Rapid production method to produce lithium argyrodite solid electrolytes for solid state batteries

Abstract

In a first aspect, the invention relates to a battery, typically a rechargeable secondary battery; in a second aspect, the invention relates to an improved electrolyte for such a solid-state battery, i.e. a medium that includes ions in said battery and conducts electricity by the movement of these ions rather than by electrons; in a third aspect, the invention relates to a method of producing such a solid crystalline electrolyte; and in a fourth aspect, the invention relates to a product obtained by said method. The invention provides an improved battery performance.

Description

Technical Field

[0001] In a first aspect, the present invention relates to a battery, typically a rechargeable secondary battery; in a second aspect, the present invention relates to an improved electrolyte for such a solid-state battery, i.e., a medium comprising ions in said battery and conducting electricity through the movement of these ions rather than through electrons; in a third aspect, the present invention relates to a method for producing such a solid crystalline electrolyte; and in a fourth aspect, the present invention relates to a product obtained by said method. The present invention provides and improves battery performance.

[0002] Related applications This application claims priority to Dutch patent application NL2035165, filed on June 23, 2023, in the name of Delft University of Technology, Netherlands.

[0003] For all purposes, the entire contents of the applications cited above and all priority documents referenced in the application data sheet submitted with this application are hereby incorporated by reference. Background Technology

[0004] This invention belongs to the field of secondary electrochemical batteries (commonly referred to as rechargeable batteries). Such batteries are capable of generating electrical energy from (e)chemical reactions, or using electrical energy to initiate (e)chemical reactions, such as during charging. Electrochemical batteries that generate current are called voltaic cells or primary cells, while electrochemical batteries that generate chemical reactions, for example, via electrolysis, are called electrolytic cells. This invention focuses on primary cells, such as batteries. A battery can consist of one or more individual cells. Individual cells can be connected in parallel, series, or a combination thereof. Such individual cells effectively function as both primary cells and electrolytic cells during discharge / charging. They are used to store electrical energy during charging and release electrical energy during discharge.

[0005] Monovalent ion batteries, such as lithium-ion or sodium-ion batteries, can be used for energy storage and belong to a class of rechargeable batteries. These monovalent cation batteries are widely used, for example in portable electronic devices, electric vehicles, and energy storage devices. In these batteries, lithium ions can move back and forth, from the negative electrode to the positive electrode during discharge and vice versa during charging. For rechargeable batteries, the term cathode refers to the electrode that is reduced during discharge cycles; for lithium-ion batteries, the positive electrode is called the cathode, which is usually a lithium-based electrode. Li-ion batteries can use intercalated lithium compounds as an electrode material. These batteries have certain advantages over other energy storage devices, such as relatively high energy density, low self-discharge rate, and no memory effect. Typical density characteristics are specific energy density up to 250 Wh / kg, volumetric energy density up to 700 Wh / L, and specific power density up to 1500 W / kg. The performance of these batteries can be improved, such as in terms of extended lifespan, energy density, safety, cost, and charging speed.

[0006] Specifically, this invention relates to a solid-state battery. Solid-state batteries use solid electrodes and solid electrolytes instead of the commonly used liquid or polymer gel electrolytes, such as those found in lithium-ion batteries. Several drawbacks hinder the widespread adoption of these batteries. On the other hand, solid-state batteries are considered to offer solutions to many problems common in liquid Li-ion batteries, such as flammability, voltage limitation, lithium dendrite growth, unstable solid electrolyte phase interface formation, poor cycle performance, and poor strength. Materials suggested for use as solid electrolytes in solid-state batteries include ceramics and solid polymers. These materials may be safer and have higher energy densities compared to liquid variants, but are much more expensive. Challenges to widespread adoption include the energy density and power density of the power supply unit, durability, material cost, sensitivity, stability, capacity, ion depletion, charging speed, and cycle performance. In addition, prior art devices often have too many and / or too large passive components. Some of these devices suffer from internal mechanical stress, lower capacity, and shortened cycle life. In this respect, Si can be considered as an anode material, but due to its role in the formation of Li... x Si y (such as Li) 4.4 The volume expansion is large when using Si, so it is generally not applicable.

[0007] Several materials, such as silver-germanium sulfide (SFS), have been considered for use in solid-state electrolytes; the term may refer to an uncommon silver-germanium sulfide mineral with the formula Ag8GeS6. However, this is not a material of particular interest. The SFS group of minerals encompasses several other subgroups besides the Ag subgroup. Therefore, the term SFS is also used for other materials with similar crystal structures, particularly lithium-based SFS materials, which have indeed attracted researchers' interest as potential solid-state electrolytes for lithium-ion batteries. These materials offer some improvements over, for example, existing materials such as garnet-type materials or NASICON-like materials, in terms of ionic conductivity. However, production methods are typically expensive, and the quality of the obtained materials remains suboptimal. Furthermore, only relatively large particles are produced, typically on the order of approximately 10 µm or larger.

[0008] Li-ion batteries typically consist of a LiCoO2 cathode and a graphite anode. During charging, Li ions are transported to and absorbed by the electrodes (usually graphite electrodes) by intercalating them into a planar atomic graphite structure. The specific capacity of the materials used in these batteries is approximately 372 mAh / g (Ashuri et al., *Nanoscale*, Vol. 8, 74 (2016)). A single Li-ion or Na-ion salt is typically used, and sometimes two salts are employed, with one being the dominant salt at a higher concentration, typically LiPF6. Generally, liquid Li-ion battery electrolytes also include at least two solvents, such as EC / DMC, and small amounts of additives.

[0009] When a potential is applied to a battery, cations are attracted to the electrode with a large number of electrons, while anions are attracted to the electrode lacking electrons. The movement of anions and cations in opposite directions within the battery develops into an electric current. Therefore, the electrolyte conducts electricity when the electrode is in contact with the electrolyte and a voltage is applied to or obtained from the electrode. An electrochemical reaction occurs at the cathode, providing electrons to the electrolyte and the electrolyte providing ions to the electrode. Another electrochemical reaction occurs at the anode, consuming electrons from the electrolyte. Thus, a charge distribution, such as a cloud of negative charge, typically with a gradient, forms around the cathode, and similarly, a positive charge forms around the anode. In the absence of ions, the charge around the electrodes slows the continuous flow of electrons; diffusion of charged matter to the other electrode is restricted. In a battery, two materials with different electron affinities are used as electrodes; electrons flow from one electrode to the other outside the battery, while inside the battery, the circuit is closed by the ions of the electrolyte. Here, electrode reactions convert chemical energy into electrical energy.

[0010] Incidentally, Huang Wenze and others ( https: / / doi.org / 10.1039 / D0MA00115E This paper elucidates the conduction mechanism in oxygen-substituted lithium conductors, wherein the conductor is composed of Li... 6.15 Al 0.15 Si 1.35 S 6−x O x(LASSO) systems are constructed, which are members of the argentite-germanium type family and possess superionic conductivity, making them suitable for all-solid-state batteries. The crystal structure, ionic conductivity, and electrochemical properties of these systems are studied using powder X-ray and neutron diffraction combined with impedance spectroscopy and cyclic voltammetry measurements. WO 2022 / 210471 A1 describes a solid electrolyte containing Li, P, S, halogens, and element M (where M represents at least one element selected from silicon (Si), tin (Sn), antimony (Sb), germanium (Ge), and boron (B), comprising a crystal phase having an argentite-germanium type crystal structure. The molar ratio of S to P and element M, S / (P+M), satisfies 3.5. US 2022 / 166056 A1 describes a lithium-argentite-germanium ion superconductor containing halogen elements and a method for its preparation, wherein the argentite-germanium type crystal structure and lithium-ion conductivity can be maintained by combining specific elements in specific molar ratios. US 2021 / 119247A1 describes sulfide-based lithium-silver-germanium ion superconductors containing multiple chalcogenides and methods for their preparation. More specifically, it provides sulfide-based lithium-silver-germanium ion superconductors containing multiple chalcogenides and methods for their preparation. These superconductors and methods can significantly improve lithium-ion conductivity by replacing sulfur (S) in PS4 3-tetrahedrons with chalcogenides other than sulfur (S), such as selenium (Se), while maintaining the silver-germanium ion crystal structure of sulfide-based solid electrolytes represented by Li6PS5Cl.

[0011] Therefore, the present invention relates to an improved power supply unit, particularly a battery, which solves one or more of the aforementioned problems and disadvantages of the prior art, thereby providing reliable results without compromising functionality and advantages. Summary of the Invention

[0012] One object of this invention is to overcome one or more limitations of existing power supply units and their manufacturing methods, and to at least provide an alternative to them. This invention provides an improved electrolyte for solid-state batteries, such as an electrolyte with higher ionic conductivity, and a faster and more energy-efficient method for synthesizing solid electrolyte materials. High conductivity is considered necessary for fast charging and high-power applications, and more generally, provides for more efficient use of electrode capacity. Existing synthesis methods are time-consuming and energy-intensive (e.g., annealing times of seven to fourteen days at 550°C), and produce only small quantities of solid electrolytes. The inventors have developed a synthesis method that can produce these materials in a much more efficient manner. Notably, lithium-sulfur silver-germanium ore superionic conductors have attracted attention as potential solid electrolytes for all-solid-state batteries due to their high ionic conductivity and ease of processing. These materials are capable of converting halides (Li... 6-x PS 5-xHal 1+x The introduction of Hal (Cl, Br, and I) into the crystal structure of silicogermanium sulfide may significantly affect the distribution of lithium across a wide range of accessible crystal sites. Furthermore, in Wyckoff 4 d At the site of S 2− With Hal − The anions create a structural disorder. Both have been found to strongly influence ionic conductivity. In this invention, the synthesis method of silver sulfide germanite differs from existing techniques, resulting in increased (and therefore higher) ionic conductivity and a rapid crystallization method for the silver sulfide germanite group. Specifically, the inventors investigated bromine-substituted p-lithium silver sulfide germanite (Li... 6−x PS 5−x Hal 1+x Hal = Cl, Br, I, Cl y Br 1-y and Cl 0.33 Br 0.33 I 0.33 The inventors investigated the influence of the range (0.0 ≤ x ≤ 0.5) and designed structural disorder by changing the synthesis scheme. For example, X-ray diffraction, neutron diffraction, and electrochemical impedance spectroscopy revealed a correlation between lithium substructure, structural disorder, and ion transport. The inventors discovered that high ionic conductivity and [the structure located in Li] can be obtained. + 4 in the center of the "cage" d The lower average negative charge at the site is attributed to S 2− Partially replaced by halides and mixed halides. This improves the diffusivity of Li ions within the unit cell. Additionally, an extra T4 Li was identified. + This provides additional pathways for long-range lithium-ion diffusion. For example, quenched Li₂ exhibits the highest degree of structural disorder. 5.5 PS 4.5 Br 1.5 The ionic conductivity increased to 9 mS / cm. -1 -10 mS cm -1 Compared to Li6PS5Br, which has the lowest structural disorder, the conductivity is improved by 11 times. Furthermore, a modified synthesis method for chloride-rich silver-germanium sulfide, incorporating increased pressure and higher chloride content during synthesis, resulted in a 5-fold increase in ionic conductivity compared to Li6PS5Cl. Structural disorder and halide substitution have been found to affect lithium substructure and transport properties, which can be adjusted by this synthesis method, for example, to achieve higher ionic conductivity. In a first aspect, the present invention relates to an electrolyte for solid-state batteries, said electrolyte comprising at least one solid single-crystal electrolyte, wherein the solid single-crystal electrolyte is selected from A… 6-x ZE 5-x Hal 1+x and A 6+x Z1-x M 1-x HAVE BEEN 5-x Example 1+xAt least one of the following, wherein A is selected from Li, Na and their first combination, wherein Z is selected from P, As, Sb and their second combination, wherein M is selected from Si, As, Ge, Sn and Sb and their third combination, wherein E is selected from O, S, Se, Te and their fourth combination, wherein Hal is selected from Cl, Br, I or a mixed halide as their fifth combination, and wherein x is <-1; 1.0], particularly <-1; 0.75], especially wherein x is not -0.9 to -1. The term solid single-phase crystalline electrolyte as used herein refers to a single-phase crystalline solid electrolyte. The term crystallization is a well-known chemical term for solid materials whose components (such as atoms, molecules or ions) are arranged in a highly ordered microstructure, thus forming a lattice extending in all directions. The three forms or main categories of crystallization are: i) single crystalline, also called monocrystalline; ii) polycrystalline; and iii) amorphous. In single-crystal materials, the lattice of the entire sample is continuous and unbroken, with no grain boundaries reaching the sample edges. The atomic arrangement is nearly perfect. In polycrystalline materials, the material is composed of many microcrystalline particles, called microcrystals or grains. Although polycrystalline materials are crystals with a periodic atomic arrangement, the polycrystalline material as a whole does not have a periodic atomic arrangement because the periodic pattern breaks at the grain boundaries. Within a group of polycrystalline materials, the number of grain types can vary. If a polycrystalline material consists of one type of grain, it is called a single-phase polycrystalline material. If a polycrystalline material consists of multiple types, such as three types of grains, it is called a three-phase polycrystalline material. Solids that are neither single-crystal nor polycrystalline, such as glass, are called amorphous solids and do not have a periodic arrangement, even at the microscopic level. This invention relates to a single-phase crystalline solid electrolyte, which is therefore arranged in a specific structure with a higher lithium-ion mobility in the unit cell. Single-crystal materials can exist in mixed-crystal form. A mixed crystal is a crystal comprising two or more elements (also called ions or molecules) that occupy different sites in the crystal lattice. These elements can substitute for each other in the lattice due to their similar molecular structures and shapes. The abbreviations Fe, Mn, Li, Na, Co, Ni, Al, Sn, Mg, Ag, P, As, Sb, In, Si, B, C, N, Ge, O, H, Sn, S, Se, Te, F, Cl, Br, and I as used herein refer to specific chemical elements known in the periodic table, and specifically to, for example, lithium (Li), sodium (Na), phosphorus (P), arsenic (As), antimony (Sb), silicon (Si), germanium (Ge), tin (Sn), oxygen (O), sulfur (S), selenium (Se), tellurium (Te), chlorine (Cl), bromine (Br), and iodine (I). Terms used herein such as alloy, transition metal, and transition metal alloy are known to those skilled in the art.Alloy is a general chemical name for a mixture of chemical elements, where at least one element is a metal, resulting in an impure substance that retains metallic properties. Transition metals (also called transition elements) are chemical elements in the d-block of the periodic table (Groups 3 to 12). The solid single-phase crystalline electrolyte of the present invention has demonstrated significant advantages over prior art electrolytes, for example, in terms of its ionic conductivity.

[0013] In a second aspect, the present invention relates to a solid-state battery comprising at least one first electrode, at least one second electrode, and at least one solid single-phase crystalline electrolyte as taught herein, wherein the at least one solid single-phase crystalline electrolyte is disposed between and in contact with the first and second electrodes.

[0014] In a third aspect, the present invention relates to a method for producing a solid crystalline electrolyte, wherein the solid electrolyte to be produced comprises A 6-x ZE 5-x Hal 1+x and A 6+x Z 1-x M 1-x E 5-x Hal 1+xAt least one of the following, wherein A is selected from Li, Na and a first combination thereof, wherein Z is selected from P, As, Sb and a second combination thereof, wherein M is selected from Si, Ge, As, Sn and Sb and a third combination thereof, wherein E is selected from O, S, Se, Te and a fourth combination thereof, wherein Hal is selected from Cl, Br, I and a fifth combination thereof, and wherein x is <-1; 1.0], particularly <-1; 0.75], especially wherein x is not -0.99 to -1, providing substantially molar amounts of precursors and forming a mixture thereof, wherein the precursors are selected from combinations of A, M, Z, E, ZE and AHal, especially wherein E is provided in excess of 1.01 to 1.2 times the said molar amount, milling the mixture during milling time, thereby obtaining a milled mixture, heating the milled mixture at high temperature during heating time, thereby forming an electrolyte, and cooling the heated mixture, thereby obtaining a solid crystalline electrolyte. The phrase "molar amount" as used herein is a chemical expression well known to those skilled in the art. This refers to the expression of the amount of a material, compound, or element in moles (mol), and is known to be calculated by dividing the mass (g) by the molar mass (g / mol) of the material, compound, or element. The term "substantially" as used herein will be understood by those skilled in the art and may also include embodiments such as "overall," "completely," "entirely," etc. Therefore, in embodiments, the adjective "substantially" may also be removed. Where applicable, the term "substantially" may also refer to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. The terms heating and cooling are known to those skilled in the art. Heating and cooling can both include or consist of any possible means of heating or cooling a heated mixture. Cooling is preferably in the form of quenching or includes quenching. Quenching is a known term, for example, known according to materials science, and refers to the rapid cooling of a material in a fluid such as water, liquid nitrogen, oil, polymers, other fluids, or in air. Quenching is preferably carried out in a fluid, preferably in water or liquid nitrogen, particularly in water. Generally, quenching prevents potentially undesirable low-temperature processes by reducing the time window during the cooling process. The inventors synthesized a composition with a range of [missing information - likely related to composition range] using two cooling methods. x = 0.0 to 0.5% of bromide, chloride, and iodide-rich lithium-sulfur silver-germanium ore Li 6−x PS 5−x Hal 1+x This involves performing chemical reactions to form more complex molecules from chemical precursors. Cooling methods have been discovered to control the reaction of Li. 6−x PS 5−x Hal 1+x 4 in the series dThe halide structures at the sites are disordered. Rietveld refinement analysis based on X-ray diffraction and neutron diffraction was used to analyze the occupancy of cations and anions and the lithium substructure. With increasing halide content, Li... + Ions are far from the cage center (4d site), such as R 平均值 The higher long-range connectivity between the lithium cage and the average lithium distance is indicated by this. In the case of bromide-rich silver-germanium ore, slow cooling methods cause the ionic conductivity to increase from 0.78 mS / cm. -1 (Li6PS5Br) increased to 6.2 mS cm -1 (Li) 5.5 PS 4.5 Br 1.5 The quenching method shows a value of 3.21 mS cm. -1 (Li6PS5Br) increased to 9.0 mS cm -1 (Li) 5.5 PS 4.5 Br 1.5 These findings demonstrate how chemical changes and synthesis conditions affect structural disorder and lithium substructure to tune the transport properties of these materials. The method of the present invention also demonstrates that it provides a synthesis approach that is faster and more efficient in terms of both time and cost.

[0015] In a fourth aspect, the present invention relates to a product obtained by the methods taught herein, wherein the product is crystalline, particularly a single-phase crystalline material.

[0016] In a fifth aspect, the present invention relates to a power supply system comprising at least one solid-state battery as taught herein.

[0017] This invention provides a solution to one or more of the aforementioned problems and overcomes the shortcomings of the prior art. Furthermore, it provides a very fast synthesis method, typically an order of magnitude faster.

[0018] The advantages of this instruction manual are detailed throughout the manual. Detailed Implementation

[0019] In one exemplary embodiment of the solid electrolyte for solid-state batteries of the present invention, the solid electrolyte is in the form of single-crystal particles, wherein the particles have a size distribution with an average size of 200 nm to 5000 nm, particularly 300 nm to 1000 nm, and wherein, as measured with a Shimadzu SALD-7500nano, the standard deviation of the size distribution is 2% to 20% relative to the average size, particularly 5% to 12% relative to the average size. The phrase 'size distribution with an average size' refers to the manner in which the particle size is generally described. Since describing the average size of particles using a single average value does not provide information about the extent to which the particle size is distributed around the average value and in what direction, the average size is usually used in conjunction with a specific standard deviation to describe the distribution. Those skilled in the art will recognize that, following a specific average value of the size, the width of the size distribution also provides insight into a particular particle size distribution. A suitable method for measuring said particle size distribution is by using a Shimadzu SALD-7500nano instrument with a measurement range of 7 nm to 800 μm, which is a laser diffraction particle size analyzer. In one exemplary embodiment of the solid electrolyte for solid-state batteries of the present invention, the solid electrolyte is a mixed crystal. Single-phase crystalline materials can exist in mixed-phase form. As used herein, the term mixed-phase refers to a crystal comprising two or more elements (also called ions or molecules) that occupy different sites in the crystal lattice. These elements can substitute for each other in the lattice due to their similar molecular structures and shapes.

[0020] In one exemplary embodiment of the solid electrolyte for solid-state batteries of the present invention, at least one of a first combination, a second combination, a third combination, a fourth combination, and a fifth combination is present, particularly two or three of the combinations are present.

[0021] The first combination, second combination, third combination, fourth combination, and fifth combination used herein refer to the combinations described in the first aspect of the present invention, wherein A is selected from Li, Na, and their first combination; wherein Z is selected from P, As, Sb, and their second combination; wherein M is selected from Si, As, Ge, Sn, and Sb, and their third combination; wherein E is selected from O, S, Se, Te, and their fourth combination; and wherein Hal is selected from Cl, Br, I, and their fifth combination.

[0022] In an exemplary embodiment of the solid electrolyte for solid-state batteries of the present invention, the unit cell of the solid electrolyte correspondingly includes a plurality of crystalline Hal sites (Wyckoff 4a), wherein a first Hal site among the crystalline Hal sites is partially occupied by E and Hal, particularly the Wyckoff 4a Hal site and the Wyckoff 4d Hal site, the first Hal site particularly having a crystalline Hal site distribution, particularly the following Hal distribution: wherein the first site is occupied by at most 95%, particularly at most 88%, more particularly at most 60%, even more particularly at most 37%, and wherein the second site is occupied by more than 5%, particularly 12%-80%, more particularly 40%-75%. In materials science, lattice structure is a primary indicator for measuring the structure-property paradigm of crystal structures. Crystalline compounds are understood through the number of various atomic chemical environments associated with Wyckoff sites. In crystallography, Wyckoff sites are conjugate symmetry points. Therefore, features associated with various atomic environments in a crystal can be fed into the input layer of a deep learning model. Methods using Wyckoff sites to analyze crystals can help predict crystal structures. The term crystal site used in this article refers to a site in the crystal lattice, that is, the position of an element (atom, molecule, etc.) within the crystal lattice.

[0023] In one exemplary embodiment of the solid electrolyte for solid-state batteries of the present invention, the solid single-crystal electrolyte has at least 1%-75% site disorder, particularly 15%-70% at least 25%-65% site disorder, such as 30%-55%, particularly two or three site disorders. The term site disorder (also known as crystal disorder) as used herein refers to a co-crystallization of more than one rotational isomer, conformational isomer, or isomer, wherein the centroid of each form is the same. Due to disorder, the crystallographic solution is the sum of all forms. Therefore, disorder, particularly anionic disorder, refers to the random arrangement of various anions within the same crystal site. Due to the periodicity of crystals, each object repeats regularly in three-dimensional space; however, in the case of disorder, the orientation of some atoms differs in different unit cells. The synthesis method developed by the inventors has been found to control disorder in order to further improve the electrolyte of the present invention, which has higher ionic conductivity.

[0024] In an exemplary embodiment of the solid electrolyte for solid-state batteries of the present invention, the solid single-crystal electrolyte has a concentration >1 mScm. -1 Especially >8 mScm -1 Such as 10-50 mScm -1The term ionic conductivity, as used herein, refers to the measure of a substance's tendency to conduct ions. Ion conduction means the movement of ions. In most solids, ions occupy fixed positions rigidly, tightly surrounded by neighboring atoms or ions. In other solids, selected ions have high mobility, thus allowing ionic conduction. Materials such as electrolytes used in batteries do indeed possess this property. Ionic conductivity is expressed in Siemens per meter (S / m) and, depending on the specific value, can therefore also be expressed in millisiemens per unit length (mS / cm), microsiemens per unit length (μS / cm), etc.

[0025] In an exemplary embodiment of the solid electrolyte for solid-state batteries of the present invention, the solid single-crystal electrolyte has a crystallinity of >95%, particularly >98%, such as >99%, and / or wherein the unit cell of the solid single-crystal electrolyte has a plurality of A crystal sites, particularly Wyckoff T2 sites, Wyckoff T4 sites, Wyckoff T5a sites, and Wyckoff T5 sites, wherein at least two of the plurality of A crystal sites are partially or completely occupied by A, particularly three or four A crystal sites, and has a crystal site A distribution, particularly the following A distribution: wherein, as determined by neutron diffraction data, particularly by its Rietveld refinement, the first site is occupied by more than 55%, wherein the second site is occupied by 1%-25%, particularly 10%-20%, wherein the third site is occupied by less than 26%, particularly 0%-10%, and wherein the remaining portion occupied by A is occupied by the fourth site, and / or wherein the solid single-phase crystalline electrolyte has a crystallinity of 0.1 × 10⁻⁶. -10 F cm -2 Up to 20×10 -10 F cm -2 Especially 1×10 -10 F cm -2 Up to 10×10 -10 F cm -2 The capacitance, and / or the solid single-crystal electrolyte having an α value of 0.89–0.97 representing the overall transport, has not yet been observed to have a grain boundary distribution.

[0026] As used in this article, crystallinity refers to the degree of structural order in a solid. In a crystal, atoms and / or molecules are arranged in a regular and periodic manner. Crystallinity can affect properties such as hardness, density, transparency, diffusion, and higher ionic conductivity.

[0027] In one exemplary embodiment of the solid-state battery of the present invention, the cathode material is selected from Fe-containing cathodes, Mn-containing cathodes, Li- or Na-containing cathodes, Co-containing cathodes, transition metal alloys, Ni-containing cathodes, particularly nickel-containing alloys, and more particularly nickel alloys having >75% Ni, such as >80 atomic% Ni, and / or the anode comprises a material selected from alloys, particularly Al alloys, Sn alloys, Mg alloys, Ag alloys, Sb alloys, In alloys, and silicon alloys (a-Si). y A x :Q z The first electrode is selected from B, C, N, Ge, O and combinations thereof, and the second electrode is selected from H, F and combinations thereof. The silicon alloy or the silicon is porous to accommodate electrolyte ions, such as Li ions. The silicon alloy or the silicon has a porosity of 1%-50%. The silicon alloy or the silicon is amorphous, and the silicon or the silicon alloy is preferably hydrogenated. The first electrode is selected from conversion anode materials, particularly metal sulfides, metal oxides, metal phosphides, metal nitrides, metal fluorides and metal selenides, more particularly wherein the metals are transition metals. The second electrode is selected from carbon-based compounds, such as graphite and graphene. The third electrode is selected from Li or Na metal anodes, and / or the at least one first electrode and / or the at least one second electrode comprises nanocrystalline materials.

[0028] As used herein, the term porosity refers to the fraction of voids per unit volume in a particular material such as silicon or silicon alloys; or in other words, the ratio between the total volume of pores and the total volume of the material. Volume fraction is expressed as a percentage. This can generally be readily determined using techniques such as gravimetric analysis. As used herein, the term nanocrystalline material refers to a known class of crystalline materials that are single-phase or multi-phase polycrystalline materials with ultrafine grain sizes in the range of 1 nm to 100 nm.

[0029] In one exemplary embodiment of the solid-state battery of the present invention, the battery further includes at least one separator, wherein the at least one separator is disposed between at least one solid crystalline electrolyte and a first electrode or a second electrode.

[0030] In one exemplary embodiment of the solid-state battery of the present invention, at least one first electrode has a thickness of 50 μm-500 μm, particularly 100 μm-300 μm, such as 150 μm-250 μm, and / or at least one second electrode has a thickness of 20 μm-300 μm, particularly 40 μm-200 μm, such as 50 μm-100 μm, and / or at least one solid crystalline electrolyte has a thickness of 100 μm-1000 μm, particularly 200 μm-800 μm, such as 300 μm-500 μm.

[0031] In one exemplary embodiment of the method for producing solid crystalline electrolytes according to the present invention, the milling time is 10-60 minutes, particularly 20-30 minutes, and / or The grinding process is performed at 500 rpm-600 rpm, especially 505 rpm-520 rpm, and / or During electrolyte formation, pressure is applied for a period of 10-60 seconds, such as 20-40 seconds, particularly 49-500 MPa, especially 100-200 MPa, while the milled mixture is heated to a temperature of 400-550°C, and / or for a period of 5-120 minutes, particularly 20-105 minutes, and / or During the cooling time of 1 second to 30 seconds, the cooling is from the heating temperature to a temperature of 15°C to 30°C.

[0032] In one exemplary embodiment of the method for producing solid crystalline electrolytes according to the present invention, the heating temperature is 300°C-750°C, particularly 400°C-550°C, and / or the heating time is 1 minute-10 minutes, particularly wherein a preheating oven at said heating temperature is used.

[0033] In an exemplary embodiment of the method for producing solid crystalline electrolytes according to the present invention, the precursor is selected according to the following: A is selected from Li, Na and a first combination thereof; Z is selected from P, As, Sb and a second combination thereof; M is selected from Si, Ge, As, Sn and Sb and a third combination thereof; E is selected from O, S, Se, Te and a fourth combination thereof; Hal is selected from Cl, Br, I and a fifth combination thereof, particularly wherein the precursor is selected from Li, P, S, Si, Cl, Br and I and combinations of A, Z, M, E and Hal (especially AHal) and ZE, such as LiHal and P4S. 10 And the condition is that Li2S is not selected.

[0034] The invention will be further illustrated below by way of the following embodiments, which are exemplary and illustrative and are not intended to be construed as limiting the invention. It will be apparent to those skilled in the art that many variations (whether obvious or not) credibly fall within the scope of protection defined in these claims. Attached Figure Description

[0035] Figures 1-10 , Figures 11a-11f and Figure 12 The diagram or representation of the invention and experimental results are shown.

[0036] Attached Figure In the attached diagram: 10 First Electrode 20 Second electrode 30 Solid electrolyte 41 First diaphragm 42 Second diaphragm Figure 1 The schematic solid-state battery shown below comprises a first electrode 10 (typically a Li-containing electrode), a second electrode 20 (typically a composite electrode), optional separators 41, 42 (such as polymer and / or ceramic separators), and an intermediate solid electrolyte. In most cases, no separator is used. The battery provides a voltage V at the + / - electrodes, respectively.

[0037] Figure 2 A schematic perspective view of a solid-state battery is shown below, comprising a first electrode 10 (anode), a second electrode 20 (cathode), and a solid electrolyte 30 in electrical contact with the first and second electrodes. Such solid-state batteries typically have a substantially cylindrical or prismatic shape and a variable width x and height y.

[0038] In view of this disclosure, electrolyte 30 includes at least one solid single-phase crystalline electrolyte, wherein the solid single-phase crystalline electrolyte may include A 6-x ZE 5-x Hal 1+x and A 6+x Z 1-x M 1-x E 5-x Hal 1+x At least one of them, wherein A is selected from Li, Na and their first combination, wherein Z is selected from P, As, Sb and their second combination, wherein M is selected from Si, As, Ge, Sn and Sb and their third combination, wherein E is selected from O, S, Se, Te and their fourth combination, wherein Hal is selected from Cl, Br, I and their fifth combination, and wherein x is <-1; 1.0], especially <-1; 0.75], particularly wherein x is not -0.99 to -1.

[0039] The cathode (second electrode 20) material can be selected from Fe-containing cathodes, Mn-containing cathodes, Li or Na-containing cathodes, Co-containing cathodes, transition metal alloys, Ni-containing cathodes, especially nickel-containing alloys, and even more particularly nickel alloys with >75% Ni, such as >80 atomic% Ni; The material of the anode (first electrode 10) may include or may additionally include materials selected from alloys, particularly Al alloys, Sn alloys, Mg alloys, Ag alloys, Sb alloys, In alloys, and silicon alloys a-Si. y A x :Q z The silicon alloy or silicon, wherein element A is selected from B, C, N, Ge, O and combinations thereof, wherein element Q is selected from H, F and combinations thereof, wherein the silicon alloy or silicon is porous to accommodate electrolyte ions, such as Li ions, wherein the silicon alloy or silicon has a porosity of 1%-50%, wherein the silicon alloy or silicon is amorphous, and wherein the silicon or silicon alloy is preferably hydrogenated; selected from conversion anode materials, particularly metal sulfides, metal oxides, metal phosphides, metal nitrides, metal fluorides and metal selenides, more particularly wherein the metals thereon are transition metals; selected from carbon-based compounds, such as graphite and graphene; and selected from Li or Na metal anodes.

[0040] The first electrode 10 and / or the second electrode 20 may include or may additionally include nanocrystalline materials.

[0041] In solid-state batteries, the electrolyte can act as a separator between the anode and cathode. However, solid-state batteries may also include at least one separator. Optional additional separators are not included. Figure 2 As shown in the text, but Figure 1 The solid-state battery is shown in the schematic diagram (41, 42). At least one of these optional separators is disposed between the electrolyte 30 and the first electrode 10 or the second electrode 20.

[0042] The first electrode 10 preferably has a thickness of 50 μm-500 μm, particularly 100 μm-300 μm, such as 150 μm-250 μm.

[0043] The second electrode 20 preferably has a thickness of 20 μm-300 μm, particularly 40 μm-200 μm, such as 50 μm-100 μm.

[0044] Electrolyte 30 preferably has a thickness of 100 μm-1000 μm, particularly 200 μm-800 μm, such as 300 μm-500 μm.

[0045] Figure 3A schematic representation of the crystal structure of argentite-germanium sulfide Li6PS5X is shown. In this particular embodiment, the crystal structure of Li6PS5Br is shown in an anionic ordered state, wherein Br − Located at the Wyckoff 4a site, while the sulfide anion (S... 2− The halogen ions are located at the Wyckoff 4d site. The crystal structure is shown as an ordered structure with space group F-43m; the halide ions are arranged in a face-centered cubic lattice (Wyckoff position 4a), where PS4 is located at the Wyckoff 4d site. 3− The polyhedron is located in the octahedral void (P is located on Wyckoff 4b, while S is located on Wyckoff 16e), and S is "free". 2− (Not bound in the polyhedron) Located at the half-tetrahedral site Wyckoff 4d. Li + A cage-like arrangement is formed around the 4d site. In this particular embodiment, the letters y and z represent partial substitution in the lattice structure: y indicates that S partially substitutes for Se, while z indicates that P is partially substituted by Si, Ge, Sn, or As.

[0046] Figure 4 The table shows the occupancy of various Li sites in the sulfosilver-germanium series as a function of bromide content, using quenching and slow cooling methods. The three bars on the left (0, 0.3, and 0.5) represent quenching as the cooling method, and the three bars on the right (0, 0.3, and 0.5) represent slow cooling as the cooling method.

[0047] Figure 5 This indicates the ionic conductivity as a function of site disorder %. Measurements were performed at room temperature and with Br... − / S 2− This relates to an exemplary electrolyte of Li6PS5Br with disordered sites. Figure 5 The text indicates that Br is... − / S 2− The room-temperature conductivity obtained as a function of site disorder. It is clearly shown that an increase in disorder leads to an increase in ionic conductivity, i.e., an increase.

[0048] Figure 6 This indicates the site disorder in lithium-sulfur silver-germanium ore as a function of Br content % under both cooling methods. As determined by Rietveld refinement of the neutron diffraction pattern, the slowly cooled sample (Li6PS5Br) exhibits lower site disorder. For the slow cooling method, site disorder increases with increasing total Br content. x = 0.0 starts at 12% and in xAt x = 0.5, the site disorder reaches 63%. The quenching method has even higher site disorder, starting at 39% at x = 0.0 and increasing to 72% at x = 0.5, which is likely because rapid cooling “freezes” the higher site disorder achieved at higher temperatures.

[0049] Figure 7 Each component (Li) is shown 6−x PS 5−x Br 1+x The percentage of Br content and total Br content at Wyckoff 4a sites, which is a function of x.

[0050] Figure 8 This demonstrates an exemplary electrolyte Li synthesized under different pressures (MPa) according to the method of the present invention. 5.5 PS 4.5 Cl 1.5 The XRD patterns are shown. The electrolytes were synthesized at 98 MPa, 245 MPa, and 490 MPa, respectively. Lines 1-3 at the bottom represent the electrolyte synthesized at 98 MPa, line 4 (Example 4) represents the electrolyte synthesized at 245 MPa, and lines 5 and 6 at the top represent the electrolyte synthesized at 490 MPa. The different examples relate to different methods used to produce the specific electrolytes. First, a manual press was used at different pressures, followed by a heating step at 500°C for 15 minutes.

[0051] Example 1 shows the XRD patterns of the initial precursors Li2S, P2S5, and LiCl.

[0052] Example 2 shows the XRD patterns of Li2S, P2S5, and LiCl samples that have undergone three cycles (15 minutes) of ball milling (BM).

[0053] Example 3 shows the XRD patterns of the BM precursor after three cycles (15 minutes), with the powder manually pressed. For the first three examples, pellets were formed using a manual press at 98 MPa, followed by heating at 500°C for 15 minutes to form crystalline Li. 5.5 PS 4.5 Cl 1.5 .

[0054] Example 4 shows the XRD pattern of the BM precursor after 3 cycles (15 minutes), with powder pressing performed manually. For Example 4, pellets were formed using a manual press at 245 MPa, followed by heating at 500°C for 15 minutes to form crystalline Li. 5.5 PS 4.5 Cl 1.5 .

[0055] Example 5 shows the XRD pattern of the BM precursor after 3 cycles (15 minutes), with powder pressing performed manually. For Example 5, pellets were formed using a manual press at 490 MPa, followed by heating at 500°C for 15 minutes to form crystalline Li. 5.5 PS 4.5 Cl 1.5 .

[0056] Example 6 shows a repetition of Example 5.

[0057] This indicates that as the pressure used during the synthesis process increases, the intensity (count) of the XRD spectrum increases accordingly.

[0058] Figure 9 This demonstrates the ionic conductivity as a function of the applied pressure in the synthesis method of the present invention.

[0059] Figure 9 Reference numbers 3, 4, 5 and 6 in the text refer to Figure 8 Examples 3, 4, 5, and 6 are described in the illustration. Example 3 was synthesized at a pressure of 98 MPa, Example 4 at 245 MPa, and Examples 5 and 6 at 490 MPa.

[0060] In this particular embodiment, the embodiment relates to Li 5.5 PS 4.5 Cl 1.5 Electrolytes, which are synthesized at 98 MPa, 245 MPa or 490 MPa respectively.

[0061] For specific examples 3, 4, 5, and 6 synthesized at pressures of 98 MPa, 245 MPa, 450 MPa, and 450 MPa, respectively, the resulting ionic conductivity is as follows: Pressure (MPa) Ionic conductivity (mS / cm) 98 8.58 245 10.7 450 10.8 450 11.2 This indicates that when the electrolyte is synthesized at 245 MPa or 490 MPa, the resulting electrolyte has a much higher ionic conductivity than the electrolyte synthesized at 98 MPa.

[0062] Figure 10 This indicates that the general electrolyte Li 6-x PS 5-x Br 1+xThe ionic conductivity as a function of x was measured. The ionic conductivity of electrolytes where x was 0, 0.3, or 0.5 was determined. It is clearly shown that the measured ionic conductivity increases accordingly as the value of x increases from 0 to 0.5. Furthermore, it was found that the results vary depending on the specific cooling method applied: either a slow cooling process or a process involving quenching was used. In both cases, the ionic conductivity increases as x increases from 0 to 0.3 to 0.5. This further indicates that the ionic conductivity induced by quenching is higher for a particular electrolyte than that synthesized using a method involving slow cooling.

[0063] Figures 11a-11c The Li prepared according to this method is shown. 5.5 PS 4.5 Cl 1.5 SEM images of particle size (milled for 10-25 minutes, heated to 400-500℃ for about 5 minutes, followed by quenching); and Figures 11d-11f This illustrates Li prepared according to existing technology. 5.5 PS 4.5 Cl 1.5 SEM images of the particle size (milled for about 10 minutes and heated to 450°C-550°C for about 7 days). The particle size according to the invention is 200 nm to 2000 nm, while the particle size of the prior art is about 5 μm to about 100 μm, thus at least an order of magnitude larger.

[0064] Figure 12 The results of pulsed-field gradient NMR measurements are shown. This indicates that the diffusivity of Li ions in the unit cell is enhanced. The diffusion coefficient increases from 1.27 × 10⁻⁶. -12 m 2 / s (Li6PS5Br, slow cooling, symbol below) increased to 1.01×10^ -12 m 2 / s(Li 5.5 PS 4.5 Br 1.5 Quenching, symbol above).

[0065] experiment In this study, the substitution of halides (Li) was investigated. 6−x PS 5−x Br 1+x Li 6−x PS 5−x Cl 1+x Li6S x Si 1-x S 5-x I 1+xThe influence of x on lithium-sulfur silver-germanium ore (within the range of 0.0 ≤ x ≤ 0.5) was investigated; structural disorder was also designed by changing the synthesis scheme. Furthermore, this method was also used to synthesize halide-mixed lithium-sulfur silver-germanium ore (Li... 6−x PS 5−x Hal 1+x Hal = Cl, Br, I, Cl y Br 1-y and Cl 0.33 Br 0.33 I 0.33 (within the range of 0.0 ≤ x ≤ 0.5). Similar experiments were performed with Na replacing Li, As and Sb replacing P respectively, and O replacing S. Experiments with Se and Te replacing S have been planned. For the second structural argillium-germanium ore A... 6+x Z 1-x M 1- x E 5-x Hal 1+x Similar results were obtained for A=Li or Na, the aforementioned halides, and for Z=P and E=S. Experiments replacing S with Se and Te have been planned. The obtained structural disorder was also found in the second-structured silver-germanium sulfide.

[0066] First, a precursor of silver-germanium sulfide was prepared by mechanical milling, followed by heat treatment at a specific temperature to obtain crystalline silver-germanium sulfide. Two different cooling methods were employed to influence the structural disorder. Rietveld refinement of the neutron diffraction pattern indicates that this preparation method affects the structural disorder. Further analysis using Hal... − (Hal = Cl, Br, or I) Replace S 2− The high ionic conductivity was found to be related to 4 d The presence of less negative charge at the site is associated with the identification of additional T4 Li in halide-based argentite-germanium ore. + Loci. Results provide ~8-12 (e.g., 9) mS / cm. -1 The increased ionic conductivity.

[0067] Mechanochemical milling and post-annealing: Li was subjected to a process under an argon atmosphere. 6−x PS 5−x Br 1+x To prevent contamination by oxygen (O2 < 2 ppm) and water (H2O < 1 ppm), Li was synthesized using a mechanochemical milling process (Fritsch Pulverisette 7 premiumline). 6−x PS 5−x Hal 1+x (Hal = Cl, Br, I, Cl) y Br 1-y and Cl 0.33 Br0.33 I 0.33 Initial precursors: lithium sulfide (Li₂S, 99.98%) or Li and S of the same 99.98% purity, lithium bromide (LiBr, 99.99%), and phosphorus pentasulfide (P₄S). 10 The precursors (99%) were purchased from Merck and Sigma-Aldrich. All precursors were mixed in appropriate (or close) stoichiometric ratios using a mortar and pestle. Then, 1.0 g, 5 g, and 10 g of the obtained precursors were mechanically and chemically milled at 450 rpm–600 rpm (e.g., 510 rpm) for 10–30 minutes using zirconia balls with diameters of 3 mm, 5 mm, and 10 mm. The resulting powder was manually pressed into pellets with diameters of 0.8 cm, 1 cm, and 1.5 cm and then placed in quartz ampoules. The quartz ampoules were then placed under vacuum (<10 °C). -3 Seal under mbar. Place the sealed quartz ampoule in a furnace for crystallization, and for Li 6−x PS 5−x Br 1+x Composition, at 450℃-550℃ (for x =0.0) and preheated the furnace at 430℃. After a reaction time of 10-15 minutes, two different cooling methods were applied: (1) quenching in liquid water for rapid cooling. (2) slow cooling for 4 days using a cooling rate of 4 K / h. The final powder was obtained, then manually ground and stored in an argon atmosphere glove box. The phase purity, lithium substructure and ion transport of the silver-germanium sulfide series were analyzed by X-ray diffraction, neutron powder diffraction and electrochemical impedance spectroscopy.

[0068] X-ray diffraction: X-ray diffraction was performed using XˈPert Pro X-ray diffraction (PaNalytical) in Bragg-Brenta θ-θ geometry under Cu K radiation (l1 = 1.540598 Å and l2 = 1.544426 Å, at 45 kV and 40 mA) to determine phase purity and related structural parameters. Measurements were performed in the 2θ range between 10° and 90°. All powders were placed on an airtight sample holder with a Kapton cap under an argon atmosphere to prevent exposure to air.

[0069] Neutron Powder Diffraction: Neutron powder diffraction data were collected at room temperature using a PEARL neutron powder diffractometer at the TU Delft research reactor, with reflections from a germanium monochromator at 533 Å (neutron wavelength λ = 1.667 Å).

[0070] Electrochemical impedance spectroscopy: Temperature-dependent electrochemical impedance spectroscopy was performed using an Autolab EC10M impedance analyzer at an amplitude of 0.01V and a frequency range of 10 MHz to 1 Hz to determine the ionic conductivity of the samples.

[0071] Rietveld refinement: Rietveld refinement was performed on the X-ray diffraction and neutron diffraction data using TOPAS software. Early structural information of Li6PS5Br obtained by neutron powder diffraction was used as the starting point for this study. Goodness-of-fit (GOF) and R² values ​​were used as the fitting indices. wp Determine the quality of the fit. Refine the following parameters: (1) use the 15 coefficients of the Chebyshev function to fit the background and model the peak shape by the modified Thomson-Cox-Hasting pseudo-Voigt function; (2) scale factor, zero error; (3) lattice parameters, isotropic atomic displacement parameters; (4) free S 2− (Wyckoff 4) d ) and Hal − (Wyckoff 4) a The atomic occupancy of the anions, because the two anions are exchangeable. Assume Wyckoff 4 a Site, Wyckoff 4 d The site was completely destroyed by S 2− and Hal − Occupied, then Hal at these sites − and S 2− The occupancy rate is limited to one (Hal − (4) a )+ S 2− (4) a The occupancy rate of S is 1. 2− (4) d )+ Hal − (4) d The lithium occupancy rate was set to 1). The stability of the refinement was ensured by simultaneously refining multiple relevant parameters. Finally, the lithium occupancy rate at potential interstitial sites was identified using a Fourier difference map (FDM).

[0072] From a crystallographic perspective, Se, Te, and O can replace S at the Wyckoff positions mentioned above; I and Cl can replace Br; Na can replace Li; and As and Sb can replace P.

[0073] result Structural changes induced by Br content and synthesis method: Hal −Lithium-sulfur silver-germanium ore Li6PS5Hal represents Cl, Br, or I in Hal − With S 2− The structures exhibit structural disorder between positions, with larger disorder leading to faster Li-ion transport. Recently, it was found that the structural disorder in the single-component Li6PS5Br can be modulated via synthetic methods. Furthermore, it has been shown that Br... − Replace S 2− Increase ionic conductivity. A series of Li-based synthesis methods were used to synthesize Li... 6−x PS 5−x Br 1+x The materials (x ≤ 0.5), as previously reported, were mechanically milled to ensure homogeneous mixing, followed by heating at different temperatures (550 °C for x = 0.0 or 430 °C for x = 0.3 and 0.5) for 10–15 minutes, sufficient to achieve crystallization of lithium-sulfur silver-germanium ore. To control site disorder (in this case, 4...), d (Br occupancy rate at the site), two different cooling methods were applied: (1) cooling the material at a rate of 4 °C / hour for several days to minimize the Br occupancy rate in each component. d Br occupancy rate at the site; (2) Quenching the material in liquid water (rapid cooling) to achieve 4 d Higher Br occupancy at the site. Quenching is expected to "freeze" the 4-phase synthesis achieved at higher (synthesis) temperatures. d Higher Br occupancy rate at the site.

[0074] The sample contained a small amount of impurity phase less than 1.0 wt.%, the effect of which was negligible on ion transport or structural analysis. The cubic polymorphism was maintained when the contents of Br and Cl, as well as the mixture of Cl, Br, and I, increased to x = 0.5. Analysis focused on the cubic polymorphism within the solubility limit (x ≤ 0.5).

[0075] The Pawley fit refinement of the lattice parameter a = 9.98356 (7) for slowly cooled Li6PS5Br. It was found that the lattice parameter decreased with increasing Br content (higher x) and increased with rapid cooling.

[0076] The lattice parameters as a function of Br distributed at Wyckoff 4a sites were investigated. For the slow-cooling method, it was found that increasing the Br content had an effect on the lattice parameters at the 4a sites. a The Br occupancy rate at the sites was not significantly affected. Therefore, the decrease in lattice parameters with increasing Br content may be attributed to Li. + Vacancy increase and / or Li + Distribution differences. In the quenched sample, the lattice parameters are different from those of 4. aThere is a clear trend in Br occupancy rates at the sites. As Br content increases, 4 a The Br occupancy rate in the sites also increases, resulting in larger lattice parameters.

[0077] 4 in a single composition d The Br occupancy at the sites can be adjusted by modifying the synthesis method. With increasing Br content (x), Br is distributed at the Wyckoff 4a and 4d sites in the crystal structure. The Br occupancy as a function of the total Br content was investigated using two different cooling methods to obtain 4a and 4d sites. d The percentage of Br at the site. Determined by Rietveld refinement of the neutron diffraction pattern, the slowly cooled sample was selected as 4. d The lowest Br occupancy rate at the site. For the slow cooling method, as the total Br content increases, 4 d Br also increases at the site, x = 0.0 starts at 12% and in x = 0.5, reaching 63%. Quenching methods have even higher 4 d Br at the site, x = 0.0, starting from 39% to x = 0.5 at 72%, because rapid cooling "freezes" the temperature at higher temperatures, achieving 4. d Higher Br at the site.

[0078] Lithium substructure: As mentioned above, in the lithium-sulfur silver-germanium ore structure, the anionic framework creates six different types of tetrahedral interstices, five of which can accommodate lithium. Based on the adjacent PS4 3− The number of corners, edges, or faces shared by the units classifies these tetrahedra, and these tetrahedra are designated as type 1 through type 5 (T1–T5). The discovery of Li... + Occupying type 5 and type 2 (T5, T2, and T5a) positions, such as in Li6PS5Hal (Hal = Cl, Br, and I), thus surrounding the central anion (Wyckoff 4). d This forms a cage-like structure. Furthermore, Li... + It can partially occupy the T4 site (Wyckoff 16). e ), such as in Li 6.15 Al 0.15 Si 1.35 S 5.4 O 0.6In the Li₂S-SnS₂-SiS₂-P₂S₅ sulfides, the room-temperature high-symmetry m-structure of Li₆PS₅Br was used as the starting model. The occupancy of various Li sites in the silver-steresite series, obtained using quenching and slow cooling methods, varied with bromide content. Rietveld refinement revealed four Li⁺ sites occupied to varying degrees, the degree of which was within the Li⁺ range. 6− x PS 5−x Br 1+x The composition may vary in different forms: T5, T2, T5a, and T4. It was found that under refined Br content conditions, the total Li... + The content is limited to achieve charge balance. For x = 0.0−0.5 composition (quenching and slow cooling), the refined thermal displacement parameter of the T2 site compared to other Li in the structure + The site is relatively large (for the T2 site, B) iso The value is ~9 Å 2 This indicates that Li around the T2 site + The delocalization of localized motion. For slow cooling x = 0.0 composition, the refined thermal displacement parameter of the T4 site is negative, and FDM does not show visible evidence of Li occupation at the T4 site. Additional T4 lithium sites are found when the Br content in the slowly cooled composition increases to x ≥ 0.3. These sites are stably refined, and excluding them from the model leads to a poor fit. For example, when in x When the ratio is 0.3, excluding the T4 site will cause R... wp It increased from 6.4% to 7.0%.

[0079] It was found that the volumes of polyhedra T2, T5, and T4 were almost unaffected by changes in Br content. Li 6−x PS 5−x Br 1+xThe BVSE landscape showed that the intercage Li+ diffusion pathways were more interconnected at higher Br contents. The T2−T2 and T5−T4−T5 distances as a function of bromide content were investigated for both slow cooling and quenching methods. The slowly cooled Li6PS5Br composition allowed only lithium ion diffusion via the T2−T2 pathway, with no occupancy of the T4 site observed. With increasing bromine content, the T2−T2 distance remained constant for the slow cooling method and decreased for the quenching method. In both synthesis methods, the T5−T4−T5 distance decreased with increasing bromide content. In the slow cooling method, the T5−T4−T5 distance decreased from 3.76 (10) Å at x = 0.3 (composition) to 3.6 (9) Å at x = 0.5 with increasing bromide content. In the quenching method, the T5−T4−T5 distance decreased from 3.64(12) Å at x = 0.0 to 3.49(8) Å at x = 0.5. In summary, with increasing bromide content, the T5−T4−T5 cage distance decreased for both slow cooling and quenching cooling, and only for quenching cooling did the T2−T2 cage distance decrease, which may promote long-range diffusion, especially for quenched materials.

[0080] Wyckoff 4 a and 4 d The average charge at a site can vary based on its occupancy rate, which is attributed to Br − and S 2− The charge difference. In order to quantify Br − How does it affect the arrangement? Calculate 4 d Site (central anion, S) 2− ) and Li located at different sites (T2, T5, and T5a) + The average distance between them, weighted by the occupancy rate of each site within a single cage, as previously described. This is accompanied by a series of variations in total Br content and 4... d Br occupancy rate at the site, observed R 平均值 The significant deviation. This result is obtained from Li 6−x PS 5−x Br 1+x room temperature 6 Supported by Li NMR spectra. With 4 d The spectrum of Li6PS5Br with lower Br occupancy at the sites showed a strong resonance at 1.615 ppm, which was assigned to Li occupying the T2, T5, and T5a sites. + Atoms. The inventors observed that as Br... − Increased content 6The Li resonance has shifted to higher fields and lower ppm values. This shift to lower ppm values ​​indicates that Li atoms are experiencing a more electron-rich environment. With 4 d Br at the site − The amount increases, each through an increase in Br content, because divalent sulfides are replaced by monovalent Br, 4 d The average negative charge at the site decreased. To examine the changes in total Br content and Br₄… d Market share for Li 6−x PS 5− x Br 1+x To investigate the effect of ionic conductivity, temperature-dependent impedance spectroscopy was performed to measure ionic conductivity and activation energy. Impedance data at lower temperatures (-40°C to 25°C) were fitted using a resistor and a parallel constant-phase element (CPE). The parallel CPE correspondingly exhibited an impedance of approximately 1 × 10⁻⁶. -10 F cm -2 Up to 8×10 -10 F cm -2 The capacitance and α value indicating overall transport are 0.89–0.97. Ionic conductivity at room temperature varies with Br content. For both cooling methods, ionic conductivity increases with Br content. As shown, higher site disorder (in this case 4) is observed. d The Br occupancy rate at the 4d site increases the ionic conductivity. The conductivity of the slowly cooled Li6PS5Br sample (12% Br occupancy at the 4d site) is 0.78 mS / cm. -1 The conductivity of the slowly cooled sample increased from 0.78 mS / cm with increasing Br content. -1 Increased to 6.2 mS cm -1 The conductivity of the quenched sample decreased from 3.21 mS / cm with increasing Br content. -1 Increased to 8.55 mS cm -1 .

[0081] Structure-property relationship: Increased by 4 by changing the synthesis method d The Br occupancy rate at the site can significantly improve the ionic conductivity in lithium-sulfur silver-germanium ore. The inventors were able to adjust the Br occupancy rate in each composition. d Br occupancy and lithium substructure at the site. Some observations are as follows: • For slow cooling methods, the Br occupancy at the 4d site increases with increasing total Br content, starting at 12% and reaching 63%. At higher temperatures, 4 d The Br occupancy rate in the site is higher, and quenching can be "frozen" 4 kinetically. d Higher Br occupancy at the sites. The quenching method was found to have even higher 4...d The Br occupancy rate at the sites ranged from 39% to 72%. Overall, this study highlights the synthetic method as a tool for controlling Br occupancy in lithium-sulfur silver-germanium ores. d The importance of Br occupancy rate at the site.

[0082] • A non-zero T4 occupancy was found in the lithium substructure.

[0083] • In both cooling methods, with 4 d The Br occupancy rate at the site increases (see above section) because divalent sulfides are replaced by monovalent bromide ions, 4 d The average negative charge at the site decreases. This results in a higher overall conductivity.

[0084] • For samples cooled slowly, the inventors found that the ionic conductivity decreased from 0.78 mS / cm. -1 Increased to 6.20 mScm -1 .

[0085] For the quenched samples, the ionic conductivity was found to be 3.21 mS / cm. -1 Increased to 8.55 mS cm -1 .

[0086] Higher halide concentration The method of the present invention is used to prepare small-grain-size glass-ceramic Li5PS4Cl 2, The synthesis of Li5PS4Br2 and Li5PS4I2 was carried out, and the glass ceramics exhibited ionic conductivity of 1.0 mS / cm, 2.75 mS / cm and 8.23 ​​mS / cm, respectively.

[0087] List of possible anodes and cathodes for possible applications: anode: ► Alloy anodes (such as aluminum (Al), tin (Sn), magnesium (Mg), silver (Ag), antimony (Sb) and their alloys).

[0088] ► Conversion anode materials include transition metal sulfides, oxides, phosphides, nitrides, fluorides, and selenides.

[0089] ► Silicon-based compounds ► Carbon-based compounds ► Li / Na metal anode cathode: ► LiFePO4 ► LiFe x Mn 1-x PO4 ► LiMn2O4 spinel ► LiNi 0.5 Mn 1.5 O4 Spinel ► LiNi x Co y Mn 1−x−y O2 layered oxides ► Li-rich layered oxides The experimental results also referenced a paper entitled "Exploring the Relationship Between Halide Substitution, Structural Disorder, and Lithium Distribution in Lithium Argyrodites Li 6-x PS 5-x Br 1+x The article that has been submitted for publication, and its contents are incorporated by reference.

Claims

1. An electrolyte for solid-state batteries, characterized in that, The electrolyte includes At least one solid single-crystal electrolyte, wherein the solid single-crystal electrolyte is selected from at least one of A6-xZE5-xHal1+x and A6+xZ1-xM1-xE5-xHal1+x, wherein A is selected from Li, Na and a first combination thereof, wherein Z is selected from P, As, Sb and a second combination thereof, wherein M is selected from Si, As, Ge, Sn and Sb and a third combination thereof, wherein E is selected from O, S, Se, Te and a fourth combination thereof, wherein Hal is selected from Cl, Br, I and a fifth combination thereof, and wherein x is <-1; 1.0], particularly <-1; 0.75], especially wherein x is not -0.99 to -1.

2. The solid electrolyte according to claim 1, characterized in that, The solid electrolyte is in the form of single-crystal particles, wherein the particles have a size distribution with an average size of 200 nm to 5000 nm, particularly 300 nm to 1000 nm, and wherein, as measured with a Shimadzu SALD-7500nano, the standard deviation of the size distribution is 2% to 20% relative to the average size, particularly 5% to 12% relative to the average size.

3. The solid electrolyte according to any one of claims 1 to 2, characterized in that, The solid electrolyte is a mixed crystal.

4. The solid electrolyte according to claim 3, characterized in that, The combination includes at least one of the first combination, the second combination, the third combination, the fourth combination, and the fifth combination, and in particular, it includes two or three of the combinations.

5. The solid electrolyte according to any one of claims 1 to 4, characterized in that, The unit cell of the solid electrolyte accordingly includes a plurality of crystalline Hal sites, wherein the first Hal site among the crystalline Hal sites is partially occupied by E and Hal, particularly the Wyckoff 4a Hal site and the Wyckoff 4d Hal site, the first Hal site particularly having a crystalline Hal site distribution, particularly the following Hal distribution: wherein the first site is occupied by at most 95%, particularly at most 88%, more particularly at most 60%, even more particularly at most 37%, and wherein the second site is occupied by more than 5%, particularly 12%-80%, more particularly 40%-75%.

6. The solid electrolyte according to any one of claims 1 to 5, characterized in that, The solid single-crystal electrolyte has at least one site disorder of 1%-75%, particularly at least one site disorder of 15%-70%, more particularly at least one site disorder of 25%-65%, such as 30%-55%, particularly two or three site disorder.

7. The solid electrolyte according to any one of claims 1 to 6, characterized in that, The solid single-crystal electrolyte described therein has an ionic conductivity of >1 mScm-1, particularly >8 mScm-1, such as 10-50 mScm-1.

8. The solid electrolyte according to any one of claims 1 to 7, wherein the solid single-crystal electrolyte has a crystallinity of >95%, particularly >98%, such as >99%, and / or The unit cell of the solid single-crystal electrolyte has a plurality of A crystal sites, particularly Wyckoff T2, Wyckoff T4, Wyckoff T5a, and Wyckoff T5 sites, wherein at least two of the plurality of A crystal sites are partially or completely occupied by A, particularly three or four A crystal sites, and have a crystal site A distribution, particularly the following A distribution: wherein, as determined by neutron diffraction data, particularly by its Rietveld refinement, the first site is occupied by more than 55%, the second site is occupied by 1%-25%, particularly 10%-20%, the third site is occupied by less than 26%, particularly 0%-10%, and the remaining portion occupied by A is occupied by the fourth site, and / or The solid single-crystal electrolyte has a capacitance of 0.1 × 10⁻¹⁰ F cm⁻² to 20 × 10⁻¹⁰ F cm⁻², particularly 1 × 10⁻¹⁰ F cm⁻² to 10 × 10⁻¹⁰ F cm⁻², and / or The solid single-crystal electrolyte has an α value of 0.89–0.97, representing the overall transport.

9. A solid-state battery, characterized in that, The solid-state battery includes At least one first electrode, At least one second electrode, At least one solid single-crystal electrolyte according to any one of claims 1 to 8, wherein the solid single-crystal electrolyte is located between the first electrode and the second electrode and is in contact with the first electrode and the second electrode.

10. The solid-state battery according to claim 9, characterized in that, The cathode material is selected from Fe-containing cathodes, Mn-containing cathodes, Li or Na-containing cathodes, Co-containing cathodes, transition metal alloys, Ni-containing cathodes, especially nickel alloys, and even more particularly nickel alloys with >75% Ni, such as >80 atomic% Ni, and / or The anode comprises materials selected from alloys, particularly Al alloys, Sn alloys, Mg alloys, Ag alloys, Sb alloys, In alloys, and silicon alloys (a-SiyAx:Qz) and silicon, wherein element A is selected from B, C, N, Ge, O and combinations thereof, wherein element Q is selected from H, F and combinations thereof, wherein the silicon alloy or the silicon is porous to accommodate electrolyte ions, such as Li ions, wherein the silicon alloy or the silicon has a porosity of 1%-50%, wherein the silicon alloy or the silicon is amorphous, and wherein the silicon or the silicon alloy is preferably hydrogenated; selected from conversion anode materials, particularly metal sulfides, metal oxides, metal phosphides, metal nitrides, metal fluorides and metal selenides, more particularly wherein the metals thereon are transition metals; selected from carbon-based compounds, such as graphite and graphene; and selected from Li or Na metal anodes.

11. The solid-state battery according to any one of claims 9 to 10, characterized in that, The at least one first electrode and / or the at least one second electrode comprises a nanocrystalline material.

12. The solid-state battery according to any one of claims 9 to 11, characterized in that, The battery further includes at least one separator, wherein the at least one separator is disposed between the at least one solid crystalline electrolyte and the first electrode or the second electrode.

13. The solid-state battery according to any one of claims 9 to 12, characterized in that, The at least one first electrode has a thickness of 50 μm-500 μm, particularly 100 μm-300 μm, such as 150 μm-250 μm, and / or the at least one second electrode has a thickness of 20 μm-300 μm, particularly 40 μm-200 μm, such as 50 μm-100 μm, and / or The at least one solid crystalline electrolyte has a thickness of 100 μm-1000 μm, particularly 200 μm-800 μm, such as 300 μm-500 μm.

14. A method for producing solid crystalline electrolytes, characterized in that, The solid electrolyte to be produced comprises at least one of A6-xZE5-xHal1+x and A6+xZ1-xM1-xE5-xHal1+x, wherein A is selected from Li, Na and a first combination thereof, wherein Z is selected from P, As, Sb and a second combination thereof, wherein M is selected from Si, Ge, As, Sn and Sb and a third combination thereof, wherein E is selected from O, S, Se, Te and a fourth combination thereof, wherein Hal is selected from Cl, Br, I and a fifth combination thereof, and wherein x is <-1; 1.0], particularly <-1; 0.75], especially wherein x is not -0.99 to -1. The precursor is provided in substantially molar amounts and a mixture thereof is formed, wherein the precursor is selected from combinations of A, M, Z, E, ZE and AHal, particularly wherein E is provided in excess of 1.01-1.2 times the stated molar amount. The mixture is milled during the milling time, thereby obtaining a milled mixture. The milled mixture is heated at high temperature during the heating time, thereby forming an electrolyte, and Cooling the heated mixture yields a solid crystalline electrolyte.

15. The method according to claim 14, characterized in that, The grinding time is 10-60 minutes, particularly 20-30 minutes, and / or The grinding process is performed at 500 rpm-600 rpm, especially 505 rpm-520 rpm, and / or Pellets may be formed optionally under pressure, particularly at 49 MPa-500 MPa, especially at 100 MPa-200 MPa, for a pressure time of 10-60 seconds, such as 20-40 seconds. The milled mixture is heated to a temperature of 400°C-550°C, and / or during a heating time of 5 minutes-120 minutes, and / or During the cooling time of 1 second to 30 seconds, the cooling is from the heating temperature to a temperature of 15°C to 30°C.

16. The method according to any one of claims 14 to 15, characterized in that, The heating temperature is 300°C-750°C, particularly 400°C-550°C, and / or the heating time is 1 minute-10 minutes, particularly wherein a preheated oven at the heating temperature is used.

17. The method according to any one of claims 14 to 16, characterized in that, The precursor is selected based on the following: A is selected from Li, Na, and their first combination. Z is selected from P, As, Sb, and their second combination. M is selected from Si, Ge, Sn, and Sb, as well as their third combination. E is selected from S, Se, Te, and their fourth combination. Hal is selected from Cl, Br, I and their fifth combination. Specifically, the precursors are selected from Li, P, S, Si, Cl, Br and I, as well as combinations of A, Z, M, E and Hal (especially AHal) and ZE, such as LiHal and P4S10, with the condition that Li2S is not selected.

18. A product obtained by the method according to any one of claims 14 to 17, characterized in that, The product described therein is crystalline, particularly monocrystalline.

19. A power supply system, characterized in that, The power supply system includes at least one solid-state battery according to any one of claims 9 to 13 and / or at least one product according to claim 18.

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