronic conductivity of the core-shell structured sulfide solid-state electrolyte was measured to be 0.59 x 10 -10 S / cm.

[0104] Morphology observation: The cross-sectional morphology of the core-shell structured sulfide solid-state electrolyte was observed by FIB-SEM, and the thickness of the sulfide solid-state electrolyte a of the outer shell was 15 μm.

[0105] Thermal decomposition experiment: The core-shell structured sulfide solid-state electrolyte was sealed in a quartz tube, and the quartz tube was placed in the central position of the muffle furnace for heating treatment. The morphology change of the sulfide solid-state electrolyte during heating was observed. By cooling one end of the quartz tube sealed with the sulfide solid-state electrolyte, the sulfur precipitation was obtained, and the observation of the sulfide solid-state electrolyte was realized. The whole process of the thermal decomposition experiment of the core-shell structured sulfide solid-state electrolyte showed that the sulfur precipitation temperature of the sulfide solid-state electrolyte was 773°C, and further, when the environmental temperature exceeded 773°C, the sulfide solid-state electrolyte would appear a sulfur precipitation reaction process, and part of the decomposition would occur.

[0106] Density test: The powder density of the core-shell structured sulfide solid-state electrolyte was tested by a true density meter, and the density was 1.98 g / cm 3 .

[0107] Colorimetric test: The whiteness of the core-shell structured sulfide solid-state electrolyte was tested by a powder whiteness meter. The powder to be tested was placed in the test cavity, and the measured sample was placed in the instrument reflection test port. The measurement interface was entered, the measurement key was pressed, the buzzer emitted a "drop" sound, and the LED indicator light flickered. When the flickering stopped, the buzzer emitted a "drop" sound again, and the colorimetric measurement of the sulfide solid-state electrolyte was completed. In the L*a*b* colorimetric system, the brightness L* value of the high-temperature-resistant sulfide solid-state electrolyte with a core-shell structure was preferably 65.0.

[0108] Examples 107-137

[0109] In order to obtain the influence of the thickness relationship between the outer layer "shell" and the inner layer "core" of the high-temperature-resistant sulfide solid electrolyte with a core-shell structure, we carried out the thickness regulation of the high-thermal-stability sulfide solid electrolyte material α of different types of outer layer "shell". Among them, the thicknesses of 15 μm, 5 μm and 1 μm were selected. Among them, the sulfide solid electrolyte material β of examples 107-132 is at least one of lithium Li, phosphorus P and sulfur S elements, and the overall level of ion conductivity is lower than that of the sulfide solid electrolyte material β containing halogen elements. Examples 122-137 are Li-Y-P-C-X type sulfide solid electrolyte material β, and the overall level of ion conductivity is higher than that of the sulfide solid electrolyte material β containing halogen elements.

[0110] Table 3 Ion conductivity and electronic conductivity of high-temperature-resistant sulfide solid electrolyte with core-shell structure

[0111]

[0112]

[0113] At the same time, it can be known from the above experimental accumulation verification that the structure factor Δ is synchronous with the thermal decomposition temperature of the sulfide solid electrolyte, and presents a positive correlation, and can be used as an important parameter for measuring the thermal stability performance of the sulfide solid electrolyte. By optimizing the composition ratio of Li-P-S in the sulfide solid electrolyte, the thermal stability of the sulfide solid electrolyte can be effectively improved, the sulfide solid electrolyte can exist stably at high temperature, there is no obvious thermal decomposition process and sulfur precipitation process, and the sulfide solid electrolyte has good ion conductivity. By optimizing the material composition ratio and controlling it within a reasonable range, a new type of high-temperature-resistant sulfide solid electrolyte can be developed. And the sulfide solid electrolyte can be used as the outer shell layer of the high-ionic-conductivity sulfide solid electrolyte, so that the sulfide solid electrolyte with a core-shell structure has high ion conductivity and high thermal stability.

[0114] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high-temperature resistant sulfide electrolyte with a core-shell structure, characterized in that, The shell material structure factor Δ is 700~980, where Δ={N(Li)×312.5+N(P)×346}×4, where N(Li) represents the atomic percentage of Li and N(P) represents the atomic percentage of P. In the calculation of the structure factor Δ, when calculating the atomic percentages (N(P) and N(Li)), the total number of atoms (NTotal) is not included in the number of atoms of the doping element.

2. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, The shell material has an elemental composition of Li-PSM, with the following content: 0.278≤N(Li)≤0.745, 0.002≤N(P)≤0.247, 0.253≤N(S)≤0.443, 0≤N(M)≤0.15, where N(Li) represents the atomic percentage of Li, N(P) represents the atomic percentage of P, N(S) represents the atomic percentage of S, and N(M) represents the atomic percentage of dopant element M. The sum of all elements is 100%. The thermal decomposition temperature of the material within the elemental composition range is ≥500℃.

3. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, The doping element M in the shell material is a non-metallic element such as oxygen (O), selenium (Se), fluorine (F), chlorine (Cl), bromine (Br), iodine (I) or magnesium (Mg), calcium (Ca), strontium (Sr), zinc (Zn), scandium (Sc), antimony (Sb), silicon (Si), germanium (Ge), tin (Sn), boron (B), aluminum (Al), gallium (Ga), indium (In), titanium (Ti), zirconium (Zr), vanadium (V), niobium (Nb), copper (Cu), nickel (Ni), manganese (Mn), chromium (Cr), silver (Ag), lanthanum (La), cerium (Ce), terbium (Tb), tellurium (Te), lead (Pb), arsenic (As), and bismuth (Bi).

4. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, The nuclear material contains at least one of lithium (Li), phosphorus (P), sulfur (S), and halogen (Ha), and the halogen includes at least one of fluorine (F), chlorine (Cl), bromine (Br), and iodine (I).

5. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, The nuclear material comprises lithium (Li), phosphorus (P), sulfur (S), and halogen (Ha). The molar ratio of halogen to phosphorus, c(Ha / P), satisfies the following formula: 0.8 < c(Ha / P) < 2.

1.

6. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, The core material is one of the Li-YPCX type crystalline sulfide solid electrolytes, wherein Y is at least one of tin Sn, arsenic As, silicon Si, germanium Ge, antimony Sb, titanium Ti, copper Cu, and silver Ag; C is at least one of oxygen O, sulfur S, selenium Se, and tellurium Te; and X is at least one of fluorine F, chlorine Cl, bromine Br, and iodine I, and the atomic molar ratio is Li:Y:P:C:X = (7~12):(0~2):(0~2):(10~12):(0~1), wherein the lower limit of each atomic ratio is not 0.

7. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, The sulfide electrolyte with a core-shell structure will not exhibit an exothermic peak below 450°C; or, it will exhibit a phase transition peak between 200 and 350°C, but will not exhibit an exothermic peak of phase decomposition. The core-shell structured sulfide electrolyte exhibits a strong diffraction peak before 2θ = 34 deg in X-ray diffraction, and the crystallization peak does not appear after 2θ = 34 deg. The core-shell structured sulfide electrolyte exhibits a crystallization peak of crystalline phase A at 2θ = 26.9 ± 0.5 deg in X-ray diffraction at temperatures above 300°C; or a crystallization peak of crystalline phase B at 2θ = 32.5 ± 0.5 deg. The core-shell structured sulfide electrolyte has an ionic conductivity of not less than 3 mS / cm and an electronic conductivity of not more than 1×10⁻⁶ mS / cm. -10 S / cm; The sulfide electrolyte with a core-shell structure, Brightness of the chromaticity system The value is between 50.0 and 80.0; The core-shell structured sulfide electrolyte has a density of 1.66~3.0 g / cm³.

8. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, Shell material thickness ≤ 20μm.

9. The high-temperature resistant sulfide electrolyte with a core-shell structure according to claim 1, characterized in that, Shell material thickness ≤ 10μm.

10. A battery containing a high-temperature resistant sulfide electrolyte with a core-shell structure as described in any one of claims 1 to 9.

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