TW202128554A - Amorphous lithium ion conducting oxide powder and method for production thereof, and method for production of lithium ion conducting oxide powder having nasicon-type crystal structure - Google Patents

Abstract

The present invention provides: Amorphous lithium ion conductive oxide powder with high ion conductivity that can be crystallized into a lithium ion conductive oxide powder with a NASICON (sodium super ion conductor) crystal structure; using cheap raw material costs and The production cost is a method for manufacturing the amorphous lithium ion conductive oxide powder; and the lithium ion conductive oxide powder with a NASICON crystal structure that exerts higher ion conductivity. The amorphous lithium ion conductive oxide powder provided by the present invention contains: lithium: 0.5% by mass or more and 6.5% by mass or less, aluminum: more than 0% by mass and 25.0% by mass or less, germanium: more than 0% by mass and 65.0 Mass% or less, phosphorus: 10 mass% or more and 30 mass% or less, carbon: more than 0 mass% and 0.35 mass% or less; and the specific surface area measured by the BET single-point method is 15m ² /g or more and 100m ² / g or less.

Description

Amorphous lithium ion conductive oxide powder and its manufacturing method, and a method for manufacturing lithium ion conductive oxide powder with NASICON crystal structure

The present invention relates to an amorphous lithium ion conductive oxide powder and a manufacturing method thereof, and a method for manufacturing a lithium ion conductive oxide powder having a NASICON (sodium super ion conductor) crystal structure.

The solid electrolyte material of all solid-state batteries is a lithium ion conductor with a higher ion conductivity of NASICON crystal structure, one of which is the well-known general formula Li _1+x Al _x Ge _2-x (PO ₄ ) ₃ (x of The range is the lithium ion conductor described in 0<x≦1) (in the present invention, it may be described as "LAGP").

Furthermore, the so-called "NASICON type crystal structure" has a space group R3c and is known to have a high lithium ion conductivity. Whether the measurement object is a NASICON crystal structure can be determined by powder X-ray diffraction measurement. For example, the aforementioned LAGP situation can be identified by performing JCPDS card No. 01-080-1922 comparison.

A lithium ion conductor with a NASICON crystal structure is capable of obtaining high ion conductivity. As in Patent Documents 1 and 2, it is known that after molding it using LAGP in an amorphous state, it is calcined to crystallize it.

The following methods are known for the manufacturing method of amorphous LAGP: 1. A method of manufacturing amorphous LAGP by a sol-gel method using metal alkoxides (refer to Patent Document 1). 2. A method of manufacturing amorphous LAGP by the glass melting method (refer to Patent Document 2 paragraph [0018]). [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2018-37341 [Patent Document 2] Japanese Patent Laid-Open No. 2018-101467

(The problem to be solved by the invention)

However, according to the review of the present inventors, even if the amorphous LAGP manufactured in accordance with the methods described in Patent Documents 1 and 2 is used to produce a molded body, and then the molded body is calcined to crystallize the LAGP, ion conduction The degree is still low. Therefore, in order to further increase the output of all-solid-state batteries, it is thought of requiring an amorphous lithium ion conductor, which is crystallized by calcination, and can become a lithium ion with a NASICON crystal structure that can exhibit higher ion conductivity. Conductor.

Furthermore, the calcination step described in Patent Document 1 requires the suppression _{of the generation of GeO 2 which} is a component without ion conductivity resistance in order to improve ion conductivity. Therefore, a calcination step under an inert environment is required, which is a relatively high cost of raw materials and production costs. Huge method. Furthermore, the glass melting method described in Patent Document 2 also requires the first LAGP powder with a particle size of 2.1 μm or more and 2.5 μm and a particle size of 0.18 μm or more and 0.25 μm in order to improve ion conductivity. Two types of LAGP, such as the second LAGP powder, are methods with huge raw material costs and production costs. In addition, the melting of raw materials at high temperatures is required, which causes lithium and germanium, which are easily volatile elements, to volatilize during the melting, and there is a problem of composition deviation.

The present invention has been completed in view of the above situation, and the problem to be solved is to provide: using crystallization energy to obtain a lithium ion conductive oxide powder with a NASICON crystal structure exhibiting high ion conductivity, and a lithium ion conductive oxide powder with a NASICON crystal structure Amorphous lithium ion conductive oxide powder that is an oxide powder precursor; a method for manufacturing the amorphous lithium ion conductive oxide powder at low cost of raw materials and production costs; and a NASICON crystal structure that exhibits higher ion conductivity Manufacturing method of lithium ion conductive oxide powder. (Technical means to solve the problem)

In order to solve the above problems, it was discovered that an amorphous lithium ion conductive oxide powder obtained by a powder containing a predetermined amount of elements such as lithium, aluminum, germanium, and phosphorus, and the carbon content and BET specific surface area of the powder were set in a predetermined range , It is a lithium ion conductive oxide powder that is crystallized into a NASICON crystal structure and exhibits high ion conductivity.

Based on the above findings, the inventors of the present invention thought that in addition to the main constituent elements such as lithium, aluminum, germanium, and phosphorus, which are the constituent elements of the amorphous lithium ion conductive oxide powder, it also contains the replacement of the aforementioned main constituent elements as necessary. The raw materials of aluminum or germanium elements, and elements such as phosphorus and silicon, which are additional elements as required, are composed of inorganic compounds that do not contain carbon; and the aqueous solutions of inorganic compounds containing the above-mentioned constituent elements are mixed, and the co-precipitation method is used The slurry containing the constituent elements of the lithium ion conductor is spray-dried, and then the mixture is calcined at a temperature above 300°C and below 500°C, thereby solving the above-mentioned problems.

That is, the first invention for solving the above-mentioned problems is an amorphous lithium ion conductive oxide powder containing: lithium: 0.5% by mass or more and 6.5% by mass or less, aluminum: more than 0% by mass and 25.0% by mass or less, Germanium: more than 0% by mass and 65.0% by mass or less, phosphorus: 10% by mass or more and 30% by mass or less; and the specific surface area measured by the BET single-point method is 15 m ² /g or more and 100 m ² /g or less. The second invention is the amorphous lithium ion conductive oxide powder described in the first invention, which contains: lithium: 1 mass% or more and 4 mass% or less, aluminum: more than 0 mass% and 6 mass% or less, germanium : More than 15% by mass and 35% by mass or less. The third invention is the amorphous lithium ion conductive oxide powder as described in the first or second invention, which further contains carbon: 0.01% by mass or more and 0.35% by mass or less. The fourth invention is the amorphous lithium ion conductive oxide powder as described in any one of the first to third inventions, wherein the specific surface area measured by the BET single-point method is 20 m ² /g or more and 100 m ² /g or less. The fifth invention is the amorphous lithium ion conductive oxide powder as described in any one of the first to fourth inventions, which further contains at least one element selected from titanium, zirconium, and hafnium. The sixth invention is the amorphous lithium ion conductive oxide powder as described in any one of the first to fifth inventions, which further contains silicon: 10% by mass or less. The seventh invention is the amorphous lithium ion conductive oxide powder according to any one of the first to sixth inventions, wherein the amorphous lithium ion conductive oxide powder is based on the general formula Li _1+x+w (Al _1-y M1 _y ) _x (Ge _1-z M2 _z ) _2-x P _3-w Si _w O _{As shown in the formula 12} , M1 is one or more selected from gallium, lanthanum, indium and yttrium, M2 It is one or more selected from titanium, zirconium and hafnium, the range of x is 0＜x≦1.0, the range of y is 0≦y≦1.0, the range of z is 0≦z≦1.0, and the range of w is 0≦ w≦1.0. The eighth invention is the amorphous lithium ion conductive oxide powder as described in any one of the first to sixth inventions, which further contains at least one element selected from gallium, lanthanum, indium, and yttrium. The ninth invention is a method for producing amorphous lithium ion conductive oxide powder, which includes: mixing a lithium compound aqueous solution, an aluminum compound aqueous solution, a germanium compound aqueous solution, and an ammonium phosphate salt aqueous solution to obtain a coprecipitate suspension The step of forming the slurry; the step of spray drying the slurry to obtain a dried slurry; and the step of calcining the dried slurry at a temperature above 300°C and below 500°C. The tenth invention is the method for producing amorphous lithium ion conductive oxide powder according to the ninth invention, wherein in the slurry forming step, at least one selected from gallium, lanthanum, indium, and yttrium is further mixed and contained The aqueous solution of the compound of the element, and the coprecipitate suspension is obtained. The eleventh invention is the method for producing amorphous lithium ion conductive oxide powder according to the ninth or tenth invention, wherein in the slurry forming step, at least one selected from titanium, zirconium, and hafnium is further mixed and contained A compound aqueous solution of an element to obtain a co-precipitate suspension. The twelfth invention is the method for producing amorphous lithium ion conductive oxide powder according to any one of the ninth to eleventh inventions, wherein in the slurry forming step, an aqueous silicon compound solution is further mixed to obtain a total Sediment suspension. The thirteenth invention is the method for producing an amorphous lithium ion conductive oxide powder as described in any one of the ninth to twelfth inventions, wherein the slurry forming step in the slurry forming step is formed by mixing It is adjusted to the above-mentioned germanium compound aqueous solution having a pH of 8 or higher. The fourteenth invention is a method for producing lithium ion conductive oxide powder with a NASICON crystal structure. The calcination step is performed at a temperature higher than 500°C. The fifteenth invention is a method for producing lithium ion conductive oxide powder with a NASICON crystal structure, which includes: mixing a lithium compound aqueous solution, an aluminum compound aqueous solution, a germanium compound aqueous solution, and an ammonium phosphate salt aqueous solution to obtain co-precipitation The step of forming a slurry of the slurry suspension; the step of spray drying the slurry to obtain a dried slurry; and the step of calcining the dried slurry at a temperature higher than 500°C. (Compared to the effect of the previous technology)

According to the present invention, it is possible to provide: Amorphous lithium ion that is a lithium ion conductive oxide powder with a NASICON crystal structure that exhibits high ion conductivity and is a precursor of lithium ion conductive oxide powder with a NASICON crystal structure can be provided by crystallization. Conductive oxide powder; a method for manufacturing the amorphous lithium ion conductive oxide powder at low cost of raw materials and production costs; and a method for manufacturing lithium ion conductive oxide powder with a NASICON crystal structure that exerts higher ion conductivity.

The amorphous lithium ion conductive oxide powder of the present invention is crystallized by calcination to obtain a precursor of the lithium ion conductive oxide powder with a NASICON crystal structure. The amorphous lithium ion conductive oxide powder and the lithium ion conductive oxide powder of the NASICON crystal structure of the present invention are, for example, the general formula Li _1+x+w (Al _1-y M1 _y ) _x (Ge _1-z M2 _z ) _2-x P _3-w Si _w O ₁₂ (where M1 is one or more selected from gallium, lanthanum, indium and yttrium, M2 is one or more selected from titanium, zirconium and hafnium, and x is The range is 0<x≦1.0, the range of y is 0≦y≦1.0, the range of z is 0≦z≦1.0, and the range of w is 0≦w≦1.0). After the amorphous lithium ion conductive oxide powder of the present invention is formed into a pellet shape or into a sheet shape, for example, by calcining the formed product to crystallize, a lithium ion conductive oxide powder having a NASICON crystal structure can be manufactured. Calcined body of oxide powder. The calcined body of lithium ion conductive oxide powder with NASICON crystal structure is used in all solid-state batteries in the form of solid electrolyte. Hereinafter, regarding the lithium ion conductive oxide powder of the present invention, its manufacturing method, and the manufacturing method of lithium ion conductive oxide powder having a NASICON crystal structure, in accordance with [1] constituent elements, [2] BET specific surface area, [3 ] The order of the manufacturing method will be described.

[1] Constituent Elements The amorphous lithium ion conductive oxide powder of the present invention contains at least lithium, aluminum, germanium, and phosphorus as the constituent elements. Lithium is ^{an element that provides Li +} carriers and enables lithium ions to conduct. The aluminum-based replacement of germanium, which is a tetravalent metal element described later, is used as a charge compensation for the trivalent element added for the purpose of ^{increasing Li + carriers.} The germanium-based tetravalent metal element is necessary for the lithium ion conductive oxide powder to become the NASICON crystal structure during crystallization; the phosphorus system is necessary for the lithium ion conductive oxide powder to become the NASICON crystal structure during crystallization 5 Valence metal elements.

In addition, aluminum and germanium, which are the above-mentioned constituent elements, may be partially substituted with other elements. A part of aluminum can be substituted with one or more elements selected from gallium, lanthanum, indium, and yttrium. Part of the germanium system can be replaced with one or more elements selected from titanium, zirconium, and hafnium.

Part of the phosphorus system can be replaced with silicon. By replacing 5-valent phosphorus with 4-valent silicon, Li ⁺ carriers can be increased, which contributes to the improvement of Li ion conductivity.

Here, the content ratio of the main constituent substances will be described. Lithium contains 0.5% by mass or more and 6.5% by mass or less in the form of lithium element. The reason is that if the lithium content is 0.5% by mass or more, the lithium ion conductivity can be ensured. On the other hand, if the lithium content is 6.5% by mass or less, the lithium ion conductive oxide powder will have a NASICON structure during crystallization. The lithium content is preferably 1.0% by mass or more, more preferably 1.5% by mass or more, particularly preferably 1.8% by mass or more, more preferably 4.0% by mass or less, more preferably 3.5% by mass or less, and particularly preferably 3.3% by mass the following.

The aluminum system contains more than 0 mass% and 25.0 mass% or less in the form of aluminum element. The reason is that by adding aluminum, the lithium ion conductivity in the lithium ion conductive oxide powder with a NASICON crystal structure can be improved. If the aluminum content is 25.0% by mass or less, the lithium ion conductive oxide powder will have a NASICON crystal structure during crystallization. The aluminum content is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, more preferably 6.0% by mass or less, more preferably 5.5% by mass or less, particularly preferably 5.0% by mass or less.

Germanium contains more than 0% by mass and less than 65.0% by mass depending on the form of germanium. If the germanium content exceeds 0% by mass, glass is formed, which can become amorphous. On the other hand, if the germanium content is 65.0% by mass or less, the lithium ion conductive oxide powder will have a NASICON crystal structure during crystallization. The germanium content is preferably 15% by mass or more, more preferably 20% by mass or more, particularly preferably 22% by mass or more, more preferably 35% by mass or less, more preferably 33% by mass or less, and particularly preferably 30% by mass the following.

In the amorphous lithium ion conductive oxide powder of the present invention, the phosphorus-based phosgene element contains 10% by mass or more and 30% by mass or less. In this case, glass is formed and can become amorphous. On the other hand, during crystallization, the lithium ion conductive oxide powder has a NASICON crystal structure. The phosphorus content is preferably 15% by mass or more, more preferably 20% by mass or more, more preferably 28% by mass or less, and more preferably 25% by mass or less.

The content of each element (mass%) of the amorphous lithium ion conductive oxide powder of the present invention described above is that the amorphous lithium ion conductive oxide powder is made into an alkali-melted solution, and then a luminescence analyzer (Agilent ICP-720 (manufactured by the company), the quantitative analysis of each of the constituent elements of the solution to obtain the value of the result of the quantitative analysis of each of the constituent elements.

In the amorphous lithium ion conductive oxide powder of the present invention, the carbon content is preferably 0.35% by mass or less. When the carbon content is 0.35 mass% or less, it is possible to suppress the combustion of the carbon and the generation of pores in this portion when calcination is performed for crystallization, which may result in deterioration of ion conductivity. The carbon content system of the amorphous lithium ion conductive oxide powder can be set to, for example, 0.01% by mass or more and 0.35% by mass or less. The carbon content is preferably 0.3% by mass or less, more preferably 0.25% by mass or less. Furthermore, the method for measuring the carbon content will be described in the examples.

Furthermore, in the amorphous lithium ion conductive oxide powder of the present invention, the total of lithium element, aluminum element, germanium element, and optionally the above-mentioned substitution metal element, phosphorus element, carbon, and oxygen contained 90.0% by mass or more and 100.0% by mass or less, more preferably 95.0% by mass or more. The rest are impurities.

On the other hand, the amount of oxygen in the amorphous lithium ion conductive oxide powder of the present invention is calculated from the foregoing metal elements and phosphorus as oxides, and the amounts of each metal element and phosphorus measured by ICP analysis. The amount of oxygen in the amorphous lithium ion conductive oxide powder is preferably 25-60% by mass. On the other hand, the amount of impurities is obtained by subtracting the respective amounts of metal elements, phosphorus, carbon, and oxygen from 100% by mass. A specific example of calculation will be described in the embodiment.

Furthermore, the amorphous lithium ion conductive oxide powder of the present invention may further contain 10% by mass or less of silicon. By adding silicon, it is easier to form glass. If the amount of silicon added exceeds 10% by mass, the lithium ion conductive oxide powder cannot become a NASICON crystal structure during crystallization, resulting in deterioration of ion conductivity. The silicon content is preferably 5% by mass or less, more preferably 3% by mass or less.

When the amorphous lithium ion conductive oxide powder of the present invention contains silicon, the total content of lithium, aluminum, germanium, phosphorus, carbon, oxygen, and silicon atoms will be 90.0% by mass or more. 100.0% by mass or less, more preferably 95.0% by mass or more.

On the other hand, the amorphous lithium ion conductive oxide powder of the present invention contains lithium element, aluminum element, germanium element, the above-mentioned substitution metal element, phosphorus element, carbon, and oxygen as needed, and also contains When the impurity is about 10% by mass, preferably about 3.0% by mass. This impurity can be considered to be the zirconium dioxide of the spherical beads used in the production of the amorphous lithium ion conductive oxide powder. Lithium ion conductive properties cause special adverse effects.

[2] BET specific surface area The BET specific surface area of the amorphous lithium ion conductive oxide powder of the present invention is 15 m ² /g or more and 100 m ² /g or less. The reason is that if ^{the BET specific surface area is 15m 2} /g or more and 100m ² /g or less, when the lithium ion conductive oxide powder is calcined, the contained lithium ion conductor particles can be uniformly heated. The entire particles are uniformly crystallized, and the ion conductivity can be improved. The BET specific surface area is preferably 20 m ² /g or more, more preferably 22 m ² /g or more, more preferably 80 m ² /g or less, more preferably 60 m ² /g or less. In addition, the specific measurement method of the BET specific surface area will be described in the examples.

[3] Manufacturing method The method for producing the amorphous lithium ion conductive oxide powder and the lithium ion conductive oxide powder having a NASICON crystal structure of the present invention will be described. When manufacturing the amorphous lithium ion conductive oxide powder of the present invention and the lithium ion conductive oxide powder having a NASICON crystal structure, first, the raw materials containing the constituent elements are completely dissolved in water to form an aqueous solution, and each constituent The element is in an ionic state. The aqueous solutions of the respective constituent elements are mixed, and the respective constituent elements are precipitated to obtain a slurry. After spray-drying the obtained slurry to form a powder, the calcined product obtained by calcination is pulverized to obtain a powder. When precipitation is generated from an aqueous solution in which each constituent element is dissolved, acidic solutions and alkaline solutions may be mixed in advance.

Hereinafter, referring to the method for manufacturing the amorphous lithium ion conductive oxide powder and the lithium ion conductive oxide powder having a NASICON crystal structure of the present invention, refer to the flowchart showing the manufacturing steps of the amorphous lithium ion conductive oxide powder Figure 1 illustrates in the following order: (1) preparation of raw material aqueous solution, (2) mixing, (3) spray treatment, (4) calcination, (5) pulverization, (6) drying, (7) calcination, (8) ) Manufacturing of lithium ion conductive oxide powder with NASICON crystal structure.

(1) Preparation of raw material aqueous solution The raw materials containing the constituent elements of lithium ion conductive oxide powder of the present invention, including lithium, aluminum, germanium, phosphorus, and optional replacement elements of aluminum and germanium, and phosphorus and silicon, which are added elements, are completely dissolved. Form an aqueous solution in water. At this time, if the raw material is a water-soluble salt that does not contain carbon or an element that dissolves according to liquid properties, an acid or a base may be added to the oxide of each element to dissolve it.

On the other hand, when a carbon-containing raw material, such as acetate or organic acid salt of each element, is used, the carbon may remain in the lithium ion conductive oxide powder of the present invention. From this viewpoint, the raw material containing each constituent element is preferably an inorganic compound.

According to the above, examples of the raw material compound of each element suitable for the preparation of the raw material aqueous solution are shown in Table 1. At this time, in Table 1, if the pH of the dissolved aqueous solution is acidic, the acidic raw material aqueous solutions may be mixed with each other. In addition, it is also possible to further add and dissolve other raw material powders in the acidic raw material aqueous solution. The same applies to the alkaline raw material aqueous solutions.

For example, in the case of germanium dioxide as the raw material compound, an aqueous germanium solution can be prepared by adding germanium dioxide to pure water and stirring, and further adding an alkali. At this time, there is no need to review the temperature during dissolution, and it may be heated or not. The reason is that germanium dioxide will dissolve in the pH range of 8-12.

When a water-insoluble material is used as the raw material compound, the liquidity of the solution is adjusted, but it is preferable to use ammonia that does not retain impurities as the base. The acid system can be used: nitric acid, sulfuric acid, hydrochloric acid, etc. In addition, an aqueous lithium hydroxide solution can also be used as the base. In this case, of course, the lithium hydroxide can also be weighed and used as a raw material compound of lithium.

[Table 1] Contains elements Compound Examples raw material Liquidity after dissolution Li Lithium Nitrate Acidic Lithium Sulfate Acidic Lithium Chloride Alkaline Lithium Hydroxide Alkaline Al Aluminum nitrate nonahydrate Acidic Aluminum sulfate Acidic Aluminum Chloride Acidic Ge Aqueous solution of germanium dioxide dissolved in ammonia Alkaline Use LiOH aqueous solution to dissolve germanium dioxide aqueous solution Alkaline p Phosphoric acid Acidic Ammonium Dihydrogen Phosphate Acidic Diammonium Phosphate Alkaline M1 Ga Gallium Nitrate Acidic La Lanthanum Nitrate Acidic In Indium(III) nitrate trihydrate Acidic Y Yttrium Nitrate Acidic M2 Ti Aqueous solution of titanium ammonium peroxide complex Alkaline Titanium Sulfate Acidic Zr Zirconium nitrate Acidic Zirconium Sulfate Acidic Zirconium chloride Acidic Hr Hafnium Chloride Acidic Si Use LiOH aqueous solution to dissolve SiO ₂ aqueous solution Alkaline

(2) Mixing (slurrying) The step of mixing the raw material aqueous solution prepared according to the above (1) with the composition of the target lithium ion conductive oxide powder, and using the co-precipitation method to obtain a slurry containing the constituent elements of the lithium ion conductor. For example, adding an acidic aqueous solution of lithium nitrate, aluminum nitrate nonahydrate, and ammonium dihydrogen phosphate to an alkaline germanium aqueous solution dissolved in ammonia, and then immediately using the turbidity and co-precipitation method to obtain lithium, aluminum, Pastes of germanium, phosphorus, etc. The liquid temperature in this mixing step does not require special review, and it can be heated or not. It is considered that there are constituent elements precipitated in the form of hydroxides and constituent elements existing in the form of ions in the slurry. In addition, in order to reduce the amount of carbon derived from carbonic acid in the slurry, it is preferable to perform nitrogen flushing on the slurry.

In the present invention, the raw material aqueous solution is mixed, and then the co-precipitation method is used to obtain a slurry containing the constituent elements of the lithium ion conductor, in order to achieve a higher ion concentration product of the constituent elements in the mixed solution by adopting the co-precipitation method. The supersaturated state of the solubility product. The reason is that by achieving this supersaturated state, the number of nuclei of the formed precipitate will increase, and as a result, the particle size of the precipitated precipitate will be reduced, and the effect of increasing the BET specific surface area of the amorphous lithium ion conductor particles can finally be obtained. . In addition, the co-precipitation method of the present invention may not be able to precipitate all the constituent elements of the lithium ion conductor, but most of the constituent elements will co-precipitate, and the uniformity of the constituent elements of the amorphous lithium ion conductor particles can also be improved. Effect.

In contrast, when dehydration is performed from an aqueous raw material solution in which constituent elements are completely dissolved, precipitation occurs due to changes in solubility, and it does not undergo rapid supersaturation due to changes in pH as in the co-precipitation method described above. As a result, the number of nuclei of the formed precipitate is reduced, resulting in an increase in the particle size of the precipitated precipitate. In addition, because there are different solubility according to the constituent elements, during the dehydration process, constituent elements with low solubility will be precipitated first, and constituent elements with high solubility will be precipitated later, so there will also be some unevenness in the generated particles. possibility.

(3) Spray drying The step of spray-drying the slurry obtained in (2) above using a spray dryer or the like to evaporate the water in the slurry to obtain a powder. Here, the reason for designing the drying step is that, in the slurry obtained in (2) above, lithium, aluminum, germanium, phosphorus, which are constituent elements, and the above-mentioned replacement metal elements added as necessary, although most of them share the same Shen, but there are also those who rely on ions. For example, if the powder recovered from the slurry in the filtration step is used, it is considered that a lithium ion conductor having a theoretical composition cannot be obtained.

On the other hand, from the obtained slurry, instead of spray drying, it can be dried by evaporation using a hot plate or the like to obtain a powder. However, if the dehydration time is too long, the solubility of the constituent elements existing in the slurry is poor, which may cause the constituent elements to precipitate unevenly. Here, by performing dehydration as early as possible, the unevenness of precipitation caused by the difference in solubility between constituent elements can be reduced. Therefore, it can be considered that the spray drying method has a more uniform particle composition effect than the method such as evaporation drying. In addition, from the viewpoint of the production side, a spray drying method that can remove the solvent in a short time is preferable.

By performing spray drying, the elements contained in the slurry will remain in the dry powder, but by calcining the obtained dry powder, the remaining impurities can be evaporated and removed by heat. In addition, in order to remove impurities, a step of washing the dried powder to remove impurities and then drying it may be added.

(4) calcination The step of calcining the powder obtained in (3) above to remove residual ammonia and nitric acid components from the raw material in the powder to obtain amorphous lithium ion conductive oxide powder; or without removing the amorphous lithium ion conductive oxide powder In the case of ion conductive oxide powder, a step of obtaining lithium ion conductive oxide powder with a NASICON crystal structure. Hereinafter, the steps of (I) obtaining an amorphous lithium ion conductive oxide powder; and (II) obtaining a lithium ion conductive oxide powder having a NASICON crystal structure will be described.

(I) Obtaining amorphous lithium ion conductive oxide powder As mentioned above, by pressing and calcining the amorphous lithium ion conductor powder, a dense compact can be obtained. However, there will be impurities such as ammonia and nitric acid in the amorphous lithium ion conductive oxide powder. When calcination is carried out in a state where the impurities are contained, the impurities will burn or volatilize, resulting in pores in this part, and there may be cases in which dense particles cannot be obtained. Therefore, the calcination of the amorphous lithium ion conductive oxide powder is performed at a temperature below 500°C.

Specifically, the amorphous lithium ion conductor powder obtained in (3) above is placed in a container made of alumina or the like, and the temperature is increased from room temperature to 300°C to 500°C at a temperature increase rate of 0.1 to 20°C/min. By calcination at a temperature above 300°C, ammonia and nitric acid components can be easily removed. On the other hand, if it is set at 500°C or less, crystallization of the lithium ion conductor can be avoided. Furthermore, by performing calcination for 60 to 180 minutes after reaching 300°C to 500°C, amorphous lithium ion conductive oxide powder can be obtained. The calcination environment is not limited to the atmospheric environment, and may be a nitrogen environment. However, from the viewpoint of cost and productivity, an atmospheric environment is preferable; from the viewpoint of suppressing the formation of lithium carbonate, a nitrogen environment is preferable.

(II) Obtaining lithium ion conductive oxide powder with NASICON crystal structure Specifically, as described above, the amorphous lithium ion conductive oxide powder obtained in (3) above is placed in a container made of alumina, etc., in order to obtain a lithium ion conductive oxide powder with a NASICON crystal structure. Calcining is performed at a temperature exceeding 500°C, preferably 550°C or higher and 900°C or lower, to crystallize, and a lithium ion conductive oxide powder having a NASICON crystal structure can be obtained. The heating rate is not particularly limited, and it is preferably 1-20°C/min. The calcination environment is not particularly limited, and it is preferably an atmospheric environment. The calcination time is not particularly limited, but it is preferably performed for 30 minutes or more and 300 minutes or less after reaching more than 500°C and 900°C or less.

(5) Grinding The amorphous lithium ion conductive oxide powder obtained according to (4) above is pulverized to the particle size required in the subsequent steps. The particle size of the amorphous lithium ion conductive oxide powder does not affect ion conductivity. However, for example, in the case of molding lithium ion conductive oxide powder into a sheet shape, it is preferable not to have particles having a target sheet thickness or more, but to adjust the particle size. A known method can be used for the pulverization method, and wet pulverization using a bead mill or the like is preferable. In the case of wet pulverization, solid-liquid separation is performed after the treatment, and then the lithium ion conductive oxide powder is dried. For example, the preferred particle size of the amorphous lithium ion conductive oxide powder is a volume-based cumulative 50% particle size (D ₅₀ ) of 1 μm to 5 μm.

The solvent in the wet pulverization is preferably an organic solvent, and specifically, IPA is preferable. The reason is that IPA volatilizes during drying after pulverization, and therefore does not remain in the lithium ion conductive oxide powder. When the solvent is water, lithium will exchange with protons, which may cause deterioration of lithium ion conductivity. Furthermore, when a bead mill is used for the crushing, the balls are preferably zirconia balls. Through the above steps (1) to (5), the amorphous lithium ion conductive oxide powder of the present invention can be obtained.

(6) Dry In the step (5) above, the amorphous lithium ion conductive oxide powder is subjected to wet pulverization, followed by solid-liquid separation such as filtration, depending on the temperature above the boiling point of the solvent used, and the above (4) Drying is performed in a temperature range below the calcination temperature of the step, and the solvent used is removed to obtain the lithium ion conductive oxide powder of the present invention. Particularly, in the case where the lithium ion conductive oxide powder is dry-pulverized in the step (5) above, even if this drying step is omitted, the lithium ion conductive oxide powder of the present invention can be obtained.

Whether the lithium ion conductive oxide powder is amorphous is measured by powder X-ray diffraction (XRD), and it can be confirmed by observing the halo in the region of 2θ: 15°~40°. In addition, the so-called "halo" means that the X-ray intensity gradually fluctuates and broad ridges appear in the X-ray image. In addition, the half-value width of the halo is 2θ: 2° or more.

(7) Calcination The amorphous lithium ion conductive oxide powder obtained in (6) above is calcined and crystallized, and a lithium ion conductive oxide powder having a NASICON crystal structure can be produced. The calcination temperature is more than 500°C, preferably 550°C or more and 900°C or less. The calcination environment is not particularly limited, and it is preferably an atmospheric environment. The calcination time is not particularly limited, but it is preferably performed for 30 minutes or more and 300 minutes or less after reaching more than 500°C and 900°C or less.

(8) Lithium ion conductive oxide powder with NASICON crystal structure In the above, the lithium ion conductive oxide powder with the NASICON crystal structure can be manufactured through the steps described above. The lithium ion conductive oxide powder having a NASICON crystal structure contains the same elements as those contained in the amorphous lithium ion conductive oxide powder before crystallization. Whether the present invention is a lithium ion conductor with a NASICON crystal structure is measured by using an XRD device to obtain an XRD distribution. Use the computer attached to the XRD device to compare the obtained XRD distribution with JCPDS card No.01-080-1922 to identify the crystal structure. [Example]

(Example 1) According to the above-mentioned manufacturing step flow of the amorphous lithium ion conductive oxide powder, the amorphous lithium ion conductive oxide powder of Example 1 was manufactured. Then, analysis and characteristic evaluation of the amorphous lithium ion conductive oxide powder of Example 1 were performed.

(1) Preparation of raw material aqueous solution In Example 1, the raw material aqueous solution was prepared (I) an aqueous germanium solution: alkaline, and (II) an aqueous solution containing lithium, aluminum, and phosphorus: acidic. Hereinafter, they will be explained separately.

(I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 21.7 g of lithium nitrate, 39.4 g of aluminum nitrate nonahydrate, and 72.5 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 1.4, which is acidic.

(2) Mixing (slurrying) Divide 720 g of the above alkaline germanium aqueous solution and heat it to 40°C while stirring. Add the total amount (283.7 g) of the above acidic aqueous solution containing lithium, aluminum and phosphorus (283.7 g). White turbidity, white slurry was obtained. The pH value of the obtained white slurry was 4.3.

(3) Spray drying The white slurry was spray-dried using a spray dryer (SD-1000 manufactured by Tokyo Rika Instruments Co., Ltd.) to evaporate water in the white slurry and precipitate a solid phase at one go to obtain a white powder. In addition, the conditions of spray drying were as follows: an inlet temperature of 180°C, an outlet temperature of 90°C, and the addition rate of the white slurry was 10 g/min.

(4) calcination A container made of alumina was filled with the white powder obtained by the above spray drying, and the temperature was raised from room temperature to 400°C at a heating rate of 5°C/min. After reaching 400°C, it was convenient to perform 120 minutes of calcination in an atmospheric environment to obtain a Crystalline lithium ion conductive oxide powder. The 30,000 times SEM photograph of the obtained amorphous lithium ion conductive oxide powder is shown in FIG. 2 (Example 1).

1mmZr球珠160g及IPA：94.32g裝填於珠磨機中，施行120分鐘濕式粉碎而調整粒度，獲得經調整粒度的非晶質鋰離子傳導氧化物粉末。(5) Wet-grinding 40g of the above-mentioned amorphous lithium ion conductive oxide powder together with

160g of 1mmZr balls and 94.32g of IPA: 94.32g were packed in a bead mill, and wet pulverization was performed for 120 minutes to adjust the particle size to obtain an amorphous lithium ion conductive oxide powder with an adjusted particle size.

(6) Drying The amorphous lithium ion conductive oxide powder with the adjusted particle size is put into a dryer, and dried at 100°C for 3 hours to remove IPA to obtain the amorphous lithium ion conductive oxide of Example 1. powder. The volume-based cumulative 50% particle size (D ₅₀ ) of the amorphous lithium ion conductive oxide powder of Example 1 was measured by Helos (dispersion pressure 5 bar), and the result was 1.8 μm. This value is recorded in Table 3.

(7) Amorphous lithium ion conductive oxide powder For the obtained amorphous lithium ion conductive oxide powder, implement: (I) composition analysis, (II) carbon content analysis, (III) oxygen content calculation, (IV) BET specific surface area measurement, (V) amorphous lithium XRD measurement of ion conductive oxide powder, (VI) evaluation of ion conductivity, (VII) XRD measurement of pressed powder calcined body of lithium ion conductor. Hereinafter, each method and result will be described.

(I) Composition analysis The amorphous lithium ion conductive oxide powder of Example 1 was subjected to alkali dissolution using sodium carbonate as a flux. Then, the solution was subjected to elemental analysis using an ICP device (ICP-720 manufactured by Agilent) to obtain lithium: 2.43 mass%, aluminum: 3.02 mass%, germanium: 25.1 mass%, and phosphorus: 21.7 mass%. The analysis values of each constituent element are shown in Table 2.

(II) Carbon analysis The amount of carbon in the amorphous lithium ion conductive oxide powder of Example 1 was measured using a trace carbon and sulfur analyzer (EMIA-U510 manufactured by Horiba Manufacturing Co., Ltd.), and the result was 0.16 mass%. This value is recorded in Table 2.

(III) Calculating the amount of oxygen The amount of oxygen in the amorphous lithium ion conductive oxide powder is calculated as follows. 1 belongs to a monovalent lithium oxide Li ₂ O, and thus the amount of oxygen-based lithium oxide according to the formula numerals: oxygen = lithium oxide (Li concentration × (Li ₂ O in an amount of formula / Li ₂ O of Li atoms (Number) ÷ formula weight of Li)-Li concentration...(Formula) On the other hand, the result of ICP analysis using the above (I) for lithium concentration is 2.43% by mass, so the following formula is established: Oxygen content of lithium oxide =(2.43×(29.88/2)÷6.94)-2.43=2.80 mass%

The oxide of trivalent aluminum is Al ₂ O ₃ , so the oxygen content of aluminum oxide is marked by the following formula: Oxygen content of aluminum oxide=(Al concentration×(Al ₂ O ₃ formula weight/Al ₂ O ₃ The number of Al atoms) ÷ the formula weight of Al)-Al concentration... (Equation) On the other hand, the ICP analysis result of aluminum concentration is 3.02% by mass, so the following formula is established: Oxygen content of aluminum oxide = (3.02× (101.96/2)÷26.98)-3.02=2.69 mass%

Oxide GeO _2, and thus the amount of oxygen-based germanium oxide of a tetravalent germanium marker by the formula: oxygen germanium oxide = (Ge concentration × (GeO ₂ is the formula weight / GeO Ge atom number) ÷ ₂ Ge formula weight)-Ge concentration... (Equation) On the other hand, the ICP analysis result of germanium concentration is 25.1% by mass, so the following formula is established: Oxygen content of germanium oxide = (25.1 × (104.61/1) ÷ 72.61)-25.1=11.06 mass%

The oxide of pentavalent phosphorus is P ₂ O ₅ , so the oxygen content of phosphorus oxide is marked by the following formula: Oxygen content of phosphorus oxide=(P concentration×(P ₂ O ₅ formula weight/P ₂ O ₅ The number of P atoms) ÷ the formula weight of P)-P concentration...(Formula) On the other hand, the ICP analysis result of phosphorus concentration is 21.7 mass%, so the following formula is established: Oxygen content of phosphorus oxide = (21.7× (141.94/2)÷30.97)-21.7=28.02% by mass

From the above calculation results, if the total oxygen content of each metal element oxide and phosphorus oxide is 2.80+2.69+11.06+28.02=44.6 mass%. This value is recorded in Table 2. The obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ . Furthermore, from the respective amounts of the above-mentioned metal elements, phosphorus, carbon, and oxygen, the amount of impurities is calculated to be 3.0% by mass. This value is recorded in Table 2.

(IV) BET specific surface area measurement The BET specific surface area of the amorphous lithium ion conductive oxide powder of Example 1 was measured using a BET specific surface area measuring device (Macsorb manufactured by MOUNTECH Co., Ltd.). In this measuring instrument, after degassing by circulating nitrogen gas at 105°C for 20 minutes, a mixed gas of nitrogen and helium (N ₂ : 30 vol%, He: 70 vol%) was circulated, and the measurement was carried out by the BET single-point method. The BET specific surface area of the amorphous lithium ion conductive oxide powder of Example 1 was 27.7 m ² /g. This value is recorded in Table 3.

(V) XRD measurement of amorphous lithium ion conductive oxide powder The amorphous lithium ion conductive oxide powder of Example 1 was subjected to XRD measurement. The measurement conditions are shown in Table 4, and the obtained XRD spectrum is shown in FIG. 3. It can be confirmed from FIG. 3 that the lithium ion conduction system of Example 1 has an amorphous structure. This matter is recorded in Table 3. This item is determined by XRD measurement, and halo is observed in the area of 2θ: 15°~40°. In addition, the so-called "halo" means that the X-ray intensity gradually fluctuates and broad ridges appear in the X-ray image. Furthermore, the half-value width of the halo is 2θ: 2° or more.

(VI) Evaluation of ion conductivity: 0.5 g of the amorphous lithium ion conductive oxide powder of Example 1 was placed in a cylindrical insulating container with a diameter of 10 mm, and the result was obtained by pressing at 360 MPa using a stainless steel current collector and a punching machine. Press powder. The obtained powder compact of amorphous lithium ion conductive oxide powder is calcined for 120 minutes after the temperature in the furnace reaches 700°C to obtain crystallized lithium ion conductive oxide powder with a NASICON crystal structure. (Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ ) pressed powder calcined body.

For the compressed powder calcined body of lithium ion conductive oxide powder with NASICON type crystal structure manufactured by the above calcination, use a potentiostat/galvanostat (1470E manufactured by Solartron) and frequency direction in an atmospheric environment at a temperature of 25°C. The analyzer (1255B manufactured by Solartron) was used for measurement in the range of 100 Hz to 4 MHz by the AC impedance method. Then, the resistance value of the powder calcined body with NASICON crystal structure is obtained from the Cole-Cole trace (complex impedance plane trace) of the measured value, and the amorphous lithium ion conductive oxide is calculated from the obtained resistance value The ion conductivity of the lithium ion conductive oxide powder with a NASICON crystal structure after the powder was crystallized was 6.4×10 ^-5 S/cm. This value is recorded in Table 3.

(VII) XRD measurement of pressed powder calcined body of lithium ion conductor The compressed powder calcined body of the lithium ion conductor crystallized by firing at 700°C for 120 minutes was subjected to XRD measurement under the conditions described in the above "(V) XRD measurement of amorphous lithium ion conductive oxide powder", and JCPDS card No. 01-080-1922 was compared, and the results showed that LAGP crystal peaks belonging to the lithium ion conductor of the NASICON type crystal structure were observed, and the pressed powder calcined body of the lithium ion conductive oxide powder of Example 1 was found. It is a lithium ion conductor with a NASICON crystal structure. The obtained XRD spectrum is shown in Figure 4.

(Examples 2~8) Except that the steps of "(1) Preparation of raw material aqueous solution" and "(2) Mixing (slurrying)" described in Example 1 were changed in the manner described later, the same operations as in Example 1 were carried out to produce The amorphous lithium ion conductive oxide powders of Examples 2-8. Then, using the amorphous lithium ion conductive oxide powders of the manufactured examples 2 to 8, the "(I) composition analysis, (II) Carbon content analysis, (III) Oxygen content analysis, (IV) BET specific surface area measurement, (V) XRD measurement of amorphous lithium ion conductive oxide powder, (VI) Ion conductivity evaluation, (VII) Lithium XRD measurement of compressed powder calcined body of ion conductor".

In the amorphous lithium ion conductive oxide powders of Examples 2 to 8, the composition analysis results, oxygen content, carbon content, and impurity content of each constituent element are recorded in Table 2, and the volume standard was measured by Helos (dispersion pressure 5 bar) The value of the cumulative 50% particle size (D ₅₀ ), the crystal phase and the BET specific surface area are shown in Table 3. In addition, the ion conductivity of the lithium ion conductive oxide powders with the NASICON crystal structure of Examples 2 to 8 are shown in Table 3. Furthermore, the method for calculating the oxygen content of Ti, Zr, and Si contained in the amorphous lithium ion conductive oxide powders of Examples 5 to 7 is described in each example. In addition, in Examples 5 to 7, the method for calculating the amount of oxygen of elements other than Ti, Zr, and Si is the same as in Example 1.

<Example 2> (1) Preparation of raw material aqueous solution (I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 18.8 g of lithium nitrate, 23.6 g of aluminum nitrate nonahydrate, and 72.5 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 1.5, which is acidic.

(2) Mixing (slurrying) Separate 816 g of the above-mentioned alkaline germanium aqueous solution and heat it to 40°C while stirring. Add the above-mentioned acidic lithium, aluminum, phosphorus, and titanium-containing aqueous solution in full to it. The aqueous solution becomes white turbid immediately after the addition. A white slurry is obtained. The pH value of the obtained white slurry was 6.7.

(3) Amorphous lithium ion conductive oxide powder Using the obtained white slurry, the same operation as in Example 1 was performed to obtain the amorphous lithium ion conductive oxide powder of Example 2. The composition formula of the obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ . Using the amorphous lithium ion conductor powder of Example 2, the XRD measurement was carried out in the same manner as in Example 1. As a result, halo was observed in the region of 2θ: 15°~40°. The half-value width of the halo 2θ: 2° or more.

Using the amorphous lithium ion conductor powder of Example 2, in accordance with the same operation as that of Example 1, the lithium ion conductive oxide powder of Example 2 was obtained, and a pressed powder calcined body of the lithium ion conductor was obtained. Using the compressed powder calcined body of the lithium ion conductor of Example 2, the XRD measurement was carried out according to the same operation as that of Example 1. As a result, it was found that the lithium ion conductive oxide powder of Example 2 is a lithium ion conductive powder with a NASICON crystal structure. Oxide powder (composition formula: Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ ).

<Example 3> (1) Preparation of raw material aqueous solution (I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 22.7 g of lithium nitrate, 23.6 g of aluminum nitrate nonahydrate, and 72.5 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 1.4, which is acidic.

(2) Mixing (slurrying) Separate 816 g of the above-mentioned alkaline germanium aqueous solution and heat it to 40°C while stirring. Add the above-mentioned acidic lithium, aluminum, phosphorus, and titanium-containing aqueous solution in full to it. The aqueous solution becomes white turbid immediately after the addition. A white slurry is obtained. The pH value of the obtained white slurry was 4.1.

(3) Amorphous Lithium Ion Conductive Oxide Powder Using the obtained white slurry, the same operation as in Example 1 was followed to obtain the amorphous lithium ion conductive oxide powder of Example 3. The composition formula of the obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ . Using the amorphous lithium ion conductor powder of Example 3, the XRD measurement was carried out in accordance with the same operation as in Example 1. As a result, halo was observed in the region of 2θ: 15°~40°. The half-value width of the halo 2θ: 2° or more.

Using the amorphous lithium ion conductor powder of Example 3, following the same operation as that of Example 1, the lithium ion conductive oxide powder of Example 3 was obtained, and a pressed powder calcined body of the lithium ion conductor was obtained. Using the compressed powder calcined body of the lithium ion conductor of Example 3, the XRD measurement was carried out according to the same operation as that of Example 1. As a result, it was found that the lithium ion conductive oxide powder of Example 3 was a lithium ion with a NASICON crystal structure. Conductive oxide powder (composition formula: Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ ).

<Example 4> (1) Preparation of raw material aqueous solution (I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 24.8 g of lithium nitrate, 57.9 g of aluminum nitrate nonahydrate, and 72.5 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 1.3, which is acidic.

(2) Mixing (slurrying) Dispense 600 g of the above alkaline germanium aqueous solution and heat it to 40°C while stirring. Add the above acidic lithium, aluminum, phosphorus, and titanium aqueous solution in full to it. The aqueous solution becomes white turbid immediately after the addition. A white slurry is obtained. The pH value of the obtained white slurry was 3.9.

(3) Amorphous Lithium Ion Conductive Oxide Powder Using the obtained white slurry, the same operation as in Example 1 was followed to obtain the amorphous lithium ion conductive oxide powder of Example 4. The composition formula of the obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ . Using the amorphous lithium ion conductor powder of Example 4, the XRD measurement was carried out in the same manner as in Example 1. As a result, halo was observed in the region of 2θ: 15°~40°. The half-value width of the halo 2θ: 2° or more.

Using the amorphous lithium ion conductor powder of Example 4, following the same operation as that of Example 1, the lithium ion conductive oxide powder of Example 4 was obtained, and a pressed powder calcined body of the lithium ion conductor was obtained. Using the compressed powder calcined body of the lithium ion conductor of Example 4, the XRD measurement was carried out according to the same operation as that of Example 1. As a result, it was found that the lithium ion conductive oxide powder of Example 4 was a lithium ion with a NASICON crystal structure. Conductive oxide powder (composition formula: Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ ).

<Example 5> (1) Preparation of raw material aqueous solution (I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 21.7 g of lithium nitrate, 39.4 g of aluminum nitrate nonahydrate, and 72.5 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 1.4, which is acidic.

(III) Titanium-containing aqueous solution After adding 3.0 g of ammonia water with a concentration of 28% by mass to 35.8 g of hydrogen peroxide water with a concentration of 35% by mass, 1.51 g of metatitanic acid was further added, and the mixture was stirred until it was completely dissolved. The aforementioned aqueous solution containing lithium, aluminum, and phosphorus is added to this solution. The pH value at this point is 4.0.

(2) Mixing (slurrying) Divide 684 g of the above alkaline germanium aqueous solution and heat it to 40°C while stirring. Add the above acidic lithium, aluminum, phosphorus, and titanium aqueous solution in full to it. The aqueous solution becomes white turbid immediately after the addition. A white slurry is obtained. The pH value of the obtained white slurry was 6.7.

(3) Amorphous Lithium Ion Conductive Oxide Powder Using the obtained white slurry, the same operation as in Example 1 was followed to obtain the amorphous lithium ion conductive oxide powder of Example 5. The composition formula of the obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 (Ge _1.4 Ti _0.1 )P _3.0 O ₁₂ . Using the amorphous lithium ion conductor powder of Example 5, the XRD measurement was carried out in accordance with the same operation as in Example 1. As a result, halo was observed in the region of 2θ: 15°~40°. The half-value width of the halo 2θ: 2° or more.

(I) Calculating the amount of oxygen The amount of oxygen in titanium contained in the amorphous lithium ion conductive oxide powder is calculated as follows. Tetravalent titanium oxide belonging to the TiO _2, and thus the amount of oxygen in the titanium oxide-based markers by the formula: Ti number of oxygen atoms of titanium oxide = (Ti concentration × (the formula weight of TiO ₂ / TiO ₂₎ is ÷Ti formula weight)-Ti concentration...(Formula) On the other hand, the ICP analysis result of titanium concentration is 0.8% by mass, so the following formula is established: Oxygen content of titanium oxide=(0.8×(79.88/1) ÷47.88)-0.8=0.53 mass%

The amorphous lithium ion conductor powder of Example 5 was calcined at 700° C. for 120 minutes to obtain a crystallized lithium ion conductor, and a pressed powder calcined body of the lithium ion conductor was obtained. The compressed powder calcined body of the lithium ion conductor was subjected to XRD measurement under the conditions described in the above "(V) XRD measurement of amorphous lithium ion conductive oxide powder", and compared with JCPDS card No.01-080-1922 Yes, the result is consistent with the crystal peak _{of LiGeP 3} O ₁₂ which is a lithium ion conductor with a NASICON crystal structure. From this, it was found that the pressed powder calcined body of the lithium ion conductive oxide powder of Example 5 is a lithium ion conductor having a NASICON crystal structure.

<Example 6> (1) Preparation of raw material aqueous solution (I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 21.7 g of lithium nitrate, 39.4 g of aluminum nitrate nonahydrate, and 72.5 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 0.9, which is acidic. (2) Mixing (slurrying) 684 g of the above-mentioned alkaline germanium aqueous solution was fractionated, heated to 40° C. while stirring, and 4.1 g of zirconyl nitrate was added to completely dissolve it. The entire amount of the acidic aqueous solution containing lithium, aluminum, and phosphorus was added thereto. As a result, the aqueous solution became cloudy immediately after the addition, and a white slurry was obtained. The pH value of the obtained white slurry was 3.9.

(3) Amorphous Lithium Ion Conductive Oxide Powder Using the obtained white slurry, the same operation as in Example 1 was followed to obtain the amorphous lithium ion conductive oxide powder of Example 5. The composition formula of the obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 (Ge _1.4 Zr _0.1 )P _3.0 O ₁₂ . Using the amorphous lithium ion conductor powder of Example 5, the XRD measurement was carried out in accordance with the same operation as in Example 1. As a result, halo was observed in the region of 2θ: 15°~40°. The half-value width of the halo 2θ: 2° or more.

(I) The amount of oxygen is calculated as follows. _{ZrO 2} belongs to the oxide system of tetravalent zirconium, so the oxygen content of zirconium oxide is marked by the following formula: Oxygen content of zirconium oxide = (Zr concentration × (ZrO ₂ formula weight / ZrO ₂ Zr atom number) ÷Zr formula weight)-Zr concentration...(Formula) On the other hand, the ICP analysis result of zirconium concentration is 1.5% by mass, so the following formula is established: Oxygen content of zirconium oxide=(1.5×(123.22/1) ÷91.22)-1.5=0.53 mass%

The amorphous lithium ion conductor powder of Example 6 was calcined at 700° C. for 120 minutes to obtain a crystallized lithium ion conductor, and a pressed powder calcined body of the lithium ion conductor was obtained. The compressed powder calcined body of the lithium ion conductor was subjected to XRD measurement under the conditions described in the above "(V) XRD measurement of amorphous lithium ion conductive oxide powder", and compared with JCPDS card No.01-080-1922 Yes, the result is consistent with the crystal peak _{of LiGeP 3} O ₁₂ which is a lithium ion conductor with a NASICON crystal structure. From this, it is found that the pressed powder calcined body of the lithium ion conductive oxide powder of Example 6 is a lithium ion conductor having a NASICON-type crystal structure.

<Example 7> (1) Preparation of raw material aqueous solution (I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 23.9 g of lithium nitrate, 39.4 g of aluminum nitrate nonahydrate, and 68.9 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 1.6, which is acidic.

(2) Mixing (slurrying) 720 g of the above-mentioned alkaline germanium aqueous solution was divided, and _{10.2 g of Li 2} O ₁₁ Si ₅ solution (manufactured by SIGMA-ALDRICH) was added. The solution was heated to 40°C while stirring, and the entire acidic aqueous solution containing lithium, aluminum, phosphorus, and titanium was added to the solution. The aqueous solution became cloudy immediately after the addition to obtain a white slurry.

(3) Amorphous Lithium Ion Conductive Oxide Powder Using the obtained white slurry, the same operation as in Example 1 was followed to obtain the amorphous lithium ion conductive oxide powder of Example 7. The composition formula of the obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 (P _2.96 Si _0.04 )O ₁₂ . Using the amorphous lithium ion conductor powder of Example 7, the XRD measurement was carried out in the same manner as in Example 1. As a result, halo was observed in the region of 2θ: 15°~40°. The half-value width of the halo was 2θ: 2° or more.

(I) Calculating the amount of oxygen The amount of oxygen in silicon contained in the amorphous lithium ion conductive oxide powder is calculated as follows. Tetravalent silicon oxide belonging to the SiO _2, and thus the amount of oxygen-based silicon oxide is labeled by the formula: = amount of oxygen in the silicon oxide (Si concentration × (SiO ₂ amount of Formula / SiO ₂ to the number of Si atoms) ÷Si formula weight)-Si concentration...(Formula) On the other hand, the ICP analysis result of silicon concentration is 0.2% by mass, so the following formula is established: Oxygen content of silicon oxide=(0.2×(60.08/1) ÷28.09)-0.2=0.23 mass%

The amorphous lithium ion conductor powder of Example 7 was calcined at 700° C. for 120 minutes to obtain a crystallized lithium ion conductor, and a pressed powder calcined body of the lithium ion conductor was obtained. The compressed powder calcined body of the lithium ion conductor was subjected to XRD measurement under the conditions described in the above "(V) XRD measurement of amorphous lithium ion conductive oxide powder", and compared with JCPDS card No.01-080-1922 Yes, the result is consistent with the crystal peak _{of LiGeP 3} O ₁₂ which is a lithium ion conductor with a NASICON crystal structure. From this, it is found that the pressed powder calcined body of the lithium ion conductive oxide powder of Example 7 is a lithium ion conductor having a NASICON crystal structure.

<Example 8> (1) Preparation of raw material aqueous solution (I) Germanium aqueous solution 192.5 g of germanium dioxide was added to 4000 g of pure water, heated to 40° C. while stirring, and 97.5 g of ammonia water with a concentration of 28% by mass as an alkali was added to prepare an aqueous germanium solution in which the germanium dioxide was dissolved. The pH value of the prepared aqueous solution is 10.7, which is alkaline.

(II) Aqueous solution containing lithium, aluminum and phosphorus 22.9 g of lithium acetate, 39.4 g of aluminum nitrate nonahydrate, and 72.5 g of ammonium dihydrogen phosphate were added to 150 g of pure water to prepare an aqueous solution containing lithium, aluminum, and phosphorus. The pH value of the prepared aqueous solution containing lithium, aluminum and phosphorus is 1.8, which is acidic.

(2) Mixing (slurrying) Divide 720 g of the above alkaline germanium aqueous solution and heat it to 40°C while stirring. Add the above acidic lithium, aluminum, phosphorus, and titanium aqueous solution in full to it. The aqueous solution becomes white turbid immediately after the addition. A white slurry is obtained. The pH value of the obtained white slurry was 4.5.

(3) Amorphous Lithium Ion Conductive Oxide Powder Using the obtained white slurry, the same operation as in Example 1 was performed to obtain the amorphous lithium ion conductive oxide powder of Example 8. The composition formula of the obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ . Using the amorphous lithium ion conductor powder of Example 8, the XRD measurement was carried out in the same manner as in Example 1. As a result, halo was observed in the region of 2θ: 15°~40°. The half-value width of the halo 2θ: 2° or more.

Using the amorphous lithium ion conductor powder of Example 8, following the same operation as that of Example 1, the lithium ion conductive oxide powder of Example 8 was obtained, and a pressed powder calcined body of the lithium ion conductor was obtained. Using the compressed powder calcined body of the lithium ion conductor of Example 8, the XRD measurement was carried out according to the same operation as that of Example 1. As a result, it was found that the lithium ion conductive oxide powder of Example 8 was a lithium ion with a NASICON crystal structure. Conductive oxide powder (composition formula: Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ ).

(Comparative example 1) According to the manufacturing process flow chart of the lithium ion conductive oxide powder of Comparative Example 1 shown in FIG. 5, the amorphous lithium ion conductive oxide powder of Comparative Example 1 was manufactured. Then, the lithium ion conductive oxide powder of Comparative Example 1 was subjected to analysis and characteristic evaluation.

(1) Preparation of germanium and aluminum solution 410 g of Ge (OEt) and 33.25 g of Al (OBt) were added to 97.68 g of butanol and dissolved to prepare Ge and Al solutions.

(2) Preparation of lithium and phosphorus solutions LiCOOCH ₃ : 2.61 g and (NH ₄ ) ₂ HPO ₄ : 9.098 g were added to 379.64 g of pure water, and dissolved to prepare a lithium and phosphorus solution.

(3) Mixing (solization) The above-mentioned germanium and aluminum solutions are mixed with the above-mentioned lithium and phosphorus solutions to obtain a mixed solution.

(4) Drying → vacuum drying The above-mentioned mixed solution was dried in an environment of 100°C, and then vacuum-dried at 110°C to obtain a powder.

(5) Calcination The powder obtained by the above-mentioned vacuum drying was calcined at 400° C. in a nitrogen environment to obtain an amorphous lithium ion conductive oxide powder of Comparative Example 1. The 30,000 times SEM photograph of the obtained amorphous lithium ion conductive oxide powder is shown in FIG. 2.

1mmZr球珠160g及IPA：94.32g裝填於珠磨機中，施行120分鐘粉碎，獲得經調整粒度的鋰離子傳導氧化物粉末。 (7)乾燥 將經調整粒度的鋰離子傳導氧化物粉末裝入乾燥機中，依100℃施行3小時乾燥，而除去IPA，獲得該比較例1的鋰離子傳導氧化物粉末。 該比較例1的鋰離子傳導氧化物粉末之體積基準累積50%粒徑(D₅₀ )，依Helos(分散壓5bar)進行測定，結果為1.5μm。(6) Crushing 40g of the amorphous lithium ion conductive oxide powder of Comparative Example 1, together with

160g of 1mmZr beads and 94.32g of IPA: were packed in a bead mill, and pulverized for 120 minutes to obtain lithium ion conductive oxide powder with adjusted particle size. (7) Drying The lithium ion conductive oxide powder with the adjusted particle size was put into a dryer, and dried at 100° C. for 3 hours to remove IPA, and the lithium ion conductive oxide powder of Comparative Example 1 was obtained. The volume-based cumulative 50% particle size (D ₅₀ ) of the lithium ion conductive oxide powder of Comparative Example 1 was measured by Helos (dispersion pressure 5 bar), and the result was 1.5 μm.

(8) Composition analysis of amorphous lithium ion conductive oxide powder The amorphous lithium ion conductive oxide powder of Comparative Example 1 was subjected to elemental analysis in the same manner as in Example 1, to obtain Li: 2.40 (mass%), Al: 2.94 (mass%), Ge: 25.2 (mass%), and P: 21.7 (mass%). The composition of each constituent element is shown in Table 2.

(9) Analysis of carbon content and oxygen content of amorphous lithium ion conductive oxide powder The carbon content and oxygen content in the amorphous lithium ion conductive oxide powder of Comparative Example 1 were measured in the same manner as in Example 1. As a result, the carbon content was 0.38% by mass, and the oxygen content was 44.5% by mass. The obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ . In addition, from the respective amounts of the aforementioned metal elements, phosphorus, carbon, and oxygen, the amount of impurities is calculated to be 2.9% by mass. This value is recorded in Table 2.

(10) Measurement of BET specific surface area of amorphous lithium ion conductive oxide powder The BET specific surface area of the amorphous lithium ion conductive oxide powder of Comparative Example 1 was measured in the same manner as in Example 1. The result was 12.3 m ² /g. This value is recorded in Table 3.

(11) XRD measurement of amorphous lithium ion conductive oxide powder With respect to the amorphous lithium ion conductive oxide powder of Comparative Example 1, XRD measurement was performed under the same measurement conditions as in Example 1. In the obtained XRD spectrum system, halo was confirmed in the same manner as in Example 1, and by this, it was confirmed that the lithium ion conduction system of Comparative Example 1 was amorphous. This matter is recorded in Table 3.

(12) Evaluation of ion conductivity of lithium ion conductive oxide powder with NASICON type crystal structure For the amorphous lithium ion conductive oxide powder of Comparative Example 1, the same operations as in Example 1 were performed to produce the amorphous lithium ion conductive oxide powder of Comparative Example 1. A pressed powder calcined body of lithium ion conductive oxide powder with a NASICON crystal structure. With respect to the produced compact calcined body of the lithium ion conductive oxide powder with the NASICON crystal structure of Comparative Example 1, the same ion conductivity calculation as in Example 1 was used, and the result was 4.6×10 ^-6 S/cm. This value is recorded in Table 3. Furthermore, the powder calcined body having a NASICON crystal structure of Comparative Example 1 was subjected to XRD measurement in the same manner as in Example 1. As a result, it was found that it belongs to a lithium ion conductor having a NASICON crystal structure.

(Comparative Example 2) According to the production process flow chart of the amorphous lithium ion conductive oxide powder of Comparative Example 2 shown in FIG. 6, the lithium ion conductive oxide powder of Comparative Example 2 (Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ ). Then, analysis and characteristic evaluation were performed on the prepared lithium ion conductive oxide powder of Comparative Example 2.

(1) Weighing of raw materials and mixed raw material powder system: Li ₂ CO ₃ : 2.85 g, Al ₂ O ₃ : 1.31 g, GeO ₂ : 8.08 _{g, NH 4} H ₂ PO ₄ : 17.76 g. Then, the weighed raw material powders are put into a ceramic mortar and mixed to obtain mixed powders.

(2) Calcination The obtained mixed powder was put into an alumina crucible, and calcined at a temperature of 400° C. for 5 hours in an atmosphere to obtain calcined powder.

(3) Melting The obtained calcined powder was put into a platinum crucible, and heated at a temperature of 1200°C for 1 hour to form a molten material.

(4)Quick cold The above-mentioned rapid cooling of the molten material is performed, vitrification is performed, and a powder of the glass body is obtained. The 10,000 times SEM photograph of the obtained glass body is shown in FIG. 2.

(5) Crush The powder of the obtained glass body is roughly crushed with a mortar to obtain a powder having a particle size of 200 μm or less. Then, in the same manner as in Example 1, the solvent IPA was used to perform wet pulverization to obtain an amorphous lithium ion conductive oxide powder with an adjusted particle size.

(6) Dry The lithium ion conductive oxide powder with the adjusted particle size was put into a dryer, and dried at 100° C. for 3 hours to remove IPA, and the amorphous lithium ion conductive powder of Comparative Example 2 was obtained.

(7) Composition analysis of amorphous lithium ion conductive oxide powder For the amorphous lithium ion conductive oxide powder of Comparative Example 2, elemental analysis was performed in the same manner as in Example 1. Li: 2.39 (mass%), Al: 2.98 (mass%), Ge: 24.5 (mass%), And P: 21.8 (mass%). The composition value of each constituent element is shown in Table 2.

(8) Analysis of carbon content and oxygen content of amorphous lithium ion conductive oxide powder The carbon content and oxygen content in the amorphous lithium ion conductive oxide powder of Comparative Example 2 were measured in the same manner as in Example 1. As a result, the carbon content was 0.041% by mass, and the oxygen content was 44.4% by mass. The obtained amorphous lithium ion conductive oxide powder is Li _1.5 Al _0.5 Ge _1.5 P _3.0 O ₁₂ . In addition, from the respective amounts of the aforementioned metal elements, phosphorus, carbon, and oxygen, the amount of impurities is calculated to be 3.9% by mass. This value is recorded in Table 2.

(9) Measurement of BET specific surface area of amorphous lithium ion conductive oxide powder The BET specific surface area of the amorphous lithium ion conductive oxide powder of Comparative Example 2 was measured in the same manner as in Example 1. The result was 3.3 m ² /g. This value is recorded in Table 3.

(10) XRD measurement of amorphous lithium ion conductive oxide powder With respect to the amorphous lithium ion conductive oxide powder of Comparative Example 2, XRD measurement was performed under the same measurement conditions as in Example 1. In the obtained XRD spectrum system, halo was confirmed in the same manner as in Example 1, and by this, it was confirmed that the amorphous lithium ion conduction system of Comparative Example 2 was amorphous. This matter is recorded in Table 3.

(11) Evaluation of ion conductivity of lithium ion conductive oxide powder with NASICON type crystal structure For the amorphous lithium ion conductive oxide powder of Comparative Example 2, the same operation as in Example 1 was performed to produce the comparative example 2 A pressed powder calcined body of lithium ion conductive oxide powder with a NASICON crystal structure. Regarding the pressed powder calcined body of the lithium ion conductive oxide powder having the NASICON crystal structure of Comparative Example 2 produced, the ion conductivity was calculated in the same manner as in Example 1, and the result was 2.2×10 ^-5 S/cm. This value is recorded in Table 3. Furthermore, the powder calcined body having a NASICON crystal structure of Comparative Example 2 was subjected to XRD measurement in the same manner as in Example 1. As a result, it was found that it belongs to a lithium ion conductor having a NASICON crystal structure.

[Table 2] Constituent elements Li Al Ge P Ti Zr Si Oxygen Carbon content Impurities (quality%) (quality%) (quality%) (quality%) (quality%) (quality%) (quality%) (quality%) (quality%) (quality%) Example 1 2.43 3.02 25.1 21.7 0.0 0.0 0.0 44.6 0.16 3.0 Example 2 2.08 1.86 28.8 21.3 0.0 0.0 0.0 44.2 0.12 1.6 Example 3 2.59 1.94 28.5 21.0 0.0 0.0 0.0 44.4 0.11 1.5 Example 4 3.04 4.74 21.5 22.4 0.0 0.0 0.0 46.1 0.26 1.9 Example 5 2.35 2.93 22.2 20.3 0.8 0.0 0.0 41.8 0.12 9.6 Example 6 2.40 2.99 22.2 20.7 0.0 1.5 0.0 42.4 0.18 7.6 Example 7 2.38 2.96 23.4 20.3 0.0 0.0 0.2 42.1 0.22 8.4 Example 8 2.35 3.10 23.9 20.7 0.0 0.0 0.0 42.7 0.30 6.9 Comparative example 1 2.40 2.94 25.2 21.7 0.0 0.0 0.0 44.5 0.38 2.9 Comparative example 2 2.39 2.98 24.5 21.8 0.0 0.0 0.0 44.4 0.04 3.9 [table 3] BET Cumulative 50% particle size Crystalline phase Ion conductivity (m ² /g) (μm) (S/cm) Example 1 27.7 1.8 Amorphous 6.4E-05 Example 2 24.2 1.7 Amorphous 5.2E-05 Example 3 25.0 1.5 Amorphous 5.7E-05 Example 4 25.4 1.8 Amorphous 6.1E-05 Example 5 31.0 1.8 Amorphous 4.0E-05 Example 6 24.0 1.7 Amorphous 3.8E-05 Example 7 45.0 1.9 Amorphous 4.3E-05 Example 8 26.3 1.6 Amorphous 3.8E-05 Comparative example 1 12.3 1.5 Amorphous 4.6E-06 Comparative example 2 3.3 1.6 Amorphous 2.2E-05 [Table 4] Device name XRD-6100 (manufactured by Shimadzu Corporation) Tube ball Cu Tube voltage 40kV Tube current 30mA Divergent slit 1.0° Scattering slit 1.0° Light receiving slit 0.3mm Step width 0.02°/step Measuring time 0.25sec

Fig. 1 is a flow chart showing the manufacturing steps of the lithium ion conductive oxide powder of the present invention. 2 is a 30,000 times SEM photograph of the lithium ion conductive oxide powder of Example 1, Comparative Examples 1 and 2. FIG. 3 is the XRD spectrum of the amorphous lithium ion conductive oxide powder of Example 1. FIG. FIG. 4 is an XRD spectrum of the lithium ion conductive oxide powder having a NASICON crystal structure of Example 1. FIG. FIG. 5 is a flowchart showing the manufacturing steps of the lithium ion conductive oxide powder of Comparative Example 1. FIG. FIG. 6 is a flowchart showing the manufacturing steps of the lithium ion conductive oxide powder of Comparative Example 2. FIG.

Claims (15)

An amorphous lithium ion conductive oxide powder containing: lithium: 0.5% by mass or more and 6.5% by mass or less, aluminum: more than 0% by mass and 25.0% by mass or less, germanium: more than 0% by mass and 65.0% by mass or less, Phosphorus: 10% by mass or more and 30% by mass or less; and the specific surface area measured by the BET single-point method is 15 m ² /g or more and 100 m ² /g or less. Such as the amorphous lithium ion conductive oxide powder of claim 1, which contains: Lithium: 1% by mass or more and 4% by mass or less, Aluminum: more than 0 mass% and 6 mass% or less, Germanium: More than 15% by mass and 35% by mass or less. Such as the amorphous lithium ion conductive oxide powder of claim 1 or 2, which further contains carbon: 0.01% by mass or more and 0.35% by mass or less. The amorphous lithium ion conductive oxide powder according to any one of claims 1 to 3, wherein the specific surface area measured by the BET single-point method is 20 m ² /g or more and 100 m ² /g or less. The amorphous lithium ion conductive oxide powder according to any one of claims 1 to 4, which further contains at least one element selected from titanium, zirconium, and hafnium. The amorphous lithium ion conductive oxide powder according to any one of claims 1 to 5, which further contains silicon: 10% by mass or less. The amorphous lithium ion conductive oxide powder of any one of claims 1 to 6, wherein the amorphous lithium ion conductive oxide powder is based on the general formula Li _1+x+w (Al _1-y M1 _y ) _x (Ge _1-z M2 _z ) _2-x P _3-w Si _w O ₁₂ formula, M1 is selected from gallium, lanthanum, indium and yttrium, and M2 is from titanium, zirconium and hafnium Choose one or more of them, the range of x is 0<x≦1.0, the range of y is 0≦y≦1.0, the range of z is 0≦z≦1.0, and the range of w is 0≦w≦1.0. The amorphous lithium ion conductive oxide powder according to any one of claims 1 to 6, which further contains at least one element selected from gallium, lanthanum, indium, and yttrium. A manufacturing method of amorphous lithium ion conductive oxide powder includes: A slurry forming step of mixing a lithium compound aqueous solution, an aluminum compound aqueous solution, a germanium compound aqueous solution, and an ammonium phosphate salt aqueous solution to obtain a coprecipitate suspension; The step of spray drying the slurry to obtain a dried slurry; and The above-mentioned dried slurry is calcined at a temperature above 300°C and below 500°C. The method for producing amorphous lithium ion conductive oxide powder according to claim 9, wherein, in the slurry forming step, an aqueous compound solution containing at least one element selected from gallium, lanthanum, indium, and yttrium is further mixed, and Obtain a co-precipitate suspension. The method for producing amorphous lithium ion conductive oxide powder according to claim 9 or 10, wherein, in the slurry forming step, an aqueous compound solution containing at least one element selected from titanium, zirconium, and hafnium is further mixed, and Obtain a co-precipitate suspension. The method for producing amorphous lithium ion conductive oxide powder according to any one of claims 9 to 11, wherein in the slurry forming step, an aqueous silicon compound solution is further mixed to obtain a coprecipitate suspension. The method for producing an amorphous lithium ion conductive oxide powder according to any one of claims 9 to 12, wherein the suspension in the slurry forming step is formed by mixing the germanium adjusted to a pH of 8 or higher Implementation of the compound aqueous solution. A method for manufacturing lithium ion conductive oxide powder with NASICON crystal structure, which includes: applying the amorphous lithium ion conductive oxide powder of any one of claims 1 to 8 at a temperature higher than 500°C Calcination step. A method for manufacturing lithium ion conductive oxide powder with NASICON crystal structure, including: A slurry forming step of mixing a lithium compound aqueous solution, an aluminum compound aqueous solution, a germanium compound aqueous solution, and an ammonium phosphate salt aqueous solution to obtain a coprecipitate suspension; The step of spray drying the slurry to obtain a dried slurry; and The above-mentioned dried slurry is calcined at a temperature higher than 500°C.

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