Solid electrolyte material and solid-state battery made therefrom

Abstract

A solid electrolyte material is provided that includes Li, T, X, and A, where T is at least one of P, As, Si, Ge, Al, and B; X is BH4; and A is S, Se, or N. The solid electrolyte material can include glass-ceramics and / or mixed crystalline phases, and exhibits high ionic conductivity and compatibility with high voltage cathodes and lithium metal anodes.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Application No. 62 / 993,571, filed March 23, 2020, and U.S. Provisional Application No. 63 / 088,233, filed October 6, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The various embodiments described herein relate to the fields of solid-state primary and secondary electrochemical cells, electrodes and electrode materials, electrolytes and electrolyte compositions, and corresponding methods of manufacturing and using the same. Background Technology

[0004] The increasing number and diversity of mobile devices, the development of hybrid / electric vehicles, and the growth of IoT devices are driving greater demand for battery technologies with improved reliability, capacity (Ah), thermal characteristics, lifespan, and rechargeability. Currently, while lithium solid-state battery technology offers potential improvements in safety and packaging efficiency and allows for new high-energy chemistry materials, further improvements are needed. Specifically, work is underway to improve the production and performance characteristics of solid electrolyte compositions.

[0005] The most widely studied and adopted inorganic solid-state ionic conductors are the so-called "lithium-silver-germanium ore". These materials are derived from the natural mineral lithium-silver-germanium ore with the composition Ag8GeS6, which was first reported in 1886 (Winkler, C. (1886) Germanium GE, a novel nonmetallic element (Germanium GE, ein nues, nichtmetallisches Element). German Journal of Chemistry (Ber. Dtsch. Chem. Ges.) 19:201-211). When summarizing the composition of such materials, U.S. Patent No. 8,075,865 provides the formula Li + (12-n-y) T n+ A 2- (6-y) X - (y) Argyrodite is defined as a "lithium-argyrodite" containing mobile lithium ions and used as a solid electrolyte. Typically, argyrodite exhibits a cubic structure with space group F-43m; however, the native mineral argyrodite takes on an orthorhombic structure with space group Pna21. Generally, the terms "argyrodite-type" or "argyrodite-like" refer to crystalline materials conforming to the above formula, rather than any specific crystal structure.

[0006] It has been confirmed that the lithium-ion conductivity of sulfide-germanium ore-type materials is related to that of Li... + (12-n-y) T n+ A 2- (6-y) X - (y) The amount of component “X” is related to the assumption that “T” = P, “A” = S, and “X” = Cl, a common composition of a “lithium argyrodite”. Adeli et al. (Adeli, P.; Bazak, JD.; Park, KH.; Kochetkov, L.; Huq, A.; Goward, GR.; Nazar, LF., Agnew. Chem. Int. Ed. (2019) 58, 8681) confirmed that the conductivity increases to y = 1.5, at which point no additional Cl can be incorporated into the structure. For typical halogen species, such as Cl, Br, and I, it is impossible to further increase the halogen component. This disclosure overcomes this limitation by using pseudohalogen species, such as BH4, BF4, etc., which allow the limitation of component “X” in the argyrodite-type phase to be increased to a new upper limit of y = 2, which substantially increases the conductivity.

[0007] Another desired approach is to incorporate pseudohalogen species, such as BH4 and BF4, because these species have higher oxidation potentials compared to halogen species such as Cl and Br. Higher oxidation potentials can improve the electrochemical stability of high-voltage active materials. For example, U.S. Patent No. 10,411,295 describes the incorporation of the pseudohalogen species BH4 into the zLiBH4·(1-z)P2S5 system, which is used as a solid electrolyte. However, the conductivity of this material is limited to <2 mS / cm due to the constraints of its crystalline structure. Considering the limited availability of the component Li in this system, U.S. Patent No. 8,075,865 describes the formula Li... + (12-n-y) T n+ A 2- (6-y) X - (y)Failure to satisfy this means that formation of the argyrodite-type phase is not favorable. Furthermore, it is well known that all argyrodite-type materials having "T" = P and "A" = S contain the structural unit PS4 as the sole phosphorus-containing building block, as can be confirmed by using, for example, Raman spectroscopy. The Raman spectrum reported in U.S. Pat. No. 10,411,295 confirms that, due to the presence of alternative P-S bonds, the structure of this material is not argyrodite-type. In contrast, the present disclosure provides an argyrodite-type material incorporating the pseudohalogen species BH4, and is the first BH4-containing sulfide solid electrolyte that exhibits high conductivity >> 2 mS / cm.

[0008] Sakuda et al. (Sakuda, A.; Yamauchi, A.; Yubuchi, S.; Kitamura, N.; Idemoto, Y.; Hayashi, A.; Tatsumisago, M. ACS Omega (2018) 3(5), 5453-5458; hereinafter referred to as "Sakuda") describe Li according to U.S. Pat. No. 8,075,865 + (12-n-y) T n+ A 2- (6-y) X - (y) the so-called argyrodite-type material of the formula described, which incorporates "T" = P, "A" = S and "X" = BH4, with y = 1. The present disclosure differs from Sakuda in two important aspects. First, a significant difference in X-ray diffraction indicates a difference between the crystalline structure of Sakuda and the crystalline structure disclosed herein. In Sakuda, peaks in the range of 25-35° show higher relative intensity, indicating a first difference in the structures, and the absence of a diffraction peak at 14.6° indicates a second difference between the structure of Sakuda and the structure disclosed herein. Second, Sakuda teaches that in Li + (12-n-y) T n+ A 2- (6-y) X - (y) , the crystalline portion has y = 1, and it is taught that y > 1 is impossible, whereas in the present disclosure, y is greater than 1 (1 < y ≤ 2). Compared with the present disclosure, where 1 < y ≤ 2 and the measured conductivity is as high as 8.9 mS / cm, these structural and compositional characteristics result in a mediocre reported conductivity of 1.8 mS / cm for the material of Sakuda. Summary of the Invention

[0009] In one embodiment, the sulfide-germanium ore-type solid electrolyte material comprises Li, T, X, and A, wherein T is at least one of P, As, Si, Ge, Al, and B; X is BH4; and A is S, Se, or N. The solid electrolyte material may comprise glass-ceramic and / or mixed crystalline phases and exhibits high ionic conductivity and compatibility with high-voltage cathodes and lithium metal anodes.

[0010] In another embodiment, the sulfide-germanium ore-type solid electrolyte material includes Li, T, X, and A, wherein T is at least one element selected from the group consisting of P, As, Si, Ge, Al, and B; X is one or more halogens or BH4, BF4, NH2, or NO3 or mixtures thereof; and A is one or more of S, Se, and N; and in In X-ray diffraction measurements, the solid electrolyte material exhibits peaks at 2θ = 14.6° ± 0.25°, 15.3° ± 0.25°, and 25.1° ± 0.25°.

[0011] In yet another embodiment, the solid electrolyte material further comprises at least one of a glass-ceramic phase, a crystalline phase, and a mixed phase.

[0012] In another embodiment, the solid electrolyte material comprises a peak intensity ratio of 5:1 or less at 2θ = 15.3° ± 0.25° to the peak intensity at 14.6° ± 0.25°.

[0013] In another embodiment, the solid electrolyte material includes Li, T, X and A, wherein X includes one or more halogens or a mixture of BH4, BF4, NH2 or NO3.

[0014] In another embodiment, the solid electrolyte material comprises the formula LPS·zLiX, wherein LPS represents a mixture of Li2S and P2S5 in a glass-forming ratio or a mixture of Li2S and B2S3 in a glass-forming ratio, and LiX represents LiCl, LiBr, LiI, LiBH4, LiBF4, LiNH2 and LiNO3, and 0.25≤z≤4.

[0015] In another embodiment, the solid electrolyte material comprises the formula LPSX·zLiX, wherein LPSX comprises Li2S, P2S5 and LiX in a glass-forming ratio or a mixture of Li2S, B2S3 and LiX in a glass-forming ratio, wherein LiX comprises one or more of LiCl, LiBr, LiI, LiBH4, LiBF4, LiNH2 and LiNO3, and 0 <z≤25。

[0016] In another embodiment, the solid electrolyte material comprises Li, T, X, and A, wherein X comprises BH4, and wherein in The presence of a peak at 2θ = 14.6° ± 0.25° in the X-ray diffraction measurements was controlled by tuning specific synthesis conditions without changing the nominal stoichiometry.

[0017] In another embodiment, the solid electrolyte material includes the formula Li + (12-n-y) T n+ A 2- (6-y) X - (y) , where y>1.

[0018] In another embodiment, the solid electrolyte material includes the formula Li + (12-n-y) T n+ A 2- (6-y) X - (y) , where T=P, A=S, X=BH4, and y>1.

[0019] In another embodiment, the solid electrolyte material includes The crystalline phases with peaks at 2θ = 14.6°±0.25°, 15.3°±0.25° and 25.1°±0.25° in X-ray diffraction measurements, and one or more mixtures of LiBH4, LiBF4, LiNH2, LiNO3, LiSCN and LiOCN.

[0020] In another embodiment, the solid electrolyte material comprises 50% or more of a crystalline argillaceous-germanium-type phase, based on the total phase present in moles.

[0021] In another embodiment, the solid electrolyte material is included in the Raman spectroscopic measurement excited at 532 nm, at 423 ± 10 cm⁻¹. -1 The main peak, which is located at 250-700cm -1 The intensity ratio of other peaks present within the range is at least 2:1.

[0022] In another embodiment, the solid electrolyte material comprises an intensity ratio of 1 or greater between the peak at 2θ = 15.3° and the peak at 2θ = 17.5°.

[0023] In another embodiment, the lithium battery includes (a) a positive electrode active material layer containing a positive electrode active material; (b) a negative electrode active material layer containing a negative electrode active material; and (c) a solid electrolyte layer disposed between the positive electrode active material layer and the negative electrode active material layer, wherein at least one of the positive electrode active material layer, the negative electrode active material layer, and the solid electrolyte layer includes a sulfide solid electrolyte material containing a sulfide-type solid electrolyte material comprising: Li, T, X, and A, wherein T is at least one element selected from the group consisting of P, As, Si, Ge, Al, and B; X is one or more halogens or BH4, BF4, NH2, or NO3 or mixtures thereof; and A is one or more of S, Se, and N; and in In X-ray diffraction measurements, the solid electrolyte material exhibits peaks at 2θ = 146° ± 0.25°, 15.3° ± 0.25°, and 25.1° ± 0.25°.

[0024] In another embodiment, a method for manufacturing a solid electrolyte material includes: mixing and grinding a raw material composition comprising element A or compound Li2A or Li3N, element T or T, and compound LiX until the precursor material is substantially amorphous or alloyed to produce a composition of a final sulfide glass; optionally heating the sulfide glass at a heat treatment temperature equal to or greater than the crystallization temperature of the material to synthesize in Cu-Kα(1,2). The glass-ceramic having peaks at 2θ = 14.6° ± 0.25°, 15.3° ± -0.25°, and 25.1° ± 0.25° in X-ray diffraction measurements, wherein the solid electrolyte material comprises a glass-ceramic containing Li, T, X, and A, wherein T is at least one of P, As, Si, Ge, Al, and B; X is a halogen and / or BH4, BF4, NH2, or NO3; and A is at least one of S, Se, and N.

[0025] In another embodiment, the method for manufacturing a solid electrolyte material produces a final composition having an intensity ratio of 1 or greater between the peak at 2θ = 15.3° and the peak at 2θ = 17.5°.

[0026] In another embodiment, a method of manufacturing a solid electrolyte material includes mixing a suitable precursor comprising components Li, T, X, and A in a solvent capable of causing a reaction between the precursors, removing the solvent, and optionally heat-treating at a temperature equal to or greater than the crystallization temperature of the material, wherein the solid electrolyte material comprises a glass-ceramic containing Li, T, X, and A, wherein T is at least one of P, As, Si, Ge, Al, and B; X is a halogen and / or BH4, BF4, NH2, or NO3; and A is at least one of S, Se, and N. Attached Figure Description

[0027] This disclosure can be understood by referring to the following detailed description in conjunction with the figures briefly described below. It should be noted that, for purposes of clarity, some elements in the figures may not be drawn to scale.

[0028] Figure 1 This is a schematic cross-sectional view of an exemplary construction of a lithium solid-state electrochemical battery comprising a solid electrode composition according to an embodiment.

[0029] Figure 2 This is a flowchart of a process for manufacturing a solid electrolyte composition according to one embodiment.

[0030] Figure 3 shows the results of x-ray diffraction (XRD) analysis of various embodiments of the present disclosure. Specifically, Figure 3a The results are shown in relation to different synthesis conditions. Figure 3b The results show the results of different stoichiometry for the example composition Li3PS4·zLiBH4, and Figure 3c Results related to the use of different LPS stoichiometry for the compositions according to the invention are shown. X-ray diffraction measurements were performed using a Bruker D8 Advance with a copper X-ray source and a Lynxeye detector. The sample was sealed in a homemade sample holder with a beryllium window. Measurements were performed in steps of 0.02° in the range of 5–40°2θ.

[0031] Figure 4 shows the results of Fourier transform infrared spectroscopy (FTIR) analysis of various embodiments of this disclosure. Specifically, Figure 4a The results show the effects related to different synthesis conditions, and Figure 4b The results for the example composition Li3PS4·zLiBH4 are shown, with respect to different stoichiometry. FTIR measurements were performed using a Thermo Fisher Nicolet iS5 in ATR mode. The results were obtained at 0.24 cm⁻¹. -1 The data intervals were used to collect the cumulative data of 64 scans for each spectrum.

[0032] Figure 5 The results of Raman spectroscopy analysis of several embodiments of this disclosure are shown. Raman spectra were collected using a Jasco NRS-3100 spectrophotometer. The excitation source was a 532 nm wavelength focused through a 5× microscope objective using a 10 mW power and OD1 optical attenuator. A 2400 l / mm diffraction grating produced a 2.5 cm⁻¹ diffraction pattern. -1 Approximate resolution. 15 cumulatively collected spectra were obtained using a 10-second exposure.

[0033] Figure 6 shows the results of room-temperature ionic conductivity measurements according to this disclosure. Specifically, Figure 6a The results are shown in relation to different synthesis conditions. Figure 6b The results show the results of different stoichiometry for the example composition Li3PS4·zLiBH4, and Figure 6c The results shown are related to the use of different LPS stoichiometry for the compositions according to the invention. Ionic conductivity was measured as follows: Approximately 0.250 g of powder was loaded into a pellet die with a diameter of 16 mm, and the powder was pressed to 300 MPa for 2 minutes using a benchtop hydraulic press. The pressing pressure was released, and a measuring pressure of 8 MPa was applied. The cell was connected to a Biologic SP300 electrochemical workstation, and the complex impedance was measured in the range of 7 MHz–1 Hz using 100 mV excitation. The resulting spectrum was fitted and used to calculate the ionic conductivity. Detailed Implementation

[0034] In the following description, specific details are provided to provide a thorough understanding of various embodiments of the present disclosure. However, upon reading and understanding the specification, claims, and drawings of the invention, those skilled in the art will understand that some embodiments of the invention may be practiced without adhering to some of the specific details set forth herein. Furthermore, to avoid obscuring the present disclosure, some well-known methods, processes, apparatuses, and systems applicable to the various embodiments described herein are not disclosed in detail.

[0035] definition

[0036] In this document, the abbreviation "LPS" is used to denote an electrolyte phase consisting of Li₂S:P₂S₅ in a defined ratio. When not defined, a known ratio of 3Li₂S:P₂S₅ that produces the electrolyte phase Li₃PS₄ may be used. The term "semi-crystalline" can mean a partially crystalline region having a sufficiently small size to broaden peaks in X-ray diffraction, exhibiting both glassy and crystalline characteristics, containing crystalline and glassy phases of varying compositions, or any combination thereof. The term "crystalline phase" can be understood to mean a material comprising fully crystalline or "semi-crystalline" atomic orders. "Mechanochemical synthesis" can refer to a synthetic technique that uses a medium to mix precursor materials or abrasive energy to mix and / or react such materials. "Lithium-silver-germanium ore sample" and "Lithium-silver-germanium ore type" are used interchangeably to denote chemical relationships consistent with those defined in U.S. Patent No. 8,075,865 describing "lithium-silver-germanium ore": Li + (12-n-y) T n+ A 2- (6-y) X - (y) Materials.

[0037] Figure 1 This is a schematic cross-sectional view of an exemplary configuration of a lithium solid-state electrochemical battery incorporating the electrode compositions of this disclosure. The lithium solid-state battery 100 includes a positive electrode (current collector) 110, a positive active material layer (cathode) 120, a solid electrolyte layer 130, a negative active material layer (anode) 140, and a negative electrode (current collector) 150. The solid electrolyte layer 130 may be formed between the positive active material layer 120 and the negative active material layer 140. The positive electrode 110 is in electrical contact with the positive active material layer 120, and the negative electrode 150 is in electrical contact with the negative active material layer 140. The solid electrolyte composition described herein may be formed as a portion of the positive active material layer 120, the negative active material layer 140, and the solid electrolyte layer 130.

[0038] The positive electrode 110 may be formed of a material comprising, but not limited to, aluminum, nickel, titanium, stainless steel, or carbon. Similarly, the negative electrode 150 may be formed of copper, nickel, stainless steel, or carbon. If the negative electrode active material 140 possesses sufficient electronic conductivity and mechanical strength, then the negative electrode 150 may be omitted entirely. The positive electrode active material layer 120 may at least comprise a positive electrode active material comprising, but not limited to, metal oxides, metal phosphates, metal sulfides, sulfur, lithium sulfide, oxygen, or air, and may further comprise a solid electrolyte material (such as the solid electrolyte composition described herein), a conductive material, and / or a binder. Examples of conductive materials include, but are not limited to, carbon (carbon black, graphite, carbon nanotubes, carbon fibers, graphene), metal particles, filaments, or other structures. Examples of adhesives include, but are not limited to, polyvinyl chloride (PVC), polyaniline, poly(methyl methacrylate) ("PMMA"), nitrile butadiene rubber ("NBR"), styrene-butadiene rubber (SBR), PVDF, or polystyrene. The positive electrode active material layer 120 may, for example, comprise from 5 vol% to 80 vol% of the solid electrolyte composition as described herein. The thickness of the positive electrode active material layer 120 may range from, for example, 1 μm to 1000 μm.

[0039] The negative electrode active material layer 140 may at least comprise a negative electrode active material, which includes, but is not limited to, lithium metal, lithium alloys, Si, Sn, graphite carbon, and hard carbon, and may further comprise a solid electrolyte material (such as the solid electrolyte composition described herein), a conductive material, and / or a binder. Examples of conductive materials may include those used in the positive electrode material layer. Examples of binders may include those used in the positive electrode material layer. The negative electrode active material layer 140 may, for example, comprise 5 vol% to 80 vol% of the solid electrolyte composition described herein. The thickness of the negative electrode active material layer 140 may range from, for example, 1 μm to 1000 μm.

[0040] The solid electrolyte layer 130 contains one or more of the solid electrolyte compositions described herein. The solid electrolyte layer 130 may contain a solid electrolyte composition, for example, ranging from 10 vol% to 100 vol% as described herein. Furthermore, the solid electrolyte layer 130 may contain a binder or other modifier. Examples of binders may include those materials used in the positive electrode material layer, as well as other self-healing polymers and poly(ethylene) oxide (PEO). The thickness of the solid electrolyte layer 130 ranges from 1 μm to 1000 μm.

[0041] Despite Figure 1 While the term "solid-state electrochemical battery" indicates a layered structure, other shapes and configurations are known to be possible. Most generally, lithium solid-state batteries can be manufactured by providing a positive electrode active material layer, a solid electrolyte layer, and a negative electrode active material layer sequentially stacked and pressed between electrodes, and are provided with a casing.

[0042] Figure 2This is a flowchart of a process for manufacturing a solid electrolyte composition that can be used to construct a secondary electrochemical battery. Process 200 begins at preparation step 210, where any preparative actions, such as precursor synthesis, purification, and equipment preparation, may be performed. After any initial preparation, process 200 proceeds to step 220, where sulfur compounds, lithium compounds, and other compounds (as described herein) may be combined with suitable solvents and / or other liquids. Exemplary sulfur compounds may include, for example, elemental sulfur, phosphorus pentasulfide (P2S5), and lithium sulfide (Li2S), typically in powder form. Exemplary lithium compounds may include, for example, lithium metal (Li), lithium sulfide (Li2S), lithium chloride (LiCl), lithium nitride (Li3N), lithium borohydride (LiBH4), lithium fluoroborate (LiBF4), lithium amine (LiNH2), and lithium nitrate (LiNO3), typically in powder form. Exemplary solvents may include, for example, but not limited to, aprotic chain hydrocarbons (such as heptane, octane, or decane), aromatic hydrocarbons (such as benzene, toluene, or xylene), and other solvents having a low tendency to produce hydrogen sulfide gas upon contact with the precursor or final electrolyte composition. Solvents are not specifically limited, provided they remain partially or completely liquid during the milling process and do not participate in harmful reactions with the solid electrolyte precursor or final solid electrolyte composition. The ratios and amounts of various compounds are not specifically limited, provided that the combinations allow for the synthesis of the desired composition as indicated by the presence of specific X-ray diffraction features. Ratios and amounts may also vary depending on specific synthetic conditions. For example, as the solid electrolyte composition is prepared, it may be necessary to adjust the solvent volume to precursor mass ratio to ensure complete milling of the precursor to produce the desired solid electrolyte phase discussed herein.

[0043] The amount of solvent added to the composition is not limited, as long as the amount supports the desired composition for synthesizing the solid electrolyte material. Various solvents can be mixed with the mentioned compounds. Other materials, such as co-solvents or polymers, may also be added during this step. Furthermore, synthesis can be carried out without solvent.

[0044] Next, in step 230, the composition may be mixed and / or milled at a predetermined time period and temperature to produce a solid electrolyte as described above. The mixing time is not specifically limited, as long as it allows for proper homogenization and reaction of the precursors to produce the solid electrolyte. The mixing temperature is not specifically limited, as long as it allows for proper mixing and is not so high as to cause the precursors to enter a gaseous state. For example, proper mixing may be achieved in 10 minutes to 48 hours at a temperature of 0 to 120°C. In one embodiment, proper mixing may be achieved in 10 minutes to 36 hours. In another embodiment, proper mixing may be achieved in 10 minutes to 24 hours, and in yet another embodiment, proper mixing may be achieved in 10 minutes to 12 hours. Regarding the temperature at which proper mixing is performed, in some embodiments, the temperature may be in the range of 15 to 200°C. In another embodiment, the temperature at which proper mixing is performed is 20 to 150°C. In yet another embodiment, the temperature at which proper mixing is performed is 25 to 120°C. Mixing may be achieved using, for example, a planetary ball mill or a vertical mill. In some embodiments, the process described herein may be referred to as “mechanical-chemical synthesis.”

[0045] Next, in step 240, the composition may be dried in an inert atmosphere such as argon or nitrogen, or under vacuum, for a predetermined time period and temperature. After drying, heat treatment may be performed during optional step 250. The temperature of the heat treatment is not specifically limited, as long as it is equal to or higher than the temperature required to produce the crystalline phase of this disclosure or, if desired, to enhance ionic conductivity or lithium metal compatibility. The material produced by heat treatment step 250 may be single-phase and may also contain other crystalline phases, a glassy phase, and a small amount of precursor phase.

[0046] Generally, the heat treatment time is not limited, as long as it allows for the production of the desired composition and phase. The time can range from, for example, one minute to 24 hours. Furthermore, the heat treatment is carried out in an inert gas atmosphere (e.g., argon), a reducing atmosphere (e.g., hydrogen), or under vacuum. If the desired composition and phase are obtained during an earlier mixing or drying step, then the heat treatment step 250 can be completely omitted.

[0047] In the final step 260, the completed composition can be used to construct an electrochemical cell, such as... Figure 1 The battery.

[0048] Example 1

[0049] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 20.13 g Li3PS4 and 4.87 g LiBH4 (Sigma-Aldrich Co.). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground for 12 hours at 500 RPM in a Retsch PM 100 planetary mill. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0050] Example 2

[0051] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 20.13 g Li3PS4 and 4.87 g LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g zirconia grinding media and 60 ml xylene (Sigma-Aldrich). The mixture was ground at 500 RPM for 6 hours in a Retsch PM 100 planetary mill. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0052] Example 3

[0053] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 20.13 g Li3PS4 and 4.87 g LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground in a Retsch PM100 planetary mill at 350 RPM for 6 hours. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0054] Example 4

[0055] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 20.13 g Li3PS4 and 4.87 g LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground in a Retsch PM 100 planetary mill at 350 RPM for 3 hours. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0056] Example 5

[0057] The material produced in Example 4 was removed and heat-treated. A borosilicate beaker was loaded with a fabric heating mantle and preheated to 150°C inside an argon-filled glove box. The powder was introduced into the preheated beaker and treated for 10 minutes, then immediately removed from the heating mantle and allowed to cool naturally.

[0058] Example 6

[0059] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 23.13 g Li3PS4 and 1.87 g LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground in a Retsch PM100 planetary mill at 500 RPM for 12 hours. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0060] Example 7

[0061] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 12.92 g of Li3PS4 and 2.08 g of LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 240 g of zirconia grinding media and 45 ml of xylene (Sigma-Aldrich). The mixture was ground in a Retsch PM 100 planetary mill at 500 RPM for 12 hours. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0062] Example 8

[0063] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 12.08 g of Li3PS4 and 2.92 g of LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 240 g of zirconia grinding media and 45 ml of xylene (Sigma-Aldrich). The mixture was ground for 12 hours at 500 RPM in a Retsch PM 100 planetary mill. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0064] Example 9

[0065] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 11.01 g Li3PS4 and 3.99 g LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 240 g of zirconia grinding media and 45 ml of xylene (Sigma-Aldrich). The mixture was ground for 12 hours at 500 RPM in a Retsch PM 100 planetary mill. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0066] Example 10

[0067] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 10.35 g Li3PS4 and 4.65 g LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 240 g of zirconia grinding media and 45 ml of xylene (Sigma-Aldrich). The mixture was ground in a Retsch PM 100 planetary mill at 500 RPM for 12 hours. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0068] Example 11

[0069] First, Li₂S:P₂S₅ = 70:30 was prepared by mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 20.49 g of Li₂S:P₂S₅ = 70:30 and 4.51 g of LiBH₄ (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground for 12 hours at 500 RPM in a Retsch PM 100 planetary mill. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0070] Example 12

[0071] First, Li₂S:P₂S₅ = 80:20 was prepared by mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 19.71 g of Li₂S:P₂S₅ = 80:20 and 5.29 g of LiBH₄ (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground for 12 hours at 500 RPM in a Retsch PM 100 planetary mill. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0072] Example 13

[0073] First, Li₂S:P₂S₅ = 83.3:16.7 was prepared by mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 22.80 g of Li₂S:P₂S₅ = 83.3:16.7 and 2.20 g of LiBH₄ (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground for 12 hours at 500 RPM in a Retsch PM 100 planetary mill. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0074] Comparison Example 1

[0075] First, Li3PS4 was prepared via mechanochemical synthesis. Next, 4.10 g of Li3PS4 and 0.90 g of LiBH4 were added to an agate mortar and pestle and manually pulverized for 10 minutes, at which point a homogeneous mixture was observed. This material was studied without further processing.

[0076] Comparison Example 2

[0077] The material produced by Comparative Example 1 was removed and heat-treated. A borosilicate beaker was loaded with a fabric heating mantle and preheated to 140°C in an argon-filled glove box. The powder was introduced into the preheated beaker and treated for 10 minutes, then immediately removed from the heating mantle and allowed to cool naturally.

[0078] Comparison Example 3

[0079] First, Li3PS4 was prepared via mechanochemical synthesis. Next, an electrolyte composition was prepared from a precursor containing 24.34 g of Li3PS4 and 0.65 g of LiBH4 (Sigma-Aldrich). The precursor was added to a 250 ml zirconia grinding jar containing 400 g of zirconia grinding media and 60 ml of xylene (Sigma-Aldrich). The mixture was ground in a Retsch PM 100 planetary mill at 500 RPM for 12 hours. The material was collected, and the solvent was removed under vacuum at 70 °C.

[0080] In some embodiments, this disclosure may be implemented within a range of synthetic conditions and stoichiometry, and the examples and data presented herein are intended to aid in understanding the required conditions and scope. It should be understood that the data presented herein are non-exhaustive.

[0081] The effect of synthesis conditions is demonstrated in Examples 1 to 4 and Comparative Examples 1 to 2. Here, several observations are made to confirm different synthesis conditions using planetary ball milling. X-ray diffraction (XRD) is observed when the total energy input to the precursor is reduced during milling. Figure 3a), FTIR spectrum ( Figure 4a Raman spectroscopy Figure 5 ) and conductivity ( Figure 6a Specific variations in X-ray diffraction peaks can occur due to lower crystallinity or smaller crystallite size. Different levels of synthesis energy can cause differences in the ratio of X-ray peaks (CuKa radiation) at 14.6°±0.25° and 15.3°±0.25°, and this ratio may be related to factors such as… Figure 6a The ionic conductivity exhibited in the study is related to this. When the total energy input reaches a certain lower threshold, the product becomes an X-ray amorphous form, such as... Figure 3a The X-ray amorphous state observed in Example 4. X-ray amorphous state can refer to glassy, ​​nanocrystalline, or a combination of both, regions too small to be resolved mechanically into peaks. When the product synthesized by grinding is X-ray amorphous, it can be heat-treated to induce the crystallization and appearance of the phase of this disclosure. When the product of Example 4 was subjected to 150°C for 10 min to produce Example 5, substantial crystallization occurred and the phase of this disclosure was observed.

[0082] When inspect Figure 4a Further details of the synthesis process can be obtained by examining the FTIR spectra presented in the image. Figure 4a In this paper, data from Examples 1 to 5 are presented alongside the spectra of pure Li3PS4 and LiBH4 materials. The spectrum of LiBH4 shows distinct distinguishing features, and two of these peaks are representative of this material for comparison with Examples 1 to 5. For Examples 1 to 3, relatively minor differences were observed in the FTIR spectra. In the materials of the compositions and synthesis conditions described in these examples, the distinct features of LiBH4 have slightly softened and altered, indicating integration with Li3PS4 to form the phase of this disclosure. The spectra indicate that the BH4 units remain intact, but the current phase has a slightly different local environment compared to the environment in LiBH4. When examining the FTIR spectrum of Example 4, there are clear signs of the presence of the LiBH4 phase in the product, and the conductivity is low, such as... Figure 6a As shown in the figure. However, a subsequent heat treatment at 150°C for 10 minutes is sufficient to complete the integration of LiBH4, crystallize the phase of this disclosure, and increase the electrical conductivity by 6×.

[0083] The X-ray diffraction pattern of this disclosure, presented in Figure 3, shows that for optimal instrument resolution, using Br instead of BH4 for lithium-sulfur silver-germanium ore typically yields the same number of peaks and peak positions. Considering Br (196 pm) and BH4... -The similarity in ionic radius (193 pm) suggests a similar d-interval and peak position. This implies the presence of a crystalline phase typically found in lithium-based silver-germanium sulfide materials. The only atypical peak observed in the X-ray diffraction data is at 14.4° ± 0.25°, the existence and implications of which are discussed in detail elsewhere in this disclosure.

[0084] examine Figure 5 The Raman spectra of Examples 1 to 3 presented in the image show that at 423 cm⁻¹... -1 The main peak and at 391cm -1 The secondary peak. At 391cm. -1 The peak corresponds to P2S6 4- The PS vibration in the unit cell is an impurity phase introduced during the synthesis of the Li3PS4 precursor. Importantly, it is observed in the Raman spectrum at 423 cm⁻¹. -1 The main peak corresponds to PS4 3- PS vibrations within structural units. The crystalline structure of argentite-germanium ore-type materials is exclusively composed of PS4 units, and no other units (such as P2S6) exist in the structure. 4- P2S7 4- Given that the observed X-ray diffraction patterns show the number and position of typical peaks of argillium sulfide-germanium-type materials, and the Raman spectra show the presence of mainly PS4 local structural units, it is inferred that the materials disclosed herein are also mainly argillium sulfide-germanium-type materials.

[0085] Other details in the Raman spectra of Examples 1 to 3 are as follows: Figure 5 As shown in the illustration. Here, see at 452cm -1 The variation of the shoulder peak. It should be noted that the intensity of this peak appears to correlate with the energy / input during grinding synthesis, and subsequently, the intensity of this peak can also correlate with conductivity. This peak may indicate small-structure disorder that alters the local crystal symmetry, influencing ion migration.

[0086] Figure 3a Comparative Examples 1 and 2 shown in the diagram demonstrate that it is insufficient to simply mix the Li3PS4 and LiBH4 precursor phases and heat them to produce the phases of this disclosure, and further synthesis of energy inputs may be required, such as by means of a liquid-phase reaction to grind or alternative reaction pathways.

[0087] In another embodiment, other synthetic routes may be used. For example, the following method may be used to synthesize the solid electrolyte material discussed herein, the method comprising: mixing suitable precursors providing components Li, T, X, and A in a solvent capable of causing a reaction between the precursors; removing the solvent; and optionally performing heat treatment at a temperature equal to or higher than the crystallization temperature of the material.

[0088] Other embodiments of the present disclosure relate to the range of nominal stoichiometry of the present disclosure that can be implemented therein. Examples 6 to 10 and Comparative Example 3 serve as demonstrations of the range of LiBH4 fractions in the precursors. In general, the present disclosure is demonstrated in the LPS·zLiBH4 range where 0.25 < z < 4. Examples 6 to 10 confirm this range, and the resulting diffraction patterns are shown in Figure 3b . In all cases, the peaks of the present disclosure are observed. Comparative Example 3 demonstrates the result when z = 0.2. Only the peaks of the Li3PS4 precursor phase are observed, because the amount of LiBH4 available in the system is too low to substantially produce the crystalline phase of the present disclosure.

[0089] Checking the trend of electrical conductivity of Examples 6 to 10 as shown in Figure 6b , it is observed that the electrical conductivity increases from z = 0.7 to z = 3, and then decreases when the LiBH4 content is further increased to z = 3.7. Briefly, the electrical conductivity increases with the increase of the fraction of LiBH4 in the system until a limit, after which the electrical conductivity starts to decrease.

[0090] For Examples 6 to 8, the Figure 4b FTIR spectra shown in show that the B-H bonding is slightly changed from that found in pure LiBH4. No signature of LiBH4 is present in Examples 6 to 8. However, the spectra of Examples 9 to 10 clearly show the characteristic peaks of additional LiBH4 phase. The presence of the LiBH4 phase indicates that in the nominal compositions reported in Examples 9 to 10, the fraction of LiBH4 in the precursor is too high to be incorporated into a single phase.

[0091] The nominal composition of Example 8 corresponds to Li5PS4(BH4)2. The data presented herein describe the extent to which the present disclosure can be described as an argyrodite-type phase. With the understanding that typical argyrodite-type materials exist in the space group F-43m, Wyckoff positions 4a and 4d may be occupied by chalcogens (usually sulfur), halogens (usually Cl or Br), or pseudohalogens. Considering a hypothetical example involving the pseudohalogen BH4, when half of the available 4a+4d positions are filled with BH4, the nominal stoichiometry of the resulting argyrodite-type material will be Li6PS5(BH4). Further, if all available 4a+4d positions are filled with BH4, the nominal stoichiometry of the resulting argyrodite-type material will be Li5PS4(BH4)2. Therefore, the limit for the incorporation of halogens or pseudohalogens into argyrodite-type materials should be in Li + (12-n-y) T n+ A 2- (6-y) X - (y) when y = 2, because beyond this level, substantially no more halogens or pseudohalogens can enter the positions in the structure to maintain energetically favorable conditions.

[0092] Figure 4b FTIR data in the data only applies to Li + (12-n-y) T n+ A 2- (6-y) X - (y) The nominal composition of LiBH4 is found in the region where y > 2. Based on this observation, this disclosure first realizes a sulforaphite-germanium type material in which halogens or pseudohalogens occupy substantially all 4a and 4d Wyckoff sites, essentially producing a structure saturated with halogens or pseudohalogens. Because this has been extensively attempted but never achieved with halogens such as Cl and Br, it allows for the realization of Li... + (12-n-y) T n+ A 2- (6-y) X - (y) The findings of y=2 and this disclosure may be unique characteristics of pseudohalogens such as BH4.

[0093] Another embodiment of this disclosure relates to another range within which the nominal stoichiometry of this disclosure can be achieved. Using a system (Li₂S:P₂S₅):₂LiBH₄), Examples 1 and 11 through 13 compare the range of Li₂S:P₂S₅ ratios. In these embodiments, the nominal composition of the Li₂S:P₂S₅ fraction varies from 70:30 at the lower end to 83:17 at the upper end. Figure 3c The general observations of the X-ray diffraction results presented include the ratio of peaks at 14.6°±0.25° to 15.3°±0.25° and the variation in the relative amount of Li₂S impurities. In Example 12, with the 80:20 Li₂S:P₂S₅ composition, the glass-forming ratio is close to its limit, and a relatively high amount of Li₂S is observed. However, in… Figure 6c At CUHK, conductivity is typically observed to increase up to this limit. For the Li2S:P2S5 = 83:17 composition, there is excess Li2S in X-ray diffraction because this composition may exceed the range of glass-forming ratios; and the conductivity decreases due to the stoichiometric imbalance of the system and the strong presence of the Li2S impurity phase.

[0094] In another embodiment, a peak may be present centered at 2θ = 14.6° ± 0.25°. This peak may be a component of the main structure of the composition or a secondary phase. The presence of this peak is associated with an increase in ionic conductivity and is therefore desirable when high lithium conductivity is required. In this embodiment, component X is, for example, BH4. - BF4 -In the case of polyanionic species such as etc., this additional peak may result from rotation or displacement of polyhedral groups, such that vertex species (H, F, etc.) occupy normally unoccupied regions of the crystal structure and produce new diffraction peaks that are not observed when component X is a single anion (Cl - , Br - etc.). This diffraction peak may be a result of the polyanionic species itself or a result of new scattering induced when the surrounding structure relaxes and repositions to compensate for the movement of polyanions and lithium ions. Since rotation and displacement of polyhedra are generally associated with the migration of ionic charge carriers, the correlation between ionic conductivity and the intensity of this measurable diffraction peak can be understood by considering that the intensity of the peak itself depends on the rotation and displacement of anionic polyhedra.

[0095] The general chemical composition can be expressed as LPS·zLiX, wherein T, A and X represent elements as described herein, and LPS represents, for example, a mixture of Li2S and P2S5 in a glass-forming ratio and / or Li2S and B2S3 in a glass-forming ratio. The glass-forming ratio can range from 1:1 to 4:1 (for Li2S:P2S5) and from 1:1 to 3:1 (for Li2S:B2S3). In another embodiment, the Li2S:B2S3 component can be predominantly crystalline or predominantly glassy, as long as the mixing and / or grinding step is sufficient to sufficiently combine this material with other precursors in a manner that allows obtaining the desired electrolyte composition.

[0096] The composition can satisfy 0 < z ≤ 25. In another embodiment, the composition can satisfy 0.15 ≤ z ≤ 15. In another embodiment, the composition can satisfy 0.20 ≤ z ≤ 10. In yet another embodiment, the composition can satisfy 0.25 ≤ z ≤ 4. In still another embodiment, the composition can satisfy 1 ≤ z ≤ 3. The composition can be single-phase or mixed-phase, with additional crystalline phases identified by XRD peaks at 2θ = 17.5° and 18.2°. The composition can also contain crystalline phases associated with one or more lithium halides or lithium sulfide. As a typical sulfide material, the composition can be "glass-ceramic", wherein crystalline phases and glassy phases coexist.

[0097] In another embodiment, the general chemical composition can be expressed as LPSX·zLiX, wherein LiX comprises one or more of LiCl, LiBr, LiI, LiBH₄, LiBF₄, LiNH₂ and LiNO₃, and LPSX comprises a mixture of Li₂S, P₂S₅ and LiX in a glass-forming ratio, and Li₂S, B₂S₃ and LiX in a glass-forming ratio, wherein in some embodiments, the "X" in LPSX and the "X" in LiX are the same, and in another embodiment, the "X" in LPSX and the "X" in LiX are different. The glass-forming ratio may range from 1:1:1 to 4:1:4 (for Li₂S:P₂S₅:LiX) and from 1:1:1 to 3:1:4 (for Li₂S:B₂S₃:LiX). In some embodiments, LiX comprises LiBH₄, LiBF₄, LiNH₂ and LiNO₃. In another embodiment, LiX is LiBH₄. The composition may satisfy 0 < z ≤ 25, and in another embodiment, the composition may satisfy 0 < z ≤ 15. In another embodiment, the composition may satisfy 0 < z ≤ 10. In still another embodiment, the composition may satisfy 0 < z ≤ 4. In still another embodiment, the composition may satisfy 0 < z ≤ 2. The composition may be single-phase or mixed-phase, with additional crystalline phases identified by XRD peaks at 2θ = 17.5° and 18.2°. The composition may further contain crystalline phases associated with one or more lithium halides or lithium sulfide. As a typical sulfide material, the composition may be a "glass-ceramic", in which a crystalline phase and a glassy phase coexist.

[0098] in an X-ray diffraction (XRD) measurement, the peak height ratio between the peak at 2θ = 15.3°±0.25° and the peak at 14.6°±0.25° may be 25:1 or less. In another embodiment, in an X-ray diffraction (XRD) measurement, the peak height ratio between the peak at 2θ = 15.3°±0.25° and the peak at 14.6°±0.25° may be 20:1 or less. In still another embodiment, in an X-ray diffraction (XRD) measurement, the peak height ratio between the peak at 2θ = 15.3°±0.25° and the peak at 14.6°±0.25° may be 10:1 or less. In still another embodiment, in an X-ray diffraction (XRD) measurement, the peak height ratio between the peak at 2θ = 15.3°±0.25° and the peak at 14.6°±0.25° may be 5:1 or less. In still another embodiment, in an X-ray diffraction (XRD) measurement, the peak height ratio between the peak at 2θ = 15.3°±0.25° and the peak at 14.6°±0.25° may be 2:1 or less. In another embodiment, In X-ray diffraction (XRD) measurements, the peak height ratio between peaks at 2θ = 15.3° ± 0.25° and 14.6° ± 0.25° can be 1.5:1 or less. These peaks can be spaced 0.3° or more apart.

[0099] The exemplary composition is defined as LPS·2LiX=Li5PS4(BH4)2. Such compositions produce the semi-crystalline phase of this disclosure. The structure of this semi-crystalline phase contributes to high ionic conductivity, and the presence of the hydride component helps to form a stable, low-resistance interface for lithium metal and high-voltage cathode active materials.

[0100] Crystalline or semi-crystalline phases produced by compositions such as Li5PS4(BH4)2 can adopt the typical cubic structure of lithium-sulfur silver-germanium ore with space group F-43m, or a very similar structure with slightly altered symmetry. The above provides the basic principle for explaining how rotation and displacement of the polyanionic components can cause atomic occupancy of undefined lattice positions within the framework of the F-43m space group, thus altering symmetry. The adoption of this type of structure is not readily apparent. Consider the chemical system Li... 7-y PS 6-y X y It has been confirmed that when X = Cl, the solid solution limit is y = 1.5, and this limit decreases for X = Br, y = 1.25. This is because Br has a larger ionic radius than Cl [Nazar, Angewandte Chemie, 2019], because BH4 - The ionic radius of Br - Similarly, the solid solution limit could be expected to be y ≤ 1.25. However, in this disclosure, using, for example, BH4 as a pseudohalogen, this limit is y > 1.25, as evidenced by the trend in conductivity and the absence of the LiBH4 phase in X-ray diffraction and FTIR spectral analyses. Furthermore, the known compound Ag5PS4Cl2 [Jorgens, Solid State Sciences, 2007] employs an orthorhombic crystal structure (Amm2) that is extremely different from the cubic lithium-silver-germanium sulfide family (F-43m), and currently no known lithium analogues have this composition. Therefore, this disclosure may include Li 7-y PS 6-y X y The first example of a lithium-ion conductor with a cubic argentite-germanium sulfide structure having a medium or pseudohalogen level close to y=2.

[0101] In another embodiment, the system EPS·yLiX can produce a crystalline portion and a glassy portion having a nominal composition of Li5PS4(X)2. The ratio of the crystalline portion to the glassy portion is then determined using a nominal starting composition. The glassy portion may include an ionically conductive material and may have a composition similar to that of the LPS precursor. When the amount of LiX is higher than that supported by the amount of LPS, the resulting material may include a crystalline portion of Li5PS4(X)2, a glassy or crystalline LiX, and an additional glassy phase. In some embodiments, LiX may be LiBH4, wherein component X is BH4.

[0102] Compared to existing technologies, the enhanced conductivity of this disclosure is likely due to a unique ionic conduction mechanism. For example, BH4 - The polyanionic nature of the anions allows for a "paddlewheel" effect, whereby the rotational freedom of the anionic units allows lithium ions to be transported more easily by altering the local potential energy space during rotation. Furthermore, the compositions presented herein can benefit from, for example, the use of BH4 - The disorder introduced by anions is observed, as seen in the low-intensity XRD pattern with broadened peaks. It is well known that disorder at the S and Cl / Br sites in Cl- and Br-containing silver-germanium sulfide ores causes high conductivity, but the lack of such disorder in I-containing silver-germanium sulfide ores causes low conductivity. This type of disorder or localized lattice strain near the BH4 unit can exist in this invention and cause enhanced ionic conductivity.

[0103] Furthermore, this disclosure can be for nanocrystals with an inherently crystalline region size of about 100 nm or smaller. This can be a result of process conditions or reaction mechanisms in the precursor and may yield benefits for ionic conductivity and operation at high current densities in the case of a lithium metal anode. In the case of nanocrystal regions, a more uniform SEI can develop at the interface with the lithium metal anode, which can facilitate support for high current densities without the need for dendrite nucleation and growth.

[0104] Besides microstructure considerations, the enhanced stability compared to prior art compositions when used in combination with a lithium metal anode can stem from several factors related to the chemical properties of the materials. Particularly for embodiments including hydride or amide species, the SEI formed in contact with lithium metal can exhibit lower overall charge transfer resistance due to the presence of suitable conductive lithium hydride species and the dilution of any poorly conductive lithium sulfide species. The arrangement and structure of the SEI components can be such that they produce a more uniform electric field distribution, ion flow, and / or lithium plating / stripping. Furthermore, the surface energy of the compositions of the present invention allows for good wetting by lithium metal and / or maintaining mechanical contact during higher levels of interfacial polarization or plating / stripping rates. In this context, "enhanced stability" can mean using higher current densities without unexpected voltage drops or short circuits, or longer cycle life, or higher coulombic efficiency. "Low-voltage" anode active materials can include, but are not limited to, lithium metal, lithium alloys, Si, Sn, graphitic carbon, hard carbon, composites of these, or materials with operating voltages close to or below 1.0V and Li / Li + Other materials or composite materials.

[0105] It has been observed that structural modification or introduction of secondary phases may lead to an increase in ionic conductivity. These modifications can be controlled during the synthesis process by adjusting the milling speed or temperature, or by controlling the total energy input to the precursor composition.

[0106] During synthesis, gases may be generated. The presence of gaseous species indicates that the final composition may differ slightly from the nominal starting composition. Gas generation may be related to specific synthetic conditions and, further, to observations of structural modifications or secondary phase generation as described above.

[0107] The structural modifications or presence of secondary phases described above are associated with reduced performance of lithium metal anodes. This indicates that synthesis-related chemical changes, as demonstrated by gas generation during milling synthesis, lead to alterations in the composition and properties of the SE-Li interface. Therefore, to achieve maximum performance when using lithium metal anodes, it may be necessary to synthesize the compositions of this invention under conditions that minimize the structural modifications or secondary phases described above.

[0108] When used as part of a positive electrode active material layer and a high-voltage cathode active material combination, it achieves a stability advantage over prior art compositions, which may stem from the chemical properties of the compositions of the present invention. (Incorporating, for example, BH4) - Or BF4 - The "superhalogens" may lead to an overall increase in the oxidation potential of the electrolyte composition due to the higher electron affinity of these species.

[0109] The features described above and those claimed below can be combined in various ways without departing from the scope of the invention. The foregoing examples illustrate some possible non-limiting combinations. Therefore, it should be noted that the subject matter contained in the above description or shown in the drawings should be interpreted in an illustrative rather than limiting sense. The above embodiments should be considered as examples of this disclosure and not as limitations on the scope of this disclosure. In addition to the foregoing embodiments of this disclosure, a review of the detailed description and drawings will reveal other embodiments of this disclosure. Therefore, many combinations, arrangements, variations, and modifications of the foregoing embodiments of this disclosure not expressly set forth herein will still fall within the scope of this disclosure. The appended claims are intended to cover the general and specific features described herein, as well as all statements that can be linguistically said to fall within the scope of the inventive methods and systems.

Claims

1. A sulfide-germanium ore type solid electrolyte material, comprising: The solid electrolyte material is composed of Li, T, X, and A, wherein T is at least one element selected from the group consisting of P, As, Si, Ge, Al, and B; X is one or more halogens or BH4, BF4, NH2, or NO3 or mixtures thereof; A is one or more of S, Se, and N; and the solid electrolyte material exhibits peaks at 2θ = 14.6° ± 0.25°, 15.3° ± 0.25°, and 25.1° ± 0.25° in X-ray diffraction measurements at Cu-Kα(1,2) = 1.5418 Å, and wherein the solid electrolyte material has a peak at 423 cm⁻¹. -1 The Raman spectrum of the peak, wherein the peak at 423 cm⁻¹ -1 The peak is between 200-700 cm. -1 The peak with the highest intensity is within the range.

2. The solid electrolyte material according to claim 1, further comprising at least one of a glass-ceramic phase, a crystalline phase, and a mixed phase.

3. The solid electrolyte material according to claim 1, wherein the intensity ratio of the peak at 2θ = 15.3° ± 0.25° to the peak at 14.6° ± 0.25° is 5:1 or less.

4. The solid electrolyte material according to claim 1, wherein X comprises one or more halogens or a mixture of BH4, BF4, NH2 or NO3.

5. The solid electrolyte material according to claim 1, comprising the formula LPS•zLiX, wherein LPS represents a mixture of Li2S and P2S5 in a glass-forming ratio or a mixture of Li2S and B2S3 in a glass-forming ratio, and LiX represents LiCl, LiBr, LiI, LiBH4, LiBF4, LiNH2 and LiNO3, and 0.25≤z≤4.

6. The solid electrolyte material according to claim 1, comprising the formula LPSX•zLiX, wherein LPSX comprises a mixture of Li2S, P2S5 and LiX in a glass-forming ratio or a mixture of Li2S, B2S3 and LiX in a glass-forming ratio, wherein LiX comprises one or more of LiCl, LiBr, LiI, LiBH4, LiBF4, LiNH2 and LiNO3, and 0 <z≤25。 7. The solid electrolyte material according to claim 1, wherein X comprises BH4, and wherein the presence of a peak at 2θ = 14.6° ± 0.25° in X-ray diffraction measurements at Cu-Kα(1,2) = 1.5418 Å is controlled by tuning specific synthesis conditions without changing the nominal stoichiometry.

8. The solid electrolyte material according to claim 1, comprising the formula Li + (12-n-y) T n+ A 2- (6-y) X - (y) , where y>1.

9. The solid electrolyte material according to claim 1, comprising the formula Li + (12-n-y) T n+ A 2- (6-y) X - (y) , where T = P, A = S, X = BH4, and y > 1.

10. The solid electrolyte material according to claim 1, comprising a crystalline phase having peaks at 2θ = 14.6° ± 0.25°, 15.3° ± 0.25° and 25.1° ± 0.25° in X-ray diffraction measurements of Cu-Kα(1,2) = 1.5418 Å, and a mixture of one or more of LiBH4, LiBF4, LiNH4, LiNO3, LiSCN, and LiOCN.

11. The solid electrolyte material according to claim 1, comprising 50% or more of a crystalline argillaceous sulfide-germanium type phase based on the total phase present in moles.

12. The solid electrolyte material according to claim 2, wherein the intensity ratio of the peak at 2θ = 15.3° to the peak at 2θ = 17.5° is 1 or greater.

13. A lithium battery comprising: (a) Positive electrode active material layer, which contains positive electrode active material; (b) A negative electrode active material layer containing negative electrode active material; as well as (c) A solid electrolyte layer disposed between the positive electrode active material layer and the negative electrode active material layer, wherein at least one of the positive electrode active material layer, the negative electrode active material layer and the solid electrolyte layer comprises a sulfide solid electrolyte material containing a sulfide-type solid electrolyte material comprising: Li, T, X and A, wherein T is at least one element selected from the group consisting of: P, As, Si, Ge, Al and B, X is one or more halogens or BH4, BF4, NH2 or NO3 or mixtures thereof, and A is one or more of S, Se and N; and in X-ray diffraction measurements at Cu-Kα(1,2) = 1.5418 Å, the solid electrolyte material has peaks at 2θ = 14.6° ± 0.25°, 15.3° ± 0.25° and 25.1° ± 0.25°, and wherein the solid electrolyte material has a peak at 423 cm⁻¹. -1 The Raman spectrum of the peak, wherein the peak at 423 cm⁻¹ -1 The peak is between 200-700 cm. -1 The peak with the highest intensity is within the range.

14. A method for manufacturing a solid electrolyte material, comprising mixing and grinding a raw material composition comprising element A or compound Li2A or Li3N, element T or T, with compound LiX until the precursor material is substantially amorphous or alloyed to produce a composition of a final sulfide glass; heating the sulfide glass at a heat treatment temperature equal to or greater than the crystallization temperature of the material to synthesize a glass-ceramic having peaks at 2θ = 14.6° ± 0.25°, 15.3° ± 0.25°, and 25.1° ± 0.25° in X-ray diffraction measurements of Cu-Kα(1,2) 1.5418 Å. The solid electrolyte material mentioned above includes glass-ceramics containing Li, T, X, and A. Wherein T is at least one of P, As, Si, Ge, Al, and B; X is a halogen and / or BH4, BF4, NH2, or NO3; A is at least one of S, Se, and N; and The solid electrolyte material described herein has a 423 cm -1 The Raman spectrum of the peak, wherein the peak at 423 cm⁻¹ -1 The peak is between 200-700 cm. -1 The peak with the highest intensity is within the range.

15. The method of claim 14, wherein the intensity ratio of the peak at 2θ = 15.3° to the peak at 2θ = 17.5° is 1 or greater.

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