O / F synergistically doped Li-Y-Zr-Cl-S sulfide solid electrolyte material as well as preparation method and application of O / F synergistically doped Li-Y-Zr-Cl-S sulfide solid electrolyte material

Abstract

The invention discloses an O / F synergistically doped Li-Y-Zr-Cl-S sulfide solid electrolyte material and a preparation method and application thereof, and belongs to the technical field of lithium ion batteries, and the chemical general formula is Lia (YxZr1-x) bClc-yFySd-zOz. Through O / F synergistic doping and Y and Zr cation co-doping, the air stability and electrode interface compatibility are remarkably improved while 10S / cm magnitude room temperature ionic conductivity is maintained, HS generation and lithium dendrite growth are inhibited, and the material can adapt to a high-voltage positive electrode environment of 4.5 V or below. The preparation method adopts a solid-phase synthesis process, comprises the steps of raw material preparation, ball-milling mixing, heat treatment, powder treatment and forming, is simple in process and relatively low in cost, and does not need extreme anhydrous and anaerobic conditions. The electrolyte material can be used for a high-voltage all-solid-state lithium battery, a modular integrated battery system and the like, the cycle life of the battery is greatly prolonged, the safety performance of the battery is greatly improved, and the electrolyte material has wide commercial application prospects.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery technology, and in particular to a Li-Y-Zr-Cl-S sulfide solid electrolyte material with O / F synergistic doping, its preparation method and application. Background Technology

[0002] All-solid-state lithium batteries, by using solid electrolytes instead of flammable organic liquid electrolytes, have enormous potential to improve battery safety and energy density. Among them, sulfide-based solid electrolyte materials, with their high ionic conductivity of 10⁻³~10⁻²S / cm at room temperature, as well as good interfacial contact and processing performance, have become one of the most commercially promising solid electrolytes.

[0003] However, existing sulfide solid electrolytes have significant drawbacks: First, they have extremely poor air stability. When exposed to air, especially in a moisture-containing environment, they rapidly decompose to generate toxic hydrogen sulfide (H2S) gas, leading to material structure damage and ion conductivity degradation. Second, they have insufficient electrode / electrolyte interface stability and a narrow electrochemical stability window. They are prone to side reactions with high-voltage cathodes (such as nickel-rich layered oxide cathodes) and lithium metal anodes, causing problems such as lithium dendrite growth, increased interface impedance, and mechanical failure, which severely restricts their application in high-energy-density all-solid-state batteries.

[0004] To address these issues, researchers have proposed strategies such as surface coating protection, electrode material doping modification, and electrolyte composition regulation. Among these, anion or cation doping is an effective approach: fluorine doping (using LiF as a dopant source) can generate a LiF-rich passivation layer in situ at the electrolyte-lithium metal interface, suppressing side reactions and expanding the electrochemical stability window. However, single fluorine doping has limited improvement on the bulk air stability of the material, and excessive doping can lead to lattice shrinkage and decreased ionic conductivity. Oxygen doping (in oxide form) can reduce H2S generation and increase lattice energy through the mixed anion effect, but single oxygen doping may also reduce ionic conductivity. Therefore, relying solely on single doping is insufficient to simultaneously achieve air stability, interfacial stability, and high ionic conductivity; new synergistic doping strategies are urgently needed to optimize material performance. Summary of the Invention

[0005] This invention aims to provide a Li-Y-Zr-Cl-S sulfide solid electrolyte material with O / F co-doping, solving the problems of poor air stability and insufficient interfacial compatibility of existing sulfide electrolytes, while maintaining high ionic conductivity. By constructing a stable and highly mobile crystal structure, harmful reactions are suppressed, thereby improving the overall performance and lifespan of all-solid-state batteries. The contents of this invention are as follows:

[0006] The first object of the present invention is to provide a Li-Y-Zr-Cl-S-based sulfide solid electrolyte material containing O / F co-doping. The technical point is that its chemical general formula is: Li a (Y x Zr 1-x ) b Cl  c-y F y S  d-z O z , where: 0 < x < 1, the value range of a is 5 to 10, the value range of b is 0.5 to 2, the value range of c is 1 to 3, the value range of d is 4 to 12, y / c is 0.05 to 0.5, and z / d is 0.01 to 0.2.

[0007] The second object of the present invention is to provide a preparation method of the above solid electrolyte material. The technical point is that it includes the following steps:

[0008] Step 1, raw material preparation: Under the protection of an inert atmosphere, weigh raw materials of Li2S, LiCl, LiF, Li2O, YCl3, and ZrCl4 according to the stoichiometric ratio of the target chemical general formula;

[0009] Step 2, ball milling and mixing: Under the protection of an inert gas, ball mill the raw material mixture at a speed of 300 - 500 rpm for 10 - 30 hours to obtain a precursor powder;

[0010] Step 3, heat treatment reaction: Under the protection of an inert atmosphere, keep the precursor powder at 200 - 500 °C for 2 - 5 hours, and naturally cool it to room temperature;

[0011] Step 4, powder treatment: Grind and screen in an inert atmosphere to obtain electrolyte powder; optionally, perform short-time sintering at about 500 °C.

[0012] The third object of the present invention is to provide an application of the above solid electrolyte material in a all-solid-state lithium battery. The technical point is that the all-solid-state lithium battery includes a high-voltage positive electrode, a metallic lithium or lithium-free negative electrode, and an electrolyte diaphragm made of the electrolyte material.

[0013] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0014] 1. High ionic conductivity and stable structure: The room-temperature ionic conductivity can reach the order of 10⁻³ S / cm, approaching the level of undoped sulfides. At the same time, the crystal lattice is dense and stable, and it is not easy to undergo phase transformation or decomposition;

[0015] 2. Good interface compatibility: When in contact with a lithium metal anode, it forms a stable LiF enrichment layer, suppressing lithium dendrite growth; when in contact with a high-voltage cathode (such as NMC811), it suppresses the formation of space charge layer and by-products, and can adapt to cathode potential environments up to 4.5V, thus broadening the application range of cathode materials.

[0016] 3. Significantly improved air stability: When placed in dry air with a dew point of -40°C for a long time, the weight gain is less than 1% and the H2S generation is less than 1ppm. It can be prepared and assembled without extreme anhydrous and oxygen-free conditions, reducing manufacturing costs.

[0017] 4. Excellent overall electrochemical performance: After 500 cycles at 0.5C rate, the all-solid-state battery using this electrolyte retains more than 85% of its capacity and maintains a coulombic efficiency of more than 99%, with significantly improved cycle stability.

[0018] Instruction manual illustrations

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is an XRD test image. Detailed Implementation

[0021] The present invention provides a Li-Y-Zr-Cl-S sulfide solid electrolyte material with O / F co-doping, the chemical formula of which is: Li a (Y x Zr 1-x ) b Cl c-y F y S d-z O z The elements are defined as follows: Li for lithium, Y for yttrium, Zr for zirconium, Cl for chlorine, F for fluorine, S for sulfur, and O for oxygen. The definitions and value ranges of each parameter are as follows:

[0022] Parameter a: The atomic number or effective stoichiometric ratio of lithium element, with a value range of 5 to 10; those skilled in the art can determine the appropriate Li content to achieve overall electrical neutrality through charge conservation according to the doping levels of Y and Zr and the substitution levels of O and F. When some high-valent cations (such as P^5+) are replaced by lower-valent Y^3+ and Zr^4+, the Li content usually needs to be increased to compensate for the lack of positive charge, so the materials of the present invention tend to be lithium-rich compositions. Sufficient lithium content is beneficial to providing more carriers, thus maintaining high ionic conductivity.

[0023] Parameter b: The total atomic number stoichiometric ratio of (Y + Zr), with a value range of 0.5 to 2; when referring to the structure of the typical sulfide electrolyte Li6PS5Cl, each unit cell contains 1 P atom; in the materials of the present invention, approximately 1 (Y + Zr) equivalent atom can be correspondingly included. Therefore, in one embodiment, b = 1 (for example, Y 0.5 Zr 0.5 represents that each unit cell contains 0.5 Y and 0.5 Zr, that is, every two unit cells contain 1 Y and 1 Zr). Of course, by appropriately enlarging the unit cell model or in the case of non-stoichiometric compounds, b can also take other effective values.

[0024] Parameter c: The base stoichiometric ratio of Cl element, with a value range of 1 to 3;

[0025] Parameter d: The base stoichiometric ratio of S element, with a value range of 4 to 12;

[0026] The above two parameters correspond to the approximate quantity ratio of halogen and sulfur elements in the material. Sulfide electrolytes containing halogen often have a structure similar to argyrodite, such as c = 1 and d = 5 in Li6PS5Cl. In the materials of the present invention, due to the change of some cation valences and anion doping, the total number of anions actually required may be adjusted, but overall, S is the main anion and Cl is the minor anion. It is preferred to select c and d to make the material form a stable crystal structure, such as a cubic crystal phase similar to the Li6PS5Cl structure type

[0027] Parameter x: The mole fraction of Y and Zr, 0 < x < 1, preferably x:(1 - x) is 0.1:0.9 to 0.9:0.1, more preferably 0.5:0.5 to simultaneously exert the synergistic effect of the two doping cations;

[0028] Parameter y: The doping mole number of F relative to Cl, y / c (the mole fraction of fluorine substituting chlorine) is 0.05 to 0.5, preferably 0.1 to 0.3;

[0029] Parameter z: The doping mole number of O relative to S, z / d (the mole fraction of oxygen substituting sulfur) is 0.01 to 0.2, preferably 0.05 to 0.1.

[0030] The doping amounts y and z are small positive values, meaning that a small amount of fluorine and oxygen doping can achieve a synergistic effect. Preferably, y / c (the molar fraction of fluorine replacing chlorine) is in the range of 0.05 to 0.5, more preferably about 0.1 to 0.3; z / d (the molar fraction of oxygen replacing sulfur) is in the range of 0.01 to 0.2, more preferably about 0.05 to 0.1. That is, the material performance is optimal when chlorine sites are replaced by 5% to 50% fluorine and sulfur sites are replaced by 1% to 20% oxygen. Although excessively high doping amounts can further improve stability, they may significantly reduce ionic conductivity, which is not conducive to the overall performance balance. Therefore, moderate doping amounts are preferable.

[0031] In the above materials, Y³⁺ and Zr 4 ⁺ Together, they replace high-valence cation sites (such as primary phosphorus sites) in sulfide crystals, adjusting the lattice charge balance and forming lithium ion vacancies; Y and Zr, as doping cations, jointly occupy cation sites in the lattice, allowing for fine-tuning of the material's crystal phase structure and defect concentration: Y 3+ The introduction of [something] helps to improve Li + The occupancy concentration of Zr, while Zr 4+ It helps to improve the rigidity and stability of the structure, and the combination of the two can achieve better electrical conductivity and mechanical strength.

[0032] O partially replaces sulfur to form a SO mixed anionic framework. This framework has higher bond energy, making the material more stable in air and less prone to violent reactions with water, thus effectively suppressing the formation of volatile byproducts such as H2S. At the same time, the mixed anionic structure increases the disorder of lattice positions and the continuous path of lithium ion migration, which helps to maintain high ionic conductivity.

[0033] The partial substitution of chlorine with fluorine (F) to form an S-Cl-F multi-anion coexistence structure is beneficial for the hopping migration of lithium ions between anion sites (similar to the reported effect of borate / halogen co-doping on improving ionic conductivity). On the other hand, fluorine doping enables the material to generate a LiF-rich interface layer in situ when in contact with metallic lithium. The high stability of LiF effectively prevents further side reactions. The three factors work synergistically to improve performance.

[0034] This invention also provides a method for preparing the above-mentioned electrolyte material, which employs a solid-phase synthesis process and includes the following steps:

[0035] Raw material preparation: Under an inert atmosphere, weigh the raw materials according to the stoichiometric ratio of the target chemical formula. The raw materials include lithium sulfide (Li2S), lithium chloride (LiCl), lithium fluoride (LiF), lithium oxide (Li2O), yttrium chloride (YCl3), and zirconium chloride (ZrCl4). The purity of the raw materials must meet the requirements of solid-phase synthesis.

[0036] Ball milling: The raw material mixture is placed in the sealed grinding jar of a high-energy ball mill and ball milled at 300~500 rpm for 10~30 hours under inert gas protection to form a uniform precursor powder;

[0037] Heat treatment reaction: The precursor powder is transferred to a sealed container under an inert atmosphere and kept at 200~500℃ for 2~5 hours for solid-phase reaction and crystallization, and then naturally cooled to room temperature.

[0038] Powder processing: The cooled product is taken out in an inert atmosphere, ground and sieved to obtain electrolyte powder with uniform particle size; optionally, a second stage of heat treatment (short-time sintering at about 500℃) is performed to improve crystallinity;

[0039] Molding and Application: Electrolyte powder is cold-pressed into electrolyte discs under a pressure of 200~500MPa, or electrolyte membranes are prepared by coating process for use in all-solid-state battery assembly.

[0040] The O / F co-doped Li-Y-Zr-Cl-S sulfide solid electrolyte material of this invention can be prepared through the above process steps. This method has a simple process flow, is highly operable, and is suitable for mass production. The combination of ball milling and low-temperature solid-state synthesis reduces the material preparation cost; avoiding high-temperature sintering also reduces the risk of oxygen-doped material decomposition, ensuring consistent product performance.

[0041] The O / F co-doped Li-Y-Zr-Cl-S sulfide solid electrolyte material of the present invention has broad application prospects in the field of new energy batteries, and is particularly suitable for the following aspects:

[0042] High-voltage all-solid-state lithium battery: The electrolyte material of this invention has a wide electrochemical stability window and excellent interfacial stability, and can be stably used with high-voltage cathodes (such as NMC811, nickel-rich lithium cobalt oxide, and other 4V-level cathode materials) and lithium metal or lithium-free anodes to construct high-energy-density all-solid-state batteries. Utilizing its high ionic conductivity and stable interface, the electrolyte of this invention can support high-rate charge-discharge and long cycle life, thereby meeting the stringent requirements of electric vehicle power batteries for energy density and lifespan.

[0043] Air Exposure Process Compatibility: Traditional sulfide electrolytes are extremely sensitive to the environment, requiring the preparation and assembly of batteries in a strictly anhydrous and oxygen-free inert atmosphere, which significantly increases manufacturing costs. The electrolyte material of this invention exhibits significantly improved stability in dry air, allowing for powder transfer, electrolyte sheet fabrication, and battery stacking assembly processes in dry room environments (such as cleanrooms with a dew point of approximately -40°C) without the need for continuous glove box protection. This compatibility with the process environment simplifies the production process of all-solid-state batteries, facilitating large-scale manufacturing.

[0044] Modular Integrated Battery System: The electrolyte material of this invention can be fabricated into large-area, electrode-electrolyte integrated solid-state battery cells, supporting modular integration of multiple cells. Due to the high stability of the material, the electrolyte sheet can be exposed for extended periods during battery module integration while maintaining performance, making it suitable for the manufacture of stacked batteries, pouch solid-state batteries, and solid-state battery modules / packs. Its mechanical properties and stable interface prevent interface debonding or performance degradation during battery cell integration, improving system reliability and safety.

[0045] Other related fields: In addition to its use in power batteries and energy storage batteries, the solid electrolyte material of this invention can also be applied to novel energy storage devices and electrochemical systems, such as all-solid-state lithium-air batteries, all-solid-state lithium-sulfur batteries, and ion conductor applications requiring both high ionic conductivity and environmental stability. The O / F co-doping strategy in the material also provides valuable insights for the development of other types of ion conductor materials, and can promote the application of solid-state ionic materials in sensors, thin-film batteries, and other fields.

[0046] In summary, the oxygen / fluorine co-doped Li-Y-Zr-Cl-S sulfide solid electrolyte material provided by this invention achieves a balance between high ionic conductivity, excellent interfacial stability, and air stability, significantly overcoming the shortcomings of traditional sulfide electrolytes. It can meet the stringent requirements of next-generation high-safety, high-energy-density all-solid-state lithium batteries for electrolyte materials, and has extremely high practical value and application potential.

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0048] (a) Sample preparation

[0049] 1. Preparation of Sample A (O / F co-doped)

[0050] According to the general chemical formula Li9(Y0.5Zr0.5)Cl1.8F0.2S 10 ₋zOz (z≈0.5) Weigh the raw materials: Li2S, LiCl, LiF, Li2O, YCl2, ZrCl4, where the molar ratio of Y to Zr is 1:1, the molar fraction of oxygen doping is 5%, and the molar fraction of fluorine doping is 10%.

[0051] After mixing the raw materials in an Ar gas glove box, the mixture was sealed and ball-milled at 400 rpm for 20 hours. The precursor powder obtained from the ball milling was placed in a sealed quartz tube filled with N2 and kept at 300°C for 4 hours. After cooling, sample A electrolyte powder was obtained.

[0052] 2. Preparation of Sample B (F-doped only, control)

[0053] Except for the absence of Li₂O, the formulation and preparation process are identical to those of sample A, with the general chemical formula Li₉(Y). 0.5 Zr 0.5 )Cl 1.8 F 0.2 S 10 This is used to compare and verify the effect of synergistic doping.

[0054] (II) Performance Characterization and Testing

[0055] 1. Crystal structure analysis

[0056] X-ray diffraction (XRD) was used to test sample A. The sample A mainly showed a cubic crystal phase with no obvious impurity peaks. The diffraction peak shifted to the right by 29.3° compared to the undoped control sample, and the cell volume shrank by about 0.5%, which proved that O / F doping entered the lattice and improved the structural compactness. The diffraction peak of sample B shifted slightly to a lower angle, and the lattice parameters were greater than those of sample A.

[0057] 2. Ionic conductivity test

[0058] Impedance spectroscopy (EIS) was used to press the samples into circular discs with a diameter of 10 mm and a thickness of 1 mm, with stainless steel electrodes plated on both sides for testing. Sample A had a room temperature ionic conductivity of 2.0 × 10⁻³ S / cm and an ion migration activation energy of 0.34 eV; Sample B had a room temperature ionic conductivity of 2.3 × 10⁻³ S / cm and an activation energy of 0.28–0.30 eV. Sample A maintained high ionic conductivity while improving structural stability.

[0059] 3. Electrochemical Cyclic Performance Testing

[0060] Assemble the all-solid-state battery: The positive electrode is NMC811 coated aluminum foil, the negative electrode is copper foil (lithium-free negative electrode), and the electrolyte is a 300μm thick sample A or B cold-pressed sheet. After activation at 0.1C for 2 cycles at room temperature, a 0.5C rate cycle test is performed.

[0061] Sample A battery has an initial discharge specific capacity of approximately 160 mAh / g, and after 500 cycles, its capacity retention rate is higher than 85%, with a coulombic efficiency of ≥99%.

[0062] After 500 cycles, the capacity retention rate of sample B battery was less than 65%, a by-product layer appeared at the positive electrode interface, and lithium dendrite growth was more obvious on the negative electrode side.

[0063] 4. Air stability test

[0064] Expose the sample to dry air with a dew point of -40°C:

[0065] After 72 hours of exposure, sample A showed no significant changes in appearance, gained less than 1% in weight, and maintained an H2S concentration consistently below 1 ppm.

[0066] After 12 hours of exposure, sample B showed an H2S concentration exceeding 5 ppm, and the powder exhibited clumping and increased mass.

[0067] (III) Conclusion of the Implementation Examples

[0068] XRD detection, such as Figure 1 Sample A, as shown, primarily exhibits a cubic phase diffraction pattern with no obvious impurity peaks, indicating that O and F doping has entered the material's crystal lattice. XRD analysis of the electrolyte powder from Sample A, after being pressed into a pellet, revealed a slight rightward shift in its diffraction peak positions compared to Sample B (towards a higher 2θ angle). For example, the original main peak at approximately 29° (corresponding to the diffraction of the matrix crystal plane) shifts to approximately 29.3° in Sample A. This increase in diffraction peak angle indicates the incorporation of O with a smaller radius and higher electronegativity. 2- F - The decrease in cell parameters indicates a slight lattice contraction. This lattice contraction reflects an increase in lattice energy and a denser structure, contributing to improved thermodynamic stability. The change in cell parameters can be estimated by calculating peak shifts using the Bragg formula. The results show that the cell volume of sample A shrank by approximately 0.5% compared to the undoped control, demonstrating that O / F co-doping effectively alters the crystal structure. Analysis indicates that sample B exhibits similar main diffraction peak positions to sample A, but is slightly shifted at a lower angle relative to sample A, indicating a slight increase in lattice parameters (compared to sample A) in the absence of oxygen doping.

[0069] Ionic conductivity tests show that sample A has an ionic conductivity of approximately 2.0 × 10⁻⁶ at 25°C. −3 The ion migration activation energy of sample A is approximately 0.34 eV, and the ionic conductivity of sample B at 25 °C is approximately 2.3 × 10⁻⁶ S / cm. −3 The S / cm is about 15% higher than that of sample A; its ion migration activation energy is about 0.28~0.30 eV, slightly lower than that of sample A. This indicates that fluorine doping has little effect on ion conduction performance or even a slight improvement. However, as mentioned above, the air stability and interfacial stability of the material are insufficient when oxygen synergy is lacking. This suggests that while O / F synergistic doping brings structural stability, it also slightly increases the ion migration barrier.

[0070] Electrochemical cycling tests showed that the initial discharge specific capacity of the battery using electrolyte A was approximately 160 mAh / g (based on the mass of the positive electrode active material), and the capacity retention rate remained above 85% after 500 cycles. In contrast, the control battery using only fluorine-doped electrolyte B had a capacity retention rate of less than 70% after 500 cycles under the same conditions. The coulombic efficiency of battery A remained above 99% throughout the long cycling process, with no significant decrease in voltage plateau. This indicates that the co-doped electrolyte of this invention effectively suppresses capacity decay during cycling, significantly improving cycle life and stability. The NMC811 lithium-free anode all-solid-state battery using electrolyte B had an initial discharge capacity comparable to that of sample A, but its capacity began to decay rapidly after approximately 200 cycles, and the capacity retention rate dropped to approximately 65% ​​after 500 cycles.

[0071] Interface analysis showed that the appearance and color of sample A powder remained essentially unchanged, with a weight gain of less than 1%. During exposure, the H2S concentration in the environment was continuously monitored using a gas sensor, and the results showed that the H2S content remained below 1 ppm throughout the entire 72-hour exposure, which was negligible. In contrast, for the control sample B powder, after only 12 hours of exposure in the same environment, H2S gas exceeding 5 ppm was detected in the container, accompanied by slight agglomeration and a gradual increase in powder weight. Clearly, sample A's tolerance to moisture is far superior to traditional sulfide electrolytes, and it is less prone to hydrolysis and decomposition in air. This characteristic will greatly simplify the storage, processing, and battery assembly of the electrolyte, which is of great significance for practical applications. A significant byproduct layer, possibly sulfate or lithium sulfate, appeared at the positive electrode interface of sample B battery, leading to increased interfacial impedance. On the negative electrode side, due to the presence of only a LiF interfacial layer and the lack of oxygen doping for inhibition, the growth of lithium dendrites near the interface was more pronounced than in sample A after long-term cycling. Regarding air stability, the H2S release of sample B in the above environmental exposure experiment was much higher than that of sample A, indicating that fluorine doping alone failed to effectively suppress the reaction of the material with trace moisture.

[0072] The comparison between samples A and B shows that the synergistic doping of oxygen and fluorine significantly improves the chemical stability and battery interface stability of the material while maintaining high ionic conductivity. Although the room temperature ionic conductivity of sample A is slightly lower than that of sample B, it is still within 10. −3 The S / cm ratio is on the order of 1,000 and meets application requirements; more importantly, sample A imparts excellent cycle life and environmental stability to the battery, which sample B cannot achieve. Therefore, the O / F synergistic doping strategy of this invention has significant advantages over single doping schemes and can significantly improve the overall performance of sulfide solid electrolytes.

[0073] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A Li-Y-Zr-Cl-S sulfide solid electrolyte material containing O / F co-doped components, characterized in that, The chemical general formula is: Li a (Y x Zr 1-x ) b Cl  c-y F y S  d-z O z , where: 0 < x < 1, the value range of a is 5 to 10, the value range of b is 0.5 to 2, the value range of c is 1 to 3, the value range of d is 4 to 12, y / c is 0.05 to 0.5, and z / d is 0.01 to 0.

2.

2. The Li-Y-Zr-Cl-S sulfide solid electrolyte material with O / F co-doping according to claim 1, characterized in that, x:(1-x) is between 0.1:0.9 and 0.9:0.

1.

3. The Li-Y-Zr-Cl-S sulfide solid electrolyte material with O / F co-doping according to claim 2, characterized in that, x:(1-x) = 0.5:0.

5.

4. The Li-Y-Zr-Cl-S sulfide solid electrolyte material with O / F co-doping according to claim 1, characterized in that, y / c is 0.1~0.3, and z / d is 0.05~0.

1.

5. A method for preparing a Li-Y-Zr-Cl-S sulfide solid electrolyte material containing O / F co-doping as described in any one of claims 1-4, characterized in that, Includes the following steps: Step 1, Raw material preparation: Under the protection of an inert atmosphere, weigh out Li2S, LiCl, LiF, Li2O, YCl2, and ZrCl4 raw materials according to the target chemical formula stoichiometric ratio; Step 2, ball milling and mixing: The raw material mixture is ball milled at 300~500 rpm for 10~30 hours under inert gas protection to obtain precursor powder; Step 3, heat treatment reaction: The precursor powder is kept at 200~500℃ for 2~5 hours under an inert atmosphere and then naturally cooled to room temperature; Step 4, Powder treatment: Grind and sieve in an inert atmosphere to obtain electrolyte powder; optionally, perform short-time sintering at about 500°C.

6. The method for preparing a Li-Y-Zr-Cl-S sulfide solid electrolyte material with O / F co-doping according to claim 5, characterized in that, Step five also includes cold pressing the electrolyte powder into electrolyte discs under a pressure of 200-500 MPa, or preparing an electrolyte membrane through a coating process.

7. The application of a Li-Y-Zr-Cl-S sulfide solid electrolyte material containing O / F synergistic doping as described in any one of claims 1-4 in an all-solid-state lithium battery, characterized in that, The all-solid-state lithium battery includes a high-voltage positive electrode, a lithium metal or lithium-free negative electrode, and an electrolyte membrane made of the electrolyte material.

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