Solid material particles powder of formula LiaPSbXc(I)

Abstract

The present disclosure relates to a compound of formula (I): Li a P.S. b X c (I) (wherein, -X represents at least one halogen element, -a represents a number between 2.0 and 7.0, -b represents a number between 3.0 and 6.0, and -c represents a number between 0 and 3.0), wherein the solid material particles have a diameter of d less than 50 μm. 50 and characterized in that the L* value in the L*a*b* color system is less than 60.0. The present disclosure also relates to a method for the preparation of such a powder and to the use of such a powder, in particular for producing a solid electrolyte or battery article.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED PATENT APPLICATIONS This patent application claims priority to European Patent Application No. 21306437.1, filed October 14, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure provides a compound of formula (I): Li a P.S. b X c (I) (In the formula, - X represents at least one halogen element; - a is a number between 2.0 and 7.0, - b is a number between 3.0 and 6.0, - c represents a number between 0 and 3.0) A powder of solid material particles comprising: d less than 70μm 50 having a value The L* value in the L*a*b* color system is less than 60.0. Concerning solid material particle powders.

[0003] The present disclosure also relates to methods for the preparation of such powders and in particular to the use of such powders for producing solid electrolyte or battery articles. [Background technology]

[0004] Lithium-ion batteries are widely used, especially as power sources for consumer electronics. In such secondary batteries, organic solvents are used as organic liquid electrolytes, and lithium ions migrate from one electrode to the other depending on whether the battery is being charged or discharged.

[0005] All-solid-state lithium-ion batteries, which do not use organic solvents, are very attractive because the solvents used as electrolytes are flammable. Such all-solid-state lithium-ion batteries are formed by solidifying the entire battery using all-solid components, i.e., the cathode, the anode, and the electrolyte. Since all components of an all-solid-state battery, including the electrolyte, are solid, the all-solid-state battery has a higher electrical resistance and a lower output current compared to batteries using liquid electrolytes. This means that an electrolyte with high electrical conductivity and the ability to maintain this high conductivity over time is required.

[0006] European Patent Application Publication No. 3026749A1 (Mitsui) discloses a cubic crystal structure belonging to the space group F-43m and having the composition formula: Li 7-x P.S. 6-x Ha x (Ha is Cl or Br, and x varies in the range of 0.2 to 1.8), and the value of lightness L* in the L*a*b* color system is 60.0 or more, preferably 70.0 or more, and more preferably 75.0 or more. In this document, the amount of sulfur in the solid electrolyte is correlated with the L* value of said electrolyte in the L*a*b* color system. More precisely, it is believed that sulfur defects in the solid electrolyte lead to a decrease in lightness and should be avoided for performance purposes. In other words, the higher the L* value, the better the electrical conductivity is considered to be.

[0007] However, the inventors have determined that such products, which have high L* values ​​in the L*a*b* color system, tend to be very difficult to use in making composite layers for separators and catholytes.

[0008] It is an object of the present invention to provide a powder of solid material particles that can be conveniently used to make composite layers for separators and electrolytes while retaining high electrical conductivity. Another object of the present invention is to provide a powder that has aging resistance, such as the ability to maintain high electrical conductivity over time. Summary of the Invention

[0009] The present invention relates to a compound of formula (I): Li a P.S. b X c (I) (In the formula, - X represents at least one halogen element; - a is a number between 2.0 and 7.0, - b is a number between 3.0 and 6.0, - c represents a number between 0 and 3.0) A powder of solid material particles comprising: d less than 70μm 50 having a value The L* value in the L*a*b* color system is less than 60.0. Concerning solid material particle powders.

[0010] In some embodiments, the solid material has formula (II): Li 7-x P.S. 6-x X x (II) (In the formula, X represents at least one halogen element selected from the group consisting of F, Cl, Br and I, or a combination thereof; - x represents a positive number between 0.5 and 2.0. Follow.

[0011] The solid material is preferably Li6PS5Cl, Li4P2S6, Li7PS6, Li7P3S 11 Or Li3PS4.

[0012] The present invention relates to a method for producing the powder of the present invention, a) Using a mixing means, preferably mixing beads (preferably made of ceramic), to mix at least 7×10 5Mixing the starting material (M) with a carbon-based solvent (S), preferably selected from aprotic linear hydrocarbons and aromatic hydrocarbons, by using the energy of rotation to obtain a paste in a slurry state; b) drying the paste from step a) to obtain a dry paste; b') optionally pressing the dried paste from step b) into pellets; c) heating the dried paste, for example in the form of pellets, to a temperature comprised between 350° C. and 580° C. for a period of at least 2 hours, for example at least 4 hours, at least 6 hours, at least 8 hours, at least 10 hours or at least 12 hours, The present invention also relates to a method comprising the steps of:

[0013] The present invention also relates to the use of the powder of the present invention for producing a solid electrolyte, a solid electrolyte comprising at least such a powder, an electrochemical device comprising at least such a solid electrolyte, a solid-state battery comprising at least such a solid electrolyte, and an electrode or a battery separator comprising at least such a powder. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In this application: - any description, even if made in relation to a particular embodiment, is applicable and interchangeable with other embodiments of the invention; - when an element or component is said to be included in and / or selected from a list of enumerated elements or components, in the relevant embodiments expressly contemplated herein, it is to be understood that the element or component may be any one of the individual enumerated elements or components, or may also be selected from a group consisting of any two or more of the explicitly enumerated elements or components, and that any element or component enumerated in a list of elements or components may be omitted from such list; - Any recitation herein of numerical ranges by endpoints includes all numbers subsumed within the recited range, as well as the endpoints of the range and equivalents thereof.

[0015] The present invention relates to a compound of formula (I): Li a P.S. b X c (I) (In the formula, - X represents at least one halogen element; - a represents a number from 2.0 to 7.0, for example, a number from 3.0 to 6.0, 4.0 to 6.0, or 5.0 to 6.0; - b represents a number from 3.0 to 5.0, for example, a number from 3.5 to 5.0 or 3.9 to 5.0; - c represents a number from 0 to 3.0, for example, from about 0.9 to about 2.9, or from about 1.0 to about 2.5, or even from about 1.0 to about 2.0. A powder of solid material particles comprising: d less than 50μm 50 having a value The L* value in the L*a*b* color system is less than 60.0. Concerning solid material particle powders.

[0016] The inventors have surprisingly found that such products, having an L* value in the L*a*b* color system of less than 60.0, are well suited for use in slurries in making composite layers, particularly for separator layers and catholyte layers.

[0017] Without being bound to any particular theory, it is believed that powders exhibiting an L* value of less than 60.0 exhibit a hydrophobicity that is well suited to mixing with the solvent used to create the composite layer. On the other hand, although it is impossible to characterize the hydrophobicity of such materials, since, according to the inventors' findings, it is not possible to identify a solvent that does not interact with the surface of the material, for example when performing contact angle measurements, the inventors believe that a direct correlation can be obtained between the L* value of a powder and its hydrophobicity. Thus, the hydrophobicity of a material can be indirectly evaluated by measuring the L* value of the material in the L*a*b* color system. Contrary to the teachings of the prior art, the powders of the present invention actually exhibit a lower L* value in the L*a*b* color system than those of the prior art.

[0018] It has also been found that the hydrophobicity of the powder has a positive effect on the resistance of the powder to aging over time: again, without being bound by any particular theory, it is believed that the more hydrophobic the powder, the less water it will absorb (water has been found to be particularly detrimental to sulfide powders over time) and the less susceptible the powder will be to aging.

[0019] Powders of solid material particles exhibiting such low L* values ​​can be prepared by wet mechanochemistry, particularly using selected carbon-based solvents in combination with specific amounts of energy. The use of such carbon-based solvents during the powder preparation process results in specific carbon species at the surface of the powder.

[0020] Although it is generally accepted that carbon residues can adversely affect ionic conductivity (decreased by grain boundaries) and electronic conductivity (which can be increased at higher carbon contents), the inventors have found that the presence of carbon residues on the surface of the powder actually provides an improved compromise between the material's conductivity, resistance to aging, and its convenience for use in the preparation of electrolyte composite layers, making the material of the present invention highly suitable for use in the manufacture of all-solid-state lithium-ion batteries.

[0021] Therefore, the powder of the present invention is characterized by an L* value in the L*a*b* color system of less than 60.0, preferably less than 59.0, more preferably less than 58.0, and even more preferably less than 56.0.

[0022] As described more precisely in the examples, the L* value can in particular be measured using an X-Rite Ci52 spectrophotometer operated by the software OnColor. The instrument is calibrated with a white standard (L*a*b=95.82 -0.60 2.15) and a black trap before carrying out the measurements on the sulfides. A thin layer of the powder to be analyzed is placed in a sample holder with a quartz window to ensure the stability of the sample during the measurements.

[0023] The powder of the invention can also be characterized by a C content comprised between 0.4 and 2.5% by weight, for example between 0.5 and 2.0% by weight or between 0.6 and 1.9% by weight.

[0024] According to formula (I), c may be zero. In this case, the solid material does not include any halogen components and the solid material has formula (I'): Li a P.S. b (I') (In the formula, a is a number between 2.0 and 7.0, for example, between 3.0 and 7.0; - b represents a number from 3.0 to 5.0, for example, a number from 3.9 to 4.9 or 4.0 to 4.5 Follow.

[0025] According to formula (I), c may be 0.9 to 1.1. In this case, the solid material has the formula (I″): Li a P.S. b X c’ (I'') (In the formula, - c' represents a number between 0.9 and 1.1, e.g., equal to 1.0) may be in accordance with the following.

[0026] According to this formula (I″), X is preferably Cl. In this case, formula (I″) is as follows: Li a P.S. b Cl c’ (I'').

[0027] In some embodiments, the solid material has formula (II): Li 7-x P.S. 6-x X x (II) (In the formula, X represents at least one halogen element selected from the group consisting of F, Cl, Br and I or a combination thereof; - x represents a positive number between 0.5 and 2.0. Follow.

[0028] According to these embodiments, x may more specifically range from 0.8 to 1.8, for example, x may be 1.0 or 1.5, x may range from 0.95 to 1.05, or from 1.45 to 1.55, and / or X may more specifically be Cl, Br, or a combination thereof, and X may more specifically be Cl.

[0029] In some preferred embodiments, the solid material is Li6PS5Cl, Li4P2S6, Li7PS6, Li7P3S 11 or Li3PS4, more preferably Li6PS5Cl or Li3PS4.

[0030] The composition of the solid materials described in this disclosure may be determined according to well-known analytical techniques.

[0031] In the present invention, the solid material characterized by the formula, here formula (I) or (II), may be the main component of the powder, the proportion of which may be at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, or even at least 98% or 99% by weight, based on the total weight of the powder.

[0032] The powders may also include, for example, an amorphous phase, and starting materials used to prepare the powder, such as LiX (wherein X is a halogen, such as Cl), Li2S, phosphorus sulfide (eg, P2S5), and / or Li3PO4.

[0033] The powders are also characterized by their size or particle size distribution (PSD). The size of the particles of the powders, as measured by laser diffraction in paraxylene, is: - d less than 70 μm, e.g. less than 65 μm, less than 50 μm, or less than 40 μm 50 value, - d > 0.05μm 10 Value, and / or - d less than 100 μm, for example less than 90 μm, less than 80 μm, or less than 70 μm 90 value It may be that.

[0034] Preferably, d 50 Values ​​range from 2 μm to less than 70 μm as measured by laser diffraction in paraxylene.

[0035] The powder may be composed of agglomerated particles.

[0036] d 50 -value corresponds to the median of the distribution of particle diameter values. Measurements of particle size distribution (PSD), e.g. d 50 -value, d 10 -value, and d 90 The -value can be carried out on a number of particles, at least 150, using a scanning electron microscope (SEM), or by laser diffraction in paraxylene.

[0037] The particles of the powder may be spherical in shape.

[0038] The particles of the powder may exhibit a sphericity SR of 0.8 to 1.0, more specifically 0.85 to 1.0, even more specifically 0.90 to 1.0. SR may preferably be 0.90 to 1.0 or 0.95 to 1.0. The sphericity of a particle is calculated from the measured circumference P and the projected area A of the particle using the following formula: SR=4πA / P 2 .

[0039] For an ideal sphere, SR is 1.0, and for spherical particles it is less than 1.0. SR can be determined by dynamic image analysis (DIA). Examples of devices that can be used to perform DIA are Retsch's CAMSIZER® P4 or Sympatec's QicPic®. More specifically, sphericity can be measured according to ISO 13322-2 (2006). DIA generally requires the analysis of a statistically meaningful large number of particles (e.g., at least 500 or even at least 1000).

[0040] The crystalline phase of the powder (corresponding to a cubic structure belonging to the space group F-43m) can be characterized by X-ray diffraction (XRD) using a Cu radiation source.

[0041] The powder may advantageously exhibit an ionic conductivity of at least 1.5 mS / cm, such as at least 1.7 mS / cm, or from 1.9 to 5.0 mS / cm, such as from 2.0 to 4.5 mS / cm, as measured in a compressed (500 MPa) pellet by impedance spectroscopy.

[0042] The measurement of ionic conductivity is carried out on pressed pellets. Typically, pressed pellets are produced using uniaxial or isostatic pressure. When pellets are formed by applying uniaxial pressure, a pressure of more than 100 MPa, advantageously more than 300 MPa, is applied for a time of at least 30 seconds. Measurements are typically carried out under uniaxial pressures of 2 MPa to 200 MPa at room temperature and subsequently converted to values ​​at 30°C.

[0043] The powders of the invention can also be characterized by their resistance to aging, measured in particular by the change in electrical conductivity and weight over time.

[0044] The invention also relates to powders obtained by a process involving wet mechanochemistry using a carbon-based solvent.

[0045] The present invention relates to a) Using a mixing means, preferably mixing beads (e.g. ceramic), to mix at least 7×10 5 Mixing the starting material (M) with a carbon-based solvent (S), preferably selected from aliphatic hydrocarbons (e.g., heptane) and aromatic hydrocarbons (e.g., xylene), by the energy of rotation to obtain a paste in the form of a slurry; b) drying the paste from step a) to obtain a dry paste; b') optionally pressing the dried paste from step b) into pellets; c) heating the dried paste, for example in the form of pellets, to a temperature comprised between 350° C. and 580° C. for a period of at least 2 hours, for example at least 4 hours, at least 6 hours, at least 8 hours, at least 10 hours or at least 12 hours, The present invention also relates to such a method for producing the above-mentioned powder, comprising:

[0046] The starting materials (M) are preferably at least lithium sulfide (Li2S) and phosphorus sulfide.

[0047] The carbon-based solvent (S) is preferably selected from among aliphatic hydrocarbons (such as hexane, heptane, octane or nonane, preferably heptane) and aromatic hydrocarbons (such as benzene, toluene, ethylbenzene, xylene or liquid naphthenes, preferably xylene). More preferably, the carbon-based solvent (S) is selected from the group consisting of xylene, paraxylene, heptane, octane and mixtures thereof.

[0048] In some embodiments, the starting materials for step a) are at least lithium sulfide (LiS) and phosphorus sulfide.

[0049] In step a), the starting materials (M), such as Li2S, LiCl, and P2S5, are mixed together. These starting materials are generally in powder form to obtain a homogeneous mixture. The amounts of these starting materials are defined to obtain the targeted stoichiometric ratio. A small excess of Li2S can be used, especially to compensate for possible losses of S during calcination. The excess Li2S can be added, for example, up to 10% by weight relative to the targeted stoichiometric ratio.

[0050] Step a) is conveniently carried out by wet ball milling the starting material (M) in a carbon-based solvent (S).

[0051] The weight ratio "solvent (S) / mixture (M+S)" may be from 0.2 to 3.0, for example, from 0.4 to 2.0 or from 0.5 to 1.5.

[0052] The duration of mixing, for example milling, may be from 1 to 130 hours, for example preferably from 3 to 70 hours or from 6 to 40 hours.

[0053] The step a) of obtaining a paste in a slurry state is carried out by adding at least 7×10 5 Rotation, e.g., at least 7.1 x 10 per liter of mixture (M+S) 5 Rotations / L, at least 7.5 x 10 5 Rotation, at least 8.0 x 10 5 rev / L, or at least 8.5 x 10 5 This is done with rotational energy.

[0054] According to step b), the paste from step a) is dried. Drying can be conveniently carried out by evaporation of the liquid hydrocarbon. The evaporation of the liquid hydrocarbon is preferably carried out at a temperature between 100° C. and 150° C., more particularly between 105° C. and 135° C. The evaporation can be carried out under vacuum. The duration of the evaporation is generally between 1 and 20 hours, more particularly between 2 and 20 hours or between 3 and 7 hours.

[0055] In step c), the mixture of step b) is heated (or calcined), for example in a rotary oven, at a temperature between 350°C and 580°C, for example between 370°C and 550°C, or between 390°C and 530°C. Step c) is preferably carried out under an inert atmosphere, for example under an atmosphere of N2 or Ar or H2S. The duration of step c) is between 1 and 12 hours, more specifically between 2 and 10 hours, or between 3 and 7 hours. During step c), the crystallinity of the mixture is improved, and as a result, the electrical conductivity is improved.

[0056] The rotary oven that can be used to sinter the dried paste from step b) or the pellets from step b') can rotate at a rotation speed of 0.5 to 10.0 rpm. The size of the granules can be varied by varying the speed. The higher the rotation speed, the larger the size of the particles. This also means that the higher the rotation speed, the higher the yield of the composition exhibiting the target size.

[0057] The process may include an additional step d) of sieving the granules to select a particular size range. This operation can be performed manually or automatically. In laboratory conditions, it is advantageously performed manually.

[0058] The present invention also relates to various end uses of the powders described herein.

[0059] The powders of the present invention can be used to prepare solid electrolytes.

[0060] The present invention also provides a solid electrolyte comprising at least the powder described herein; - an electrochemical device comprising at least the solid electrolyte described herein, - a solid-state battery comprising at least the solid electrolyte described herein; an electrode comprising at least a metal substrate; at least one layer directly adhered to said metal substrate, (i) a powder of the present invention; (ii) at least one electroactive compound (EAC); (iii) optionally at least one lithium ion conducting material (LiCM) other than the solid-state material of the present invention; (iv) optionally, at least one electrically conductive material (ECM); (v) optionally a lithium salt (LIS); (vi) optionally, at least one layer made from a composition comprising at least one polymeric binder material (P); and A separator comprising at least a powder according to the invention; optionally at least one polymeric binding material (P), optionally at least one metal salt, in particular a lithium salt, - optionally, at least one plasticizer; Includes.

[0061] To the extent that the disclosures of any patents, patent applications, and publications incorporated herein by reference conflict with the statements of this application to the extent that a term may be unclear, this statement shall control. EXAMPLES

[0062] The present disclosure will now be described in more detail with reference to the following examples, the purpose of which is merely illustrative and is not intended to limit the scope of the present disclosure.

[0063] material Inventive Material #1 The material of the present invention, Li6PS5Cl, can be obtained by the following process.

[0064] In the first step, 15.8 g LiCl (Sigma-Aldrich, purity >99%), 41.4 g P2S5 (Sigma-Aldrich, purity >99%) and 42.5 g Li2Sigma-Aldrich) were added to a 500 mL zirconia bottle containing ZrO2 balls (10 mm). Then, 100.5 g paraxylene (Sigma-Aldrich, purity >99%, dry) was added. The clamped bottle was quickly sealed to prevent evaporation of the solvent. Wet ball milling was performed using a planetary ball mill. Milling was performed at 500 rpm for 21 h, which was approximately 3.8 × 10 per liter of starting material and solvent mixture. 6 This corresponds to the energy of rotation. A slurry paste is obtained.

[0065] In the second step, the paste was transferred into a dry alumina crucible and dried in an oven under dynamic vacuum at 130° C. to remove the solvent. After 5 hours of drying, the milling balls were separated from the dried powder by a 4 mm sieve.

[0066] In the third step, the dried mixture was placed in an alumina crucible under argon atmosphere (containing less than 10 ppm water). The crucible was then inserted into a tube furnace and the product was crystallized at a temperature above 400° C. for 12 hours under flowing N2 (20 L / h). The oven was then cooled before the crucible was retrieved.

[0067] The final product was in the form of a polydisperse powder with several agglomerates of different sizes. The finished product was obtained by dry homogenization.

[0068] Inventive Material #2 In the first step, 19.7 g LiCl (Sigma-Aldrich, purity >99%), 51.7 g P2S5 (Sigma-Aldrich, purity >99%) and 53.4 g Li2Sigma-Aldrich) were added to a zirconia bottle containing ZrO2 balls (10 mm). Then, 125 g paraxylene (Sigma-Aldrich, purity >99%, dry) was added. The clamped bottle was quickly sealed to prevent evaporation of the solvent. Wet ball milling was performed using a planetary ball mill. The milling was performed at 290 rpm for 65 hours. The energy consumed to prepare the slurry paste was approximately 6.8 × 10 per liter of starting material and solvent mixture. 6 It was a rotation.

[0069] In the second step, the paste was transferred into a dry alumina crucible and dried in an oven under dynamic vacuum at 130° C. to remove the solvent. After 5 hours of drying, the mill grinding balls were separated from the dried powder through a 4 mm sieve.

[0070] In the third step, the dried mixture was placed in an alumina crucible under argon atmosphere (containing less than 10 ppm water). The crucible was then inserted into a tube furnace and crystallized at a temperature above 400° C. for 12 hours under flowing N2 (20 L / h). The oven was then cooled before the crucible was retrieved.

[0071] The final product was in the form of a polydisperse powder with several agglomerates of different sizes. The finished product was obtained by dry homogenization.

[0072] Inventive Material #3 In the first step, 16.2 g LiCl; 52.9 g P2S5, 33.1 g LiBr, and 41.6 g Li2S were added to a zirconia bottle containing ZrO2 balls (10 mm). Then, 129.4 g xylene was added. The clamped bottle was quickly sealed to prevent evaporation of the solvent. Wet ball milling was carried out using a planetary ball mill. The milling was carried out at 350 rpm for 15 hours. The energy consumed to prepare the slurry paste was approximately 1.9×10 per liter of starting material and solvent mixture. 6 It was a rotation.

[0073] In the second step, the paste was transferred to a dry round-bottom flask and dried under dynamic vacuum in a rotary evaporator at 60° C. to remove the solvent. After 3 h of drying, the mill grinding balls were separated from the dried powder through a 4 mm sieve.

[0074] In the third step, the dried mixture was placed in an alumina crucible under argon atmosphere (containing less than 10 ppm water). The crucible was then inserted into a tube furnace and crystallized at 500° C. for 6 h under flowing N2 (20 L / h). Afterwards, the oven was cooled and the crucible was retrieved.

[0075] The final product was in the form of a polydisperse powder with several agglomerates of different sizes. The finished product was obtained by dry homogenization.

[0076] Inventive Material #4 In the first step, 14.7 g LiCl; 25.7 g P2S5, and 21.2 g Li2S were added to a zirconia bottle containing ZrO2 balls (10 mm). Then, 123 g xylene was added. The clamped bottle was quickly sealed to prevent evaporation of the solvent. Wet ball milling was carried out using a planetary ball mill. The milling was carried out at 350 rpm for 15 hours. The energy consumed to prepare the slurry paste was approximately 1.9×10 per liter of starting material and solvent mixture. 6 It was a rotation.

[0077] In the second step, the paste was transferred to a dry round-bottom flask and dried under dynamic vacuum in a rotary evaporator at 60° C. to remove the solvent. After 3 h of drying, the mill grinding balls were separated from the dried powder through a 4 mm sieve.

[0078] In the third step, the dried mixture was placed in a dry silicon carbide crucible covered with a papyex sheet under an argon atmosphere (containing less than 10 ppm water). The crucible was then inserted into a tube furnace and crystallized at 520°C for 12 hours under flowing N2 (20 L / h). The oven was then cooled before the crucible was retrieved.

[0079] The final product was in the form of a polydisperse powder with several agglomerates of different sizes. The finished product was obtained by dry homogenization.

[0080] Inventive Material #5 In the first step, 6.2 g LiCl; 16.3 g P2S5, and 16.8 g Li2S were added to a zirconia bottle containing ZrO2 balls (10 mm). Then, 91 g xylene was added. The clamped bottle was quickly sealed to prevent evaporation of the solvent. Wet ball milling was carried out using a planetary ball mill. The milling was carried out at 300 rpm for 8 hours. The energy consumed to prepare the slurry paste was approximately 8.6×10 per liter of starting material and solvent mixture. 5 It was a rotation.

[0081] In the second step, the paste was transferred to a dry round-bottom flask and dried under dynamic vacuum in a rotary evaporator at 60° C. to remove the solvent. After 3 h of drying, the mill grinding balls were separated from the dried powder through a 4 mm sieve.

[0082] In the third step, the dried mixture was placed in an alumina crucible under argon atmosphere (containing less than 10 ppm water). The crucible was then inserted into a tube furnace and crystallized at 510° C. for 6 h under flowing N2 (20 L / h). Afterwards, the oven was cooled and the crucible was retrieved.

[0083] The final product was in the form of a polydisperse powder with several agglomerates of different sizes. The finished product was obtained by dry homogenization.

[0084] Comparative material #A In the first step, 22.7 g LiCl (Sigma-Aldrich, purity >99%), 59.5 g P2S5 (Sigma-Aldrich, 20 purity >99%) and 61.5 g Li2S were added to a zirconia jar containing ZrO2 balls (10 mm). Then, 130 g paraxylene (Sigma-Aldrich, purity >99%, dry) was added. The clamped jar was quickly sealed to prevent evaporation of the solvent. Wet ball milling was performed using a planetary ball mill. 5 × 10 per liter of mixture was added. 5 After milling for 7 hours at 200 rpm, which corresponds to a rotation of 7 × 10 per liter 5 Rotation was smaller than that of the previous step, resulting in a slurry paste.

[0085] Such materials have an L* value in the L*a*b* color system of greater than 60.0 and were not suitable for use as materials for solid-state batteries with expected performance characteristics.

[0086] Comparative material #B The standard material Li6PS5Cl was obtained by the following steps.

[0087] In the first step, 0.631 g LiCl (purity >99%); 1.655 g P2S5 (purity >99%), and 1.713 g Li2S (purity >99%) were added to a 45 mL zirconia bottle containing 5 mm ZrO2 balls. Ball milling was performed using a planetary ball mill. After milling at 500 rpm for 2 h, a mixed powder was obtained.

[0088] In a second step, the powder was homogenized in a mortar in an Ar-filled glove box (<1 ppm H2O, <1 ppm O2) and then pelletized at 500 MPa to produce 6 mm diameter pellets with masses ranging from 300 to 500 mg. These pellets were sealed under vacuum in a carbon-lined quartz tube. The product was crystallized at 550 °C for 7 h with a heating and cooling rate of 0.5 °C / min.

[0089] The final product was in the form of dense pellets. The finished product was obtained by dry homogenization using a mortar in an Ar-filled glove box.

[0090] Test Method L* value in the L*a*b* color system The L values ​​are measured using an X-Rite Ci52 spectrophotometer operated by the software OnColor. The instrument is calibrated by a white standard (L*a*b=95.82 -0.60 2.15) and a black trap before carrying out the measurements on the sulfides. A thin layer of the powder to be analyzed is placed in a sample holder with a quartz window to ensure the stability of the sample during the measurements.

[0091] PSD The PSD of the dispersion is measured on a Malvern Mastersizer 3000 by laser diffraction using paraxylene.

[0092] Conductivity and electrochemical impedance spectroscopy (EIS) Prior to impedance spectroscopy measurements, the powder samples were cold pressed at 500 MPa in an Ar-filled glove box. Electrical conductivity was acquired on pellets made using a uniaxial press operating at 500 MPa. Pelletization was performed using a laboratory-scale uniaxial press in a moisture-free argon-filled glove box. Two carbon paper foils (Papyex soft graphite N998 Ref: 496300120050000 from Mersen, thickness 0.2 mm) are used as current collectors. The pellets with their carbon electrodes are then packed in an airtight sample holder and a pressure of 40 MPa is applied on the sample holder for the measurements. Impedance spectra are acquired on a Biologic VMP3 device. The samples are placed in a Binder thermostat and impedance measurements are performed at different temperatures. Each spectrum is acquired after 2 hours of stabilization at the target temperature. The temperature range is from -20°C to 60°C in 10°C increments. Impedance spectroscopy is acquired in PEIS mode, with an amplitude of 20 mV, and frequencies ranging from 1 MHz to 1 kHz (25 points per decade, average of 50 measurements per frequency point).

[0093] result PSD results Inventive Material #1 · d 10 Value = 27μm · d 50 Value = 61μm · d 90 Value = 107μm

[0094] Inventive Material #2 · d 10 Value = 4μm · d 50 Value = 16μm · d 90 Value = 43μm

[0095] Inventive Material #3 · d 10 - Value = 7μm · d 50 - Value = 26μm · d 90 - Value = 62μm

[0096] Inventive Material #4 · d 10 - Value = 8μm · d 50 - Value = 22μm · d 90 - Value = 50 μm

[0097] Inventive Material #5 · d 10 - Value = 3μm · d 50 - Value = 10μm · d 90 - Value = 48μm

[0098] Comparison Material #B · d 10 - Value = 7μm · d 50 - Value = 27μm · d 90 - Value = 103μm

[0099] [Table 1]

Claims

1. Formula (I): Li ａ PS ｂ X ｃ (I) (In the formula, X represents at least one halogen element; a represents a number from 2.0 to 7.0; b represents a number from 3.0 to 6.0; c represents a number from 0 to 3.0) A powder of solid material particles of d in the range of 2 μm to less than 70 μm as measured by laser diffraction using paraxylene ５０ has a value, The L* value in the L*a*b* color system is less than 60.

0. powder.

2. The solid material has the formula (II): Li ７－ｘ PS ６－ｘ 8 ｘ (99) (In the formula, X represents at least one halogen element selected from the group consisting of F, Cl, Br and I, or a combination thereof; x represents a positive number between 0.5 and 2.

0.

2. The powder according to claim 1,

3. The solid material is Li ６ P.S. ５ Cl, Li ４ P ２ S ６ , Li ７ P.S. ６ , Li ７ P ３ S １１ or Li ３ P.S. ４ 3. The powder according to claim 1 or 2, wherein

4. When measured by laser diffraction in paraxylene, d less than 50 μm ５０ value, d greater than 0.05 μm １０ value, and / or d less than 100 μm ９０ value 3. The powder according to claim 1 or 2, wherein

5. 3. Powder according to claim 1 or 2, exhibiting an ionic conductivity of at least 1.5 mS / cm as measured in a compressed (500 MPa) pellet by impedance spectroscopy.

6. 3. The powder according to claim 1 or 2, obtained by a process comprising wet mechanochemistry using a carbon-based solvent.

7. The method comprises: a) Using a mixing means, preferably mixing beads, to mix at least 7 x 10 per liter of mixture (M+S) ５ Mixing the starting material (M) with a carbon-based solvent (S), preferably selected from aliphatic and aromatic hydrocarbons, by using rotational energy to obtain a paste in a slurry state; b) drying the paste from step a) to obtain a dry paste; b') optionally pressing the dried paste from step b) into pellets; c) heating the dried paste, e.g., in the form of pellets, to a temperature of 350°C to 580°C for at least 2 hours; 7. The powder of claim 6, comprising:

8. The starting material (M) is at least lithium sulfide (Li ２ 8. The powder of claim 7, wherein the metal is selected from the group consisting of phosphate, phosphate ...

9. 7. The powder of claim 6, wherein the solvent is selected from the group consisting of p-xylene, heptane, octane, and mixtures thereof.

10. Formula (I): Li ａ PS ｂ X ｃ (I) (In the formula, X represents at least one halogen element; a represents a number from 2.0 to 7.0; b represents a number from 3.0 to 6.0; c represents a number from 0 to 3.0) A powder of solid material particles of d less than 50 μm ５０ has a value, The L* value in the L*a*b* color system is less than 60.

0.

1. A method for producing a powder of solid material particles, comprising: The method comprises: a) Using a mixing means, preferably mixing beads, to mix at least 7.0 x 10 per liter of mixture (M + S). ５ Mixing the starting material (M) with a carbon-based solvent (S), preferably selected from aliphatic and aromatic hydrocarbons, by using rotational energy to obtain a paste in a slurry state; b) drying the paste from step a) to obtain a dry paste; b') optionally pressing the dried paste from step b) into pellets; c) heating the dried paste, e.g., in the form of pellets, to a temperature of 350°C to 580°C for at least 2 hours; A method comprising:

11. 3. Use of the powder according to claim 1 or 2 for producing a solid electrolyte.

12. A solid electrolyte comprising at least the powder according to claim 1 or 2.

13. A solid-state battery comprising at least the solid electrolyte of claim 12.

14. at least, A metal substrate; at least one layer directly adhered to the metal substrate, (i) a powder according to claim 1 or 2; (ii) at least one electroactive compound (EAC); and (iii) optionally at least one lithium ion conducting material (LiCM) other than the solid state material of the present invention; (iv) optionally at least one electrically conductive material (ECM); (v) optionally a lithium salt (LIS); and (vi) optionally at least one polymeric binder material (P); and An electrode comprising:

15. at least, The powder according to claim 1 or 2, Optionally, at least one polymeric binder material (P), optionally at least one metal salt, in particular a lithium salt, optionally, at least one plasticizer; Contains separators.