A sulfide solid electrolyte stable to solvents and to lithium, and a preparation method and applications thereof

Abstract

The application discloses a sulfide solid electrolyte stable to solvents and lithium and a preparation method and application thereof, and belongs to the technical field of solid electrolytes. 10‑x GeP 2‑ q Sb q S 12‑w R w , wherein 0<=x<1, 0 The preparation method comprises the following steps: according to the above general formula, a stoichiometric ratio of a lithium source, a germanium source, a phosphorus source and an antimony source is weighed and mechanically mixed to obtain a precursor powder; after further high-temperature calcination treatment, natural cooling to room temperature is carried out to obtain the sulfide solid electrolyte stable to solvents and lithium. The preparation method is simple, the sulfide solid electrolyte prepared has good lithium stability, the ion conductivity still remains above 80% after solvent treatment for 40 min, and can be used for preparing full solid-state lithium secondary batteries with excellent performance.

Description

Technical Field

[0001] This invention relates to the field of solid electrolyte technology, specifically to a sulfide solid electrolyte that is stable to solvents and lithium, its preparation method, and its application. Background Technology

[0002] All-solid-state batteries are being considered as a next-generation energy storage system due to their high energy density and good safety, and their use of lithium metal as the anode promises to achieve even higher energy density. Among reported solid electrolytes, sulfide solid electrolytes exhibit high room-temperature ionic conductivity, low synthesis temperature, low interfacial impedance, and ease of densification, making them a promising solid electrolyte for various applications.

[0003] Lithium, germanium, phosphorus, sulfur (Li) 10 GeP2S 12 The sulfide solid electrolyte in this system exhibits high lithium-ion conductivity, comparable even to liquid electrolytes. However, due to the difficulty in processing solid electrolytes, a single electrolyte layer up to 1 mm thick is typically used, resulting in lower-than-expected energy density in all-solid-state batteries and poor lithium stability, hindering industrialization. Many researchers have focused on reducing the electrolyte layer thickness and improving the lithium-to-liquid interface by incorporating gel layers, thereby increasing Li-ion conductivity. 10 GeP2S 12 The application range of electrolytes. However, Li 10 GeP2S 12 Electrolytes have poor chemical stability. After being soaked in organic solvents, their electrochemical performance decreases significantly, which greatly affects their application in wet coating.

[0004] Chinese patent document CN112768757A discloses an air-stable, multi-element rare earth oxide-doped lithium-germanium-phosphorus-sulfur solid electrolyte, which includes Li 10 GeP2S 12 Doping with multi-element rare earth oxides reduces the content of bridging sulfur, thereby effectively improving the Li... 10 GeP2S 12 The air stability is good. However, the composition of the multi-element rare earth oxide in this invention is complex.

[0005] Chinese patent document CN114914527A discloses a bismuth-doped lithium-germanium-phosphorus-sulfur solid electrolyte material, with the chemical formula Li. x Ge 1-y Bi y P2S 12Wherein 10 < x < 10.5, 0 < y < 0.5, the application is to replace CeS2 with Bi2S3 in a certain stoichiometric ratio, and the replacement of Bi generates a larger unit cell structure, so that Li + The vacancies generated at the sites improve the diffusion of Li + And the conductivity of the material. SUMMARY

[0006] In view of the poor lithium stability and chemical stability of the lithium germanium phosphorus sulfur Li 10 GeP2S 12 System solid electrolyte, the application provides a sulfide solid electrolyte which is stable to solvents and lithium, has good lithium stability, is stable to various solvents, and still has an ionic conductivity of more than 80% after being treated with a solvent for 40 min, and can be used to prepare a full solid-state battery with excellent performance.

[0007] The specific technical solutions are as follows:

[0008] A sulfide solid electrolyte which is stable to solvents and lithium, has the chemical general formula Li 10-x GeP 2-q Sb q S 12-w R w , wherein 0 <= x < 1, 0 < q < 2, 0 < w < 1, and R is selected from one or more of O, F, Cl, Br and I.

[0009] Preferably, the range of x is 0 <= x < 0.3, the range of q is 0 < q < 0.2, and the range of w is 0 < w < 0.6, and under the above parameters, the sulfide solid electrolyte is more stable to solvents and lithium.

[0010] In the application, the Sb element with a larger atomic radius is used to replace the P element, so as to reduce the lattice gap size, and meanwhile, the Sb element has a lower electronegativity, the SbS4 3- Group has higher stability, can weaken the adsorption capacity or reaction capacity of the solid electrolyte material to solvent molecules, improve the stability to solvents, and further form a stable interface protection layer by doping oxygen elements or halogen elements to improve the lithium stability, so as to achieve the purpose of preparing a sulfide solid electrolyte which is stable to solvents and lithium.

[0011] The Raman spectrum of the sulfide solid electrolyte appears a SbS4 -1 Group peak at about 337 cm 3- , and a PS4 -1 Group peak at about 422 cm 3- , which proves that the Sb element successfully replaces the P element in the crystal.

[0012] The sulfide solid electrolyte, which is stable to both solvents and lithium, is mixed with a solvent in a sealed container for 40 minutes. The ionic conductivity of the dried sulfide solid electrolyte is maintained above 80%. The solvent includes at least one of toluene, chlorobenzene, xylene, p-xylene, dimethyl carbonate, N-methylformamide, dimethylacetamide, N,N-dimethylbutylamine, n-hexane, glycol dimethyl ether, dibutyl ether, ethanol, 1,2-ethylenediamine, dichloroethane, dibromomethane, anisole, triethyl phosphate, dimethyl sulfoxide, dichloromethane, 1,2-ethylenedithiol, acetonitrile, tetrahydrofuran, isopentyl ether, isopropyl ether, ethyl acetate, butyl butyrate, isopropyl ether, n-heptane, hexene, or ethyl acetate.

[0013] The present invention also provides a method for preparing the solvent- and lithium-stable sulfide solid electrolyte, specifically comprising the following steps:

[0014] (1) According to the above general formula Li 10-x GeP 2-q Sb q S 12-w R w Lithium source, germanium source, phosphorus source and antimony source in stoichiometric ratio are weighed and mechanically mixed to obtain precursor powder;

[0015] (2) The precursor powder is subjected to high-temperature calcination and then naturally cooled to room temperature to obtain the sulfide solid electrolyte that is stable to solvent and lithium.

[0016] Preferably, the lithium source is Li2S, the germanium source is GeS2, the phosphorus source is P2S5, and the antimony source is SbR3 or Sb2R3.

[0017] The mechanical mixing is carried out under a vacuum or argon atmosphere.

[0018] Preferably, in step (1), the mechanical mixing method is mechanical stirring, mechanical vibration, ultrasonic dispersion, mechanical ball milling, high-energy ball milling or roller milling, and the mixing time is 1 to 48 hours.

[0019] Preferably, in step (2), the conditions for high-temperature calcination are: inert atmosphere, 500-700℃, 0.5-24 hours.

[0020] Preferably, in step (2), the powder that has been calcined and naturally cooled to room temperature is pulverized and ground to obtain the sulfide solid electrolyte that is stable to solvents and lithium.

[0021] The application further provides application of the solvent-stable and lithium-stable sulfide solid electrolyte in a full solid-state battery.

[0022] The sulfide solid electrolyte has excellent lithium stability and solvent stability, and a battery prepared by using the sulfide solid electrolyte has good stable long cycle performance.

[0023] Compared with the prior art, the application has the following beneficial effects:

[0024] (1) The application reduces the lattice gap size and PS4 3- group electronegativity, thereby improving the solvent stability of the sulfide solid electrolyte material; meanwhile, the lithium stability is improved by forming a stable interface protection layer through doping oxygen elements or halogen elements, and the solvent-stable and lithium-stable sulfide solid electrolyte is prepared.

[0025] (2) The solvent-stable and lithium-stable sulfide solid electrolyte provided by the application has high ionic conductivity, and the highest ionic conductivity can reach 14.4*10 -3 S cm -1 , further, the lithium symmetric battery assembled by using the sulfide solid electrolyte has better stable cycle performance than the lithium symmetric battery assembled by using Li 10 GeP2S 12 , and when the current density is 0.1-5 mA cm -2 , the lithium stable cycle time can be increased to 17 times.

[0026] (3) The preparation method of the solvent-stable and lithium-stable sulfide solid electrolyte provided by the application is simple in operation, high in practicability, and convenient for large-scale production. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 Li 10 GeP2S 12 and Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte before / after immersion.

[0028] Figure 2 Li 10 GeP2S 12 and Li 9.88 GeP1.96 Sb 0.04 S 11.88 Cl 0.12 Raman spectra of sulfide solid electrolyte before / after soaking.

[0029] Figure 3 25℃, current density of 0.1 mA cm -2 Li / Li 10 GeP2S 12 / Li and Li / Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 Cycle diagram of Li / Li -2 symmetric battery, surface capacity of 0.1 mAh cm DETAILED DESCRIPTION

[0030] The present application will be further illustrated by the following examples and figures. It should be understood that these examples are only used to illustrate the present application, and are not used to limit the scope of the present application.

[0031] Example 1

[0032] (1) Li2S, P2S5, GeS2 and SbCl3 (about 4 mol%) were weighed according to the stoichiometric ratio and placed in a ball mill jar for high-energy ball milling (the atmosphere in the ball mill jar was vacuum or argon), and after ball milling for 12 hours, Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 precursor powder;

[0033] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4 ℃ / min to 680 ℃ for 8 hours, and finally cooled to room temperature, crushed and ground to obtain Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte.

[0034] (3) Performance test and battery assembly

[0035] In the glove box, 2 parts by weight of toluene were mixed with 1 part by weight of Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12The solid electrolyte powder was mixed, and after stirring and mixing in a container for 40 min, it was subjected to reduced pressure filtration at 80°C until no obvious solvent was present, then transferred to a vacuum oven and dried at 80°C for 12 h to obtain Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte powder before and after solvent treatment.

[0036] The Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte powder before and after solvent treatment was pressed into a tablet, and its room temperature ionic conductivity was tested, respectively. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 6.8 x 10 -3 S cm -1 ; after toluene treatment, the room temperature ionic conductivity was 5.6 x 10 -3 S cm -1 ;

[0037] A symmetric battery was assembled with lithium metal as the symmetric electrode, Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte as the electrolyte layer. The battery could be stably cycled for 750 h at 0.1 mA cm -2 .

[0038] Example 2

[0039] (1) Li2S, P2S5, GeS2 and SbCl3 (about 5 mol%) were weighed according to the stoichiometric ratio and placed in a ball mill jar for high-energy ball milling (the atmosphere in the ball mill jar was vacuum or argon), and the ball milling was carried out for 12 h to obtain Li 9.85 GeP 1.95 Sb 0.05 S 11.85 Cl 0.15 precursor powder;

[0040] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere (argon) at a temperature rising rate of 4°C / min to 680°C for 8 h, and finally cooled to room temperature, crushed and ground to obtain Li 9.85 GeP 1.95 Sb 0.05 S 11.85 Cl 0.15 sulfide solid electrolyte;

[0041] (3) Performance test and battery assembly

[0042] In a glove box, 2 parts by weight of isopropyl ether was mixed with 1 part by weight of Li 9.85 GeP 1.95 Sb 0.05 S 11.85 Cl 0.15 The solid electrolyte powder was mixed, and after stirring for 40 min in a container, it was subjected to reduced pressure filtration at 80°C until no obvious solvent was left. It was then transferred to a vacuum oven and dried at 80°C for 12 hours to obtain the solvent-treated Li 9.85 GeP 1.95 Sb 0.05 S 11.85 Cl 0.15 sulfide solid electrolyte powder;

[0043] The Li 9.85 GeP 1.95 Sb 0.05 S 11.85 Cl 0.15 sulfide solid electrolyte powder was pressed into a tablet, and its room temperature ionic conductivity was tested. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this example before solvent treatment was 6.8 x 10 -3 S cm -1 After isopropyl ether treatment, the room temperature ionic conductivity was 6.1 x 10 -3 S cm -1 ;

[0044] A symmetric battery was assembled with lithium metal as the symmetric electrode, Li 9.85 GeP 1.95 Sb 0.05 S 11.85 Cl 0.15 sulfide solid electrolyte as the electrolyte layer. This battery could be stably cycled for 750 hours at 0.1 mA cm -2 .

[0045] Example 3

[0046] (1) Li2S, P2S5, GeS2 and SbCl3 (about 4 mol%) were weighed according to the stoichiometric ratio and placed in a roller mill jar for mechanical roller milling (the atmosphere in the roller mill jar was vacuum or argon). After roller milling for 24 hours, Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 precursor powder was obtained.

[0047] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4°C / min to 650°C for 8 hours, and finally cooled to room temperature, crushed and ground to obtain Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte;

[0048] (3) Performance test and battery assembly

[0049] In a glove box, 2 parts by weight of tetrahydrofuran was mixed with 1 part by weight of Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 solid electrolyte powder, and after stirring and mixing in the container for 40 min, vacuum filtration was performed at 80°C until no obvious solvent was observed, and then the mixture was transferred to a vacuum oven for vacuum drying at 80°C for 12 hours to obtain solvent-treated Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte powder;

[0050] The Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte powder before and after solvent treatment was pressed into a tablet to test the room temperature ionic conductivity, and the results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 6.6 x 10 -3 S cm -1 ; After treatment with tetrahydrofuran, the room temperature ionic conductivity was 5.5 x 10 -3 S cm -1 ;

[0051] A symmetric battery was assembled with lithium metal as the symmetric electrode, Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 sulfide solid electrolyte as the electrolyte layer, and the battery could be stably cycled for 650 hours at 0.1 mA cm -2 .

[0052] Example 4

[0053] (1) According to the stoichiometric ratio, Li2S, P2S5, GeS2 and SbBr3 (about 4 mol%) were weighed and placed in a stirrer for mechanical stirring (the atmosphere in the stirrer was vacuum or argon), and after stirring for 12 hours, Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Br 0.12 precursor powder was obtained.

[0054] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature of 580°C for 6 hours at a heating rate of 4°C / min, and finally cooled to room temperature, crushed and ground to obtain Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Br 0.12 sulfide solid electrolyte.

[0055] (3) Performance test and battery assembly

[0056] In the glove box, 2 parts by weight of acetonitrile were mixed with 1 part by weight of Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Br 0.12 solid electrolyte powder, and after stirring and mixing in the container for 40 min, the mixture was subjected to reduced pressure filtration at 80°C until no obvious solvent was left, and then transferred to a vacuum oven for vacuum drying at 60°C for 12 hours to obtain solvent-treated Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Br 0.12 sulfide solid electrolyte powder.

[0057] The Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Br 0.12 sulfide solid electrolyte powder before and after solvent treatment was pressed into tablets, and their room temperature ionic conductivities were tested, respectively. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 8.5 x 10 -3 S cm -1 ; After acetonitrile treatment, the room temperature ionic conductivity was 8.2 x 10 -3 S cm -1 .

[0058] With lithium metal as the symmetrical electrode, Li 9.88 GeP 1.96 Sb 0.04 S11.88 Br 0.12 The sulfide solid electrolyte is an electrolyte layer, a symmetric battery is assembled, and the battery is cycled at 0.1 mA cm -2 and can be stably cycled for 800 hours.

[0059] Example 5

[0060] (1) Li2S, P2S5, GeS2 and Sb2O3 (about 1 mol%) were weighed according to the stoichiometric ratio and placed in a ball mill pot for high-energy ball milling (the atmosphere in the ball mill pot was vacuum or argon), and Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 The precursor powder;

[0061] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4 ℃ / min to 680 ℃ for 8 hours, and finally cooled to room temperature, crushed and ground to obtain Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 The sulfide solid electrolyte;

[0062] (3) Performance test and battery assembly

[0063] In a glove box, 2 parts by weight of hexene were mixed with 1 part by weight of Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 The solid electrolyte powder was mixed, stirred and mixed in the container for 40 min, and then vacuum filtration was performed at 80 ℃ until no obvious solvent was observed, and then transferred to a vacuum oven for vacuum drying at 80 ℃ for 12 hours to obtain Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 The sulfide solid electrolyte powder;

[0064] The Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 The sulfide solid electrolyte powder was pressed into a tablet, and its room temperature ionic conductivity was tested, and the results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 7.8 x 10 -3 S cm -1; After hexene treatment, the room temperature ionic conductivity is 7.6 x 10 -3 S cm -1 ;

[0065] With lithium metal as the symmetric electrode, Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 The sulfide solid electrolyte is used as the electrolyte layer, and a symmetric battery is assembled. The battery can be stably cycled for 3000 hours at 0.1 mA cm -2 .

[0066] Example 6

[0067] (1) Li2S, P2S5, GeS2 and SbF3 (about 3 mol%) are weighed according to the stoichiometric ratio and placed in a roller mill jar for mechanical roller milling (the atmosphere in the roller mill jar is vacuum or argon). After 24 hours of roller milling, Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 precursor powder;

[0068] (2) The precursor powder is calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4°C / min to 650°C for 8 hours. Finally, it is cooled to room temperature, crushed and ground to obtain Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 sulfide solid electrolyte.

[0069] (3) Performance testing and battery assembly

[0070] In a glove box, 2 parts by weight of N,N-dimethylbutylamine is mixed with 1 part by weight of Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 solid electrolyte powder. After stirring and mixing in the container for 40 min, vacuum filtration is performed at 80°C until there is no obvious solvent. It is transferred to a vacuum oven and vacuum dried at 80°C for 12 hours to obtain Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 sulfide solid electrolyte powder;

[0071] The Li 9.91 GeP 1.97Sb 0.03 S 11.91 F 0.09 The sulfide solid electrolyte powder was pressed into a tablet, and its room temperature ionic conductivity was tested, respectively. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in the embodiment before solvent treatment was 14.4 x 10 -3 S cm -1 After N,N-dimethylbutylamine treatment, the room temperature ionic conductivity was 13.1 x 10 -3 S cm -1 ;

[0072] With lithium metal as a symmetrical electrode, Li 9.8 Ge 0.95 Si 0.05 P2S 11.8 F 0.2 The sulfide solid electrolyte was used as an electrolyte layer to assemble a symmetrical battery. The battery can be stably cycled for 2000 hours at 0.1 mA cm -2 .

[0073] Example 7

[0074] (1) Li2S, P2S5, GeS2 and SbF3 (about 3 mol%) were weighed according to the stoichiometric ratio and placed in a stirrer for mechanical stirring (the atmosphere in the stirrer was vacuum or argon), and after stirring for 12 hours, Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 precursor powder was obtained.

[0075] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4 ℃ / min to 580 ℃ for 6 hours, and finally cooled to room temperature. After crushing and grinding, Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 sulfide solid electrolyte was obtained.

[0076] (3) Performance testing and battery assembly

[0077] In a glove box, 2 parts by weight of p-xylene was mixed with 1 part by weight of Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 solid electrolyte powder, and after stirring and mixing in the container for 40 min, vacuum filtration was carried out at 80 ℃ until no obvious solvent was observed. Then, the solvent-treated Li9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 Sulfide solid electrolyte powder;

[0078] Li before and after solvent treatment 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 The sulfide solid electrolyte powder was pressed into tablets, and its room temperature ionic conductivity was tested. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this example before solvent treatment was 14.4 × 10⁻⁶. -3 S cm -1 After treatment with xylene, the room temperature ionic conductivity is 13.0 × 10⁻⁶. -3 Scm -1 ;

[0079] Using lithium metal as the symmetrical electrode, Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 A sulfide solid electrolyte forms the electrolyte layer, and a symmetrical cell is assembled. This cell operates at 0.1 mA cm⁻¹. -2 It can be stably cycled for 2500 hours.

[0080] Example 8

[0081] (1) Weigh out Li₂S, P₂S₅, GeS₂ and Sb₂O₃ (approximately 1 mol%) according to stoichiometric ratios and place them in a ball mill jar for mechanical ball milling (the atmosphere in the ball mill jar is vacuum or argon). After ball milling for 12 hours, Li₂O₃ is obtained. 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 Precursor powder;

[0082] (2) The precursor powder was calcined in a muffle furnace under an inert atmosphere (argon) at a heating rate of 4℃ / min to 680℃ for 8 hours. After cooling to room temperature, it was pulverized and ground to obtain Li. 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 Sulfide solid electrolytes;

[0083] (3) Performance testing and battery assembly

[0084] In a glove box, 2 parts by weight of ethyl acetate and 1 part by weight of Li10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 Solid electrolyte powder was mixed, after stirring and mixing in a container for 40 min, reduced pressure filtration was carried out at 80°C until no obvious solvent, transferred to a vacuum oven at 80°C for 12 hours of vacuum drying, to obtain solvent-treated Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 sulfide solid electrolyte powder;

[0085] Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 Sulfide solid electrolyte powder was pressed into a tablet, and its room temperature ionic conductivity was tested, respectively. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 7.8 x 10 -3 S cm -1 ; After ethyl acetate treatment, the room temperature ionic conductivity was 7.4 x 10 -3 S cm -1 ;

[0086] With lithium metal as a symmetrical electrode, Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 Sulfide solid electrolyte as electrolyte layer, assemble symmetrical battery, the battery can be stably cycled at 0.1 mA cm -2 for 3000 hours.

[0087] Example 9

[0088] (1) According to the stoichiometric ratio, Li2S, P2S5, GeS2 and SbCl3 (about 6 mol%) were respectively weighed and placed in a roller mill jar for mechanical roller milling (the atmosphere in the roller mill jar was vacuum or argon), and after roller milling for 24 hours, Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 precursor powder;

[0089] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4°C / min to 650°C for 8 hours, and finally cooled to room temperature, crushed and ground to obtain Li 9.82 GeP 1.94Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte;

[0090] (3) Performance test and battery assembly

[0091] In a glove box, 2 parts by weight of butyl butyrate was mixed with 1 part by weight of Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 The solid electrolyte powder was mixed, and after stirring for 40 min in a container, the mixture was subjected to reduced pressure filtration at 80°C until no obvious solvent was left. The solvent-treated Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte powder;

[0092] The Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte powder was pressed into a tablet, and its room temperature ionic conductivity was tested, respectively. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 8.3 x 10 -3 S cm -1 ; After butyl butyrate treatment, the room temperature ionic conductivity was 8.0 x 10 -3 S cm -1 ;

[0093] A symmetric battery was assembled with lithium metal as the symmetric electrode, Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte as the electrolyte layer. The battery could be stably cycled for 750 hours at 0.1 mA cm -2 .

[0094] Example 10

[0095] (1) Li2S, P2S5, GeS2 and SbCl3 (about 6 mol%) were weighed according to the stoichiometric ratio and placed in a stirrer for mechanical stirring (the atmosphere in the stirrer was vacuum or argon), and after stirring for 12 hours, Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl0.18 precursor powder;

[0096] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature- increasing rate of 4°C / min to 580°C for 6 hours, and finally cooled to room temperature, crushed and ground to obtain Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte;

[0097] (3) Performance testing and battery assembly

[0098] In a glove box, 2 parts by weight of a mixed solution of ethyl acetate and dimethylacetamide and 1 part by weight of Li 9.82 GeP 1.92 Sb 0.06 S 11.82 Cl 0.18 solid electrolyte powder was mixed, stirred in a container for 40 min, and then subjected to reduced pressure filtration at 80°C until no obvious solvent was left, and then transferred to a vacuum oven for vacuum drying at 60°C for 12 hours to obtain solvent-treated Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte powder;

[0099] The Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte powder before and after solvent treatment was pressed into tablets, and the room temperature ionic conductivity of each was tested. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 8.5 x 10 -3 S cm -1 ; After mixed solvent treatment, the room temperature ionic conductivity was 8.1 x 10 -3 S cm -1 ;

[0100] A symmetric battery was assembled with metallic lithium as the symmetric electrode, Li 9.82 GeP 1.94 Sb 0.06 S 11.82 Cl 0.18 sulfide solid electrolyte as the electrolyte layer. The battery could be stably cycled for 800 hours at 0.1 mA cm -2 .

[0101] Example 11

[0102] (1) According to stoichiometric ratio, Li2S, P2S5, GeS2 and Sb2O3 (about 2 mol%) were weighed and put into a roller mill pot for mechanical roller milling (the atmosphere in the roller mill pot was vacuum or argon), and Li 10 GeP 1.96 Sb 0.04 S 11.94 O 0.06 precursor powder;

[0103] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4 ℃ / min to 650 ℃ for 8 hours, and finally cooled to room temperature, crushed and ground to obtain Li 10 GeP 1.96 Sb 0.04 S 11.94 O 0.06 sulfide solid electrolyte;

[0104] (3) Performance test and battery assembly

[0105] In a glove box, 2 parts by weight of chlorobenzene were mixed with 1 part by weight of Li 10 GeP 1.96 Sb 0.04 S 11.94 O 0.06 solid electrolyte powder, and after stirring and mixing in a container for 40 min, vacuum filtration was carried out at 80 ℃ until no obvious solvent was left, and then transferred to a vacuum oven for vacuum drying at 80 ℃ for 12 hours to obtain Li 10 GeP 1.96 Sb 0.04 S 11.94 O 0.06 sulfide solid electrolyte powder;

[0106] The Li 10 GeP 1.98 Sb 0.02 S 11.97 O 0.03 sulfide solid electrolyte powder before and after solvent treatment was pressed into a tablet, and its room temperature ionic conductivity was tested, respectively. The results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 7.8 x 10 -3 S cm -1 ; and after chlorobenzene treatment, the room temperature ionic conductivity was 7.3 x 10 -3 S cm -1 ;

[0107] With lithium metal as a symmetrical electrode, Li 10 GeP 1.96 Sb 0.04S 11.94 O 0.06 The sulfide solid electrolyte is an electrolyte layer, a symmetric battery is assembled, and the battery can be stably cycled for 4000 hours at 0.1 mA cm -2

[0108] Example 12

[0109] (1) Li2S, P2S5, GeS2 and SbF3 (about 3 mol%) were weighed according to the stoichiometric ratio and placed in a ball mill pot for high-energy ball milling (the atmosphere in the ball mill pot was vacuum or argon), and Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 The precursor powder;

[0110] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4 ℃ / min to 680 ℃ for 8 hours, and finally cooled to room temperature, crushed and ground to obtain Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 The sulfide solid electrolyte;

[0111] (3) Performance test and battery assembly

[0112] In a glove box, 2 parts by weight of n-heptane were mixed with 1 part by weight of Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 The solid electrolyte powder was mixed, stirred and mixed in the container for 40 min, and then vacuum filtration was carried out at 80 ℃ until no obvious solvent was observed, and then transferred to a vacuum oven for vacuum drying at 80 ℃ for 12 hours to obtain the solvent-treated Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 The sulfide solid electrolyte powder;

[0113] The Li 9.91 GeP 1.97 Sb 0.03 S 11.91 F 0.09 The sulfide solid electrolyte powder was pressed into a tablet, and its room temperature ionic conductivity was tested, and the results showed that the room temperature ionic conductivity of the sulfide solid electrolyte prepared in this embodiment before solvent treatment was 14.4×10 -3 S cm -1 ​; After treatment with n-heptane, the room temperature ionic conductivity is 13.4 x 10 -3 S cm -1 ;

[0114] With lithium metal as the symmetric electrode, Li 9.91 GeP2S 1.97 Sb 0.03 S 11.91 F 0.09 The sulfide solid electrolyte is used as the electrolyte layer, and a symmetric battery is assembled. The battery can be stably cycled for 2000 hours at 0.1 mA cm -2 .

[0115] Comparative Example 1

[0116] (1) Li2S, P2S5 and GeS2 were weighed according to the stoichiometric ratio and placed in a ball mill jar for mechanical ball milling (the atmosphere in the ball mill jar was vacuum or argon). After ball milling for 12 hours, Li 10 GeP2S 12 precursor powder was obtained.

[0117] (2) The precursor powder was calcined in a muffle furnace under inert atmosphere protection (argon) at a temperature rising rate of 4°C / min to 680°C for 8 hours. Finally, it was cooled to room temperature, crushed and ground to obtain Li 10 GeP2S 12 sulfide solid electrolyte, respectively.

[0118] (3) Performance testing and battery assembly

[0119] In a glove box, 2 parts by weight of toluene were mixed with 1 part by weight of Li 10 GeP2S 12 solid electrolyte powder. After stirring and mixing in the container for 40 min, the solvent treatment was performed at 80°C under reduced pressure until there was no obvious solvent. Then, the mixture was transferred to a vacuum oven and dried at 80°C for 12 hours to obtain the Li 10 GeP2S 12 sulfide solid electrolyte powder after solvent treatment.

[0120] The Li 10 GeP2S 12 sulfide solid electrolyte powder before and after solvent treatment was pressed into a tablet, and the room temperature ionic conductivity thereof was tested, respectively. The results show that the room temperature ionic conductivity of the Li 10 GeP2S 12 sulfide solid electrolyte prepared in the present comparative example before solvent treatment is 6.2 x 10 -3 S cm -1 ; After treatment with toluene, the room temperature ionic conductivity is 3.3 x 10 -3 S cm-1 ;

[0121] Using lithium metal as the symmetrical electrode, Li 10 GeP2S 12 A sulfide solid electrolyte forms the electrolyte layer, and a symmetrical cell is assembled. This cell operates at 0.1 mA cm⁻¹. -2 It can be stably cycled for 230 hours.

[0122] Sample Analysis

[0123] Figure 1 The figures show the AC impedance spectra of the sulfide solid electrolytes in Example 1 and Comparative Example 1 before and after solvent treatment. (Li) 10 GeP2S 12 The impedance of the sulfide solid electrolyte doubled after solvent treatment, and the calculated ionic conductivity was only 3.3 mS / cm. -1 This indicates that solvent treatment significantly reduced Li 10 GeP2S 12 The ion transport capacity of the sulfide solid electrolyte was observed; however, the impedance of the sulfide solid electrolyte prepared in Example 1 increased slightly after solvent treatment, while the ionic conductivity remained at 5.6 mS / cm. -1 This demonstrates that the modified electrolyte solvent stability is significantly improved. Furthermore, analysis of the data from the above examples shows that, after solvent treatment, the sulfide solid electrolytes prepared in Examples 1-12 exhibit significantly improved stability compared to the Li-based electrolyte in Comparative Example 1. 10 GeP2S 12 Sulfide solid electrolytes retain ionic conductivity better.

[0124] Figure 2 The images show the Raman spectra of the sulfide solid electrolytes in Example 1 and Comparative Example 1 before and after solvent treatment. (Li) 10 GeP2S 12 The Raman spectra of the sulfide solid electrolyte before and after solvent treatment, at 422 cm⁻¹ -1 PS4 appears on the left and right 3- Group peaks, PS4 after solvent treatment 3- The significant splitting of the functional group peaks indicates that the group decomposed during solvent treatment, resulting in the destruction of the crystal structure. In contrast, the sulfide solid electrolyte prepared in Example 1 showed a similar pattern in its Raman spectra before and after solvent treatment, with the peaks at 422 cm⁻¹. -1 PS4 appears on the left and right 3- Group peak, at 337 cm⁻¹ -1 SbS4 appears on the left and right 3- The functional group peaks showed no significant changes before and after solvent treatment, exhibiting excellent solvent stability; and the sulfide solid electrolytes prepared in Examples 2-12 all showed peaks around 337 cm⁻¹ in their Raman spectra before and after solvent treatment. -1SbS4 3- a peak of SbS4 group appeared at 422 cm -1 PS4 3- a peak of SbS4 group appeared, which proved that the Sb element successfully replaced the P element in the crystal and the SbS4 3- group was formed, which significantly improved the solvent stability of the sulfide solid electrolyte.

[0125] Figure 3 Li in Comparative Example 1 10 GeP2S 12 symmetric battery Li / Li assembled with the sulfide solid electrolyte 10 GeP2S 12 Li and Li of Example 1 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 symmetric battery Li / Li assembled with the sulfide solid electrolyte 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 Li, Li / Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 After the Li / Li symmetric battery of Example 1 was stably cycled for 750 hours, the polarization voltage slowly increased to ±0.3V, compared with the Li / Li 10 GeP2S 12 Li symmetric battery was severely polarized, and the polarization voltage increased to ±2.5V after about 230 hours. It proved that the Li 9.88 GeP 1.96 Sb 0.04 S 11.88 Cl 0.12 The interface stability of the sulfide solid electrolyte was significantly improved. In addition, in other examples, the lithium symmetric battery assembled with the corresponding sulfide solid electrolyte was more stable than the Li 10 GeP2S 12 The lithium symmetric battery assembled was also better in stability, and when stably cycled against lithium, the cycle life was increased by 3-17 times in the current density range of 0.1-5 mA cm -2 -2.

[0126] The above-described examples have been described in detail to illustrate the technical solutions of the present application. It should be understood that the above-described examples are only specific embodiments of the present application and are not intended to limit the present application. Any modification, supplement or similar replacement within the principle range of the present application should be included in the protection scope of the present application.

Claims

1. A method of using a sulfide solid electrolyte that is stable to solvents and lithium, characterized in that, The general chemical formula is Li 10-x GeP 2-q Sb q S 12-w R w Where 0 < x < 0.3, 0 < q < 0.2, 0 < w < 0.6, and R is selected from one or more of O, F, Cl, Br, and I; (1) According to the general formula Li 10-x GeP 2-q Sb q S 12-w R w Lithium source, germanium source, phosphorus source and antimony source in stoichiometric ratio are weighed and mechanically mixed to obtain precursor powder; (2) The precursor powder was calcined and naturally cooled to room temperature to obtain the sulfide solid electrolyte that is stable to solvent and lithium. The lithium source is Li2S, the germanium source is GeS2, the phosphorus source is P2S5, and the antimony source is SbR3 or Sb2R3. The sulfide solid electrolyte described above, which is stable to solvents and lithium, has SbS4. 3- Groups and PS4 3- Group; The sulfide solid electrolyte, which is stable to both solvent and lithium, is mixed with the solvent in a sealed container for 40 minutes. The ionic conductivity of the dried sulfide solid electrolyte remains above 80%, and it is used to prepare an all-solid-state battery. The solvent is at least one of toluene, chlorobenzene, xylene, p-xylene, dimethyl carbonate, N-methylformamide, dimethylacetamide, N,N-dimethylbutylamine, n-hexane, glycol dimethyl ether, dibutyl ether, ethanol, 1,2-ethylenediamine, dichloroethane, dibromomethane, anisole, triethyl phosphate, dimethyl sulfoxide, dichloromethane, 1,2-ethylenedithiol, acetonitrile, tetrahydrofuran, isopentyl ether, isopropyl ether, ethyl acetate, butyl butyrate, isopropyl ether, n-heptane, hexene, or ethyl acetate.

2. The method of using the sulfide solid electrolyte stable to solvents and lithium according to claim 1, characterized in that, The mechanical mixing is carried out under a vacuum or argon atmosphere.

3. The method of using the sulfide solid electrolyte stable to solvents and lithium according to claim 1, characterized in that, In step (1), the mechanical mixing method is mechanical stirring, mechanical vibration, ultrasonic dispersion, mechanical ball milling, high-energy ball milling or roller milling, and the mixing time is 1 to 48 hours.

4. The method of using the sulfide solid electrolyte stable to solvents and lithium according to claim 1, characterized in that, In step (2), the calcination conditions are: inert atmosphere, 500~700 °C, 0.5~24 hours.

5. The method of using the sulfide solid electrolyte stable to solvents and lithium according to claim 1, characterized in that, In step (2), the powder that has been calcined and naturally cooled to room temperature is pulverized and ground to obtain the sulfide solid electrolyte that is stable to solvents and lithium.

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