A wet air stable sulfide solid state electrolyte, method of making and battery

Abstract

The application discloses a kind of sulfide solid electrolyte and its preparation method and battery stable in wet air, belong to the technical field of all-solid-state battery, sulfide solid electrolyte includes the following weight parts raw materials: sulfide solid electrolyte 20~100 parts, metal halide component 1 part, sulfide solid electrolyte chemical formula is Li 6‑x PS 5‑ x Cl 1+x ,0≤x≤0.6, metal halide component includes at least one metal halide, metal halide chemical formula is MX n ,2≤n≤4, M is one of Zr, Al, Zn, Sn, Sb and Bi, X is one of F, Cl, Br and I, the present application mixes the specific ratio of metal halide and sulfide solid electrolyte after ball milling and annealing treatment, obtains in-situ doping coating layer on the surface of sulfide solid electrolyte, effectively improves the wet air stability of sulfide solid electrolyte under the condition of less influence sulfide solid electrolyte ionic conductivity.

Description

Technical Field

[0001] This invention belongs to the field of all-solid-state battery technology, specifically relating to a humid air-stable sulfide solid electrolyte, its preparation method, and the battery thereof. Background Technology

[0002] Solid electrolytes are the core component of all-solid-state lithium batteries. Sulfide solid electrolytes, especially silver-germanium sulfide electrolyte materials (typically represented by Li6PS5Cl), are particularly valuable due to their superior ion conductivity (10). -3 -10 -2 Sulfide electrolytes are considered to have the greatest commercial potential due to their high resistance (S / cm) and mechanical ductility. Their unique low grain boundary resistance allows for densification through cold pressing, while also possessing excellent deformation capabilities, enabling the formation of a tight electrode-electrolyte interface within the battery and significantly reducing interfacial impedance. Furthermore, sulfide electrolytes do not contain flammable organic solvents, fundamentally eliminating the risk of thermal runaway in traditional lithium-ion batteries, and can increase battery energy density to >500 Wh / kg by matching lithium metal anodes with high-voltage cathodes. However, the industrialization of sulfide solid electrolytes still faces significant bottlenecks, with high sensitivity to air humidity being a major factor. The instability of sulfide solid electrolytes to humid air mainly stems from the chemical characteristics of the PS bonds in their crystal structure. According to the hard-soft acid-base theory (HSAB), sulfur ions (S... 2- (soft alkali) and phosphorus ions (P 5+ The combination of hard acids (and oxygen in water molecules, which is a hard base) is thermodynamically unstable, while oxygen in water molecules (hard base) readily combines with phosphorus (P). 5+ reaction.

[0003] For example, the electrolyte Li6PS5Cl undergoes a typical hydrolysis reaction upon contact with moisture in air: Li6PS5Cl + 6H2O → Li3PO4 + 2LiOH + 5H2S↑ + LiCl. This reaction not only causes the electrolyte structure to collapse but also releases highly toxic and corrosive hydrogen sulfide (H2S) gas. These defects of sulfide solid electrolytes necessitate that their synthesis, storage, and battery assembly be carried out in a strictly inert atmosphere (such as an argon glove box), significantly increasing production costs and hindering large-scale applications.

[0004] To address the aforementioned issues, current methods primarily involve doping and surface coating of sulfide solid electrolytes to modify the materials. For doping, the main approach is to introduce Sn. 4+ In 3+ and Sb 5+ Soft acids that substitute or partially substitute P 5+ O 2- Equal hard base partially replaces S 2-Enhanced bonding between cations and anions in sulfide electrolytes prevents moisture from reacting with them. Surface coating primarily achieves this isolation by coating or coupling hydrophobic polymers onto the sulfide surface. While these techniques improve the humid air stability of sulfides to some extent, they generally suffer from a common stability-conductivity weighting defect, with almost all modification methods sacrificing ionic conductivity. For example, constructing a coating layer on the electrolyte surface increases interfacial impedance, and doping the electrolyte bulk phase with stabilizing elements alters carrier concentration and lithium-ion transport paths, also reducing initial ionic conductivity. An ideal modification strategy should control the initial ionic conductivity loss to <20%, but in practice, it often reaches 30-50%. Therefore, developing a surface modification technology that combines high protection, low interfacial impedance, and mass production feasibility has become an urgent industry need. Summary of the Invention

[0005] One of the objectives of this invention is to provide a humid air-stable sulfide solid electrolyte to solve the problem that sulfide solid electrolytes in the prior art cannot simultaneously possess humid air stability and low interfacial impedance.

[0006] The second objective of this invention is to provide a method for preparing a humid air-stable sulfide solid electrolyte, which is used to prepare the aforementioned humid air-stable sulfide solid electrolyte.

[0007] A third objective of this invention is to provide a battery comprising the aforementioned humid air-stable sulfide solid electrolyte.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] A humid air-stable sulfide solid electrolyte comprises the following raw materials in parts by weight:

[0010] 20-100 parts of sulfide solid electrolyte and 1 part of metal halide component.

[0011] As a preferred technical solution of the present invention, the sulfide solid electrolyte has the chemical formula Li 6-x PS 5-x Cl 1+x , 0≤x≤0.6.

[0012] As a preferred embodiment of the present invention, the metal halide component comprises at least one metal halide, wherein the metal halide has the chemical formula MX. n , 2≤n≤4, M is one of Zr, Al, Zn, Sn, Sb and Bi, and X is one of F, Cl, Br and I.

[0013] As a preferred embodiment of the present invention, when the metal halide components are a mixture, the molar amounts of each metal halide in the metal halide components are equal.

[0014] The preparation method of the above-mentioned air-stable sulfide solid electrolyte includes the following steps:

[0015] S1. Pre-ball mill the metal halide, then mix and ball-mill the pre-ball-milled metal halide with the sulfide solid electrolyte to obtain a mixture;

[0016] S2. The mixture is annealed under an argon atmosphere, and then ball-milled again after annealing to obtain a sulfide solid electrolyte that is stable in humid air.

[0017] As a preferred technical solution of the present invention, the ball milling speed during the pre-milling process is 500-600 rpm and the ball milling time is 20-30 h.

[0018] As a preferred technical solution of the present invention, the ball milling speed is 200-300 rpm and the ball milling time is 5-10 h during the mixing ball milling process.

[0019] As a preferred technical solution of the present invention, the annealing temperature during the annealing process is 400-500℃, the annealing time is 2-5h, and the heating rate is 2-10℃ / min.

[0020] As a preferred technical solution of the present invention, the ball milling speed is 100-200 rpm and the ball milling time is 1-2 hours during the re-grinding process.

[0021] A battery, the battery being an all-solid-state battery, the all-solid-state battery comprising a positive electrode, a negative electrode, and a solid electrolyte layer located between the positive and negative electrodes, the solid electrolyte layer comprising the aforementioned humid air-stable sulfide solid electrolyte.

[0022] The beneficial effects of this invention are:

[0023] 1. This invention provides a humid air-stable sulfide solid electrolyte. It involves mixing a metal halide and a sulfide solid electrolyte in a specific ratio, ball milling, and then annealing to obtain an in-situ doped coating layer on the surface of the sulfide solid electrolyte. This coating layer effectively isolates the sulfide solid electrolyte from contact with moisture in the air, significantly improving its humid air stability with minimal impact on the ionic conductivity. This meets the requirements for widespread use in all-solid-state batteries and has broad application prospects and market potential.

[0024] 2. This invention employs a mixture of metal halide and sulfide electrolytes followed by annealing to form an in-situ coating layer doped with metal and halogen elements on the surface of the sulfide electrolyte. Because the phase structure is similar to that of the sulfide electrolyte, it exhibits certain ionic conductivity, overcoming the problem of blocked lithium-ion transport channels on the material surface caused by traditional polymer surface coating. It also avoids the significant decrease in ionic conductivity caused by doping the entire bulk material. This method is simple and effective, the obtained material is easy to prepare, has low production costs, good air stability, and high lithium-ion conductivity, and holds promise for solving the practical application problem of inorganic sulfide electrolytes as high-performance all-solid-state lithium secondary battery electrolytes.

[0025] 3. This invention strictly controls the ratio of sulfide solid electrolyte and metal halide. When the amount of metal halide is too low, the coating layer formed does not significantly improve the stability of humid air. When the amount of metal halide is too high, although the coating layer formed has a significant effect on improving the stability of humid air, it will significantly affect the ionic conductivity. Attached Figure Description

[0026] The invention will now be further described with reference to the accompanying drawings.

[0027] Figure 1 These are SEM and EDS images of the humid air-stable sulfide solid electrolyte obtained in Example 1 of this invention;

[0028] Figure 2 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Example 1 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0029] Figure 3 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Example 2 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0030] Figure 4 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Example 3 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0031] Figure 5 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Example 4 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0032] Figure 6 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Example 5 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0033] Figure 7 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Example 6 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0034] Figure 8 This is a comparison of the ionic conductivity of the original sulfide solid electrolyte of Comparative Example 1 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0035] Figure 9 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Comparative Example 2 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0036] Figure 10 This is a comparison of the ionic conductivity of the humid air-stable sulfide solid electrolyte obtained in Comparative Example 3 of the present invention before and after exposure to air with a relative humidity of 5% for 30 minutes.

[0037] Figure 11 This is a comparison of the ionic conductivity of the bulk doped sulfide solid electrolyte, which is stable in humid air and obtained in Comparative Example 4 of this invention, before and after exposure to air with a relative humidity of 5% for 30 minutes. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] Obviously, the following description is merely some examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios without any inventive effort. Furthermore, it is understood that although the effort involved in such development may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, any changes to design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as insufficient disclosure of the content of this application.

[0040] However, there may be instances where unnecessary detailed descriptions are omitted. For example, detailed descriptions of well-known matters or repetitive descriptions of essentially the same structure may be omitted. This is to avoid making the following description unnecessarily lengthy and to facilitate understanding by those skilled in the art. Furthermore, the following description is provided to enable those skilled in the art to fully understand this application and is not intended to limit the subject matter of the claims.

[0041] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions, and all technical features and optional technical features of this application can be combined to form new technical solutions.

[0042] Previous methods for improving the humid air stability of sulfide solid electrolytes have almost always come at the cost of sacrificing ionic conductivity. Therefore, this application provides a humid air-stable sulfide solid electrolyte, its preparation method, and a battery. The method involves mixing a metal halide with a sulfide electrolyte and then annealing the mixture to form an in-situ coating layer doped with metal and halogen elements on the surface of the sulfide electrolyte. Because the phase structure is similar to that of the sulfide electrolyte, this coating layer exhibits a certain degree of ionic conductivity, overcoming the problem of blocked lithium-ion transport channels on the material surface caused by traditional polymer surface coating. It also avoids the significant decrease in bulk lithium-ion conductivity caused by doping the entire bulk material.

[0043] For ease of explanation, the following examples illustrate a humid air-stable sulfide solid electrolyte, its preparation method, and a battery.

[0044] A humid air-stable sulfide solid electrolyte comprises the following raw materials in parts by weight:

[0045] 20-100 parts of sulfide solid electrolyte and 1 part of metal halide component.

[0046] In some embodiments, the sulfide solid electrolyte has the chemical formula Li 6-x PS 5-x Cl 1+x , 0≤x≤0.6.

[0047] In some embodiments, the metal halide component comprises at least one metal halide with the chemical formula MX. n , 2≤n≤4, M is one of Zr, Al, Zn, Sn, Sb and Bi, and X is one of F, Cl, Br and I.

[0048] In some embodiments, when the metal halide component is a mixture, the molar amounts of each metal halide in the metal halide component are equal.

[0049] The preparation method of the above-mentioned air-stable sulfide solid electrolyte includes the following steps:

[0050] S1. Pre-ball mill the metal halide, then mix and ball-mill the pre-ball-milled metal halide with the sulfide solid electrolyte to obtain a mixture;

[0051] S2. The mixture is annealed under an argon atmosphere, and then ball-milled again after annealing to obtain a sulfide solid electrolyte that is stable in humid air.

[0052] In some embodiments, the ball milling speed during the pre-milling process is 500-600 rpm, and the ball milling time is 20-30 h.

[0053] In some embodiments, the ball milling speed is 200-300 rpm and the ball milling time is 5-10 h during the mixing ball milling process.

[0054] In some embodiments, the annealing temperature during the annealing process is 400–500°C, the annealing time is 2–5 h, and the heating rate is 2–10°C / min.

[0055] In some embodiments, the ball milling speed is 100-200 rpm and the ball milling time is 1-2 hours during the re-grinding process.

[0056] A battery, the battery being an all-solid-state battery, the all-solid-state battery comprising a positive electrode, a negative electrode, and a solid electrolyte layer located between the positive and negative electrodes, the solid electrolyte layer comprising the aforementioned humid air-stable sulfide solid electrolyte.

[0057] The following is a detailed description with reference to specific examples.

[0058] Example 1

[0059] A method for preparing a humid air-stable sulfide solid electrolyte includes the following steps:

[0060] S1. Place 1g of SbCl3 in a ball mill jar and ball mill at 550rpm for 25h to complete the pre-ball milling. Mix 0.1g of the pre-ball milled SbCl3 with 10g of Li6PS5Cl and ball mill at 550rpm for 8h to obtain the mixture.

[0061] S2. Place the mixture in a tube furnace and heat it to 450°C at a heating rate of 5°C / min under an argon atmosphere. Hold the temperature for 3 hours and then cool it to room temperature with the furnace. Ball mill it again at a ball milling speed of 100 rpm for 1 hour to obtain a humid air-stable sulfide solid electrolyte.

[0062] The air-stable sulfide solid electrolyte obtained in Example 1 was analyzed using scanning electron microscopy and energy dispersive spectroscopy. The results are as follows: Figure 1 As shown, Figure 1 In the image, 'a' is a scanning electron microscope (SEM) image. Figure 1 Figure b shows the sulfur element detection chart. Figure 1 In the middle, c represents the phosphorus detection graph. Figure 1 In the diagram, d represents the detection pattern for antimony. Figure 1 In the image, 'e' represents the chlorine element detection graph, which is derived from... Figure 1It can be seen that there is a clear Cl-rich distribution on the particle surface, and the Sb distribution on the particle surface can also be observed.

[0063] The sulfide solid electrolyte product obtained in Example 1 was exposed to air at 5% relative humidity for 30 minutes, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 2 As shown, by Figure 2 It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 2.45 mS / cm, and the room temperature ionic conductivity after exposure was 0.92 mS / cm.

[0064] Example 2

[0065] A method for preparing a humid air-stable sulfide solid electrolyte differs from Example 1 only in that "mixing 0.1g of pre-ball-milled SbCl3 with 10g of Li6PS5Cl" in Example 1 is replaced with "mixing 0.1g of pre-ball-milled SbCl3 with 5g of Li6PS5Cl".

[0066] The sulfide solid electrolyte product obtained in Example 2 was exposed to air at 5% relative humidity for 30 minutes, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 3 As shown, by Figure 3 It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 2.41 mS / cm, and the room temperature ionic conductivity after exposure was 1.92 mS / cm.

[0067] Example 3

[0068] A method for preparing a humid air-stable sulfide solid electrolyte differs from Example 1 only in that "mixing 0.1g of pre-ball-milled SbCl3 with 10g of Li6PS5Cl" in Example 1 is replaced with "mixing 0.1g of pre-ball-milled SbCl3 with 2g of Li6PS5Cl".

[0069] The sulfide solid electrolyte product obtained in Example 3 was exposed to air at 5% relative humidity for 30 minutes, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 4 As shown, by Figure 4 It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 2.30 mS / cm, and the room temperature ionic conductivity after exposure was 1.87 mS / cm.

[0070] Example 4

[0071] A method for preparing a humid air-stable sulfide solid electrolyte, which differs from Example 2 only in that “SbCl3” in Example 2 is replaced with an equal mass of “BiCl3”.

[0072] The sulfide solid electrolyte product obtained in Example 4 was exposed to air at 5% relative humidity for 30 minutes, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 5 As shown, by Figure 5 It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 2.41 mS / cm, and the room temperature ionic conductivity after exposure was 1.89 mS / cm.

[0073] Example 5

[0074] A method for preparing a humid air-stable sulfide solid electrolyte differs from Example 2 only in that “SbCl3” in Example 2 is replaced with an equal mass of “a mixture composed of equimolar amounts of BiCl3 and SbCl3”.

[0075] The sulfide solid electrolyte product obtained in Example 5 was exposed to air at 5% relative humidity for 30 minutes, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 6 As shown, by Figure 6 It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 2.40 mS / cm, and the room temperature ionic conductivity after exposure was 1.91 mS / cm.

[0076] Example 6

[0077] A method for preparing a humid air-stable sulfide solid electrolyte differs from Example 2 only in that “SbCl3” in Example 2 is replaced with an equal mass of “SnCl2”.

[0078] The sulfide solid electrolyte product obtained in Example 6 was exposed to air at 5% relative humidity for 30 minutes, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 7 As shown, by Figure 7 It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 2.38 mS / cm, and the room temperature ionic conductivity after exposure was 1.90 mS / cm.

[0079] Comparative Example 1

[0080] This comparative example is the original Li6PS5Cl without any treatment.

[0081] The raw Li6PS5Cl was exposed to air at 5% relative humidity for 30 min, and its room temperature ionic conductivity before and after air exposure was measured. The results are as follows: Figure 8 As shown, by Figure 8 It can be seen that the room temperature ionic conductivity of the original Li6PS5Cl before exposure was 2.50 mS / cm, and the room temperature ionic conductivity after exposure was 0.33 mS / cm.

[0082] Compared with Comparative Example 1, the ionic conductivity of the humid air-stable sulfide solid electrolytes prepared in Examples 1-6 before exposure was about 92% to 98% of that of the original Li6PS5Cl, indicating that the effect of in-situ surface doping on the initial ionic conductivity was small, and the ionic conductivity after exposure to humid air was significantly better than that of the original Li6PS5Cl.

[0083] Comparative Example 2

[0084] A method for preparing a humid air-stable sulfide solid electrolyte differs from Example 1 only in that "mixing 0.1g of pre-ball-milled SbCl3 with 10g of Li6PS5Cl" in Example 1 is replaced with "mixing 0.1g of pre-ball-milled SbCl3 with 20g of Li6PS5Cl".

[0085] The sulfide solid electrolyte product obtained in Comparative Example 2 was exposed to air at 5% relative humidity for 30 min, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 9 As shown, by Figure 9 It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 2.50 mS / cm, and the room temperature ionic conductivity after exposure was 0.35 mS / cm.

[0086] Comparative Example 3

[0087] A method for preparing a humid air-stable sulfide solid electrolyte differs from Example 1 only in that "mixing 0.1g of pre-ball-milled SbCl3 with 10g of Li6PS5Cl" in Example 1 is replaced with "mixing 0.1g of pre-ball-milled SbCl3 with 1g of Li6PS5Cl".

[0088] The sulfide solid electrolyte product obtained in Comparative Example 3 was exposed to air at 5% relative humidity for 30 min, and its room temperature ionic conductivity before and after air exposure was tested. The results are as follows: Figure 10 As shown, by Figure 10It can be seen that the room temperature ionic conductivity of the sulfide solid electrolyte product before exposure was 1.96 mS / cm, and the room temperature ionic conductivity after exposure was 1.67 mS / cm. This result indicates that when an excess of SbCl3 is added, for example, when the mass ratio with Li6PS5Cl is 1:10, although the stability of the electrolyte in moist air can still be improved, the initial ionic conductivity of the electrolyte before exposure to air is significantly affected, and is only 78.4% of that of the original Li6PS5Cl material compared with Comparative Example 1.

[0089] Comparative Example 4

[0090] This comparative example uses Li₂S, P₂S₅, LiCl, and SbCl₃ as raw materials to synthesize a humid air-stable bulk-doped solid electrolyte, Li₆P₅. 0.944 Sb 0.056 S5Cl, the molar ratio of Sb to P in this electrolyte is the same as in Example 3.

[0091] The Li6P obtained in Comparative Example 4 0.944 Sb 0.056 S5Cl was exposed to air at 5% relative humidity for 30 minutes, and its room temperature ionic conductivity before and after air exposure was measured. The results are as follows: Figure 11 As shown, by Figure 11 It can be seen that the bulk-doped sulfide solid electrolyte Li6P 0.94 Sb 0.06 The room temperature ionic conductivity of S5Cl before exposure was 1.56 mS / cm, and the room temperature ionic conductivity after exposure was 1.32 mS / cm. This result shows that although bulk doping is beneficial to improving the humid air stability of the electrolyte, it has a great influence on the initial ionic conductivity before exposure. Compared with Comparative Example 1, it is only 62.4% of the original Li6PS5Cl material.

[0092] In summary, this invention employs a specific ratio of metal halide and sulfide solid electrolyte mixed, ball-milled, and then annealed to obtain an in-situ doped coating layer on the surface of the sulfide solid electrolyte. The phase structure of this coating layer is similar to that of the sulfide electrolyte, thus exhibiting a certain degree of ionic conductivity. This overcomes the problem of blocked lithium-ion transport channels on the material surface caused by traditional polymer surface coating, while also avoiding the significant decrease in ionic conductivity resulting from doping the entire bulk phase of the material. The resulting electrolyte material, with its coating layer effectively isolating moisture in the air from contact with the sulfide solid electrolyte bulk phase, effectively improves the humid air stability of the sulfide solid electrolyte with minimal impact on its ionic conductivity. This meets the requirements for the widespread use of all-solid-state batteries and has broad application prospects and market potential.

[0093] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0094] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A humid air-stable sulfide solid electrolyte, characterized in that, Including the following parts by weight of raw materials: 20-100 parts of sulfide solid electrolyte and 1 part of metal halide component; The sulfide solid electrolyte has the chemical formula Li. 6-x PS 5-x Cl 1+x , 0≤x≤0.6; The metal halide component includes at least one metal halide with the chemical formula MX. n , 2≤n≤4, M is one of Zr, Al, Zn, Sn, Sb and Bi, and X is one of Cl, Br and I; The humid air-stabilized sulfide solid electrolyte is obtained by ball milling and annealing a mixture of metal halide components and sulfide solid electrolyte to obtain an in-situ doped coating layer on the surface of the sulfide solid electrolyte. The annealing temperature during the annealing process is 400-500℃.

2. The humid air-stabilized sulfide solid electrolyte according to claim 1, characterized in that, When the metal halide components are a mixture, the molar amounts of each metal halide in the metal halide components are equal.

3. A method for preparing a humid air-stabilized sulfide solid electrolyte, characterized in that, The preparation of the air-stable sulfide solid electrolyte according to any one of claims 1-2 includes the following steps: S1. Pre-ball mill the metal halide, then mix and ball-mill the pre-ball-milled metal halide with the sulfide solid electrolyte to obtain a mixture; S2. The mixture is annealed under an argon atmosphere, and then ball-milled again after annealing to obtain a sulfide solid electrolyte that is stable in humid air.

4. The method for preparing a humid air-stabilized sulfide solid electrolyte according to claim 3, characterized in that, During the pre-milling process, the ball milling speed is 500-600 rpm and the ball milling time is 20-30 hours.

5. The method for preparing a humid air-stabilized sulfide solid electrolyte according to claim 3, characterized in that, During the mixing and ball milling process, the ball milling speed is 200-300 rpm and the ball milling time is 5-10 hours.

6. The method for preparing a humid air-stabilized sulfide solid electrolyte according to claim 3, characterized in that, The annealing time is 2 to 5 hours, and the heating rate is 2 to 10 °C / min.

7. The method for preparing a humid air-stabilized sulfide solid electrolyte according to claim 3, characterized in that, During the re-grinding process, the ball mill speed is 100-200 rpm and the ball milling time is 1-2 hours.

8. A battery, characterized in that, The battery is an all-solid-state battery, which includes a positive electrode, a negative electrode, and a solid electrolyte layer located between the positive and negative electrodes. The solid electrolyte layer includes the humid air-stable sulfide solid electrolyte as described in any one of claims 1-2.

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