Halide solid-state electrolyte material and preparation method therefor, lithium ion battery

Abstract

Provided are a halide solid-state electrolyte material and a preparation method therefor, a solid-state electrolyte membrane, and a lithium ion battery. The chemical formula of the halide solid-state electrolyte material is LixTayInzCl6, wherein y / x is from 0.04 to 1, z=(6-x-5y) / 3, and 1>z>0.2. The halide solid-state electrolyte material has better ionic conductivity, can be prepared by a solution method, involves a simple preparation process and low preparation cost, and can meet the requirements of large-scale production.

Description

Halide solid electrolyte material, preparation method thereof and lithium ion battery

[0001] The present application claims priority to the Chinese patent application No. 202410716645.9, filed on June 04, 2024, to the Chinese Patent Office, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of batteries, in particular to a halide solid electrolyte material, a preparation method thereof and a lithium ion battery. BACKGROUND

[0003] Solid electrolytes have the advantages of safety, stability, high pressure resistance and the like, and play a crucial role in lithium batteries and other ion batteries.

[0004] In the current solid electrolyte system, halide solid electrolyte materials have attracted much attention due to their good stability to cathodes. In order to better realize the commercialization of the materials and promote the development of solid electrolytes, it is urgent to develop halide solid electrolyte materials with high performance. TECHNICAL PROBLEM TECHNICAL SOLUTION

[0005] Embodiments of the present application provide a halide solid electrolyte material, a preparation method thereof and a lithium ion battery, which have high lithium ion conductivity.

[0006] In a first aspect, embodiments of the present application provide a halide solid electrolyte material, the chemical formula of the halide solid electrolyte material being Li x Ta y In z Cl6, wherein y / x = 0.04-1, z = (6-x-5y) / 3, 1>z>0.2.

[0007] Optionally, in some embodiments of the present application, y / x = 0.2-0.6; and / or,

[0008] The ion conductivity of the halide solid electrolyte material is greater than or equal to 1 mS / cm; and / or,

[0009] The average particle size of the halide solid electrolyte material is 1-5 μm.

[0010] Optionally, in some embodiments of the present application, the ion conductivity of the halide solid electrolyte material is 1-3 mS / cm.

[0011] Optionally, in some embodiments of the present application, the halide solid electrolyte material is selected from Li2Ta 0.5 In 0.5Cl6, Li 1.6 Ta 0.7 In 0.3 Cl6, Li 1.2 Ta 0.9 In 0.1 Cl6, Li 2.8 Ta 0.1 In 0.9 one or more of Cl6.

[0012] In a second aspect, the embodiments of the present application provide a preparation method of a halide solid-state electrolyte material, comprising the following steps:

[0013] providing a first mixture comprising lithium chloride, indium chloride, tantalum chloride and anhydrous alcohol solvent;

[0014] heating the first mixture to obtain a crystalline body;

[0015] heat-treating the crystalline body to obtain a halide solid-state electrolyte.

[0016] Optionally, in some embodiments of the present application, the molar ratio of Li in the lithium chloride, Ta in the tantalum chloride and In in the indium chloride is x:y:z, wherein y / x = 0.04-1 and z = (6-x-5y) / 3, 1>z>0.2; and / or,

[0017] the anhydrous alcohol solvent comprises one or more of anhydrous alcohol solvents with a carbon atom number of 1-8; the anhydrous alcohol solvents with a carbon atom number of 1-8 comprise one or more of anhydrous methanol, anhydrous ethanol, anhydrous propanol, anhydrous butanol, anhydrous pentanol, anhydrous hexanol, anhydrous heptanol, anhydrous ethylene glycol, and anhydrous glycerol; and / or,

[0018] the lithium chloride, the indium chloride and the tantalum chloride are solid-phase materials, and the volume of the anhydrous alcohol solvent added per gram of the solid-phase materials is 10-50 mL.

[0019] Optionally, in some embodiments of the present application, in the step of heating the first mixture to obtain a crystalline body, the heating temperature is 60-100°C; and / or,

[0020] In the step of heating the first mixture to obtain a crystalline body, the heating time is 1-10 h; and / or,

[0021] The step of providing a first mixture comprising lithium chloride, indium chloride, tantalum chloride and anhydrous alcohol solvent comprises mixing lithium chloride, indium chloride, tantalum chloride and anhydrous alcohol solvent and heating at 50-70°C for 2-10 h.

[0022] Optionally, in some embodiments of the present application, the step of heat treating the crystal to obtain the halide solid-state electrolyte material,

[0023] the temperature of the heat treatment is 120-250℃; and / or,

[0024] the heating time is 2-12h; and / or,

[0025] the heat treatment is performed under vacuum, and the vacuum degree is 0.5x10 -3 -2x10 -3 Torr.

[0026] In a third aspect, the embodiments of the present application provide a solid-state electrolyte film, the material of the solid-state electrolyte film comprising the halide solid-state electrolyte material described above, or the halide solid-state electrolyte material prepared by the preparation method described above.

[0027] In a fourth aspect, the embodiments of the present application provide a lithium ion battery, comprising oppositely arranged positive and negative electrode sheets, and a solid-state electrolyte film arranged between the positive and negative electrode sheets, the solid-state electrolyte film comprising the solid-state electrolyte film described above. Advantages

[0028] In the technical solutions provided by the present application, a new halide solid-state electrolyte material is provided, which has better ionic conductivity, and can be prepared by a solution method, has a simple preparation process, low preparation cost, and can meet large-scale production requirements. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0030] Fig. 1 is a flowchart of a preparation method of a halide solid-state electrolyte material provided by the embodiments of the present application;

[0031] Fig. 2 is an X-ray diffraction analysis spectrum of the halide solid-state electrolyte material prepared in Example 1;

[0032] Fig. 3 is an electrochemical impedance test curve of the halide solid-state electrolyte material prepared in Example 1. Embodiments of the present application

[0033] With reference to the drawings, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work fall within the scope of the present application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art. The materials and reagents used in the examples and comparative examples of the present application are commercially available unless otherwise defined. In addition, any method and material similar or equivalent to those described herein can be used in the present application. The preferred methods and materials described herein are only for illustration and should not be construed as limiting the scope of the present application.

[0035] It should be noted that the sequence of the following embodiments is not intended to limit the preferred sequence of the embodiments. Each embodiment of the present application can exist in a range of forms; it should be understood that the description in a range of forms is only for convenience and brevity, and should not be understood as a hard limit on the scope of the present application; therefore, it should be considered that the range described has been specifically disclosed all possible sub-ranges and single values within the range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. In addition, whenever a numerical range is indicated in this document, it refers to any cited number (fraction or integer) within the indicated range.

[0036] In the description of the present application, the term "comprising" means "including but not limited to".

[0037] The term "a plurality of", "a plurality of times" or similar expressions refers to two or more, for example, can be two, three, four, five, six, etc.

[0038] The selection range of the term "and / or" includes any one of the two or more related listed items, and also includes any and all combinations of the related listed items, including any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" includes three parallel schemes of A, B, and A+B. For another example, the technical scheme of "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, and D (i.e., a technical scheme connected by "logical or"), and also includes any and all combinations of A, B, C, and D, that is, to include a combination of any two or any three of A, B, C, and D, and also to include a four-item combination of A, B, C, and D (i.e., a technical scheme connected by "logical and").

[0039] The term "solid content" refers to the proportion of the mass of the solid in the slurry to the total mass of the slurry.

[0040] Ta-based halide electrolyte such as LiTaCl6 and LiTaOCl4 is one of halide solid electrolyte materials. The preparation of Ta-based halide electrolyte material needs to use raw materials such as tantalum chloride (TaCl5) and lithium chloride (LiCl). However, due to the great difference between the melting points of TaCl5 and LiCl and the existence of glass phase in high-performance phases, it is difficult to obtain high-performance phases by traditional solid-phase reaction method. Therefore, at present, Ta-based halide electrolyte is generally prepared by high-energy ball milling combined with annealing process. However, high-energy ball milling needs high-cost instrument and equipment, and the yield of one ball milling is very low (about 1-3 g), which is only suitable for small laboratory scale. At present, Ta-based halide electrolyte is difficult to be prepared on a large scale.

[0041] In a first aspect, the embodiments of the present application provide a halide solid electrolyte material, the chemical formula of the halide solid electrolyte material is Li x Ta y In z Cl6. Wherein, x, y, z need to meet the following conditions: in some embodiments, the ratio of y to x, that is, y / x, is in the range of 0.04 to 1, for example, y / x can be 0.04, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1 and a value between any two of the above values; in some embodiments, the relationship between x, y and z can meet: z=(6-x-5y) / 3, and 1>z>0.2.

[0042] The halide solid electrolyte material with the above chemical formula and x, y, z meeting the above conditions not only has better ionic conductivity, but also can be prepared by solution method to prepare the material with high-performance phase, the preparation process is simple, the preparation cost is low, and the large-scale production requirements can be realized.

[0043] In some embodiments, y / x is further selected from a value in the range of 0.2 to 0.6, for example, can be 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, and a value between any two of the above values; when y / x is selected from the above range, the performance of the material is further improved.

[0044] In some embodiments, the ionic conductivity of the halide solid-state electrolyte material is greater than or equal to 1 mS / cm; the halide solid-state electrolyte material has a better ionic conductivity, which can be used to prepare a solid-state electrolyte film of a lithium battery, to obtain a lithium battery with better performance. In other embodiments, the ionic conductivity of the halide solid-state electrolyte material can also reach 1-3 mS / cm, for example, 1 mS / cm, 1.5 mS / cm, 2 mS / cm, 2.5 mS / cm, 3 mS / cm, and a value between any two of the above values. The ionic conductivity can be detected by an electrochemical workstation commonly used in the art.

[0045] In some embodiments, the average particle size of the halide solid-state electrolyte material is 1-5 μm, for example, can be 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, and a value between any two of the above values.

[0046] In some specific embodiments, the halide solid-state electrolyte material is selected from Li2Ta 0.5 In 0.5 Cl6, Li 1.6 Ta 0.7 In 0.3 Cl6, Li 1.2 Ta 0.9 In 0.1 Cl6, Li 2.8 Ta 0.1 In 0.9 Cl6. The above halide solid-state electrolyte material has a better ionic conductivity.

[0047] In a second aspect, the application further provides a preparation method of a halide solid-state electrolyte material, please refer to FIG. 1, the preparation method comprises the following steps:

[0048] S10, providing a first mixture comprising lithium chloride, indium chloride, tantalum chloride, and anhydrous alcohol solvent;

[0049] S20, heating the first mixture to obtain a crystal;

[0050] S30, heat treating the crystal to obtain a halide solid-state electrolyte material.

[0051] The preparation method of the embodiment has low requirements on equipment, and the desired halide solid electrolyte material can be successfully prepared by using conventional experimental equipment without the need for high-cost high-energy ball milling equipment. The preparation method of the embodiment can be used to prepare kilogram-level halide solid electrolyte materials and is suitable for industrial mass production. The halide solid electrolyte material prepared by the method of the embodiment has high lithium ion conductivity.

[0052] In some embodiments, the chemical formula of the material prepared by the preparation method of the application is Li x Ta y In z Cl6. And x, y, z satisfy y / x = 0.04-1, z = (6-x-5y) / 3, 1>z>0.2.

[0053] The anhydrous alcohol solvent refers to an anhydrous alcohol reagent with very little or no water content. In some embodiments, the water content in the anhydrous alcohol solvent can be less than or equal to 0.5 (v / v) %, and in other embodiments, the water content can be less than or equal to 0.1 (v / v) %. Lithium chloride, indium chloride and tantalum chloride can stably exist and better disperse and dissolve in the anhydrous alcohol solvent, which is helpful for the subsequent formation of stable halide solid electrolyte materials.

[0054] In some specific embodiments, the anhydrous alcohol solvent can include one or more anhydrous alcohol solvents with a carbon atom number of 1-8, that is, alcohols with a carbon atom number of 1, 2, 3, 4, 5, 6, 7 or 8 or the like. For example, the anhydrous alcohol solvent with a carbon atom number of 1-8 can include but is not limited to one or more of anhydrous methanol, anhydrous ethanol, anhydrous propanol, anhydrous butanol, anhydrous pentanol, anhydrous hexanol, anhydrous heptanol, anhydrous ethylene glycol, and anhydrous glycerol. The anhydrous alcohol solvent can be purchased on the market.

[0055] The feeding amount of the lithium chloride, the indium chloride and the tantalum chloride can satisfy that the molar ratio of Li in the lithium chloride, Ta in the tantalum chloride and In in the indium chloride is x:y:z, wherein the ratio of y to x, that is, y / x, is in the range of 0.1 to 1, for example, y / x can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1 and a value between any two of the above values; z = (6-x-5y) / 3, and 1>z>0.2. Controlling the feeding amount in the above range helps to form pure substances with stable composition and high performance, and reduces the occurrence of impurities.

[0056] The amount of the anhydrous alcohol solvent can satisfy the following conditions, for example, if the lithium chloride, the indium chloride and the tantalum chloride are regarded as solid phase materials, the volume of the anhydrous alcohol solvent added per gram of the solid phase materials is 10-50 mL, that is, when the total mass of the lithium chloride, the indium chloride and the tantalum chloride is W (unit: gram), the amount of the anhydrous alcohol solvent added is 10×W mL to 50×W mL.

[0057] In some embodiments, in the step S10, the first mixture can be obtained by dissolving solid phase materials in an anhydrous alcohol solvent, for example, the step S10 can specifically include: mixing lithium chloride, indium chloride, tantalum chloride and an anhydrous alcohol solvent, and heating at 50-70°C for 2-10 h. In order to better dissolve the solid phase materials, the mixing step can be carried out in a certain temperature environment, and the temperature can be 50-70°C, for example, 50°C, 55°C, 60°C, 65°C, 70°C and a value between any two of the above values; the mixing time can be 2-10 h (hours); for example, it can be 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h and a value between any two of the above values.

[0058] In the step S20, the first mixture is heated to volatilize and remove excess solvent in the system, and Li x Ta y In z Cl6-ROH crystal, wherein ROH refers to all organic components in the crystalline product, for example, alcohols.

[0059] In some embodiments, in the step of heating the first mixture to obtain a crystal, the heating temperature is 60-100°C; for example, it can be 60°C, 70°C, 80°C, 90°C, 100°C and a value between any two of the above values.

[0060] In some embodiments, in the step of heating the first mixture to obtain a crystal, the heating time is 1-10 h; for example, it can be 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h and a value between any two of the above values.

[0061] In the step S30, the crystal is further heat-treated to remove the organic components such as ROH in the crystal, and Li x Ta y In z Cl6 halide solid electrolyte.

[0062] In some embodiments, the temperature of the heat treatment is 120 to 250°C; for example, it can be 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, or any value between any two of the above.

[0063] In some embodiments, the heating time is 2 to 12 hours; for example, it can be 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, or any value between any two of the above.

[0064] In some embodiments, the heat treatment is performed under vacuum conditions, with a vacuum level of 0.5 × 10⁻⁶. -3 ~2×10 -3 Torr; for example, it could be 0.5 × 10 -3 Torr, 0.6×10 -3 Torr, 0.7×10 -3 Torr, 0.8×10 -3 Torr, 0.9×10 -3 Torr, 1×10 -3 Torr, 1.2×10 -3 Torr, 1.4×10 -3 Torr, 1.5×10 -3 Torr, 1.8×10 -3 Torr, 2×10 -3 Torr and any two values ​​between the above.

[0065] Thirdly, embodiments of this application also provide a solid electrolyte membrane that can be used in lithium-ion batteries. The solid electrolyte membrane is made of a halide solid electrolyte material as described above, or a halide solid electrolyte material prepared by the methods described above. The halide solid electrolyte material possesses the features and corresponding effects of all the embodiments described above. Based on this, the solid electrolyte membrane has better ionic conductivity and is easy to prepare.

[0066] Fourthly, embodiments of this application provide a lithium-ion battery, including but not limited to button cells, pouch cells, prismatic lithium-ion batteries, cylindrical lithium-ion batteries, etc. The lithium-ion battery includes a positive electrode and a negative electrode disposed opposite to each other, and a solid electrolyte membrane as described in any of the preceding embodiments, wherein the solid electrolyte membrane is disposed between the positive electrode and the negative electrode.

[0067] The technical solutions and technical effects of the present application are described in detail below through specific examples. The following examples are only some of the examples of the present application and do not specifically limit the present application.

[0068] Example 1

[0069] The solid-state electrolyte material Li x Ta y In z In Cl6, y / x = 0.25, z = (6-x-5y) / 3, specifically, x = 2, y = 0.5, z = 0.5.

[0070] The preparation steps of the solid-state electrolyte material are as follows:

[0071] 1. The total mass of the corresponding LiCl, TaCl5, and InCl3 chemical raw materials is 2g, and the molar ratio of LiCl, TaCl5, and InCl3 is 2:0.5:0.5.

[0072] 2. The above-mentioned chemical raw materials are sequentially added to 30mL of anhydrous ethanol.

[0073] 3. The mixed solution is heated to 50℃ and magnetically stirred for 2h.

[0074] 4. The stirred mixed solution is placed in a 60℃ oven and dried until crystals appear and there is no ethanol residue. The obtained crystals are the precursor product of the halide electrolyte.

[0075] 5. The above-mentioned dried precursor is placed in a vacuum drying box and heat treated at 10 -3 Torr, 180℃ for 4h to remove the organic components in the crystal product, obtaining a solid-state electrolyte material Li2Ta 0.5 In 0.5 Cl6 with an average particle size of about 3μm.

[0076] Preparation of the solid-state electrolyte film

[0077] 1. 100mg of the solid-state electrolyte material powder prepared by the above process is placed in a customized PEEK material mold with a diameter of 10mm. The assembly process is carried out in an argon glove box with water content less than 0.01ppm.

[0078] 2. After the above-mentioned mold is subjected to a pressure of 300MPa for about 1min, the densification of the halide electrolyte is realized and the lithium ion conductivity test is carried out.

[0079] The product-solid-state electrolyte material Li2Ta 0.5 In 0.5Cl6 was detected; X-ray diffraction analysis was performed on the material by using an X-ray diffractometer, and the results are shown in Fig. 2. As can be seen from the figure, the main phase of the phase can be well matched with the Li3InCl6 standard card, and the impurity peak position existing in part can be related to TaCl5 and air pollution of the sample;

[0080] To obtain the lithium ion conductivity of the material, the above material was pressed into a sheet, and then was sent into an electrochemical workstation to perform electrochemical impedance test on the material. The test frequency range was 1 Hz-10 MHz. After detection, the electrochemical impedance test curve of the material is shown in Fig. 3. As can be calculated from the figure, the lithium ion conductivity of the material is 2.03 mS / cm. The electrochemical impedance is a vector, which is often written in a complex form. The complex number is composed of a real part and an imaginary part. In Fig. 3, Z' represents the real part of the impedance, and -Z" represents the negative number of the imaginary part of the impedance.

[0081] Example 2

[0082] This example is basically the same as Example 1, except that in step (1) of this example, the total mass of LiCl, TaCl5 and InCl3 chemical raw materials is changed to 30 g, and the amount of anhydrous ethanol is adjusted to 900 mL accordingly. Except for this, the other parameters and steps are unchanged.

[0083] Example 3

[0084] This example is basically the same as Example 1, except that in step (1) of this example, the total mass of LiCl, TaCl5 and InCl3 chemical raw materials is changed to 100 g, and the amount of anhydrous ethanol is adjusted to 1500 mL accordingly. Except for this, the other parameters and steps are unchanged.

[0085] Example 4

[0086] This example is basically the same as Example 1, except that in the target product halide solid electrolyte material of this example, the elemental composition of the raw material proportion parameters x = 2.8, y = 0.1, z = 0.9; accordingly, in step (1) of this example, the molar ratio of LiCl, TaCl5 and InCl3 is 2.8:0.1:0.9. Except for this, the other parameters and steps are unchanged.

[0087] Example 5

[0088] This example is basically the same as Example 1, except that in step (1) of this example, the volume of anhydrous ethanol is changed to 15 mL. Except for this, the other parameters and steps are unchanged.

[0089] Example 6

[0090] This example is basically the same as example 1, the only difference is that in step (1) of this example, the volume of anhydrous ethanol is changed to 100 mL. Except for this, other parameters and steps are the same.

[0091] Example 7

[0092] This example is basically the same as example 1, the only difference is that in step (1) of this example, the heat treatment temperature is changed from 180°C to 100°C. Except for this, other parameters and steps are the same.

[0093] Comparative Example 1

[0094] This comparative example is basically the same as example 1, the only difference is that in the target product halide solid-state electrolyte material of this comparative example, the elemental composition is that the raw material ratio parameters x = 1, y = 1.2 (y / x = 1.2), z = 0.1; correspondingly, in step (1) of this comparative example, the raw material ratio is that the molar ratio of LiCl, TaCl5, InCl3 is 1:1.2:0.1. Except for this, other parameters and steps are the same. The product formed after step (1) of this comparative example may not be a pure substance, but contains multiple impurity phases. Its nominal composition may be LiTa 1.2 In 0.1 Cl6.

[0095] Comparative Example 2

[0096] This comparative example is basically the same as example 1, the only difference is that in the target product halide solid-state electrolyte material of this comparative example, the elemental composition is that the raw material ratio parameters x = 1.2, y = 0.9 (y / x = 0.75), z = 0.1; correspondingly, in step (1) of this comparative example, the raw material ratio is that the molar ratio of LiCl, TaCl5, InCl3 is 1.2:0.9:0.1. Except for this, other parameters and steps are the same.

[0097] Comparative Example 3

[0098] This comparative example is basically the same as example 1, the only difference is that in the target product halide solid-state electrolyte material of this comparative example, the elemental composition is that the raw material ratio parameters x = 1, y = 1, z = 0; correspondingly, in step (1) of this comparative example, no indium chloride is added to the raw material, and the molar ratio of LiCl, TaCl5 is 1:1. Except for this, other parameters and steps are the same.

[0099] Comparative Example 4

[0100] This comparative example is basically the same as example 1, the only difference is that in step (1) of this comparative example, InCl3 is changed to LaCl3, and correspondingly, the nominal composition of the solid-state electrolyte material of this example may be Li2Ta 0.5 La0.5 C16. Except for this, other parameters and steps remain unchanged.

[0101] Comparative Example 5

[0102] This comparative example is basically the same as Example 1, the only difference is that in step (1) of this comparative example, TaCl5 chemical raw material is replaced by LaCl3, and accordingly, the nominal composition of the solid electrolyte material of this example can be Li3La 0.5 In 0.5 C16. Except for this, other parameters and steps remain unchanged.

[0103] Comparative Example 6

[0104] This comparative example is basically the same as Example 1, the only difference is that in step (1) of this example, anhydrous ethanol is replaced by an ethanol solution with a volume concentration of 75 (v / v) %. Except for this, other parameters and steps remain unchanged. In step (1) of this comparative example, after the chemical raw materials are added to the ethanol solution, precipitates appear, and the raw materials cannot stably exist in the solution system, making it difficult to form compositionally stable crystalline bodies in the subsequent synthesis step, and the synthesis step is therefore terminated.

[0105] Experimental Example

[0106] The halide solid electrolyte materials prepared in Examples 1 to 7 and Comparative Examples 1 to 5 above were subjected to ion conductivity detection, and the results are recorded in Table 1. The detection method of the ion conductivity can refer to the detection method in Example 1.

[0107] Table 1

[0108] From the above table, it can be seen that:

[0109] In Examples 1 to 3, as the amount of raw materials increases, the yield of the product halide solid electrolyte material also increases accordingly, indicating that the method of the present application can be used to prepare products with large yields and can be suitable for large-scale production.

[0110] Compared with Comparative Example 1 and Comparative Example 2, Examples 1 to 7 all have relatively high ion conductivity, while the two comparative examples exhibit extremely low ion conductivity, indicating that when x, y, z satisfy y / x = 0.04-1, z = (6-x-5y) / 3, 1>z>0.2, it is beneficial to form high-performance materials; further, in the examples, Example 1 exhibits the best ion conductivity, and in comparison, the ion conductivity of Examples 4 to 7 is relatively low, indicating that when y / x is in the range of 0.2-0.6, the amount of anhydrous alcohol solvent is controlled to be 10-50 mL / g of solid phase material, and the heat treatment temperature is in the range of 120-250°C, it is more beneficial to improve the performance of the material.

[0111] Comparative Examples 3 to 4 both show far lower ionic conductivities than Example 1, which can be because the incorporation of In can promote the reaction to proceed in the forward direction, and in the heating and heat treatment stages, the presence of a stable product structure can be ensured, and thus a high-performance material is obtained;

[0112] In Comparative Example 5, Ta is replaced by La, and although an electrolyte material with certain performance can be prepared, the ionic conductivity is low, far lower than the ionic conductivity level of Example 1, indicating that the combination of Li, Ta and In is more conducive to forming a high-performance and stable material;

[0113] In addition, Comparative Example 6 is terminated because the raw materials cannot stably exist in the ethanol solution, indicating that the use of anhydrous alcohol as the solvent in the solution system in the present application is conducive to the stable existence and dissolution of the raw materials, and is helpful for subsequent reactions to proceed, and thus a material with a stable composition is obtained.

[0114] The above describes the embodiments of the present application in detail, and the principles and implementation modes of the present application are described by applying specific examples; the above description of the embodiments is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed; in view of the above, the content of the specification should not be understood as a limitation of the present application.

Claims

1. A halide solid-state electrolyte material, the halide solid-state electrolyte material having a chemical formula of Li x Ta y In z Cl6, wherein, y / x = 0.04-1, z = (6-x-5y) / 3, 1>z>0.

2.

2. The halide solid-state electrolyte material of claim 1, wherein, y / x = 0.2-0.

6.

3. The halide solid-state electrolyte material of claim 1, wherein, The ion conductivity of the halide solid-state electrolyte material is greater than or equal to 1 mS / cm.

4. The halide solid-state electrolyte material of claim 1, wherein, The average particle size of the halide solid-state electrolyte material is 1-5 μm.

5. The halide solid-state electrolyte material of claim 3, wherein, The ion conductivity of the halide solid-state electrolyte material is 1-3 mS / cm.

6. The halide solid-state electrolyte material of any one of claims 1 to 5, wherein, The halide solid-state electrolyte material is selected from Li2Ta 0.5 In 0.5 Cl6, Li 1.6 Ta 0.7 In 0.3 Cl6, Li 1.2 Ta 0.9 In 0.1 Cl6, Li 2.8 Ta 0.1 In 0.9 Cl6.

7. A method of preparing a halide solid state electrolyte material, wherein, The method comprises the following steps: A first mixture comprising lithium chloride, indium chloride, tantalum chloride and anhydrous alcohol solvent is provided; The first mixture is heated to obtain a crystalline body; The crystalline body is heat-treated to obtain a halide solid-state electrolyte material.

8. The production method according to claim 7, wherein The molar ratio of Li in the lithium chloride, Ta in the tantalum chloride and In in the indium chloride is x:y:z, wherein y / x = 0.04-1, z = (6-x-5y) / 3, 1>z>0.

2.

9. The preparation method of claim 7, wherein, The anhydrous alcohol solvent comprises one or more of anhydrous alcohols with carbon atom number of 1-8; the anhydrous alcohols with carbon atom number of 1-8 comprise one or more of anhydrous methanol, anhydrous ethanol, anhydrous propanol, anhydrous butanol, anhydrous pentanol, anhydrous hexanol, anhydrous heptanol, anhydrous glycol and anhydrous glycerol.

10. The preparation method of claim 7, wherein, The lithium chloride, the indium chloride and the tantalum chloride are solid-phase materials, and the volume of the anhydrous alcohol solvent added per gram of the solid-phase materials is 10-50 mL.

11. The method of making according to claim 7, wherein, In the step of heating the first mixture to obtain a crystalline body, the heating temperature is 60-100°C.

12. The preparation method of claim 7, wherein, In the step of heating the first mixture to obtain a crystalline body, the heating time is 1-10 h.

13. The method of making according to claim 7, wherein, The step of providing a first mixture comprising lithium chloride, indium chloride, tantalum chloride and anhydrous alcohol solvent comprises mixing the lithium chloride, the indium chloride, the tantalum chloride and the anhydrous alcohol solvent and heating at 50-70°C for 2-10 h.

14. The method of making according to claim 7, wherein, In the step of heat-treating the crystalline body to obtain a halide solid-state electrolyte material, The heat-treatment temperature is 120-250°C.

15. The method of making according to claim 7, wherein, The heating time is 2-12 h.

16. The method of making according to claim 7, wherein, The heat treatment is performed under vacuum conditions, and the vacuum degree is 0.5 x 10 -3 Torr ~ 2 x 10 -3 Torr.

17. The method of making according to claim 7, wherein, y / x = 0.2-0.

6.

18. The method of making according to claim 7, wherein, The halide solid-state electrolyte material is selected from Li2Ta 0.5 In 0.5 Cl6, Li 1.6 Ta 0.7 In 0.3 Cl6, Li 1.2 Ta 0.9 In 0.1 Cl6, Li 2.8 Ta 0.1 In 0.9 Cl6.

19. The method of making according to claim 7, wherein, The ion conductivity of the halide solid-state electrolyte material is greater than or equal to 1 mS / cm.

20. A lithium-ion battery, wherein, The battery comprises oppositely arranged positive and negative electrode sheets and a solid-state electrolyte film arranged between the positive and negative electrode sheets, wherein the solid-state electrolyte film comprises the halide solid-state electrolyte material of any one of items 1 to 6 or is prepared by the preparation method of any one of claims 7 to 19.

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