Glass ceramic sulfide electrolyte and preparation method thereof

Abstract

The embodiment of the invention provides a glass ceramic sulfide electrolyte and a preparation method thereof, and relates to the technical field of batteries. The method comprises the steps that Li2S, P2S5, MeOa and LiI are mixed in an inert gas environment to obtain precursor powder, Me represents a metal element, a represents the number of oxygen atoms in MeOa, and the value range of a is larger than or equal to 1 and smaller than or equal to 3. The preparation method comprises the following steps: preparing precursor powder, then carrying out non-crystallization treatment on the precursor powder to obtain a solid electrolyte powder precursor, and finally sintering the solid electrolyte powder precursor in an inert gas environment to obtain the glass ceramic sulfide electrolyte. The glass ceramic sulfide electrolyte prepared by the method has excellent interface stability and air stability and low Young modulus, in addition, the glass ceramic sulfide electrolyte also has excellent ionic conductivity, can meet the charge-discharge efficiency and power density of an all-solid-state battery, and further improves the battery performance.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to a glass-ceramic sulfide electrolyte and a preparation method thereof. Background Art

[0002] Under the background of the global acceleration towards the transformation to clean energy, extremely high requirements are imposed on battery performance in fields such as new energy vehicles and renewable energy energy storage systems. As a new type of electrolyte material, glass-ceramic sulfide electrolyte has a high ionic conductivity, and can also significantly improve the safety of batteries, meeting the requirements of rapid charging of electric vehicles and efficient charge and discharge of energy storage systems.

[0003] In the existing preparation technologies of glass-ceramic sulfide electrolytes, element doping technology is usually used to increase the ionic conductivity while maintaining the stability of the chemical interface. However, most of the existing doping technologies are single element doping. The glass-ceramic sulfide electrolytes prepared have a high Young's modulus, poor interface stability and air stability during the cycling process of all-solid-state batteries. More importantly, their ionic conductivity is not sufficient to meet the charge and discharge efficiency and power density of all-solid-state batteries.

[0004] Therefore, it is an urgent technical problem to provide a glass-ceramic sulfide electrolyte that simultaneously meets low Young's modulus, excellent interface stability and air stability, and further improves ionic conductivity. Summary of the Invention

[0005] The embodiments of this application provide a glass-ceramic sulfide electrolyte and a preparation method thereof, enabling the glass-ceramic sulfide electrolyte to have a low Young's modulus, excellent interface stability and air stability, and high ionic conductivity.

[0006] In a first aspect, the embodiments of this application provide a glass-ceramic sulfide electrolyte, and the molecular formula of the glass-ceramic sulfide electrolyte is Li7P 3-x Me x S 11-2.5x-0.5y O ax I y ;

[0007] where Me represents a metal element, the value range of a is 1≤a≤3, the value range of x is 0<x<0.5, and the value range of y is 0<y<1.

[0008] In a possible implementation manner, the value range of x is 0.05≦x≦0.3, and the value range of y is 0.1≦y≦0.5.

[0009] In a possible implementation manner, the Me includes any one of the following elements:

[0010] W, Mn, Ca or Ba.

[0011] In a second aspect, an embodiment of the present application provides a method for preparing a glass-ceramic sulfide electrolyte, the method comprising:

[0012] Mixing Li2S, P2S5, MeO a , and LiI in an inert gas environment to obtain a precursor powder, where Me represents a metal element and a represents the number of oxygen atoms in MeO a , and the value range of a is 1 ≤ a ≤ 3;

[0013] Performing an amorphization treatment on the precursor powder to obtain a precursor of a solid electrolyte powder;

[0014] Sintering the precursor of the solid electrolyte powder in an inert gas environment to obtain a glass-ceramic sulfide electrolyte.

[0015] In a possible implementation manner, the MeO a includes any one of the following:

[0016] WO3, MnO2, CaO or BaO.

[0017] In a possible implementation manner, before mixing Li2S, P2S5, MeO a , and LiI in an inert gas environment, the method further comprises:

[0018] Weighing Li2S, P2S5, MeO a , and LiI according to the molar ratio of (7 - y):(3 - x):2x:2y to obtain Li2S, P2S5, MeO a , and LiI.

[0019] In a possible implementation manner, the value range of x is 0 < x < 0.5, and the value range of y is 0 < y < 1.

[0020] In a possible implementation manner, the value range of x is 0.05 ≤ x ≤ 0.3, and the value range of y is 0.1 ≤ y ≤ 0.5.

[0021] In a possible implementation manner, the performing an amorphization treatment on the precursor powder to obtain a precursor of a solid electrolyte powder includes:

[0022] Placing the precursor powder in a ball milling jar and performing ball milling treatment using a ball mill to obtain the precursor of the solid electrolyte powder.

[0023] In a possible embodiment, during the ball milling treatment, the ball milling time is 3 hours to 50 hours, and / or the ball milling speed is 100 rpm to 800 rpm.

[0024] In a possible implementation manner, during sintering, the sintering time is 1 hour to 20 hours, and / or the sintering temperature is 200° C. to 400° C.

[0025] In a third aspect, an embodiment of the present application provides an all-solid-state battery, comprising: any possible glass-ceramic sulfide electrolyte described in the first aspect, and / or a glass-ceramic sulfide electrolyte prepared according to the second aspect and / or various possible implementations of the second aspect.

[0026] The present invention provides a glass ceramic sulfide electrolyte and a preparation method thereof, wherein Li2S, P2S5, MeO a , LiI are mixed under an inert gas environment to obtain a precursor powder, wherein Me represents a metal element, a represents MeO a The number of oxygen atoms in the electrolyte is determined by the reaction mixture, and the value of a is in the range of 1≤a≤3. The precursor powder is then amorphized to obtain a solid electrolyte powder precursor, and finally the solid electrolyte powder precursor is sintered in an inert gas environment to obtain a glass-ceramic sulfide electrolyte. The glass-ceramic sulfide electrolyte prepared by the above method has excellent interfacial stability and air stability as well as a low Young's modulus. In addition, the glass-ceramic sulfide electrolyte also has excellent ionic conductivity, which can meet the charge and discharge efficiency and power density of all-solid-state batteries, further improving battery performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0028] Figure 1 A schematic flow chart of a method for preparing a glass-ceramic sulfide electrolyte provided in this application.

[0029] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0030] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0031] First, the application background of this application is explained as follows:

[0032] Against the backdrop of an accelerating global transition to clean energy, new energy vehicles and renewable energy storage systems are booming, placing extremely high demands on battery performance. Traditional liquid electrolyte batteries pose safety risks such as flammability and explosion, and their energy density cannot meet the growing demand for long-range and large-capacity energy storage. This significantly limits the widespread adoption of electric vehicles and the stable operation of large-scale energy storage systems.

[0033] As a new type of electrolyte material, glass-ceramic sulfide electrolyte has high ionic conductivity, which can enable rapid migration of ions within the battery, thereby improving the battery's charge and discharge efficiency and power density, and meeting the needs of fast charging of electric vehicles and efficient charging and discharging of energy storage systems; its good mechanical properties and thermal stability can not only effectively inhibit the growth of lithium dendrites and avoid internal short circuits in the battery, but also adapt to a wider temperature range, ensuring the safe and stable operation of the battery in different environments; and the glass-ceramic sulfide electrolyte can achieve good interface contact with the electrode material, reduce the interface resistance, and further improve the overall performance of the battery.

[0034] In the existing preparation technology of glass-ceramic sulfide electrolytes, in order to improve ionic conductivity while ensuring the stability of the chemical interface, element doping technology has become a common means. However, the existing doping technology is mostly single-element doping, which is limited to the introduction of a single element. The prepared glass-ceramic sulfide electrolytes have exposed many problems during the actual circulation of all-solid-state batteries: on the one hand, the Young's modulus is relatively high, resulting in uneven stress distribution inside the battery; on the other hand, the interface stability between the electrolyte and the electrode is poor, and it is easy to have problems such as increased interface impedance during the cycle. In addition, the air stability of the electrolyte is also poor. More importantly, the ionic conductivity of the glass-ceramic sulfide electrolyte prepared by the single-element doping technology has never reached the ideal level, and cannot meet the actual requirements of all-solid-state batteries for charge and discharge efficiency and power density, which restricts the further improvement of the overall performance of the battery.

[0035] In summary, providing a glass-ceramic sulfide electrolyte that simultaneously meets the requirements of low Young's modulus, excellent interface stability and air stability, and further improves ionic conductivity is a technical problem that needs to be solved urgently.

[0036] Based on the above technical problems, the inventors found that the glass ceramic sulfide electrolyte - Li7P3S 11 The glass-ceramic sulfide electrolyte prepared by doping metal elements, oxygen elements and iodine elements has excellent interface stability (interface stability to lithium metal negative electrode) and air stability as well as low Young's modulus, maintaining good contact between the solid-solid interface between the positive and negative active materials and the glass-ceramic sulfide electrolyte, and can meet the requirements of low cycle pressure and low preparation pressure of all-solid-state batteries. More importantly, the glass-ceramic sulfide electrolyte prepared by the above method has excellent ionic conductivity, which can meet the charge and discharge efficiency and power density of all-solid-state batteries, further improving battery performance. Based on this, the present application provides a glass-ceramic sulfide electrolyte and a preparation method thereof.

[0037] The following specific embodiments describe in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0038] Figure 1 A schematic diagram of a process for preparing a glass-ceramic sulfide electrolyte provided in this application is shown in FIG. Figure 1 As shown, the method includes:

[0039] S101: Li2S, P2S5, MeO a , LiI are mixed under an inert gas environment to obtain a precursor powder, wherein Me represents a metal element, a represents MeO a The number of oxygen atoms in the molecule, a, ranges from 1≤a≤3.

[0040] In this step, lithium sulfide Li2S is an inorganic compound composed of lithium and sulfur, which serves as the lithium source and sulfur source in the glass-ceramic sulfide electrolyte; phosphorus pentasulfide P2S5 is an inorganic compound composed of phosphorus and sulfur, which is the most commonly used network forming body raw material in glass-ceramic sulfide electrolyte, and reacts with Li2S to form a skeleton that provides ion transmission channels; metal oxide MeO a It refers to a compound composed of metal elements and oxygen elements, which can be used as a doping substance to optimize the performance of glass-ceramic sulfide electrolytes, where Me represents a metal element and a represents MeOa The number of oxygen atoms in the electrolyte, a, ranges from 1≤a≤3. Specifically, the value of a is determined by the valence of the metal element Me. For example, when Me is W (W has a valence of +6), the value of a is 3, when Me is Mn (Mn has a valence of +4), the value of a is 2, and when Me is Ca (Ca has a valence of +2), the value of a is 1. Lithium iodide LiI is an inorganic compound composed of lithium and iodine. It can be used as a modifier. Due to the large radius of iodine ions, it can expand the transmission channel of lithium ions, promote lithium ion migration, and improve ionic conductivity. Inert gas refers to a gas with very inactive chemical properties, which can be argon, neon, helium, nitrogen, etc.

[0041] Specifically, since sulfides such as Li2S and P2S5 can easily react with water and oxygen in the air, for example, when Li2S meets water, it will generate harmful gas hydrogen sulfide H2S and unnecessary by-product lithium hydroxide LiOH, and when P2S5 meets water, it will generate harmful gas H2S and unnecessary by-product phosphoric acid H3PO4. Therefore, in order to ensure that the glass ceramic sulfides are not contaminated or deteriorated during the preparation process, Li2S, P2S5, MeO a , LiI are mixed in an inert gas environment so that these raw materials with different physical forms and densities are evenly dispersed together to form a precursor powder with relatively uniform chemical composition distribution, providing a material basis for the preparation of glass-ceramic sulfide electrolytes.

[0042] S102: performing amorphization treatment on the precursor powder to obtain a solid electrolyte powder precursor.

[0043] In this step, the amorphization treatment aims to disrupt the crystal structure of the precursor powder, transforming it from an ordered crystalline or partially crystalline state to a disordered amorphous state (glassy state). The amorphous structure reduces the obstacles encountered by ions moving through the electrolyte, allowing them to move more freely, thereby improving ionic conductivity. Secondly, the amorphous structure lacks the distinct grain boundaries of the crystalline structure (grain boundaries are often weak links in ion transport and easily generate impedance), which helps reduce the obstructive effect of grain boundaries and further improves ionic conductivity. Thirdly, the atomic arrangement of the amorphous structure has a certain degree of flexibility, which can better adapt to volume changes in response to external environmental changes or contact with electrode materials, enhancing the compatibility and stability between the electrolyte and the motor. Common amorphization treatment methods include mechanical ball milling and melt quenching. The resulting solid electrolyte powder precursor is a transitional form of the target electrolyte (glass-ceramic sulfide electrolyte).

[0044] Optionally, in the amorphization treatment of the precursor powder by mechanical ball milling, the precursor powder is placed in a ball mill, and the high-speed rotation and collision of the grinding balls cause the precursor powder particles to be subjected to strong mechanical forces, thereby destroying the crystal structure and obtaining an amorphous solid electrolyte powder precursor.

[0045] Optionally, in the amorphization treatment of the precursor powder by the melt quenching method, the precursor powder is first heated to a molten state to completely disintegrate the original crystal structure, and then rapidly cooled so that the atoms do not have time to rearrange to form crystals, thereby obtaining an amorphous solid electrolyte powder precursor.

[0046] The amorphous solid electrolyte powder precursor obtained by amorphization treatment has a more uniform composition distribution and a structure that is more conducive to ion conduction, providing a basis for the subsequent preparation of glass-ceramic sulfide electrolytes with excellent interface stability, low Young's modulus and high ionic conductivity.

[0047] S103: Sintering the solid electrolyte powder precursor in an inert gas environment to obtain a glass ceramic sulfide electrolyte.

[0048] In this step, sintering refers to applying a temperature corresponding to the melting point of the solid electrolyte powder precursor, using thermal energy to drive material migration between the powder particles of the solid electrolyte powder precursor, thereby expanding the contact points between the particles, gradually reducing or closing the gaps, and ultimately transforming the loose solid electrolyte powder precursor into a dense solid.

[0049] Similarly, the entire sintering process needs to be in an inert gas environment to prevent sulfides and other components in the solid electrolyte powder precursor powder from reacting with water or oxygen in the air to produce harmful gases or by-products. The inert gas can be argon, neon, helium, nitrogen, etc.

[0050] For example, a sufficient amount of argon is introduced into a sealed sintering furnace or reaction vessel to completely expel the air. The solid electrolyte powder precursor is then placed in a mold or crucible, placed in a sintering device, and sintered at a preset temperature. During the sintering process, as the temperature rises, the amorphous structure in the solid electrolyte powder precursor powder partially crystallizes to form a regularly arranged crystalline structure while retaining a certain amount of amorphous structure, ultimately resulting in a glass-ceramic sulfide electrolyte with a glass phase (amorphous) and a ceramic phase (crystalline) structure.

[0051] The preparation method of the glass ceramic sulfide electrolyte provided in the embodiment of the present application is as follows: Li2S, P2S5, MeO a, LiI is mixed in an inert gas environment to obtain a precursor powder, and then the precursor powder is subjected to amorphization treatment to obtain a solid electrolyte powder precursor. Finally, the solid electrolyte powder precursor is sintered in an inert gas environment to obtain a glass-ceramic sulfide electrolyte. By the above method, the prepared glass-ceramic sulfide electrolyte has excellent interfacial stability, air stability and low Young's modulus. More importantly, the glass-ceramic sulfide electrolyte has excellent ionic conductivity, can meet the charge-discharge efficiency and power density of all-solid-state batteries, and further improves the battery performance.

[0052] Based on Figure 1 In Example, in S101: Before mixing Li2S, P2S5, MeO a , LiI in an inert gas environment, the preparation method of the glass-ceramic sulfide electrolyte further includes:

[0053] Weigh Li2S, P2S5, MeO a , LiI according to the molar ratio of (7 - y):(3 - x):2x:2y. Wherein, the value range of x is 0 < x < 0.5, and the value range of y is 0 < y < 1.

[0054] In a possible implementation manner, MeO a includes any one of the following: WO3, MnO2, CaO or BaO.

[0055] Taking manganese dioxide MnO2 as an example, MnO2 is a common metal oxide, usually presented as black or brownish-black powder. MnO2 has strong oxidizing property and can react with various reducing agents. In addition, MnO2 is relatively stable under alkaline conditions and is not easily dissolved. Due to its oxidizing property and stability, MnO2 is widely used in the preparation of battery materials, catalysts and glass-ceramic materials. Especially in batteries, it is commonly used as the positive electrode material of lithium-ion batteries and alkaline batteries, which can effectively promote charge transfer and improve the capacity and cycle life of the battery.

[0056] x and y are two adjustable variables, and their values directly affect the specific molar proportion of each raw material of the glass-ceramic sulfide electrolyte. Among them, x mainly controls the doping amount of metal elements, and y mainly controls the doping amount of iodine elements. x can take values such as 0.01, 0.1, 0.2, 0.3, 0.4 or 0.48, etc., and y can take values such as 0.01, 0.1, 0.2, 0.5, 0.8 or 0.9, etc. x and y act together on the ratio of each raw material, providing a flexible adjustment space for optimizing the performance of the glass-ceramic sulfide electrolyte by regulating the composition. In addition, Li2S, P2S5, MeO <F000025>​​, the molar ratio of LiI (7 - y):(3 - x):2x:2y also indicates that the prepared glass - ceramic sulfide electrolyte is based on the Li7P3S 11 system.

[0057] Exemplarily, weigh Li2S, P2S5, MnO2, and LiI according to the molar ratio of Li2S:P2S5:MnO2:LiI being 6.99:2.99:0.02:0.02, or weigh Li2S, P2S5, WO3, and LiI according to the molar ratio of Li^2S:P2S5:WO3:LiI being 6.1:2.52:0.96:1.8, or weigh Li2S, P2S5, CaO, and LiI according to the molar ratio of Li2S:P2S5:CaO:LiI being 6.5:2.7:0.6:1, or weigh Li2S, P2S5, WO3, and LiI according to the molar ratio of Li2S:P2S5:WO3:LiI being 6.1:2.99:0.02:1.8, or weigh Li2S, P2S5, BaO, and LiI according to the molar ratio of Li2S:P2S5:BaO:LiI being 6.98:2.51:0.98:0.04. It can be understood that in addition to the above - mentioned specific molar ratios, according to different selections of x and y within their respective value ranges, other raw material ratios that meet the conditions of 0 < x < 0.5 and 0 < y < 1, such as the molar ratio of Li2S:P2S5:MeO a , LiI being 6.9:2.9:0.2:0.2, 6.3:2.7:0.6:1.4, etc., can be obtained to meet different performance optimization requirements.

[0058] Furthermore, preferably, the value range of x is 0.05 ≤ x ≤ 0.3, and the value range of y is 0.1 ≤ y ≤ 0.5.

[0059] x may be 0.05, 0.1, 0.2 or 0.3, and y may be 0.1, 0.2, 0.3, 0.4 or 0.5. For example, Li2S, P2S5, MnO2, and LiI are weighed in a molar ratio of 6.9:2.95:0.1:0.2 to obtain Li2S, P2S5, MnO2, and LiI, or Li2S, P2S5, BaO, and LiI are weighed in a molar ratio of 6.5:2.7:0.6:1 to obtain Li2S, P2S5, BaO, and LiI, or Li2S, P2S5, WO3, and LiI are weighed in a molar ratio of 6.7:2.95:0.1:0.2 to obtain Li2S, P2S5, BaO, and LiI, or Li2S, P2S5, WO3, and LiI are weighed in a molar ratio of 6.7:2.95:0.1:0.2 to obtain Li2S, P2S5, BaO, and LiI, :2.8:0.4:0.6 weighed to obtain Li2S, P2S5, WO3, LiI, or, according to the molar ratio of Li2S, P2S5, CaO, LiI of 6.5:2.95:0.1:1 weighed to obtain Li2S, P2S5, CaO, LiI, or, according to the molar ratio of Li2S, P2S5, WO3, LiI of 6.9:2.7:0.6:0.2 weighed to obtain Li2S, P2S5, WO3, LiI. It is understandable that in addition to the above specific molar ratios, according to different selections of x and y within their respective value ranges, other molar ratios such as Li2S, P2S5, MeO a The molar ratio of LiI is 6.8:2.9:0.2:0.4, 6.6:2.75:0.5:0.8 and other raw material ratios that meet the conditions of 0.05≦x≦0.3 and 0.1≦y≦0.5 to meet different preferred performance optimization requirements.

[0060] It should be noted that the specific values ​​of x and y, namely Li2S, P2S5, MeO a The molar ratio of Li2S, P2S5, MeO2 and LiI is only used as an example and should be adjusted appropriately according to actual needs in actual applications. a , LiI, provide the material basis for the subsequent preparation of glass-ceramic sulfide electrolytes, and can provide flexible adjustment space for optimizing the performance of glass-ceramic sulfide electrolytes by regulating x and y.

[0061] exist Figure 1 Based on the embodiment, in S102: performing amorphization treatment on the precursor powder to obtain a solid electrolyte powder precursor specifically includes:

[0062] The precursor powder is placed in a ball milling jar and ball milled using a ball mill to obtain a solid electrolyte powder precursor.

[0063] A ball mill is a container for holding precursor powder and grinding media (such as carbide balls, zirconia balls, etc.) during the ball milling process. It is usually made of wear-resistant materials (such as agate, stainless steel, etc.) and can withstand the impact and friction during grinding. A ball mill is a device that uses high-speed rotation, rotation or planetary motion of the ball mill body to cause the grinding media to impact and grind the precursor powder, thereby achieving the refinement of the precursor powder.

[0064] As described in S102, commonly used amorphization treatment methods include mechanical ball milling, melt quenching, etc. In a specific implementation of this solution, the precursor powder is amorphized by mechanical ball milling, that is, the precursor powder is placed in a ball milling tank, and the ball milling speed and ball milling time of the ball mill are controlled to make the precursor powder drive the grinding media in the tank to produce violent impact, friction and shearing, so that the precursor powder is transformed from an ordered crystalline state or a partially crystalline state to a disordered amorphous state, thereby obtaining a solid electrolyte powder precursor.

[0065] In a possible embodiment, during the ball milling treatment, the ball milling time is 3 hours to 50 hours, and / or the ball milling speed is 100 rpm to 800 rpm.

[0066] Ball milling time refers to the duration of ball milling of precursor powder, and is one of the key parameters for controlling the ball milling effect. Ball milling speed refers to the rotation speed of the ball mill during operation (unit: rpm, revolutions per minute), that is, the number of revolutions of the ball mill per minute, which directly affects the intensity of the grinding medium on the precursor powder.

[0067] Optionally, the ball milling time can be 3 hours, 10 hours, 20 hours, 30 hours, 40 hours, or 50 hours, and the ball milling speed can be 100 rpm, 300 rpm, 500 rpm, 600 rpm, or 800 rpm. For precursor powders with high hardness and difficulty in refining, a longer ball milling time (e.g., 30 to 50 hours) and / or a higher ball milling speed (e.g., 500 to 800 rpm) can be selected to effectively refine the particles by enhancing the impact and friction of the grinding media on the precursor powder. For precursor powders that are easier to handle, a shorter ball milling time (e.g., 3 to 10 hours) and / or a lower ball milling speed (e.g., 100 to 300 rpm) can be selected to achieve the desired mixing and refining effect.

[0068] exist Figure 1 Based on the embodiment, in S103: sintering the solid electrolyte powder precursor in an inert gas environment to obtain a glass ceramic sulfide electrolyte specifically includes:

[0069] In a possible implementation, during sintering, the sintering time is 1 h to 20 h, and / or the sintering temperature is 200 °C to 400 °C.

[0070] The sintering time refers to the duration for which the solid electrolyte powder precursor is maintained at the preset sintering temperature, which determines the degree of densification of the solid electrolyte powder precursor. The sintering temperature refers to the preset heating temperature during the sintering process, which determines the energy level of the migration (diffusion, flow) of the solid electrolyte powder precursor and the microstructure (such as glass refraction, crystallization).

[0071] Optionally, the sintering time can be 1 h, 5 h, 10 h, 13 h, 15 h, 17 h or 20 h, etc., and the sintering temperature can be 200 °C, 250 °C, 300 °C, 350 °C or 400 °C, etc. In practical applications, usually a combination of a shorter sintering time and a higher sintering temperature or a longer sintering time and a lower sintering temperature is used to balance the relationship between rapid densification and material stability.

[0072] The specific values of the above-mentioned ball milling time, ball milling speed, sintering temperature and sintering time are only for illustration, and this application does not make specific limitations.

[0073] This application provides a glass-ceramic sulfide electrolyte. The molecular formula of the glass-ceramic sulfide electrolyte is Li7P 3-x Me x S 11-2.5x-0.5y O ax I y ; where Me represents a metal element, the value range of a is 1 ≤ a ≤ 3, the value range of x is 0 < x < 0.5, and the value range of y is 0 < y < 1.

[0074] Through Figure 1 the method described in the examples, the prepared glass-ceramic sulfide electrolyte has the molecular formula Li7P 3- x Me x S 11-2.5x-0.5y O ax I<​​​​The number of oxygen atoms, and the value of a is determined by the valence of the metal element Me. Exemplarily, when Me is W (the valence of W is +6), the value of a is 3; when Me is Mn (the valence of Mn is +4), the value of a is 2; when Me is Ca or Ba (the valence of Ca is +2, and the valence of Ba is +2), the value of a is 1. x can take values of 0.01, 0.1, 0.2, 0.3, 0.4, or 0.48, and y can take values of 0.01, 0.1, 0.2, 0.5, 0.8, or 0.9, etc., other values that satisfy 0 < x < 0.5 and 0 < y < 1.

[0075] In a possible implementation, Me includes any one of the following elements: W, Mn, Ca, or Ba.

[0076] Exemplarily, through Figure 1 the method described in the examples, the molecular formula of the glass-ceramic sulfide electrolyte prepared can be Li7P 2.99 Ba 0.01 S 10.97 O 0.01 I 0.01 、Li7P 2.52 Ca 0.48 S 9.35 O 0.48 I 0.9 、Li7P 2.99 W 0.01 S 10.525 O 0.03 I 0.9 、Li7P 2.51 W 0.49 S 9.765 O 1.47 I 0.02 、Li7P 2.7 Mn 0.3 S 10 O 0.6 I 0.5 or Li7P 2.6 W 0.4 S 9.65 O 1.2 I 0.7 etc.

[0077] Furthermore, preferably, the value range of x is 0.05 ≤ x ≤ 0.3, and the value range of y is 0.1 ≤ y ≤ 0.5.

[0078] As described in the above examples, x can take values of 0.05, 0.1, 0.2, or 0.3, and y can take values of 0.1, 0.2, 0.3, 0.4, or 0.5, etc., other values that satisfy 0.05 ≤ x ≤ 0.3 and 0.1 ≤ y ≤ 0.5. Exemplarily, through Figure 1The molecular formula of the glass-ceramic sulfide electrolyte prepared by the method described in the embodiment can be Li7P 2.8 Mn 0.2 S 10.35 O 0.4 I 0.3 、Li7P 2.95 Ca 0.05 S 10.825 O 0.05 I 0.1 、Li7P 2.7 W 0.3 S 10 O 0.9 I 0.5 、Li7P 2.95 Ba 0.05 S 10.625 O 0.05 I 0.5 or Li7P 2.7 Mn 0.3 S 10.2 O 0.6 I 0.1 wait.

[0079] pass Figure 1 The glass-ceramic sulfide electrolyte prepared by the method described in the examples has excellent interface stability (interface stability to the lithium metal negative electrode), air stability and low Young's modulus. More importantly, the glass-ceramic sulfide electrolyte has excellent ionic conductivity, which can meet the charge and discharge efficiency and power density of all-solid-state batteries, further improving battery performance.

[0080] The present application also provides an all-solid-state battery, comprising: the glass-ceramic sulfide electrolyte prepared by the method described in the above embodiment, and / or the glass-ceramic sulfide electrolyte described in the above embodiment.

[0081] The glass-ceramic sulfide electrolyte and its preparation method provided in this application will be specifically introduced through specific examples below.

[0082] Unless otherwise specified, the reagents, materials, and instruments used in the following examples are conventional reagents, conventional materials, and conventional instruments in the art and can be obtained commercially. The reagents involved can also be synthesized by conventional methods in the art.

[0083] Example 1

[0084] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.95 Mn 0.05 S 10.825 O 0.1 I 0.1, and its preparation method comprises the following steps:

[0085] (1) Li2S, P2S5, MnO2, and LiI were weighed according to a molar ratio of Li2S, P2S5, MnO2, and LiI of 6.9:2.95:0.1:0.2, placed in a mortar in an argon-filled glove box, and manually mixed for 30 min to obtain a precursor powder.

[0086] (2) The precursor powder obtained in step (1) is placed in a ball mill jar and sealed, and amorphized by ball milling using a planetary ball mill (ball milling speed of 600 rpm, ball milling time of 24 h) to obtain a solid electrolyte powder precursor.

[0087] (3) The solid electrolyte powder precursor obtained in step (2) is placed in a muffle furnace filled with argon and sintered (the sintering temperature is 300 ° C and the sintering time is 5 h) to obtain a solid electrolyte with the molecular formula Li7P 2.95 Mn 0.05 S 10.825 O 0.1 I 0.1 Glass-ceramic sulfide electrolyte.

[0088] Example 2

[0089] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.95 Ca 0.05 S 10.625 O 0.05 I 0.5 The preparation method is basically the same as that described in Example 1, except that: in step (1): Li2S, P2S5, CaO, and LiI are weighed according to the molar ratio of Li2S, P2S5, CaO, and LiI of 6.5:2.95:0.1:1, and placed in a mortar in an argon-filled glove box and manually mixed for 30 minutes to obtain a precursor powder. The final product is Li7P 2.95 Ca 0.05 S 10.625 O 0.05 I 0.5 Glass-ceramic sulfide electrolyte.

[0090] Example 3

[0091] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.9 Mn 0.1 S 10.7 O 0.2 I 0.1The preparation method is basically the same as that described in Example 1, except that:

[0092] (1) Li2S, P2S5, MnO2, and LiI were weighed according to a molar ratio of Li2S, P2S5, MnO2, and LiI of 6.9:2.9:0.2:0.2, placed in a mortar in an argon-filled glove box, and manually mixed for 30 min to obtain a precursor powder.

[0093] (2) The precursor powder obtained in step (1) was placed in a ball mill jar and sealed, and amorphized by ball milling using a planetary ball mill (ball milling speed of 500 rpm, ball milling time of 36 h) to obtain a solid electrolyte powder precursor.

[0094] (3) The same as step (3) in Example 1.

[0095] The final molecular formula is Li7P 2.9 Mn 0.1 S 10.7 O 0.2 I 0.1 Glass-ceramic sulfide electrolyte.

[0096] Example 4

[0097] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.8 Mn 0.2 S 10.35 O 0.4 I 0.3 The preparation method is basically the same as that described in Example 1, except that: in step (1): Li2S, P2S5, MnO2, and LiI are weighed according to the molar ratio of Li2S, P2S5, MnO2, and LiI of 6.7:2.8:0.4:0.6, and placed in a mortar in a glove box filled with argon and manually mixed for 30 minutes to obtain a precursor powder. The final product is Li7P 2.8 Mn 0.2 S 10.35 O 0.4 I 0.3 Glass-ceramic sulfide electrolyte.

[0098] Example 5

[0099] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.7 Mn 0.3 S 10.2 O 0.6 I 0.1The preparation method is basically the same as that described in Example 1, except that:

[0100] (1) Li2S, P2S5, MnO2, and LiI were weighed according to the molar ratio of Li2S, P2S5, MnO2, and LiI of 6.9:2.7:0.6:0.2, placed in a mortar in an argon-filled glove box, and manually mixed for 30 min to obtain a precursor powder.

[0101] (2) The same as step (2) in Example 1.

[0102] (3) The solid electrolyte powder precursor obtained in step (2) was placed in a muffle furnace filled with argon and sintered (the sintering temperature was 260 ° C and the sintering time was 10 h) to obtain a solid electrolyte with the molecular formula Li7P 2.7 Mn 0.3 S 10.2 O 0.6 I 0.1 Glass-ceramic sulfide electrolyte.

[0103] Example 6

[0104] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.7 Ba 0.3 S 10 O 0.3 I 0.5 The preparation method is basically the same as that described in Example 1, except that: in step (1): Li2S, P2S5, BaO, and LiI are weighed according to the molar ratio of Li2S, P2S5, BaO, and LiI of 6.5:2.7:0.6:1, and placed in a mortar in an argon-filled glove box and manually mixed for 30 minutes to obtain a precursor powder. The final product is Li7P 2.7 Ba 0.3 S 10 O 0.3 I 0.5 Glass-ceramic sulfide electrolyte.

[0105] Example 7

[0106] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.99 W 0.01 S 10.97 O 0.03 I 0.01 The preparation method is basically the same as that described in Example 1, except that:

[0107] (1) Li2S, P2S5, WO3, and LiI were weighed according to a molar ratio of Li2S, P2S5, WO3, and LiI of 6.99:2.99:0.02:0.02, placed in a mortar in an argon-filled glove box, and manually mixed for 30 min to obtain a precursor powder.

[0108] (2) The precursor powder obtained in step (1) is placed in a ball mill jar and sealed, and amorphized by ball milling using a planetary ball mill (ball milling speed of 700 rpm, ball milling time of 24 h) to obtain a solid electrolyte powder precursor.

[0109] (3) The solid electrolyte powder precursor obtained in step (2) was placed in a muffle furnace filled with argon and sintered (the sintering temperature was 320 ° C and the sintering time was 5 h) to obtain a solid electrolyte with the molecular formula Li7P 2.99 W 0.01 S 10.97 O 0.03 I 0.01 Glass-ceramic sulfide electrolyte.

[0110] Example 8

[0111] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.52 W 0.48 S 9.35 O 1.44 I 0.9 The preparation method is basically the same as that described in Example 7, except that: in step (1): Li2S, P2S5, WO3, and LiI are weighed according to the molar ratio of Li2S, P2S5, WO3, and LiI of 6.1:2.52:0.96:1.8, and placed in a mortar in an argon-filled glove box and manually mixed for 30 minutes to obtain a precursor powder. The final product is Li7P 2.52 W 0.48 S 9.35 O 1.44 I 0.9 Glass-ceramic sulfide electrolyte.

[0112] Example 9

[0113] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.99 Ca 0.01 S 10.525 O 0.01 I 0.9The preparation method is basically the same as that described in Example 7, except that: in step (1): Li2S, P2S5, WO3, and LiI are weighed according to the molar ratio of Li2S, P2S5, WO3, and LiI of 6.1:2.99:0.02:1.8, and placed in a mortar in an argon-filled glove box and manually mixed for 30 minutes to obtain a precursor powder. The final product is Li7P 2.99 Ca 0.01 S 10.525 O 0.01 I 0.9 Glass-ceramic sulfide electrolyte.

[0114] Example 10

[0115] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.51 W 0.49 S 9.765 O 1.47 I 0.02 The preparation method is basically the same as that described in Example 7, except that:

[0116] (1) Li2S, P2S5, WO3, and LiI were weighed according to a molar ratio of Li2S, P2S5, WO3, and LiI of 6.98:2.51:0.98:0.04, placed in a mortar in an argon-filled glove box, and manually mixed for 30 min to obtain a precursor powder.

[0117] (2) The precursor powder obtained in step (1) is placed in a ball mill jar and sealed, and amorphized by ball milling using a planetary ball mill (ball milling speed of 800 rpm, ball milling time of 15 h) to obtain a solid electrolyte powder precursor.

[0118] (3) The same as step (3) in Example 7.

[0119] The final molecular formula is Li7P 2.51 W 0.49 S 9.765 O 1.47 I 0.02 Glass-ceramic sulfide electrolyte.

[0120] Example 11

[0121] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.7 Ba 0.3 S 10.2 O 0.3 I 0.1The preparation method is basically the same as that described in Example 7, except that: in step (1): Li2S, P2S5, BaO, and LiI are weighed according to the molar ratio of Li2S, P2S5, BaO, and LiI of 6.9:2.7:0.6:0.2, and placed in a mortar in an argon-filled glove box and manually mixed for 30 minutes to obtain a precursor powder. The final product is Li7P 2.7 Ba 0.3 S 10.2 O 0.3 I 0.1 Glass-ceramic sulfide electrolyte.

[0122] Example 12

[0123] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P 2.7 W 0.3 S 10 O 0.9 I 0.5 The preparation method is basically the same as that described in Example 7, except that:

[0124] (1) Li2S, P2S5, WO3, and LiI were weighed according to a molar ratio of Li2S, P2S5, WO3, and LiI of 6.5:2.7:0.6:1, placed in a mortar in an argon-filled glove box, and manually mixed for 30 min to obtain a precursor powder.

[0125] (2) The same as step (2) in Example 7.

[0126] (3) The solid electrolyte powder precursor obtained in step (2) was placed in a muffle furnace filled with argon and sintered (the sintering temperature was 280 ° C and the sintering time was 8 h) to obtain a solid electrolyte with the molecular formula Li7P 2.7 W 0.3 S 10 O 0.9 I 0.5 Glass-ceramic sulfide electrolyte.

[0127] Comparative Example

[0128] This embodiment provides a glass ceramic sulfide electrolyte, the molecular formula of which is Li7P3S 11 The preparation method is basically the same as that described in Example 1, except that: in step (1): Li2S and P2S5 are weighed according to a molar ratio of Li2S to P2S5 of 7:3, and placed in a mortar in an argon-filled glove box and manually mixed for 30 minutes to obtain a precursor powder. The final product is Li7P3S11 Glass-ceramic sulfide electrolyte.

[0129] Test Example 1

[0130] Ionic conductivity test: 100 mg of each of the glass-ceramic sulfide electrolytes prepared in Examples 1 to 12 and the comparative example was weighed and placed in a mold. A pressure of 360 MPa was applied to press the electrolyte sheet. While pressure was applied, the impedance value of the glass-ceramic sulfide electrolyte was measured at room temperature (25°C) using an electrochemical workstation and electrochemical impedance spectroscopy. The real part value corresponding to the minimum absolute value of multiple impedance phase angles was taken as the effective impedance value. The ionic conductivity of the glass-ceramic sulfide electrolyte was calculated using this resistance value. The calculation formula is: ,in, represents the ionic conductivity (unit: mS / cm), L represents the thickness of the electrolyte sheet (unit: cm), R represents the effective impedance value of the glass-ceramic sulfide electrolyte obtained by electrochemical impedance spectroscopy (unit: Ω), and S represents the cross-sectional area of ​​the electrolyte sheet (unit: cm 2 ). The test results of ionic conductivity are shown in Table 1.

[0131] Test Example 2

[0132] Lithium metal stability test: 100 mg of the glass ceramic sulfide electrolyte prepared in Examples 1 to 12 and the comparative example were weighed and placed in a mold. A pressure of 360 MPa was applied to press the electrolyte sheet. Then, a 50 mm thick electrolyte was placed on both sides of the electrolyte sheet. The lithium sheets are combined into a lithium symmetric battery. The battery is recorded at 0.1mA / cm 2 Cycle time under constant current test conditions. The stability test results of all-solid-state batteries for lithium metal are shown in Table 2.

[0133] Test Example 3

[0134] Air Stability Test: After completing the ionic conductivity test for the glass-ceramic sulfide electrolytes prepared in Examples 1-12 and the comparative example, a 100 mg sample was taken and allowed to stand for 3 hours in an environment at a temperature of 25±3°C and a dew point of ≤-55°C. After this standstill, the ionic conductivity was retested, and the ionic conductivity retention ratio was calculated. The results of the air stability test are shown in Table 3.

[0135] Test Example 4

[0136] Battery cycle performance test: In an argon glove box, the glass ceramic sulfide electrolyte prepared in Examples 1 to 12 and the comparative example, the positive electrode active material Li (Ni 0.8 Co 0.1 Mn 0.1)O2(NCM811) was weighed at a weight ratio of 20:80. It was ground evenly using an agate mortar to prepare a composite positive electrode material. Then, in an insulating outer cylinder with a diameter of 10 mm, 14 mg of the above-mentioned composite positive electrode material and 70 mg of the glass ceramic sulfide electrolyte prepared in Examples 1 to 12 and Comparative Example 1 were stacked. It was press-formed at a pressure of 360 MPa to obtain a positive electrode and a solid electrolyte layer. Next, a piece of aluminum foil was stacked on the positive electrode side to form a current collector on the positive electrode side. Then, on the opposite side of the solid electrolyte layer that was in contact with the positive electrode, a film with a thickness and diameter of 200 mm was placed. and 10mm lithium sheet as negative electrode material. It was press-formed at a pressure of 80MPa to obtain a laminate consisting of a positive electrode, a solid electrolyte layer and a negative electrode. Then, stainless steel collectors were placed above and below the laminate, and current collector leads were attached to the collectors. The assembled solid-state battery was subjected to a cycle performance test under the following test conditions: current density of 1C, voltage range of 2.7V~4.3V (Li + The battery cycle performance test results are shown in Table 4.

[0137] Table 1 Test results of ionic conductivity

[0138]

[0139] According to Table 1, the following conclusions can be drawn:

[0140] Compared with the comparative example, it can be seen from Examples 1 to 12 that the ionic conductivity of the glass-ceramic sulfide electrolyte prepared by the element doping technology of metal elements, oxygen elements and iodine elements is between 2.46mS / cm and 4.93mS / cm, and the average ionic conductivity can reach 3.6mS / cm, which is much higher than that of the glass-ceramic sulfide electrolyte Li7P3S provided in the comparative example. 11 The ionic conductivity is 1.81 mS / cm. This is because metal and oxygen elements can change the crystal structure of the sulfide electrolyte, facilitating the migration of lithium ions and thus improving ionic conductivity. The glass-ceramic sulfide electrolyte and preparation method provided in this application have excellent ionic conductivity and can meet the charge and discharge efficiency and power density requirements of all-solid-state batteries.

[0141] Table 2 All-solid-state battery stability test results for lithium metal

[0142]

[0143] According to Table 2, the following conclusions can be drawn:

[0144] Compared with the comparative example, it can be seen from Examples 1 to 12 that the glass-ceramic sulfide electrolyte prepared by the element doping technology of metal elements, oxygen elements and iodine elements has a battery cycle time of 512h~924h when in contact with a lithium symmetrical battery, and the average cycle time can reach 739.58h, which is much higher than the glass-ceramic sulfide electrolyte Li7P3S provided in the comparative example. 11 The battery cycle time (378h) when in contact with a lithium symmetric battery shows that the glass-ceramic sulfide electrolytes provided by Examples 1 to 12 have good lithium metal stability, while the glass-ceramic sulfide electrolyte Li7P3S provided by the comparative example has good lithium metal stability. 11 When in contact with lithium metal, continuous side reactions are likely to occur, leading to the formation of an unstable solid electrolyte layer at the interface, and may even cause corrosion of the lithium metal, which in turn makes it impossible to maintain the cycle process for a long time.

[0145] The glass-ceramic sulfide electrolyte and preparation method thereof provided in the present application have excellent interface stability (interface stability to lithium metal negative electrode).

[0146] Table 3 Air stability test results

[0147]

[0148] According to Table 3, the following conclusions can be drawn:

[0149] Compared with the comparative example, it can be seen from Examples 1 to 12 that the glass-ceramic sulfide electrolyte prepared by the element doping technology of metal elements, oxygen elements and iodine elements has an ionic conductivity of 1.98mS / cm~4.25mS / cm after exposure, and the average ionic conductivity after exposure can reach 3.06mS / cm, and the retention rate is between 77.95% and 89.47%, and the average retention rate can reach 84.27%, which is much higher than the glass-ceramic sulfide electrolyte Li7P3S provided in the comparative example. 11 The ionic conductivity after exposure (0.79 mS / cm) and the retention rate (43.65%) show that the ionic conductivity of the glass-ceramic sulfide electrolytes provided in Examples 1 to 12 remains at a high level after exposure to air. The average ionic conductivity after exposure is only 0.54 mS / cm lower than the average ionic conductivity at the initial measurement. 11 The ionic conductivity after exposure was 1.02 mS / cm lower than the ionic conductivity at the time of initial measurement. In other words, the glass-ceramic sulfide electrolyte and preparation method thereof provided in this application provide a glass-ceramic sulfide electrolyte having excellent air stability.

[0150] Table 4 Battery cycle performance test results

[0151]

[0152] According to Table 4, the following conclusions can be drawn:

[0153] Compared with the comparative example, Examples 1 to 12 show that the glass-ceramic sulfide electrolyte is prepared by the element doping technology of metal elements, oxygen elements and iodine elements, and the first efficiency and 100-cycle capacity retention rates of the all-solid-state battery are between 81.50% and 88.10% and between 82.50% and 91.20%, respectively. The average first efficiency and average 100-cycle capacity retention rates can reach 83.92% and 87.01%, respectively, which are much higher than the glass-ceramic sulfide electrolyte Li7P3S provided in the comparative example. 11 The first efficiency (76.30%) and 100-cycle capacity retention rate (67.70%) of the all-solid-state battery obtained thereby are shown to be 76.30% and 67.70% respectively. This indicates that the all-solid-state batteries obtained by using the glass-ceramic sulfide electrolytes provided in Examples 1 to 12 maintain a high charge and discharge efficiency both in the first charge and after 100 charge and discharge cycles. The low Young's modulus of the electrolyte helps the all-solid-state battery maintain a stable contact between the electrolyte and the electrode material during the cycle, thereby reducing capacity attenuation. The glass-ceramic sulfide electrolyte Li7P3S provided in the comparative example 11 After 100 charge and discharge cycles, the ratio of discharge capacity to charging capacity of the obtained all-solid-state battery was only 67.70%, which means that the battery capacity has decayed to a certain extent.

[0154] The glass-ceramic sulfide electrolyte and its preparation method provided in the present application have the characteristics of low Young's modulus, which can maintain good solid-solid interface contact between the active material and the solid electrolyte to extend the cycle life of the solid-state battery and meet the requirements of low cycle pressure and low preparation pressure of the all-solid-state battery.

[0155] In summary, the glass-ceramic sulfide electrolyte and its preparation method provided in this application have excellent interfacial stability (interfacial stability to the lithium metal negative electrode and air stability) and low Young's modulus. More importantly, the glass-ceramic sulfide electrolyte has excellent ionic conductivity.

[0156] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A glass ceramic sulfide electrolyte, characterized in that: The molecular formula of the glass ceramic sulfide electrolyte is Li7P 3-x Me x S 11-2.5x-0.5y O ax I y ; Among them, Me represents a metal element, the value range of a is 1 ≤ a ≤ 3, the value range of x is 0 < x < 0.5, and the value range of y is 0 < y < 1.

2. The glass-ceramic sulfide electrolyte according to claim 1, characterized in that The value range of x is 0.05 ≤ x ≤ 0.3, and the value range of y is 0.1 ≤ y ≤ 0.

5.

3. The glass-ceramic sulfide electrolyte according to claim 1 or 2, characterized in that The Me includes any one of the following elements: W, Mn, Ca or Ba.

4. A method for preparing a glass ceramic sulfide electrolyte, characterized in that: The method includes: Li2S, P2S5, MeO a , LiI are mixed under an inert gas environment to obtain a precursor powder, wherein Me represents a metal element, a represents MeO a The number of oxygen atoms in the molecule, a, is in the range of 1≤a≤3; Performing an amorphization treatment on the precursor powder to obtain a precursor of the solid electrolyte powder; Sintering the precursor of the solid electrolyte powder in an inert gas environment to obtain a glass-ceramic sulfide electrolyte.

5. The method according to claim 4, characterized in that The MeO a Includes any of the following: WO3, MnO2, CaO or BaO.

6. The method according to claim 4 or 5, characterized in that The Li2S, P2S5, MeO a Before mixing LiI under an inert gas environment, the method further comprises: According to Li2S, P2S5, MeO a The molar ratio of LiI is (7-y):(3-x):2x:2y. Li2S, P2S5, MeO a 、LiI。 7. The method according to claim 6, characterized in that The value range of x is 0 < x < 0.5, and the value range of y is 0 < y < 1.

8. The method according to claim 7, characterized in that The value range of x is 0.05 ≤ x ≤ 0.3, and the value range of y is 0.1 ≤ y ≤ 0.

5.

9. The method according to claim 4 or 5, characterized in that The performing an amorphization treatment on the precursor powder to obtain a precursor of the solid electrolyte powder includes: Placing the precursor powder in a ball mill jar and performing ball milling using a ball mill to obtain the precursor of the solid electrolyte powder.

10. The method according to claim 9, characterized in that When performing ball milling, the ball milling time is 3 h to 50 h, and / or the ball milling speed is 100 rpm to 800 rpm.

11. The method according to claim 4 or 5, characterized in that When performing sintering, the sintering time is 1 h to 20 h, and / or the sintering temperature is 200°C to 400°C.

12. An all-solid-state battery, characterized in that: Includes: The glass-ceramic sulfide electrolyte according to any one of claims 1 to 3, and / or the glass-ceramic sulfide electrolyte prepared by the method according to any one of claims 4 to 11.

Images