Sulfide solid electrolyte membrane and preparation method therefor, and all-solid-state alkali metal ion battery

Abstract

The present disclosure belongs to the technical field of all-solid-state batteries. Provided are a sulfide solid electrolyte membrane and a preparation method therefore, and an all-solid-state alkali metal ion battery. The sulfide solid electrolyte membrane is composed of sulfide particles containing a polymer coating, and the chemical composition of the sulfide particles containing a polymer coating is [EmMnSo]CαOβSγHδNζEa.

Description

Sulfide solid electrolyte membrane and preparation method thereof and all-solid-state alkali metal ion battery

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure is based on and claims the priority of Chinese patent application with application number 202311799872.4 and application date December 26, 2023. The entire content of the Chinese patent application is hereby incorporated into this disclosure as a reference. Technical Field

[0003] The present disclosure belongs to the technical field of all-solid-state batteries, and particularly relates to a sulfide solid electrolyte membrane and a preparation method thereof, and an all-solid-state alkali metal ion battery. Background Art

[0004] Current commercial alkali metal ion batteries are generally liquid lithium-ion batteries using liquid organic electrolytes. However, liquid organic electrolytes are flammable and volatile, and under conditions of abuse such as overcharging and impact, liquid batteries are prone to safety accidents such as violent combustion. In comparison, all-solid-state alkali metal ion batteries using solid electrolyte membranes offer greater safety and can be matched with alkali metal electrodes to achieve higher energy density. Therefore, as a next-generation energy storage device, the development of all-solid-state alkali metal ion batteries has attracted great attention from academia and industry.

[0005] There are many types of solid electrolyte membranes for all-solid-state alkali metal ion batteries. Among them, sulfide solid electrolyte membranes have high ionic conductivity and easy processability. They can be in close contact with active materials through cold pressing to achieve low interface resistance. They are considered to be the most promising solid electrolyte membranes. However, the current sulfide solid electrolyte membranes (sulfide solid electrolytes such as Li3PS4, Li6PS5Cl, Li 10 GeP2S 12 The compatibility of sulfide solid electrolyte membrane with commercial high voltage cathode materials (such as lithium cobalt oxide, ternary high nickel cathode materials, lithium nickel manganese oxide, etc.) is very poor, which is attributed to the fact that sulfide solid electrolyte membrane is easy to remove Li at high voltage. + Cause S 2- Oxidation produces a series of high-interfacial impedance products, such as elemental sulfur, which severely restricts ion transport at the cathode / electrolyte membrane interface. To date, the preparation of sulfide solid electrolyte membranes (with a binder content of <10 wt%) that possess low cost, excellent mechanical properties, high-voltage resistance, and high ionic conductivity remains a challenge. This is closely related to the inherent thermodynamic instability of sulfide solid electrolyte particles and the lack of binder systems that are compatible with sulfide solid electrolytes.

[0006] In response to the above problems, a lot of research has been conducted in related technologies. For example, patent application document 202211153228.5 discloses a lithium ion conductive binder and its preparation method, a sulfide electrolyte membrane and its preparation method, and a lithium battery. The binder of the sulfide solid electrolyte membrane is a styrene-butadiene-styrene block copolymer grafted with lithium carboxylate, which has strong viscosity and can improve the ionic conductivity of the sulfide solid electrolyte membrane. Patent application document 202211374919.8 discloses a composite solid electrolyte membrane and its preparation method and a solid-state lithium battery. The solid electrolyte membrane includes a core-shell structure PVDF-HFP@PI nanofiber membrane and an electrolyte composed of a lithium ion conductor, a polymer and a lithium salt filled into its pores. The solid electrolyte membrane has excellent mechanical properties and thermal dimensional stability. Patent application document 202111591792.0 discloses a method for preparing an all-solid-state battery with a lithium-supplemented sulfide solid electrolyte membrane. The sulfide solid electrolyte membrane selects nitrile rubber as a binder and uses an electrostatic powder spraying device to sprinkle inert lithium powder on the surface of the sulfide electrolyte layer. While achieving negative electrode lithium replenishment, it can also improve the interface contact between the solid electrolyte membrane and the negative electrode plate, reduce the interfacial impedance of the battery, and improve its rate performance and capacity retention rate.

[0007] For example, patent application document 202211739119.1 discloses a sulfide-polymer composite solid electrolyte membrane prepared by molecular hybridization, its preparation method and application. The patent obtains a molecular hybrid sulfide-polymer composite solid electrolyte membrane through the thiol-olefin reaction of polyethylene glycol diacrylate and sulfide electrolyte. This method of internal molecular hybridization can greatly improve the interface compatibility problem between organic electrolytes and inorganic electrolytes, and greatly reduce the internal impedance. Patent application document 202211439068.0 discloses a method for preparing a high-concentration lithium salt sulfide composite solid electrolyte membrane and its application. The binder of the solid electrolyte membrane includes one or more copolymers of butyl acrylate, ethyl acrylate, polyethylene glycol diacrylate, and polymethyl methacrylate. The film has the advantages of low porosity, high ion conductivity, high migration number, good contact with lithium metal, etc., and the preparation process is simple, does not require a large amount of organic solvents, and can be used for large-scale production. Patent application document 202011597001.0 discloses an electrolyte membrane for sulfide solid-state batteries, its preparation method and use. The sulfide solid-state electrolyte membrane uses any one of polyethylene isolation membrane, polypropylene isolation membrane, polyethylene-polypropylene composite isolation membrane, polyethylene terephthalate non-woven isolation membrane or polyimide electrospun isolation membrane or a combination of at least two as the base membrane, and a nano-ceramic layer is coated on both sides of the base membrane to make the electrolyte membrane have high interface contact, high strength, and high ionic conductivity.

[0008] However, while the sulfide solid electrolyte membranes disclosed in the aforementioned related art possess high ionic conductivity and excellent mechanical properties, they still face compatibility issues with high-voltage cathodes. Therefore, developing sulfide solid electrolyte membranes suitable for high-voltage cathode systems remains a long and arduous task. Summary of the Invention

[0009] The present disclosure is based on the inventors' discovery and understanding of the following facts and problems: the insufficient compatibility between sulfide electrolyte and high-voltage positive electrode is related to the thermodynamic instability of the surface defects of sulfide particles (containing a large number of thiol functional groups). The inventors have found that by first synthesizing high-voltage resistant sulfide particles and then functionalizing the surface of the sulfide particles to further improve the thermodynamic stability of the sulfide particles, it is expected to solve the compatibility of sulfide solid electrolyte membranes with high-voltage positive electrodes.

[0010] The present disclosure aims to solve at least one of the technical problems in the related art to a certain extent. To this end, embodiments of the present disclosure provide a sulfide solid electrolyte membrane, a preparation method thereof, and an all-solid-state alkali metal ion battery.

[0011] The embodiment of the present disclosure provides a sulfide solid electrolyte membrane, which is composed of sulfide particles containing a polymer coating. The chemical composition of the sulfide particles containing the polymer coating is [E m M n S o ]C α O β S γ H δ N ζ E a ; Among them, [E m M n S o ] is a sulfide particle, E is selected from Li + Or Na + , M is selected from Si 4+ 、Ge 4+ 、Se 4+ or Sn 4+ , and 3≤m≤8, 1≤n≤2, 2≤o≤8; C α O β S γ H δ N ζ E a It is a polymer coating that forms a persulfide bond with the surface of the sulfide particle, and α is selected from 0.0001-1, β is selected from 0-0.5, γ is selected from 0.000001-1, δ is selected from 0.00001-2, ζ is selected from 0-0.01, and a is selected from 0-0.0001.

[0012] The advantages and technical effects brought by the sulfide solid electrolyte membrane of the embodiment of the present disclosure are:

[0013] (1) Sulfide particles [E m M n S o ] has high-voltage resistance, which helps to improve the high-voltage resistance of the sulfide solid electrolyte membrane of the embodiment of the present disclosure.

[0014] (2) Since the polymer coating is connected to the surface of the sulfide particles through persulfide bonds (SS bonds) in the sulfide particles containing the polymer coating, a cross-linked network structure is formed inside the entire sulfide solid electrolyte membrane. The polymer coating forms an "artificial protective layer" with high oxidation stability on the surface of the sulfide particles, thereby improving the thermodynamic stability of the high-voltage positive electrode, thereby improving the compatibility of the sulfide solid electrolyte membrane and the high-voltage positive electrode of the embodiment of the present disclosure.

[0015] (3) Due to the SS bond on the surface of sulfide particles, the electron cloud density on S will increase significantly, which will enhance the interaction between S and alkali metal ions. Under high voltage conditions, the strong interaction between S and alkali metal ions will kinetically limit the alkali metal ions from being released from the electrolyte, thus limiting the S 2- oxidation, thereby improving the high-voltage stability of the sulfide solid electrolyte membrane of the embodiment of the present disclosure, giving it a wider electrochemical window, and improving the high-voltage cycle performance of the all-solid-state alkali metal ion battery.

[0016] (4) The abundant SS bonds have a reversible fracture-generation function at room temperature, which can provide the sulfide solid electrolyte membrane of the embodiment of the present disclosure with excellent self-repairing ability, ensuring the mechanical stability of the sulfide solid electrolyte membrane structure and its close contact with the electrode during battery cycling, thereby improving the cycle stability and rate performance of the battery.

[0017] (5) The solid sulfide electrolyte design of the embodiment of the present disclosure can make the sulfide solid electrolyte membrane have excellent ionic conductivity, which can ensure good ion transmission performance of the electrode interface and improve the cycle stability and rate performance of the all-solid-state alkali metal ion battery.

[0018] (6) The sulfide solid electrolyte membrane of the embodiment of the present disclosure does not undergo obvious chemical / electrochemical side reactions with the high-voltage positive electrode active material, and can effectively buffer the volume change of the positive electrode active material during the charging and discharging process, so that the all-solid-state alkali metal ion battery has good interface contact throughout the entire charging and discharging cycle, reducing the interfacial impedance of the battery and improving the cycle stability and rate performance of the battery.

[0019] In some embodiments, based on the total mass of the sulfide solid electrolyte membrane being 100%, the mass fraction of the sulfide particles is 80-99%, and the mass fraction of the polymer coating is 1-20%.

[0020] In some embodiments, the sulfide solid electrolyte membrane has a thickness of 15-35 μm.

[0021] In addition, the present disclosure also provides a method for preparing a sulfide solid electrolyte membrane, comprising the following steps:

[0022] S1. The sulfide particles and the binder are mixed and ball-milled in a dry atmosphere to obtain the sulfide particles containing the polymer coating; the binder is a polymer containing a terminal thiol and a persulfide bond structure;

[0023] S2. hot-pressing the sulfide particles containing the polymer coating to obtain the sulfide solid electrolyte membrane.

[0024] The advantages and technical effects brought by the preparation method of the embodiment of the present disclosure are:

[0025] (1) Compared with the sulfide solid electrolyte membranes in the related art, the sulfide solid electrolyte membrane provided by the present disclosure has excellent ionic conductivity (e.g., 0.5-8 mS / cm) and mechanical properties (e.g., 10-100 MPa tensile strength), a wide electrochemical window (e.g., 5.5-6.0 V vs Li / Li + ) and does not undergo obvious chemical / electrochemical side reactions with high-voltage positive electrode active materials, which can significantly improve the performance of high-voltage all-solid-state batteries; this advantage is related to the persulfide bonds formed between the binder containing terminal thiol and persulfide bond structures and the surface of sulfide particles, as well as the high self-repairing ability of the system itself.

[0026] (2) In the preparation method of the embodiment of the present disclosure, ball milling treatment is required in step (1), and the terminal thiol in the binder and the thiol functional groups on the surface of the sulfide particles form persulfide bonds under ball milling conditions; if a simple mixing method is used, the uniform distribution of the sulfide particles cannot be achieved, which will affect the performance of the sulfide solid electrolyte membrane.

[0027] (3) In the preparation method of the embodiment of the present disclosure, the ball milling treatment in step (1) is carried out in a dry atmosphere to avoid deterioration of the sulfide particles.

[0028] In some embodiments, in step S1, the general structural formula of the binder is formula (1):

[0029] wherein x is selected from 10-1000, y and z are independently selected from 0-2000;

[0030] A and C are each independently selected from H, Cl, CN or methyl;

[0031] B and D are independently selected from an alkoxycarbonyl group having less than ten carbon atoms, a cyano group, a carbamoyl group, a group having less than ten carbon atoms and containing a terminal carboxylate structure, a group represented by formula (2), a group represented by formula (3), or a group represented by formula (4), wherein w in formula (2) and formula (3) is independently selected from 0 to 100;

[0032] R is selected from an alkyl group with less than ten carbon atoms containing a terminal mercapto group, a terminal hydroxyl group, a terminal methanesulfonyl group, a terminal cyano group, a terminal alkoxyphosphoryl group, a terminal carboxylic acid group or a terminal carboxylic acid derivative group.

[0033] In some embodiments, in step S1, the mass ratio of the sulfide particles to the binder is (80-99):(1-20).

[0034] In some embodiments, in step S1, the ball milling process is performed at a speed of 2000 r / min or more and for a time of 1 h or more.

[0035] In some embodiments, in step S1, the ball milling process is performed at a speed of 2000-10000 r / min for a time of 1-24 h.

[0036] In some embodiments, in step S2, the pressure of the hot pressing treatment is above 100 MPa.

[0037] In addition, an embodiment of the present disclosure also provides an all-solid-state alkali metal ion battery, comprising the sulfide solid electrolyte membrane of the embodiment of the present disclosure, or the sulfide solid electrolyte membrane obtained by the preparation method of the embodiment of the present disclosure.

[0038] The advantages and technical effects of the all-solid-state alkali metal ion battery of the present disclosure are as follows:

[0039] The all-solid-state alkali metal ion battery of the embodiment of the present disclosure has excellent cycle stability and rate performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG1 is a schematic diagram of the reaction of forming SS bonds between a binder and the surface of sulfide particles in the preparation method disclosed herein;

[0041] FIG2 shows the long cycle performance of the all-solid-state lithium-ion batteries of Application Example 2 and Application Comparative Example 2 at room temperature;

[0042] FIG3 shows the long cycle performance of the all-solid-state lithium-ion batteries of Application Example 3 and Application Comparative Example 3 at room temperature;

[0043] FIG4 shows the long cycle performance of the all-solid-state lithium-ion batteries of Application Example 5 and Application Comparative Example 5 at room temperature;

[0044] FIG5 shows the long cycle performance of the all-solid-state lithium-ion batteries of Application Example 6 and Application Comparative Example 6 at room temperature. DETAILED DESCRIPTION

[0045] The embodiments of the present disclosure are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present disclosure, but should not be understood as limiting the present disclosure.

[0046] A sulfide solid electrolyte membrane is composed of sulfide particles containing a polymer coating, wherein the chemical composition of the sulfide particles containing the polymer coating is [E m M n S o ]C α O β S γ H δ N ζ E a ; Among them, [E m M n S o ] is a sulfide particle, E is selected from Li + Or Na + , M is selected from Si 4+ 、Ge 4+ 、Se 4+ or Sn 4+ , and 3≤m≤8, 1≤n≤2, 2≤o≤8; C α O β S γ H δ N ζ E a It is a polymer coating that forms a persulfur covalent bond with the surface of the sulfide particles, and α is selected from 0.0001-1, β is selected from 0-0.5, γ is selected from 0.000001-1, δ is selected from 0.00001-2, ζ is selected from 0-0.01, and a is selected from 0-0.0001.

[0047] The SS bonds formed between the polymer coating and the surface of the sulfide particles form a cross-linked network structure inside the entire sulfide solid electrolyte membrane, allowing the polymer coating to form an "artificial protective layer" with high oxidation stability on the surface of the sulfide particles, thereby improving the thermodynamic stability with the high-voltage positive electrode. In addition, due to the SS bonds on the surface of the sulfide particles, the electron cloud density on S will increase significantly, thereby enhancing the interaction between S and Li. Under high voltage conditions, the strong interaction between S and Li kinetically limits the escape of Li+ from the electrolyte, limiting the S 2-The oxidation of the positive electrode material is prevented, thereby improving the high-voltage stability of the sulfide solid electrolyte membrane. At the same time, the abundant persulfide bonds can also make the entire sulfide solid electrolyte membrane have excellent self-repairing ability, which can withstand the stress caused by the volume expansion of the electrode and maintain the integrity of the sulfide solid electrolyte membrane structure. The sulfide solid electrolyte membrane disclosed in the present invention can effectively buffer the volume change of the positive electrode active material during the charge and discharge process, so that the battery has good interface contact throughout the charge and discharge cycle. In addition, the high ionic conductivity of the electrolyte membrane can ensure good ion transmission performance at the electrode interface, improving the cycle stability and rate performance of the battery.

[0048] In some embodiments, based on the total mass of the sulfide solid electrolyte membrane being 100%, the mass fraction of the sulfide particles is 80-99%, and the mass fraction of the polymer coating is 1-20%. When the mass fraction of the sulfide particles is too low and the mass fraction of the polymer coating is too high, it is not conducive to improving the ion transport performance of the sulfide solid electrolyte membrane. When the mass fraction of the sulfide particles is too high and the mass fraction of the polymer coating is too low, it is not conducive to improving the mechanical properties of the sulfide solid electrolyte membrane.

[0049] In some embodiments, the sulfide solid electrolyte membrane has a thickness of 15-35 μm. When the membrane thickness is too low, it is not conducive to improving the cycling performance of the all-solid-state alkali metal ion battery, and the battery is prone to internal short circuits, leading to battery safety accidents. When the membrane thickness is too thick, it is not conducive to improving the rate performance of the all-solid-state alkali metal ion battery.

[0050] In addition, the present disclosure also provides a method for preparing a sulfide solid electrolyte membrane, comprising the following steps:

[0051] S1. The sulfide particles and the binder are mixed and ball-milled in a dry atmosphere to obtain the sulfide particles containing the polymer coating; the binder is a polymer containing a terminal thiol and a persulfide bond structure;

[0052] S2. hot-pressing the sulfide particles containing the polymer coating to obtain the sulfide solid electrolyte membrane.

[0053] Sulfide particles [E m M n S o] is a sulfide electrolyte that is resistant to high voltage; at the same time, as shown in Figure 1, in the ball milling treatment of step (1), the binder containing terminal thiol and persulfide bond structure can form SS bonds to construct a protective layer on the surface of the sulfide particles, thereby improving the thermodynamic stability of the high-voltage positive electrode, and thus synergistically improving the compatibility of the sulfide solid electrolyte membrane with the high-voltage positive electrode. Compared with the sulfide solid electrolyte membrane in the related art, due to the SS bonds on the surface of the sulfide particles, the electron cloud density on S will increase significantly, thereby enhancing the interaction between S and alkali metal ions. Under high voltage conditions, the strong interaction between S and alkali metal ions limits the alkali metal ions from the electrolyte from a kinetic point of view, limiting S 2- The oxidation of the sulfide solid electrolyte membrane improves the high-voltage stability of the sulfide solid electrolyte membrane. Moreover, the abundant SS bonds in the binder and the new SS bonds formed between the binder and the sulfide particles have a reversible break-regeneration function at room temperature, which can provide the solid sulfide electrolyte membrane with self-healing ability, ensuring the mechanical stability of the electrolyte membrane structure and its close contact with the electrode during battery cycling.

[0054] It should be noted that in the preparation method of the present embodiment, the ball milling treatment in step (1) is carried out in a dry atmosphere to prevent the sulfide particles from deteriorating. There is no particular limitation on the specific type of gas used in the dry atmosphere, as long as it does not react with the sulfide particles, the binder, and the sulfide solid electrolyte membrane and can ensure safety. For example, it can be an inert gas such as argon or nitrogen, or it can also be a mixture of oxygen or air and an inert gas. When the dry atmosphere contains oxygen or air, the proportion of oxygen or air should not be too high to avoid explosion.

[0055] In some embodiments, in step S1, the general structural formula of the binder is formula (1):

[0056] wherein x is selected from 10-1000, y and z are independently selected from 0-2000;

[0057] A and C are each independently selected from H, Cl, CN or methyl;

[0058] B and D are independently selected from an alkoxycarbonyl group having less than ten carbon atoms, a cyano group, a carbamoyl group, a group having less than ten carbon atoms and containing a terminal carboxylate structure, a group represented by formula (2), a group represented by formula (3), or a group represented by formula (4), wherein w in formula (2) and formula (3) is independently selected from 0 to 100;

[0059] R is selected from an alkyl group with less than ten carbon atoms containing a terminal mercapto group, a terminal hydroxyl group, a terminal methanesulfonyl group, a terminal cyano group, a terminal alkoxyphosphoryl group, a terminal carboxylic acid group or a terminal carboxylic acid derivative group.

[0060] The binder having the general structural formula (1) can more effectively improve the compatibility of the sulfide solid electrolyte membrane with the high-voltage positive electrode and the self-repairing ability of the sulfide solid electrolyte membrane.

[0061] In some embodiments, in step S1, the mass ratio of the sulfide particles to the binder is (80-99):(1-20). When the mass ratio of the sulfide particles to the binder is too high, it is not conducive to improving the mechanical properties of the sulfide solid electrolyte membrane. When the mass ratio of the sulfide particles to the binder is too low, it is not conducive to improving the ion transport performance of the sulfide solid electrolyte membrane.

[0062] In some embodiments, in step S1, the ball milling speed is greater than 2000 r / min and the time is greater than 1 hour. Meeting the above ball milling speed and ball milling time is more conducive to uniform mixing of sulfide particles and binder, thereby improving the performance of the sulfide solid electrolyte membrane. Optionally, the ball milling speed is 2000-10000 r / min, such as 2000 r / min, 3000 r / min, 4000 r / min, 5000 r / min, 6000 r / min, 7000 r / min, 8000 r / min, 9000 r / min, 10000 r / min, etc., and the time is 1-24 hours, such as 1 hour, 5 hours, 10 hours, 15 hours, 20 hours, 24 hours, etc., because when the ball milling speed is too high or the time is too long, the improvement of the above effects is not obvious, but is not conducive to cost reduction and efficiency improvement.

[0063] In some embodiments, in step S2, the pressure of the hot pressing treatment is greater than 100 MPa. Meeting the above pressure conditions helps improve the ion transport performance and mechanical properties of the sulfide solid electrolyte membrane. Optionally, the pressure of the hot pressing treatment is 100-1000 MPa, for example, 100 MPa, 200 MPa, 300 MPa, 400 MPa, 500 MPa, 600 MPa, 700 MPa, 800 MPa, 900 MPa, 1000 MPa, etc., because when the pressure of the hot pressing treatment is too high, the improvement of the above effects is not obvious, but is not conducive to cost reduction and efficiency improvement.

[0064] In addition, an embodiment of the present disclosure also provides an all-solid-state alkali metal ion battery, comprising the sulfide solid electrolyte membrane of the embodiment of the present disclosure, or the sulfide solid electrolyte membrane obtained by the preparation method of the embodiment of the present disclosure.

[0065] The all-solid-state alkali metal ion battery of the embodiment of the present disclosure can be an all-solid-state lithium ion battery, an all-solid-state sodium ion battery or an all-solid-state potassium ion battery, all of which have excellent cycle stability and rate performance.

[0066] The all-solid-state alkali metal ion battery of the embodiments of the present disclosure does not have a particular limitation on the positive electrode, and it can be any positive electrode in the related art, such as a high-voltage positive electrode or a high specific-capacity sulfur-selenium compound positive electrode. For example, the positive electrode active material of the high-voltage positive electrode may include lithium cobalt oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium cobalt manganese oxide, lithium-rich manganese-based material, nickel manganese spinel or Na x PR(CN)6 (where P and R are each independently selected from Fe, Co, Ni or Mn, and x is 1-2), sodium vanadium phosphate, sulfur, sodium iron sulfate, sodium ion fluorophosphate, sodium vanadium fluorophosphate, sodium iron fluorophosphate, sodium manganese oxide and sodium cobalt oxide, etc. At least one of them. The positive electrode active material of the high specific-capacity sulfur-selenium compound positive electrode may include elemental sulfur, elemental selenium, titanium disulfide, molybdenum disulfide, LiTi2(PS4)3, LiTi2(P(S x Se y )4)3 (x + y = 1), NaTi2(PS4)3 and NaTi2(P(S x Se y )4)3 (x + y = 1), etc. At least one of them.

[0067] The present disclosure will be described in detail below with reference to the embodiments and the drawings.

[0068] Example 1

[0069] An integrated sulfide solid electrolyte membrane based on a persulfide bond, which is composed of sulfide particles containing a polymer coating. The chemical composition of the sulfide particles containing a polymer coating is [Li8GeS6]3C 0.000221 O 0.000086 S 0.000157 H 0.000031 , where [Li8GeS6] is the sulfide particle, and C 0.000221 O 0.000086 S 0.000157 H 0.000031 is the polymer coating that forms a persulfide covalent bond with the surface of the sulfide particle.

[0070] The preparation method of the sulfide solid electrolyte membrane is specifically operated as follows:

[0071] S1. Under dry argon, the sulfide particles [Li8GeS6] and the binder A1 containing a terminal thiol and a persulfide bond structure ( x = 1000, y = 100) are mixed and ball-milled at a mass ratio of 99%:1%, the ball-milling speed is 2000 r / min, and the ball-milling time is 1 h to obtain a sulfide solid electrolyte powder.

[0072] The sulfide solid electrolyte powder is a sulfide particle containing a polymer coating, and the chemical composition of the sulfide particle containing the polymer coating is [Li8GeS6]3C 0.000221 O 0.000086 S 0.000157 H 0.000031 , consisting of sulfide particles [Li8GeS6] and a polymer coating C coated on the surface of the sulfide particles 0.000221 O 0.000086 S 0.000157 H 0.000031 composition.

[0073] S2. The sulfide solid electrolyte powder obtained in step S1 is hot-pressed at 100 MPa to obtain a sulfide solid electrolyte membrane with a thickness of 15 μm.

[0074] Application Example 1

[0075] An all-solid-state lithium-ion battery is a lithium nickel manganese oxide / Li all-solid-state battery assembled based on the sulfide solid electrolyte membrane of Example 1.

[0076] Example 2

[0077] An integrated sulfide solid electrolyte membrane based on persulfide bonds, comprising sulfide particles with a polymer coating, wherein the chemical composition of the sulfide particles with a polymer coating is [Li4SiS4] 38 C 0.0122 S 0.0003 H 0.0010 N 0.0047 , where [Li4SiS4] is sulfide particles, C 0.0122 S 0.0003 H 0.0010 N 0.0047 It is a polymer coating that forms a persulfur covalent bond with the surface of sulfide particles.

[0078] The preparation method of the sulfide solid electrolyte membrane is specifically performed as follows:

[0079] S1. Under dry argon, sulfide particles [Li4SiS4], a binder containing terminal thiol and persulfide bond structure A2 ( x=10, y=1000) were mixed and ball-milled in a mass ratio of 87.5%:12.5% ​​at a ball-milling speed of 2000 r / min for 20 h to obtain sulfide solid electrolyte powder.

[0080] The sulfide solid electrolyte powder is a sulfide particle containing a polymer coating, and the chemical composition of the sulfide particle containing a polymer coating is [Li4SiS4] 38 C 0.0122 S 0.0003 H0.0010 N 0.0047 , consisting of sulfide particles [Li4SiS4] and a polymer coating C coated on the surface of the sulfide particles 0.0122 S 0.0003 H 0.0010 N 0.0047 composition.

[0081] S2. The sulfide solid electrolyte powder obtained in step S1 is hot-pressed at 400 MPa to obtain a sulfide solid electrolyte membrane with a thickness of 20 μm.

[0082] Application Example 2

[0083] An all-solid-state lithium-ion battery, comprising a LiNi2O3 battery assembled with a sulfide solid electrolyte membrane according to Example 2. 0.8 Co 0.1 Mn 0.1 O2 / Li all-solid-state battery.

[0084] Example 3

[0085] An integrated sulfide solid electrolyte membrane based on persulfide bonds, comprising sulfide particles with a polymer coating, wherein the chemical composition of the sulfide particles with a polymer coating is [Li8SeS6] 24.5 C 0.0075 O 0.0027 S 0.0027 H 0.0006 N 0.0010 , where [Li8SeS6] is sulfide particles, C 0.0075 O 0.0027 S 0.0027 H 0.0006 N 0.0010 It is a polymer coating that forms a persulfur covalent bond with the surface of sulfide particles.

[0086] The preparation method of the sulfide solid electrolyte membrane is specifically performed as follows:

[0087] S1. In a dry argon atmosphere, sulfide particles [Li8SeS6], a binder containing terminal thiol and persulfide bond structure A3 ( x=100;y=100;z=100) were mixed and ball-milled in a mass ratio of 94.1%:5.9% at a ball-milling speed of 2000 r / min and a ball-milling time of 1 h to obtain sulfide solid electrolyte powder.

[0088] The sulfide solid electrolyte powder is a sulfide particle containing a polymer coating, and the chemical composition of the sulfide particle containing a polymer coating is [Li8SeS6] 24.5 C 0.0075 O 0.0027 S 0.0027H 0.0006 N 0.0010 , consisting of sulfide particles [Li8SeS6] and a polymer coating C coated on the surface of the sulfide particles 0.0075 O 0.0027 S 0.0027 H 0.0006 N 0.0010 composition.

[0089] S2. The sulfide solid electrolyte powder obtained in step S1 is hot-pressed at 1000 MPa to obtain a sulfide solid electrolyte membrane with a thickness of 22 μm.

[0090] Application Example 3

[0091] An all-solid-state lithium-ion battery is a LiCoO2 / Li all-solid-state battery assembled based on the sulfide solid electrolyte membrane of Example 3.

[0092] Example 4

[0093] An integrated sulfide solid electrolyte membrane based on persulfide bonds is composed of sulfide particles containing a polymer coating, and the chemical composition of the sulfide particles containing a polymer coating is [Li7SnS 5.5 ] 25.6 C 0.0017 O 0.0009 S 0.00063 H 0.00029 , among which, [Li7SnS 5.5 ] are sulfide particles, C 0.0017 O 0.0009 S 0.00063 H 0.00029 It is a polymer coating that forms a persulfur covalent bond with the surface of sulfide particles.

[0094] The preparation method of the sulfide solid electrolyte membrane is specifically performed as follows:

[0095] S1. Under dry argon, sulfide particles [Li7SnS 5.5 ], polymer binder A4 containing terminal thiol and persulfide bond structure ( x=200, y=100, z=1000) were mixed and ball-milled in a mass ratio of 95.5%:4.5% at a ball-milling speed of 2000 r / min for 18 h to obtain sulfide solid electrolyte powder.

[0096] The sulfide solid electrolyte powder is a sulfide particle containing a polymer coating, and the chemical composition of the sulfide particle containing the polymer coating is [Li7SnS 5.5 ] 25.6 C 0.0017 O 0.0009 S 0.00063 H0.00029 , composed of sulfide particles [Li7SnS 5.5 ] and polymer coating C coated on the surface of sulfide particles 0.0017 O 0.0009 S 0.00063 H 0.00029 composition.

[0097] S2. The sulfide solid electrolyte powder obtained in step S1 is hot-pressed at 600 MPa to obtain a sulfide solid electrolyte membrane with a thickness of 28 μm.

[0098] Application Example 4

[0099] An all-solid-state lithium-ion battery is a LiCoO2 / nano-Si all-solid-state battery assembled based on the sulfide solid electrolyte membrane of Example 4.

[0100] Example 5

[0101] An integrated sulfide solid electrolyte membrane based on persulfide bonds is composed of sulfide particles containing a polymer coating, and the chemical composition of the sulfide particles containing the polymer coating is [Li 3.4 Si 1.1 S 5.5 ] 71 C 0.016 O 0.0104 S 0.00011 H 0.002 N 2.5*10 -6 , among which [Li 3.4 Si 1.1 S 5.5 ] are sulfide particles, C 0.016 O 0.0104 S 0.00011 H 0.002 N 2.5*10 -6 It is a polymer coating that forms a persulfur covalent bond with the surface of sulfide particles.

[0102] The preparation method of the sulfide solid electrolyte membrane is specifically performed as follows:

[0103] S1. Under dry argon, sulfide particles [Li 3.4 Si 1.1 S 5.5 ], binder A5 containing terminal thiol and persulfide bond structure ( x=10, y=1000, z=500) were mixed and ball-milled in a mass ratio of 80%:20% at a ball-milling speed of 2000 r / min for 15 h to obtain sulfide solid electrolyte powder.

[0104] The sulfide solid electrolyte powder is a sulfide particle containing a polymer coating, and the chemical composition of the sulfide particle containing the polymer coating is [Li 3.4 Si 1.1 S 5.5 ] 71 C 0.016 O 0.0104 S 0.00011 H 0.002 N 2.5*10 -6 , composed of sulfide particles [Li 3.4 Si 1.1 S 5.5 ] and polymer coating C coated on the surface of sulfide particles 0.016 O 0.0104 S 0.00011 H 0.002 N 2.5*10 -6 composition.

[0105] S2. The sulfide solid electrolyte powder obtained in step S1 is hot-pressed at 500 MPa to obtain a sulfide solid electrolyte membrane with a thickness of 31 μm.

[0106] Application Example 5

[0107] An all-solid-state lithium-ion battery, comprising a LiNi2O3 battery assembled with a sulfide solid electrolyte membrane according to Example 5. 0.8 Co 0.1 Mn 0.1 O2 / nano-Si all-solid-state battery.

[0108] Example 6

[0109] An integrated sulfide solid electrolyte membrane based on persulfide bonds is composed of sulfide particles containing a polymer coating, and the chemical composition of the sulfide particles containing the polymer coating is [Li 7.6 SnS 5.8 ] 26 C 0.00064 O 0.00019 S 0.00038 H 0.000089 N 8.3*10 -7 Li 0.000039 , among which [Li 7.6 SnS 5.8 ] are sulfide particles, C 0.00064 O 0.00019 S 0.00038 H 0.000089 N 8.3*10 -7 Li 0.000039 It is a polymer coating that forms a persulfur covalent bond with the surface of sulfide particles.

[0110] The preparation method of the sulfide solid electrolyte membrane is specifically performed as follows:

[0111] S1. Under dry argon, sulfide particles [Li 7.6 SnS 5.8 ], polymer binder A6 containing terminal thiol and persulfide bond structure ( x=1000; y=10; z=10) were mixed and ball-milled in a mass ratio of 96.8%:3.2% at a ball-milling speed of 2000 r / min for 10 h to obtain sulfide solid electrolyte powder.

[0112] The sulfide solid electrolyte powder is a sulfide particle containing a polymer coating, and the chemical composition of the sulfide particle containing the polymer coating is [Li 7.6 SnS 5.8 ] 26 C 0.00064 O 0.00019 S 0.00038 H 0.000089 N 8.3*10 -7 Li 0.000039 , composed of sulfide particles [Li 7.6 SnS 5.8 ] and polymer coating C coated on the surface of sulfide particles 0.00064 O 0.00019 S 0.00038 H 0.000089 N 8.3*10 -7 Li 0.000039 composition.

[0113] S2. The sulfide solid electrolyte powder obtained in step S1 is hot-pressed at 300 MPa to obtain a sulfide solid electrolyte membrane with a thickness of 18 μm.

[0114] Application Example 6

[0115] An all-solid-state lithium-ion battery is a LiCoO2 / μm-Si all-solid-state battery assembled based on the sulfide solid electrolyte membrane of Example 6.

[0116] Example 7

[0117] An integrated sulfide solid electrolyte membrane based on persulfide bonds is composed of sulfide particles containing a polymer coating, and the chemical composition of the sulfide particles containing the polymer coating is [Na 7.6 SnS 5.8 ] 26 C 0.00064 O 0.00019 S 0.00038 H0.000089 N 8.3*10 -7 Na 0.000039 , where [Na 7.6 SnS 5.8 ] are sulfide particles, C 0.00064 O 0.00019 S 0.00038 H 0.000089 N 8.3*10 -7 Na 0.000039 It is a polymer coating that forms a persulfur covalent bond with the surface of sulfide particles.

[0118] The preparation method of the sulfide solid electrolyte membrane is specifically performed as follows:

[0119] S1. Under dry argon, sulfide particles [Na 7.6 SnS 5.8 ], polymer binder A7 containing terminal thiol and persulfide bond structure ( x=1000, y=10, z=10) were mixed and ball-milled in a mass ratio of 96.8%:3.2% at a ball-milling speed of 2000 r / min for 24 h to obtain sulfide solid electrolyte powder.

[0120] The sulfide solid electrolyte powder is a sulfide particle containing a polymer coating, and the chemical composition of the sulfide particle containing the polymer coating is [Na 7.6 SnS 5.8 ] 26 C 0.00064 O 0.00019 S 0.00038 H 0.000089 N 8.3*10 -7 Na 0.000039 , composed of sulfide particles [Na 7.6 SnS 5.8 ] and polymer coating C coated on the surface of sulfide particles 0.00064 O 0.00019 S 0.00038 H 0.000089 N 8.3*10 -7 Na 0.000039 composition.

[0121] S2. The sulfide solid electrolyte powder obtained in step S1 is hot-pressed at 300 MPa to obtain a sulfide solid electrolyte membrane with a thickness of 18 μm.

[0122] Application Example 7

[0123] An all-solid-state sodium ion battery, a NaCoO2 / μm-Si all-solid-state battery assembled based on the sulfide solid electrolyte membrane of Example 7.

[0124] Comparative Example 1

[0125] The preparation method of the sulfide solid electrolyte membrane of this comparative example is the same as that of Example 1, except that polytetrafluoroethylene (PTFE) is used as the binder.

[0126] Comparative Application Example 1

[0127] The all-solid-state lithium-ion battery and its preparation method of this comparative example are the same as the all-solid-state lithium-ion battery and its preparation method of Example 1, except that the solid electrolyte membrane used is the sulfide solid electrolyte membrane of Comparative Example 1.

[0128] Comparative Example 2

[0129] The preparation method of the sulfide solid electrolyte membrane of this comparative example is the same as that of Example 2, except that polytetrafluoroethylene (PTFE) is used as the binder.

[0130] Application Comparative Example 2

[0131] The all-solid-state lithium-ion battery and its preparation method of this comparative example are the same as the all-solid-state lithium-ion battery and its preparation method of Example 2, except that the solid electrolyte membrane used is the sulfide solid electrolyte membrane of Comparative Example 2.

[0132] Comparative Example 3

[0133] The preparation method of the sulfide solid electrolyte membrane of this comparative example is the same as that of Example 3, except that polytetrafluoroethylene (PTFE) is used as the binder.

[0134] Application Comparative Example 3

[0135] The all-solid-state lithium-ion battery and its preparation method of this application comparative example are the same as the all-solid-state lithium-ion battery and its preparation method of Example 3, except that the solid electrolyte membrane used is the sulfide solid electrolyte membrane of Comparative Example 3.

[0136] Comparative Example 4

[0137] The preparation method of the sulfide solid electrolyte membrane of this comparative example is the same as that of Example 4, except that polytetrafluoroethylene (PTFE) is used as the binder.

[0138] Comparative Application Example 4

[0139] The all-solid-state lithium-ion battery and its preparation method of this comparative example are the same as the all-solid-state lithium-ion battery and its preparation method of Example 4, except that the solid electrolyte membrane used is the sulfide solid electrolyte membrane of Comparative Example 4.

[0140] Comparative Example 5

[0141] The preparation method of the sulfide solid electrolyte membrane of this comparative example is the same as that of Example 5, except that polytetrafluoroethylene (PTFE) is used as the binder.

[0142] Application Comparative Example 5

[0143] The all-solid-state lithium-ion battery and its preparation method of this application comparative example are the same as the all-solid-state lithium-ion battery and its preparation method of Example 5, except that the solid electrolyte membrane used is the sulfide solid electrolyte membrane of Comparative Example 5.

[0144] Comparative Example 6

[0145] The preparation method of the sulfide solid electrolyte membrane of this comparative example is the same as that of Example 6, except that polytetrafluoroethylene (PTFE) is used as the binder.

[0146] Application Comparative Example 6

[0147] The all-solid-state lithium-ion battery and its preparation method of this application comparative example are the same as the all-solid-state lithium-ion battery and its preparation method of Example 6, except that the solid electrolyte membrane used is the sulfide solid electrolyte membrane of Comparative Example 6.

[0148] Comparative Example 7

[0149] The preparation method of the sulfide solid electrolyte membrane of this comparative example is the same as that of Example 7, except that polytetrafluoroethylene (PTFE) is used as the binder.

[0150] Application Comparative Example 7

[0151] The all-solid-state sodium ion battery and its preparation method of this application comparison example are the same as the all-solid-state sodium ion battery and its preparation method of Example 7, except that the solid electrolyte membrane used is the sulfide solid electrolyte membrane of Comparative Example 7.

[0152] Performance Test I: The physical and chemical properties of the solid sulfide electrolyte membranes of Examples 1-7 and the solid sulfide electrolyte membranes of Comparative Examples 1-7 were tested. The results are shown in Table 1.

[0153] (1) Thickness: The sulfide solid electrolyte membranes of Examples 1-7 and the sulfide solid electrolyte membranes of Comparative Examples 1-7 were placed on a thickness gauge and clamped. After the reading stabilized, the membrane thickness could be accurately measured. For each set of samples, the thickness of five different areas was repeatedly measured and the average value was calculated.

[0154] (2) Room temperature ionic conductivity: The electrochemical impedance spectra (EIS) of the sulfide solid electrolyte membranes of Examples 1-7 and the sulfide solid electrolyte membranes of Comparative Examples 1-7 were measured using a multi-channel electrochemical workstation (VMP-300). The sulfide solid electrolyte membranes were assembled into steel-to-steel symmetrical cells. The AC impedance spectrum was measured at a frequency range of 100 MHz to 7 MHz with a perturbation voltage of 10 mV. The corresponding impedance values ​​were read. The room temperature ionic conductivity was calculated according to the formula σ = L / RS, where L is the thickness of the sulfide solid electrolyte membrane in cm, R is the impedance of the sulfide solid electrolyte membrane in Ω, and S is the area of ​​the sulfide solid electrolyte membrane in cm. 2 .

[0155] (3) Oxidative decomposition voltage: The sulfide solid electrolyte membranes of Examples 1-7 and the sulfide solid electrolyte membranes of Comparative Examples 1-7 were subjected to linear sweep voltammetry (LSV) testing using a multi-channel electrochemical workstation (VMP-300). The relationship between current and voltage of the sulfide solid electrolyte membranes of Examples 1-7 and the sulfide solid electrolyte membranes of Comparative Examples 1-7 in the voltage range of 0-6.0 V was measured at a sweep rate of 1 mV / s. The voltage at which the sulfide solid electrolyte membranes began to oxidatively decompose was determined by analyzing the current-voltage curves.

[0156] (4) Tensile Strength: The sulfide solid electrolyte membranes of Examples 1-7 and the sulfide solid electrolyte membranes of Comparative Examples 1-7 were fabricated into uniform thin films 70 mm long, 10 mm wide, and 0.1 mm thick. The prepared films were placed on the fixture of a universal testing machine (MTS E43.104). A tensile force was applied to both ends of the specimen using a universal tensile testing machine to obtain stress-strain curves, and then tensile strength and elongation at break were obtained to evaluate the tensile properties of the sulfide solid electrolyte membranes.

[0157] Table 1. Chemical composition and physicochemical properties of solid sulfide electrolyte membranes of Examples 1-7

[0158] Table 2. Chemical composition and physicochemical properties of solid sulfide electrolyte membranes of Comparative Examples 1-7

[0159] From the comparison of Example 1 and Comparative Example 1, Example 2 and Comparative Example 2, Example 3 and Comparative Example 3, Example 4 and Comparative Example 4, Example 5 and Comparative Example 5, Example 6 and Comparative Example 6, and Example 7 and Comparative Example 7 in Tables 1 and 2, the room temperature ionic conductivity, oxidative decomposition voltage, and tensile strength of the solid sulfide electrolyte membranes of Examples 1-7 are significantly higher than those of the solid sulfide electrolyte membranes of Comparative Examples 1-7.

[0160] Performance Test II: The following test was conducted on the capacity retention rate of the all-solid-state batteries of Application Examples 1-7 and the all-solid-state batteries of Comparative Examples 1-7, and the results are as follows.

[0161] Comparison between Application Example 1 and Comparative Example 1: According to 0.1C rate, 2.7-5.1V (vs.Li + / Li) voltage range, the capacity retention rate of the lithium nickel manganese oxide / Li all-solid-state lithium ion battery of Example 1 after 800 cycles is 90%, while the capacity retention rate of the all-solid-state lithium ion battery of Comparative Example 1 is only 30%. The mechanism of improvement of battery cycle performance by using Example 1 is that: in the sulfide solid electrolyte membrane with PTFE as a binder of Comparative Example 1, there is only physical coating between PTFE and sulfide solid particles, and no covalent bond is formed. Therefore, the high voltage stability of the sulfide solid electrolyte membrane of Comparative Example 1 is poor, resulting in a low capacity retention rate of the all-solid-state lithium ion battery of Comparative Example 1. Compared with the sulfide solid electrolyte membrane with PTFE as a binder of Comparative Example 1, in Example 1, since the surface of the sulfide particles has SS bonds, the electron cloud density on S will increase significantly, which enhances the interaction force between S and Li. Under high voltage conditions, the strong interaction force between S and Li limits Li from a kinetic point of view. + from the electrolyte, limiting the S 2- oxidation, thereby improving the high-voltage stability of the sulfide solid electrolyte membrane and significantly improving the capacity retention rate of the all-solid-state lithium-ion battery of Application Example 1.

[0162] Comparison between Application Example 2 and Comparative Example 2: As shown in FIG2 , at a rate of 0.2C, 2.7-5.1V (vs. Li + / Li) voltage range, the charge and discharge test was carried out, and the LiNi 0.8 Co 0.1 Mn 0.1 The capacity retention rate of the O2 / Li all-solid-state lithium-ion battery after 100 cycles is 98%, while the capacity retention rate of the all-solid-state lithium-ion battery using comparative example 2 is only 80%. The mechanism of improvement of battery cycle performance by using embodiment 2 is that in the sulfide solid electrolyte membrane using PTFE as a binder in comparative example 2, PTFE and the sulfide solid particles are only physically coated, and no covalent bonds are formed. Therefore, the high-voltage stability of the sulfide solid electrolyte membrane in comparative example 2 is poor, resulting in a low capacity retention rate of the all-solid-state lithium-ion battery using comparative example 2. Compared with the sulfide solid electrolyte membrane using PTFE as a binder in comparative example 2, in embodiment 2, since the surface of the sulfide particles has SS bonds, the electron cloud density on S will increase significantly, thereby enhancing the interaction force between S and Li. Under high voltage conditions, the strong interaction force between S and Li limits Li from a kinetic point of view.+ from the electrolyte, limiting the S 2- oxidation, thereby improving the high voltage stability of the sulfide solid electrolyte and significantly improving the capacity retention rate of the all-solid-state lithium-ion battery of Application Example 2.

[0163] Comparison between Application Example 3 and Comparative Example 3: As shown in FIG3 , at a rate of 0.5C, 2.7-5.1V (vs. Li + / Li) voltage range, the charge and discharge test was carried out, and the capacity retention rate of the LiCoO2 / Li all-solid-state lithium ion battery using Example 3 after 100 cycles was 99%, while the capacity retention rate of the all-solid-state lithium ion battery using Comparative Example 3 was only 74%. The mechanism of improvement of battery cycle performance by using Example 3 is that in the sulfide solid electrolyte membrane using PTFE as a binder in Comparative Example 3, PTFE and the sulfide solid particles are only physically coated, and no covalent bond is formed. Therefore, the high voltage stability of the sulfide solid electrolyte membrane in Comparative Example 3 is poor, resulting in a low capacity retention rate of the all-solid-state lithium ion battery using Comparative Example 3. Compared with the sulfide solid electrolyte membrane using PTFE as a binder in Comparative Example 3, in Example 3, since the surface of the sulfide particles has SS bonds, the electron cloud density on S will increase significantly, thereby enhancing the interaction force between S and Li. Under high voltage conditions, the strong interaction force between S and Li limits Li from a kinetic point of view. + from the electrolyte, limiting the S 2- oxidation, thereby improving the high voltage stability of the sulfide solid electrolyte and significantly improving the capacity retention rate of the all-solid-state lithium-ion battery of Application Example 3.

[0164] Comparison of Application Example 4 and Comparative Example 4: According to 0.1C rate, 2.7-5.1V (vs.Li + / Li) voltage range, the charge and discharge test was carried out, and the capacity retention rate of the LiCoO2 / nano-Si all-solid-state lithium ion battery using Example 4 after 300 cycles was 96%, while the capacity retention rate of the all-solid-state lithium ion battery using Comparative Example 4 was only 51%. The mechanism of improvement of battery cycle performance by using Example 4 is that in the sulfide solid electrolyte membrane with PTFE as a binder in Comparative Example 4, PTFE and the sulfide solid particles are only physically coated, and no covalent bonds are formed. Therefore, the high voltage stability of the sulfide solid electrolyte membrane in Comparative Example 4 is poor, resulting in a low capacity retention rate of the all-solid-state lithium ion battery using Comparative Example 4. Compared with the sulfide solid electrolyte membrane with PTFE as a binder in Comparative Example 4, in Example 4, since the surface of the sulfide particles has SS bonds, the electron cloud density on S will increase significantly, which enhances the interaction force between S and Li. Under high voltage conditions, the strong interaction force between S and Li limits Li from a kinetic point of view.+ from the electrolyte, limiting the S 2- oxidation, thereby improving the high-voltage stability of the sulfide solid electrolyte and significantly improving the capacity retention rate of the all-solid-state lithium-ion battery of Application Example 4.

[0165] Comparison between Application Example 5 and Comparative Example 5: As shown in FIG4 , at a rate of 0.1C, 2.7-5.1V (vs. Li + / Li) voltage range, using the LiNi of Application Example 5 0.8 Co 0.1 Mn 0.1 The capacity retention rate of the O2 / nano-Si all-solid-state battery after 100 cycles is 97%, while the capacity retention rate of the all-solid-state lithium-ion battery using comparative example 5 is only 65%. The mechanism of improvement of battery cycle performance by using embodiment 5 is that in the sulfide solid electrolyte membrane using PTFE as a binder in comparative example 5, PTFE and the sulfide solid particles are only physically coated, and no covalent bonds are formed. Therefore, the high-voltage stability of the sulfide solid electrolyte membrane in comparative example 5 is poor, resulting in a low capacity retention rate of the all-solid-state lithium-ion battery using comparative example 5. Compared with the sulfide solid electrolyte membrane using PTFE as a binder in comparative example 5, in embodiment 5, since the surface of the sulfide particles has SS bonds, the electron cloud density on S will increase significantly, thereby enhancing the interaction force between S and Li. Under high voltage conditions, the strong interaction force between S and Li limits Li from a kinetic point of view. + from the electrolyte, limiting the S 2- oxidation, thereby improving the high-voltage stability of the sulfide solid electrolyte and significantly improving the capacity retention rate of the all-solid-state lithium-ion battery of Application Example 5.

[0166] Comparison between Application Example 6 and Comparative Example 6: As shown in FIG5 , at a rate of 0.1C, 2.7-5.1V (vs. Li + / Li) voltage range, the charge and discharge test was carried out, and the capacity retention rate of the LiCoO2 / μm-Si all-solid-state lithium ion battery using Example 6 after 100 cycles was 94%, while the capacity retention rate of the all-solid-state lithium ion battery using Comparative Example 6 was only 75%. The mechanism of improvement of battery cycle performance by using Example 6 is that in the sulfide solid electrolyte membrane with PTFE as a binder in Comparative Example 6, PTFE and the sulfide solid particles are only physically coated, and no covalent bonds are formed. Therefore, the high voltage stability of the sulfide solid electrolyte membrane in Comparative Example 6 is poor, resulting in a low capacity retention rate of the all-solid-state lithium ion battery using Comparative Example 6. Compared with the sulfide solid electrolyte membrane with PTFE as a binder in Comparative Example 6, in Example 6, due to the SS bond on the surface of the sulfide particles, the electron cloud density on S will increase significantly, which enhances the interaction force between S and Li. Under high voltage conditions, the strong interaction force between S and Li limits Li from a kinetic point of view. + from the electrolyte, limiting the S 2- oxidation, thereby improving the high-voltage stability of the sulfide solid electrolyte and significantly improving the capacity retention rate of the all-solid-state lithium-ion battery of Application Example 6.

[0167] Comparison of Application Example 7 and Comparative Example 7: According to 0.1C rate, 2.0-4.1V (vs. Na / Na + ) voltage range, the charge and discharge test was carried out, and the capacity retention rate of the NaCoO2 / μm-Si all-solid-state battery using Example 7 after 50 cycles was 90%, while the capacity retention rate of the all-solid-state sodium ion battery using Comparative Example 7 was only 70%. The mechanism of improvement of battery cycle performance by using Example 7 is that in the sulfide solid electrolyte membrane using PTFE as a binder in Comparative Example 7, there is only physical coating between PTFE and the sulfide solid particles, and no covalent bond is formed. Therefore, the high voltage stability of the sulfide solid electrolyte membrane in Comparative Example 7 is poor, resulting in a low capacity retention rate of the all-solid-state lithium ion battery using Comparative Example 7. Compared with the sulfide solid electrolyte membrane using PTFE as a binder in Comparative Example 7, in Example 7, since the surface of the sulfide particles has SS bonds, the electron cloud density on S will increase significantly, thereby enhancing the interaction between S and Na. Under high voltage conditions, the strong interaction between S and Li limits Na from a kinetic point of view. + from the electrolyte, limiting the S 2- oxidation, thereby improving the high-voltage stability of the sulfide solid electrolyte and significantly improving the capacity retention rate of the all-solid-state lithium-ion battery of Application Example 7.

[0168] In the present disclosure, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0169] Although the embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are illustrative and are not to be construed as limitations on the present disclosure. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present disclosure.

Claims

1. A sulfide solid electrolyte membrane, composed of sulfide particles containing a polymer coating, the chemical composition of the sulfide particles containing a polymer coating being [E m M n S o C α O β S γ H δ N ζ E a ; wherein, [E m M n S o is a sulfide particle, E is selected from Li + or Na + , M is selected from Si 4+ , Ge 4+ , Se 4+ or Sn 4+ , and 3 ≤ m ≤ 8, 1 ≤ n ≤ 2, 2 ≤ o ≤ 8; C α O β S γ H δ N ζ E a is a polymer coating that forms a persulfide bond with the surface of the sulfide particle, and α is selected from 0.0001 - 1, β is selected from 0 - 0.5, γ is selected from 0.000001 - 1, δ is selected from 0.00001 - 2, ζ is selected from 0 - 0.01, and a is selected from 0 - 0.0001.

2. The sulfide solid electrolyte film according to claim 1, wherein Based on the total mass of the sulfide solid electrolyte membrane being 100%, the mass fraction of the sulfide particles is 80 - 99%, and the mass fraction of the polymer coating is 1 - 20%.

3. The sulfide solid electrolyte film according to claim 1 or 2, wherein The thickness of the sulfide solid electrolyte membrane is 15 - 35 μm.

4. The method for preparing a sulfide solid electrolyte membrane according to any one of claims 1-3, wherein, Comprising the following steps: S1. Mix the sulfide particles and the binder and perform ball milling in a dry atmosphere to obtain the sulfide particles containing the polymer coating; The binder is a polymer containing terminal thiol and persulfide bond structures; S2. Perform hot pressing on the sulfide particles containing the polymer coating to obtain the sulfide solid electrolyte membrane.

5. The preparation method of the sulfide solid electrolyte membrane according to claim 4, wherein, In step S1, the structural general formula of the binder is formula (1): Wherein, x is selected from 10 - 1000, and y and z are each independently selected from 0 - 2000; A and C are each independently selected from H, Cl, CN or methyl; B and D are each independently selected from an alkoxycarbonyl group having 10 or fewer carbon atoms, a cyano group, a carbamoyl group, a group containing a terminal carboxylate structure having 10 or fewer carbon atoms, a group represented by formula (2), a group represented by formula (3), or a group represented by formula (4), where in formula (2) and formula (3), w is each independently selected from 0 to 100; R is selected from an alkyl group with less than ten carbons containing a terminal mercapto group, a terminal hydroxyl group, a terminal methanesulfonyl group, a terminal cyano group, a terminal alkoxyphosphoryl group, a terminal carboxylic acid or a terminal carboxylic acid derivative group.

6. The method for preparing a sulfide solid electrolyte membrane according to claim 4, wherein, In step S1, the mass ratio of the sulfide particles to the binder is (80 - 99):(1 - 20).

7. The method for preparing a sulfide solid electrolyte membrane according to claim 4, wherein, In step S1, the speed of the ball milling treatment is above 2000 r / min, and the time is above 1 h.

8. The method for preparing a sulfide solid electrolyte film according to claim 7, wherein, In step S1, the speed of the ball milling treatment is 2000 - 10000 r / min, and the time is 1 - 24 h.

9. The method for preparing a sulfide solid electrolyte film according to claim 4, wherein, In step S2, the pressure of the hot pressing treatment is above 100 MPa.

10. A all-solid-state alkali metal ion battery, characterized in that, Comprising the sulfide solid electrolyte membrane according to any one of claims 1 - 3, or the sulfide solid electrolyte membrane obtained by the preparation method according to any one of claims 4 - 9.

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