Preparation method of halide electrolyte material and halide electrolyte material

Abstract

The embodiment of the invention discloses a preparation method of a halide electrolyte material and the halide electrolyte material. The preparation method of the halide electrolyte material comprises the following steps: providing a lithium source compound and halogen metal salt; mixing a lithium source compound and halogen metal salt according to a preset molar ratio to obtain a mixture; carrying out pressurization treatment, heating treatment and stirring treatment on the mixture to obtain an intermediate product; and carrying out cooling treatment and pressure reduction treatment on the intermediate product to obtain the halide electrolyte material. According to the preparation method of the halide electrolyte material, the halide electrolyte material is prepared through continuous operation of pressurizing, heating and stirring on the mixture of the lithium source compound and the halogen metal salt, a one-pot process is adopted, the process is simplified, consumed time is shortened, the preparation cost is reduced, and large-scale production is easy; meanwhile, the reactant contact area is increased, the reaction efficiency is improved, and the electrochemical stability of the halide electrolyte material is improved.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery technology, and in particular to a method for preparing a halide electrolyte material and the halide electrolyte material itself. Background Technology

[0002] With the rapid development of industries such as new energy vehicles and large-scale energy storage, the market has put forward higher requirements for the energy density and intrinsic safety of lithium-ion batteries. However, the performance of traditional lithium-ion batteries is approaching its development limit, making it difficult to meet the demand for long driving range and stringent safety standards at the same time. This has become a key bottleneck restricting further breakthroughs in the new energy field. To solve this contradiction, the industry generally regards all-solid-state batteries as the core development direction of the next generation of lithium batteries.

[0003] Currently, all-solid-state batteries are mainly classified into polymer, oxide, and sulfide types. However, polymer and oxide batteries are limited by their inherent material properties and are mostly only compatible with semi-solid-state battery systems, leading to safety hazards such as electrolyte leakage and high-temperature thermal runaway. Sulfides have poor chemical stability and are prone to side reactions with positive and negative electrode materials during battery cycling, which not only shortens the battery cycle life but also causes continuous performance degradation, severely limiting their industrial application. Halide electrolytes, especially oxygen-containing compounds, have advantages over other types of electrolytes, such as relatively high ionic conductivity and good processing performance, and their electrochemical stability is significantly higher than that of sulfide electrolytes, effectively avoiding side reactions with positive electrode materials. However, existing preparation methods mainly focus on high-energy ball milling, high-temperature calcination, and freeze-drying spray methods, which are costly, complex, and require multiple pretreatment and post-treatment steps, demanding strict process control precision. They are also time-consuming, with ball milling requiring up to 40 hours and subsequent annealing, resulting in a long overall preparation cycle that is difficult to meet the needs of large-scale production.

[0004] Therefore, it is particularly important to develop a method for preparing halide electrolyte materials that can be prepared by continuous operation of pressurizing, heating and stirring a mixture of lithium source compounds and halide metal salts, using a one-pot process to simplify the process, shorten the time, reduce the preparation cost and facilitate large-scale production, while increasing the contact area of ​​reactants, improving the reaction efficiency and enhancing the electrochemical stability of halide electrolyte materials. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a method for preparing halide electrolyte materials and halide electrolyte materials. The method involves a continuous process of pressurizing, heating, and stirring a mixture of lithium source compounds and halogen metal salts to prepare halide electrolyte materials. This addresses the current lack of a method for preparing halide electrolyte materials that can utilize a one-pot process, simplify the process, shorten the time required, reduce preparation costs, facilitate large-scale production, increase the contact area of ​​reactants, improve reaction efficiency, and enhance the electrochemical stability of the halide electrolyte materials.

[0006] The technical solution provided in this application is as follows: On one hand, this application provides a method for preparing a halide electrolyte material, characterized in that the method for preparing the halide electrolyte material includes: Provide lithium source compounds and halogen metal salts; The lithium source compound and the halogen metal salt are mixed in a preset molar ratio to obtain a mixture; The mixture is subjected to pressure treatment, heating treatment and stirring treatment to obtain an intermediate product; The intermediate product is subjected to cooling and depressurization treatment to obtain a halide electrolyte material.

[0007] In some optional embodiments, the pressurization, heating, and stirring of the mixture to obtain an intermediate product includes: An inert gas is introduced into the reaction apparatus containing the mixture to pressurize it, so that the gas pressure in the reaction apparatus is a first preset gas pressure; The reaction apparatus is heated to a first preset temperature, and the mixture is stirred to obtain an intermediate product.

[0008] In some optional embodiments, the first preset gas pressure is less than or equal to the target gas pressure value, the ratio of the target gas pressure value to the pressure bearing value of the reaction device is (1:3)-(1:2), and the stirring treatment time is 15min-60min.

[0009] In some alternative embodiments, the halide metal salt is a halide metal compound, and the first preset temperature is the boiling temperature of the halide metal compound.

[0010] In some optional embodiments, the halide metal salt is a mixture of multiple halide metal compounds, and the method for determining the first preset temperature includes: The mole fraction of each halogen metal compound is obtained by determining the ratio of the amount of substance of each halogen metal compound to the amount of substance of the mixture. The temperature contribution value of each halogen metal compound is obtained by multiplying its boiling temperature and its corresponding mole fraction. The sum of the temperature contribution values ​​of each of the halide metal compounds is determined to obtain the first preset temperature.

[0011] In some optional embodiments, the cooling and depressurization treatment of the intermediate product to obtain the halide electrolyte material includes: The reaction apparatus containing the intermediate product is cooled to bring the temperature in the reaction apparatus to a second preset temperature. The inert gas is introduced into the reaction device to reduce the pressure so that the gas pressure in the reaction device is a second preset pressure, thereby obtaining the halide electrolyte material.

[0012] In some optional embodiments, the second preset temperature is 15℃-30℃, and the second preset air pressure is 0.1MPa-0.15MPa.

[0013] In some alternative embodiments, the inert gas is one of nitrogen or argon.

[0014] In some alternative embodiments, the lithium source compound is lithium hydroxide.

[0015] On the other hand, this application provides a halide electrolyte material, which is prepared by the preparation method described in any one of the above embodiments.

[0016] The method for preparing halide electrolyte materials provided in this application includes: providing a lithium source compound and a halogen metal salt; mixing the lithium source compound and the halogen metal salt according to a preset molar ratio to obtain a mixture; subjecting the mixture to pressure treatment, heating treatment, and stirring treatment to obtain an intermediate product; and subjecting the intermediate product to cooling treatment and depressurization treatment to obtain the halide electrolyte material. The method for preparing halide electrolyte materials through continuous operation of pressurizing, heating, and stirring the mixture of lithium source compound and halogen metal salt employs a one-pot process, simplifying the process, shortening the time, reducing preparation costs, and facilitating large-scale production. Simultaneously, it increases the contact area of ​​reactants, improves reaction efficiency, and enhances the electrochemical stability of the halide electrolyte material. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of a method for preparing halide electrolyte materials according to an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the principle of preparing halide solid electrolyte materials via solid-solid reaction. Figure 3 This is a schematic diagram illustrating the principle of preparing halide solid electrolyte materials through solid-liquid reaction. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] The term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this application. In the description of this application, it should be understood that the terms "upper," "lower," "top," "bottom," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Moreover, the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein.

[0021] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to an integer, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are included. For example, a specified range from “1 to 10” should be considered to include any and all subranges between the minimum value 1 and the maximum value 10. Exemplary subranges of the range 1 to 10 include, but are not limited to, 1 to 6.1, 3.5 to 7.8, 5.5 to 10, etc.

[0022] Current methods for preparing halide electrolytes mainly involve high-energy ball milling, high-temperature calcination, and freeze-drying spray methods. These methods are costly, complex, and often require multiple pre- and post-treatment steps, demanding stringent process control precision. They are also time-consuming, with ball milling lasting up to 40 hours followed by annealing, resulting in a long overall preparation cycle that is difficult to meet the demands of large-scale production. Therefore, to simplify the process, shorten the time required, reduce preparation costs, and facilitate large-scale production, while simultaneously increasing the contact area of ​​reactants, improving reaction efficiency, and enhancing the electrochemical stability of halide electrolyte materials, this application provides a method for preparing halide electrolyte materials and the halide electrolyte material itself.

[0023] Please see Figure 1 , Figure 1 This is a schematic flowchart of a method for preparing a halide electrolyte material according to an embodiment of the present invention. In one aspect, this application provides a method for preparing a halide electrolyte material, the method comprising: S101. Provides lithium source compounds and halogen metal salts.

[0024] In an optional embodiment, the lithium source compound is lithium hydroxide.

[0025] Optionally, a lithium source compound is used to provide Li in the product. + Li + It is the key charge carrier for ion conduction in halide electrolytes, affecting the ionic conductivity of the final product. Simultaneously, the selected lithium source compound must also provide oxygen to meet the structural requirements of the halide oxide. The chemical formula of the halide metal salt is M. m X xExamples of these include NbCl5, TaCl5, and NbBr5. M represents transition metal ions, including but not limited to niobium (Nb) and tantalum (Ta); X represents halide ions, such as Cl, Br, and F, which determine the crystal structure and stability of the electrolyte and are crucial components for maintaining electrolyte neutrality and ion conduction channels.

[0026] The selected lithium source compounds and halogen metal salts are both in solid form and require no pretreatment. They can be directly weighed and added to the high-pressure reactor, avoiding the cumbersome pretreatment steps of traditional methods such as high-energy ball milling, greatly simplifying the process and shortening the preparation cycle.

[0027] S102. The lithium source compound and the halogen metal salt are mixed in a preset molar ratio to obtain a mixture.

[0028] Alternatively, the reaction equation is: ; Optionally, the preset molar ratio is LiOH to M m X x The molar ratio is 1:a, and the value of 'a' must satisfy the atomic balance of the four elements Li, M, X, and O to ensure that the product strictly follows the general structural formula of LMOX and that no excess impurity ions are generated. The value of 'a' is not fixed and only needs to be adapted to the composition requirements of the target product. For example, when preparing a single metal halide oxide, a=1, that is, 1 mole of LiOH corresponds to 1 mole of a single halide metal salt; when preparing a complex metal halide oxide, a is the total molar amount of multiple halide metal salts, and the ratio between each salt can be flexibly adjusted. As long as the total molar amount meets the numerical requirement of 'a', atomic conservation can be achieved.

[0029] Optionally, the halide metal salt can be a single compound, or multiple halide metal compounds can be mixed according to the product performance requirements, following the principle of molar ratio balance. For example, in preparing LNOC (LiNbOCl), a single halide metal salt, NbCl5, is selected and mixed at a molar ratio of 1 part lithium source compound (LiOH) to 1 part NbCl5; to prepare LNTOC (LiNb... 0.5 Ta 0.5 When mixing NbCl5 and TaCl5 in a molar ratio of 0.5:0.5, and then mixing with 1 part LiOH, it is necessary to adjust the total molar amount of the halogen metal salt to ensure that the Li, M, X, and O elements react in the structural proportions of the target product LMOX, without introducing any excess impurity ions, by adjusting the total molar amount of the halogen metal salt.

[0030] Optionally, LiOH reacts with a halide metal salt M m X xThe reaction generates HX gas, which can be controlled and discharged during the pressure control process in the high-pressure reactor. It will not remain in the product, effectively preventing the accumulation of impurities and ensuring the high purity of the halide electrolyte.

[0031] The mixing process achieves macroscopic uniform contact of the raw materials. Both raw materials are in solid form, and after mixing in proportion, they can form a uniformly dispersed solid mixture. This avoids incomplete reaction caused by excessive or insufficient local raw materials. The mixing process does not require any additional pretreatment steps. The solid LiOH and solid halogen metal salt, weighed according to the preset molar ratio, are directly added to the high-pressure reactor, which is suitable for the one-pot process and greatly shortens the preparation cycle.

[0032] S103. The mixture is subjected to pressure treatment, heating treatment and stirring treatment to obtain an intermediate product.

[0033] In an optional embodiment, the pressurization, heating, and stirring of the mixture to obtain an intermediate product includes: An inert gas is introduced into the reaction apparatus containing the mixture to pressurize it, so that the gas pressure in the reaction apparatus is a first preset gas pressure; The reaction apparatus is heated to a first preset temperature, and the mixture is stirred to obtain an intermediate product.

[0034] In an optional embodiment, the inert gas is either nitrogen or argon.

[0035] In an optional embodiment, the first preset gas pressure is less than or equal to the target gas pressure value, the ratio of the target gas pressure value to the pressure bearing value of the reaction device is (1:3)-(1:2), and the stirring treatment time is 15min-60min.

[0036] Optionally, the reaction apparatus refers to a high-pressure reactor, which must have pressure bearing, pressure control, and inert gas introduction functions. Its maximum pressure bearing capacity directly determines the upper limit of the pressure. The introduced inert gas is nitrogen or argon, which serves to prevent side reactions between air and raw materials or reaction intermediates, and also acts as a pressurizing medium to ensure that the reaction system is in an inert atmosphere.

[0037] Optionally, the first preset gas pressure is less than or equal to the target gas pressure value, and greater than the saturated vapor pressure of the halogen metal salt. The target gas pressure value can be set according to actual business needs and is not limited here. For example, the ratio of the target gas pressure value to the pressure bearing value of the reaction device is 1:2, that is, the first preset gas pressure is less than or equal to half of the pressure bearing value of the reaction device.

[0038] By pressurizing with an inert gas, a high-pressure environment can be created to raise the boiling point of halogen metal salts, causing them to melt into a liquid state upon heating without boiling and volatilizing. This allows for the reaction of solid LiOH with liquid M... m X x The solid-liquid reaction system; at the same time, the inert atmosphere isolates impurities from interference, ensuring the directional formation of LMOX-type halide oxides and avoiding impurity ions from reducing product purity.

[0039] Optionally, the stirring speed and time can be set according to actual business needs and are not limited here, as long as a uniform reaction is achieved. For example, they can be adjusted according to the volume of the reactor; a lower speed can be selected for a small-volume reactor, while a higher speed can be appropriately selected for a large-volume reactor to ensure uniform reaction in the molten state. m X x When thoroughly mixed with solid LiOH, with no dead zones in the reaction, the stirring time can be 30 minutes, which ensures that the raw materials react fully without increasing energy consumption or causing excessive growth of product grains due to excessive time. Stirring should be started simultaneously with heating and continued until heating is stopped and before cooling and discharging. Stirring promotes the reaction during the heating stage, and maintaining stirring in the early stage of cooling can prevent local accumulation of product and ensure uniform particle size.

[0040] Stirring eliminates concentration and temperature gradients in the reaction system. During heating, stirring ensures uniform contact between the molten halide metal salt and LiOH, preventing the formation of byproducts caused by excessive local raw materials. Simultaneously, stirring transfers heat, ensuring consistent temperature across the reactor and preventing uneven product structure due to localized temperature variations. Furthermore, uniform stirring ensures consistent particle size in the intermediate products, laying the foundation for obtaining halide electrolyte materials with uniform particle size distribution after subsequent cooling and depressurization.

[0041] In an optional embodiment, the halide metal salt is a halide metal compound, and the first preset temperature is the boiling temperature of the halide metal compound.

[0042] In an optional embodiment, the halide metal salt is a mixture of multiple halide metal compounds, and the method for determining the first preset temperature includes: The mole fraction of each halogen metal compound is obtained by determining the ratio of the amount of substance of each halogen metal compound to the amount of substance of the mixture. The temperature contribution value of each halogen metal compound is obtained by multiplying its boiling temperature and its corresponding mole fraction. The sum of the temperature contribution values ​​of each of the halide metal compounds is determined to obtain the first preset temperature.

[0043] Optionally, if the halide metal salt is a single compound, the first preset temperature is equal to the atmospheric boiling temperature of the salt. This ensures complete melting of the salt without causing decomposition of the raw material due to excessive temperature. The high-pressure reactor is already pressurized with inert gas. Heating the temperature to the atmospheric boiling temperature of the salt at this point allows the salt to reach a molten state while suppressing boiling and volatilization through high pressure, thus avoiding raw material loss or product impurities.

[0044] Optionally, if the halide metal salt is a mixture of multiple halide metal compounds, the first preset temperature needs to be calculated by weighted summation of mole fractions to ensure that each compound in the mixture can melt while the whole mixture does not boil. The calculation formula is as follows: ; Where Treaction is the first preset temperature, nmetal salt is the mole fraction of the i-th halogen metal salt, and Tmetal salt is the atmospheric boiling temperature of that salt. The mole fraction reflects the proportion of a compound in the mixture, ensuring that compounds with higher proportions have a greater impact on the final temperature, avoiding situations where the average temperature prevents some compounds from melting. The melting temperature requirement of each compound is converted into a contribution value by multiplying its boiling point by its mole fraction. The higher the proportion of a compound, the stronger its contribution to the final temperature, ensuring that the overall mixture conforms to the melting requirements of compounds with higher proportions. The total temperature ensures that each compound in the mixture reaches a molten state, preventing some compounds from remaining undried or being overheated.

[0045] By precisely heating the halogen metal salt to a molten state, the reaction is transformed from a solid-solid reaction to a solid-liquid reaction, which greatly increases the contact area between LiOH and the halogen metal salt. The liquid salt can encapsulate the solid LiOH, and the contact efficiency is much higher than the limited contact between solid particles. Furthermore, when the temperature reaches the boiling point of the salt, the raw material has the highest activity, which can drive the reaction to generate intermediate products according to the preset equation.

[0046] Please see Figure 2 , Figure 2 This is a schematic diagram illustrating the principle of preparing halide solid electrolyte materials via solid-solid reaction. As shown in the diagram, the traditional solid-solid reaction process does not utilize high pressure to suppress M... m X x Boiling did not create the conditions for melting, and LiOH reacted with M m X xWhen particles always participate in the reaction in solid form, such as in high-energy ball milling, they need to be mixed and reacted through the impact of grinding beads within a ball mill jar. Solid particles can only achieve surface contact, with the contact area limited to a localized region on the particle surface. This creates reaction dead zones, and the uniformity of mixing depends on the milling time and intensity, making it difficult to achieve globally uniform contact. This results in a product with a wide particle size distribution and low ionic conductivity. Furthermore, additional mechanical grinding equipment or high-temperature calcination equipment is required, and the product must be transferred to glove boxes, annealing furnaces, or other equipment for post-processing after ball milling. The process is cumbersome and difficult to scale up.

[0047] Please see Figure 3 , Figure 3 This is a schematic diagram illustrating the principle of preparing halide solid electrolyte materials through solid-liquid reactions. As shown in the diagram, M is suppressed by high voltage. m X x Boil, and heat to M m X x Boiling point at normal pressure, so that M m X x It melts into a liquid state, forming solid LiOH suspended or immersed in liquid M. m X x A solid-liquid mixture system. Liquid M m X x It can encapsulate solid LiOH particles, increasing the contact area between them, eliminating dead zones in the reaction, and the stirring operation further enhances the mixing uniformity, ensuring that each LiOH particle is fully mixed with M. m X x Fully react.

[0048] S104. The intermediate product is subjected to cooling and depressurization treatment to obtain a halide electrolyte material.

[0049] In an optional embodiment, the cooling and depressurization treatment of the intermediate product to obtain the halide electrolyte material includes: The reaction apparatus containing the intermediate product is cooled to bring the temperature in the reaction apparatus to a second preset temperature. The inert gas is introduced into the reaction device to reduce the pressure so that the gas pressure in the reaction device is a second preset pressure, thereby obtaining the halide electrolyte material.

[0050] In an optional embodiment, the second preset temperature is 15℃-30℃, and the second preset air pressure is 0.1MPa-0.15MPa.

[0051] Optionally, the intermediate product is an LMOX-type halide oxide primary product generated by high-pressure heating reaction. At this stage, because the reaction temperature is maintained at the first preset temperature, the product is mostly in a molten or semi-molten state, and needs to be cooled to solidify it into solid particles. Continuous stirring is required during the cooling process. The purpose of stirring is to eliminate local temperature differences within the reactor, prevent the molten product from forming large clumps or uneven particle size distribution due to uneven cooling, and achieve a refined and uniform particle size. The cooling endpoint is the second preset temperature, which is room temperature. This can be achieved through natural cooling or simple air cooling, significantly reducing energy consumption and process complexity.

[0052] Optionally, the pressure is reduced by continuously introducing inert gas and slowly releasing the pressure inside the vessel. The pressure relief rate is controlled so that the pressure inside the vessel gradually decreases from the first preset pressure to the second preset pressure, which is atmospheric pressure. This ensures that no air rushes in due to pressure difference when the vessel is opened for discharge. The entire process is covered by an inert gas atmosphere, which not only prevents air from entering and contaminating the product, but also allows the residual HX gas inside the vessel to be discharged along with the inert gas.

[0053] Comparative Example 1: This comparative example provides a method for preparing a halide electrolyte material. The difference from the examples is that a ball milling method is used, and the prepared halide electrolyte material is LNOC. The specific preparation method is as follows: Weigh out one part LiOH and one part NbCl5 and place them in a ball mill jar, then add... Zirconia ball milling beads were used to mill the product at 500 rpm for 40 hours. The product was then removed in an argon glove box and annealed at 100°C to obtain LNOC.

[0054] Comparative Example 2: This comparative example provides a method for preparing a halide electrolyte material. The difference from the examples is that a ball milling method is used, and the prepared halide electrolyte material is LTOC. The specific preparation method is as follows: Weigh out one part LiOH and one part TaCl5 and put them into a ball mill jar, then add... Zirconia ball milling beads were used to mill the product at 500 rpm for 40 hours. The product was then removed in an argon glove box and annealed at 300°C to obtain the product LTOC.

[0055] Comparative Example 3: This comparative example provides a method for preparing a halide electrolyte material. The difference from the examples is that a ball milling method is used, and the prepared halide electrolyte material is LNTOC. The specific preparation method is as follows: Weigh out one part LiOH, 0.5 parts NbCl5, and 0.5 parts TaCl5 and place them in a ball mill jar, then add... Zirconia ball milling beads were used to mill the product at 500 rpm for 40 hours. The product was then removed in an argon glove box and annealed at 300°C to obtain the product LNTOC.

[0056] Example 1: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LNOC, and the specific preparation method is as follows: Weigh out one part LiOH and one part NbCl5 and put them into a high-pressure reactor. Pour nitrogen gas into the reactor until the internal pressure reaches 3MPa. Stir and heat to 254℃. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LNOC is removed.

[0057] Example 2: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LTOC, and the specific preparation method is as follows: Weigh out one part LiOH and one part TaCl5 and put them into a high-pressure reactor. Pour nitrogen gas into the reactor until the internal pressure reaches 3MPa. Stir and heat to 242℃. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the LTOC product is removed.

[0058] Example 3: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LTNOC, and the specific preparation method is as follows: Weigh out one part LiOH, 0.5 parts NbCl5, and 0.5 parts TaCl5 and place them into a high-pressure reactor. Purge with nitrogen until the internal pressure reaches 3 MPa, and heat to 248°C while stirring. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LTNOC is removed.

[0059] Example 4: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LTNOC, and the specific preparation method is as follows: Weigh out one part LiOH, 0.3 parts NbCl5, and 0.7 parts TaCl5 and place them into a high-pressure reactor. Purge with nitrogen until the internal pressure reaches 3 MPa, and heat to 248°C while stirring. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LTNOC is removed.

[0060] Example 5: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LTNOC, and the specific preparation method is as follows: Weigh out one part LiOH, 0.7 parts NbCl5, and 0.3 parts TaCl5 and place them into a high-pressure reactor. Purge with nitrogen until the internal pressure reaches 3 MPa, and heat to 248°C while stirring. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LTNOC is removed.

[0061] Example 6: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LNOB, and the specific preparation method is as follows: Weigh out one part LiOH and one part NbBr5 and put them into a high-pressure reactor. Pour nitrogen gas into the reactor until the internal pressure reaches 3MPa. Stir and heat to 364℃. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LNOB is removed.

[0062] Example 7: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LTOB, and the specific preparation method is as follows: Weigh out one part LiOH and one part TaBr5 and put them into a high-pressure reactor. Pour nitrogen gas into the reactor until the internal pressure reaches 3MPa. Stir and heat to 349℃. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LTOB is removed.

[0063] Example 8: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LNOBC, and the specific preparation method is as follows: Weigh out one part LiOH, 0.5 parts NbCl5, and 0.5 parts NbBr5 and place them into a high-pressure reactor. Purge with nitrogen until the internal pressure reaches 3 MPa, and heat to 309°C while stirring. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LNOBC is removed.

[0064] Example 9: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LTOBC, and the specific preparation method is as follows: Weigh out one part LiOH, 0.5 parts TaCl5, and 0.5 parts TaBr5 and place them into a high-pressure reactor. Purge with nitrogen until the internal pressure reaches 3 MPa, and heat to 295.5℃ while stirring. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LTOBC was removed.

[0065] Example 10: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LTOF, and the specific preparation method is as follows: Weigh out one part LiOH and one part TaF5 and put them into a high-pressure reactor. Purge with nitrogen until the internal pressure reaches 3MPa. Stir and heat to 229.5℃. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the LTOF product is removed.

[0066] Example 11: This embodiment provides a method for preparing a halide electrolyte material, wherein the prepared halide electrolyte material is LNOF, and the specific preparation method is as follows: Weigh out one part LiOH and one part NbF5 and put them into a high-pressure reactor. Pour nitrogen gas into the reactor until the internal pressure reaches 3MPa. Stir and heat to 236℃. Maintain the internal pressure at 3 MPa, stop heating after reacting for 30 minutes, and continue stirring until the temperature drops to room temperature. After introducing nitrogen gas into the reactor, the product LNOF is removed.

[0067] Particle size distribution statistics were performed on all halide electrolyte materials in the comparative examples and embodiments. Dry ball milling was used for fine grinding, as follows: ZrO2 balls were milled at 120 rpm with a ball-to-material ratio of 20:1 and 30:1. The particle size distribution was statistically analyzed using a particle size analyzer. The particle size distribution of the comparative example is shown in Table 1, and the particle size distribution of the example is shown in Table 2.

[0068] Table 1 Comparative particle size distribution ( )

[0069] Table 2 Particle size distribution of the examples ( )

[0070] As shown in Tables 1 and 2, electrolyte materials prepared by traditional high-energy ball milling and annealing exhibit a large particle size distribution range, significant fluctuations in median particle size (D50), and poor process stability. During ball milling, the impact and grinding forces of the milling beads are unevenly distributed within the container, resulting in over-grinding in some areas and under-grinding in others. Annealing further exacerbates the agglomeration of fine particles, further widening the particle size difference. In contrast, electrolyte materials prepared by the one-pot method in a high-pressure reactor have a highly concentrated particle size distribution, stable median particle size (D50), and strong process adaptability. This method can yield liquid M... m X x It can encapsulate solid LiOH to achieve a three-dimensional contact reaction, and the resulting intermediate products have uniform particle size, eliminating the problem of uneven surface reaction in traditional processes.

[0071] Ionic conductivity tests were performed on all halide electrolyte materials used in the comparative examples and embodiments using a Metrohm PGSTAT302 electrochemical workstation. The test frequency range was 10MHz-1Hz, with a bias voltage of 10mV. 200mg of powder was weighed for each test. The mold presses the sheet into a sheet at 350 MPa, using stainless steel as the blocking electrode. Based on the conductivity calculation formula... The total ionic conductivity was calculated, where L is the sample thickness, R is the total impedance, and S is the effective contact area between the sample and the electrode. The ionic conductivity of the comparative example is shown in Table 3, and the ionic conductivity of the example is shown in Table 4.

[0072] Table 3 Comparative examples of ionic conductivity (mS / cm)

[0073] Table 4 Ionic conductivity (mS / cm) of the examples

[0074] As can be seen in Table 3, the ionic conductivity of Comparative Examples 1, 2, and 3 is generally low and fluctuates significantly. The mixture in Comparative Example 3 exhibits low conductivity due to uneven mixing and incomplete reaction of the two halogen metal salts during ball milling. This defect stems from the inherent limitations of traditional processes; high-energy ball milling for 40 hours is insufficient to achieve the desired reaction between solid LiOH and M. m X x The complete reaction is hindered by impurities introduced during the ball milling process from the wear of zirconia balls, which further obstruct ion conduction channels. Furthermore, subsequent annealing may lead to particle agglomeration, resulting in uneven pore distribution within the electrolyte after tableting and damaging the Li... + The conduction path is continuous. In Table 4, the ionic conductivity of Examples 1-11 is significantly higher than the corresponding examples, and the numerical stability is extremely strong. This indicates that the molten M under high pressure... m X x It forms a solid-liquid reaction with solid LiOH, ensuring a complete reaction with no unreacted raw material residue. An inert gas atmosphere isolates the introduction of impurities throughout the process, resulting in high product purity. The uniform particle size distribution makes the electrolyte tablets dense and pore-free, providing a high purity for LiOH. + It provides a smooth transmission channel.

[0075] Battery performance tests were conducted on all halide electrolyte materials in the comparative examples and embodiments. 5.6 g of NMC811 cathode material and 1.372 g of the halide oxide electrolyte material powder prepared above were weighed into a 100 ml ball mill jar, and 50 g of [unspecified ingredient] was added. Zirconia balls were used for ball milling at 300 rpm for 30 minutes to obtain a mixture of positive electrode material and solid electrolyte. Then, 0.014 g of conductive carbon was added and ball milling continued at 300 rpm for 30 minutes. The ball-milled composite material was then placed in an agate grinding mill, and 0.014 g of PTFE was added. Grinding was performed using an agate grinding rod for 60 minutes. After grinding, a composite positive electrode block was obtained. This block was then repeatedly rolled in a roller press, with the upper roller temperature at 90℃ and the lower roller temperature at 100℃, until the thickness of the positive electrode sheet reached 85 mm. Stop the roller pressing at the appropriate time and place 85 The positive electrode sheet was rolled and laminated with carbon-coated aluminum foil to obtain the desired positive electrode sheet. The prepared positive electrode sheet was then cut into small circular pieces with a diameter of 10 mm using a punching machine. These pieces were then assembled with a sulfide solid electrolyte and a lithium indium anode to form an all-solid-state battery. The battery was then placed in a Blue Battery testing system for electrochemical performance testing at a rate of 0.1C. The results of the comparative cycle tests are shown in Table 5, and the results of the example cycle tests are shown in Table 6.

[0076] Table 5 Comparative Cyclic Test Results

[0077] Table 6. Cyclic Test Results of Examples

[0078] As can be seen from Table 5, the comparative examples of electrolytes prepared using the traditional high-energy ball milling method generally suffer from defects such as rapid capacity decay, large fluctuations in charge-discharge efficiency, and short cycle life, making it difficult to maintain a stable high level of performance. However, in Table 6, Examples 1-11, which use the one-pot method of the high-pressure reactor of this invention to prepare electrolytes, exhibit advantages such as high capacity retention, stable charge-discharge efficiency, and long cycle life. For example, the LNOC electrolyte in Example 1 maintained a capacity retention of over 90% after 1000 cycles, and the cycle performance of Examples 6-11 was also highly stable. This demonstrates that the electrolyte prepared by the one-pot method has high purity, uniform particle size distribution, and forms excellent interfacial contact with the positive electrode particles. + The unobstructed conduction channels effectively suppress the occurrence of interfacial side reactions during charging and discharging, thereby improving the cycle stability and effectiveness of the battery.

[0079] Therefore, the halide electrolyte material prepared in the examples is superior to the electrolyte prepared by traditional ball milling process in terms of ionic conductivity, particle size distribution and cycling results. Moreover, the preparation process is simpler, less time-consuming and easier to scale up.

[0080] On the other hand, this application provides a halide electrolyte material, which is prepared by the preparation method described in any one of the above embodiments.

[0081] The method for preparing halide electrolyte materials provided in this application includes: providing a lithium source compound and a halogen metal salt; mixing the lithium source compound and the halogen metal salt according to a preset molar ratio to obtain a mixture; subjecting the mixture to pressure treatment, heating treatment, and stirring treatment to obtain an intermediate product; and subjecting the intermediate product to cooling treatment and depressurization treatment to obtain the halide electrolyte material. The method for preparing halide electrolyte materials provided in this application has the following beneficial effects: (1) The high-pressure reactor is used for one-pot operation, which does not require solvent dissolution, drying pretreatment or multiple equipment transfer. The preparation can be completed in a continuous process of raw material input, high-pressure inert gas pressurization, heating and stirring, and cooling and depressurization, which greatly shortens the preparation cycle. At the same time, the process parameters are easy to control precisely through the equipment and are suitable for single or mixed halogen metal salt systems, which has the potential for large-scale production and effectively reduces equipment investment and operating costs. (2) By suppressing the boiling of halogen metal salts under high pressure, the halogen metal salts are melted into liquid, and the traditional solid-solid reaction is transformed into a solid-liquid reaction. This greatly increases the contact area of ​​the reactants and avoids the problem of insufficient reaction caused by uneven contact of the particle surface. In addition, the whole process is protected by inert gas, which isolates the introduction of air moisture and impurities. The product has no unreacted raw material residues and mechanical grinding impurities, which improves the purity of the product, and has high ionic conductivity and uniform particle size distribution.

[0082] The above description is only an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preparing a halide electrolyte material, characterized in that, The preparation method of the halide electrolyte material includes: Provide lithium source compounds and halogen metal salts; The lithium source compound and the halogen metal salt are mixed in a preset molar ratio to obtain a mixture; The mixture is subjected to pressure treatment, heating treatment and stirring treatment to obtain an intermediate product; The intermediate product is subjected to cooling and depressurization treatment to obtain a halide electrolyte material.

2. The method for preparing the halide electrolyte material according to claim 1, characterized in that, The mixture is subjected to pressure treatment, heating treatment, and stirring treatment to obtain an intermediate product, including: An inert gas is introduced into the reaction apparatus containing the mixture to pressurize it, so that the gas pressure in the reaction apparatus is a first preset gas pressure; The reaction apparatus is heated to a first preset temperature, and the mixture is stirred to obtain an intermediate product.

3. The method for preparing the halide electrolyte material according to claim 2, characterized in that, The first preset gas pressure is less than or equal to the target gas pressure value, the ratio of the target gas pressure value to the pressure bearing value of the reaction device is (1:3)-(1:2), and the stirring time is 15min-60min.

4. The method for preparing the halide electrolyte material according to claim 2, characterized in that, The halide metal salt is a halide metal compound, and the first preset temperature is the boiling temperature of the halide metal compound.

5. The method for preparing the halide electrolyte material according to claim 4, characterized in that, The halide metal salt is a mixture of various halide metal compounds, and the method for determining the first preset temperature includes: The mole fraction of each halogen metal compound is obtained by determining the ratio of the amount of substance of each halogen metal compound to the amount of substance of the mixture. The temperature contribution value of each halogen metal compound is obtained by multiplying its boiling temperature and its corresponding mole fraction. The sum of the temperature contribution values ​​of each of the halide metal compounds is determined to obtain the first preset temperature.

6. The method for preparing the halide electrolyte material according to claim 2, characterized in that, The intermediate product is cooled and depressurized to obtain a halide electrolyte material, comprising: The reaction apparatus containing the intermediate product is cooled to bring the temperature in the reaction apparatus to a second preset temperature. The inert gas is introduced into the reaction device to reduce the pressure so that the gas pressure in the reaction device is a second preset pressure, thereby obtaining the halide electrolyte material.

7. The method for preparing the halide electrolyte material according to claim 6, characterized in that, The second preset temperature is 15℃-30℃, and the second preset air pressure is 0.1MPa-0.15MPa.

8. The method for preparing the halide electrolyte material according to claim 6, characterized in that, The inert gas is either nitrogen or argon.

9. The method for preparing the halide electrolyte material according to claim 1, characterized in that, The lithium source compound is lithium hydroxide.

10. A halide electrolyte material, characterized in that, The halide electrolyte material is prepared using the preparation method described in any one of claims 1-9.

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