Fast ion conductor nanometer lithium metaaluminate material and preparation method thereof
The preparation of nano lithium aluminate materials through wet chemistry has solved the problems of complex preparation processes, high energy consumption and poor product purity in the existing technology, and achieved high purity and narrow particle size distribution. It is suitable for industrial production and significantly improved the performance of the battery.
Patent Information
- Application Number
- CN202510228415.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-28
- Publication Date
- 2025-05-06
AI Technical Summary
The existing preparation methods of lithium aluminate materials have problems such as complex processes, high energy consumption, poor product purity and low yield, which are difficult to meet the needs of industrial production.
Using a simplified wet chemistry method, the pH value is controlled to 6-8 by combining the aqueous solution of the lithium source and the powder of the aluminum source, and the water is evaporated to dryness with heating and stirring to obtain a lithium-aluminum composite precursor, and a nano-scale lithium aluminate material is obtained by calcination.
The preparation of nano-lithium aluminate materials with high purity and narrow particle size distribution is achieved. The process is simple and the cost is low, and it is suitable for large-scale industrial production, which significantly improves the cycle stability and performance of the battery.
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Figure CN119943960A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of lithium ion battery materials, and in particular, relates to a fast ion conductor nano lithium aluminate material and a preparation method thereof. Background Art
[0002] Lithium aluminate (LiAlO2) is a fast ion conductor with good thermal stability, chemical stability and mechanical properties, so it has been widely used in the field of lithium-ion battery materials. In particular, lithium aluminate has significant advantages as an electrolyte skeleton material, polymer electrolyte additive and coating layer of electrode materials. When it is used as a surface coating layer of a ternary positive electrode active material, it can effectively increase the migration rate of lithium ions between the electrode and the electrolyte interface. In addition, due to the presence of the lithium aluminate coating layer, it can inhibit the corrosion of the ternary material by hydrogen fluoride (HF) generated during the decomposition of the electrolyte, reduce the decomposition of the positive electrode active material, and thus make the material's cycle performance better than that of the uncoated material. Due to these excellent properties, lithium aluminate has broad application prospects in lithium-ion batteries as a fast ion conductor.
[0003] However, the existing preparation methods of lithium aluminate materials have some shortcomings. Traditional synthesis methods, such as solid phase reaction method, combustion synthesis method, molten salt reaction method, sol-gel method and hydrothermal synthesis method, all have certain defects. Specifically:
[0004] Solid phase reaction method: Although this method is simple, it usually requires a long time of high temperature reaction, which makes it more energy consuming. Impurities are easily introduced during the reaction process, resulting in low purity of the product, low yield, and poor sintering performance. Combustion synthesis method: Combustion synthesis method uses the heat released by the chemical reaction of metal salts and organic fuels to complete the preparation process. Although it does not require a calcination step, the low purity of the product and the large number of by-products affect the quality of the final material. Molten salt reaction method: This method has high equipment cost and high energy consumption, and the impurities in the sintered materials are not completely removed, which affects the purity and yield of the product; Sol-gel method: The sol-gel method has the advantages of easy blending of raw materials, high product purity, and low required temperature, but it is difficult to control the morphology of the synthesized substances, and the reaction process is complicated, the cost is high, and the particle size of the product is large. The preparation process takes a long time and is prone to produce by-products, which has high requirements for equipment; Hydrothermal synthesis method: The hydrothermal synthesis method is relatively simple in operation and easy to control the product morphology, but the control of process parameters is more difficult and has high requirements on equipment.
[0005] In summary, although the existing preparation methods have their own advantages, they generally have problems such as complex process, high energy consumption, poor product purity, and low yield, which are difficult to meet the needs of industrial production. Therefore, there is an urgent need for a new preparation method that can simplify the process, reduce costs, and improve the purity and yield of the product, and at the same time, can produce lithium aluminate materials with narrow particle size distribution and excellent performance, providing reliable technical support for large-scale applications. Summary of the invention
[0006] The first technical problem to be solved by the present invention is to provide a method for preparing fast ion conductor nano lithium aluminate material to solve the problems of large product particle size, complex preparation process, low yield and high equipment requirements in the conventional preparation method in the prior art.
[0007] In order to overcome the defects of the above prior art (or related art), the present invention provides a method for preparing a fast ion conductor nano lithium aluminate material, comprising the following steps: S1: weigh a lithium source according to the stoichiometric ratio of LiAlO2 and dissolve it in water, heat and stir to dissolve it, and obtain a lithium source aqueous solution; Weighing an aluminum source according to the stoichiometric ratio of LiAlO2 and adding it to the solution of step S1, adjusting the pH to 6-8, heating and stirring the solution to evaporate the water to obtain a lithium-aluminum composite precursor; S2: crushing and calcining the lithium-aluminum composite precursor obtained in step S1 to obtain the nano lithium aluminate material.
[0008] Compared with the prior art, the preparation method of a fast ion conductor nano lithium aluminate material of the present invention has the following advantages: the preparation method of the present invention changes the complex synthesis steps in the prior art (such as high-temperature solid-phase method, molten salt reaction method, etc.) into a simplified wet chemical method, adopts a lithium source aqueous solution combined with aluminum source powder dispersion, and through precise control of pH value, lithium ions are uniformly infiltrated and coated with aluminum source powder, and finally a nano-scale lithium aluminate material with a small particle size and uniform distribution is obtained by calcination. The core advantages of the preparation method of the present invention are high product purity, good particle size control, and can ensure high yield and narrow particle size distribution during the production process. In addition, the preparation method of the present invention has the characteristics of simple process, low cost, low equipment requirements, etc., and is particularly suitable for large-scale industrial production. Through the method of the present invention, the problems of low yield, uneven particle size, poor purity, and high equipment requirements of the existing preparation method mentioned in the background technology are solved, ensuring the application effect of the prepared nano lithium aluminate material in lithium ion batteries, and can significantly improve the cycle stability and performance of the battery, which is specifically reflected in the material's rapid ionic conductivity and good adaptability to electrolytes and electrodes. The prepared material is suitable for use as a coating layer for high-efficiency battery materials, thereby further improving the overall efficiency and life of the battery.
[0009] In a possible embodiment, in step S1, the lithium source is selected from at least one of lithium oxide, anhydrous lithium hydroxide, lithium hydroxide monohydrate, lithium nitrate, lithium formate, lithium acetate, lithium oxalate, and lithium citrate; the aluminum source is selected from at least one of anhydrous aluminum nitrate, aluminum nitrate nonahydrate, aluminum acetate, aluminum isopropoxide, boehmite, pseudo-boehmite, aluminum oxide, and aluminum hydroxide.
[0010] Compared with the prior art, the above technical scheme is adopted to optimize the reaction conditions and product properties in the preparation process by selecting different lithium sources and aluminum sources. For example, the selection of a water-soluble or easily soluble lithium source (such as lithium nitrate, lithium citrate) is conducive to rapid dissolution in the solution, so that lithium ions can fully penetrate into the surface or interior of the aluminum source particles, and then evenly coat the aluminum source particles; and the use of different types of aluminum sources (such as aluminum hydroxide, pseudo-boehmite, etc.) can provide different aluminum source forms. These aluminum sources have different solubility, reactivity and ion migration capabilities in chemical reactions, thereby affecting the crystal form, particle size, purity and structural stability of the final product; and finally, a nano lithium aluminate material with uniform particle size, high purity and good electrical conductivity is prepared.
[0011] In a possible implementation, in step S1, the lithium source is at least one of lithium hydroxide monohydrate, lithium nitrate, and lithium acetate; and the aluminum source is at least one of pseudo-boehmite or aluminum hydroxide.
[0012] Compared with the prior art, the above technical scheme is adopted to further optimize the lithium source and the aluminum source. Lithium hydroxide monohydrate, lithium nitrate and lithium acetate as lithium sources have good solubility and reactivity, which makes it easier for lithium ions to undergo uniform chemical reaction with the aluminum source in aqueous solution. Pseudoboehmite and aluminum hydroxide as aluminum sources have good chemical reactivity and high solubility, and can be easily combined with the lithium source to form a uniform lithium-aluminum composite precursor, and finally prepare nano lithium aluminate material with small particle size, high purity and uniform morphology.
[0013] In a possible implementation, in step S1, in the lithium source aqueous solution, the mass ratio of lithium source to water is (2-4):1, and the heating and stirring temperature of the lithium source aqueous solution is 25-100°C.
[0014] Compared with the prior art, the above technical solution is adopted to reasonably adjust the mass ratio of lithium source to water to (2-4):1, so that the solubility of lithium source in water is significantly improved, so that lithium ions can quickly and evenly enter the solution, providing a better raw material basis for subsequent reactions. At the same time, the appropriate amount of water not only avoids the phenomenon of excessive concentration of lithium source, but also prevents the solution from being too thin, maintaining a suitable ion concentration; and the stirring temperature is controlled at 25-100°C, the lithium source can be quickly dissolved, and the temperature is relatively low, which helps to better control the reaction process and avoid side reactions or impurity generation caused by high temperature. In addition, within this temperature range, the water evaporation rate is relatively moderate, which can ensure the full reaction of lithium source and water, and does not require excessively high temperature, thereby reducing energy consumption and improving the efficiency of the production process.
[0015] In a possible implementation, in step S1, the pH is adjusted by adding 2-8 M acetic acid or citric acid solution to adjust the pH, and heating and stirring the solution to evaporate the water to a temperature of 25-120°C.
[0016] Compared with the prior art, the above technical solution is adopted to optimize the solubility of the lithium source and the aluminum source in the reaction system by adding 2-8 M acetic acid or citric acid solution to adjust the pH to 6-8. The pH range is the best reaction environment between lithium ions and the aluminum source, which helps to reduce the like charge effect on the surface of the aluminum source particles, so that lithium ions can be more easily adsorbed on the surface of the aluminum source particles, thereby promoting the uniform formation of the lithium-aluminum composite precursor. The temperature is controlled within the range of 25-120° C., so that the water evaporates moderately, which can ensure that the water in the solution is evaporated without causing excessive temperature to damage the structure of the reactants. Through the further restrictions of the above implementation mode, the reaction uniformity of the lithium source and the aluminum source can be improved, and the nano lithium aluminate material finally obtained has higher purity, narrower particle size distribution, and better electrochemical performance.
[0017] In a possible implementation, in step S2, the calcination conditions include: a heating rate of 2-10° C. / min, a calcination temperature of 700-900° C., and a holding time of 2-10 h.
[0018] Compared with the prior art, the above-mentioned technical scheme controls a slower heating rate (2-10 ℃ / min) so that the reactants can fully react during the calcination process, avoiding incomplete reaction or excessive sintering of the material surface caused by a sudden temperature rise. At a calcination temperature of 700-900 ℃, the lithium source and the aluminum source can effectively react to form a high-purity γ-LiAlO2 phase, while avoiding the generation of impurities that may be caused by excessively high temperatures. Furthermore, the holding time is controlled to be 2-10 h, which controls the particle size and crystal stability. Too short a holding time may cause part of the aluminum source to not react completely, while too long a holding time may cause excessive growth of the crystal particles or irregular crystal morphology.
[0019] The second technical problem to be solved by the present invention is to provide a fast ion conductor nano lithium aluminate material to solve the problems of large particle size, poor conductivity, poor cycle stability and complex synthesis process of conventional lithium aluminate materials in the prior art.
[0020] In order to overcome the above defects of the prior art, the present invention provides a fast ion conductor nano lithium aluminate material, and the fast ion conductor nano lithium aluminate material is prepared by the above preparation method.
[0021] Compared with the prior art, the fast ion conductor nano lithium aluminate material of the present invention solves the problems of large particle size and poor cycle stability of traditional lithium aluminate materials. The obtained material not only has better electrochemical properties, especially better application effect in lithium ion batteries, but also has the significant advantages of low cost, simple process and high yield:
[0022] Uniform particle size and narrow distribution: Compared with traditional synthesis methods, such as solid phase method or high temperature sintering method, the lithium aluminate material of the present invention can more accurately control the particle size range (60-120 nm), avoiding the generation of larger particle size or uneven particles; High purity: The lithium aluminate material of the present invention avoids the introduction of impurities by reasonably controlling the pH value, heating and stirring conditions, and calcination temperature in the preparation method, and the final obtained lithium aluminate material has high purity and no by-products; Excellent ionic conductivity and cycle stability: Due to the small and uniform particle size of the material, it can provide more active sites and improve the migration rate of lithium ions, thereby improving the conductivity and cycle stability of the material, which is particularly suitable for battery electrolytes and electrode materials.
[0023] In a possible implementation manner, the lithium aluminate is γ-LiAlO2, and the particle size of the nano lithium aluminate material is 60 to 120 nm.
[0024] Compared with the prior art, the above technical solution can significantly improve the performance and application effect of the material by controlling the crystal form and particle size range of lithium aluminate. In particular, by preparing the γ-LiAlO2 phase, it can ensure that the material has better ionic conductivity and higher stability, while ensuring that the particle size range is between 60-120 nm, so that the nano lithium aluminate material of the present invention has excellent ionic conductivity and stable electrochemical properties, and is particularly suitable for the application of lithium ion batteries and other energy storage devices. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Figure 1 This is a scanning electron microscope (SEM) image of the nano lithium aluminate prepared in Example 1; Figure 2 The X-ray diffraction (XRD) pattern of the nano lithium aluminate prepared in Example 1; Figure 3 This is a scanning electron microscope (SEM) image of the nano lithium aluminate prepared in Example 2; Figure 4 This is the X-ray diffraction (XRD) spectrum of the nano-lithium aluminate prepared in Example 2. DETAILED DESCRIPTION
[0026] First, those skilled in the art should understand that these implementations are only used to explain the technical principles of the embodiments of the present application, and are not intended to limit the protection scope of the embodiments of the present application. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.
[0027] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.
[0028] The present invention provides a method for preparing a fast ion conductor nano lithium aluminate material, comprising the following steps: S1: weigh a lithium source according to the stoichiometric ratio of LiAlO2 and dissolve it in water, heat and stir to dissolve it, and obtain a lithium source aqueous solution; Weighing an aluminum source according to the stoichiometric ratio of LiAlO2 and adding it to the solution of step S1, adjusting the pH to 6-8, heating and stirring the solution to evaporate the water to obtain a lithium-aluminum composite precursor; S2: crushing and calcining the lithium-aluminum composite precursor obtained in step S1 to obtain the nano lithium aluminate material.
[0029] As a preferred embodiment, in step S1, the lithium source is selected from at least one of lithium oxide, anhydrous lithium hydroxide, lithium hydroxide monohydrate, lithium nitrate, lithium formate, lithium acetate, lithium oxalate, and lithium citrate; the aluminum source is selected from at least one of anhydrous aluminum nitrate, aluminum nitrate nonahydrate, aluminum acetate, aluminum isopropoxide, boehmite, pseudo-boehmite, aluminum oxide, and aluminum hydroxide.
[0030] As a preferred solution, in step S1, the lithium source is at least one of lithium hydroxide monohydrate, lithium nitrate, and lithium acetate; and the aluminum source is at least one of pseudo-boehmite or aluminum hydroxide.
[0031] As a preferred solution, in step S1, the mass ratio of lithium source to water in the lithium source aqueous solution is (2-4):1, and the heating and stirring temperature of the lithium source aqueous solution is 25-100°C.
[0032] As a preferred solution, in step S1, the pH is adjusted by adding 2-8 M acetic acid or citric acid solution to adjust the pH, and heating and stirring the solution to evaporate the water to a temperature of 25-120°C.
[0033] As a preferred solution, in step S2, the calcination conditions include: a heating rate of 2-10°C / min, a calcination temperature of 700-900°C, and a holding time of 2-10 h.
[0034] The above-mentioned preparation method of the present invention, in general, is to disperse the aluminum source powder in the aqueous solution of lithium salt by a simple wet chemical method, and in the process of water evaporation, the lithium salt molecules are allowed to penetrate into the gaps of the aluminum source powder particles to form a uniform coating layer, and finally obtain a lithium-aluminum precursor uniformly coated with lithium salt. By adjusting the pH to about neutral, the like charges on the surface of the aluminum source powder particles are weakened, so that the lithium ions are better adsorbed on the surface of the aluminum source particles, thereby forming a uniform coating layer, so that a phase-pure lithium aluminate material is obtained after subsequent sintering, and the lithium source is mixed with the aluminum source in molecular form, which ensures the uniformity of the mixing and is also conducive to controlling the nano-sized lithium aluminate material. The preparation method of the present invention is simple in process, easy to operate, and low in cost. The obtained product has high purity, high yield, and narrow particle size distribution, and is particularly suitable for industrial production.
[0035] The present invention also provides a fast ion conductor nano lithium aluminate material, and the fast ion conductor nano lithium aluminate material is prepared by the above preparation method.
[0036] As a preferred solution, the lithium aluminate is γ-LiAlO2, and the particle size of the nano lithium aluminate material is 60-120 nm.
[0037] The γ phase of lithium aluminate has high ionic conductivity and good structural stability, especially in the application of lithium ion batteries, it can effectively improve the migration rate of lithium ions. By controlling the synthesis conditions, such as the appropriate heating rate and calcination temperature, the present invention can obtain a γ-LiAlO2 phase with high purity and stable structure, avoiding the formation of other low-conductivity phases, and controlling the particle size of the material within the range of 60-120 nm, which can significantly increase its specific surface area and provide more active sites for the insertion and extraction of lithium ions. Nanoscale particles can effectively increase the ion transfer rate, thereby enhancing the electrical conductivity of the material.
[0038] The following provides specific embodiments in combination with the above data range to further illustrate the content of the present invention: Example 1 This embodiment provides a fast ion conductor nano lithium aluminate material and a preparation method thereof. The fast ion conductor nano lithium aluminate material is prepared by the preparation method, which specifically includes the following steps: S1. Weigh 418.2 g of lithium hydroxide monohydrate according to the stoichiometric ratio of LiAlO2, add 1300 g of deionized water, heat and stir at 80°C to dissolve the lithium hydroxide, and obtain a lithium hydroxide aqueous solution; According to the stoichiometric ratio of LiAlO2, 677.6 g of pseudo-boehmite (with an aluminum oxide content of 75.25%) was weighed and slowly added to the aqueous solution of step S1, and the pH was adjusted to 7.2 with 4 M acetic acid solution, and then the slurry was heated and stirred at 110 ° C to evaporate the water to obtain a lithium-aluminum composite precursor block; S2. The lithium-aluminum composite precursor obtained in step S1 is crushed and then calcined at a temperature of 800° C., a heating rate of 5° C. / min, and a holding time of 10 h to obtain the nano lithium aluminate material.
[0039] like Figure 1-Figure 2 As shown, Figure 1 This is a SEM image of the nano lithium aluminate material prepared in Example 1. It can be seen from the figure that the nano lithium aluminate material particles are closely arranged and the particle size is relatively uniform, with an average particle size of about 110 nm; Figure 2 This is the XRD spectrum of the nano lithium aluminate prepared in Example 1. It can be seen from the figure that the diffraction peak position of the sample is consistent with the standard card of γ-LiAlO2, indicating that the nano lithium aluminate synthesized by the present invention has a structure of γ-LiAlO2 and has no diffraction peaks of other substances, indicating that the sample has high purity and is free of impurities.
[0040] Example 2 This embodiment provides a fast ion conductor nano lithium aluminate material and a preparation method thereof. The fast ion conductor nano lithium aluminate material is prepared by the preparation method, which specifically includes the following steps: S1. Weigh 418.2 g of lithium hydroxide monohydrate according to the stoichiometric ratio of LiAlO2, add 1350 g of deionized water, heat and stir at 90°C to dissolve the lithium hydroxide, and obtain a lithium hydroxide aqueous solution; 780 g of aluminum hydroxide was weighed according to the stoichiometric ratio of LiAlO2 and slowly added to the aqueous solution of step S1, and the pH was adjusted to 6.8 with 6 M acetic acid solution, and then the slurry was heated and stirred at 120 ° C to evaporate the water to obtain a lithium-aluminum composite precursor block; S2. The lithium-aluminum composite precursor obtained in step S1 is crushed and then calcined at a temperature of 750° C., a heating rate of 5° C. / min, and a holding time of 10 h to obtain the nano lithium aluminate material.
[0041] like Figure 3-Figure 4 As shown, Figure 3 This is a SEM image of the nano lithium aluminate material prepared in Example 2. It can be seen from the figure that the nano lithium aluminate material particles are closely arranged and the particle size is relatively uniform, with an average particle size of about 80 nm; Figure 4 This is the XRD spectrum of the nano lithium aluminate prepared in Example 2. It can be seen from the figure that the diffraction peak position of the sample is consistent with the standard card of γ-LiAlO2, indicating that the nano lithium aluminate synthesized by the present invention has a structure of γ-LiAlO2 and has no diffraction peaks of other substances, indicating that the sample has high purity and is free of impurities.
[0042] Embodiment 3: This embodiment provides a fast ion conductor nano lithium aluminate material and a preparation method thereof. The fast ion conductor nano lithium aluminate material is prepared by the preparation method, which specifically includes the following steps: S1. Weigh 659.9 g of lithium acetate according to the stoichiometric ratio of LiAlO2, add 1100 g of deionized water, heat and stir at 80°C to dissolve lithium hydroxide, and obtain a lithium hydroxide aqueous solution; According to the stoichiometric ratio of LiAlO2, 677.6 g of pseudo-boehmite (with an aluminum oxide content of 75.25%) was weighed and slowly added to the aqueous solution of step S1, and the pH was adjusted to 6.8 with 4 M acetic acid solution, and then the slurry was heated and stirred at 120 ° C to evaporate the water to obtain a lithium-aluminum composite precursor block; S2. The lithium-aluminum composite precursor obtained in step S1 is crushed and then calcined at a temperature of 800° C., a heating rate of 5° C. / min, and a holding time of 5 h to obtain the nano lithium aluminate material.
[0043] Through the above-mentioned Examples 1-3, it is further proved that the lithium aluminate prepared by the preparation method of the present invention is γ-LiAlO2, and its particle size is 60-120nm. The method of the present invention first prepares an aqueous solution of a soluble lithium source, and then disperses the aluminum source powder therein, and while heating and stirring to evaporate the water, the lithium source molecules penetrate into the particles of the aluminum source powder to obtain a lithium-aluminum composite precursor block uniformly coated with the lithium source molecules, and finally the lithium-aluminum precursor is calcined to obtain a nano-scale lithium aluminate material. Compared with the existing method for preparing lithium aluminate materials, the lithium aluminate prepared by the present invention has the advantages of low cost, simple process, pure product, high yield, narrow particle size distribution, etc., and is suitable for mass production, which provides a new idea for the nano-preparation of lithium aluminate materials.
[0044] In the description of the present application, the description with reference to the terms "one embodiment", "some embodiments", "in the present embodiment", "specific example", or "some examples" etc. means that the specific features, mechanisms, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0045] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.
Claims
1. A method for preparing a fast ion conductor nano lithium aluminate material, characterized in that: The following steps are involved: S1: weigh a lithium source according to the stoichiometric ratio of LiAlO2 and dissolve it in water, heat and stir to dissolve it, and obtain a lithium source aqueous solution; Weighing an aluminum source according to the stoichiometric ratio of LiAlO2 and adding it to the solution of step S1, adjusting the pH to 6-8, heating and stirring the solution to evaporate the water to obtain a lithium-aluminum composite precursor; S2: crushing and calcining the lithium-aluminum composite precursor obtained in step S1 to obtain the nano lithium aluminate material.
2. The method for preparing the fast ion conductor nano lithium aluminate material according to claim 1, characterized in that: In step S1, the lithium source is selected from at least one of lithium oxide, anhydrous lithium hydroxide, lithium hydroxide monohydrate, lithium nitrate, lithium formate, lithium acetate, lithium oxalate, and lithium citrate; the aluminum source is selected from at least one of anhydrous aluminum nitrate, aluminum nitrate nonahydrate, aluminum acetate, aluminum isopropoxide, boehmite, pseudo-boehmite, aluminum oxide, and aluminum hydroxide.
3. The method for preparing the fast ion conductor nano lithium aluminate material according to claim 2, characterized in that: In the step S1, the lithium source is at least one of lithium hydroxide monohydrate, lithium nitrate, and lithium acetate; and the aluminum source is at least one of pseudo-boehmite or aluminum hydroxide.
4. The method for preparing the fast ion conductor nano lithium aluminate material according to claim 1, characterized in that: In the step S1, the mass ratio of lithium source to water in the lithium source aqueous solution is (2-4):1, and the heating and stirring temperature of the lithium source aqueous solution is 25-100°C.
5. The method for preparing the fast ion conductor nano lithium aluminate material according to claim 1, characterized in that: In the step S1, the pH is adjusted by adding 2-8 M acetic acid or citric acid solution to adjust the pH, and heating and stirring the solution to evaporate the water at a temperature of 25-120°C.
6. The method for preparing the fast ion conductor nano lithium aluminate material according to claim 1, characterized in that: In the step S2, the calcination conditions include: a heating rate of 2-10°C / min, a calcination temperature of 700-900°C, and a holding time of 2-10 h.
7. A fast ion conductor nano lithium aluminate material, characterized in that: The fast ion conductor nano lithium aluminate material is prepared by the preparation method described in any one of claims 1-6.
8. The fast ion conductor nano lithium aluminate material according to claim 7, characterized in that: The lithium aluminate is γ-LiAlO2, and the particle size of the nano lithium aluminate material is 60-120 nm.