Multi-doped garnet electrolyte

Abstract

In one aspect, the present invention provides a solid electrolyte material. The solid electrolyte material includes a composition of chemical formulas (I), (II), (III), (IV), (V), (VI), (VII), and / or (VIII) as described herein. Another aspect provides a method for manufacturing a green body. A further aspect provides a method for manufacturing a sintered solid electrolyte material. Chemical formula Li 7-3x+y-z Al x La 3-y Ca y Zr 2-z Ta z O 12 of a solid electrolyte material, wherein 0

Description

[Technical Field]

[0001] Reference to related applications This application claims the benefit of U.S. Provisional Application No. 63 / 356,890 filed on 29 June 2022, the disclosures of which are incorporated herein by reference in their entirety.

[0002] Government licensing rights This invention was developed with government support under contract number SP4701-20-F-0115, awarded by the Defense Logistics Agency. The U.S. Government has certain rights to this invention. [Background technology]

[0003] This disclosure relates to solid electrolyte materials suitable for use in solid lithium batteries.

[0004] All-solid-state lithium batteries are created by replacing the highly flammable and unstable liquid electrolyte found in conventional lithium-ion batteries. Solid electrolyte materials can offer many advantages over liquid electrolyte materials. For example, solid electrolyte materials are non-flammable, stable at high temperatures without decomposition, and can be electrochemically stable with respect to lithium metal and / or high-voltage cathodes. This improved stability allows all-solid-state batteries to exhibit higher energy density and power density, enabling the use of desirable electrode materials that were previously difficult to use with liquid electrolytes.

[0005] An ideal solid electrolyte material possesses several desirable properties. For example, an ideal solid electrolyte material may exhibit high ionic conductivity, low / very low electronic conductivity, high chemical and electrochemical stability, resistance to lithium dendrite propagation, and efficient and low-cost manufacturability. In the case of oxide-type solid electrolyte materials, it is necessary that the material is lightweight, contains little to no secondary phases (i.e., phases other than cubic garnet), can be manufactured with low porosity or non-porous properties, and can be sintered in a shorter time and at a lower temperature. The presence of pores in the separator layer of a battery cell can adversely affect the electrochemical performance of the cell and / or battery, as these pores can act as pathways for lithium dendrites to propagate through the solid electrolyte material, potentially causing short circuits. Similarly, secondary phases may not have the same chemical or electrochemical stability as the primary phase (i.e., the cubic garnet phase) of the solid electrolyte material. Therefore, secondary phases can react with the active electrode material during the cell cycle, becoming electronically conductive and potentially causing short circuits.

[0006] Lithium lanthanum zirconium oxide (LLZO) is recognized as a solid electrolyte material that possesses many desirable properties for use in batteries. When properly processed, LLZO has high Li + Ionic conductivity (>10) -5 (S / cm) and low electronic conductivity (~10 -8 It has a saturation ratio (S / cm) and is chemically and electrochemically stable with respect to lithium metal. However, it is difficult to manufacture LLZO as a solid with low porosity and free from harmful secondary phases. Generally, LLZO sintering is carried out at high temperatures (e.g., 1200°C), for long periods (e.g., more than 6 hours), and in the presence of excess lithium to compensate for lithium loss. Lithium loss is due to the volatility of lithium at high temperatures.

[0007] Therefore, the need to provide improved solid electrolyte materials still exists. [Overview of the project]

[0008] The present invention provides a composition of chemical formula (I). including A solid electrolyte material. M1 7-x D1 a M2 3-y D2 b M3 2-z D3 c O 12-w D4 d ···(I) Wherein M1 is Li, M2 is La, M3 is Zr, D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof, D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof, D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof, D4 is F, Cl, Br, I, S, Se, Te, N, P, or any combination thereof, 0 ≦ w ≦ 2, -0.5 < x ≦ 3, 0 ≦ y ≦ 3, 0 ≦ z ≦ 2, 0 ≦ a ≦ 2, 0 ≦ b ≦ 3, 0 ≦ c ≦ 2, and 0 ≦ d ≦ 2, and wherein at least one of a, b, c, and d is not 0.

[0009] In some embodiments, 0 < y ≤ 3, 0 < z ≤ 2, 0 < a ≤ 2, and 0 < b ≤ 3, and 0 < c ≤ 2. In some embodiments, 0 ≤ w ≤ 1. In other embodiments, 0 ≤ w ≤ 0.5. Also, in some embodiments, 0 ≤ w ≤ 0.1.

[0010] In some embodiments, 0 ≤ x ≤ 1. In other embodiments, 0.2 ≤ x ≤ 0.8.

[0011] In some embodiments, 0 < y < 3. In other embodiments, 0 < y < 1. In some embodiments, 0 < y < 0.5. Also, in some embodiments, 0.05 ≤ y ≤ 0.25.

[0012] In some embodiments, 0 < a ≤ 1. In other embodiments, 0 < a < 0.24.

[0013] In some embodiments, 0 < b < 3. In other embodiments, 0 < b < 1. In some embodiments, 0 < b < 0.5. Also, in some embodiments, 0.05 ≤ b ≤ 0.25.

[0014] In some embodiments, 0 < c ≤ 0.7. In other embodiments, 0 < c ≤ 0.5. Also, in some embodiments, 0.2 ≤ c ≤ 0.5.

[0015] In some embodiments, 0 ≤ d ≤ 1. In other embodiments, 0 ≤ d ≤ 0.5. Also, in some embodiments, 0 ≤ d ≤ 0.1.

[0016] In some embodiments, D1 is Al, Fe, Zn, and Ga, or any combination thereof. For example, D1 may be Al. In other embodiments, D1 is Fe. In some embodiments, D1 is Zn. Also, in some embodiments, D1 is Ga.

[0017] In some embodiments, D2 is Ca, Sr, Ba, Bi, and Nd, or any combination thereof. For example, D2 may be Ca. In some embodiments, D2 is Sr. In other embodiments, D2 is Ba. In some embodiments, D2 is Bi. Also in some embodiments, D2 is Ba.

[0018] In some embodiments, D3 is Ta, Nb, W, Ti, and Mo, or any combination thereof. For example, D3 may be Ta. In some embodiments, D3 is Nb. In other embodiments, D3 is W. In some embodiments, D3 is Ti. Also, in some embodiments, D3 is Mo.

[0019] In some embodiments, 7-x=7-a(vD1)+b(3-vD2)+c(4-vD4)-d / 2, where vD1 is the oxidation state of D1, vD2 is the oxidation state of D2, vD3 is the oxidation state of D3, D4 is F, Cl, Br, I, or any combination thereof, y=b, z=c, and w=d. In some embodiments, 0≦x≦1.0.

[0020] Another aspect of the present invention is a composition of chemical formula (II). including We provide solid electrolyte materials. Li 7-x D1 a La 3-y D2 b Zr 2-z D3 c O 12-w D4 d ...(II) During the ceremony, D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof. D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof. D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Te, I, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof, D4 is F, Cl, Br, I, S, Se, Te, or any combination thereof, 0 ≦ w < 2, -0.5 < x ≦ 3, 0 < y ≦ 3, 0 < z ≦ 2, 0 < a ≦ 2, 0 < b ≦ 3, 0 < c ≦ 2, and 0 ≦ d ≦ 2. ​​​​​​​​​​​​​​​​​​​​​​In some embodiments, D2 is Ca, Sr, Ba, or any combination thereof. For example, D2 may be Ca. In other embodiments, D2 is Sr. Also, in some embodiments, D2 is Ba.

[0027] In some embodiments, D3 is Ta, Nb, W, Ti, and Mo, or any combination thereof. For example, D3 may be Ta. In some embodiments, D3 is Nb. In other embodiments, D3 is W. In some embodiments, D3 is Ti. Also, in some embodiments, D3 is Mo.

[0028] In some embodiments, D4 is F, Cl, or any combination thereof. For example, D4 may be F. In other embodiments, D4 may be Cl.

[0029] In some embodiments, 0 < a ≤ 0.25. In some embodiments, 0 < b ≤ 0.5. In some embodiments, 0 < c ≤ 1.0. Also, in some embodiments, 0 ≤ d ≤ 0.25.

[0030] In some embodiments, 0 ≤ x ≤ 1.0. In some embodiments, 0 ≤ y ≤ 0.5. In some embodiments, 0 ≤ z ≤ 1.0. Also, in some embodiments, 0 ≤ w ≤ 0.25.

[0031] In some embodiments, 7 - x = 7 - a(vD1)+b(3 - vD2)+c(4 - vD4)-d / 2, where vD1 is the oxidation state of D1, vD2 is the oxidation state of D2, vD3 is the oxidation state of D3, D4 is F, Cl, Br, I, or any combination thereof, y = b, z = c, and w = d. In some embodiments, 0 ≤ x ≤ 1.0.

[0032] Another aspect of the present invention provides a composition of chemical formula (IV) including solid electrolyte material. Li n Bx vB La 3-y C y vC Zr 2-z D z vD O 12-a G a ···(IV) In the formula, n = 7 - x(vB)+y(3 - vC)+z(4 - vD)-a / 2, where vB is the oxidation state of B, vC is the oxidation state of C, and vD is the oxidation state of D, B is H + , Al 3+ , Ga 3+ , Fe 3+ , Zn 2+ , Ge 4+ or any combination thereof, C is Ca<000(0037>, Ba 2+ , Sr 2+ , Mg 2+ , Rb + , Ce 4+ or any combination thereof, ]5D is Ta 5+ , Y 3+ , Mo 6+ , Nb 5+ , W 6+ , Ge 4+ , Ti 4+ or any combination thereof, G is F - , Cl - , Br - , I - or any combination thereof, 0 < x < 0.24, 0 < y ≤ 1.0,[[ID=?9]] 0 < z ≤ 1.0, and 0 ≤ a ≤ 1.0.

[0033] ' In some embodiments, B is Al 3+ ]5In some embodiments, C is Ca 2+ In some embodiments, D is Ta 5+ , Nb 5+ , Ti 4+or any combination thereof. In some embodiments, D is Ta 5+ is.

[0034] In some embodiments, 0 < x < 0.15. In other embodiments, 0.02 < x < 0.10.

[0035] In some embodiments, 0 < y < 0.50. In other embodiments, 0.1 < y < 0.30. In some embodiments, 0.15 < y < 0.28.

[0036] In some embodiments, 0 < z < 0.70. In other embodiments, 0.3 < z < 0.6. In some embodiments, 0.4 < z < 0.55.

[0037] In some embodiments, 0 ≤ a < 0.1. In other embodiments, 0 ≤ a < 0.05. In some embodiments, x, y, z, and a are selected such that 6 ≤ n ≤ 7.

[0038] In one aspect, the present invention provides a composition of chemical formula (V) including solid electrolyte material. Li 7-x B a La 3-y C b Zr 2-z D c O 12 ···(V) wherein, B is Al or Ga, C is Ca, Sr, Ba, or Mg, D is Ta, Nb, W, Mo, or Ti, 0 ≤ x ≤ 1, 0 < a < 0.24, 0 < y ≤ 0.5, 0 < b ≤ 0.5, 0 < z ≤ 1, and 0 < c ≤ 1.

[0039] Another aspect of the present invention is a composition of chemical formula (VI)including To provide a solid electrolyte material. Li 7+y-z La 3-y Ca y Zr 2-z Ta z O 12 ···(VI) Wherein, 0 < y < 0.3, and 0.2 < z < 0.6.

[0040] In other embodiments, the present invention provides a composition of chemical formula (VII) including To provide a solid electrolyte material. Li 7-3x+y-z Al x La 3-y Ca y Zr 2-z Ta z O 12 ···(VII) Wherein, 0 < x < 0.15, 0 < y < 0.3, and 0.2 < z < 0.6.

[0041] Another aspect of the present invention is a composition of chemical formula (VIII) including To provide a solid electrolyte material. Li 7-3x+y-z B x La 3-y Ca y Zr 2-z Ta z O 12 ···(VIII) Wherein, B is Al, 0 ≤ x < 0.25, $0 < y \leq 0.5$, and $0 < z \leq 1$.

[0042] In some embodiments, $0 \leq x < 0.15$. In other embodiments, $x$ is 0. Also, in some embodiments, $0 < x < 0.25$.

[0043] In some embodiments, 0 < y < 0.3. In other embodiments, 0.2 < z < 0.6.

[0044] In some embodiments, a composition of Chemical Formula (I), (II), (III), (IV), (V), (VI), (VII), or (VIII) including The solid electrolyte material is at least about 4×10 -4 S / cm of Li + conductivity.

[0045] Another aspect of the present invention provides an electrode for a solid battery including a composition of Chemical Formula (I), (II), (III), (IV), (V), (VI), (VII), or (VIII) including solid electrolyte material.

[0046] Another aspect of the present invention provides a two - layer solid electrolyte structure including a porous layer and a high - density layer. At least one of the porous layer and the high - density layer is a composition of Chemical Formula (I), (II), (III), (IV), (V), (VI), (VII), and / or (VIII) including solid electrolyte material.

[0047] Another aspect of the present invention provides a three - layer solid electrolyte structure including a first porous layer, a high - density layer, and a second porous layer. At least one of the first porous layer, the high - density layer, and the second porous layer is a composition of Chemical Formula (I), (II), (III), (IV), (V), (VI), (VII), and / or (VIII) including solid electrolyte material.

[0048] Another aspect of the present invention provides a solid battery including the solid electrolyte material described herein, the electrode described herein, the two - layer solid electrolyte structure described herein, or the three - layer solid electrolyte structure described herein.

[0049] In some embodiments, the solid electrolyte material is sintered. In some embodiments, the sintered electrolyte material is incorporated into a ceramic separator. In some embodiments, the sintered electrolyte material is incorporated into a host structure for lithium metal plating and stripping. In some embodiments, the sintered electrolyte material is in physical contact with the cathode material and anode material to form an electrode pair and separator layer combination.

[0050] In other embodiments, the present invention provides a method for forming an unsintered body comprising a solid electrolyte material as described herein.

[0051] In another aspect, the present invention provides a method for forming an unsintered body comprising the sintered solid electrolyte material described herein.

[0052] The following diagrams are provided as examples only and are not intended to limit the scope of the claimed invention. [Brief explanation of the drawing]

[0053]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

[0054] The present invention provides a solid electrolyte material, a battery cell containing such a solid electrolyte material, and a method for forming such a solid electrolyte material.

[0055] Where used herein, unless otherwise specified, the following definitions shall apply:

[0056] I. Definition The terms used herein are intended solely to describe and not to limit specific exemplary configurations. Where used herein, the singular articles “a,” “an,” and “the” may also include the plural unless otherwise clearly indicated in the context. The terms “comprises,” “comprising,” “including,” and “having” are inclusive and thus indicate the presence of features, steps, actions, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, actions, elements, components, and / or groups thereof. Method steps, processes, and actions described herein should not be construed as necessarily requiring their execution in a specific order described or illustrated unless specifically identified as the order of execution. Additional or alternative steps may be used.

[0057] In this specification, terms such as "first," "second," and "third" may be used to describe various elements, components, regions, layers, and / or sections. These elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may only be used to distinguish one element, component, region, layer, or section from another region, layer, or section. Terms such as "first," "second," and other numerical terms do not imply a sequence or order unless explicitly indicated by the context. Thus, a first element, component, region, layer, or section described below may be referred to as a second element, component, region, layer, or section without deviating from the teaching of the exemplary configuration.

[0058] As used herein, when an element is described as “adjacent,” “engaged,” “connected,” “attached,” or “linked” to another element, it may be directly adjacent, engaged, connected, attached, or linked to the other element, or there may be an intervening element. In contrast, when an element is described as “directly adjacent,” “directly engaged,” “directly connected,” “directly attached,” or “directly linked” to another element, there may be no intervening element or layer. Other words used to describe relationships between elements should be interpreted similarly (e.g., “between” and “directly between,” “adjacent” and “directly adjacent”). As used herein, the term “and / or” includes any combination of one or more of the listed related items.

[0059] As used herein, the term “doping” and its derivatives refer to the presence or arrangement of atoms other than the fundamental atoms in the crystal structure of garnet materials. For example, Li7La3Zr2O 12In the (LLZO) base structure, some or all of lithium, some or all of lanthanum, some or all of zirconium, and / or some or all of oxygen can be substituted with other atoms. Such substitutions can be made after or during the formation of the base structure. Similar substitutions can be made in other garnet-based structures.

[0060] As used herein, the term "garnet" refers to the cubic or tetragonal structure of LLZO.

[0061] As used herein, the term “solid electrolyte material” refers to a material suitable for use in solid-state battery cells. A solid electrolyte material is a composition of chemical formula (I), (II), (III), (IV), (V), (VI), (VII), or (VIII). including .

[0062] As used herein, the term “unsintered body” refers to an unfired body containing a solid electrolyte material (e.g., tape and / or film).

[0063] As used herein, the term “powder bed” refers to a lithium-containing powder located near a component or unsintered body that is to be sintered or otherwise heat-treated. The powder may consist of undoped LLZO, doped LLZO, or other lithium-containing material. This can act as a reservoir for supplying additional lithium during heat treatment and can suppress the loss of lithium from the component or unsintered body during sintering or other thermal processes.

[0064] As used herein, the term “porosity” refers to the ratio of the volume of space not occupied by the material (e.g., a solid electrolyte material) to the total volume of the material in question, unless the context indicates otherwise. In some embodiments, space at the edges of the material in question (e.g., depressions on the outer surface of the material in question) is not included in the determination of porosity.

[0065] As used herein, the term "stabilization of the cubic phase" refers to stabilizing the cubic crystal structure of a solid electrolyte material and preventing a transition from the cubic phase to the tetragonal phase (e.g., during processing), unless the context indicates otherwise. Stabilization may be complete (i.e., no transition) or partial by reducing the amount of transition that occurs as compared to the condition without the same material and the same amount of stabilizing material.

[0066] As used herein, the term "secondary phase" refers to an undesired composition formed within a structure, unless the context indicates otherwise. The secondary phase can be non-garnet or garnet. In the case of a secondary phase garnet, its composition may be different from that desired or it may have a dopant located at an incorrect site. Often, the secondary phase can impair the structural or performance characteristics of the solid electrolyte material. For example, the secondary phase can cause an increase in impedance or a weakness in the structural characteristics of the solid electrolyte material. Exemplary secondary phases include, but are not limited to, Li2O, Li2CO3, Al2O3, LiAlO2, La2Zr2O7, LaTaO4, CaO, CaCO3, ZrO2, Li2ZrO3, Li3BO3, Li-Ca-B-O, etc. Multiple secondary phases can be present.

[0067] II. Solid Electrolyte Material In one aspect, the present invention provides a solid electrolyte.

[0068] A solid electrolyte ideal for battery applications has a high ionic conductivity (10 -4Solid electrolytes must possess a conductivity (greater than S / cm), low processing energy and cost, minimal waste during manufacturing, and high chemical and electrochemical stability. The physical and electrochemical properties of a solid electrolyte are primarily determined by the composition, crystalline phase, and microstructure of the sintered body. These properties include electronic and ionic conductivity, electrochemical stability (relative to lithium metal and other cathode and anode materials), sintering temperature, lithium vapor pressure, and mechanical properties. Processing conditions such as sintering time, sintering temperature, heating rate, and additives such as sintering aids also affect the physical and electrochemical properties of the solid electrolyte.

[0069] LLZO's properties can be tuned using elemental doping. Generally, the use of a single dopant alters the properties of LLZO, improving some in desirable ways while degrading and / or remaining unaffected others. The use of multiple dopants allows for control over the addition of final properties by combining them in a way that they do not negatively interfere with each other. When using two dopants, the added degrees of freedom allow for the improvement of some material properties in desirable ways while offsetting undesirable changes. When using three or more dopants, an optimized composition that is nearly ideal in all categories can be created, provided that the final material remains stable with all dopants added. To date, the best properties of LLZO reported have been achieved by doping with one or two elements.

[0070] Generally, each site in a crystal has a limit to the number of dopants that can be substituted for each dopant associated with that site before a secondary phase appears. In some cases, using dopants at multiple crystal sites can broaden the solubility window and allow for additional amounts of dopants compared to single-site doping without the formation of secondary phases and / or impurities. Secondary phases and / or impurities can reduce ionic conductivity, interact with or react with the Li metal, and / or cause short circuits during manufacturing or operation. Then, by doping three elements at three sites, it becomes possible to introduce a larger total amount of dopants compared to the case of two, and similarly for additional dopants.

[0071] LLZO garnet electrolytes exist in two crystalline phases: cubic and tetragonal. The cubic phase has an ionic conductivity more than two orders of magnitude higher than the tetragonal phase and is the preferred phase for battery applications. The cubic phase has higher entropy than the tetragonal phase and is more stable at higher temperatures. However, the tetragonal phase of undoped LLZO is stable at room temperature. Doping with Ta or Al has been shown to stabilize the cubic phase at room temperature. Other elements such as Ga and Nb have also been used to successfully stabilize the cubic phase of LLZO. Generally, these dopants create lithium vacancies, increasing the entropy of the mixture and contributing to the stabilization of the cubic phase. When dopants are used to stabilize the cubic phase of LLZO, the ionic conductivity at room temperature is 10 -4 It has been demonstrated that it exceeds S / cm.

[0072] Sintering LLZO typically requires high temperatures (>1200°C) to sinter ceramics, i.e., to create a low-porosity microstructure with a uniform composition. In the case of LLZO, lithium in the composition has a very high vapor pressure at these temperatures. Evaporation of Li creates a compositional gradient, hindering proper sintering and firing and potentially causing decomposition of the garnet crystal structure. Powder beds containing excess lithium are typically used in the form of additional LLZO powder, but are usually used in a sintering environment to limit the loss of lithium from the components being sintered. After sintering, the powder bed is lithium-deficient and is generally disposed of as waste. Furthermore, the porous garnet layer may collapse at these high temperatures in some embodiments and under certain conditions, which may be due to liquid-phase sintering or softening / creep of the LLZO at the sintering temperature. Lowering the sintering temperature while still achieving the desired (low or high) porosity and single-phase microstructure reduces both energy and material costs by reducing or eliminating the need for a powder bed.

[0073] Some dopants have little effect on the sintering temperature compared to undoped LLZO. However, Al-doped LLZO has been shown to have a lower sintering temperature (i.e., below 1200°C) and improved density (i.e., reduced porosity after sintering). While we do not wish to be bound by theory, these properties of Al-doped LLZO may be due to the formation of a transient liquid phase containing Li and Al, which alters the sintering rate during liquid-phase sintering. Alternatively, these properties of Al-doped LLZO may also be due to how Al affects the volatility of lithium in the LLZO. The amount of Al required to stabilize the cubic phase is more than approximately 0.15 moles of Al per formula unit (pfu), i.e., Li 6.55 Al 0.15 La3Zr2O 12However, the amount of Al required to act as a sintering aid can be much less. When LLZO is doped with more than about 0.15 pfu of Al, Al-rich regions are observed at the grain boundaries, which correlate with instability to lithium metal during cell cycling.

[0074] In many cases, Al is introduced into the LLZO material during firing or sintering by using a crucible rich in Al2O3, which is reactive with LLZO. When a very high-purity Al2O3 crucible is used during firing, for example, up to about 0.24 pfu or more of Al can be added to the LLZO. In this type of process, the amount of Al cannot be precisely controlled. Instead, in some embodiments, the addition of a controlled amount of Al may be achieved by firing and / or sintering on a substrate containing less than about 5% Al2O3 using a desired amount of Al-containing precursor material before firing.

[0075] In some embodiments, the Al content is limited to well below about 0.1 pfu to prevent segregation at grain boundaries. While we do not wish to be bound by theory, the presence of Al below about 0.15 pfu, below about 0.12, or below about 0.10 pfu, and in some embodiments, about 0.01 to 0.08 pfu, is thought to significantly improve density and reduce the porosity of the sintered LLZO without forming an unstable secondary phase.

[0076] Furthermore, although not wishing to be bound by theory, restricting Al doping to less than about 0.15 pfu (e.g., less than about 0.12 pfu, less than about 0.10 pfu, and in some embodiments, from about 0.01 pfu to about 0.08 pfu) is thought to benefit LLZO by acting as a sintering aid, minimizing porosity without creating Al-rich grain boundaries, and beneficially reducing the sintering temperature. However, this small amount of Al is not sufficient to stabilize the cubic phase of LLZO. Additional dopants can be used in combination with Al to stabilize the cubic phase. For example, Ta can be co-doped with Al to stabilize the cubic phase, where Al is doped at the Li site and Ta is doped at the Zr site. Generally, Ta doping above about 0.2 pfu (e.g., above about 0.35 pfu, or above about 0.4 pfu and less than about 0.6 pfu) can be used to stabilize the cubic phase. Al 3+ and Ta 5+ are both in a higher oxidation state than the elements they replace (Li 1+ and Zr 4+ ), respectively), so this level of doping creates a large number of Li vacancies, along with a reduction in the amount of lithium in the crystal structure. This reduction in lithium can have an adverse effect on physical properties (e.g., Li + conductivity) because there is a significant reduction in the lithium present for conduction. Adding a third dopant with a lower valence than La 3+ at the La 3+ site, such as Ca 2+ or Sr 2+ , can fill the vacancies created by the other dopants and allow more lithium to be added to the composition. For example, in a system doped with about 0.1 pfu of Al and about 0.4 pfu of Ta, about 0.7 pfu of lithium vacancies are created and about 6.3 pfu of Li remains. When about 0.2 pfu of Sr is doped at the La site, about 6.5 pfu of Li results in the correct stoichiometry (i.e., Li 6.5 Al<00001​​​​​​​​​12 ).

[0077] In some embodiments, if the type and amount of dopants are appropriately selected, an increase in conductivity beyond that which can be found with only two dopants can be achieved. In this example, the first dopant is used to stabilize the cubic phase, another dopant is used as a sintering aid, and the third dopant is used to bring the lithium content to a desired level. By doping with the three elements described herein, the sintering temperature can be reduced, the density can be improved / porosity can be reduced with little or no detection of the secondary phase, and Li can be increased without sacrificing other beneficial properties of LLZO. + Ionic conductivity can be optimized. When multiple elements are doped, unexpected "cocktail" effects may occur, such as unexpected changes in mechanical properties like flexural strength, modulus of elasticity, or hardness; unexpected changes in physical properties like reduced volatility of lithium at high temperatures (e.g., during and after sintering), the requirement for lower sintering temperatures, or the formation of a low-temperature eutectic phase; or unexpected changes in electrochemical properties such as significant changes in ionic or electronic conductivity, stability to water, air, CO2, or other materials, or other unexpected benefits.

[0078] The properties can be further tuned as needed by using different dopants, or more than three additional dopants. For example, the ability to control properties such as increasing porosity may be desirable in some cases. By appropriately changing the composition of LLZO, the sintering temperature and densification rate can be modified, enabling control of porosity. Furthermore, a high-density porous bilayer microstructure (i.e., a low-porosity layer adjacent to a high-porosity layer) can be achieved if the optimal composition for each layer is appropriately selected.

[0079] This approach provides a multi-element doping strategy using LLZO containing three or more dopants to optimize the aforementioned combination of physicochemical properties for use as a lithium-conducting solid electrolyte. After sintering, the composition of a particular embodiment is 4 × 10-4 High Li exceeding S / cm + It may have conductivity, very low and controllable porosity, and a secondary phase that is little to no detectable. Furthermore, certain embodiments in line with a multi-element doping strategy may have unexpected properties, such as low lithium volatility at high temperatures. This can provide the ability to sinter with less (or no) excess lithium exceeding the stoichiometric amount to compensate for lithium loss. This property can also provide the ability to sinter without using a powder bed or other lithium source outside the unsintered body to compensate for lithium loss during sintering.

[0080] When using more than one dopant, the entropy of the mixture tends to be higher than when using two or fewer dopants, based on the following formula.

number

[0081] Because the cubic phase of garnet is a higher entropy phase than the tetragonal phase, the stability of the cubic phase can be increased by using three or more dopants. Furthermore, entropy can be increased by using dopants that create lithium or oxygen vacancies in the crystal structure. This can result in lower firing or sintering temperatures for cubic LLZO. Disorder is advantageous for a more symmetrical cubic phase. Using three or more dopants increases disorder compared to using two, one, or no dopants, but still maintains a single cubic garnet phase, for example, by eliminating or reducing the formation or presence of secondary or impurity phases.

[0082] In a particular embodiment, O 2-Anions can be doped into a crystal structure by replacing some of the atoms with one or more anions. An example of anion is F - Cl - Examples include, and any combination thereof. Anionic doping may have similar effects to cationic doping. Anionic doping may have the additional advantage of making the garnet surface more stable for reactions in both calcined powder products and sintered products. The product may be more stable to air, i.e., ambient H2O and CO2, and may have a more stable interface with the electrode material.

[0083] This approach includes a method for producing multi-doped LLZO garnet compositions. In some embodiments, the composition may be produced by blending precursors together and calcining them at a set temperature and for a set amount of time to produce a doped garnet material. The precursors may be salts, carbonates, oxides, nitrates, and / or hydroxides of desired elements to the doped garnet material. After calcination, the doped garnet material may be optionally pulverized to reduce the particle size. The doped garnet material can be produced into desired structures by sintering or forming composites with polymers, ceramics, glass, conductive carbon, or other materials, including but not limited to other ion-conducting materials. Calcination and sintering may be achieved in the same or separate processing steps.

[0084] The approach of the present invention is based on the "Co-sinterable lithium garnet-type oxide electrolyte with" by S. Ohta et al. cathode for all-solid-state lithium ion This approach has considerable advantages over modern LLZO technologies such as "battery" (J. Power Sources 2014, No. 265, pp. 40-44) and US Patent Application Publication 2015 / 0056519, filed August 20, 2014, all of which are incorporated by reference. Firstly, Ohta's powder product, which is pre-sintered, is doped with two elements (Ca and Nb) instead of three or more. In preparation for sintering, Ohta teaches that the powder is mixed with Al2O3 and Li3BO3 as processing additives, rather than as substitutions or dopants. This is a significant disadvantage compared to this approach. When doping with elements such as Al, it is necessary to reduce the corresponding amount of Li from the composition so that excess material exceeding the stoichiometric composition does not form a secondary phase, while still ensuring space for Al to enter the crystal lattice. Generally, doping is performed during the synthesis or calcination step to produce the LLZO product. On the other hand, Ohta teaches that elements are added as "additives" after the calcination step. Furthermore, it has been shown that the Al2O3 and Li3BO3 additives do not form a single-phase low-porosity product, but rather remain as a secondary phase after sintering. This can be seen in Ohta's SEM-EDX images, which clearly show regions with high B and Ca content, distinct from the LiLaZrNbAl region. Ohta's final composition in the sintered product is a two-element doped LLZO (doped with Al and Nb) with Li-Ca-BO grain boundary products generated during sintering. This approach does not involve the use of additives containing element B, or inorganic elements not already present in the doped LLZO composition, as it does not have such grain boundary products.

[0085] This approach offers significant advantages over current LLZO technologies such as those described in Japanese Patent Publication No. 2021-093308. This reference discloses a method for producing crystalline grain aggregates composed of calcined but unsintered LLZO material. However, this approach details multi-doped LLZO powder and multi-doped LLZO sintered structures. Furthermore, while this reference discloses a formula that may include three dopants, it does not disclose a doping strategy that would guide the selection of the type and amount of each dopant, or how to balance the dopants with the elements Li, La, Zr, and O in the composition, nor does it disclose any explanation of the relationship between dopants and their influence on their properties. Moreover, in all embodiments, two or fewer dopants are used. Therefore, this reference does not teach a meaningful method for doping LLZO with three or more elements. This approach teaches a method for producing multi-doped LLZO powder and sintered products, with a detailed emphasis on how to combine dopants and balance the composition to achieve the desired results.

[0086] Some embodiments of the present invention relate to a composition of chemical formula (I). including We provide solid electrolyte materials. M1 7-x D1 a M2 3-y D2 b M3 2-z D3 c O 12-w D4 d ...(I) During the ceremony, M1 is Li, M2 is La, M3 is Zr, D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof. D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof. D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof, D4 is F, Cl, Br, I, S, Se, Te, N, P, or any combination thereof, 0 ≦ w ≦ 2, -0.5 < x ≦ 3, 0 ≦ y ≦ 3, 0 ≦ z ≦ 2, 0 ≦ a ≦ 2, 0 ≦ b ≦ 3, 0 ≦ c ≦ 2, and 0 ≦ d ≦ 2, where at least one of a, b, c, and d is not zero.

[0087] In some embodiments, 0 < y ≦ 3, 0 < z ≦ 2, 0 < a ≦ 2, 0 < b ≦ 3, and 0 < c ≦ 2.

[0088] In some embodiments, 0 ≦ w ≦ 1. In other embodiments, 0 ≦ w ≦ 0.5. Also, in some embodiments, 0 ≦ w ≦ 0.1.

[0089] In some embodiments, 0 ≦ x ≦ 1. In other embodiments, 0 ≦ x ≦ 1. Also, in some embodiments, 0.2 ≦ x ≦ 0.8.

[0090] In some embodiments, 0 < y < 3. In other embodiments, 0 < y < 1. In some embodiments, 0 < y < 0.5. Also, in some embodiments, 0.05 ≦ y ≦ 0.25.

[0091] In some embodiments, 0 < a ≦ 1. In other embodiments, 0 < a < 0.24.

[0092] In some embodiments, 0 < b < 3. In other embodiments, 0 < b < 1. In some embodiments, 0 < b < 0.5. Also, in some embodiments, 0.05 ≤ b ≤ 0.25.

[0093] In some embodiments, 0 < c ≤ 0.7. In other embodiments, 0 < c ≤ 0.5. Also, in some embodiments, 0.2 ≤ c ≤ 0.5.

[0094] In some embodiments, 0 ≤ d ≤ 1. In other embodiments, 0 ≤ d ≤ 0.5. Also, in some embodiments, 0 ≤ d ≤ 0.1.

[0095] In some embodiments, D1 is Al, Fe, Zn, and Ga, or any combination thereof. For example, D1 may be Al. In other embodiments, D1 is Fe. In some embodiments, D1 is Zn. Also, in some embodiments, D1 is Ga.

[0096] In some embodiments, D2 is Ca, Sr, Ba, Bi, and Nd, or any combination thereof. For example, D2 may be Ca. In some embodiments, D2 is Sr. In other embodiments, D2 is Ba. In some embodiments, D2 is Bi. Also, in some embodiments, D2 is Ba.

[0097] In some embodiments, D3 is Ta, Nb, W, Ti, and Mo, or any combination thereof. For example, D3 may be Ta. In some embodiments, D3 is Nb. In other embodiments, D3 is W. In some embodiments, D3 is Ti. Also, in some embodiments, D3 is Mo.

[0098] In some embodiments, 7 - x = 7 - a(vD1)+b(3 - vD2)+c(4 - vD4)-d / 2, where vD1 is the oxidation state of D1, vD2 is the oxidation state of D2, vD3 is the oxidation state of D3, D4 is F, Cl, Br, I, or any combination thereof, y = b, z = c, and w = d. In some embodiments, 0 ≦ x ≦ 1.0.

[0099] Other embodiments of the present invention provide a composition of chemical formula (II) including a solid electrolyte material. Li 7-x D1 a La 3-y D2 b Zr 2-z D3 c O 12-w D4 d ···(II) wherein, D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof, D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof, D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Te, I, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof, D4 is F, Cl, Br, I, S, Se, Te, or any combination thereof, 0 ≦ w < 2, -0.5 < x ≦ 3, 0 < y ≦ 3, 0 < z ≦ 2, 0 < a ≦ 2, 0 < b ≦ 3, 0 < c ≦ 2, and 0 ≦ d ≦ 2.

[0100] In some embodiments, 0 ≦ w ≦ 1. In other embodiments, 0 ≦ w ≦ 0.5. Also, in some embodiments, 0 ≦ w ≦ 0.1.

[0101] In some embodiments, 0 < x ≦ 1.5. In some embodiments, 0.0 < y ≦ 2. In other embodiments, 0.5 < y ≦ 2. Also, in some embodiments, 0.5 < z ≦ 1.5.

[0102] In some embodiments, 0 < a < 0.24. In some embodiments, 0 < b ≦ 2. Also, in some embodiments, 0 < c ≦ 1.5.

[0103] In some embodiments, 0 ≦ d ≦ 1. In other embodiments, 0 ≦ d ≦ 0.5. Also, in some embodiments, 0 ≦ d ≦ 0.1.

[0104] In some embodiments, D1 is Al or Ga. For example, D1 may be Al. In other embodiments, D1 is Ga.

[0105] In some embodiments, D2 is Ca, Sr, Ba, or any combination thereof. For example, D2 may be Ca. In other embodiments, D2 is Sr. Also, in some embodiments, D2 is Ba.

[0106] In some embodiments, D3 is Ta, Nb, W, Ti, and Mo, or any combination thereof. For example, D3 may be Ta. In some embodiments, D3 is Nb. In other embodiments, D3 is W. In some embodiments, D3 is Ti. Also, in some embodiments, D3 is Mo.

[0107] In some embodiments, D4 is F, Cl, or any combination thereof. For example, D4 may be F. In other embodiments, D4 may be Cl.

[0108] In some embodiments, 0 < a ≤ 0.25. In some embodiments, 0 < b ≤ 0.5. In some embodiments, 0 < c ≤ 1.0. Also, in some embodiments, 0 ≤ d ≤ 0.25.

[0109] In some embodiments, 0 ≤ x ≤ 1.0. In some embodiments, 0 ≤ y ≤ 0.5. In some embodiments, 0 ≤ z ≤ 1.0. Also, in some embodiments, 0 ≤ w ≤ 0.25.

[0110] In some embodiments, 7 - x = 7 - a(vD1) + b(3 - vD2) + c(4 - vD4) - d / 2, where vD1 is the oxidation state of D1, vD2 is the oxidation state of D2, vD3 is the oxidation state of D3, D4 is F, Cl, Br, I, or any combination thereof, y = b, z = c, and w = d. In some embodiments, 0 ≤ x ≤ 1.0.

[0111] In some embodiments of the composition of Chemical Formula (II), D1 is Al, Ga, or any combination thereof, 0 < a ≤ 0.15, D2 is Ca, Sr, Ba, or any combination thereof, 0 < b ≤ 0.5, D3 is Ta, Nb, W, Ti, Mo, or any combination thereof, 0 < c ≤ 1.0, D4 is F, Cl, or any combination thereof, 0 ≤ d ≤ 0.25, 0 ≤ x ≤ 1.0, 0 ≤ y ≤ 0.5, 0 ≤ z ≤ 1.0, and 0 ≤ w ≤ 0.25.

[0112] Equivalent substitution occurs when the dopant has the same charge as the element being substituted, while heterovalence substitution occurs when the dopant has a different charge than the element being substituted. In some embodiments, doping can be heterovalence or equivalent. In some embodiments, a combination of heterovalence and equivalent substitution may exist in the garnet composition. For example, in equivalent substitution, Y 3+ La 3+ Replace with, or H + Li + It can be substituted. In contrast, Ca 2+ is La 3+ It is possible to substitute for one element, and this is a heterovalence substitution. Heterovalence substitution can introduce cation or anion vacancies into the crystal structure. Using heterovalence and equivalent doping, the number of vacancies in the crystal structure and the stoichiometric amounts of other elements in the LLZO composition can be strategically controlled.

[0113] In some embodiments, the solid electrolyte material includes the compositions listed in Table 1.

[0114] [Table 1]

[0115] In some embodiments, the solid electrolyte material is of chemical formula (III) including , Li 7-3x-y+z B x La 3-y C y Zr 2-z D z O 12-a G 2a / n ...(III) During the ceremony, B is any trivalent cation (for example, Al 3+ Or Ga 3+ ), or any combination thereof (in some embodiments, the charge can be compensated by removing three Li for one trivalent B), C is any divalent cation (e.g., Mg 2+) or any combination thereof, and D is any pentavalent cation (e.g., Nb 5+ ) or any combination thereof, G is any monovalent anion (e.g., F - ), divalent anion (e.g., S 2- ), or trivalent anion (e.g., N 3- ), or G is absent n is the charge of the dopant, 0 < x ≤ 0.5, 0 < y ≤ 3, 0 < z ≤ 2, and 0 ≤ a ≤ 12, In some embodiments, 0 < x < 0.24.

[0116] In other embodiments, 0.1 < y ≤ 1.5. In some embodiments, 0.2 < z ≤ 1. Also, in some embodiments, 0 ≤ a ≤ 0.5.

[0117] In some embodiments, B is Al, Ga, H, Fe, Zn, or any combination thereof. For example, B may be Al. In other embodiments, B is Ga. In some embodiments, B is H. In some embodiments, B is Fe. Also, in some embodiments, B is Zn.

[0118] In some embodiments, D2 is Ca, Mg, Sr, Na, Ce, or any combination thereof. For example, D2 may be Ca. In other embodiments, C is Mg. In some embodiments, C is Sr. In some embodiments, C is Ba. In other embodiments, C is Na. Also, in some embodiments, C is Ce.

[0119] In some embodiments, D is Ta, Y, Mo, Sb, Nb, W, Ge, Ti, or any combination thereof. For example, D is Ta. In other embodiments, D is Y. In some embodiments, D is Mo. In some embodiments, D is Sb. In some embodiments, D is Nb. In other embodiments, D is W. In some embodiments, D is Ge. Also, in some embodiments, D is Ti.

[0120] In some embodiments, G is F, Cl, or any combination thereof, or G is absent. For example, G may be F. In other embodiments, G is Cl. Also, in some embodiments, G is absent.

[0121] In some embodiments of formula (III), B is Al, Ga, H, Fe, Zn, or any combination thereof, 0 < x < 0.24, C is Ca, Mg, Sr, Ba, Na, Ce, or any combination thereof, 0.1 < y ≤ 1.5, D is Ta, Y, Mo, Sb, Nb, W, Ge, Ti, or any combination thereof, 0.2 < z ≤ 1, and G is F, Cl, or any combination thereof, 0 ≤ a ≤ 0.5, or G is absent.

[0122] In some embodiments, the solid electrolyte material has the chemical formula (IV) including , Li n B x vB La 3-y C y vC Zr <00​​​​​​​​​​​​​vB is the oxidation state of dopant B, vC is the oxidation state of dopant C, vD is the oxidation state of dopant D (in this formula, any changes are vacancies and the charge is balanced by the lithium amount in the formula, but note that a similar approach can also be used by balancing the oxygen amount in the formula), B is H + , Al 3+ , Ga 3+ , Fe 3+ , Zn 2+ , Ge 4+ , or any combination thereof, C is Ca 2+ , Ba 2+ , Sr 2+ , Mg 2+ , Rb + , Ce 4+ , or any combination thereof, D is Ta 5+ , Y 3+ , Mo 6+ , Nb 5+ , W 6+ , Ge 4+ , Ti 4+ , or any combination thereof, G is F - , Cl - , Br - , I - , or any combination thereof, 0 < x < 0.24, 0 < y ≤ 1.0, 0 < z ≤ 1.0, and 0 ≤ a ≤ 1.0.

[0123] For each of the cations listed for B, C, and D, where applicable, different oxidation states of the cation may be used to vary the balance of lithium or oxygen within the system and to control, if necessary, the final properties of the solid electrolyte. Further, if combinations of cations are doped at any particular site in the same or different oxidation states, Chemical Formula (IV) may be used with the addition of terms identical to those for the formula for n. For example, if dopants for Li sites B1 and B2 are desired, the formula for n is n = 7 - x1(vB1) - x2(vB2) + y(3 - vC) + z(4 - vD) - a / 2. Similar modifications can be made for multiple C dopants, D dopants, or G dopants, or combinations thereof.

[0124] In some embodiments, B is Al 3+ and in some embodiments, the counterion is Ca 2+ In some embodiments, D is Ta 5+ Nb 5+ Ti 4+ or any combination thereof. For example, D may be Nb 5+ In some embodiments, D is Ti 4+ In some embodiments, D is Ta 5+

[0125] In some embodiments, 0 < x < 0.15. In other embodiments, 0.02 < x < 0.10.

[0126] In some embodiments, 0 < y < 0.50. In other embodiments, 0.1 < y < 0.30. In some embodiments, 0.15 < y < 0.28.

[0127] In some embodiments, 0 < z < 0.70. In other embodiments, 0.3 < z < 0.6. In some embodiments, 0.4 < z < 0.55.

[0128] ​In some embodiments, 0 ≦ a < 0.1. In other embodiments, 0 ≦ a < 0.05. Also, in some embodiments, x, y, z, and a are selected such that 6 ≦ n ≦ 7.

[0129] It should be understood that Chemical Formulas (III) and (IV) can be used as guidance in selecting the compositions of Chemical Formulas (I) and (II), particularly with respect to the composition of specific elements compared to other elements. The relative composition is useful for producing a single-phase garnet solid electrolyte material.

[0130] In some embodiments, the solid electrolyte material has the chemical formula (V) including , Li 7-x B a La 3-y C b Zr 2-z D c O 12 ···(V) wherein B is Al or Ga, C is Ca, Sr, Ba, or Mg, D is Ta, Nb, W, Mo, or Ti, -0.5 < x ≦ 1, 0 < a < 0.24, 0 < y ≦ 0.5, 0 < b ≦ 0.5, 0 < z ≦ 1, and 0 < c ≦ 1.

[0131] In some embodiments, B is Al. In other embodiments, B is Ga.

[0132] In some embodiments, C is Ca. In other embodiments, C is Sr. In some embodiments, C is Ba. Also, in some embodiments, C is Mg.

[0133] In some embodiments, D is Ta. In other embodiments, D is Nb. In some embodiments, D is W. In some embodiments, D is Mo. Also, in some embodiments, D is Ti.

[0134] In some embodiments, 0.2 ≦ x ≦ 0.8. In other embodiments,

[0135] For example, in some embodiments of the composition according to Chemical Formula (V), 0.2 ≦ x ≦ 0.8, 0 < a ≦ 0.15, 0 < y ≦ 0.3, 0 < b ≦ 0.3, 0 < z ≦ 1, and 0 < c ≦ 1.

[0136] In some embodiments, the solid electrolyte material comprises the composition described in Table 2.

[0137]

Table 2

[0138] In other embodiments, the solid electrolyte material is a composition of Chemical Formula (VI) including , Li 7+y-z La 3-y Ca y Zr 2-z Ta z O 12 ···(VI) Wherein, 0 < y < 0.3, and 0.2 < z < 0.6.

[0139] For example, in some embodiments of the composition according to Chemical Formula (VI), 0.1 < y < 0.3, and 0.2 < z < 0.6.

[0140] In some embodiments, the solid electrolyte material is a composition of Chemical Formula (VII) including , Li 7- 3x+y-z Al x La 3-y Ca y Zr 2-z Ta z O 12 ···(VII) Wherein, 0 < x < 0.15, 0 < y < 0.3, and 0.2 < z < 0.6.

[0141] For example, in some embodiments of the composition according to Chemical Formula (VII), 0.1 < y < 0.3, and 0.2 < z < 0.6.

[0142] In some embodiments, the solid electrolyte material is a composition of Chemical Formula (VIII) including , Li 7- 3x+y-z B x La 3-y Ca y Zr 2-z Ta z O 12 ···(VIII) Wherein, B is Al, 0 ≤ x < 0.25, 0 < y ≤ 0.5, and 0 < z ≤ 1.

[0143] In some embodiments, 0 ≤ x < 0.15. In other embodiments, x is 0. Also, in some embodiments, x is 0 < x < 0.25. Also, in some embodiments, 0 < x < 0.15.

[0144] In some embodiments, 0 < y < 0.5. In other embodiments, 0 < y < 0.3.

[0145] In some embodiments, 0 < z < 1. In other embodiments, 0.2 < z < 0.6.

[0146] Unless otherwise specified, each subscript in any chemical formula shown in this specification means up to one-hundredth digit, and the range of subscripts includes each one-hundredth value between the upper and lower limits of that range. For example, the range 0 < x < 1 includes 0.01, 0.02, ~0.98, and 0.99.

[0147] Unless otherwise specified, any component of any chemical formula described in this specification (e.g., D1, D2, D3, D4, B, C, D, and / or G) that is a combination of different elements (e.g., Li, Na, and / or K), a combination of different types of cations (Li + , Na + , or K + ), or a combination of different types of anions (e.g., Cl - , Br - , and I - ), the subscript (e.g., a, b, c, and / or d) immediately following such a component represents the total pfu of all elements, cation types, or anion types in that combination. Also, any component of any chemical formula described in this specification (e.g., D1, D2, D3, D4, B, C, D, and / or G) that is a single element (e.g., Li, Na, or K), a single type of cation (Li + , Na + , or K + ), or a single type of anion (e.g., Cl - , Br - , or I - ), the subscript (e.g., a, b, c, and / or d) immediately following such a component represents the total pfu of such an element, cation type, or anion type.

[0148] In some embodiments, the solid electrolyte material is sintered. In some embodiments, the sintered electrolyte material is incorporated into a ceramic separator. In some embodiments, the sintered electrolyte material is incorporated into a host structure for lithium metal plating and stripping. In some embodiments, the sintered electrolyte material is in physical contact with the cathode material and anode material to form an electrode pair and separator layer combination.

[0149] Another aspect of the present invention provides an electrode for a solid-state battery. The electrode comprises a solid electrolyte material. The solid electrolyte material comprises compositions of chemical formulas (I), (II), (III), (IV), (V), (VI), (VII), and / or (VIII).

[0150] Another aspect of the present invention provides a two-layer solid electrolyte structure. The two-layer solid electrolyte structure comprises a porous layer and a high-density layer. At least one of the porous layer and the high-density layer is a material of chemical formula (I), (II), (III), (IV), (V), (VI), (VII), and / or (VIII) comprising the composition of Contains solid electrolyte material.

[0151] Another aspect of the present invention provides a three-layer solid electrolyte structure. The three-layer solid electrolyte structure comprises a first porous layer, a high-density layer, and a second porous layer. At least one of the first porous layer, the high-density layer, and the second porous layer is a material of chemical formula (I), (II), (III), (IV), (V), (VI), (VII), and / or (VIII) comprising the composition of It includes a solid electrolyte material. In some embodiments, the high-density layer is placed between the first porous layer and the second porous layer.

[0152] Another aspect of the present invention provides a solid-state battery comprising a solid electrolyte material, an electrode, a two-layer solid electrolyte structure, or a three-layer solid electrolyte structure as described herein.

[0153] III. Method for forming an unsintered body In another embodiment, the present invention provides a method for forming an unsintered body. This method, (a) Reacting a precursor mixture to form a solid electrolyte material as described herein, (b) Dispersing a solid electrolyte material in a solvent to form a dispersed material, (c) Mixing the first portion of the dispersed material with the first binder and the first plasticizer to form a high-density mixture, (d) Mixing the second portion of the dispersed material with a second binder, a second plasticizer, and a pore-forming agent to form a porous mixture, (e) Casting a high-density mixture onto a first substrate to form a high-density cast tape, (f) Casting a porous mixture onto a second substrate to form a porous cast tape, (g) Drying the high-density cast tape and porous cast tape, (h) Laminating a high-density cast tape with a porous cast tape to form an unsintered body, which is a part of the process.

[0154] In some embodiments, the method includes adding a lithium-donating compound to at least one of a dispersion material, a high-density mixture, and a porous mixture. For example, the method may include adding a lithium-donating compound to a dispersion material. In other embodiments, the method may include adding a lithium-donating compound to a high-density mixture. And in some embodiments, the method may include adding a lithium-donating compound to a porous mixture.

[0155] In some embodiments, step (a) of the reaction includes calcining the precursor mixture. For example, calcination may be carried out in a heated crucible. In some embodiments, the crucible contains less than about 5 wt% Al2O3.

[0156] In some embodiments, firing is performed at a temperature of approximately 600°C to 1,200°C. In some embodiments, firing is performed at a temperature of approximately 700°C to 1,100°C. In some embodiments, firing is performed at a temperature of approximately 800°C to 1,000°C. In some embodiments, firing is performed at a temperature of approximately 900°C.

[0157] In some embodiments, firing is performed for at least about 1 minute (e.g., about 1 minute to about 60 minutes, about 5 minutes to about 45 minutes, about 10 minutes to about 45 minutes, about 15 minutes to about 30 minutes, about 3 minutes to about 10 minutes, or about 5 minutes to about 15 minutes). In other embodiments, firing is performed for at least about 1 hour (e.g., about 1 hour to about 5 hours, about 1.5 hours to about 4.5 hours, about 2 hours to about 4 hours, or about 2.5 hours to about 3.5 hours). In some embodiments, firing is performed for at least about 5 hours (e.g., about 5 hours to about 12 hours, about 6 hours to about 10 hours, or about 6 hours to about 8 hours). In some embodiments, firing takes place over a period of about 10 to about 14 hours.

[0158] In some embodiments, step (a) of reacting is (a-1) Reacting a precursor mixture to form a solid electrolyte material, (a-2) The solid electrolyte material is pulverized to improve uniformity and reduce particle size.

[0159] In some embodiments, the grinding step (a-2) is performed before dispersing the solid electrolyte material (i.e., step (b)).

[0160] In some embodiments, the method further includes degassing at least one of the high-density mixture and the porous mixture under vacuum. For example, in some embodiments, the high-density mixture is degassed under vacuum. In other embodiments, the porous mixture is degassed under vacuum. Also, in some embodiments, both the high-density mixture and the porous mixture are degassed under vacuum.

[0161] In some embodiments, the drying step (g) is performed at a temperature of about 20°C to about 100°C. In some embodiments, the firing is performed at a temperature of about 40°C to about 80°C. In some embodiments, the drying step (g) is performed at a temperature of about 50°C to about 70°C.

[0162] In some embodiments, the stacking step (h) is: (h-1) Stacking porous cast tape and high-density cast tape, (h-2) Including passing the stacked tapes through a heated roller press.

[0163] In some embodiments, the stacking step (h-1) may include stacking porous cast tape on high-density cast tape. In other embodiments, the stacking step (h-1) includes stacking high-density cast tape on porous cast tape. In some embodiments, the method also includes repeating the lamination step (h) to form a multilayer unfired body.

[0164] In some embodiments, the heated roller press is heated to a temperature of approximately 50°C to approximately 500°C. In other embodiments, the heated roller press is heated to a temperature of approximately 100°C to approximately 300°C. In some embodiments, the heated roller press is heated to a temperature of approximately 150°C to approximately 250°C.

[0165] Another aspect of the present invention provides a method for forming a sintered solid electrolyte. The method comprises forming an unsintered body according to any of the methods described herein. The method also comprises sintering the unsintered body to form a sintered solid electrolyte.

[0166] In some embodiments, the sintering step is carried out at a temperature of about 1,200 °C or lower. For example, the sintering step can be carried out at a temperature of about 900 °C to about 1,200 °C. In some embodiments, the sintering step is carried out for about 1 minute to about 10 hours (e.g., about 1 minute to about 1 hour, about 3 minutes to about 15 minutes, about 5 minutes to about 30 minutes, about 30 minutes to about 60 minutes, about 1 hour to about 3 hours, or about 2 hours to about 4 hours). For example, the sintering step can be carried out over about 1 minute to about 6 hours.

Examples

[0167] IV. Examples To better understand the invention described herein, the following examples are presented. The examples described in this application are provided to illustrate the methods and solid electrolyte materials provided herein and should in no way be construed as limiting their scope.

[0168] Solid electrolyte materials Example 1: Solid electrolyte material of chemical formula (VI) Mixed raw material powders were prepared in the desired stoichiometric ratio to reach a multi-doped lithium lanthanum zirconium oxide (LLZO) of chemical formula Li 7+y-z La 3-y Ca y Zr 2- z Ta z O 12 , wherein 0.1 < y < 0.3 and 0.2 < z < 0.6 (i.e., chemical formula (VI)). The precursor materials for this exemplary embodiment include lithium hydroxide monohydrate (98%, Alfa Aesar), lanthanum oxide (GFS Chemicals, 99.9%), zirconium (IV) oxide (Inframat Advanced Materials, 99.9%), calcium carbonate (Sigma Aldrich, 99.0%), and tantalum (V) oxide (MPIL, 99.9%). Ca 2+ was used to dope the La site and Ta 5+ was used to dope the Zr site.

[0169] Garnet powder was formed by calcining the mixed raw material powder in a crucible at 900°C for approximately 12 hours (h). In this example, the crucible was composed of less than 5 wt% Al2O3 to prevent aluminum migration. A crucible composed of MgO and / or Pt is a suitable example of such a crucible. The garnet powder was then ground in isopropanol to obtain a uniform and small particle size, followed by drying at 55°C to remove the isopropanol. The resulting prepared garnet powder was then mixed with isopropanol and toluene as solvents, and Z3 menhedene fish oil as a dispersant, and ground overnight using milling media to create a dispersion. It will be understood that other grinding and dispersion methods may be used. Polyvinyl butyral (i.e., binder) and benzyl butyl phthalate (i.e., plasticizer) were then added to the dispersion while mixing, and the dispersion was degassed by mixing under vacuum. Next, the degassed dispersion was cast onto a biaxially oriented polyethylene terephthalate film (e.g., Mylar® film) using a doctor blade to form a cast tape (i.e., "high-density tape"). The cast tape was dried at 55°C to form an unsintered solid electrolyte material. Another tape (i.e., "porous tape") was also molded in a similar manner, except that a pore-forming agent was mixed during the addition of the binder and plasticizer. By stacking the tapes and passing them through a roller press heated to 200°F (i.e., approximately 93.3°C), the porous tape was laminated with the high-density tape to form a porous-high-density bilayer laminate. It will be understood that multiple high-density tapes and porous tapes can be laminated at once or in succession to produce multilayer laminates. The resulting bilayer laminate was placed in a tubular furnace with a non-alumina surface, without the master powder, to avoid the migration of aluminum to the product. Next, the bilayer laminate was sintered at 900°C to 1200°C for 1 minute to 6 hours to form a sintered solid electrolyte material.

[0170] Example 2: Solid electrolyte material of chemical formula (VII) Chemical formula Li 7-3x+y-z Al x La 3-y Cay Zr 2-z Ta z O 12 and, in the formula, 0 < x < 0.15, 0.1 < y < 0.3, and 0.2 < z < 0.6 (that is, the chemical formula (VII) described in this specification) composition including A solid electrolyte material was also prepared. The precursor materials for this exemplary embodiment included lithium hydroxide monohydrate (98%, Alfa Aesar), lanthanum oxide (GFS Chemicals, 99.9%), zirconium(IV) oxide (Inframat Advanced Materials, 99.9%), calcium carbonate (Sigma Aldrich, 99.0%), and tantalum(V) oxide (MPIL, 99.9%). Similar to the composition of Example 1, Ca 2+ was used to dope the La site, and Ta 5+ was used to dope the Zr site. Further, Al 3+ was used to dope the Li site. The composition of chemical formula (VII) and the obtained sintered solid electrolyte material were prepared in a substantially similar manner to the composition of chemical formula (VI) and its sintered solid electrolyte material in Example 1, except that Al 3+ (that is, aluminum oxide) was introduced into the mixed powder before firing.

[0171] Analysis of Solid Electrolyte Materials Any solid electrolyte material discussed in these examples other than those already described herein in Examples 1 and 2 was prepared in a substantially similar manner to the composition of chemical formula (VI) and its sintered solid electrolyte material shown in Example 1, except for the components used to form the underlying mixed raw material powder.

[0172] The sintered solid electrolyte material was tested by a destructive test by manually bending it using a "4-point" bending configuration, followed by microscopic evaluation using a scanning electron microscope-backscattered electron detector (SEM-BSD) of the fracture site and surface as evidence of porosity and secondary phases. It will be understood that a 3-point bending configuration can also be used.

[0173] Figures 1A-C show sintered multi-doped LLZO (i.e., Li) with Al doping exceeding approximately 0.15 pfu. 6.55 Al 0.15 La3Zr2O 12 Figure 1A shows a cross-section 101 of the sintered multidoped LLZO. Figure 1B shows the LLZO surface 103 exposed during sintering. Figure 1C shows elemental mapping of Al using SEM-energy-dispersive X-ray spectroscopy (EDS), showing the same region of enriched Al 105 as shown in Figure 1B. In each of these cases, lithium dendrites are shown to propagate along the Al-rich regions at the grain boundaries. Furthermore, the non-uniformity of the crystal grain size in the cross-section shown in Figure 1C indicates abnormal crystal grain growth, which may be due to excessive incorporation of sintering aids. As a result, a prominent secondary phase is formed at the grain boundaries, which is electrochemically reactive and can cause dendrite propagation. Furthermore, these microstructures are mechanically weak. Therefore, it is desirable to control the aluminum content to less than approximately 0.24 pfu, or less than approximately 0.15 pfu and greater than 0.0 pfu.

[0174] In many cases, Al is introduced into the LLZO material during firing or sintering by using a crucible rich in Al2O3, which is reactive with LLZO. When a very high-purity Al2O3 crucible is used during firing, for example, up to about 0.24 pfu or more of Al can be added to the LLZO. The amount of Al cannot be precisely controlled in this type of process. Instead, in some embodiments, the addition of a controlled amount of Al may be achieved by firing and / or sintering on a substrate containing less than about 5% Al2O3 using a desired amount of Al-containing precursor material before firing.

[0175] Figures 2A and 2B show the effect of less than approximately 0.15 pfu of Al on the microstructure of Al-containing and Al-free sintered multi-doped LLZO. In Figure 2A, an LLZO bilayer was sintered without Al doping. A cross-section of the high-density layer 201 beneath the porous layer 203 can be seen in Figure 2A as having a granular, low-density structure after sintering. In contrast, Figure 2B shows a cross-section of the Al-doped LLZO high-density layer 205 beneath the porous layer 207, where the density is improved with significantly less granular formation. The presence of less than approximately 0.15 pfu of Al (e.g., less than approximately 0.12 pfu, less than approximately 0.10 pfu, or approximately 0.01 pfu to approximately 0.08 pfu) significantly improves density and reduces porosity of the sintered LLZO without forming an unstable secondary phase. In the solid electrolyte in Figure 2B, aluminum is present in an amount of 0.05 pfu.

[0176] Figure 3 shows a SEM-BSD cross-section of a sintered multi-doped LLZO having a two-layer structure of a porous layer 301 and a high-density layer 303, where the LLZO is doped with less than approximately 0.1 pfu of Al, less than approximately 0.3 pfu and more than approximately 0.1 pfu of Ca, and more than approximately 0.4 pfu and less than approximately 0.6 pfu of Ta. Advantageously, the sintered multi-doped LLZO in Figure 3 was prepared without the use of a powder bed.

[0177] Figures 4A and 4B are cross-sectional images of the sintered multi-doped LLZO of Examples 1 and 2. Both sintered multi-doped LLZO materials were prepared without the use of a powder bed. Figure 4A shows the sintered multi-doped LLZO of Example 1, which has a porous layer 401 and a high-density layer 403. As can be seen from the figure, the high-density layer 403 is remarkably porous. Importantly, if lithium is lost during sintering, resulting in lithium deficiencies in the LLZO composition, the LLZO cannot be properly sintered and densified. Lithium deficiencies can occur when the amount of lithium present is less than the stoichiometric amount, and / or when lithium loss prevents the formation of a stable cubic phase during firing and / or sintering. Generally, a loss of more than about 1% of lithium from the initial amount can lead to lithium deficiencies.

[0178] Figure 4B shows the sintered multi-doped LLZO of Example 2, having a porous layer 405 and a high-density layer 407. As can be seen from the figure, the high-density layer 407 has very low porosity and was completely sintered without the use of a powder bed. The ability to effectively sinter without the use of a powder bed demonstrates the potential advantages of the solid electrolyte materials described herein.

[0179] Conductivity of solid electrolyte materials The sintered solid electrolyte materials of Examples 1 and 2 were tested for conductivity. Au electrodes were sputtered onto both sides of each sintered solid electrolyte material. Ag wire contacts were bonded using Ag paste. The impedance response of the sintered solid electrolyte materials was analyzed over a frequency range of 1 MHz to 100 Hz using electrochemical impedance spectroscopy to determine the ionic conductivity. The ionic conductivity of the sintered solid electrolyte of Example 1 was measured to be 2.2 mS / cm. The sintered solid electrolyte material of Example 2 showed an ionic conductivity of 4.2 mS / cm.

[0180] X-ray diffraction analysis Compositions such as those described herein can be evaluated for quality after mixing and calcination by, for example, inductively coupled plasma, X-ray diffraction (XRD), and ignition loss. Preferably, the powder obtained after calcination has a uniform composition, possesses the desired crystalline phase purity determined by XRD, contains only a small amount of unreacted residual components such as hydroxides and carbonates (evaluated by measuring ignition loss), and has the desired elemental composition determined by inductively coupled plasma.

[0181] Figure 5 shows the reference XRD spectra of cubic LLZO507 and tetragonal LLZ505, as well as the measurement results for as-fired multi-doped LLZO503 (i.e., the firing composition of Example 2) and as-fired undoped LLZ501. The multi-doped and undoped LLZO were mixed and fired as described above. As shown in Figure 5, the multi-doped LLZO503 is high Li +The conductivity of LLZO501 closely matches that of the cubic phase 507, but the undoped LLZO501 matches that of the low-conductivity tetragonal phase 505.

[0182] battery cell In some embodiments of this approach, the sintered electrolyte may be incorporated into the battery cell as a ceramic separator, or as a host structure for lithium metal plating, or both. The sintered electrolyte is in physical contact with the cathode material and anode material to form the electrode pair and separator layer combination of the battery. These layers may optionally be stacked with an anode current collector in contact with the anode surface opposite the solid electrolyte separator and a cathode current collector in contact with the anode surface opposite the solid electrolyte separator to form a cell. This battery cell can be incorporated into a wide variety of applications, including but not limited to electric vehicles.

[0183] A battery cell containing a multi-doped LLZO ceramic bilayer separator according to Example 2 was fabricated using an anode (lithium metal) and a cathode (lithium nickel manganese cobalt oxide (NMC)). Figure 6 shows the voltage profile of the battery cell as a function of capacity when the cell is charged and discharged at C / 20 (1st cycle), C / 10 (2nd to 3rd cycles), and C / 5 (4th to 7th cycles). The high Coulomb efficiency is evident from the very similar charge and discharge capacities in each cycle, indicating high cell performance.

[0184] Equivalents and range In the claims, articles such as “a,” “an,” and “the” may mean one or more unless otherwise indicated or made clear from the context. Claims or descriptions that include “or” between one or more elements of a group are considered satisfied unless otherwise indicated or made clear from the context if one, two or more, or all of the elements of the group are present, used, or otherwise related to a given product or process. The present invention includes embodiments in which exactly one element of the group is present, used, or otherwise related to a given product or process. The present invention includes embodiments in which two or more, or all, of the elements of the group are present, used, or otherwise related to a given product or process.

[0185] Furthermore, the present invention encompasses all variations, combinations, and permutations in which one or more limitations, elements, clauses, and descriptive terms from one or more of the enumerated claims are introduced into another claim. For example, any claim dependent on another claim may be modified to include one or more limitations found in any other claim dependent on the same basic claim. Where elements are presented as a list, for example in Markush group form, each subgroup of the elements is also disclosed, and any element(s) may be removed from this group. In general, where the present invention or an aspect of the present invention is referred to as including certain elements and / or features, it should be understood that certain embodiments or aspects of the present invention consist of or are essentially such elements and / or features. For the sake of brevity, those embodiments are not specifically described verbatim in this specification. The terms “including” and “containing” are intended to be open and should also be noted to allow for the inclusion of additional elements or steps. Where a scope is given, it includes the endpoints. Furthermore, unless otherwise indicated or otherwise evident from the context and the understanding of those skilled in the art, values ​​expressed as ranges may be estimated to any specific value or subrange within the defined range of different embodiments of the invention, up to one-tenth of the lower limit unit of the range, unless the context otherwise explicitly indicates.

[0186] This application refers to various issued patents, published patent applications, journal articles, and other publications, all of which are incorporated herein by reference. In the event of any conflict between any of the incorporated references and this specification, this specification shall prevail. Furthermore, any particular embodiment of the Invention within the scope of the prior art may be clearly excluded from any one or more of the claims. Such embodiments may be excluded even if the exclusion is not expressly stated herein, as they are considered to be known to those skilled in the art. Any particular embodiment of the Invention may be excluded from any claim for any reason, whether or not it relates to the existence of the prior art.

[0187] Those skilled in the art will be able to recognize or confirm many equivalents to the specific embodiments described herein using only routine experiments. The scope of the embodiments described herein is not intended to be limited to the above description, but rather as set out in the appended claims. It will be apparent to those skilled in the art that various changes and modifications to this description can be made without departing from the spirit or scope of the invention, as defined in the following claims. The present invention provides, for example, the following items. (Item 1) A solid electrolyte material comprising a composition of chemical formula (I), wherein M1 7-x D1 a M2 3-y D2 b M3 2-z D3 c O 12-w D4 d ···(I) in the formula, M1 is Li, M2 is La, M3 is Zr, D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof, D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof, D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof, D4 is F, Cl, Br, I, S, Se, Te, N, P, or any combination thereof, 0≦w≦2、 -0.5<x≦3、 0≦y≦3、 0≦z≦2、 0≦a≦2、 0≦b≦3、 0 ≦ c ≦ 2, and 0 ≦ d ≦ 2, and at least one of a, b, c, and d is not 0, said solid electrolyte material. (Item 2) 0<y≦3、 0<z≦2、 0<a≦2、 0 < b ≦ 3, and 0 < c ≦ 2, the solid electrolyte material according to Item 1. (Item 3) 0 ≦ w ≦ 1, the solid electrolyte material according to Item 1 or 2. (Item 4) 0 ≦ w ≦ 0.5, the solid electrolyte material according to any one of Items 1 to 3. (Item 5) 0 ≦ w ≦ 0.1, the solid electrolyte material according to any one of Items 1 to 4. (Item 6) 0 ≦ x ≦ 1, the solid electrolyte material according to any one of Items 1 to 5. (Item 7) 0.2 ≦ x ≦ 0.8, the solid electrolyte material according to any one of Items 1 to 6. (Item 8) 0 < y < 3, the solid electrolyte material according to any one of Items 1 to 7. (Item 9) 0 < y < 1, the solid electrolyte material according to any one of Items 1 to 8. (Item 10) 0 < y < 0.5, the solid electrolyte material according to any one of Items 1 to 9. (Item 11) 0.05 ≦ y ≦ 0.25, the solid electrolyte material according to any one of Items 1 to 10. (Item 12) 0 < a ≦ 1, the solid electrolyte material according to any one of Items 1 to 11. (Item 13) The solid electrolyte material according to any one of items 1 to 12, where 0 < a < 0.24. (Item 14) The solid electrolyte material according to any one of items 1 to 13, where 0 < b < 3. (Item 15) The solid electrolyte material according to any one of items 1 to 14, where 0 < b < 1. (Item 16) The solid electrolyte material according to any one of items 1 to 15, where 0 < b < 0.5. (Item 17) The solid electrolyte material according to any one of items 1 to 16, where 0.05 ≤ b ≤ 0.25. (Item 18) The solid electrolyte material according to any one of items 1 to 17, where 0 < c ≤ 0.7. (Item 19) The solid electrolyte material according to any one of items 1 to 18, where 0 < c ≤ 0.5. (Item 20) The solid electrolyte material according to any one of items 1 to 19, where 0.2 ≤ c ≤ 0.5. (Item 21) The solid electrolyte material according to any one of items 1 to 20, where 0 ≤ d ≤ 1. (Item 22) The solid electrolyte material according to any one of items 1 to 21, where 0 ≤ d ≤ 0.5. (Item 23) The solid electrolyte material according to any one of items 1 to 22, where 0 ≤ d ≤ 0.1. (Item 24) The solid electrolyte material according to any one of items 1 to 23, where D1 is Al, Fe, Zn, and Ga, or any combination thereof. (Item 25) The solid electrolyte material according to any one of items 1 to 24, where D2 is Ca, Sr, Ba, Bi, and Nd, or any combination thereof. (Item 26) The solid electrolyte material according to any one of items 1 to 25, where D3 is Ta, Nb, W, Ti, and Mo, or any combination thereof. (Item 27) 7 - x = 7 - a(vD1) + b(3 - vD2) + c(4 - vD4) - d / 2, where vD1 is the oxidation state of D1, vD2 is the oxidation state of D2, vD3 is the oxidation state of D3, D4 is F, Cl, Br, I, or any combination thereof, y = b, z = c, and w = d, for the solid electrolyte material according to item 1. (Item 28) The solid electrolyte material according to item 27, where 0 ≤ x ≤ 1.0. (Item 29) A solid electrolyte material containing the composition of Chemical Formula (II), Li 7-x D1 a La 3-y D2 b Zr 2-z D3 c O 12-w D4 d ···(II) where D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof, D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof, D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Te, I, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof, D4 is F, Cl, Br, I, S, Se, Te, or any combination thereof, 0≦w<2、 -0.5<x≦3、 0<y≦3、 0<z≦2、 0<a≦2、 0 < b ≤ 3, 0 < c ≤ 2, and 0 ≤ d ≤ 2, for the solid electrolyte material. (Item 30) 0 ≤ w ≤ 1 for the solid electrolyte material according to Item 29. (Item 31) 0 ≤ w ≤ 0.5 for the solid electrolyte material according to Item 29 or 30. (Item 32) 0 ≤ w ≤ 0.1 for the solid electrolyte material according to any one of Items 29 to 31. (Item 33) 0 < x ≤ 1.5 for the solid electrolyte material according to any one of Items 29 to 32. (Item 34) 0.5 < y ≤ 2 for the solid electrolyte material according to any one of Items 29 to 33. (Item 35) 0.5 < z ≤ 1.5 for the solid electrolyte material according to any one of Items 29 to 34. (Item 36) 0 < a < 0.24 for the solid electrolyte material according to any one of Items 29 to 35. (Item 37) 0 < b ≤ 2 for the solid electrolyte material according to any one of Items 29 to 36. (Item 38) 0 < c ≤ 1.5 for the solid electrolyte material according to any one of Items 29 to 37. (Item 39) 0 ≤ d ≤ 1 for the solid electrolyte material according to any one of Items 29 to 38. (Item 40) 0 ≤ d ≤ 0.5 for the solid electrolyte material according to any one of Items 29 to 39. (Item 41) 0 ≤ d ≤ 0.1 for the solid electrolyte material according to any one of Items 29 to 40. (Item 42) D1 is Al, Ga, or any combination thereof, D2 is Ca, Sr, Ba, or any combination thereof, 0 < b ≤ 0.5, D3 is Ta, Nb, W, Ti, Mo, or any combination thereof, 0 < c ≤ 1.0, D4 is F, Cl, or any combination thereof, for the solid electrolyte material according to Item 29. (Item 43) The solid electrolyte material according to item 42, where 0 < a ≤ 0.25. (Item 44) The solid electrolyte material according to item 42 or 43, where 0 < b ≤ 0.5. (Item 45) The solid electrolyte material according to any one of items 42 to 44, where 0 < c ≤ 1.0. (Item 46) The solid electrolyte material according to any one of items 42 to 45, where 0 ≤ d ≤ 0.25. (Item 47) The solid electrolyte material according to any one of items 42 to 46, where 0 ≤ x ≤ 1.0. (Item 48) The solid electrolyte material according to any one of items 42 to 47, where 0 ≤ y ≤ 0.5. (Item 49) The solid electrolyte material according to any one of items 42 to 48, where 0 ≤ z ≤ 1.0. (Item 50) The solid electrolyte material according to any one of items 42 to 49, where 0 ≤ w ≤ 0.25. (Item 51) 7 - x = 7 - a(vD1)+b(3 - vD2)+c(4 - vD4)-d / 2, where vD1 is the oxidation state of D1, vD2 is the oxidation state of D2, vD3 is the oxidation state of D3, D4 is F, Cl, Br, I, or any combination thereof, y = b, z = c, and w = d. The solid electrolyte material according to item 29. (Item 52) The solid electrolyte material according to item 51, where 0 ≤ x ≤ 1.0. (Item 53) A solid electrolyte material containing a composition of chemical formula (IV), Li n B x vB La 3-y C y vC Zr 2-z D z vD O 12-a G a ···(IV) where n = 7 - x(vB)+y(3 - vC)+z(4 - vD)-a / 2, where vB is the oxidation state of B, vC is the oxidation state of C, vD is the oxidation state of D, B is H + 、Al3+ , Ga 3+ , Fe 3+ , Zn 2+ , Ge 4+ , or any combination thereof, C is Ca 2+ , Ba 2+ 、Sr 2+ , Mg 2+ , Rb + , Ce 4+ , or any combination thereof, D is Ta 5+ 、Y 3+ , Mo 6+ , Nb 5+ 、W 6+ , Ge 4+ , Ti 4+ , or any combination thereof, G is F - 、Cl - 、Br - 、I - , or any combination thereof, 0<x<0.24、 0<y≦1.0、 0 < z ≤ 1.0, and 0 ≤ a ≤ 1.0. The said solid electrolyte material. (Item 54) The solid electrolyte material according to item 53, where B is Al 3+ . (Item 55) The solid electrolyte material according to item 53 or 54, where C is Ca 2+ . (Item 56) The solid electrolyte material according to any one of items 53 to 55, where D is Ta 5+ , Nb 5+, Ti 4+ , or any combination thereof (Item 57) The solid electrolyte material according to any one of items 53 to 56, where D is Ta 5+ . (Item 58) where 0 < x < 0.15 and at least one of 0 < x < 0.15, 0 < y < 0.50, and 0 < z < 0.70, the solid electrolyte material according to any one of Items 53 to 57. (Item 59) where 0.02 < x < 0.10, the solid electrolyte material according to any one of Items 53 to 58. (Item 60) where 0 < y < 0.50, the solid electrolyte material according to any one of Items 53 to 59. (Item 61) where 0.1 < y < 0.30, the solid electrolyte material according to any one of Items 53 to 60. (Item 62) where 0.15 < y < 0.28, the solid electrolyte material according to any one of Items 53 to 61. (Item 63) where 0 < z < 0.70, the solid electrolyte material according to any one of Items 53 to 62. (Item 64) where 0.3 < z < 0.6, the solid electrolyte material according to any one of Items 53 to 63. (Item 65) where 0.4 < z < 0.55, the solid electrolyte material according to any one of Items 53 to 64. (Item 66) where 0 ≦ a < 0.1, the solid electrolyte material according to any one of Items 53 to 65. (Item 67) where 0 ≦ a < 0.05, the solid electrolyte material according to any one of Items 53 to 66. (Item 68) where x, y, z, and a are selected such that 6 ≦ n ≦ 7, the solid electrolyte material according to Item 53. (Item 69) A solid electrolyte material containing a composition of Chemical Formula (V), Li 7-x B a La 3-y C b Zr 2-z D c O 12 ···(V) where B is Al or Ga, C is Ca, Sr, Ba, or Mg, D is Ta, Nb, W, Mo, or Ti, 0≦x≦1、 0<a<0.24、 0<y≦0.5、 0<b≦0.5、 0 < z ≦ 1, and 0 < c ≦ 1, the solid electrolyte material. (Item 70) A solid electrolyte material containing a composition of Chemical Formula (VI), Li 7+y-z La 3-y Ca y Zr 2-z Ta z O 12 ···(VI) where 0 < y < 0.3, and 0.2 < z < 0.6, the solid electrolyte material. (Item 71) A solid electrolyte material containing a composition of Chemical Formula (VII), Li 7-3x+y-z Al x La 3-y Ca y Zr 2-z Ta z O 12 ···(VII) where 0<x<0.15、 0 < y < 0.3, and 0.2 < z < 0.6, the solid electrolyte material. (Item 72) A solid electrolyte material containing a composition of Chemical Formula (VIII), Li 7-3x+y-z B xLa 3-y Ca y Zr 2-z Ta z O 12 ···(VIII) where B is Al, 0≦x<0.25、 0 < y ≦ 0.5, and 0 < z ≦ 1, the solid electrolyte material. (Item 73) where 0 ≦ x < 0.15, the solid electrolyte material according to Item 72. (Item 74) where x is 0, the solid electrolyte material according to Item 72. (Item 75) The solid electrolyte material according to item 72, where 0 < x < 0.25. (Item 76) The solid electrolyte material according to item 72, where 0 < y < 0.3. (Item 77) The solid electrolyte material according to item 72, where 0.2 < z < 0.6. (Item 78) A two-layer solid electrolyte structure comprising a porous layer, a high-density layer, and at least one of the porous layer and the high-density layer contains the solid electrolyte material according to any one of items 1 to 77. (Item 79) A three-layer solid electrolyte structure comprising a first porous layer, a high-density layer, and a second porous layer, and at least one of the first porous layer, the high-density layer, and the second porous layer contains the solid electrolyte material according to any one of items 1 to 77. (Item 80) The solid electrolyte material according to any one of items 1 to 77, where the solid electrolyte material is sintered. (Item 81) A solid battery comprising the electrolyte material according to any one of items 1 to 77. (Item 82) The solid battery according to item 81, where the electrolyte material is sintered. (Item 83) The solid battery according to item 82, where the sintered electrolyte material is incorporated into a ceramic separator. (Item 84) The solid battery according to item 82, where the sintered electrolyte material is incorporated into a host structure for lithium metal plating and stripping. (Item 85) The solid battery according to item 82, where the sintered electrolyte material physically contacts a cathode material and an anode material to form a combination of an electrode pair and a separator layer. (Item 86) A method for forming a green body, comprising (a) reacting a precursor mixture to form the solid electrolyte material according to any one of items 1 to 77; (b) dispersing the solid electrolyte material in a solvent to form a dispersion material; (c) mixing a first portion of the dispersion material with a first binder and a first plasticizer to form a high-density mixture; ​ ​ ​ ​ (h) The method comprising laminating the porous cast tape onto the high-density cast tape to form an unsintered body. (Item 87) The method according to item 86, further comprising adding a lithium-donating compound to at least one of the dispersion material, the high-density mixture, and the porous mixture. (Item 88) The method according to item 86, wherein step (a) of reacting comprises calcining the precursor mixture. (Item 89) The firing is carried out in a heated crucible, as described in item 88. (Item 90) The reaction step (a) is (a-1) Reacting a precursor mixture to form a solid electrolyte material, (a-2) The method according to item 86, comprising grinding the solid electrolyte material to improve its uniformity and reduce its particle size. (Item 91) The method according to item 86, further comprising degassing at least one of the high-density mixture and the porous mixture under vacuum. (Item 92) The aforementioned stacking step (h) is (h-1) Stacking the porous cast tape and the high-density cast tape, (h-2) The method of item 86, which includes passing a stack of tapes through a heated roller press. (Item 93) The method according to item 86, wherein the lamination step is repeated to form a multilayer unfired body. (Item 94) A method for forming a sintered solid electrolyte, Form an unsintered body according to the method described in any one of items 86 to 93, The method comprising sintering the unsintered body to form the sintered solid electrolyte.

Claims

1. A solid electrolyte material comprising a composition of chemical formula (IV), Li ｎ B ｘ ｖＢ La ３－ｙ 3 ｙ ｖＣ h ２－ｚ D ｚ ｖＤ 9 １２－ａ 7 ａ ・・・(96) During the ceremony, n = 7 - x(vB) + y(3 - vC) + z(4 - vD) - a / 2, where vB is the oxidation state of B, vC is the oxidation state of C, and vD is the oxidation state of D. B is H ＋ Al ３＋ Ga ３＋ Fe ３＋ , Zn ２＋ , Ge ４＋ , or any combination thereof, C is Ca ２＋ , Sr ２＋ Mg ２＋ , Rb ＋ Ce ４＋ , or any combination thereof, D is Ta ５＋ , Y ３＋ Mo ６＋ , W ６＋ , Ge ４＋ Ti ４＋ , or any combination thereof, G is F － , Cl － , Br － , I － , or any combination thereof, 0 < x < 0.24, 0 < y ≤ 1.0, 0 < z ≤ 1.0, and The solid electrolyte material wherein 0 ≤ a ≤ 1.

0.

2. B is Al ３＋ The solid electrolyte material according to claim 1.

3. C is Ca ２＋ The solid electrolyte material according to claim 1.

4. D is Ta ５＋ , Nb ５＋ Ti ４＋ The solid electrolyte material according to claim 1, which is either one of the above or any combination thereof.

5. D is Ta ５＋ The solid electrolyte material according to claim 1.

6. The solid electrolyte material according to claim 1, wherein at least one of 0 < x < 0.15, 0 < y < 0.50, and 0 < z < 0.

70.

7. The solid electrolyte material according to claim 1, wherein 0.02 < x < 0.

10.

8. The solid electrolyte material according to claim 1, wherein 0 < y < 0.

50.

9. The solid electrolyte material according to claim 1, wherein 0.1 < y < 0.

30.

10. The solid electrolyte material according to claim 1, wherein 0.15 < y < 0.

28.

11. The solid electrolyte material according to claim 1, wherein 0 < z < 0.

70.

12. The solid electrolyte material according to claim 1, wherein 0.3 < z < 0.

6.

13. The solid electrolyte material according to claim 1, wherein 0.4 < z < 0.

55.

14. The solid electrolyte material according to claim 1, wherein 0 ≤ a < 0.

1.

15. The solid electrolyte material according to claim 1, wherein 0 ≤ a < 0.

05.

16. The solid electrolyte material according to claim 1, wherein x, y, z, and a are selected such that 6 ≤ n ≤ 7.

17. A solid electrolyte material comprising a composition of chemical formula (V), Li ７－ｘ B ａ La ３－ｙ C ｂ Z ２－ｚ D ｃ O １２ ・・・(V) During the ceremony, B is either Al or Ga, C is Ca, Sr, or Mg. D is Ta, W, Mo, or Ti, 0 ≤ x ≤ 1, 0 < a < 0.24, 0 < y ≤ 0.5, 0 < b ≤ 0.5, 0 < z ≤ 1, and The solid electrolyte material wherein 0 < c ≤ 1.

18. A solid electrolyte material comprising a composition of chemical formula (VII), Li ７－３ｘ＋ｙ－ｚ Al ｘ La ３－ｙ Ca ｙ Z ２－ｚ Ta ｚ O １２ ・・・(VII) During the ceremony, 0 < x < 0.15, 0 < y < 0.3, and The solid electrolyte material wherein 0.2 < z < 0.

6.

19. A solid electrolyte material comprising a composition of chemical formula (VIII), Li ７－３ｘ＋ｙ－ｚ B ｘ La ３－ｙ Ca ｙ Zr ２－ｚ Ta ｚ O １２ ・・・(VIIII) During the ceremony, B is Al, 0 < x < 0.25, 0 < y ≤ 0.5, and The solid electrolyte material wherein 0 < z ≤ 1.

20. The solid electrolyte material according to claim 19, wherein 0 < y < 0.

3.

21. The solid electrolyte material according to claim 19, wherein 0.2 < z < 0.

6.

22. A solid electrolyte material comprising a composition of chemical formula (I), M1 7-x D1 a M2 3-y D2 b M3 2-z D3 c O 12-w D4 d ・・・(I) During the ceremony, M1 is Li, M2 is La, M3 is Zr, D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof. D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof. D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof. D4 is F, Cl, Br, I, S, Se, Te, N, P, or any combination thereof. 0 ≤ w ≤ 2, -0.5 < x ≤ 3, 0 ≤ y ≤ 3, 0 ≤ z ≤ 2, 0 ≤ a ≤ 2, 0 ≤ b ≤ 3, 0 ≤ c ≤ 2, and 0 ≤ d ≤ 2, The solid electrolyte material wherein at least one of a, b, c, and d is not zero.

23. A solid electrolyte material comprising a composition of chemical formula (II), Li 7-x D1 a La 3-y D2 b Zr 2-z D3 c O 12-w D4 d ・・・(II) During the ceremony, D1 is H, Be, B, Al, Fe, Zn, Ga, Ge, or any combination thereof. D2 is Na, K, Ca, Rb, Sr, Y, Ag, Ba, Bi, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Zn, Ce, or any combination thereof. D3 is Mg, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Ge, As, Se, Nb, Mo, Tc, Ru, Rh, Pd, Cd, In, Sn, Sb, Te, I, Hf, Ta, W, Ir, Pt, Au, Hg, Tl, Pb, Ce, Eu, Te, Y, Sr, Ca, Ba, Gd, Ge, or any combination thereof. D4 is F, Cl, Br, I, S, Se, Te, or any combination thereof. 0 ≤ w < 2, -0.5 < x ≤ 3, 0 < y ≤ 3, 0 < z ≤ 2, 0 < a ≤ 2, 0 < b ≤ 3, 0 < c ≤ 2, and The solid electrolyte material wherein 0 ≤ d ≤ 2.

24. A solid electrolyte material comprising a composition of chemical formula (III), Li 7-3x-y+z B x La 3-y C y Zr 2-z D z O 12-a G 2a / n ... (III) During the ceremony, B is any trivalent cation, or any combination thereof. C is any divalent cation, or any combination thereof, and D is any pentavalent cation, or any combination thereof. G is either any monovalent, divalent, or trivalent anion, or G does not exist. n is the charge of the dopant, 0 < x ≤ 0.5, 0 < y ≤ 3, 0 < z ≤ 2, and The solid electrolyte material wherein 0 ≤ a ≤ 12.

25. A solid electrolyte material comprising a composition of chemical formula (VI), Li 7+y-z La 3-y Ca y Zr 2-z Ta z O 12 ・・・(VI) During the ceremony, 0 < y < 0.3, and The solid electrolyte material wherein 0.2 < z < 0.

6.

26. Li 6.40 Al 0.05 La 2.95 Ca 0.05 Zr 1.50 Ta 0.50 O 12 ; Li 6.75 La 2.75 Ca 0.25 Zr 1.50 Ta 0.50 O 12 ; Li 6.30 Ga 0.15 La 2.95 Ba 0.05 Zr 1.70 Nb 0.30 O 12 ; Li 6.85 Al 0.15 La 2.70 Sr 0.30 Zr 1.00 Ti 1.00 O 12 ; Li 6.30 Ga 0.08 La 2.76 Mg 0.24 Zr 1.65 W 0.35 O 12 ; A solid electrolyte material comprising a composition selected from Li 6.60, Al 0.05, La 2.90, Ca 0.10, Zr 1.70, Ta 0.30, O 11.90, F 0.10; or any combination thereof.

27. It has a two-layer solid electrolyte structure, A porous layer, Includes a high-density layer, The two-layer solid electrolyte structure wherein at least one of the porous layer and the high-density layer comprises the solid electrolyte material described in any one of claims 1 to 26.

28. It has a three-layer solid electrolyte structure, A first porous layer, High-density layer and It includes a second porous layer, The three-layer solid electrolyte structure wherein at least one of the first porous layer, the high-density layer, and the second porous layer comprises the solid electrolyte material described in any one of claims 1 to 26.

29. The solid electrolyte material according to any one of claims 1 to 26, wherein the solid electrolyte material is sintered.

30. A solid battery comprising the electrolyte material according to any one of claims 1 to 26.

31. The solid battery according to claim 30, wherein the electrolyte material is sintered.

32. The solid battery according to claim 31, wherein the sintered electrolyte material is incorporated into a ceramic separator.

33. The solid battery according to claim 31, wherein the sintered electrolyte material is incorporated into a host structure for lithium metal plating and stripping.

34. The solid battery according to claim 31, wherein the sintered electrolyte material is in physical contact with the cathode material and the anode material to form an electrode pair and a separator layer combination.

35. A method for forming an unsintered body, (a) Reacting a precursor mixture to form a solid electrolyte material according to any one of claims 1 to 26, (b) Dispersing the solid electrolyte material in a solvent to form a dispersed material, (c) Mixing the first portion of the dispersion material with the first binder and the first plasticizer to form a high-density mixture, (d) Mixing the second portion of the dispersion material with a second binder, a second plasticizer, and a pore-forming agent to form a porous mixture, (e) Casting the high-density mixture onto a first substrate to form a high-density cast tape, (f) Casting the porous mixture onto a second substrate to form a porous cast tape, (g) Drying the high-density cast tape and the porous cast tape, (h) The method comprising laminating the porous cast tape onto the high-density cast tape to form the unsintered body.

36. The method according to claim 35, further comprising adding a lithium-donating compound to at least one of the dispersion material, the high-density mixture, and the porous mixture.

37. The method according to claim 35, wherein the reaction step (a) includes calcining the precursor mixture.

38. The method according to claim 37, wherein the firing is carried out in a heated crucible.

39. The reaction step (a) is (a-1) Reacting a precursor mixture to form a solid electrolyte material, (a-2) The method according to claim 35, further comprising pulverizing the solid electrolyte material to improve its uniformity and reduce its particle size.

40. The method according to claim 35, further comprising degassing at least one of the high-density mixture and the porous mixture under vacuum.

41. The aforementioned stacking step (h) is (h-1) Stacking the porous cast tape and the high-density cast tape, (h-2) The method according to claim 35, comprising passing the stacked tapes through a heated roller press.

42. The method according to claim 35, wherein the lamination step is repeated to form a multilayer unfired body.

43. A method for forming a sintered solid electrolyte, Forming an unsintered body according to the method of claim 35, The method comprising sintering the unsintered body to form the sintered solid electrolyte.

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