Doped lithiated solid electrolyte material

Abstract

The invention provides a method for preparing doped lithium lanthanum zirconium oxide. The method comprises: contacting an aqueous solution comprising lithium ions with a solid comprising lanthanum, zirconium, and one or more dopant species for incorporation into the doped lithium lanthanum zirconium oxide; forming a precipitate comprising lithium; and calcining the precipitate comprising lithium to form the doped lithium lanthanum zirconium oxide. Related methods, products, starting materials, and intermediates are also provided.

Description

Technical Field

[0001] This application relates to doped lithium-ion solid electrolyte materials, specifically, but not limited to, doped lithium lanthanum zirconium oxide.

[0002] This invention relates to doped lithium-ion solid electrolyte materials. More specifically, but not limited to, this invention relates to methods for preparing doped lithium-ion solid electrolyte materials. The invention also relates to doped lithium-ion solid electrolyte materials, compositions for forming doped lithium-ion solid electrolyte materials, and two-part reaction mixture compositions for forming doped lithium-ion solid electrolyte materials. Background Technology

[0003] Doped lithiated solid electrolyte materials are typically prepared via solid-state synthesis. This usually requires excessively long periods of high-temperature heating. Such methods are energy-intensive and difficult to scale up for large-scale production. Furthermore, in some cases, extensive post-processing of the prepared material is required. For example, the lithiation process may involve ball milling, which is energy-intensive and unreliable. The lithiation process may also involve spray drying or freeze-drying, which can be energy-intensive due to the need to remove almost all solvent.

[0004] The present invention aims to alleviate the above-mentioned problems. Alternatively or additionally, the present invention aims to provide an improved method for preparing doped lithium-ion solid electrolyte materials, specifically but not limited to doped lithium lanthanum zirconium oxide (sometimes referred to as LLZO in this application). Invention Overview According to a first aspect of the present invention, a method for preparing a doped lithium-ion solid electrolyte material (preferably a doped lithium lanthanum zirconium oxide) is provided, the method comprising: The lithium material is brought into contact with a solid containing one or more substances for incorporation into a solid electrolyte material, wherein the one or more substances for incorporation into the solid electrolyte material contain one or more dopants (preferably, a solution containing lithium ions—especially an aqueous or partially aqueous solution containing lithium ions—is brought into contact with a solid containing lanthanum, zirconium, and one or more dopant substances for incorporation into the doped lithium lanthanum zirconium oxide). Formation of lithium-containing precipitates; and Heating (preferably calcining) a lithium-containing precipitate to form a doped lithium-ionized solid electrolyte material (preferably a doped lithium lanthanum zirconium oxide).

[0006] For the avoidance of doubt, "lithiated solid electrolyte material" refers to a solid electrolyte material containing lithium. Preferably, the lithiated solid electrolyte material is a doped lithium lanthanum zirconium oxide.

[0007] Therefore, preferably, the method according to the first aspect of the present invention is a method for preparing doped lithium lanthanum zirconium oxide, the method comprising: A solution containing lithium ions (preferably aqueous, or at least partially aqueous) is brought into contact with a solid, the solid comprising lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide; Formation of lithium-containing precipitates; and Heating (especially calcining) lithium-containing precipitates to form doped lithium lanthanum zirconium oxide.

[0008] To avoid ambiguity, contacting a lithium material with a solid containing one or more substances for incorporation into a solid electrolyte material (especially contacting a lithium-ion-containing solution—preferably an aqueous or at least partially aqueous solution containing lithium ions—with a solid containing lanthanum, zirconium, and one or more dopant substances for incorporation into the doped lithium lanthanum zirconium oxide) can result in the formation of a lithium-containing precipitate. The formation of the lithium-containing precipitate does not necessarily need to be a separate step from contacting the lithium material with the solid containing one or more substances for incorporation into the solid electrolyte material.

[0009] The applicant has unexpectedly discovered that doped lithium-ionized solid electrolyte materials (especially doped lithium lanthanum zirconium oxide) can be prepared using mild aqueous precipitation chemistry methods. Examples of such methods generally do not generate hazardous waste and typically employ relatively stable precursors. For example, contacting a lithium material with a solid containing one or more substances for incorporation into the solid electrolyte material (in particular, contacting a solution containing lithium ions—preferably an aqueous or at least partially aqueous solution containing lithium ions—with a solid containing lanthanum, zirconium, and one or more dopant substances for incorporation into the doped lithium lanthanum zirconium oxide) can optionally be carried out at temperatures not exceeding 60°C, optionally not exceeding 50°C, optionally not exceeding 40°C, and optionally not exceeding 30°C. Contacting a lithium material with a solid containing one or more substances for incorporating a solid electrolyte material (especially contacting a lithium-ion-containing solution—preferably an aqueous or at least partially aqueous solution containing lithium ions—with a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide) can be performed at temperatures of at least 0°C, optionally at least 5°C, optionally at least 10°C, and optionally at least 15°C. Contacting a lithium material with a solid containing one or more substances for incorporating a solid electrolyte material (contacting a lithium-ion-containing solution—preferably an aqueous or at least partially aqueous solution containing lithium ions—with a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide) can be performed optionally at temperatures of 5-60°C, optionally 10-40°C, and optionally 15-25°C. The lithium material is brought into contact with a solid containing one or more substances for incorporating the solid electrolyte material (in particular, a solution containing lithium ions—preferably an aqueous or at least partially aqueous solution containing lithium ions—is brought into contact with a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide), optionally at ambient temperature.

[0010] The lithium substance can be in the form of lithium ions, particularly in the form of a solution containing lithium ions; preferably, an aqueous solution or at least a partially aqueous solution containing lithium ions. It should be understood that the liquid component of the aqueous solution is water (or substantially water, optionally with small amounts of other liquid components such as impurities). It should also be understood that the liquid component of the partially aqueous solution contains water and may contain other polar or nonpolar (especially polar) liquids, such as one or more alcohols (e.g., ethanol) or other polar liquids (e.g., acetone). Preferably, the lithium ions are in the aqueous solution.

[0011] A solid containing one or more substances for incorporating a solid electrolyte material (preferably a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide) may contain a precipitate containing one or more substances for incorporating a solid electrolyte material (preferably lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide).

[0012] The method of the first aspect of the present invention is optionally carried out in an aqueous liquid.

[0013] The method optionally includes contacting a solid containing one or more substances for incorporating a solid electrolyte material (preferably a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide) with lithium ions. The lithium ions can be provided by forming a solution (preferably an aqueous solution) containing lithium ions (e.g., by dissolving a lithium salt), and contacting the solid (optionally a precipitate) with the solution. Alternatively or additionally, the solid will be present in a liquid (such as water or an aqueous mixture), and the method may include dissolving a lithium salt in the liquid to provide lithium ions. The lithium salt may include any suitable lithium salt, such as lithium hydroxide, lithium nitrate, lithium halide, or lithium acetate.

[0014] The method of the present invention is a method for preparing doped lithium-ion solid electrolyte materials (preferably doped lithium lanthanum zirconium oxide). Such materials may comprise a lattice, optionally a crystalline lattice, wherein certain substances occupy lattice sites and certain substances occupy sites between lattice sites (sites between lattice sites are often referred to as "interstitial sites"). One or more dopants may optically occupy sites between lattice sites and / or occupy lattice sites. Optionally, one or more substances used to incorporate into the solid electrolyte material (preferably doped lithium lanthanum zirconium oxide) may contain substances for forming the lattice structure and thus optionally occupy lattice sites. For example, if the doped lithium-ion solid electrolyte material includes doped lithium lanthanum zirconium oxide, the dopant may be any suitable element other than lithium, lanthanum, zirconium, and oxygen. For example, the dopant may be any metal or half-metal (e.g., boron or tantalum) other than lithium, lanthanum, and zirconium. For example, the dopant may contain halogens. Optionally, some oxygen may be replaced by halogens.

[0015] This method may include forming a solid (optionally a precipitate) comprising one or more substances for incorporating a solid electrolyte material (preferably forming a solid comprising lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide). Forming a solid comprising one or more substances for incorporating a solid electrolyte material may include mixing at least two compositions, at least one of which comprises one or more substances for incorporating the solid electrolyte material (preferably including one or more dopant substances). Optionally, at least one of the compositions is in the form of a solution (preferably an aqueous solution). Optionally, at least one of the compositions is in the form of a suspension (preferably an aqueous suspension). Optionally, two of the at least two compositions are in the form of solutions. (Therefore, a preferred step in forming a solid comprising lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide may include mixing at least two solutions, wherein at least one solution comprises one or more dopant substances for incorporating the solid electrolyte material). Optionally, at least one of the compositions comprises a base, such as a hydroxide, carbonate, or bicarbonate. Optionally, at least one of the compositions comprises one or more substances for forming the lattice structure of the doped lithium-ionized solid electrolyte material, and optionally comprises one or more dopant substances. Optionally, at least one of the compositions comprises one or more substances for forming the lattice structure of the doped lithium-ion solid electrolyte material, but without a dopant, and another composition comprises one or more dopants. Optionally, at least one of the compositions comprises one or more substances for forming the lattice structure of the doped lithium-ion solid electrolyte material, and one or more dopants, and another composition comprises one or more dopants, and optionally a base. Optionally, at least one of the compositions comprises one or more substances for forming the lattice structure of the doped lithium-ion solid electrolyte material, and one or more dopants, and another composition comprises a base but without a dopant. Optionally, one of the compositions may be acidic.

[0016] For example, the first composition is optionally in the form of a solution and may contain one or more of the following: Zr, La, and optionally one or more dopants. The first composition may optionally be acidic. The second composition is optionally in the form of a solution but also optionally in the form of a suspension and may contain one or more of the following: a base, one or more dopants, and one or more of Zr and La. Such dopants may optionally be provided as polyoxometalates. It has been shown that providing two such compositions that can be mixed to form a solid (optionally a precipitate) is an efficient way to prepare a solid (in the form of a precipitate) from which doped lithium lanthanum zirconium oxide can be prepared.

[0017] Optionally, the first composition is optionally in the form of a solution and may contain one or more of the following: Zr, La, and optionally one or more dopants. The first composition may optionally be acidic. The second composition is optionally in the form of a solution but also optionally in the form of a suspension and may contain one or more of the following: a base and one or more dopants, but excluding one or more of Zr and La. It has been shown that providing two such compositions that can be mixed to form a precipitate is an efficient way to prepare a solid (optionally in the form of a precipitate) from which doped lithium lanthanum zirconium oxide can be prepared.

[0018] Optionally, the first composition is optionally in the form of a solution and may contain one or more of the following: Zr, La, and optionally one or more dopants. The first composition may optionally be acidic. The second composition is optionally in the form of a solution but also optionally in the form of a suspension, and may contain a base but does not contain one or more dopants, nor one or more of Zr and La. It has been shown that providing two such compositions that can be mixed to form a solid (optionally in the form of a precipitate) is an efficient way to prepare the following precipitate from which doped lithium lanthanum zirconium oxide can be prepared.

[0019] A solid comprising one or more substances for incorporation into a solid electrolyte material (preferably, a solid comprising lanthanum, zirconium, and one or more dopant substances for incorporation into said doped lithium lanthanum zirconium oxide) is formed, optionally at a pH of at least about 3.5, optionally at least about 4.0, optionally at least about 4.5, optionally at least about 5.0. The formation may optionally be carried out at a pH not greater than about 8.0, optionally not greater than about 7.5, optionally not greater than about 7.0, optionally not greater than about 6.5, optionally not greater than about 6.0, optionally not greater than about 5.5, optionally not greater than about 5.0.

[0020] A solid containing one or more substances for incorporating a solid electrolyte material (preferably a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide) may contain any substances other than lithium necessary for forming the doped lithiated solid electrolyte (preferably doped lithium lanthanum zirconium oxide). For example, if the doped lithiated solid electrolyte is doped LLZO, the solid containing one or more substances for incorporating the solid electrolyte material may contain lanthanum, zirconium, and any dopant (but not lithium).

[0021] The lithium-containing precipitate may optionally contain those substances necessary for forming the doped lithium-ion solid electrolyte (preferably doped lithium lanthanum zirconium oxide). For example, if the doped lithium-ion solid electrolyte is doped LLZO, the solid containing one or more substances for incorporating the solid electrolyte material may contain lithium, lanthanum, zirconium, and any dopant.

[0022] Forming a lithium-containing precipitate may include providing an anion source capable of forming an insoluble salt with lithium. For the avoidance of doubt, "providing" does not mean that the anion source capable of forming an insoluble salt with lithium is added in a separate step. For example, a composition comprising zirconium, lanthanum, and one or more dopant materials for forming a doped lithium lanthanum zirconium oxide may also include an anion source capable of forming an insoluble salt with lithium.

[0023] To avoid ambiguity, more than one dopant may be provided.

[0024] Preferably, the step of forming a lithium-containing precipitate is or includes: after the contact step, providing an anion source that forms an insoluble salt with lithium, thereby forming a lithium-containing precipitate. It is not desirable to be theoretically limited, but it is considered that providing the anion source after the contact step, rather than before, the contact step, can be an effective way to minimize the amount of lithium ions remaining in the solution, for example, by reducing the total amount of liquid (especially water) present as a carrier of the necessary component for product formation, thereby reducing the amount of liquid (especially water) available for dissolving lithium ions. This can lead to higher yields of doped lithium-ionized solid electrolyte materials, especially higher yields of doped lithium lanthanum zirconium oxide. Preferably, the anion source is or includes a carbonate anion source. Carbonate anions can provide a particularly effective way to promote the precipitation of lithium ions from the solution (specifically from an aqueous solution). The carbonate anion source can be or includes carbon dioxide. Using carbon dioxide instead of carbonates (e.g., ammonium carbonate) can reduce or eliminate undesirable byproducts (e.g., ammonia); the resulting lithium carbonate can also be reused without special purification.

[0025] Formation of a lithium-containing precipitate may optionally include: (i) contacting a lithium material (optionally lithium ions) with a composition comprising a solid containing one or more substances for incorporating a solid electrolyte material, followed by providing an anion source capable of forming an insoluble salt with lithium; (ii) contacting an anion source capable of forming an insoluble salt with lithium with a composition comprising a solid containing one or more substances for incorporating a solid electrolyte material, followed by providing a lithium material (optionally lithium ions); or (iii) simultaneously contacting (a) the lithium material (optionally lithium ions) and (b) the anion source capable of forming an insoluble salt with lithium with (c) a composition comprising a solid containing one or more substances for incorporating a solid electrolyte material, or (d) contacting a composition comprising a solid containing one or more substances for incorporating a solid electrolyte material with an anion source capable of forming an insoluble salt with lithium, and subsequently providing lithium ions. In some cases, option (i) is preferred because it can result in a higher yield of the desired product. Lithium ions can be provided by dissolving a soluble lithium salt in a liquid carrier liquid such as the salt. Alternatively or additionally, lithium ions can be provided by providing a solution of lithium ions and contacting the solution with the solid. When the doped lithium-ion solid electrolyte material is or contains doped lithium lanthanum zirconium oxide, forming a lithium-containing precipitate may include: (i) contacting a lithium-ion-containing (preferably aqueous or at least partially aqueous) solution with a solid (optionally a precipitate) containing lanthanum, zirconium, and one or more dopants for incorporating the doped lithium lanthanum zirconium oxide, followed by providing an anion source (especially a carbonate ion source) capable of forming an insoluble salt with lithium; (ii) contacting a solid (optionally a precipitate) containing lanthanum, zirconium, and one or more dopants for incorporating the doped lithium lanthanum zirconium oxide with an anion source (especially a carbonate ion source) capable of forming an insoluble salt with lithium, followed by providing a lithium-ion-containing (preferably aqueous or at least partially aqueous) solution; or (iii) simultaneously contacting a lithium-ion-containing (preferably aqueous or at least partially aqueous) solution and an anion source (especially a carbonate ion source) capable of forming an insoluble salt with lithium with a solid (optionally a precipitate) containing lanthanum, zirconium, and one or more dopants for incorporating the doped lithium lanthanum zirconium oxide. In some cases, option (i) is preferred because it can result in a larger yield of doped lithium lanthanum zirconium oxide.

[0026] An insoluble salt is one that is selectively insoluble in an aqueous solution, and its insolubility is sufficient to cause it to precipitate from the solution.

[0027] As described in this application, anion sources that can form insoluble salts with lithium may include carbonate anion sources. Lithium carbonate is slightly soluble in many liquids, such as aqueous liquids. Carbonate anion sources may include one or more of the following: carbonate ions, bicarbonate ions, and carbon dioxide. Carbon dioxide may be particularly effective because the solution from which lithium-containing precipitates are removed is a lithium carbonate solution, which can be reused without further purification. This reduces lithium loss.

[0028] Heating a lithium-containing precipitate to form a doped solid electrolyte material (preferably doped lithium lanthanum zirconium oxide) may optionally include calcining the lithium-containing precipitate. In this case, calcination includes heating to achieve a phase transition. Heating a lithium-containing precipitate to form a doped solid electrolyte material (preferably doped lithium lanthanum zirconium oxide) may optionally include heating the lithium-containing precipitate to the following temperatures: at least 500 °C, optionally at least 600 °C, optionally at least 700 °C, optionally at least 800 °C, optionally at least 900 °C, optionally at least 1000 °C. Heating a lithium-containing precipitate to form a doped solid electrolyte material (preferably doped lithium lanthanum zirconium oxide) may optionally include heating the lithium-containing precipitate to the following temperatures: not greater than 1500 °C, optionally not greater than 1400 °C, optionally not greater than 1300 °C, optionally not greater than 1200 °C, optionally not greater than 1100 °C, optionally not greater than 1000 °C.

[0029] The method may include separating lithium-containing precipitates from environmental liquids (such as aqueous liquids), for example, by using filtration.

[0030] The method may include drying a lithium-containing precipitate, optionally after separating the lithium-containing precipitate from an ambient liquid. Drying the lithium-containing precipitate may include heating the lithium-containing precipitate, optionally to a temperature not exceeding 200 °C, optionally not exceeding 180 °C, optionally not exceeding 160 °C, optionally not exceeding 140 °C, optionally not exceeding 120 °C, optionally not exceeding 100 °C. Drying the lithium-containing precipitate may also include subjecting the lithium-containing precipitate to reduced pressure.

[0031] In summary, the method of the first aspect of the present invention may be or include a method for preparing doped lithium lanthanum zirconium oxide, said method comprising the following steps in sequence: (a) Contacting a first composition with a second composition (optionally at a pH of at least about 3.5), the first composition being in the form of an aqueous solution and containing Zr, La and optionally one or more dopants, and the second composition being in the form of an aqueous solution or suspension and containing one or more dopants, thereby forming a first precipitate containing Zr, La and one or more dopants. (b) Contacting the first precipitate with a lithium-ion-containing solution (preferably aqueous or at least partially aqueous); (c) Subsequently, an anion source (optionally carbonate) is added to the mixture obtained in step (b), which forms an insoluble salt with lithium, thereby forming a second precipitate containing lithium; and (d) Heating (optionally calcining) the second precipitate to form doped lithium lanthanum zirconium oxide.

[0032] Optionally, at least one substance for incorporating the doped lithium-ion solid electrolyte material (preferably doped lithium lanthanum zirconium oxide), and optionally at least one dopant, may be provided as a polyoxometalate. Optionally, when the doped lithium-ion solid electrolyte material is or contains doped lithium lanthanum zirconium oxide, at least one substance for incorporating the doped lithium lanthanum zirconium oxide is provided as a polyoxometalate, and optionally at least one dopant substance is provided as a polyoxometalate. Optionally, at least one dopant is not provided by a polyoxometalate. For example, if the dopant in the lithium-ion solid electrolyte material to be doped (preferably doped lithium lanthanum zirconium oxide) is a metal, the dopant may optionally be provided as a polyoxometalate. For example, a solid (optionally a precipitate) containing one or more substances for incorporating the solid electrolyte material (preferably a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide) may contain a polyoxometalate. Alternatively, the method may include forming a solid from a solution containing a polyoxometalate containing one or more substances for incorporating a solid electrolyte material (preferably a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating doped lithium lanthanum zirconium oxide). Polyoxometalates are polyatomic ions, typically but not always anions, comprising three or more metal-oxygen anions linked together by shared oxygen atoms to form a closed 3D framework structure. The metal is typically a transition metal. Such polyoxometalates may include one or more of the following: niobium, molybdenum, tungsten, tellurium, tantalum, and aluminum. Each polyoxometalate ion may contain at least three, optionally at least four, optionally at least five, optionally at least six, and optionally at least seven metallic substances. Each polyoxometalate ion may contain no more than 300 metals, optionally no more than 250, optionally no more than 200, optionally no more than 150, optionally no more than 100, optionally no more than 80, optionally no more than 60, optionally no more than 50, optionally no more than 40, optionally no more than 30, optionally no more than 20, optionally no more than 15, optionally no more than 14, optionally no more than 13, optionally no more than 12, optionally no more than 11, optionally no more than 10, optionally no more than 9, optionally no more than 8, and optionally no more than 7 metals. For the avoidance of ambiguity, this does not refer to the number of different metals in the ion, but rather to the number of metal atoms / ions in the polyoxometalate ion.

[0033] For example, polyoxometalates can have Keggin, Lindqvist, or Anderson-Evans structures.

[0034] Optionally, the polyoxometalate may include one or more of the following: [Nb6O 19 ]8- [Mo7O] 24 ] 6- ,[TeNb5O 19 ] 7- 、[ [TeW6O 24 ] 6- 、[Nb 6-x W x O 19 ] (8-x)- Nb3W3O 19 ] 5- [Nb3Ta3O] 19 ] -8 [W] 12 O 40 ] 8- [W] 12 O 42 ] 12- and [Al 13 O4(OH) 24 ] 7+ , where x is an integer from 1 to 5.

[0035] A variety of substances can be provided for incorporation into doped lithium-ion solid electrolyte materials (preferably doped lithium lanthanum zirconium oxide). One, more, or all of these substances (optionally including any dopant) can be provided in the solid in contact with a lithium substance (such as lithium ions). Alternatively, one or more of these substances can be provided separately from the solid, for example, in a solution or suspension to be in contact with the solid.

[0036] One or more substances used for incorporating doped lithium-ion solid electrolyte materials (preferably doped lithium lanthanum zirconium oxide) may include one or more of the following: lanthanum, zirconium, aluminum, germanium, and titanium. One or more of these substances may be present in the solid in contact with the lithium material, optionally lithium ions, particularly a solution containing lithium ions (preferably aqueous or at least partially aqueous). One or more of these substances may be provided separately from the solid, for example, in the solution or suspension to be in contact with the solid.

[0037] One or more substances used for incorporating the doped lithium-ion solid electrolyte material may comprise lanthanum and zirconium. One or more of these substances may be present in the solid in contact with the lithium substance, optionally lithium ions, particularly a solution containing lithium ions (preferably aqueous or at least partially aqueous). One or more of these substances may be provided separately from the solid, for example, in a solution or suspension to be in contact with the solid.

[0038] One or more substances used for incorporating the doped lithium-ion solid electrolyte material (preferably doped lithium lanthanum zirconium oxide) may contain aluminum and germanium. One or more of these substances may be present in the solid in contact with the lithium material, optionally lithium ions (preferably an aqueous solution or at least a partially aqueous solution containing lithium ions). One or more of these substances may be provided separately from the solid, for example, in a solution or suspension to be in contact with the solid.

[0039] One or more substances used for incorporating doped lithium-ion solid electrolyte materials (preferably doped lithium lanthanum zirconium oxide) may contain lanthanum and titanium. One or more of these substances may be present in the solid in contact with the lithium material, optionally lithium ions (preferably an aqueous solution or at least a partially aqueous solution containing lithium ions). One or more of these substances may be provided separately from the solid, for example, in a solution or suspension to be in contact with the solid.

[0040] The doped lithium-ion solid electrolyte material (preferably doped lithium lanthanum zirconium oxide) optionally comprises one or more of the following: lanthanum, zirconium, aluminum, germanium, and titanium. For example, the doped lithium-ion solid electrolyte material may comprise lithium, aluminum, and germanium, optionally in combination with phosphates. The doped lithium-ion solid electrolyte material may comprise lithium aluminum germanium phosphate. The doped lithium-ion solid electrolyte material may comprise Li... A Al B Ge C (PO4) D Where A = 1.0-2.0, B = 0.01-1.0, C = 1.0-2.0, and D = 2.0-4.0, optionally D = 3. The doped lithium-ion solid electrolyte material may contain lithium, aluminum, and titanium, optionally in combination with phosphates. The doped lithium-ion solid electrolyte material may contain lithium aluminum titanium phosphate. The doped lithium-ion solid electrolyte material may contain Li... A Al B Ti C (PO4) D Where A = 1.0-2.0, B = 0.01-1.0, C = 1.0-2.0, and D = 2.0-4.0, optionally D = 3. The doped lithium-ion solid electrolyte material may contain lithium lanthanum titanate. The doped lithium-ion solid electrolyte material may contain Li A La B Ti C O D Where A = 0.01-1.0, B = 0.01-1.0, C = 0.5-1.5, and D = 2.0-4.0, and D can be arbitrarily set to 3.

[0041] For example, the lithium-ion solid electrolyte material optionally comprises lithium, lanthanum, and zirconium. Preferably, the lithium-ion solid electrolyte material is or comprises doped lithium lanthanum zirconium oxide. The doped lithium-ion solid electrolyte material may comprise lithium, lanthanum, zirconium, and oxygen. The doped lithium-ion solid electrolyte material may comprise Li A La B Zr C O D Where A = 5.0-8.0, B = 2.5-3.0, C = 1.0-2.0, and D = 11-12. A is optionally at least 5.5 and at least 5.8. A is optionally not greater than 7.0 and optionally not greater than 6.8. B is optionally at least 2.5 and optionally at least 2.8. C is optionally at least 1.3 and optionally at least 1.4. C is optionally not greater than 1.8. D is optionally 12. For the avoidance of doubt, the doped lithium-ion solid electrolyte material will contain dopants other than lithium, lanthanum, zirconium, and oxygen.

[0042] The description of the method of the first aspect of the present invention above and below preferably relates to doped lithium lanthanum zirconium oxide.

[0043] One or more dopant materials optionally comprise one or more of the following: alkali metals, alkaline earth metals, transition metals (e.g., Group 4, Group 5, or Group 6 substances), Group 13 substances, Group 15 substances, Group 16 substances, rare earth substances, and lanthanides. This is especially true when the doped lithium-ionized solid electrolyte material is a doped lithium lanthanum zirconium oxide.

[0044] Doped lithium lanthanum zirconium oxide can have the formula Li A La B Zr C O D X E Where A = 5.0-8.0, B = 2.5-3.0, C = 1.0-2.0, and D = 11-12, X is one or more dopants, and E is the total amount of dopants. E is optionally at least 0.01, optionally at least 0.05, optionally at least 0.1, optionally at least 0.15, optionally at least 0.2, optionally at least 0.25, and optionally at least 0.3. E is optionally not greater than 1.0, optionally not greater than 0.9, optionally not greater than 0.8, and optionally not greater than 0.75.

[0045] One or more doped materials optionally include one or more of the following: transition metals, Group 13 materials, Group 15 materials, and Group 16 materials.

[0046] One or more dopant materials optionally include one or more of the following: alkali metals, alkaline earth metals, Group 4 materials, lanthanides, and rare earth materials.

[0047] One or more dopant materials optionally include one or more of the following: alkaline earth metals, Group 4 materials, lanthanides, and rare earth materials.

[0048] One or more dopant materials optionally include one or more of the following: transition metals, Group 13 materials, Group 15 materials and Group 16 materials, and one or more of the following: alkali metals, alkaline earth metals, Group 4 materials, lanthanides and rare earth materials.

[0049] One or more dopant materials optionally include one or more of the following: transition metals, Group 13 materials, Group 15 materials and Group 16 materials, and one or more of the following: alkaline earth metals, Group 4 materials, lanthanides and rare earth materials.

[0050] Optionally, the doped lithium lanthanum zirconium oxide can have the formula Li A La B Zr C O D X1 E1 X2 E2 X1 represents one or more dopants comprising one or more of the following: transition metals, Group 13, Group 15, and Group 16 substances, where A, B, C, and D are as defined above, and E1 represents the total amount of such dopants; X2 represents one or more dopants that are not transition metals, Group 13, Group 15, or Group 16 substances, and E2 represents the total amount of such dopants. E1 is optionally at least 0.01, optionally at least 0.05, optionally at least 0.1, optionally at least 0.15, optionally at least 0.2, optionally at least 0.25, and optionally at least 0.3. E1 is optionally not greater than 0.8, optionally not greater than 0.7, and optionally not greater than 0.6. E2 is optionally at least 0.01, optionally at least 0.05, optionally at least 0.08, optionally at least 0.1, and optionally at least 0.2. E2 is optionally no greater than 0.5, optionally no greater than 0.4, and optionally no greater than 0.3. X2 optionally represents one or more dopants comprising one or more of the following: alkali metals, alkaline earth metals, lanthanides, and rare earth elements.

[0051] One or more dopant materials optionally include one or more of the following: Mo, Nb, Te, Al, Ga, Sb, W, and Ta. Such dopants have been found to be advantageous for LLZO materials.

[0052] One or more dopant materials may optionally contain one or more of the following: Hf, Ti, Sr, Ca, Ba, Mg, Ce, Sc, Y, and Rb. Such dopant can be advantageous for LLZO materials, and may optionally be used in combination with other dopant such as one or more of the following: Nb, Te, Al, Ga, Sb, W, and Ta.

[0053] According to examples, the doped lithium-ion solid electrolyte material can be a doped lithium lanthanum zirconium oxide, wherein one or more dopants optionally include one or more of the following: Nb, Te, Ta, Hf, Ti, Sr, Ca, Ba, Mg, Ce, Sc, Y, Al, Ga, Sb, W, and Rb.

[0054] According to a second aspect of the present invention, a doped lithium-ion solid electrolyte material prepared according to the method of the first aspect of the present invention is also provided. The doped lithium-ion solid electrolyte material of the second aspect of the present invention may include the features described above with respect to the method of the first aspect of the present invention. Preferably, the doped lithium-ion solid electrolyte material of the second aspect of the present invention is or includes doped lithium lanthanum zirconium oxide prepared or prepareable using the method of the first aspect of the present invention.

[0055] According to a third aspect of the present invention, a method for preparing doped lithium lanthanum zirconium oxide is provided, the method comprising: Contact a lithium material (optionally lithium ions) with a solid (optionally a precipitate) containing lanthanum, zirconium, and one or more dopants for incorporation into a solid electrolyte material; The formation of a lithium-containing precipitate can optionally be achieved by providing an anion source capable of forming an insoluble salt with lithium; and The lithium-containing precipitate is calcined to form a doped lithium lanthanum zirconium oxide.

[0056] The method of the third aspect of the invention may include any features of the method of the first aspect of the invention. For example, one or more dopant materials may include those dopant materials mentioned above with respect to the method of the first aspect of the invention. For example, one or more dopant materials may be provided as polyoxometalates.

[0057] According to a fourth aspect of the present invention, a composition for forming a lithium-ionized solid electrolyte material is provided, the composition comprising: A solid (optionally a precipitate) comprising a substance for incorporating into a solid electrolyte material, the substance comprising one or more dopants, said precipitate being substantially free of lithium material (optionally lithium ions); and Lithium material (optionally lithium ions, optionally dissolved in solution).

[0058] Preferably, the lithium-ionized solid electrolyte material is or comprises doped lithium lanthanum zirconium oxide. Preferably, the solid is or comprises a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide, the solid being substantially free of lithium. Preferably, the lithium is or comprises lithium ions dissolved in an aqueous (or at least partially aqueous) solution.

[0059] The composition of the fourth aspect of the present invention may include one or more features described above with respect to the method of the first aspect of the present invention. For example, a solid (optionally a precipitate) containing a substance for incorporating a solid electrolyte material may include the features described above with respect to the method of the first aspect of the present invention. When a solution containing lithium ions is contacted with a solid (optionally a precipitate) containing a substance for incorporating a solid electrolyte material, the composition of the fourth aspect of the present invention may be a composition formed in the method of the first aspect of the present invention. Specifically, the composition of the fourth aspect of the present invention may be formed in a method for producing doped LLZO.

[0060] Therefore, preferably, the composition of the fourth aspect of the invention is or comprises a composition for forming a doped lithium lanthanum zirconium oxide, said composition comprising: A solid comprising lanthanum, zirconium, and one or more dopant materials for incorporating doped lithium lanthanum zirconium oxide, said solid being substantially free of lithium; and Lithium ions dissolved in (preferably aqueous, or at least partially aqueous) solutions.

[0061] Optionally, the composition of the fourth aspect of the invention comprises an anion source that forms an insoluble salt with lithium. Optionally, the anion source that forms an insoluble salt with lithium is or comprises a carbonate anion source.

[0062] According to a fifth aspect of the present invention, a bipartite mixture composition for forming a lithium-ionized solid electrolyte material is improved, the bipartite reaction mixture comprising: The first part comprises: a solid (optionally a precipitate) containing a substance for incorporating a solid electrolyte material, the substance for incorporating the solid electrolyte material comprising one or more dopants, said precipitate being substantially free of lithium material, optionally lithium ions; and The second part includes: lithium material, optionally lithium ions.

[0063] Preferably, the lithium-ionized solid electrolyte material is or comprises doped lithium lanthanum zirconium oxide. Preferably, the first portion of the solid is or comprises a solid containing lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide, said solid being substantially free of lithium. Preferably, the second portion of the lithium is or comprises lithium ions dissolved in (preferably aqueous, or at least partially aqueous) solution.

[0064] The composition of the fifth aspect of the present invention may include one or more features described above with respect to the method of the first aspect of the present invention, and / or one or more features described above with respect to the composition of the fourth aspect of the present invention. For example, a solid (optionally a precipitate) containing a substance for incorporating a solid electrolyte material may include the features described above with respect to the method of the first aspect of the present invention. The composition of the fifth aspect of the present invention may be a composition used in the method of the first aspect of the present invention. Specifically, the composition of the fifth aspect of the present invention may be used in a method for preparing doped LLZO.

[0065] Therefore, the composition of the fifth aspect of the present invention is preferably or comprises a bipartite reaction mixture composition for forming a doped lithium lanthanum zirconium oxide, the bipartite reaction mixture comprising: The first part comprises: a solid containing lanthanum, zirconium, and one or more dopant materials for incorporating doped lithium lanthanum zirconium oxide, said solid being substantially free of lithium; and The second part includes lithium ions dissolved in a solution (preferably aqueous, or at least partially aqueous).

[0066] Optionally, the composition of the fifth aspect of the invention is a three-part reaction mixture composition, further comprising: a third part comprising an anion source that forms an insoluble salt with lithium. Optionally, the anion source that forms an insoluble salt with lithium is or comprises a carbonate anion source.

[0067] According to a sixth aspect of the present invention, a composition for forming a lithium-ionized solid electrolyte material is provided, the composition comprising: A solid (optionally a precipitate) comprising a substance for incorporating a solid electrolyte material, the substance for incorporating the solid electrolyte material comprising one or more dopants, the precipitate optionally comprising lithium; Lithium (optionally lithium ions, optionally dissolved in solution); and Carbonate ion source.

[0068] The composition of the sixth aspect of the present invention may include one or more features described above with respect to the method of the first aspect of the present invention, and / or one or more features described above with respect to the compositions of the fourth and fifth aspects of the present invention.

[0069] Of course, it should be understood that features described with respect to one aspect of the invention can be incorporated into other aspects of the invention. For example, the method of the invention may include any of the features described with reference to the apparatus of the invention, and vice versa.

[0070] The embodiments of the present invention will be described below only through examples. Invention Details The reagents used in the following examples were sourced from the following sources: ZrOCl2·8H2O: Thermo Scientific A12342; La2O3: ACROS Organics 199160010; La(NO3)3·6H2O: VWR 24958.238; 37% HCl: VWR 20252-335; Na2CO3: Tata; K2CO3: VWR 26724.360; Nb2O5: Alfa Aesar 11365-35; Nb2O5·xH2O: CBMM; KOH: VWR 26668.365; K8[Nb6O] 19 [: Stir Nb2O5 or Nb2O5.xH2O in KOH solution at 90-180 °C until it hardly dissolves, then filter out any residual solids, leaving a clear pale blue solution; LiOH.H2O: Alfa Aesar 43171-36; NH4HCO3: Merck 1.01131.5000; (NH4)2Zr(OH)2(CO3)2 solution: Sigma Aldrich 464597.250; (TBA)OH 40% solution: VWR 85738.180; 69% HNO3: VWR 20425.322; (ZrO2)2.CO2.xH2O: Alfa Aesar 43245.36; (NH4)6[Mo7O 24 ].4H2O: VWR 21276.185; LiNO3: VWR 25029.268; Te(OH)6: Alfa Aesar14197.09; Na2WO4.2H2O: HC Starck; Cs2CO3: supplied by Dakram; Ta2O5: Alfa Aesar 14709.18; HfOCl2.8H2O: Alfa Aesar 11833.14; TiOSO4 solution: Sigma Aldrich 495379-1L; SrCl2.6H2O: Alfa Aesar 12494.36; CaCl2.2H2O: ACROS Organics 207780025; BaCl2.2H2O: VWR 21709.364; MgCl2.6H2O: Sigma Aldrich M9272-500G; CeCl3.7H2O: Alfa Aesar A12947.30; ScCl3.6H2O: Alfa Aesar 11218.03; YCl3.6H2O: ACROSOrganics 199180500; Al(NO3)3.9H2O: Alfa Aesar 12360.A1; (NH4) 10 H2W 12 O 42 ].xH2O: HCStarck; (NH4)6[H2W 12 O 40 xH2O: HC Starck; CO2: Air Liquide; K8Ta6O 19 .16H2O – Ta powder and KOH were heated together at 450 °C until a melt was formed. The melt was then extracted into a minimal amount of water to form a clear, colorless solution; Rb2CO3: Sigma Aldrich 8.43858.0010; WO3·2H2O – Na2WO4·2H2O was slowly added to a 20% HCl solution at room temperature and stirred for 4 hours. The resulting yellow precipitate was filtered off and the solution was air-dried.

[0072] Example 1 – MC06-081 – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 via [Nb6O 19 ] 8- Solution A is prepared as follows: Dissolve 128.9 g of 37% HCl and 66.6 g of ZrOCl2·8H2O in 200 ml of DI (deionized) water. Once completely dissolved, add 71.1 g of La2O3 and stir until dissolved. Dilute the solution to 1.5 L with deionized water. For the avoidance of doubt, DI water is deionized water.

[0073] Solution B is prepared as follows: 75.8 g of K8Nb6O is dissolved in deionized water. 19 Solution (30.7% K8Nb6O) 19 Dilute with 15H2O (4.34% KOH) to 500 ml, then add 107.2 g K2CO3. Stir the mixture until completely dissolved.

[0074] Add solution A to solution B at room temperature for 1 hour. Let the mixture age for 40 minutes. Separate the resulting white precipitate by filtration and wash until the conductivity of the filtrate reaches <500 µS.

[0075] The filter cake was then resuspended in a solution of 64.8 g LiOH·H₂O in 500 ml deionized water and stirred until resuspended. A solution of 61.0 g NH₄HCO₃ in 300 ml deionized water was added to the suspended filter cake over 45 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Nb 0.6 O 12 XRD analysis confirmed that its crystal structure is cubic. No impurities were observed. This example demonstrates that doped LLZO can be prepared as follows: a precipitate containing lanthanum, zirconium, and niobium is formed, the precipitate is contacted with lithium ions, and then a carbonate ion source is added, with no observable impurities.

[0076] Example 2 – CO02-104 – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 7.42 g of Nb₂O₅·xH₂O was added to 16.87 g of 40% TBA-OH solution, and the solution was diluted to 50 mL. TBA is (C₄H₁₈)₄N₂O. + The suspension was heated under reflux at 100 °C for 5.5 hours, then cooled to room temperature. The remaining solids were removed by vacuum filtration, leaving a residue containing (TBA)6Nb. 10 O 28 The solution.

[0077] Solution A was prepared as follows: 12.7 g of 37% HCl and 6.59 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.00 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL.

[0078] Composition B was prepared as follows: 74.13 g of (TBA)6Nb was dissolved in deionized water. 10 O 28 Solution (3.28% is (TBA)6Nb) 10 O 28 (1.21% TBA-OH) was diluted to 100 mL. 8.54 g of Na2CO3 was added and stirred until dissolved, resulting in the formation of a white precipitate.

[0079] Solution A was added to composition B and allowed to stand for 1 hour. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0080] The filter cake was resuspended in 50 mL of deionized water, and 6.19 g of LiOH·H₂O was added and dissolved. Separately, 5.83 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 10 hours. The prepared material was pure cubic LLZO. This example demonstrates that doped LLZO can be prepared as follows: a precipitate containing lanthanum, zirconium, and niobium is formed, this precipitate is contacted with lithium ions, and then a carbonate ion source is added, with no observable impurities. Niobium is provided as a polyoxometalate, in this case [Nb 10 O 28 ] 6- .

[0081] Example 3 – CO02-115A – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.7 g of 37% HCl and 6.59 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.00 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL.

[0082] Solution B is prepared as follows: 8.66 g of K8Nb6O is dissolved in deionized water. 19 .15H2O (19.4% is K8Nb6O) 19 Dilute 0.15H₂O (0.87% KOH) to 50 mL. Add 12.4 g of NH₄HCO₃ to the solution and stir until dissolved. Note: Solution B uses bicarbonate ions, unlike Examples 1 and 2 which use carbonate ions.

[0083] Solution A was added to solution B over a period of 1 hour. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0084] The filter cake was resuspended in 50 mL of deionized water and diluted to 100 mL. 6.19 g of LiOH·H₂O was added and dissolved. Separately, 5.83 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was then calcined at 900 °C for 12 hours. The prepared material was cubic LLZO containing small amounts of La₂O₃ and La₂Zr₂O₇ impurities. It is suspected that the impurities are artifacts caused by insufficient mixing during the experiment. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0085] Example 4 – MC07-058C – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.2 g of 37% HCl and 6.32 g of ZrOCl2·8H2O were dissolved in 20 mL of deionized water. Once completely dissolved, 6.72 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 100 mL with deionized water.

[0086] Composition B was prepared as follows: 9.35 g of K8Nb6O was dissolved in deionized water. 19 Solution (21.3% K8Nb6O) 19 Dilute 15H₂O (3.87% KOH) to 100 ml, then add 3.86 g Na₂CO₃ and 4.08 g KOH. Stir the mixture until completely dissolved. After standing, a precipitate will slowly form. Note that carbonate anions and potassium hydroxide are used simultaneously in solution B.

[0087] Solution A was added to composition B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation and washed, then resuspended in a solution of 6.01 g LiOH·H₂O in 40 ml of deionized water. The suspension was stirred until homogeneous. A solution of 5.66 g NH₄HCO₃ in 28 ml of deionized water was added to the suspended filter cake for 40 minutes. The solid was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Nb 0.6 O 12 XRD analysis confirmed its cubic crystal structure. No impurities were formed. Niobium was provided as a polyoxometalate, in this case [Nb6O].19 ] 8- .

[0088] Example 5 – MC07-060C – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.2 g of 37% HCl and 6.33 g of ZrOCl2·8H2O were dissolved in 20 mL of deionized water. Once completely dissolved, 6.72 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 100 mL with deionized water.

[0089] Solution B is prepared as follows: 9.34 g of K8Nb6O is dissolved in deionized water. 19 Solution (21.3% K8Nb6O) 19 Dilute 15H₂O (3.87% KOH) to 100 ml, then add 8.19 g KOH. Stir the mixture until completely dissolved. Note that potassium hydroxide is used in solution B.

[0090] Solution A was added to solution B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation and washed, then resuspended in a solution of 6.01 g LiOH·H₂O in 40 ml of deionized water. The suspension was stirred until homogeneous. A solution of 5.66 g NH₄HCO₃ in 28 ml of deionized water was added to the suspended filter cake for 40 minutes. The solid was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Nb 0.6 O 12 XRD analysis confirmed its cubic crystal structure. No impurities were observed. Niobium was provided as a polyoxometalate, in this case [Nb6O]. 19 ] 8- .

[0091] Example 6 – CO02-122A – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 3.73 g of 69% HNO3 was diluted with 4.85 mL of deionized water to obtain a 30% solution. 6.24 g of [ZrO2]2·CO2·xH2O (40.37% ZrO2) was added to this solution, and the slurry was heated to 50 °C to dissolve the solid, yielding a ZrO(NO3)2 solution. Then, 18.6 g of La(NO3)3·6H2O was dissolved in the solution with stirring. Note that zirconium nitrate and lanthanum nitrate were used.

[0092] Solution B is prepared as follows: 7.89 g of K8Nb6O is dissolved in deionized water. 19 Solution (21.3% K8Nb6O) 19 Dilute 15H2O (3.87% KOH) to 50 mL. Then, dissolve 8.31 g of Na2CO3 in the solution with stirring.

[0093] Solution A was added to solution B at room temperature over 1 hour. The resulting white precipitate was separated by centrifugation and washed, then re-slurryed in 50 mL of deionized water. 6.19 g of LiOH·H₂O was dissolved in the slurry. Separately, 5.83 g of NH₄HCO₃ was dissolved in 27 mL of deionized water with stirring. The NH₄HCO₃ solution was added to the slurry with stirring over 40 minutes. The precipitate was separated by filtration and then dried in an oven at 110 °C. The dried solid was calcined at 900 °C for 12 hours. XRD analysis confirmed its cubic crystal structure with a small amount of La₂Zr₂O₇. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0094] Example 7 – MC07-066C – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.2 g of 37% HCl and 6.72 g of La2O3 were dissolved in 20 ml of deionized water. The solution was then diluted to 100 mL with deionized water.

[0095] Solution B was prepared as follows: 13.09 g of ammonium zirconium carbonate solution (13.6% Zr) was diluted to 100 ml with deionized water, and then 4.63 g of K₂CO₃ was added. The mixture was stirred until completely dissolved, and then 9.33 g of K₈Nb₆O₃ was added. 19 Solution (21.3% K8Nb6O) 19(15H₂O, 3.87% KOH). The solution remains clear and colorless. Note that ammonium zirconium carbonate is used in solution B.

[0096] Solution A was added to solution B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation and washed, then resuspended in a solution of 6.01 g LiOH·H₂O in 40 ml deionized water. The suspension was stirred until homogeneous. A solution of 5.66 g NH₄HCO₃ in 28 ml deionized water was added to the suspended filter cake for 40 minutes. The solid was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Nb 0.6 O 12 XRD analysis confirmed its cubic crystal structure with a small amount of La₂Zr₂O₇ impurity. Niobium is provided as a polyoxometalate, in this case [Nb₆O₂]. 19 ] 8- .

[0097] Example 8 – MC07-025 – Li 6.4 La3Zr 1.48 Nb 0.43 Te 0.09 O 12 K7[TeNb5O 19 Preparation as follows: 0.32 g Te(OH)6 was added to 8.53 g of a mixture containing 1.35 g K8[Nb6O] 19 A solution of 0.07 g KOH and [other ingredients]. Prepare a suspension to approximately 10 ml, then gently stir and heat until a clear, colorless solution is formed. Allow the solution to cool, then seal it in a small vial and let it stand for 3 days before use.

[0098] Solution A was prepared as follows: 14.2 g of 37% HCl and 7.83 g of ZrOCl2·8H2O were dissolved in 20 ml of deionized water. Once completely dissolved, 7.38 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 100 ml with deionized water.

[0099] Solution B is prepared as follows: The entire K7[TeNb5O] solution prepared above is used... 19 Add the solution and 9.72 g Na2CO3 to 100 ml H2O and let it dissolve until a clear, colorless solution is formed.

[0100] Solution A was added to solution B at room temperature over 1 hour. The resulting white precipitate was separated by centrifugation and then resuspended in 7.57 g LiOH·H₂O in 90 ml of deionized water with stirring until resuspended. The suspension was prepared to 150 ml. A solution of 7.13 g NH₄HCO₃ in 33 ml of deionized water was added to the suspended filter cake over 40 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.48 Nb 0.43 Te 0.09 O 12 XRD analysis confirmed its cubic crystal structure. The presence of La₂O₃ impurities is likely due to overloading. Niobium and tellurium are provided as polyoxometalates, in this case [TeNb₅O₂]. 19 ] 7- .

[0101] Example 9 – MC07-058B – Li 6.4 La3Zr 1.4 Ta 0.3 Nb 0.3 O 12 Nominal Cs8[Nb 3.11 Ta 2.89 O 19 The following preparation was performed: 30.11 g Cs₂CO₃, 7.71 g Ta₂O₅, and 5.00 g Nb₂O₅ were manually mixed, then heated to 900 °C and held for 10 hours. The cooled melt was extracted with water to obtain a pale blue, slightly turbid solution with a total mass of 110.5 g. This mixture will contain the general formula [Nb₂O₅]. 6-x Ta x O 19 ] 8- The Lindqvist ions, where x is 0-6. Most ions have x = 2, 3, and 4.

[0102] Solution A was prepared as follows: 12.2 g of 37% HCl and 6.33 g of ZrOCl2·8H2O were dissolved in 20 ml of deionized water. Once completely dissolved, 6.72 g of La2O3 was added and stirred until dissolved. Once dissolved, the solution was diluted to 100 ml with H2O.

[0103] Composition B was prepared as follows: 23.26 g of Cs₂CO₃ and 12.12 g of solution (nominally containing 2.89 g of Cs₈[Nb]) were mixed. 3.11 Ta 2.89 O19 [1.56 g Cs₂CO₃] was dissolved in 90 ml H₂O. The mixture was stirred until Cs₂CO₃ was completely dissolved – Cs₈[Nb₃Ta₃O₃] 19 A slight turbidity remains.

[0104] Solution A was added to composition B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation and washed, then resuspended in a solution of 6.01 g LiOH·H₂O in 40 ml of deionized water and stirred until resuspended. The suspension was prepared to 100 ml. A solution of 5.66 g NH₄HCO₃ in 28 ml of deionized water was added to the suspended filter cake for 40 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Nb 0.3 Ta 0.3 O 12 XRD analysis confirmed its cubic crystal structure. No impurities were observed. Tantalum and niobium were provided as polyoxometalates, in this case [Nb 3.11 Ta 2.89 O 19 ] -8 .

[0105] Example 10 – Preparation of Li by COO2-79B 6.4 La3Zr 1.3 Nb 0.6 Hf 0.1 O 12 Solution A was prepared as follows: 13.2 g of 37% HCl and 6.77 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.23 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.61 g of HfOCl2·8H2O was added, and the mixture was stirred until dissolved.

[0106] Solution B is prepared as follows: 7.45 g of K8Nb6O 19 .15H2O solution (19.4% K8Nb6O) 19 Dilute 0.15H2O (0.87% KOH) to 50 mL. Add 8.82 g of Na2CO3 to the solution and stir until dissolved.

[0107] Solution A was added to solution B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0108] The filter cake was resuspended in 50 mL of deionized water, and 5.83 g of LiOH·H₂O was added and dissolved. Separately, 5.49 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material is cubic LLZO containing a small amount of La₂O₃. Niobium is provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0109] Example 11 – COO2-82A – Preparation of Li 6.4 La3Zr 1.3 Nb 0.6 Ti 0.1 O 12 Solution A was prepared as follows: 13.3 g of 37% HCl and 6.39 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.34 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 1.60 g of TiOSO4 solution (15 wt% TiOSO4, 50 wt% H2SO4) was added, and the mixture was stirred until dissolved.

[0110] Solution B is prepared as follows: 9.08 g of K8Nb6O 19 .15H2O solution (19.4% K8Nb6O) 19 Dilute 0.15H2O (0.87% KOH) to 50 mL. Add 10.50 g of Na2CO3 to the solution and stir until dissolved.

[0111] Solution A was added to solution B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0112] The filter cake was resuspended in 50 mL of deionized water, and 5.90 g of LiOH·H₂O was added and stirred until dissolved. Separately, 5.56 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material is cubic LLZO containing a small amount of La₂O₃. Niobium is provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0113] Example 12 - COO2-29 – Preparation of Li 6.5 La 2.9 Sr 0.1 Zr 1.4 Nb 0.6 O 12 : Solution A was prepared as follows: 12.9 g of 37% HCl and 6.88 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.10 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.40 g of SrCl2·6H2O was added, and the mixture was stirred until dissolved.

[0114] Composition B was prepared as follows: 10.19 g of K8Nb6O was dissolved in deionized water. 19 .15H2O solution (21.3% K8Nb6O) 19 Dilute 15H2O (3.87% KOH) to 50 mL. Add 8.34 g of Na2CO3 and stir until dissolved, resulting in the formation of a white precipitate.

[0115] Solution A was added to composition B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0116] The filter cake was resuspended in 50 mL of deionized water, and 5.97 g of LiOH·H₂O was added and dissolved. Separately, 5.41 g of NH₄HCO₃ was dissolved in 22 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 10 hours. The prepared material was pure cubic LLZO. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0117] Example 13 – COO2-33 – Preparation of Li 6.5 La 2.9 Ca 0.1 Zr 1.4 Nb 0.6 O 12 : Solution A was prepared as follows: 13.0 g of 37% HCl and 7.02 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.14 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.22 g of CaCl2·2H2O was added, and the mixture was stirred until dissolved.

[0118] Composition B was prepared as follows: 10.25 g of K8Nb6O was dissolved in deionized water. 19 .15H2O solution (21.3% K8Nb6O) 19 Dilute 15H2O (3.87% KOH) to 50 mL. Add 8.39 g of Na2CO3 and stir until dissolved, resulting in the formation of a white precipitate.

[0119] Solution A was added to composition B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0120] The filter cake was resuspended in 50 mL of deionized water, and 6.00 g of LiOH·H₂O was added and dissolved. Separately, 5.65 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 10 hours. The prepared material was pure cubic LLZO. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0121] Example 14 – COO2-39 – Preparation of Li 6.75 La 2.75 Ca 0.25 Zr 1.4 Nb 0.5 O 12 : Solution A was prepared as follows: 12.5 g of 37% HCl and 7.53 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 6.88 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.56 g of CaCl2·2H2O was added, and the mixture was stirred until dissolved.

[0122] Composition B was prepared as follows: 8.68 g of K8Nb6O was dissolved in deionized water. 19 .15H2O solution (21.3% K8Nb6O) 19 Dilute 15H2O (3.87% KOH) to 50 mL. Add 8.70 g of Na2CO3 and stir until dissolved, resulting in the formation of a white precipitate.

[0123] Solution A was added to composition B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0124] The filter cake was resuspended in 50 mL of deionized water, and 6.25 g of LiOH·H₂O was added and dissolved. Separately, 5.89 g of NH₄HCO₃ was dissolved in 28 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 10 hours. The prepared material was pure cubic LLZO. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- . Example 15 – COO2-47 – Preparation of Li 6.5 La 2.9 Ba 0.1 Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.8 g of 37% HCl and 6.94 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.05 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.36 g of BaCl2·2H2O was added, and the mixture was stirred until dissolved.

[0125] Composition B was prepared as follows: 11.11 g of K8Nb6O was dissolved in deionized water. 19 .15H2O solution (19.4% K8Nb6O) 19 Dilute 0.15H₂O (0.87% KOH) to 50 mL. Add 8.57 g of Na₂CO₃ and stir until dissolved, resulting in the formation of a white precipitate.

[0126] Solution A was added to composition B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0127] The filter cake was resuspended in 50 mL of deionized water, and 5.95 g of LiOH·H₂O was added and dissolved. Separately, 5.60 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 10 hours. The prepared material was pure cubic LLZO. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0128] Example 16 – COO2-76A – Preparation of Li 6.5La 2.9 Mg 0.1 Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 13.0 g of 37% HCl and 6.95 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.17 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.31 g of MgCl2·6H2O was added, and the mixture was stirred until dissolved.

[0129] Solution B is prepared as follows: Dissolve 8.77 g of Na₂CO₃ in 50 mL of deionized water. Add 2.19 g of K₈Nb₆O₃... 19 .15H2O is added to the solution and stirred until dissolved.

[0130] Solution A was added to solution B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0131] The filter cake was resuspended in 50 mL of deionized water, and 6.02 g of LiOH·H₂O was added and dissolved. Separately, 5.77 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material was cubic LLZO containing a small amount of Li₂CO₃. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- Example 17 – COO2-76B – Preparation of Li 6.5 La 2.9 Ce 0.1 Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.8 g of 37% HCl and 6.84 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.06 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.56 g of CeCl3·7H2O was added, and the mixture was stirred until dissolved.

[0132] Solution B is prepared as follows: Dissolve 8.71 g of Na₂CO₃ in 50 mL of deionized water. Add 2.16 g of K₈Nb₆O₃... 19Add .15H2O to the solution and stir until dissolved.

[0133] Solution A was added to solution B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0134] The filter cake was resuspended in 50 mL of deionized water, and 5.88 g of LiOH·H₂O was added and dissolved. Separately, 5.53 g of NH₄HCO₃ was dissolved in 26 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material was pure cubic LLZO. Niobium was provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0135] Example 18 – COO2-79C – Preparation of Li 6.5 La3Zr 1.3 Nb 0.6 Sc 0.1 O 12 Solution A was prepared as follows: 13.4 g of 37% HCl and 6.38 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.34 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.39 g of ScCl3·6H2O was added, and the mixture was stirred until dissolved.

[0136] Solution B is prepared as follows: 9.08 g of K8Nb6O 19 .15H2O solution (19.4% K8Nb6O) 19 Dilute 0.15H2O (0.87% KOH) to 50 mL. Add 8.76 g of Na2CO3 to the solution and stir until dissolved.

[0137] Solution A was added to solution B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0138] The filter cake was resuspended in 50 mL of deionized water, and 5.97 g of LiOH·H₂O was added and dissolved. Separately, 5.62 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material is cubic LLZO containing a small amount of La₂O₃. Niobium is provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0139] Example 19 – COO2-82B – Preparation of Li 6.4 La 2.9 Y 0.1 Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.9 g of 37% HCl and 6.88 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.10 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL, and 0.46 g of Ycl3·6H2O was added, and the mixture was stirred until dissolved.

[0140] Solution B is prepared as follows: 9.09 g of K8Nb6O 19 .15H2O solution (19.4% K8Nb6O) 19 Dilute 0.15H₂O (0.87% KOH) to 50 mL. Add 8.69 g of Na₂CO₃ to the solution and stir until dissolved.

[0141] Solution A was added to solution B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0142] The filter cake was resuspended in 50 mL of deionized water, and 5.91 g of LiOH·H₂O was added and dissolved. Separately, 5.56 g of NH₄HCO₃ was dissolved in 27 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material is cubic LLZO. Niobium is provided as a polyoxometalate, in this case [Nb₆O₃]. 19 ] 8- .

[0143] Example 20 – MC07-018 – Li 5.8 Al0.4 La3Zr2O 12 [Al] was thus prepared 13 O4(OH) 24 Al(NO3)7. Dissolve 18.76 g of Al(NO3)3·9H2O in H2O to prepare a 100 ml solution. Heat the solution to 50 °C, then add 6.36 g of Na2CO3 over 70 minutes. Maintain the temperature at 50 °C until the solution becomes clear and colorless, then cool the solution to ambient temperature. A solution with a total mass of 105.5 g is obtained.

[0144] Solution A is prepared as follows: 11.60 g of [Al] 13 O4(OH) 12 Dissolve 9.04 g of (NO3)7 solution and 9.04 g of ZrOCl2·8H2O in 20 ml of deionized water. Once completely dissolved, add 12.2 g of 37% HCl and 6.72 g of La2O3, and stir until dissolved. Once dissolved, dilute the solution to 100 ml with H2O.

[0145] Solution B is prepared as follows: Dissolve 9.70 g of Na2CO3 in 100 ml of H2O. Stir the mixture until it is completely dissolved.

[0146] Solution A was added to solution B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation and then resuspended in a solution of 5.60 g LiOH·H₂O in 50 ml deionized water with stirring until resuspended. The suspension was prepared to a volume of 100 ml. A solution of 5.28 g NH₄HCO₃ in 30 ml deionized water was added to the suspended filter cake for 40 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 5.8 Al 0.4 La3Zr2O 12 XRD analysis confirmed that its crystal structure is cubic. Trace amounts of LaAlO3 impurities were present.

[0147] Example 21 – MC07-009B – Li 5.8 Ga 0.4 La3Zr2O 12 Solution A was prepared as follows: 13.1 g of 37% HCl and 9.67 g of ZrOCl2·8H2O were dissolved in 50 ml of deionized water. Once completely dissolved, 7.19 g of La2O3 was added, and the mixture was stirred until dissolved. Once dissolved, 4.56 g of Ga(NO3)3 solution (9.5% Ga, Alfa Aesar, R28G059) was added. The solution was diluted to 100 ml with H2O.

[0148] Solution B is prepared as follows: Dissolve 12.28 g of Na2CO3 in 100 ml of H2O. Stir the mixture until it is completely dissolved.

[0149] Solution A was added to solution B at room temperature over 1 hour. The resulting white precipitate was separated by filtration and washed until the conductivity of the filtrate reached <500 µS.

[0150] The filter cake was then resuspended in a solution of 6.31 g LiOH·H₂O in 50 ml of deionized water and stirred until resuspended. The suspension was prepared to a volume of 100 ml. A solution of 5.94 g NH₄HCO₃ in 30 ml of deionized water was added to the suspended filter cake and allowed to stand for 40 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 5.8 Ga 0.4 La3Zr2O 12 XRD analysis confirmed that its crystal structure is cubic.

[0151] Example 22 - COO2-94C – Li 6.4 La3Zr 1.4 Te 0.3 O 12 Solution A was prepared as follows: 13.1 g of 37% HCl and 8.21 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.21 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL.

[0152] Solution B was prepared as follows: 1.02 g of Te(OH)6 was dissolved in 50 mL of deionized water. 9.27 g of Na2CO3 was added to the solution and stirred until dissolved.

[0153] Solution A was added to solution B over a period of 1 hour. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0154] The filter cake was resuspended in 50 mL of deionized water, and 5.83 g of LiOH·H₂O was added and dissolved. Separately, 5.49 g of NH₄HCO₃ was dissolved in 26 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material was cubic LLZO containing a small amount of La₂O₃ impurity. Example 27 illustrates that doped materials can be prepared without using polyoxometalates to deliver the dopant.

[0155] Example 23 – COO2-89C – Li 6.4 La3Zr 1.4 Sb 0.6 O 12 Solution A was prepared as follows: 13.0 g of 37% HCl and 6.70 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 7.15 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 150 mL.

[0156] Composition B was prepared as follows: 2.17 g of NaSbO3·3H2O was added to 50 mL of deionized water to obtain a white suspension. 9.19 g of Na2CO3 was added to the solution and stirred until dissolved.

[0157] Solution A was added to composition B and allowed to stand for 1 hour. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0158] The filter cake was resuspended in 50 mL of deionized water, and 5.79 g of LiOH·H₂O was added and dissolved. Separately, 5.45 g of NH₄HCO₃ was dissolved in 26 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material was cubic LLZO containing a small amount of La₂O₃ impurities.

[0159] Example 24 – MC07-062C – Li 6.4 La3Zr 1.7 W 0.3 O 12 Solution A was prepared as follows: 4.3 g of 37% HCl and 8.35 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 2.40 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 100 mL.

[0160] Composition B was prepared as follows: 5.19 g of KOH was dissolved in 100 ml of H₂O. 1.17 g of (NH₄) was added. 10 H2W 12 O 42 xH2O (89.1% of which is WO3) is used to form a grayish-white suspension.

[0161] Solution A was added to composition B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation.

[0162] The filter cake was then resuspended in a suspension of 18.29 g LiNO3 in 40 ml deionized water and stirred until resuspended. A solution of 18.29 g NH4HCO3 in 97 ml deionized water was added to the suspended filter cake over 40 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.7 W 0.3 O 12 XRD analysis confirmed that its crystal structure is cubic, containing trace amounts of La₂O₃ and Li₂ZrO₃ impurities. Notably, the La loading was too low to achieve the required stoichiometry. This is because the generated LiHCO₃ solution dissolves a significant amount of Zr and W from the precipitate. We obtained the La₂O₃ content by iteratively finding a suitable value.

[0163] Example 25 - LT02-147 – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 266.1 g of 37% HCl and 137.4 g of ZrOCl2·8H2O were dissolved in 775 ml of deionized water. Once completely dissolved, 146.6 g of La2O3 was added, and the mixture was stirred until dissolved.

[0164] Composition B was prepared as follows: 137.1 g of K8Nb6O was dissolved in deionized water. 19 Solution (31.6% K8Nb6O) 19Dilute with 15H2O (5.44% KOH) to 860 ml, then add 168.5 g Na2CO3. A white precipitate forms.

[0165] Solution A was added to composition B at room temperature for 1 hour. The mixture was then aged for 1 hour. The resulting white precipitate was separated by filtration and washed until the conductivity of the filtrate reached <800 µS.

[0166] The filter cake was then resuspended in a solution of 114.5 g LiOH·H₂O in 850 ml of deionized water and stirred until resuspended. The total volume was prepared to 1750 ml. CO₂ gas was bubbled through the suspension for 75 minutes until the pH dropped to 11.50. The suspension was aged for approximately 45 minutes; if the pH rose above 11.5, additional CO₂ was added. The suspension was then separated by filtration and dried at 110 °C. The dried solid sample was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Nb 0.6 O 12 XRD analysis confirmed that its crystal structure is cubic. No significant amounts of impurities were found. This method may be particularly effective because the solution from which lithium-containing precipitates are removed is a lithium carbonate solution, which can be reused without further purification. This thus reduces lithium loss.

[0167] Example 26 – MC07-020 – Li 6.4 La3Zr 1.4 Nb 0.6 O 12 Solution A was prepared as follows: 12.2 g of 37% HCl and 6.33 g of ZrOCl2·8H2O were dissolved in 20 ml of deionized water. Once completely dissolved, 6.72 g of La2O3 was added and stirred until dissolved. Once dissolved, the solution was diluted to 100 ml with H2O.

[0168] Composition B was prepared as follows: 8.64 g of Na2CO3 was dissolved in 100 ml of H2O. 1.10 g of Nb2O5 (AlfaAesar) was added to form a grayish-white suspension.

[0169] Solution A was added to composition B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation.

[0170] The filter cake was then resuspended in a solution of 6.02 g LiOH·H₂O in 50 ml of deionized water and stirred until resuspended. The suspension was prepared to a volume of 100 ml. A solution of 5.66 g NH₄HCO₃ in 30 ml of deionized water was added to the suspended filter cake and allowed to stand for 40 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Nb 0.6 O 12 XRD analysis confirmed that its crystal structure is cubic. No significant amount of impurities were observed.

[0171] Example 27 – MC07-062B – Li 6.4 La3Zr 1.4 Ta 0.6 O 12 Solution A was prepared as follows: 12.2 g of 37% HCl and 7.68 g of ZrOCl2·8H2O were dissolved in 20 ml of deionized water. Once completely dissolved, 6.72 g of La2O3 was added and stirred until dissolved. Once dissolved, the solution was diluted to 100 ml with H2O.

[0172] Composition B was prepared as follows: 8.64 g of Na2CO3 was dissolved in 100 ml of H2O. 1.82 g of Ta2O5 (AlfaAesar) was added to form a grayish-white suspension.

[0173] Solution A was added to composition B at room temperature for 1 hour. The resulting white precipitate was separated by centrifugation.

[0174] The filter cake was then resuspended in a solution of 6.02 g LiOH·H₂O in 50 ml of deionized water and stirred until resuspended. The suspension was prepared to a volume of 100 ml. A solution of 5.66 g NH₄HCO₃ in 30 ml of deionized water was added to the suspended filter cake and allowed to stand for 40 minutes. The suspension was then separated by filtration and dried at 110 °C. The dried solid was heated to 900 °C and held for 10 hours to obtain Li. 6.4 La3Zr 1.4 Ta 0.6 O 12 XRD analysis confirmed that its crystal structure is cubic and contains a small amount of La2O3 impurities.

[0175] Example 28 – CO02-68 – Li 6.4 La3Zr 1.4 Ta0.6 O 12 Solution A was prepared as follows: 9.0 g of 37% HCl and 4.63 g of ZrOCl2·8H2O were dissolved in 30 mL of deionized water. Once dissolved, 4.95 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 112 mL.

[0176] Solution B was prepared as follows: 5.90 g of Na₂CO₃ was dissolved in 50 mL of deionized water. 1.92 g of K₈Ta₆O₃ was added. 19 Add .16H2O and stir until dissolved.

[0177] Solution A was added to solution B over a period of 1 hour and 40 minutes. The resulting white precipitate was aged for 1 hour, then separated by vacuum filtration and washed.

[0178] The filter cake was resuspended in 50 mL of deionized water, and 4.46 g of LiOH·H₂O was added and dissolved. Separately, 4.20 g of NH₄HCO₃ was dissolved in 20 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was calcined at 900 °C for 12 hours. The prepared material was pure cubic LLZO with a small amount of La₂O₃. Due to weighing errors in this embodiment, the loading of Ta during the reaction was insufficient, which is likely the cause of impurities.

[0179] Example 29 - MC07-068A – Preparation of Li 6.65 La 2.875 Rb 0.125 Zr 1.4 Nb 0.6 O 12 : 9.22 g K8Nb6O 19 .15H₂O was dissolved in 100 ml of deionized water to form a clear, colorless solution. 8.29La(NO₃)₃·6H₂O was dissolved in 50 ml of deionized water to form a clear, colorless solution. Lanthanum nitrate solution was added to potassium hexaniobate solution for 40 minutes, forming a thick white precipitate. The precipitate was washed, centrifuged, and then resuspended in 15 ml of deionized water. 2.43 g of Rb₂CO₃ was added, and the suspension was stirred until homogeneous. The suspension was lyophilized and then calcined at 1000 °C for 10 hours to form RbLaNb₂O₇. XRD analysis showed that the material had a purity of 80%, with the remainder being Rb₂CO₃.

[0180] Solution A was prepared as follows: 9 ml of 36% HCl and 6.33 g of ZrOCl2·8H2O were dissolved in 30 ml of deionized water. Once dissolved, 5.88 g of La2O3 was added, and the mixture was stirred until dissolved. The solution was then diluted to 100 ml.

[0181] Composition B was prepared as follows: 5.44 g of K8Nb6O was dissolved in deionized water. 19 .15H2O solution (21.3% K8Nb6O) 19 Dilute 15H₂O (3.87% KOH) to 100 mL. Add 1.13 g RbLaNb₂O₇ (80% pure, the remainder Rb₂CO₃) and stir to form a homogeneous suspension. Then add 7.28 g Na₂CO₃ and stir until dissolved, resulting in the formation of a white precipitate.

[0182] Solution A was added to composition B and left for 1 hour. The resulting white precipitate was separated by centrifugation and washed.

[0183] The filter cake was resuspended in 40 mL of deionized water, and 6.18 g of LiOH·H₂O was added and dissolved. Separately, 5.82 g of NH₄HCO₃ was dissolved in 28 mL of deionized water and added to the suspended filter cake over 40 minutes. The white suspension was separated by vacuum filtration and dried at 110 °C. The dried solid was then calcined at 900 °C for 10 hours. XRD analysis confirmed that its crystal structure was cubic.

[0184] The effect of pH on the unlithiated precursor material was investigated. Solution A was prepared as follows: 7.01 g of ZrOCl2·8H2O was dissolved in 30 mL of deionized water. 12.7 g of 37% HCl was added to the solution, and then 7.01 g of La2O3 was dissolved in the solution with stirring. The solution was then diluted to 150 mL with deionized water.

[0185] Solution B is prepared as follows: 7.91 g of K8Nb6O is dissolved in deionized water. 19 Solution (21.3% K8Nb6O) 19 Dilute 15H2O (3.87% KOH) to 50 mL. Dissolve 8.12 g of Na2CO3 in the solution with stirring.

[0186] Add solution A to solution B at room temperature over 1 hour. Then adjust the pH of the reaction to the desired value of 3.5–4.5 using 37% HCl. Once a stable pH has been reached, separate and wash the precipitate by centrifugation, then resuspend it in 50 mL of deionized water.

[0187] 6.20 g of LiOH·H₂O was dissolved in the slurry, and the total volume of the slurry was prepared to 100 mL with deionized water. Separately, 5.84 g of NH₄HCO₃ was dissolved in 27 mL of deionized water with stirring. The NH₄HCO₃ solution was added to the slurry with stirring over 40 minutes. The precipitate was separated by filtration and then dried in an oven at 110 °C. The dried solid was calcined at 900 °C for 12 hours.

[0188] At pH 4.0, 4.2, 4.4, and 4.5, cubic lithium lanthanum zirconium niobium oxide (LLZNO) is formed without impurities. At pH 3.6, 3.7, 3.8, and 3.9, cubic lithium lanthanum zirconium niobium oxide (LLZNO) is formed, containing a small amount of impurities. At pH 3.5, cubic LLZNO is not formed.

[0189] The above embodiments describe numerous embodiments of the methods according to the first and third aspects of the present invention, as well as embodiments of doped LLZO according to the second aspect of the present invention. The above embodiments also describe numerous embodiments of the compositions according to the fourth aspect of the present invention, specifically relating to when solution A and composition / solution B have been mixed together to form a precipitate (in the presence of lithium ions). The precipitate formed by mixing solution A with composition / solution B will, at least in the first case, be substantially free of lithium ions.

[0190] The above embodiments also describe numerous embodiments of the composition according to the fifth aspect of the invention, specifically relating to the case where solution A has been mixed with composition / solution B to form a precipitate, which in this case is the first part of the bipartite reactive composition. The lithium-ion solution will constitute the second part of the bipartite reactive composition.

[0191] The above embodiments also describe many embodiments of the composition according to the sixth aspect of the present invention. In this context, mixing solution A with composition / solution B will form a precipitate, which may optionally contain lithium. The composition also contains a lithium ion and carbonate ion source, such as carbon dioxide.

[0192] While the invention has been described and illustrated with reference to specific embodiments, those skilled in the art will understand that the invention is applicable to many different variations not specifically described herein. Some possible variations will now be described, by way of example only.

[0193] The numerous embodiments described above demonstrate that lithium-ion solid electrolyte materials, such as lithium lanthanum zirconium oxide, can be doped with a wide variety of dopants. Those skilled in the art will understand that other dopants can also be used.

[0194] Many of the embodiments described above relate to the production of doped lithium lanthanum zirconium oxide. Those skilled in the art will understand that the teachings of these many embodiments are also applicable to other doped lithium-ion solid electrolyte materials, such as doped lithium aluminum germanium phosphate, doped lithium aluminum titanium phosphate, and doped lithium lanthanum titanate.

[0195] Many of the embodiments described above demonstrate the use of polyoxometalates as one or more dopant sources. Those skilled in the art will understand that other dopant sources can also be used.

[0196] In the foregoing description, whenever integers or elements with known, obvious, or foreseeable equivalents are mentioned, such equivalents are incorporated herein as if they were listed individually. The true scope of the invention should be determined by reference to the claims, which should be interpreted as encompassing any such equivalents. The reader should also understand that integers or features described as preferred, advantageous, convenient, etc., in this invention are optional and do not limit the scope of the independent claims. Furthermore, it should be understood that while such optional integers or features may be beneficial in some embodiments of the invention, they may not be desirable in other embodiments and are therefore optional.

Claims

1. A method for preparing doped lithium lanthanum zirconium oxide, the method comprising: A solution containing lithium ions is brought into contact with a solid, the solid comprising lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide; It forms a precipitate containing lithium; and The lithium-containing precipitate is heated to form the doped lithium lanthanum zirconium oxide.

2. The method of claim 1, wherein the step of forming a lithium-containing precipitate is or includes: Following the contact step, an anion source is provided to form an insoluble salt with lithium, thereby forming a lithium-containing precipitate.

3. The method according to claim 2, wherein the anion source is or comprises a carbonate anion source.

4. The method according to any one of the preceding claims, wherein the lithium-ion-containing solution is an aqueous solution or a partially aqueous solution.

5. The method according to any one of the preceding claims, comprising forming a solid comprising lanthanum, zirconium, and one or more dopant substances for incorporating the doped lithium lanthanum zirconium oxide.

6. The method of claim 5, wherein forming a solid comprising lanthanum, zirconium, and one or more dopant materials for incorporating the doped lithium lanthanum zirconium oxide comprises: Mix at least two solutions, wherein at least one solution contains one or more dopant substances for incorporation into a solid electrolyte material.

7. The method according to claim 5 or 6, wherein the formation of a solid comprising lanthanum, zirconium, and one or more dopant substances for incorporation into the doped lithium lanthanum zirconium oxide is carried out at a pH of at least about 3.

5.

8. The method according to any one of the preceding claims, wherein forming a lithium-containing precipitate comprises: (i) contacting a lithium-ion-containing solution with a solid (optionally a precipitate) containing lanthanum, zirconium, and one or more dopants for incorporating the doped lithium lanthanum zirconium oxide, followed by providing a carbonate ion source; (ii) contacting a solid (optionally a precipitate) containing lanthanum, zirconium, and one or more dopants for incorporating the doped lithium lanthanum zirconium oxide with a carbonate ion source, followed by providing a lithium-ion-containing solution; or (iii) simultaneously contacting a lithium-ion-containing solution and a carbonate ion source with a solid (optionally a precipitate) containing lanthanum, zirconium, and one or more dopants for incorporating the doped lithium lanthanum zirconium oxide.

9. The method according to any one of the preceding claims, wherein at least one substance for incorporating the doped lithium lanthanum zirconium oxide is provided as a polyoxometalate, optionally wherein at least one dopant substance is provided as a polyoxometalate.

10. The method of claim 6 when claim 9 refers to it, wherein at least one of the two solutions comprises a polyoxometalate.

11. The method according to any one of the preceding claims, wherein the doped lithium lanthanum zirconium oxide comprises one or more of aluminum, germanium, and titanium.

12. The method according to any one of the preceding claims, wherein the one or more dopant materials comprise one or more of the following: alkali metals, alkaline earth metals, transition metals (optionally group 4, 5 or 6), group 13, group 15, group 16, rare earth materials and / or lanthanides.

13. The method of claim 12, wherein the one or more dopant materials comprise one or more of the following: transition metals, Group 13 materials, Group 15 materials, and / or Group 16 materials.

14. The method according to claim 12 or 13, wherein the one or more dopant substances further comprise one or more of the following: alkali metals, alkaline earth metals, group IV substances, lanthanides, and / or rare earth substances.

15. A doped lithium lanthanum zirconium oxide prepared or prepared using the method of any one of the preceding claims.

16. A composition for forming a doped lithium lanthanum zirconium oxide, the composition comprising: A solid comprising lanthanum, zirconium, and one or more dopant materials for incorporating the doped lithium lanthanum zirconium oxide, the solid being substantially free of lithium; and Lithium ions dissolved in solution.

17. The composition of claim 16, further comprising an anion source that forms an insoluble salt with lithium.

18. The composition of claim 17, wherein the anion source forming an insoluble salt with lithium is or comprises a carbonate anion source.

19. The composition according to any one of claims 16-18, wherein the lithium ions dissolved in the solution are dissolved in an aqueous solution or a partially aqueous solution.

20. A bipartite reaction mixture composition for forming doped lithium lanthanum zirconium oxide, said bipartite reaction mixture comprising: The first part comprises: a solid containing lanthanum, zirconium, and one or more dopant materials for incorporating said doping lithium lanthanum zirconium oxide, said solid being substantially free of lithium; and The second part contains lithium ions dissolved in the solution.

21. The reaction mixture composition according to claim 20, which is a three-part reaction mixture composition, further comprising: a third part comprising an anion source that forms an insoluble salt with lithium.

22. The reaction mixture composition according to claim 21, wherein the anion source forming an insoluble salt with lithium is or comprises a carbonate anion source.

23. The reaction mixture composition according to any one of claims 20-22, wherein the lithium ions dissolved in the solution are dissolved in an aqueous solution or a partially aqueous solution.