Wet chemical preparation method of electrolyte material

Abstract

The embodiment of the invention discloses a wet chemical preparation method of an electrolyte material. The wet chemical preparation method comprises the following steps: providing a halide mother solution and a lithium source solution; slowly adding the lithium source solution into the halide mother solution for coprecipitation to generate a coprecipitation product; evaporating the halide mother liquor and the lithium source solution which do not participate in coprecipitation to crystallize and separate out a coprecipitation product; and carrying out low-temperature sintering on a co-precipitation product separated by crystallization to obtain the electrolyte material. According to the wet chemical preparation method of the electrolyte material, the lithium source solution is slowly added into the halide mother solution, evaporative crystallization and coprecipitation are combined, uniform crystallization of all components can be achieved, and segregation is avoided; and the lithium source solution is slowly added, so that the solution state in the evaporation process can be changed, and the crystal granularity of the product is controllable.

Description

Technical Field

[0001] The invention relates to the field of lithium ion batteries, and in particular to a wet chemical preparation method of an electrolyte material. Background Art

[0002] Lithium-ion batteries have the characteristics of high energy density, long cycle life, and good safety, and are widely used in 3C, power vehicles, storage and other fields. All-solid-state batteries use solid electrolytes with high thermal stability, which can achieve high specific energy and high safety, and are considered to be the most promising new generation battery system. Solid electrolytes are the core materials of all-solid-state batteries, among which halide solid electrolytes have attracted widespread attention due to their low preparation cost, good high-voltage cathode compatibility and wide electrochemical window.

[0003] At present, the preparation methods of halide solid electrolytes mainly include solid phase method (high energy ball milling) and liquid phase method (evaporation crystallization, spray drying, freeze drying). The halide solid electrolyte particles prepared by the solid phase method have a large particle size and low production capacity; the spray drying method also cannot control the size of the solid electrolyte particles, and it is easy to cause the halide to hydrolyze and obtain some oxide impurities. Evaporation crystallization can control the size of solid electrolyte particles through factors such as evaporation temperature and vacuum degree, and at the same time, additives are added to the solution to inhibit the hydrolysis of halides; however, the solubility of each component of the halide electrolyte in the solvent varies greatly, and the use of conventional evaporation crystallization technology is prone to impurity segregation, which is quite different from the designed component ratio, and the traditional evaporation crystallization cannot control the growth change of crystal particle size, and the product particle size is too large.

[0004] Therefore, it is particularly important to develop a wet chemical preparation method for electrolyte materials that can avoid partial segregation of multi-component compounds due to different solubilities during the crystallization process, avoid material hydrolysis due to pH changes, improve the purity of crystalline compounds, and make the crystal size controllable. Summary of the invention

[0005] In order to solve the above-mentioned technical problems, the present application provides a wet chemical preparation method for electrolyte materials, which can solve the current problem of lack of a wet chemical preparation method for electrolyte materials that can avoid partial segregation of multi-component compounds due to different solubilities during the crystallization process, avoid material hydrolysis due to pH changes, improve the purity of crystalline compounds, and make the crystal particle size controllable.

[0006] The technical solutions provided by this application are as follows:

[0007] The present application provides a wet chemical preparation method of an electrolyte material, the wet chemical preparation method of the electrolyte material comprising:

[0008] Providing halide mother solution and lithium source solution;

[0009] Slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product; and evaporating the halide mother solution and the lithium source solution that do not participate in the co-precipitation to crystallize the co-precipitation product;

[0010] The crystallized coprecipitation product is subjected to low temperature sintering to obtain an electrolyte material.

[0011] In some optional embodiments, providing a halide mother solution and a lithium source solution comprises:

[0012] Dissolving a metal halide in distilled water to obtain a metal halide solution; dissolving a lithium source in distilled water to obtain a lithium source solution;

[0013] Dissolving the metal halide solution and the chelating agent to obtain a metal halide combined solution; dissolving the lithium source solution and the chelating agent to obtain a lithium source combined solution;

[0014] An acid solution is added to the metal halide combined solution to adjust the pH value to obtain a halide mother solution; and an acid solution is added to the lithium source combined solution to adjust the pH value to obtain a lithium source solution.

[0015] In some optional embodiments, the step of slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product; and evaporating the halide mother solution and the lithium source solution that do not participate in the co-precipitation to crystallize the co-precipitation product comprises:

[0016] Stirring, heating and vacuuming the halide mother liquor;

[0017] Slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product, wherein stirring, heating and vacuum treatment are maintained during the co-precipitation process;

[0018] While the coprecipitation is being carried out, evaporating the halide mother solution and the lithium source solution that are not involved in the coprecipitation;

[0019] After all the lithium source solution is added, stirring, heating and vacuum treatment are continued to evaporate the halide mother liquor and the lithium source solution that are not involved in the co-precipitation. When all the halide mother liquor and the lithium source solution are evaporated, the co-precipitation product is crystallized.

[0020] In some optional embodiments, the chemical formula of the electrolyte material is Li a MX b, wherein M is one or more of Al, Ga, In, Sc, Y, and La, X is one or more of F, Cl, Br, and I, 0≤a≤10, 1≤b≤13.

[0021] In some optional embodiments, the lithium source is a halide containing lithium element, and the chemical formula of the lithium source is LiX.

[0022] In some optional embodiments, the chemical formula of the metal halide is MX3.

[0023] In some optional embodiments, the chelating agent is one or more of ammonia water, ammonium chloride, ethylene glycol, polyethylene glycol, polyacrylic acid, citric acid, and ethylenediaminetetraacetic acid.

[0024] In some optional embodiments, the acid solution is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, phosphoric acid, hydrofluoric acid, and citric acid.

[0025] In some optional embodiments, the stirring speed of the halide mother liquor is 100rpm-500rpm, the heating temperature is 60-100°C, the vacuum degree of the vacuum pumping is 0.01MPa-0.05MPa, and the rate at which the lithium source solution is slowly added to the halide mother liquor is 1mL / min-50mL / min.

[0026] In some optional embodiments, the temperature for low-temperature sintering the crystallized co-precipitation product is 120°C-300°C.

[0027] The wet chemical preparation method of the electrolyte material provided in the present application provides a halide mother solution and a lithium source solution; the lithium source solution is slowly added to the halide mother solution for coprecipitation to generate a coprecipitation product; and the halide mother solution and the lithium source solution that are not involved in the coprecipitation are evaporated to crystallize the coprecipitation product; the coprecipitation product that is crystallized is sintered at a low temperature to obtain an electrolyte material. By first adding the halide mother solution, and then slowly adding the lithium source solution during the evaporation and crystallization process, the evaporation crystallization is combined with the coprecipitation, which can effectively achieve uniform crystallization of each component and avoid segregation caused by different solubility; and by slowly adding the lithium source solution, the solution state during the evaporation process can be effectively changed, so that the solution repeatedly returns to an unsaturated state, so that the product crystal size is controllable. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 is a flow chart of a wet chemical preparation method of an electrolyte material according to an embodiment of the present invention;

[0030] Figure 2 is a structural diagram of a wet chemical preparation device for electrolyte materials according to an embodiment of the present invention;

[0031] Figure 3 This is a SEM image of the product Li3InCl6 obtained by the wet chemical preparation method of the electrolyte material proposed in one embodiment of the present invention;

[0032] Figure 4 This is an XRD diagram of the product Li3InCl6 obtained by the wet chemical preparation method of the electrolyte material proposed in one embodiment of the present invention;

[0033] Figure 5 This is an EIS graph of the product Li3InCl6 obtained by the wet chemical preparation method of the electrolyte material proposed in one embodiment of the present invention.

[0034] The following is a supplementary description of the attached drawings:

[0035] 1-evaporation crystallization kettle; 2-jacket; 3-baffle; 4-overflow port; 5-discharge port; 6-agitator; 7-feed port; 8-three-way solenoid valve; 9-diaphragm pump; 10-storage tank; 11-vacuum pump 11; 12-PLC control system. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] The term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present application. In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may include one or more of the features explicitly or implicitly. 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 the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0038] When a numerical range is disclosed herein, the above range is deemed to be continuous and includes the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise indicated, all ranges disclosed herein should be understood to include any and all sub-ranges included therein. For example, a specified range from "1 to 10" should be deemed to include any and all sub-ranges between a minimum of 1 and a maximum of 10. Exemplary sub-ranges of ranges 1 to 10 include, but are not limited to, 1 to 6.1, 3.5 to 7.8, 5.5 to 10, etc.

[0039] Since there is currently a lack of a wet chemical preparation method for electrolyte materials that can avoid partial segregation of multi-component compounds due to different solubilities during the crystallization process, avoid material hydrolysis due to pH changes, improve the purity of crystalline compounds, and make the crystal particle size controllable, therefore, in order to improve the purity of crystalline compounds and make the crystal particle size controllable, the present application provides a wet chemical preparation method for electrolyte materials.

[0040] See also Figure 1 , Figure 1 The present application provides a wet chemical preparation method for an electrolyte material, and the wet chemical preparation method for an electrolyte material comprises:

[0041] S101. Provide a halide mother solution and a lithium source solution.

[0042] In an optional embodiment, providing a halide mother solution and a lithium source solution comprises:

[0043] Dissolving a metal halide in distilled water to obtain a metal halide solution; dissolving a lithium source in distilled water to obtain a lithium source solution;

[0044] Dissolving the metal halide solution and the chelating agent to obtain a metal halide combined solution; dissolving the lithium source solution and the chelating agent to obtain a lithium source combined solution;

[0045] An acid solution is added to the metal halide combined solution to adjust the pH value to obtain a halide mother solution; and an acid solution is added to the lithium source combined solution to adjust the pH value to obtain a lithium source solution.

[0046] Optionally, the chemical formula of the metal halide is MX3, wherein M is one or more of Al, Ga, In, Sc, Y, and La, and X is one or more of F, Cl, Br, and I.

[0047] Optionally, the dissolution concentration of the metal halide can be set according to actual business needs, which is not limited here. Exemplarily, the dissolution concentration of the metal halide can be 10-200 g / L.

[0048] Optionally, the lithium source is a halide containing lithium element, and the chemical formula of the lithium source is LiX.

[0049] In an optional embodiment, the chelating agent is one or more of ammonia water, ammonium chloride, ethylene glycol, polyethylene glycol, polyacrylic acid, citric acid, and ethylenediaminetetraacetic acid.

[0050] Optionally, the concentration of the chelating agent can be set according to actual business needs, which is not limited here. Exemplarily, the concentration of the chelating agent can be 10-100 g / L.

[0051] In an optional embodiment, the acid solution is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, phosphoric acid, hydrofluoric acid, and citric acid.

[0052] Optionally, the pH values ​​of the halide mother solution and the lithium source solution are 3-7.

[0053] By adjusting the pH value of the halide mother liquor and the lithium source solution, the solution in the crystallization kettle is ensured to be always in an acidic state, which can avoid the hydrolysis of materials caused by pH changes during the evaporation and crystallization process and the generation of impurities.

[0054] S102. Slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product; and evaporating the halide mother solution and the lithium source solution that do not participate in the co-precipitation to crystallize the co-precipitation product.

[0055] Alternatively, the coprecipitation means that in a solution, when one substance forms a precipitate, other normally soluble substances are also brought into the precipitate and precipitate out of the solution together with the main precipitate.

[0056] Optionally, the crystallization refers to a process of reducing the volume of the solution by evaporating the halide mother solution and the lithium source solution, thereby increasing the concentration of the solute, and ultimately causing the coprecipitation product to exceed its solubility in the solvent and form crystals.

[0057] In an optional embodiment, the step of slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product; and evaporating the halide mother solution and the lithium source solution that do not participate in the co-precipitation to crystallize the co-precipitation product comprises:

[0058] Stirring, heating and vacuuming the halide mother liquor;

[0059] Slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product, wherein stirring, heating and vacuum treatment are maintained during the co-precipitation process;

[0060] While the coprecipitation is being carried out, evaporating the halide mother solution and the lithium source solution that are not involved in the coprecipitation;

[0061] After all the lithium source solution is added, stirring, heating and vacuum treatment are continued to evaporate the halide mother liquor and the lithium source solution that are not involved in the co-precipitation. When all the halide mother liquor and the lithium source solution are evaporated, the co-precipitation product is crystallized.

[0062] Optionally, the stirring speed for stirring the halide mother liquor can be set according to actual business needs, which is not limited here. Exemplarily, the stirring speed can be 100rpm-500rpm.

[0063] Optionally, the heating temperature may be set according to actual business needs, which is not limited here. Exemplarily, the heating temperature may be 60°C-100°C.

[0064] Optionally, the vacuum degree of the vacuum extraction can be set according to actual business needs, which is not limited here. Exemplarily, the vacuum degree of the vacuum extraction can be 0.01Mpa-0.05Mpa.

[0065] Optionally, the rate at which the lithium source solution is slowly added to the halide mother liquor can be set according to actual business needs, which is not limited here. Exemplarily, the rate at which the lithium source solution is slowly added to the halide mother liquor can be 1 mL / min-50 mL / min.

[0066] By first adding the halide mother liquor and then slowly adding the lithium source solution during the evaporation crystallization process, the evaporation crystallization and co-precipitation are combined, which can effectively achieve uniform crystallization of each component, avoid segregation caused by different solubilities, and improve the purity of the crystalline compound; and by slowly adding the lithium source solution, the state of the solution during the evaporation process can be effectively changed, allowing the solution to repeatedly return to an unsaturated state, so that the product crystal particle size can be controlled.

[0067] S103. The coprecipitated product is subjected to low-temperature sintering to obtain an electrolyte material.

[0068] In an optional embodiment, the chemical formula of the electrolyte material is Li a MX b , wherein M is one or more of Al, Ga, In, Sc, Y, and La, X is one or more of F, Cl, Br, and I, 0≤a≤10, 1≤b≤13.

[0069] Optionally, the electrolyte material may be one or more of Li3InCl6, Li3Ycl6, Li3Ybr6, Li3HoCl6, Li3ScCl6, etc.

[0070] Optionally, the temperature for low-temperature sintering the crystallized co-precipitation product can be set according to actual business needs, which is not limited here. For example, the temperature for low-temperature sintering the crystallized co-precipitation product can be 120°C-300°C.

[0071] Optionally, the time for low-temperature sintering the crystallized co-precipitated product can be set according to actual business needs, which is not limited here. Exemplarily, the time for low-temperature sintering can be 12 hours.

[0072] See also Figure 2 , Figure 2 It is a structural diagram of a wet chemical preparation device for electrolyte materials proposed according to an embodiment of the present invention. The wet chemical preparation device for electrolyte materials provided in the present application includes: an evaporation crystallization kettle 1, a jacket 2, a baffle 3, an overflow port 4, a discharge port 5, an agitator 6, a feed port 7, a three-way solenoid valve 8, a diaphragm pump 9, a storage tank 10, a vacuum pump 11 and a PLC control system 12.

[0073] The following is an overall description of the wet chemical preparation method of the electrolyte material in combination with the wet chemical preparation device of the electrolyte material:

[0074] Dissolving a metal halide in distilled water, adding a chelating agent, and adding an acid solution to adjust the pH value to obtain a halide mother solution; dissolving a lithium source in distilled water, adding a chelating agent, and adding an acid solution to adjust the pH value to obtain a lithium source solution;

[0075] The halide mother liquor is poured into the evaporation crystallization kettle 1, and the lithium source solution is poured into the storage tank 10. The evaporation crystallization kettle 1 is stirred, heated and vacuumed by the stirrer 6, and a certain vacuum degree is maintained;

[0076] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 to start crystallization;

[0077] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0078] The coprecipitated product was taken out, placed in a muffle furnace, and sintered at low temperature for 12 hours to obtain the final product electrolyte material.

[0079] In this solution, the lithium source solution is in a storage tank, and the evaporation and crystallization kettle contains the halide mother liquor, which can increase the amount of evaporation and crystallization in a single batch and improve production capacity.

[0080] Embodiment 1:

[0081] Raw materials used: LiCl, InCl3, distilled water, NH4Cl, hydrochloric acid solution; final product electrolyte material: Li3InCl6.

[0082] The specific preparation method is as follows:

[0083] Dissolve 110.59g InCl3 in 1L of distilled water, add 25g NH4Cl to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a halide mother solution; dissolve 63.5g LiCl in 1L of distilled water, add 25g NH4Cl to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a lithium source solution;

[0084] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 90°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.01Mpa, and maintain the vacuum degree;

[0085] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 5 ml / min, and crystallization begins;

[0086] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0087] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 150°C for 12 hours to obtain the final product electrolyte material Li3InCl6.

[0088] See also Figure 3 , Figure 3 This is a SEM image of the product Li3InCl6 obtained by the wet chemical preparation method of the electrolyte material proposed in one embodiment of the present invention. As can be seen from the figure, the shape of the prepared electrolyte material product Li3InCl6 is relatively regular.

[0089] See also Figure 4 , Figure 4 This is the XRD graph of the product Li3InCl6 obtained by the wet chemical preparation method of the electrolyte material proposed in one embodiment of the present invention. The horizontal coordinate 2θ of the XRD graph represents the X-ray diffraction angle, and the vertical coordinate represents the standard diffraction intensity, that is, the intensity of the X-ray after being diffracted by the crystal at the 2θ diffraction angle. The intensity of the diffraction peak can reflect the order of the atomic arrangement in the crystal and estimate the relative content in the sample. It can be seen from the figure that the prepared electrolyte material product is Li3InCl6, and no characteristic peaks of other impurities appear.

[0090] See also Figure 5 , Figure 5 This is an EIS graph of Li3InCl6, a product obtained by the wet chemical preparation method of the electrolyte material proposed in one embodiment of the present invention. The abscissa of the EIS graph represents the real part of the impedance, and the ordinate represents the imaginary part of the impedance, which reflects the ability to store and release charge in the electrochemical system. As can be seen from the figure, the ionic conductivity of the prepared electrolyte material product Li3InCl6 is 1.27mS / cm, indicating that the product prepared by the wet chemical preparation method of the electrolyte material proposed in the present invention has a higher ionic conductivity.

[0091] Embodiment 2:

[0092] Raw materials used: LiCl, InCl3, distilled water, NH4Cl, nitric acid solution; final product electrolyte material: Li3InCl6.

[0093] The specific preparation method is as follows:

[0094] Dissolve 44.2g InCl3 in 1L of distilled water, add 10g NH4Cl to dissolve, add nitric acid solution, adjust the pH value to 3, and obtain a halide mother solution; dissolve 25.4g LiCl in 1L of distilled water, add 10g NH4Cl to dissolve, add nitric acid solution, adjust the pH value to 3, and obtain a lithium source solution;

[0095] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 100 rpm, heat to 100 ° C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.05Mpa, and maintain the vacuum degree;

[0096] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 10ml / min, and crystallization begins;

[0097] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0098] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 120°C for 12 hours to obtain the final product electrolyte material Li3InCl6.

[0099] Embodiment 3:

[0100] Raw materials used: LiBr, Ybr3, distilled water, NH4Cl, hydrochloric acid solution; final product electrolyte material: Li3Ybr6.

[0101] The specific preparation method is as follows:

[0102] Dissolve 70.9g Ybr3 in 1L of distilled water, add 50g NH4Cl to dissolve, and add hydrochloric acid solution, adjust the pH value to 5 to obtain a halide mother solution; dissolve 52.1g LiBr in 1L of distilled water, add 50g NH4Cl to dissolve, and add hydrochloric acid solution, adjust the pH value to 5 to obtain a lithium source solution;

[0103] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 90°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.02Mpa, and maintain the vacuum degree;

[0104] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 20ml / min, and crystallization begins;

[0105] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0106] The co-precipitated product was taken out, placed in a muffle furnace, and sintered at 200°C for 12 hours to obtain the final product electrolyte material Li3Ybr6.

[0107] Embodiment 4:

[0108] Raw materials used: LiBr, Ybr3, distilled water, ethylene glycol, hydrochloric acid solution; final product electrolyte material: Li3Ybr6.

[0109] The specific preparation method is as follows:

[0110] Dissolve 141.8g Ybr3 in 1L of distilled water, add 25g ethylene glycol to dissolve, add hydrochloric acid solution, adjust the pH value to 6, and obtain a halide mother solution; dissolve 104.2g LiBr in 1L of distilled water, add 25g ethylene glycol to dissolve, add hydrochloric acid solution, adjust the pH value to 6, and obtain a lithium source solution;

[0111] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 500rpm, heat to 90°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.02Mpa, and maintain the vacuum degree;

[0112] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 50ml / min, and crystallization begins;

[0113] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0114] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 300°C for 12 hours to obtain the final product electrolyte material Li3Ybr6.

[0115] Embodiment 5:

[0116] Raw materials used: LiCl, YCl3, distilled water, NH4Cl, acetic acid solution; final product electrolyte material: Li3YCl6.

[0117] The specific preparation method is as follows:

[0118] Dissolve 97.8g YCl3 in 1L of distilled water, add 50g NH4Cl to dissolve, add acetic acid solution, adjust the pH value to 6, and obtain a halide mother solution; dissolve 63.6g LiCl in 1L of distilled water, add 50g NH4Cl to dissolve, add acetic acid solution, adjust the pH value to 6, and obtain a lithium source solution;

[0119] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 100°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.05Mpa, and maintain the vacuum degree;

[0120] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 10ml / min, and crystallization begins;

[0121] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0122] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 200°C for 12 hours to obtain the final product electrolyte material Li3YCl6.

[0123] Embodiment 6:

[0124] Raw materials used: LiCl, HoCl3, distilled water, NH4Cl, acetic acid solution; final product electrolyte material: Li3HoCl6.

[0125] The specific preparation method is as follows:

[0126] Dissolve 135.6 g HoCl3 in 1 L of distilled water, add 100 g NH4Cl to dissolve, add acetic acid solution, adjust the pH value to 3, and obtain a halide mother solution; dissolve 63.6 g LiCl in 1 L of distilled water, add 100 g NH4Cl to dissolve, add acetic acid solution, adjust the pH value to 3, and obtain a lithium source solution;

[0127] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 70°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.01Mpa, and maintain the vacuum degree;

[0128] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 10ml / min, and crystallization begins;

[0129] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0130] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 300°C for 12 hours to obtain the final product electrolyte material Li3HoCl6.

[0131] Embodiment 7:

[0132] Raw materials used: LiCl, ScCl3, distilled water, EDTA, sulfuric acid solution; final product electrolyte material: Li3ScCl6.

[0133] The specific preparation method is as follows:

[0134] Dissolve 75.7g ScCl3 in 1L of distilled water, add 50g EDTA to dissolve, add sulfuric acid solution, adjust the pH value to 4, and obtain a halide mother solution; dissolve 63.6g LiCl in 1L of distilled water, add 50g EDTA to dissolve, add sulfuric acid solution, adjust the pH value to 4, and obtain a lithium source solution;

[0135] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 300rpm, heat to 80°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.02Mpa, and maintain the vacuum degree;

[0136] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 30ml / min, and crystallization begins;

[0137] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0138] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 150°C for 12 hours to obtain the final product electrolyte material Li3ScCl6.

[0139] Embodiment 8:

[0140] Raw materials used: LiCl, InCl3, ScCl3, distilled water, citric acid, hydrochloric acid solution; final product electrolyte material: Li3In 0.5 Sc 0.5 Cl6.

[0141] The specific preparation method is as follows:

[0142] Dissolve 55.3 g InCl3 and 37.8 g ScCl3 in 1 L of distilled water, add 50 g citric acid to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a halide mother solution; dissolve 63.6 g LiCl in 1 L of distilled water, add 50 g citric acid to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a lithium source solution;

[0143] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 90°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.01Mpa, and maintain the vacuum degree;

[0144] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 10ml / min, and crystallization begins;

[0145] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0146] The coprecipitated product was taken out and placed in a muffle furnace, and sintered at 200°C for 12 hours to obtain the final electrolyte material Li3In 0.5 Sc 0.5 Cl6.

[0147] Embodiment 9:

[0148] Raw materials used: LiBr, YBr3, AlBr3, distilled water, polyethylene glycol, hydrochloric acid solution; final product electrolyte material: Li3Y 0.8 Al 0.2 Br6.

[0149] The specific preparation method is as follows:

[0150] Dissolve 56.7g YBr3 and 10.7g AlBr3 in 1L of distilled water, add 50g polyethylene glycol to dissolve, add hydrochloric acid solution, adjust the pH value to 3, and obtain a halide mother solution; dissolve 52.1g LiBr in 1L of distilled water, add 50g polyethylene glycol to dissolve, add hydrochloric acid solution, adjust the pH value to 3, and obtain a lithium source solution;

[0151] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 300rpm, heat to 90°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.01Mpa, and maintain the vacuum degree;

[0152] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 20ml / min, and crystallization begins;

[0153] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0154] The coprecipitated product was taken out, placed in a muffle furnace, and sintered at 200°C for 12 hours to obtain the final product electrolyte material Li3Y 0.8 Al 0.2 Br6.

[0155] Embodiment 10:

[0156] Raw materials used: LiCl, LiBr, InCl3, distilled water, polyacrylic acid, hydrochloric acid solution; final product electrolyte material: Li3InCl5Br.

[0157] The specific preparation method is as follows:

[0158] Dissolve 110.6g of InCl3 in 1L of distilled water, add 50g of polyacrylic acid to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a halide mother solution; dissolve 42.4g of LiCl and 42.4g of LiBr in 1L of distilled water, add 50g of polyacrylic acid to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a lithium source solution;

[0159] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 90°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.01Mpa, and maintain the vacuum degree;

[0160] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 20ml / min, and crystallization begins;

[0161] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0162] The coprecipitated product was taken out, put into a muffle furnace, and sintered at 150°C for 12 hours to obtain the final product electrolyte material Li3InCl5Br.

[0163] Embodiment 11:

[0164] Raw materials used: LiCl, LiBr, YBr3, distilled water, polyacrylic acid, hydrochloric acid solution; final product electrolyte material: Li3YClBr5.

[0165] The specific preparation method is as follows:

[0166] Dissolve 70.9g YBr3 in 1L of distilled water, add 20g polyacrylic acid to dissolve, add hydrochloric acid solution, adjust the pH value to 5, and obtain a halide mother solution; dissolve 8.5g LiCl and 34.7g LiBr in 1L of distilled water, add 20g polyacrylic acid to dissolve, add hydrochloric acid solution, adjust the pH value to 5, and obtain a lithium source solution;

[0167] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 90°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.02Mpa, and maintain the vacuum degree;

[0168] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 20ml / min, and crystallization begins;

[0169] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0170] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 200°C for 12 hours to obtain the final product electrolyte material Li3YClBr5.

[0171] Embodiment 12:

[0172] Raw materials used: LiBr, ScCl3, distilled water, ethylene glycol, sulfuric acid solution; final product electrolyte material: Li3ScCl3Br3.

[0173] The specific preparation method is as follows:

[0174] Dissolve 75.7gScCl3 in 1L of distilled water, add 20g of ethylene glycol to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a halide mother solution; dissolve 130.3gLiBr in 1L of distilled water, add 20g of ethylene glycol to dissolve, add hydrochloric acid solution, adjust the pH value to 4, and obtain a lithium source solution;

[0175] Pour the halide mother liquor into the evaporation crystallization kettle 1, pour the lithium source solution into the storage tank 10, start stirring the evaporation crystallization kettle 1 through the stirrer 6, the speed is 200rpm, heat to 80°C, turn on the vacuum pump 11 to start vacuuming the evaporation crystallization kettle 1 to 0.02Mpa, and maintain the vacuum degree;

[0176] After the temperature and vacuum degree in the evaporation crystallization kettle 1 reach the target values, the diaphragm pump 9 is turned on, and the lithium source solution in the storage tank 10 is slowly added to the evaporation crystallization kettle 1 through the diaphragm pump 9, and the feeding rate is 20ml / min, and crystallization begins;

[0177] After the lithium source solution in the storage tank 10 is added, stirring, heating and vacuuming are continued to evaporate the halide mother solution and the lithium source solution that are not involved in the coprecipitation until the solution is completely evaporated and the coprecipitation product is crystallized;

[0178] The co-precipitated product was taken out, put into a muffle furnace, and sintered at 200°C for 12 hours to obtain the final product electrolyte material Li3ScCl3Br3.

[0179] Please refer to Table 1, which shows the ionic conductivity of the products obtained by the wet chemical preparation method of the electrolyte material proposed in the embodiment of the present invention. It can be seen from the data in the table that the electrolyte materials prepared by the wet chemical preparation method of the electrolyte material proposed in the present invention all have higher ionic conductivity.

[0180] Table 1

[0181]

[0182]

[0183] The wet chemical preparation method of the electrolyte material provided in the present application comprises providing a halide mother solution and a lithium source solution; slowly adding the lithium source solution to the halide mother solution for coprecipitation to generate a coprecipitation product; evaporating the halide mother solution and the lithium source solution that do not participate in the coprecipitation to crystallize the coprecipitation product; and low-temperature sintering the crystallized coprecipitation product to obtain the electrolyte material. The wet chemical preparation method of the electrolyte material provided in the present application has the following beneficial effects:

[0184] (1) By first adding the halide mother solution and then slowly adding the lithium source solution during the evaporation crystallization process, the evaporation crystallization and coprecipitation are combined to effectively achieve uniform crystallization of each component, avoid segregation caused by different solubility, and improve the purity of the crystalline compound;

[0185] (2) adjusting the pH values ​​of the halide mother solution and the lithium source solution to ensure that the solution in the crystallization kettle is always in an acidic state, thereby avoiding the hydrolysis of the material caused by pH changes during the evaporation and crystallization process and generating impurities;

[0186] (3) By slowly adding the lithium source solution, the state of the solution during the evaporation process can be effectively changed, allowing the solution to repeatedly return to an unsaturated state, making the product crystal size controllable;

[0187] (4) The lithium source solution is in a storage tank, and the evaporation and crystallization kettle contains the halide mother liquor, which increases the amount of evaporation and crystallization in a single batch and improves production capacity.

[0188] The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A wet chemical preparation method of an electrolyte material, characterized in that: The wet chemical preparation method of the electrolyte material comprises: Providing halide mother solution and lithium source solution; Slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product; and evaporating the halide mother solution and the lithium source solution that do not participate in the co-precipitation to crystallize the co-precipitation product; The crystallized coprecipitation product is subjected to low temperature sintering to obtain an electrolyte material.

2. The wet chemical preparation method of the electrolyte material according to claim 1, characterized in that: The provision of halide mother solution and lithium source solution comprises: Dissolving a metal halide in distilled water to obtain a metal halide solution; dissolving a lithium source in distilled water to obtain a lithium source solution; Dissolving the metal halide solution and the chelating agent to obtain a metal halide combined solution; dissolving the lithium source solution and the chelating agent to obtain a lithium source combined solution; An acid solution is added to the metal halide combined solution to adjust the pH value to obtain a halide mother solution; and an acid solution is added to the lithium source combined solution to adjust the pH value to obtain a lithium source solution.

3. The wet chemical preparation method of the electrolyte material according to claim 1, characterized in that: Slowly adding the lithium source solution into the halide mother solution to perform co-precipitation to generate a co-precipitation product; and evaporating the halide mother solution and the lithium source solution that are not involved in the coprecipitation to crystallize the coprecipitation product, comprising: Stirring, heating and vacuuming the halide mother liquor; Slowly adding the lithium source solution to the halide mother solution for co-precipitation to generate a co-precipitation product, wherein stirring, heating and vacuum treatment are maintained during the co-precipitation process; While the coprecipitation is being carried out, evaporating the halide mother solution and the lithium source solution that are not involved in the coprecipitation; When the halide mother solution and the lithium source solution are completely evaporated, the coprecipitated product is crystallized.

4. The wet chemical preparation method of the electrolyte material according to claim 1, characterized in that: The chemical formula of the electrolyte material is LiaMXb, wherein M is one or more of Al, Ga, In, Sc, Y, and La, X is one or more of F, Cl, Br, and I, and 0≤a≤10, 1≤b≤13.

5. The wet chemical preparation method of the electrolyte material according to claim 4, characterized in that: The lithium source is a halide containing lithium element, and the chemical formula of the lithium source is LiX.

6. The wet chemical preparation method of the electrolyte material according to claim 5, characterized in that: The chemical formula of the metal halide is MX3.

7. The wet chemical preparation method of the electrolyte material according to claim 2, characterized in that: The chelating agent is one or more of ammonia water, ammonium chloride, ethylene glycol, polyethylene glycol, polyacrylic acid, citric acid, and ethylenediaminetetraacetic acid.

8. The wet chemical preparation method of electrolyte material according to claim 2, characterized in that: The acid solution is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, phosphoric acid, hydrofluoric acid, and citric acid.

9. The wet chemical preparation method of the electrolyte material according to claim 3, characterized in that: The stirring speed of the halide mother liquor is 100rpm-500rpm, the heating temperature is 60°C-100°C, the vacuum degree of the vacuum pumping is 0.01MPa-0.05MPa, and the rate of slowly adding the lithium source solution to the halide mother liquor is 1mL / min-50mL / min.

10. The wet chemical preparation method of electrolyte material according to claim 1, characterized in that: The temperature for low-temperature sintering the crystallized coprecipitation product is 120°C-300°C.

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