Method for producing garnet-type inorganic material

Abstract

The present invention relates to a method for producing a garnet-type inorganic material, and also to the garnet-type inorganic material itself. This method comprises the following steps: (1) contacting an aqueous solution S containing (i) a salt of zirconium, (ii) a salt of lanthanum, and (iii) a salt of element A or a precursor of an oxide of element A with an aqueous solution of a basic compound, thereby obtaining a precipitate suspended in the reaction medium; (2) stirring the reaction medium obtained at the end of step (1) for at least 30 minutes; (3) mixing the precipitate obtained at the end of step (2) with a surfactant selected from the group consisting of anionic surfactants, nonionic surfactants, polyethylene glycols, carboxylic acids and their salts, and carboxymethylated fatty alcohol ethoxylate type surfactants. (4) calcining the precipitate recovered at the end of the previous step in air at a temperature of at least 400°C; (5) contacting the product obtained at the end of step (4) with a salt of lithium; and (6) calcining the product obtained at the end of step (5) in air at a temperature of between 700°C and 1100°C, wherein the inorganic compound M comprises or essentially consists of a garnet oxide or garnet-type oxide containing, as constituent elements, the elements Li, La, Zr and at least one element A selected from the group consisting of Al, Ga, Nb, Fe, W, Ta, or mixtures thereof.

Description

Technical Field

[0001] This application claims the priority of European Patent Application No. 19315084.4 filed on August 6, 2019, the content of which is hereby incorporated by reference in its entirety for all purposes. In case there is any contradiction affecting the clarity of terms or expressions between this application and this European application, only this application shall be referred to.

[0002] The present invention relates to a method for manufacturing a garnet-type inorganic material. It also relates to the garnet-type inorganic material itself.

[0003] In recent years, as a promising material that can contribute to the development of all-solid-state lithium batteries, attention has been focused on garnet-type inorganic materials. In fact, J. Am. Ceram. Soc. 2003, volume 86, pages 437 to 440 reports that a garnet-type material of the formula Li5La3M2O 12 (where M is Nb or Ta) is a solid electrolyte material having excellent lithium ion conductivity.

[0004] Angew. Chem. Int. Ed. 2007, volume 46, pages 7778 to 7781 reports that another garnet-type material based on Li, Al, and Zr, of the formula Li7La3Zr2O 12 obtained by replacing Nb or Ta with Zr from Li5La3M2O 12 (hereinafter abbreviated as "LLZ"), is also a solid electrolyte material having excellent lithium ion conductivity.

[0005] Garnets have been known for a long time and originally correspond to orthosilicates of the formula A3B2(SiO4)3 where A and B represent cation sites with 8 - and 6 - coordination respectively. Lithium - containing garnets are obtained by replacing silicon with lithium to obtain a general composition of A3B2(LiO4)3. Since the garnet structure has the ability to accept a variety of atoms of different sizes and charges, numerous different Li - oxide garnets have been produced using Li at additional sites. In fact, it is possible to increase the lithium content by replacing A and / or B with cations in higher or lower oxidation states, resulting in a formula like Li7La3Zr2O 12 Lithium - containing garnets such as the promising solid - electrolyte material of Li7La3Zr2O

[0006] These two materials, Li5La3M2O 12 and Li7La3Zr2O 12 contain excess Li compared to the "ideal" garnet - type structure. Having this specific crystal structure is thought to be one of the reasons why these compounds exhibit high lithium - ion conductivity in the solid state. In particular, LLZ containing Al as a dopant has been found to exhibit a high lithium - ion conductivity of 10 -4 S / cm at room temperature.

[0007] Technical challenges For the manufacture of all - solid - state lithium secondary batteries, a method for producing LLZ garnet - type materials in particulate form is desired. In fact, the particles are used in the manufacture of electrode layers or separator layers. Particulates are required to enhance the contact with other components of the electrode layer or separator. In addition, the particulates also enable the manufacture of thin electrode layers and thin separators, which are usually advantageous for higher energy density.

[0008] Conventional methods of manufacturing LLZ garnet-type materials using solid-state reaction processes involve a calcination step at high temperatures of 1,000 to 1,200 °C (see, for example, Angew. Chem. Int. Ed. 2007, volume 46, pages 7778 to 7781, which discloses a calcination step at a temperature exceeding 1,000 °C). When calcination is carried out at such high temperatures, the growth of crystal grains is likely to be promoted, making it difficult to directly obtain fine particles. Furthermore, calcination at temperatures above 1,000 °C usually involves significant volatilization of lithium, which is a problem for the economy and environment of the process.

[0009] It is also necessary to obtain particles that can be easily dispersed in the solvents used for manufacturing electrodes and separators.

[0010] Therefore, there is a need for a method of manufacturing LLZ garnet-type materials in the form of fine and easily dispersible particles.

Background Art

[0011] Japanese Patent Application Laid-Open No. 2012-224520 discloses a method for manufacturing an LLZ garnet-type material by coprecipitation involving the use of a solution containing all elements including lithium.

[0012] U.S. Patent Application Publication No. 2018 / 0248223 and U.S. Patent Application Publication No. 2019 / 0051934 disclose methods for manufacturing LLZ garnet-type materials including coprecipitation using ammonia.

[0013] Japanese Patent Application Laid-Open No. 2012 / 224520, Japanese Patent Application Laid-Open No. 2013 / 256435, Japanese Patent Application Laid-Open No. 2018 / 065704, U.S. Patent Application Publication No. 2018 / 175446, and U.S. Patent Application Publication No. 2019 / 0036159 do not disclose the method of the present invention or the inorganic material M as the claimed invention.

Summary of the Invention

[0014] The present invention relates to an inorganic material M disclosed in any one of claims 1 to 22 or claim 30. It also relates to a method for producing the inorganic material M disclosed in any one of claims 23 to 29. It also relates to a composition (C), an electrode (E), or a separator (SP) disclosed in claims 31, 32, and 33, respectively. It also relates to the use of the inorganic material M disclosed in claim 34 and the use of a battery containing the inorganic material M disclosed in claim 35.

[0015] These objects will be further explained hereinafter.

[0016] The present invention The present invention (1) A step of contacting an aqueous solution S containing (i) a salt of zirconium, (ii) a salt of lanthanum, and (iii) a salt of element A or a precursor of an oxide of element A with an aqueous solution of a basic compound, as a result of which a precipitate suspended in the reaction medium is obtained; (2) A step of stirring the reaction medium obtained at the end of step (1) for at least 30 minutes; (3) A step of contacting the precipitate obtained at the end of step (2) with an additive selected from the group consisting of an anionic surfactant; a nonionic surfactant; polyethylene glycol; carboxylic acids and their salts; and a carboxymethylated fatty alcohol ethoxylate type surfactant; (4) A step of calcining the precipitate recovered at the end of the previous step in air at a temperature of at least 400 °C; (5) A step of contacting the product obtained at the end of step (4) with a salt of lithium; (6) A step of calcining the product obtained at the end of step (5) in air at a temperature of 700 °C to 1100 °C; A method for producing an inorganic material M, comprising: the inorganic compound M is an oxide containing, as constituent elements, element Li, La, Zr, and at least one element A selected from the group consisting of Al, Ga, Nb, Fe, W, Ta, or a mixture thereof.

[0017] The inorganic material M can be described as having a garnet structure. Therefore, in the context of the present invention, the oxide may be referred to as garnet or garnet-type oxide.

[0018] In step (1), an aqueous solution S containing (i) a zirconium salt, (ii) a lanthanum salt, and (iii) a salt of element A or a precursor of an oxide of element A is brought into contact with a solution of a basic compound.

[0019] The zirconium salt is preferably selected from the group consisting of zirconium nitrate and zirconium chloride. The zirconium salt may be, for example, zirconium nitrate or zirconyl nitrate. The zirconium salt may be crystalline zirconyl nitrate. This may be a solution of zirconium nitrate obtained by dissolving zirconium carbonate or zirconium hydroxide in nitric acid. The attack by this acid can preferably be carried out at an NO3 - / Zr molar ratio of 1.7 to 2.3. In the case of zirconium carbonate, this ratio may be 1.7 to 2.0.

[0020] The lanthanum salt may be lanthanum nitrate.

[0021] The source of the oxide of element A can be a salt of element A or a precursor of an oxide of element A. The source of element A may be a salt of element A such as iron nitrate, for example Fe(NO3)3, aluminum nitrate Al(NO3)3, or gallium nitrate Ga(NO3)3. The source of the oxide of element A can be a precursor of the oxide of element A such as a coordination complex of element A like niobium oxalate. The precursor of the oxide of element A can be an oxalate of element A. For example, the precursor of niobium oxide may be ammonium niobium oxalate.

[0022] Examples of the basic compound include a hydroxide type or carbonate type compound. The basic compound may be a hydroxide of an alkali metal or alkaline earth. The basic compound may also be ammonia, a secondary, tertiary, or quaternary amine. Ammonia is preferred because it provides a strong basic aqueous solution and can efficiently wash away the released ammonium salt.

[0023] Step (1) can be carried out by introducing aqueous solution S into the aqueous solution of the basic compound. On a laboratory scale, aqueous solution S can be introduced drop by drop, for example, into the aqueous solution of the basic compound. The duration of the introduction may be 30 minutes to 120 minutes, more specifically 30 minutes to 100 minutes.

[0024] Step (1) can be conveniently carried out at a temperature of 5°C to 40°C, more specifically 10°C to 30°C, and particularly 15°C to 25°C.

[0025] The amount of the basic compound used for the precipitation in step (1) is such that the pH of the mixture obtained at the end of step (1) is at least 7.0, more specifically at least 9.0. The amount of the basic compound used is such that the molar ratio r is higher than 1.0, more specifically 1.2 or more (≧1.2), and more specifically 1.4 or more (≧1.4), where r = the amount of the basic compound / the total amount of elements Zr, La, and A in solution S.

[0026] At the end of step (1), the reaction medium contains a precipitate dispersed in an aqueous medium.

[0027] In step (2), the reaction medium obtained at the end of step (1) is stirred for at least 30 minutes. According to one embodiment, the reaction medium is stirred for at least 30 minutes, and the temperature of the reaction medium is 50°C to 200°C, more specifically 80°C to 150°C. The duration of step (2) can be 30 minutes to 10 hours, more specifically 30 minutes to 5 hours, and even more specifically 1 hour to 5 hours. The reaction medium contains precipitates dispersed in an aqueous medium. Step (2) is conveniently carried out in a sealed container such as a stirred tank reactor.

[0028] In step (3), the precipitate obtained at the end of step (2) is contacted with an additive selected from the group consisting of an anionic surfactant; a nonionic surfactant; polyethylene glycol; carboxylic acid and its salts; and a carboxymethylated fatty alcohol ethoxylate type surfactant. Step (3) can be carried out by adding the additive to the dispersion of the precipitate in the aqueous medium obtained at the end of step (2). The additive has been found to be useful for obtaining an inorganic material M having a pure cubic phase (see Comparative Example 2).

[0029] Examples of anionic surfactants include sulfates such as ethoxycarboxylates, ethoxylated fatty acids, sarcosinates, phosphate esters, alcohol sulfates, alcohol ether sulfates and sulfated alkanolamide ethoxylates, as well as sulfosuccinates, and sulfonates such as alkylbenzene or alkylnaphthalene sulfonates. Examples of nonionic surfactants include acetylenic surfactants, alcohol ethoxylates, alkanolamides, amine oxides, ethoxylated alkanolamides, long-chain ethoxylated amines, ethylene oxide / propylene oxide copolymers, sorbitan derivatives, ethylene glycol, propylene glycol, glycerol, polyglyceryl esters and their ethoxylated derivatives, alkylamines, alkylimidazolines, ethoxylated oils and alkylphenol ethoxylates. Products sold under the brands Igepal®, Dowanol®, Rhodamox® and Alkamide® can be specifically mentioned.

[0030] Regarding carboxylic acids, in particular, aliphatic monocarboxylic acids or dicarboxylic acids, and among these, more particularly saturated acids can be used. Fatty acids, more particularly saturated fatty acids, may also be used. Thus, in particular, formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid and palmitic acid can be mentioned. Examples of dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid. Salts of carboxylic acids, particularly ammonium salts, can also be used. The addition may more specifically be lauric acid or ammonium laurate.

[0031] Finally, it is possible to use a surfactant selected from carboxymethylated fatty alcohol ethoxylate types. The expression "carboxymethylated fatty alcohol ethoxylate type product" is intended to mean a product consisting of an ethoxylated or propoxylated fatty alcohol containing a -CH2-COOH group at the end of the chain. These products can correspond to the formula: R1-O-(CR2R3-CR4R5-O) n -CH2-COOH (wherein, R1 means a saturated or unsaturated carbon-based chain usually having a maximum of 22 carbon atoms, preferably at least 12 carbon atoms; R2, R3, R4 and R5 may be the same and may represent hydrogen, or R2 may represent an alkyl group, for example, a CH3 group, and R3, R4 and R5 represent hydrogen; n is a non-zero integer which may be at most 50, more specifically may be 5 to 15, and these values are included). It is noted that the surfactant may consist of a mixture of products of the above formula where R1 may be saturated or unsaturated respectively, or alternatively a mixture of products containing both -CH2-CH2-O- groups and -C(CH3)=CH2-O- groups.

[0032] The additive can be added as such, or as a suspension or a solution in a liquid medium.

[0033] The amount of the additive added is expressed as the ratio of the weight of the additive to the weight of the inorganic material M (weight of additive / weight of inorganic material M × 100), and is usually 5% to 100%, more specifically 15% to 60%, preferably 30% to 50%. This amount may be as in Example 1 (additive / inorganic material M = 40%).

[0034] This process can also include step (3a) after step (3), where the solid obtained at the end of step (3) is washed with water. In step (3a), a basic aqueous solution (for example, an ammonia solution) can be used simply. The pH of the basic aqueous solution may be at least 8.0.

[0035] In step (4), the precipitate obtained at the end of the previous step (i.e., either step (3) or step (3a)) is calcined in air at a temperature of at least 400°C. The temperature needs to be high enough to at least partially cause the decomposition of the additive and the release of nitrates. The product obtained at the end of step (4) preferably contains less than 2.0 wt% of residual carbon. In practice, the calcination temperature may be 400°C to 800°C, more specifically, 400°C to 600°C. The higher the temperature, the more likely it is to induce some sintering that tends to reduce the specific surface area of the resulting product. The calcination time depends on the calcination temperature. This is generally 30 minutes to 10 hours, more specifically 1 hour to 5 hours.

[0036] In step (5), the product obtained at the end of the calcination step (4) is brought into contact with a lithium salt. A convenient way to carry out step (5) is to impregnate the product obtained at the end of the calcination step (4) with an aqueous solution of a lithium salt. More specifically, the aqueous solution of the lithium salt can be added drop by drop onto the solid while stirring. The lithium salt may be, for example, lithium chloride, lithium carbonate, lithium hydrogen carbonate, lithium nitrate, or lithium sulfate. The lithium salt can also be selected from the group of lithium carboxylates such as lithium acetate, lithium citrate, or lithium oxalate. Another convenient way to carry out step (5) is to mix together, both in powder form, the product obtained at the end of the calcination step (4) and the lithium salt.

[0037] The amount of lithium added should preferably be slightly more than the stoichiometric amount to account for some loss of lithium during the calcination step (6). Thus, the molar ratio of the amount of lithium added / the stoichiometric amount of lithium can be 1.00 to 1.20, more specifically, 1.05 to 1.15.

[0038] In step (6), the product obtained at the end of step (5) is calcined in air at a temperature of 700 °C to 1100 °C. The calcined product contains all the elements of the inorganic material M. The duration of calcination may be 2 hours to 15 hours, more specifically 4 to 10 hours.

[0039] In a specific embodiment of step (6), the product obtained at the end of step (5) is first calcined in air at a temperature of 700 °C to 900 °C and then calcined in air at a temperature of 900 °C to 1100 °C. In this two-stage calcination, the duration of each calcination may be 4 hours to 8 hours. In another specific embodiment of step (6), the product obtained at the end of step (5) is calcined in air at a temperature of 750 °C to 850 °C for a calcination time of 4 to 8 hours.

[0040] The calcination step (6) is conveniently carried out in a crucible. When the crucible is made of alumina, some aluminum atoms may migrate to the inorganic material M. Thereby, an inorganic material M containing a combination of Al and at least one other element A selected from the group consisting of Ga, Nb, Fe, W, Ta can be prepared.

[0041] The inorganic material obtained at the end of step (6) is recovered.

[0042] Regarding the inorganic material M The inorganic material M contains or consists essentially of the oxides disclosed above. The inorganic material M exhibits a cubic crystal structure and contains, as constituent elements, element Li, La, Zr and at least one element A selected from the group consisting of Al, Ga, Nb, Fe, W, Ta, or a mixture thereof, and contains or consists essentially of a garnet oxide or garnet-type oxide.

[0043] The garnet oxide or garnet-type oxide can be represented by formula (I): [Li x1 La3Zr z A w O 12 (I) (wherein, ·x1, z, and w are positive real numbers; ·1.20 < z ≤ 2.10; preferably 1.20 < z ≤ 2.05; preferably 1.50 ≤ z ≤ 2.00; ·0 < w ≤ 0.80; preferably 0 < w ≤ 0.60; more preferably 0 < w ≤ 0.30; even more preferably, 0 < w ≤ 0.25; ·x1 is derived from the electrical neutrality of the oxide).

[0044] A represents at least one element selected from the group consisting of Al, Ga, Nb, Fe, W, Ta, or a mixture thereof; more specifically, at least one element selected from the group consisting of Al, Ga, Nb, or a mixture thereof. A can also be selected from the group consisting of W, Ta, Ga, Nb, or a mixture thereof. In a particular embodiment, the inorganic material M comprises a combination of Al and another element A selected from the group consisting of Ga, Nb, Fe, W, and Ta.

[0045] z can be one of the following ranges: 1.20 < z ≤ 2.10; preferably 1.20 < z ≤ 2.05; preferably 1.50 ≤ z ≤ 2.00. More specifically, 1.90 ≤ z ≤ 2.10. Even more specifically, z ≤ 2.00.

[0046] w can be one of the following ranges: 0 < w ≤ 0.80; preferably 0 < w ≤ 0.60; more preferably 0 < w ≤ 0.30; even more preferably 0 < w ≤ 0.25. More specifically, w ≥ 0.05.

[0047] x1 is derived from the electrical neutrality of the oxide. For this purpose, the ratio of the constituent elements of the oxide other than lithium and the degree of oxidation of said elements are taken into account. Further, the following oxidation degrees are used: Li+I; Zr+IV; Hf+IV; La+III; Al+III; Ga+III; Nb+V; Fe+III; W+VI; Ta+V. As an example, in the case of the oxide of Example 1, since z = 1.99; w = 0.22, x1 = 6.38 (x1 = 24 - 3x3 - 4x1.99 - 3x0.22).

[0048] The inorganic material M and the oxide exhibit a cubic crystal structure. The cubic crystal structure can be determined by XRD. The cubic crystal structure is typically represented by the Ia-3d space group, and in some cases, the I-43d space group, especially when A = Ga, Fe, or Al+Ga.

[0049] The crystal structure of the oxide is usually composed of a framework of 8-coordinated LaO8 dodecahedra and 6-coordinated ZrO6 octahedra. More specifically, it may be composed of a framework of 8-coordinated LaO8 dodecahedra (24c) and 6-coordinated ZrO6 octahedra (16a).

[0050] The relative composition of the cations in the inorganic material M corresponds to the following formula: Li x La3Zr z A w (II) (where ·A is as disclosed above; ·w, x, z are positive real numbers; ·Z and w are as disclosed above; ·4.00 ≦ x ≦ 10.5; preferably 5.10 ≦ x ≦ 9.1; more preferably 6.20 ≦ x ≦ 7.7).

[0051] More specifically, the relative composition of the cations may be as follows: ·A is selected from the group consisting of Nb, Ta, or a combination thereof; ·1.20 < z ≦ 2.10; preferably 1.20 < z ≦ 2.05; preferably 1.50 ≦ z ≦ 2.00; ·0.10 < w ≦ 0.80; preferably 0.20 < w ≦ 0.80; more preferably, 0.20 < w ≦ 0.50; ·6.20 ≦ x ≦ 10.35; preferably 6.20 ≦ x ≦ 8.84; more preferably 6.50 ≦ x ≦ 7.48.

[0052] More specifically, the relative composition of the cations may be as follows: ·A is W; ·1.20 < z ≤ 2.10; preferably 1.20 < z ≤ 2.05; preferably 1.50 ≤ z ≤ 2.00; ·0.10 < w ≤ 0.80; preferably 0.20 < w ≤ 0.80; more preferably, 0.20 < w ≤ 0.50; ·5.40 ≤ x ≤ 10.20; preferably 5.40 ≤ x ≤ 8.58; more preferably 6 ≤ x ≤ 7.26.

[0053] More specifically, the relative composition of the cations may be as follows: ·A is selected from the group consisting of Al, Ga, Fe, or combinations thereof; ·1.90 < z ≤ 2.10; preferably 1.95 ≤ z ≤ 2.05; preferably 1.95 ≤ z ≤ 2.00; ·0.10 < w ≤ 0.80; preferably 0.20 < w ≤ 0.60; more preferably, 0.10 < w ≤ 0.25; ·4.60 ≤ x ≤ 10.05; preferably 5.20 ≤ x ≤ 8.32; more preferably 6.25 ≤ x ≤ 7.37.

[0054] According to one embodiment, the relative composition of the cations in the inorganic material M may also correspond to the following formula: Li x La3Zr z A1 w1 A2 w2 (IIa) (wherein, ·A1 is selected from the group consisting of Al, Ga, Fe, or combinations thereof; ·A2 is selected from the group consisting of Nb, Ta, or combinations thereof; ·w1, w2, x, and z are positive real numbers; ·1.20 < z ≤ 2.10; preferably 1.20 < z ≤ 2.05; preferably 1.50 ≤ z ≤ 2.00; ·0 < w1 ≤ 0.20; ·0.10 < w2 ≤ 0.80; preferably 0.20 < w2 ≤ 0.80; more preferably, 0.20 < w2 ≤ 0.50; ·w1 and w2 are such that w = w1 + w2 and w ≤ 0.80; ·5.60 ≤ x ≤ 10.35; preferably 5.60 ≤ x ≤ 8.84; more preferably 5.90 ≤ x ≤ 7.48).

[0055] More specifically, according to formula (IIa), A1 = Al. More specifically, according to formula (IIa), A2 = Nb.

[0056] According to one embodiment, the relative composition of cations in the inorganic material M can also correspond to the following formula: Li x La3Zr z A1 w1 A2 w2 (IIb) (wherein, ·A1 is selected from the group consisting of Al, Ga, Fe, or combinations thereof: ·A2 is W; ·w1, w2, x, and z are positive real numbers; ·1.20 < z ≤ 2.10; preferably 1.20 < z ≤ 2.05; preferably 1.50 ≤ z ≤ 2.00; ·0 < w1 ≤ 0.20; ·0.10 < w2 ≤ 0.80; preferably 0.20 < w2 ≤ 0.80; more preferably, 0.20 < w2 ≤ 0.50; ·w1 and w2 are such that w = w1 + w2 and w ≤ 0.80; ·4.80 ≤ x ≤ 10.20; preferably 4.80 ≤ x ≤ 8.58; more preferably 5.40 ≤ x ≤ 7.26).

[0057] More specifically, according to formula (IIb), A1 = Al.

[0058] The composition of the inorganic material M, and as a result x, z, w, w1, and w2 can be determined by chemical analysis using analytical techniques well-known to those skilled in the art. A convenient method for determining the composition of the inorganic material M, and as a result x, z, w, w1, and w2, consists of preparing an aqueous solution obtained by chemical attack of the inorganic material M and determining the elemental content in the aqueous solution by said analytical techniques. A convenient analytical method is ICP, more specifically ICP-MS (Inductively Coupled Plasma-Mass Spectrometry) or ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry).

[0059] In the context of the present invention, it must be noted that x≧x1. This is explained by the fact that the element lithium is usually added in excess in step (5) of the process in order to take into account some potential losses at the high temperature of the firing in step (6). As an example of this difference, the relative composition of the cations of the inorganic material M of Example 1 analyzed by ICP is Li 6.44 La3Zr 1.99 Al 0.22 (x = 6.44), while the oxide is Li 6.38 La3Zr 1.99 Al 0.22 O 12 (x1 = 6.38) in composition.

[0060] The lithium cations are located within the crystal structure, but may also be located outside the crystal structure. The oxide crystal contains LiO4 tetrahedra and LiO6 octahedra. More specifically, as outlined in Chem. Lett. 2011, 40, 60-62, Li + within the crystal is located at the interstitial site and is generally described as exhibiting tetrahedra (24d), octahedra (48g), and distorted four-coordination (96h).

[0061] Therefore, the inorganic material M may also contain lithium cations outside the crystal structure. Therefore, the inorganic material M may also contain anions other than O2 - in order to ensure the electrical neutrality of the inorganic material M. O2 -The anions other than those may be, for example, hydroxide or carbonate.

[0062] It should be noted that Zr is usually associated with Hf in the ore from which Zr is extracted. Therefore, the present invention is also applicable to the inorganic material M and the oxide in which Zr is partially replaced by Hf. The molar ratio Hf / Zr is usually 1 / 100 to 5 / 100, more specifically 1 / 100 to 2 / 100.

[0063] The particles of the inorganic material M are composed of finer particles than those prepared by conventional solid-phase chemistry. The finer the particles, the more easily they are dispersed in a conventional solvent (such as NMP) used for fabricating an electrode or a separator. They also ensure more intimate contact between the particles and other components of the electrode or separator.

[0064] The particles of the inorganic material M usually exhibit a D50 of 10.0 to 50.0 μm, more specifically 10.0 to 40.0 μm, and even more specifically 10.0 to 35.0 μm.

[0065] The particles of the inorganic material M may also exhibit a D90 of usually less than 150.0 μm. The D90 may be 20.0 to 150.0 μm, more specifically 20.0 to 100.0 μm.

[0066] The particles of the inorganic material M may also exhibit a D10 of usually 0.5 μm or more. The D10 may be 0.5 to 15.0 μm, more specifically 0.5 to 10.0 μm.

[0067] By this process, an inorganic material M that can be easily deflocculated can be obtained. After treatment under ultrasonic waves, the particles of the inorganic material M usually exhibit a D US 50. This D US50 may be from 0.5 μm to 15.0 μm, more specifically from 0.5 μm to 10.0 μm, and even more specifically from 1.0 μm to 10.0 μm. The treatment under ultrasonic waves consists of inserting an ultrasonic probe into a dispersion of 100 mg of inorganic material M in 160 mL of NMP and subjecting the dispersion to ultrasonic treatment at an output of 140 ± 10 W for 22 minutes. The temperature of the dispersion is preferably kept below 45°C, more specifically below 30°C.

[0068] After the treatment under ultrasonic waves, the particles of inorganic material M usually have a D of 30.0 μm or less, more specifically 20.0 μm or less, and even more specifically 15.0 μm or less. US 90 is shown.

[0069] Therefore, the particles of inorganic material M show large fluctuations in D50 and D90 after the treatment under ultrasonic waves. D50 and D90 decrease with time during the ultrasonic treatment. However, it has been observed that these two parameters tend to stabilize before the ultrasonic treatment ends. Therefore, D90 > D US 50 and D90 > D US 90. The fluctuations in D50 and D90 can be confirmed by the following two ratios: R50(%) = (D50 - D US 50) / D50 × 100 R90(%) = (D90 - D US 90) / D90 × 100

[0070] R50 may be more than 50%, more specifically more than 60%, and even more specifically more than 70% or more than 80%. R90 may be more than 50%, more specifically more than 60%, and even more specifically more than 70% or more than 80%.

[0071] As shown in the examples, by the method of the present invention, it is possible to obtain an inorganic material M showing an R50 of more than 70% and / or an R90 of more than 70%. It is also possible to obtain an R50 of more than 80% and / or an R90 of more than 80%.

[0072] D10, D50, and D90 have their ordinary meanings used in the field of particle size distribution. For example, see https: / / www.horiba.com / fileadmin / uploads / Scientific / Documents / PSA / PSA_Guidebook.pdf. Thus, Dn corresponds to the diameter of the particles such that n% of the particles have a diameter smaller than Dn. Thus, D50 is the median diameter. These parameters are determined from the volume distribution of the diameters of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained with a laser diffractometer. When D50 is measured after treatment of the dispersion of the particles in NMP under ultrasound, it is denoted as D US 50. Similarly, when D90 is measured after treatment of the dispersion of the particles in NMP under ultrasound, it is denoted as D US 90.

[0073] A laser diffractometer measures the size of particles by measuring the intensity of the light scattered when a laser beam passes through a dispersed particle sample using the technique of laser diffraction. The laser diffractometer can be a Mastersizer 3000 manufactured by Malvern (see https: / / www.malvernpanalytical.com / en / products / product-range / mastersizer-range / mastersizer-3000).

[0074] The particles of the inorganic material M (“secondary particles”) are aggregates formed by the aggregation of other finer particles, later called “primary particles”. The primary particles exhibit a d50 of 0.5 μm to 7.0 μm, more specifically 0.5 μm to 5.0 μm, and even more specifically 0.5 μm to 3.0 μm.

[0075] d50 is obtained from a statistical analysis performed on the distribution (number) of the diameters d of the primary particles, and these diameters are determined from at least one photograph obtained by SEM (scanning electron microscope). In the case of D50, d50 corresponds to the median diameter of the distribution. To make it meaningful, the statistical analysis is preferably performed on a large number of particles. This is usually done with multiple photographs of the same sample of the inorganic material M particles. The number of particles considered for the statistical analysis is preferably more than 70, more specifically more than 100, and even more preferably more than 200.

[0076] d50 is measured in an observation performed at a magnification suitable for well observing the primary particles and secondary particles. The magnification can be from ×1000 to ×10000. Of course, the magnification varies depending on the sample and needs to be selected on a case-by-case basis. The observation can be performed either by (i) image analysis or (ii) an operator. When the particles are integrally bonded to each other, observation by an operator is recommended.

[0077] The diameter d of the primary particles to be retained is the diameter of a circle circumscribing the image of the primary particles visible in the photograph. Only the primary particles with at least half of their surroundings defined are retained. Preferably, the circle should have the contour of the primary particles in contact with at least one-third of its circumference.

[0078] By the method of the present invention, an inorganic material M showing a pure cubic crystal structure can be obtained. It should be understood that the expression "pure cubic crystal structure" means that the inorganic material M contains a tetragonal crystal phase at a ratio of less than 5.0%. This also includes a cubic crystal phase at a ratio exceeding 95.0%. These ratios can be easily obtained using XRD (X-ray diffraction), more specifically Rietveld analysis. The tetragonal crystal phase is known to belong to the I 41 / acd space group.

[0079] The method of the present invention also makes it possible to obtain an inorganic material M with a low amount of undesirable compound of the formula La2Zr2O7. In fact, the inorganic material M preferably exhibits an intensity ratio (b / a) of less than 0.05. a and b are the intensities of the peaks appearing in the XRD diagram at 2θ of 16.0° to 17.0° and 2θ of 28.5° to 28.7°, respectively. The higher the intensity ratio (b / a), the more La2Zr2O7 present as an impurity phase. It is considered that more La2Zr2O7 exists as an impurity at a higher calcination temperature. The ratio (b / a) can further be less than 0.02, or less than 0.01. This can be included in the range of 0.001 to 0.05, more specifically 0.001 to 0.02.

[0080] Regarding the use of the inorganic material M The inorganic material M disclosed above can be used in the manufacture of lithium-ion batteries. Accordingly, the present invention also relates to a lithium-ion battery containing the inorganic material M.

[0081] The inorganic material M disclosed above can be used in the manufacture of the electrode E. The electrode E can be a positive electrode (represented as E p ), or a negative electrode (represented as E n ).

[0082] The electrode E of the present invention typically comprises · a metal substrate; · at least one layer L directly adhered onto the metal substrate, (i) the inorganic material M disclosed herein, (ii) at least one electroactive compound (EAC), (iii) optionally, at least one lithium-ion conducting material (LiCM) other than the inorganic material M, (iv) optionally, at least one conductive material (ECM), (v) optionally, a lithium salt (LIS), (vi) optionally, at least one polymeric binder material (P), and a layer L produced from a composition (C) containing including.

[0083] The term "electroactive compound" (EAC) is intended to mean a compound that can incorporate or insert and release lithium ions into its structure during the charging and discharging stages of an electrochemical device. Thus, an EAC is a compound that can insert and desorb lithium ions into its structure. The properties of the EAC depend on whether the electrode is a positive electrode or a negative electrode.

[0084] 1) Positive electrode E p The EAC may be a complex metal chalcogenide of the formula LiMeQ2, where - Me is at least one metal selected from the group consisting of Co, Ni, Fe, Mn, Cr, Al, and V; - Q is a chalcogen such as O or S.

[0085] More specifically, the EAC may be of the formula LiMeO2. Preferred examples of the EAC include LiCoO2, LiNiO2, LiMnO2, LiNi x Co 1-x O2 (0 < x < 1), LiNi x Co y Mn z O2 (0 < x, y, z < 1 and x + y + z = 1), Li(Ni x Co y Al z )O2 (x + y + z = 1), and spinel-structured LiMn2O4 and Li(Ni 0.5 Mn 1.5 )O4.

[0086] The EAC may also be an electroactive material based on a lithiated or partially lithiated transition metal oxyanion of the formula M1M2(JO4) f E 1-f , where - M1 is lithium, which may be partially substituted by another alkali metal that occupies less than 20% of M1; - M2 is a transition metal with an oxidation level of +2 selected from Fe, Mn, Ni, or mixtures thereof, which may be partially substituted by one or more additional metals having an oxidation level between +1 and +5 and accounting for less than 35% of the M2 metal, including 0; - JO4 is any oxyanion, and J is any of P, S, V, Si, Nb, Mo, or combinations thereof; - E is a fluoride, hydroxide, or chloride anion; - f is the mole fraction of the JO4 oxyanion generally included between 0.75 and 1.

[0087] M1M2(JO4) as defined above f E 1-f The electroactive material is preferably phosphate-based. This may exhibit an ordered structure or a modified cancrinite structure.

[0088] EAC may be sulfur or Li2S.

[0089] 2) Negative electrode E n In that case, EAC can be selected from the group consisting of graphite carbon into which lithium can be inserted. Details of this type of EAC can be found in Carbon 2000, 38, 1031 - 1041. This type of EAC typically exists in the form of powder, flakes, fibers, or spheres (e.g., mesocarbon microbeads).

[0090] EAC is lithium metal; a lithium alloy composition (e.g., those described in U.S. Patent No. 6,203,944 and International Publication No. 00 / 03444 pamphlet); lithium titanate generally represented by the formula Li4Ti5O 12 ; (these compounds are generally regarded as "zero strain" insertion materials that physically expand at a low level when taking in mobile ions, i.e., Li + ); lithium-silicon alloys, especially those of the formula Li 4.4Lithium silicide of Si; formula Li 4.4 A lithium-germanium alloy containing a crystalline phase of Ge; may also be used.

[0091] The ECM is typically selected from the group consisting of a conductive carbonaceous material and a metal powder or fiber. The conductive carbonaceous material can be selected, for example, from the group consisting of carbon black, carbon nanotubes, graphite, graphene, and graphite fibers, and combinations thereof. Examples of carbon black include Ketjen black and acetylene black. Examples of the metal powder or fiber include powders or fibers of nickel and aluminum.

[0092] The lithium salt (LIS) can be selected from the group consisting of LiPF6, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, LiB(C2O4)2, LiAsF6, LiClO4, LiBF4, LiAlO4, LiNO3, LiCF3SO3, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiC(SO2CF3)3, LiN(SO3CF3)2, LiC4F9SO3, LiCF3SO3, LiAlCl4, LiSbF6, LiF, LiBr, LiCl, LiOH, and lithium 2-trifluoromethyl-4,5-dicyanoimidazole.

[0093] The function of the polymer-based binder is to hold the components of composition (C) together. The polymer-based binder is usually inert. This is preferably chemically stable and also needs to facilitate electron and ion transport. Polymer-based binders are well-known in the art. Non-limiting examples of polymer-based binders include, in particular, vinylidene fluoride (VDF)-based (co)polymers, styrene-butadiene rubber (SBR), styrene-ethylene-butylene-styrene (SEBS), carboxymethyl cellulose (CMC), polyamideimide (PAI), poly(tetrafluoroethylene) (PTFE), and poly(acrylonitrile) (PAN) (co)polymers. This is preferably a fluoropolymer, more specifically a VDF-based (co)polymer containing repeating units derived from VDF. The VDF-based (co)polymer may be, for example, polyvinylidene fluoride or a copolymer of VDF and at least one fluorinated monomer different from VDF such as hexafluoropropylene (HFP).

[0094] The proportion of the inorganic material M in the composition (C) may be from 0.1% by weight to 80.0% by weight based on the total weight of the composition. In particular, this proportion may be from 1.0% by weight to 60.0% by weight, more specifically from 10.0% by weight to 50.0% by weight. The thickness of the electrode (E) is not particularly limited and needs to be adjusted according to the energy and output required for the application. For example, the thickness of the electrode (E) may be from 0.01 mm to 1,000 mm.

[0095] The inorganic material M can also be used in the production of the separator (SP). The separator is a permeable membrane disposed between the anode and the cathode of the battery. Its function is to block electrons and ensure physical separation between the electrodes while allowing lithium ions to permeate. The separator (SP) of the present invention typically comprises · the inorganic material M; · an optional at least one polymer-based binder (P); · an optional at least one metal salt, particularly a lithium salt; ·At least one optional plasticizer; comprises.

[0096] The electrode (E) and the separator (SP) can be manufactured using methods well known to those skilled in the art. This typically involves mixing the components in a suitable solvent and then removing the solvent. For example, the electrode (E) can be prepared by a process comprising the following steps: - Applying a slurry comprising the components of the composition (C) and at least one solvent to a metal substrate; - Removing the solvent.

[0097] Common techniques known to those skilled in the art are as follows: coating and calendaring, dry and wet extrusion, 3D printing, sintering of porous foams and subsequent impregnation. The common techniques for fabricating the electrode (E) and the separator (SP) are shown in Energy Environ.Sci., 2019, 12, 1818.

Example

[0098] X-ray diffraction The XRD diffraction pattern of the powder was obtained using a Cu X-ray tube (Cu Kalpha with a wavelength of 1.5406 Å) on an XRD goniometer with Bragg Brentano geometry. The setup can be used with various optical configurations, i.e., variable or fixed divergence slits, or solar slits. Primary filtering devices such as Panalytical's monochromator or Bragg Brentano HD optics can also be used. When a variable divergence slit is used, the typical irradiation area is 10 mm × 10 mm. The sample holder is loaded onto a spinner, and the rotation speed during acquisition is typically 60 rpm. The tube settings were operated at 40 kV / 30 mA for variable slit acquisition and 45 kV / 40 mA for fixed slit acquisition using the incident Bragg Brentano HD optics. The acquisition step was 0.017° per step. The angular range was typically 5° - 90° with 2 theta or more. The total acquisition time was typically 30 minutes or more.

[0099] The Rietveld analysis was performed using the pseudo-Voigt profile function of Thompson et al. (P. Thompson, D. E. Cox, J. B. Hastings, J. Appl. Cryst., 20 (1987), pp. 79-83). The cubic LLZO phase was indexed in the Ia-3d space group, and the atomic positions and occupancies were reported. The zero shift, unit cell parameters, scale factor, isotropic size, and microstrain broadening of the sample were refined with a model. The instrumental resolution function (IRF) was obtained from a well-crystallized LaB6 sample.

[0100] For the determination of b / a, the intensity was determined from the diffraction pattern with reference to the baseline obtained in the 2θ angle range of 5.0° to 90.0°. The baseline was automatically determined using software for analyzing the diffraction pattern data.

[0101] Determination of d50 As outlined above, d50 is obtained from a statistical analysis of the distribution (number) of the diameters d of the primary particles, and these diameters are determined from at least one photograph obtained by SEM (scanning electron microscope). The scanning electron microscope must be properly aligned and adjusted according to the guidelines provided by the manufacturer. Furthermore, a certified reference material can be used to confirm that the measured diameters match the actual ones. d50 is determined from the cumulative particle size distribution of the diameter d.

[0102] Determination of D10, D50, and D90 These parameters were obtained by laser diffraction using a Malvern Mastersizer 3000. The sample was dispersed in NMP. Mie theory was used for the analysis of the raw data. The following parameters were used: - For the inorganic material M: a refractive index of 2.15 and an absorption rate of 0.01; - For NMP: a refractive index of 1.46.

[0103] D US 50 and DUS Determination of 90 These parameters were obtained by laser diffraction under the same conditions as those disclosed above after treatment under ultrasonic waves. The treatment under ultrasonic waves consists of inserting an ultrasonic probe into a dispersion of 100 mg of inorganic material M in 160 mL of NMP and subjecting the dispersion to ultrasonic treatment at an output of 140 ± 10 W for 22 minutes. An external ultrasonic probe (750 W generator Synetude Lab 750) adjusted to supply 140 ± 10 W was used. An ice bath was used so that the suspension would not be heated above 45 °C during measurement.

[0104] The external ultrasonic probe was directly connected to the laser diffractometer so that D50 and D90 could be measured over time (one measurement every 13 seconds, 100 measurements in total for the analysis of particle defragmentation). For the inorganic material M of the present invention, it was observed that D50 and D90 decreased over time and reached a plateau.

[0105] By the method of the present invention, other inorganic materials M with various compositions can be obtained. See Examples 1 and 6.

[0106] Example 1: Preparation of Inorganic Material M According to the Present Invention The precursor is prepared using the process of the present invention. Solution S is prepared by mixing 387.2 g of distilled water, a solution of 95 g of La(NO3)3 (C = 472.5 g / L, density d = 1.7111), a solution of 69.8 g of ZrO(NO3)2 (C = 268.1 g / L, d = 1.415), and 4.03 g of Al(NO3)3 previously dissolved in 8 g of distilled water. Solution S is stirred at 400 rpm and supplied drop by drop over 1 hour into a tank-type reactor (volume 1 L) containing 429.5 g of distilled water and 63.4 g of concentrated ammonia (28.0 wt%). The amount of ammonia used corresponds to a 40% excess (molar ratio r = 1.40). A white precipitate is formed.

[0107] After addition, the mixture is removed from the reactor and transferred to a sealed pressure tank (autoclave), where it is heated at a heating rate of 2.5 °C / min (150 rpm) to 150 °C for 4 hours while stirring. Then, the mixture is allowed to cool to room temperature while stirring and removed from the autoclave.

[0108] An organic additive (lauric acid, 40 wt% based on the final expected weight of the inorganic material) is added to the precipitate while stirring (400 rpm). At the end of the addition, stirring is maintained for 30 minutes. Then, the mixture is filtered and washed with basic water (amount of basic water: 1 L; pH about 9).

[0109] Thereafter, the cake is calcined in air at 500 °C for 4 hours. The calcination temperature of 500 °C is reached at a heating rate of 4 °C / min. Then, the Al-doped precursor is ground in a mortar to obtain a homogeneous product.

[0110] To obtain 5 g of inorganic material M, 5.54 g of the Al-doped precursor is weighed (equivalent to 90.3% of the oxide). A solution of lithium nitrate is prepared (dissolving 3.26 g of LiNO3 in 2.0 g of water). This corresponds to a 10.0% Li excess. An aqueous solution of LiNO3 is impregnated into the Al-doped precursor by dropping the solution onto the stirred precursor with a spatula. A wet cake is obtained at the end of this step. After drying the cake in a preheated kettle at 120 °C for 2 hours, it is ground in a mortar. Then, the powder is calcined in a crucible with an alumina lid in air at 900 °C for 6 hours, reaching the calcination temperature at a heating rate of 5 °C / min. Then, the powder obtained after calcination is ground in a mortar. Thereafter, a second calcination of the powder is performed in a crucible with an alumina lid in air at 1000 °C for 6 hours using a heating rate of 5 °C / min and a cooling rate of 2 °C / min. The powder is ground in a mortar.

[0111] The relative composition of the cations in the inorganic material M obtained after impregnation and calcination is Li 6.44 Al 0.22 La3Zr 1.99 (determined by ICP).

[0112] Example 2: Preparation of Inorganic Material M According to the Present Invention In step (6), the same process as described in Example 1 was carried out except that only one calcination step at 800 °C for 6 hours was applied. After a heating rate of 5 °C / min, the temperature of 800 °C is reached.

[0113] Example 3: Preparation of Inorganic Material M According to the Present Invention In solution S, the same process as described in Example 1 was carried out except that Ga(NO3)3 was used instead of Al(NO3)3. The relative composition of the cations in the inorganic material M obtained after impregnation and calcination is Li 6.80 Al 0.05 Ga 0.19 La3Zr 1.94 (determined by ICP).

[0114] Example 4: Preparation of Inorganic Material M According to the Present Invention In solution S, the same process as described in Example 1 was carried out except that a mixture of Al(NO3)3 and Ga(NO3)3 was used. The relative composition of the cations in the inorganic material M obtained after impregnation and calcination is Li 6.65 Al 0.13 Ga 0.10 La3Zr 1.94 (determined by ICP).

[0115] Example 5: Preparation of Inorganic Material M According to the Present Invention The precursor is prepared using the process of the present invention. Solution S consists of 393.4 g of distilled water, 95.66 g of La(NO3)3 (C = 472.5 g / L, density d = 1.7111), 52.78 g of ZrO(NO3)2 (C = 268.1 g / L, d = 1.415), and 18.73 g of the formula C6H4NNbO 12It is prepared by mixing with ammonium niobium oxalate represented by []. Solution S is stirred at 400 rpm and supplied drop by drop over 1 hour into a tank reactor (volume 1 L) containing 428.4 g of distilled water and 64.4 g of concentrated ammonia (28.0% by weight). The amount of ammonia used corresponds to a 40% excess (molar ratio r = 1.40). A white precipitate is formed.

[0116] After addition, the mixture is heated at 98 °C for 4 hours in the reactor with stirring (400 tours / min). Then, the mixture is allowed to cool to room temperature overnight with stirring.

[0117] An organic additive (lauric acid, 40% by weight of the expected final oxide weight) is added to the precipitate with stirring (400 tours / min). At the end of the addition, stirring is continued for 30 minutes. Then, the mixture is filtered and washed with basic water (amount of basic water: 1 L; pH about 9).

[0118] Thereafter, the cake is calcined in air at 500 °C for 4 hours. The calcination temperature of 500 °C is reached at a heating rate of 4 °C / min. Then, the Nb-doped precursor is ground in a mortar to obtain a homogeneous product.

[0119] To obtain the inorganic material M of 5G, 5.58 g of the Nb-doped precursor is weighed (equivalent to 89.7% of the oxide). A solution of lithium nitrate is prepared (3.06 g of LiNO3 is dissolved in 2.9 g of water). This corresponds to 10.0% Li excess. By dropping the solution onto the stirred precursor with a spatula, the Nb-doped precursor is impregnated with an aqueous solution of LiNO3. A wet cake is obtained at the end of this step. After drying the cake at 110 °C for 2 hours in a preheated stove, it is pulverized in a mortar. Then, the powder is calcined in a crucible with an alumina lid at 900 °C for 6 hours in air, reaching the calcination temperature at a heating rate of 5 °C / min. Thereafter, the powder is pulverized in a mortar. Then, in a crucible with an alumina lid, using a heating rate of 5 °C / min and a cooling rate of 2 °C / min, the powder is subjected to a second calcination at 1000 °C in air for 6 hours. The powder is pulverized in a mortar. The relative composition of the cations in the inorganic material M obtained after impregnation and calcination is Li 7.00 Al 0.03 Nb 0.57 La3Zr 1.45 (determined by ICP).

[0120] Example 6: Preparation of the inorganic material M according to the invention The precursor was prepared using the process of the present invention. Solution S is prepared by mixing 395 g of distilled water, 94.24 g of La(NO3)3 (C = 472.5 g / L, density d = 1.7111), 69.26 g of ZrO(NO3)2 (C = 268.1 g / L, d = 1.415), and 4.39 g of Fe(NO3)3. Solution S is stirred at 400 rpm and fed drop by drop into a tank-type reactor (volume 1 L) containing 433.8 g of distilled water and 66.2 g of concentrated ammonia (28.0 wt%) over 1 hour. The amount of ammonia used corresponds to a 40% excess (molar ratio r = 1.40). A white precipitate is formed.

[0121] After addition, the mixture is withdrawn from the reactor and transferred into a sealed pressure tank (autoclave), where it is heated at a heating rate of 2.5 °C / min (150 rpm) to 150 °C for 4 hours while stirring. Next, the mixture is allowed to cool to room temperature while stirring and then withdrawn from the autoclave.

[0122] An organic additive (lauric acid, 40 wt% of the expected final oxide weight) is added to the precipitate while stirring (400 rpm). At the end of the addition, stirring is continued for 30 minutes. The mixture is then filtered and washed with basic water (amount of basic water: 1 L; pH about 9).

[0123] Thereafter, the cake is calcined in air at 500 °C for 4 hours. The calcination temperature of 500 °C is reached at a heating rate of 4 °C / min. Thereafter, the Fe-doped precursor is ground in a mortar to obtain a homogeneous product.

[0124] To obtain 5 g of the inorganic material M, 5.62 g of the Fe-doped precursor is weighed (corresponding to 89.0% of the oxide). A solution of lithium nitrate is prepared (2.96 g of LiN dissolved in 4.4 g of water). This corresponds to a 10.0% Li excess. The Fe-doped precursor is impregnated with an aqueous solution of LiN by dropping the solution onto the stirring precursor with a spatula. A wet cake is obtained at the end of this step. After drying the cake in a preheated oven at 120 °C for 2 hours, it is ground in a mortar. The powder is then calcined in a crucible with an alumina lid in air at 900 °C for 6 hours, reaching the calcination temperature at a heating rate of 5 °C / min. The powder is then ground in a mortar. Thereafter, a second calcination of the powder is performed in a crucible with an alumina lid in air at 1000 °C for 6 hours using a heating rate of 5 °C / min and a cooling rate of 2 °C / min. The powder is ground in a mortar.

[0125] The relative composition of the cations in the inorganic material M obtained after impregnation and calcination is Li 6.91 Al 0.05 Fe 0.21 La3Zr 1.97 (determined by ICP).

[0126] Comparative Example C1: Preparation of Inorganic Material by Conventional Solid Phase Technique The inorganic material was prepared by a conventional solid phase technique. For this purpose, 10.44 g of Li2CO3, 9.80 g of ZrO2, 19.40 g of La2O3, and 0.41 g of Al2O3 were mixed together for 2 hours using a 3D shaker equipped with ZrO2 - Y2O3 (diameter = 1 cm) balls. The powder / ball / air ratio is 1 / 3, 1 / 3, 1 / 3 by volume. 19.5 g of the obtained mixture was placed in an alumina crucible equipped with an alumina lid and calcined in air at 900 °C for 12 hours at a heating rate of 5 °C / min and a cooling rate of 2 °C / min. The calcined powder was mixed in a 3D shaker for 2 hours using the same balls at the same ratio as already disclosed. Then, the mixture was calcined in air at 1000 °C for 12 hours at a heating rate of 5 °C / min and a cooling rate of 2 °C / min, and then mixed again in a 3D shaker with the same balls for 2 hours. Finally, a final calcination step is performed at 1100 °C for 12 hours at a heating rate of 5 °C / min and a cooling rate of 2 °C / min before grinding to obtain the final product.

[0127] Comparative Example C2: Preparation of Inorganic Material without Lauric Acid The recipe used corresponded to the recipe described in Example 1, but did not contain lauric acid.

[0128] [Table 1]

Claims

1. An inorganic material M comprising, or consisting essentially of, a garnet oxide or garnet-type oxide containing, as constituent elements, the elements Li, La, Zr and at least one element A selected from the group consisting of Al, Ga, Nb, Fe, W, Ta, or a mixture thereof, wherein the garnet oxide or garnet-type oxide has the formula (I): [Li ｘ１ La ３ Zr ｚ A ｗ O １２ (I) (wherein, - x1, z, and w are positive real numbers; - 1.20 < z ≤ 2.10; - 0 < w ≤ 0.80; - x1 is derived from the electrical neutrality of the oxide); represented by - the following formula: R50(%) = (D50 - D ＵＳ 50) / D50 × 100 The R50 defined by is greater than 70%, and D50 and D ＵＳ 50 is the median diameter of the volume distribution of the diameter of the dispersion of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained by a laser diffractometer, and D ＵＳ 50 is measured after performing ultrasonic treatment consisting of inserting an ultrasonic probe into a dispersion of 100 mg of the inorganic material M in 160 mL of NMP and subjecting the dispersion to ultrasonic treatment at an output of 140 ± 10 W for 22 minutes, and / or - the following formula: R90(%) = (D90 - D ＵＳ 90) / D90 × 100 R90 defined by is more than 70%, and D90 and D ＵＳ 90 corresponds to the diameter of particles having a diameter less than D90 for 90% of the particles, which is determined from the volume distribution of the diameter of the dispersion of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained by a laser diffractometer, D ＵＳ 90 is measured after performing ultrasonic treatment consisting of inserting an ultrasonic probe into a dispersion of 100 mg of the inorganic material M in 160 mL of NMP and subjecting the dispersion to ultrasonic treatment at an output of 140 ± 10 W for 22 minutes, Inorganic material M.

2. An inorganic material M comprising, or consisting essentially of, a garnet oxide or garnet-type oxide containing, as constituent elements, the elements Li, La, Zr and at least one element A selected from the group consisting of Al, Ga, Nb, Fe, W, Ta, or a mixture thereof, wherein the garnet oxide or garnet-type oxide has the formula (I): [Li ｘ１ La ３ Zr ｚ A ｗ O １２ (I) (wherein, - x1, z, and w are positive real numbers; - 1.20 < z ≤ 2.10; - 0 < w ≤ 0.80; - x1 is derived from the electrical neutrality of the oxide); represented by - the following formula: R50(%) = (D50 - D ＵＳ 50) / D50 × 100 R50 defined by is more than 70%, and D50 and D ＵＳ 50 is the median diameter of the volume distribution of the diameter of the dispersion of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained by a laser diffractometer, and D ＵＳ 50 is the inorganic material M measured after performing ultrasonic treatment consisting of inserting an ultrasonic probe into a dispersion of 100 mg of the inorganic material M in 160 mL of NMP and subjecting the dispersion to ultrasonic treatment at an output of 140 ± 10 W for 22 minutes.

3. The relative composition of the cations in the inorganic material M corresponds to the following formula: Li ｘ La ３ Zr ｚ A ｗ (II) (wherein, - w, x, and z are positive real numbers; - 1.20 < z ≤ 2.10; - 0 < w ≤ 0.80; - 4.00 ≤ x ≤ 10.5), the inorganic material M according to claim 1 or 2.

4. The relative composition of the cations in the inorganic material M corresponds to the following formula: Li ｘ La ３ Zr ｚ Al ｗ１ A2 ｗ２ (IIa) (wherein, - A1 is selected from the group consisting of Al, Ga, Fe, or a combination thereof; - A2 is selected from the group consisting of Nb, Ta, or a combination thereof; - w1, w2, x, and z are positive real numbers; - 1.20 < z ≤ 2.10; - 0.10 < w2 ≤ 0.80; - w1 and w2 are such that w = w1 + w2 and w ≤ 0.80; - 5.60 ≤ x ≤ 10.35), the inorganic material M according to claim 1 or 2.

5. The relative composition of the cations in the inorganic material M corresponds to the following formula: Li ｘ La ３ Zr ｚ Al ｗ１ A2 ｗ２ (IIb) (wherein, - A1 is selected from the group consisting of Al, Ga, Fe, or a combination thereof: - A2 is W; - w1, w2, x, and z are positive real numbers; - 1.20 < z ≤ 2.10; - 0 < w1 ≤ 0.20; - 0.10 < w2 ≤ 0.80; - w1 and w2 are such that w = w1 + w2 and w ≤ 0.80; - The inorganic material M according to claim 1 or 2, corresponding to 4.80 ≤ x ≤ 10.20).

6. The inorganic material M according to any one of claims 1 to 5, wherein 1.90 ≤ z ≤ 2.

10.

7. The inorganic material M according to any one of claims 1 to 6, wherein w ≥ 0.

05.

8. The inorganic material M according to any one of claims 1 to 7, wherein the inorganic material M and / or the oxide exhibits a cubic crystal structure.

9. The inorganic material M according to claim 8, wherein the cubic crystal structure is represented by the Ia-3d space group or the I-43d space group.

10. The crystal structure of the oxide is composed of an 8-coordinated LaO ８ dodecahedron and a 6-coordinated ZrO ６ octahedron framework, and the inorganic material M according to any one of claims 1 to 9.

11. The crystal structure of the oxide is LiO ４ tetrahedra and LiO ６ octahedra, and the inorganic material M according to any one of claims 1 to 10.

12. The inorganic material M according to claim 10 or 11, wherein the outside of the crystal structure contains lithium cations.

13. The inorganic material M according to any one of claims 1 to 12, wherein Zr in the oxide is partially replaced by Hf.

14. The inorganic material M according to claim 13, wherein the molar ratio Hf / Zr is 1 / 100 to 5 / 100.

15. The inorganic material M according to any one of claims 1 to 14, wherein the inorganic material M is formed of particles aggregated from primary particles showing a d50 of 0.5 μm to 7.0 μm.

16. The inorganic material M according to any one of claims 1 to 15, wherein the particles of the inorganic material M show a D50 of 10.0 to 50.0 μm.

17. The inorganic material M according to any one of claims 1 to 16, wherein the particles of the inorganic material M show a D90 of less than 150.0 μm.

18. The inorganic material M according to any one of claims 1 to 17, wherein the particles of the inorganic material M show a D90 of 20.0 to 150.0 μm.

19. The inorganic material M according to any one of claims 1 to 18, wherein the particles of the inorganic material M show a D10 of 0.5 μm or more, and D10 corresponds to the diameter of particles having a diameter less than D10 for 10% of the particles, which is determined from the volume distribution of the diameter of the dispersion of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained by a laser diffractometer.

20. The particles of the inorganic material M exhibit a D10 of 0.5 to 15.0 μm, where D10 corresponds to the diameter of the particles having a diameter less than D10 for 10% of the particles, which is determined from the volume distribution of the diameter of the dispersion of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained by a laser diffractometer. The inorganic material M according to any one of claims 1 to 19.

21. Exhibiting an intensity ratio (b / a) of less than 0.05, where a and b are the intensities of the peaks appearing in the XRD diagram at 2θ of 16.0° to 17.0° and 2θ of 28.5° to 28.7°, respectively. The inorganic material M according to any one of claims 1 to 20.

22. (1) A step of contacting an aqueous solution S containing (i) a salt of zirconium, (ii) a salt of lanthanum, and (iii) a precursor of a salt of element A or an oxide of element A with an aqueous solution of a basic compound, as a result, obtaining a precipitate suspended in the reaction medium; (2) A step of stirring the reaction medium obtained at the end of step (1) for at least 30 minutes; (3) A step of contacting the precipitate obtained at the end of step (2) with an additive selected from the group consisting of an anionic surfactant; a nonionic surfactant; polyethylene glycol; carboxylic acids and their salts; and a carboxymethylated fatty alcohol ethoxylate type surfactant; (4) A step of calcining the precipitate recovered at the end of the previous step in air at a temperature of at least 400 °C to obtain a calcined product; (5) A step of contacting the calcined product obtained at the end of step (4) with a salt of lithium to obtain a product containing lithium; (6) A step of calcining the product obtained at the end of step (5) in air at a temperature of 700 °C to 1100 °C; A method for producing an inorganic material M, comprising: The inorganic material M contains, as constituent elements, a garnet oxide or a garnet-type oxide containing at least one element A selected from the group consisting of element Li, La, Zr, and at least one element selected from the group consisting of Al, Ga, Nb, Fe, W, Ta, or a mixture thereof, or consists essentially of this. The inorganic material M exhibits an R50 of more than 70%, where R50 is given by the following formula: R50 (%) = (D50 - D US 50) / D50 × 100 defined by, where D50 and DUS50 are the median diameters of the volume distribution of the diameters of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained by a laser diffractometer, and DUS50 is obtained by inserting an ultrasonic probe into a dispersion of 100 mg of the inorganic material M in 160 mL of NMP and subjecting the dispersion to ultrasonic treatment consisting of ultrasonic treatment at an output of 140 ± 10 W for 22 minutes; and / or the inorganic material M exhibits an R90 of more than 70%, where R90 is given by the following formula: R90 (%) = (D90 - DUS90) / D90 × 100 defined by, where D90 and DUS90 correspond to the diameters of the particles having a diameter less than D90 for 90% of the particles, which is determined from the volume distribution of the diameters of the particles of the inorganic material M in N-methyl-2-pyrrolidone (NMP) obtained by a laser diffractometer, and DUS90 is measured after performing ultrasonic treatment consisting of inserting an ultrasonic probe into a dispersion of 100 mg of the inorganic material M in 160 mL of NMP and subjecting the dispersion to ultrasonic treatment at an output of 140 ± 10 W for 22 minutes, method.

23. The method according to claim 22, wherein the salt of zirconium is selected from the group consisting of zirconium nitrate and zirconium chloride.

24. The method according to claim 22 or 23, wherein in step (2), the reaction medium is stirred for at least 30 minutes and the temperature of the reaction medium is 50°C to 200°C.

25. The method according to any one of claims 22 to 24, wherein the additive is a carboxylic acid or a salt thereof.

26. The method according to any one of claims 22 to 25, wherein the calcination temperature in step (4) is 400°C to 800°C.

27. The contacting in step (5) consists of impregnating the calcined product obtained at the end of step (4) with an aqueous solution of a lithium salt, or mixing together the calcined product obtained at the end of step (4) and the lithium salt in powder form, the method according to any one of claims 22 to 26.

28. The method according to any one of claims 22 to 27, wherein in step (6), the product obtained at the end of step (5) is first calcined in air at a temperature of 700°C to 900°C and then calcined in air at a temperature of 900°C to 1100°C.

29. (i) the inorganic material M according to claims 1 to 21, and (ii) at least one electroactive compound (EAC); (iii) optionally, at least one lithium ion conducting material (LiCM) other than the inorganic material M; (iv) optionally, at least one electrically conductive material (ECM); (v) optionally, a lithium salt (LIS); (vi) optionally, at least one polymeric binder material (P); A composition (C) comprising:

30. - A metal substrate; - At least one layer L directly adhered onto the metal substrate and produced from the composition (C) according to claim 29; An electrode (E) comprising:

31. - The inorganic material M according to claims 1 to 21; - Optionally, at least one polymeric binder material (P); - Optionally, at least one metal salt; - Optionally, at least one plasticizer; A separator (SP) comprising:

32. Use of the inorganic material M according to any one of claims 1 to 21 for the manufacture of a lithium ion battery.

33. A lithium ion battery comprising the inorganic material M according to any one of claims 1 to 21.

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