Solid electrolyte member and method for manufacturing solid electrolyte member

Abstract

To suppress deterioration of battery performance.SOLUTION: The solid electrolyte member is provided which includes Li, P, and S, and in which the total contained amount of Li measured by ICP emission spectrometry method is, on the basis of mass, 8.1 mass% or more and 17.9 mass% or less for the total contained amount of elements included in the solid electrolyte member, the total contained amount of Al, Zr, Ti, Si, and W measured by fluorescent X-ray spectrometry method is, on the basis of mass, less than 100 ppm for the total contained amount of elements contained in the solid electrolyte member, and, when the solid electrolyte member is classified to have a particle size of less than 5 μm, a particle size of 5 μm or more and less than 100 μm, and a particle size of 100 μm or more, the total contained amount of Al, Zr, Ti, Si, and W measured by fluorescent X-ray spectrometry method is, on the basis of mass, less than 100 ppm for the total contained amount of elements contained in the solid electrolyte member in each of the classified solid electrolyte members.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a solid electrolyte member and a method for manufacturing the solid electrolyte member.

Background Art

[0002] As a solid electrolyte for lithium batteries, sulfide-based solid electrolytes are known. Patent Document 1 describes a sulfide solid electrolyte material composed of glass ceramics composed of an ion conductor having lithium, phosphorus, and sulfur and lithium halide, which contains at least one of Al2O3, ZrO3, TiO2, and SiO2. Patent Document 2 describes a solid electrolyte containing aluminum in an amount of 100 ppm or more and 1000 ppm or less on a mass basis and having lithium ion conductivity.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] A solid electrolyte member having lithium, phosphorus, and sulfur is required to suppress deterioration of battery performance.

[0005] The present invention has been made in view of the above, and an object thereof is to provide a solid electrolyte member and a method for manufacturing the solid electrolyte member capable of suppressing deterioration of battery performance.

Means for Solving the Problems

[0006] The present invention provides a solid electrolyte member and a method for manufacturing the solid electrolyte member, which are characterized by satisfying the following conditions.

[0007] <1> A solid electrolyte member containing Li, P, and S, wherein the content of Li measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) is 8.1% by mass or more and 17.9% by mass or less based on the total content of elements contained in the solid electrolyte member, and the total content of Al, Zr, Ti, Si, and W measured by X-ray fluorescence spectroscopy (XRF) is less than 100 ppm based on the total content of elements contained in the solid electrolyte member. When the solid electrolyte member is classified into particles with a particle size of less than 5 μm, particles with a particle size of 5 μm or more and less than 100 μm, and particles with a particle size of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, Si, and W measured by X-ray fluorescence spectroscopy is less than 100 ppm based on the total content of elements contained in the solid electrolyte member.

[0008] <2> A solid electrolyte member containing Li, Si, P, and S, wherein the content of Li measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) is 8.1% by mass or more and 17.9% by mass or less based on the total content of elements contained in the solid electrolyte member, and the total content of Al, Zr, Ti, and W measured by X-ray fluorescence spectroscopy (XRF) is less than 100 ppm based on the total content of elements contained in the solid electrolyte member. When the solid electrolyte member is classified into particles with a particle size of less than 5 μm, particles with a particle size of 5 μm or more and less than 100 μm, and particles with a particle size of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, and W measured by X-ray fluorescence spectroscopy is less than 100 ppm based on the total content of elements contained in the solid electrolyte member.

[0009] <3>A solid electrolyte member preferably having an average crystallite diameter of 50 nm or more and a conductivity of 4 mS / cm or more.

[0010] <4>Preferably, it has a crystal structure of space group P42nmc. When measured by X-ray diffraction measurement using CuKα rays, peaks of the following formulas (A) to (E) are detected as crystal peaks, and a peak of formula (F) is not detected on the higher angle side than the peak of formula (D), or the diffraction intensity of the peak of formula (E) is I A and the diffraction intensity of the peak of formula (F) is I B In the case of, I B / I A A solid electrolyte member in which the peak of formula (F) is detected such that it is less than 0.50. 2θ = 17.38° ± 0.50° ··· (A) 2θ = 20.18° ± 0.50° ··· (B) 2θ = 20.44° ± 0.50° ··· (C) 2θ = 26.96° ± 0.50° ··· (D) 2θ = 29.58° ± 0.50° ··· (E) 2θ = 27.33° ± 0.50° ··· (F)

[0011] <5>A solid electrolyte member preferably having an Argyrodite-type crystal structure.

[0012] <6>A method for manufacturing a solid electrolyte member according to the present disclosure, including a preparation step of preparing an aggregate of raw materials for the method of manufacturing the solid electrolyte member, and a generation step of heating the aggregate of the starting raw materials to generate the solid electrolyte member, wherein in the preparation step, the starting raw materials are mixed so that crystal peaks of crystalline substances can be detected when the generated aggregate of the starting raw materials is measured by X-ray diffraction method to generate the aggregate of the starting raw materials. A method for manufacturing a solid electrolyte member.

Advantages of the Invention

[0013] According to the present invention, deterioration of battery performance can be suppressed.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0015] Hereinafter, the present invention will be described in detail with reference to the drawings. It should be noted that the present invention is not limited by the following embodiments for carrying out the invention (hereinafter referred to as embodiments). In addition, the constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art, substantially the same ones, and those within the so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be combined as appropriate.

[0016] (First Embodiment) (Solid Electrolyte Member) The solid electrolyte member according to the first embodiment is a sulfide-based solid electrolyte. The solid electrolyte member according to the first embodiment is a lithium ion conductor containing Li, P, and S, and is used, for example, in a lithium battery or the like. Furthermore, the solid electrolyte member according to the first embodiment has a so-called LGPS-type crystal structure. Specifically, the solid electrolyte member according to the first embodiment has a chemical formula of Li a M b P c S d where a, b, c, and d are numbers greater than 0. Also, the element M is at least one element of Group 13, Group 14, and Group 15 excluding Al and Si. In the present embodiment, the element M is preferably at least one of Ge and Sn. The solid electrolyte member according to the first embodiment contains one type of element M, but may contain a plurality of types of element M. Thus, the solid electrolyte member according to the first embodiment is a solid electrolyte containing lithium, element M, phosphorus, and sulfur, but is not limited thereto, and may be a sulfide-based solid electrolyte containing components other than lithium, element M, and phosphorus. Further, the solid electrolyte member is not limited to having an LGPS-type crystal structure, and Li a M b P c S d is not limited thereto either. Other examples of the composition of the solid electrolyte member will be described later.

[0017] In the solid electrolyte member according to the first embodiment, the content of Li is 8.1% by mass or more and 17.9% by mass or less, more preferably 10.0% by mass or more and 15.0% by mass or less, and even more preferably 10.7% by mass or more and 12.8% by mass or less based on the total content of the elements contained in the solid electrolyte member on a mass basis. By setting the total content of Li within this range, appropriate conductivity can be imparted. The content of Li can be measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES).

[0018] When measuring the content of Li using inductively coupled plasma atomic emission spectroscopy, the following conditions may be applied. · Measuring device: SPS3100 (manufactured by SII NanoTechnology Inc.) · Wavelength range: 160 nm to 770 nm · RF output: 1.4 kW

[0019] In the solid electrolyte member according to the first embodiment, the total content of Al, Zr, Ti, Si, and W is 100 ppm or less, preferably 80 ppm or less, and more preferably 50 ppm or less, based on the total content of the elements contained in the solid electrolyte member on a mass basis. That is, in the solid electrolyte member, the total value of the content of the Al element, the content of the Zr element, the content of the Ti element, the content of the Si element, and the content of the W element preferably falls within the above numerical range with respect to the total value of the contents of all the elements contained in the solid electrolyte member. By the total content of Al, Zr, Ti, Si, and W being within this range, the solid electrolyte member has less impurities and is of high purity, suppressing the amount of by-products generated by the reaction of the impurities and appropriately suppressing the deterioration of battery performance. Note that the contents of Al, Zr, Ti, Si, and W can be measured by X-ray fluorescence spectroscopy (XRF). Here, the battery performance is, for example, the cycle life.

[0020] More specifically, when using X-ray fluorescence spectroscopy, the content of the target element may be calculated based on the peak intensity in the intensity spectrum of the X-ray fluorescence measured by X-ray fluorescence spectroscopy. Specifically, based on the peak intensity of the target element in the intensity spectrum of the X-ray fluorescence, the content of the target element with respect to the total content of the elements (excluding Li) contained in the solid electrolyte member is calculated. Then, using the following formula (1), the content of the target element with respect to the total content of the elements (total content of all elements including Li) contained in the solid electrolyte member is calculated.

[0021] A = A0·(100 - A Li ) ···(1)

[0022] Here, A is the content (mass%) of the target element with respect to the total content of the elements contained in the solid electrolyte member. Also, A0 is the content (mass%) of the target element with respect to the total content of the elements (excluding Li) contained in the solid electrolyte member, calculated based on the peak intensity in the intensity spectrum of the X-ray fluorescence. Also, ALi is the Li content (mass %) calculated using inductively coupled plasma optical emission spectrometry. The total content of Al, Zr, Ti, Si, and W with respect to the total content of elements contained in the solid electrolyte member is calculated by calculating A for each of Al, Zr, Ti, Si, and W and summing up the respective As.

[0023] When using X-ray fluorescence spectrometry, the following conditions may be applied. · Measuring device: M4 TORNADO (manufactured by Bruker) · Excitation X-ray: Polycapillary X-ray optical system Rh tube · Output: 50 kV, 200 μA · X-ray diameter: 20 μm

[0024] In addition, when the solid electrolyte member according to the first embodiment is classified into those with a particle diameter of less than 5 μm, those with a particle diameter of 5 μm or more and less than 100 μm, and those with a particle diameter of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, Si, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the solid electrolyte member. That is, among the solid electrolyte members according to the present embodiment, if those with a particle diameter of less than 5 μm are taken as the first solid electrolyte member, in the first solid electrolyte member, the total content of Al, Zr, Ti, Si, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the first solid electrolyte member. Similarly, among the solid electrolyte members according to the present embodiment, if those with a particle diameter of 5 μm or more and less than 100 μm are taken as the second solid electrolyte member, in the second solid electrolyte member, the total content of Al, Zr, Ti, Si, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the second solid electrolyte member. Further, among the solid electrolyte members according to the present embodiment, if those with a particle diameter of 100 μm or more are taken as the third solid electrolyte member, in the third solid electrolyte member, the total content of Al, Zr, Ti, Si, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the third solid electrolyte member. By the total content of Al, Zr, Ti, Si, and W being within this range in each of the classified solid electrolyte members, the solid electrolyte member has less impurities and is of high purity, suppressing the amount of by-products generated by the reaction of impurities, and appropriately suppressing the deterioration of battery performance.

[0025] Note that classification into particles with a particle size of less than 5 μm, particles with a particle size of 5 μm or more and less than 100 μm, and particles with a particle size of 100 μm or more may be performed using a sieve of SUS or nylon mesh. For example, particles with a particle size of less than 5 μm may be classified using a nylon mesh (Tantore #508 / 585 - 5 mesh opening 5 μm). Further, particles with a particle size of 5 μm or more and less than 100 μm may be classified using a SUS sieve with a nominal mesh opening of 100 μm corresponding to JIS standard (JIS Z8801-1). And the particles with a particle size of less than 5 μm and the particles remaining without being classified as particles with a particle size of 5 μm or more and less than 100 μm may be treated as particles with a particle size of 100 μm or more. Also, the particle size may be measured using a particle size distribution measuring device, for example, a laser diffraction scattering type particle size distribution measuring device LA-960 (manufactured by Horiba, Ltd.).

[0026] Further, the solid electrolyte member according to the first embodiment preferably has an average crystallite size of 50 nm or more, more preferably 60 nm or more and 500 nm or less, and still more preferably 70 nm or more and 500 nm or less. When the average crystallite size of the solid electrolyte member is within this range, the material has undergone crystal growth, and the battery performance can be improved. Furthermore, when the crystal growth has progressed in this way, by-products are likely to be generated due to the reaction of impurities. However, since the amount of impurities is small as described above, it is possible to suppress the deterioration of the battery performance while improving the battery performance. The average crystallite size can be measured by the X-ray diffraction method. More specifically, it can be measured by powder X-ray diffraction measurement using CuKα as the radiation source and setting the measurement range of the diffraction angle 2θ to 10° or more and 60° or less. As a result of the powder X-ray diffraction measurement, an X-ray diffraction spectrum is obtained, where the horizontal axis is 2θ and the vertical axis is the relative intensity when the maximum peak intensity among all the peaks within the measurement range is set to 1. Then, in the X-ray diffraction spectrum, the average crystallite size can be measured by substituting the diffraction angle of the peak and the obtained half-value width into the following formula (2), which is Scherrer's formula. However, D is the crystallite size (average crystallite size), K is the Scherrer constant, and B is the half-value width of the peak.

[0027] D = Kλ / Bcosθ ···(2)

[0028] In addition, the solid electrolyte member according to the first embodiment preferably has a conductivity of 1 mS / cm or more, more preferably 3 mS / cm or more, and still more preferably 4 mS / cm or more. By setting the conductivity within this numerical range, the battery performance as a solid electrolyte member can be appropriately maintained.

[0029] (Method for manufacturing a solid electrolyte member) Next, a method for manufacturing the solid electrolyte member according to the present embodiment will be described. However, the following manufacturing method is an example, and the solid electrolyte member according to the present embodiment may be manufactured by any method without being limited to the following description.

[0030] FIG. 1 is a flowchart showing a method for manufacturing a solid electrolyte member according to the present embodiment. As shown in FIG. 1, in the manufacturing method of the present embodiment, first, in the preparation step, an aggregate of starting material A for the solid electrolyte member is prepared (step S10; preparation step). The starting material A is each raw material containing the elements constituting the solid electrolyte member. Here, the aggregate of the starting material A refers to a mixture (stirring) of the powders of the respective raw materials (each starting material A) without chemical changes in the respective raw materials. Here, it is preferable that the respective raw materials are mixed so as to be homogeneous. In this way, the starting material A refers to one type of raw material, and the aggregate of the starting material A refers to an aggregate in which the respective starting materials A are mixed. Further, the aggregate of the starting material A is not an intermediate product generated during the process of generating the solid electrolyte member, but an aggregate of raw materials in a state before starting the process of generating the solid electrolyte member. More specifically, the aggregate of the starting material A here refers to the raw materials in a state before being housed in the furnace 10 described later. In this manufacturing method, elemental sulfur and a raw material containing any one of Li, P, and M are used as starting materials.

[0031] (Elemental sulfur) Elemental sulfur refers to sulfur that does not contain elements other than sulfur, excluding inevitable impurities. Hereinafter, unless otherwise specified, each raw material may contain inevitable impurities.

[0032] (Raw materials of S, Li, P, and M) Since the starting material A contains the elements constituting the solid electrolyte member, in this embodiment, it can be said that the starting material A includes an S raw material containing sulfur, an Li raw material containing lithium, a P raw material containing phosphorus, and an M raw material containing element M.

[0033] (S raw material) As described above, the S raw material is elemental sulfur.

[0034] (Li raw material) The Li raw material is at least one of elemental lithium, a compound of lithium and element M, a compound of lithium and phosphorus, a compound of lithium, element M, and phosphorus, a compound of lithium and sulfur (lithium sulfide), a compound of lithium, element M, and sulfur (such as Li4GeS4, Li4SnS4, etc.), a compound of lithium, phosphorus, and sulfur (such as Li3PS4), and a compound of lithium, element M, phosphorus, and sulfur. When the Li raw material is a compound of lithium and other elements, the Li raw material also serves as the raw material of the other elements. For example, when the Li raw material is a compound of lithium and phosphorus, the compound of lithium and phosphorus can be said to be both the Li raw material and the P raw material.

[0035] (P raw material) The P raw material is at least one of elemental phosphorus, a compound of lithium and phosphorus, a compound of element M and phosphorus, a compound of lithium, element M, and phosphorus, a compound of phosphorus and sulfur (phosphorus sulfide), a compound of lithium, phosphorus, and sulfur (such as Li3PS4), a compound of element M, phosphorus, and sulfur, and a compound of lithium, element M, phosphorus, and sulfur.

[0036] (M raw material) The M raw material is at least one of elemental element M, a compound of lithium and element M, a compound of element M and phosphorus, a compound of lithium, element M, and phosphorus, a compound of element M and sulfur (such as GeS, GeS2, SnS, SnS2, etc.), a compound of lithium, element M, and sulfur, a compound of element M, phosphorus, and sulfur (such as GeP, Sn3P4, etc.), and a compound of lithium, element M, phosphorus, and sulfur.

[0037] (Hybrid method) Next, the mixing method of each raw material will be described. In the preparation step, each raw material (elemental sulfur, Li raw material, P raw material, M raw material) is weighed at a weight ratio such that it becomes the composition of the solid electrolyte member to be produced, and as starting material A, each starting material A is mixed to form an aggregate of starting material A. In the present embodiment, elemental sulfur, the Li raw material, the P raw material, and the M raw material are weighed and mixed in a glove box under an argon atmosphere, but it is not limited thereto, and for example, they may be mixed in an inert gas atmosphere such as nitrogen. Further, in the present embodiment, the mixed elemental sulfur, the Li raw material, the P raw material, and the M raw material are compacted and formed into pellets, but it is not limited to being formed into pellets.

[0038] In the preparation step, each raw material (elemental sulfur, Li raw material, P raw material, M raw material) weighed as starting material A is mixed to form an aggregate of starting material A. The mixing here refers to stirring to such an extent that each raw material is uniformly dispersed, and does not involve mechanical or chemical changes of each raw material such as the mechanical milling method. Therefore, when the aggregate of starting material A produced by this manufacturing method is measured by X-ray diffraction using CuKα rays, the crystal peaks of the crystalline substances constituting starting material A are detected, and no other crystal peaks are detected. Also, when using, for example, Li2S, elemental P, and metallic Sn (elemental Sn) as elemental sulfur, the Li raw material, the P raw material, and the M raw material, when the aggregate of starting material A produced by this manufacturing method is measured by X-ray diffraction using CuKα rays, the peaks from formula (3) to formula (11) below are detected as crystal peaks. Here, the crystal peak refers to a peak whose intensity is equal to or higher than a threshold value, and the threshold value here is, for example, a relative intensity of 0.05 when the maximum peak intensity of the measurement result is set to 1.

[0039] 2θ = 23.06 ± 0.50 ··· (3) 2θ = 25.83 ± 0.50 ··· (4) 2θ = 27.00 ± 0.50 ··· (5) 2θ = 27.71 ± 0.50 ··· (6) 2θ = 30.63 ± 0.50 ··· (7) 2θ = 32.01 ± 0.50 ··· (9) 2θ = 44.81 ± 0.50 ··· (10) 2θ = 44.89 ± 0.50 ··· (11)

[0040] In the preparation step, the mixing conditions of each raw material are set such that the mixing time is 10 minutes or less, and the upper limit of the load per unit area applied in the shearing direction is 0.1 N / mm 2 or less, enabling appropriate detection of the crystal peaks of each raw material in the generated starting material A.

[0041] As shown in FIG. 1, when the aggregate of starting material A is prepared in the preparation step, the aggregate of starting material A is heated to perform a generation step of generating a solid electrolyte member (step S12; generation step). That is, before the generation step, the elemental sulfur, Li raw material, P raw material, and M raw material contained in the starting material A are not bonded to each other by a chemical reaction, but in the generation step, they are bonded by a chemical reaction, and the chemical formula is Li a M b P c S d and a solid electrolyte member represented by is generated. Specifically, in the generation step, the starting material A is heated to temperature T1 and held at temperature T1 for a predetermined holding time to generate a solid electrolyte member. Temperature T1 is preferably 400°C or higher and 1000°C or lower, more preferably 500°C or higher and 600°C or lower, and even more preferably 500°C or higher and 560°C or lower. By setting temperature T1 within this numerical range, the liquefied elemental sulfur can be bonded to the raw materials other than S by a chemical reaction, and a solid electrolyte member can be appropriately generated. Also, the holding time at temperature T1 is preferably 1 hour or longer and 72 hours or shorter, more preferably 1 hour or longer and 24 hours or shorter, and even more preferably 1 hour or longer and 12 hours or shorter. By setting the holding time within this numerical range, each raw material can be appropriately reacted to appropriately generate a solid electrolyte member.

[0042] Figure 2 is a schematic diagram of the equipment for producing the solid electrolyte member. As shown in Figure 2, the furnace 10 is a furnace for heating the starting material A to produce the solid electrolyte member. The furnace 10 is provided with a heating unit 12. The heating unit 12 is a heat source for heating the inside of the furnace 10. Note that the structure of Figure 2 is an example, and the equipment for producing the solid electrolyte member is not limited to the structure of Figure 2.

[0043] In the production step, in a predetermined gas atmosphere, the starting material A is stored in the furnace 10 and the furnace 10 is sealed. Then, the inside of the furnace 10 in which the starting material A is stored is heated by the heating unit 12 to reach the temperature T1, and the temperature is maintained at T1 for a predetermined holding time. The gas filled in the furnace 10 may be any gas, and may be an inert gas (noble gas) such as argon, or may be hydrogen sulfide. Note that it is not essential to seal the furnace. For example, the furnace may be heated while supplying a predetermined gas without sealing. For example, it may be heated while supplying argon at 100 mL / min. The elemental sulfur in the starting material A melts and liquefies before reaching the temperature T1, and a solid electrolyte member is produced by the solid-liquid reaction between the liquefied sulfur and other raw materials.

[0044] In this way, in this manufacturing method, after the starting material A is stored in the furnace 10, the solid electrolyte member is produced without taking out the starting material A from the furnace 10. In other words, in this manufacturing method, the sulfides (intermediate products) of Li, P, and element M produced from the starting material A are kept in the furnace 10, that is, without being taken out from the furnace 10, the solid electrolyte member is produced. That is, the sulfides (intermediate products) of Li, P, and element M produced from the starting material A react while being sealed in the furnace 10 in a predetermined gas atmosphere without being exposed to the atmosphere, and become a solid electrolyte member.

[0045] In addition, in this embodiment, only one-step heating at temperature T1 is performed in the generation step, but heating in multiple steps may be performed. In this case, for example, before heating at temperature T1, a step of heating at temperature T2 for a predetermined time to melt elemental sulfur may be executed. By providing the step of heating at temperature T2, it becomes possible to perform firing at temperature T1 in a state where elemental sulfur is surely liquefied, and a solid electrolyte member can be appropriately generated. The temperature T2 here is lower than temperature T1 and higher than the melting point of elemental sulfur, for example, 115°C or higher and 150°C or lower.

[0046] (Effect) Here, when the solid electrolyte member contains impurities such as Al, Zr, Ti, Si, and W in addition to the composition of Li, P, and S, etc., these impurities may react to generate by-products. When by-products are formed, the battery characteristics of the solid electrolyte member may deteriorate. Here, the battery performance is, as described above, for example, the cycle life. On the other hand, the solid electrolyte member according to the present embodiment contains Li, P, and S, and the content of Li measured by ICP emission spectrometry is 8.1% by mass or more and 17.9% by mass or less based on the total content of the elements contained in the solid electrolyte member. Further, in the solid electrolyte member according to the present embodiment, the total content of Al, Zr, Ti, Si, and W measured by fluorescent X-ray analysis is less than 100 ppm based on the total content of the elements contained in the solid electrolyte member. Further, when the solid electrolyte member according to the present embodiment is classified into particles with a particle diameter of less than 5 μm, particles with a particle diameter of 5 μm or more and less than 100 μm, and particles with a particle diameter of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, Si, and W measured by fluorescent X-ray analysis is less than 100 ppm based on the total content of the elements contained in the solid electrolyte member. Therefore, the solid electrolyte member according to the present embodiment can preferably suppress the deterioration of battery performance by reducing the content of impurities regardless of the whole and the particle size. Furthermore, impurities present near the surface are more likely to react, but the solid electrolyte member according to the present embodiment also has a small amount of impurities even for a solid electrolyte member with a small particle diameter that tends to have a higher ratio of impurities present near the surface, so the deterioration of battery performance can be preferably suppressed.

[0047] In addition, the solid electrolyte member according to the present embodiment preferably has an average crystallite diameter of 50 nm or more and a conductivity of 4 mS / cm or more. By having an average crystallite diameter of 50 nm or more, the solid electrolyte member according to the present embodiment can appropriately improve battery performance. Furthermore, in a state where crystal growth has progressed in this way, by-products are likely to be generated due to the reaction of impurities. However, since the amount of impurities in the solid electrolyte member according to the present embodiment is small as described above, it is possible to suppress deterioration of battery performance while improving battery performance.

[0048] In addition, the solid electrolyte member according to the present embodiment preferably has an LGPS-type crystal structure. By being of the LGPS type, it can be suitably used for lithium batteries and the like.

[0049] In addition, the solid electrolyte member according to the present embodiment preferably has a crystal structure of space group P42nmc, and when measured by X-ray diffraction using CuKα radiation, the peaks of the following formulas (12) to (16) are preferably detected. Further, when the solid electrolyte member according to the present embodiment is measured by X-ray diffraction using CuKα radiation, whether the peak of formula (17) is detected as a crystal peak on the higher angle side than the peak of formula (15), or the diffraction intensity of the peak of formula (16) is I A is denoted as I B and the diffraction intensity of the peak of formula (17) is I B / I A is preferably less than 0.50, i.e., the solid electrolyte member according to the present embodiment is of the so-called LGPS type, Li a M b P c S d (more preferably Li 10 GeP2S 12 ). Note that the diffraction intensity refers to the peak height of the waveform measured by X-ray diffraction.

[0050] 2θ = 17.38° ± 0.50° ··· (12) 2θ = 20.18° ± 0.50° ··· (13) 2θ = 20.44° ± 0.50° ··· (14) 2θ = 26.96° ± 0.50° ··· (15) 2θ = 29.58° ± 0.50° ··· (16) 2θ = 27.33° ± 0.50° ··· (17)

[0051] Moreover, the method for manufacturing the solid electrolyte member according to the present embodiment preferably includes a preparation step of preparing an aggregate of starting materials containing Li, P, and S, and a generation step of heating the aggregate of starting materials to generate the solid electrolyte member. In the preparation step, when the generated aggregate of starting materials is measured by X-ray diffraction, it is preferable to mix the starting materials to generate an aggregate of starting materials so that crystal peaks of crystalline substances can be detected. According to this manufacturing method, since the solid electrolyte member is manufactured by a solid-liquid reaction, the solid electrolyte member can be appropriately manufactured by mixing to such an extent that crystals remain. Therefore, according to this manufacturing method, the mixing process can be simplified, enabling the production of many solid electrolyte members in a short time. At the same time, mechanical milling is not required, suppressing the incorporation of impurities during the manufacturing process and suppressing the deterioration of battery performance.

[0052] (Second Embodiment) Next, the second embodiment will be described. The solid electrolyte member according to the first embodiment mainly contains Li, P, and S and substantially does not contain Si, whereas the solid electrolyte member according to the second embodiment is different from the first embodiment in that it also contains Si. The parts having the same configuration as those in the first embodiment in the second embodiment will not be described.

[0053] The solid electrolyte member according to the second embodiment contains Li, Si, P, and S. In other words, as element M, it contains at least Si. In the second embodiment, as element M, it may contain only Si, or in addition to Si, it may contain at least one element of Group 13, Group 14, and Group 15 excluding Al and Si. Further, in the second embodiment, as element M, in addition to Si, it may contain at least one of Ge and Sn.

[0054] Regarding the solid electrolyte member according to the second embodiment, the total content of Al, Zr, Ti, and W is 100 ppm or less, preferably 80 ppm or less, and more preferably 50 ppm or less, based on the total content of the elements contained in the solid electrolyte member by mass. That is, for the solid electrolyte member, it is preferable that the total value of the content of the Al element, the content of the Zr element, the content of the Ti element, and the content of the W element falls within the above numerical range with respect to the total value of the contents of all the elements contained in the solid electrolyte member. When the total content of Al, Zr, Ti, and W in the solid electrolyte member is within this range, the solid electrolyte member has less impurities and is of high purity, suppressing the amount of by-products generated by the reaction of the impurities and appropriately suppressing the deterioration of battery performance. Note that the contents of Al, Zr, Ti, and W can be measured by X-ray fluorescence analysis.

[0055] In addition, when the solid electrolyte member according to the second embodiment is classified into those with a particle diameter of less than 5 μm, those with a particle diameter of 5 μm or more and less than 100 μm, and those with a particle diameter of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the solid electrolyte member. That is, among the solid electrolyte members according to the present embodiment, when the one with a particle diameter of less than 5 μm is defined as the first solid electrolyte member, in the first solid electrolyte member, the total content of Al, Zr, Ti, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the first solid electrolyte member. Similarly, among the solid electrolyte members according to the present embodiment, when the one with a particle diameter of 5 μm or more and less than 100 μm is defined as the second solid electrolyte member, in the second solid electrolyte member, the total content of Al, Zr, Ti, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the second solid electrolyte member. Further, among the solid electrolyte members according to the present embodiment, when the one with a particle diameter of 100 μm or more is defined as the third solid electrolyte member, in the third solid electrolyte member, the total content of Al, Zr, Ti, and W measured by the fluorescent X-ray analysis method is less than 100 ppm, preferably 80 ppm or less, and more preferably 50 ppm or less on a mass basis with respect to the total content of the elements contained in the third solid electrolyte member.

[0056] As described above, the solid electrolyte member according to the second embodiment contains Li, Si, P, and S, and the content of Li measured by ICP emission spectrometry is 8.1% by mass or more and 17.9% by mass or less based on the total content of the elements contained in the solid electrolyte member. Further, in the solid electrolyte member according to the second embodiment, the total content of Al, Zr, Ti, and W measured by fluorescent X-ray analysis is less than 100 ppm based on the total content of the elements contained in the solid electrolyte member. Further, when the solid electrolyte member according to the second embodiment is classified into particles having a particle diameter of less than 5 μm, a particle diameter of 5 μm or more and less than 100 μm, and a particle diameter of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, and W measured by fluorescent X-ray analysis is less than 100 ppm based on the total content of the elements contained in the solid electrolyte member. Therefore, the solid electrolyte member according to the second embodiment can preferably suppress the deterioration of battery performance by reducing the content of impurities regardless of the whole and the particle size.

[0057] Note that the manufacturing method of the solid electrolyte member of the second embodiment is the same as that of the first embodiment except that a raw material containing Si is used as the M raw material, and thus the description thereof is omitted.

[0058] (Other examples) In the above description, the solid electrolyte member has a chemical formula of Li a M b P c S d However, the composition is not limited thereto. Hereinafter, modified examples of the solid electrolyte member will be described. Note that the modified examples described hereinafter are applicable to both the solid electrolyte member of the first embodiment and the solid electrolyte member of the second embodiment.

[0059] (First modified example) As described in the first modified example, the solid electrolyte member has a chemical formula of Li a M b P c S d Ha eIt may be represented by the following. Here, a, b, c, d, and e are numbers greater than 0. Also, the element Ha is a halogen element, and more preferably, it is at least one element selected from F, Cl, Br, and I.

[0060] In the case where the solid electrolyte member of the first modification is measured by the X-ray diffraction method using CuKα rays, it is preferable that peaks are detected at the positions from the following formula (18) to formula (19).

[0061] 2θ = 26.96° ± 0.50° ··· (18) 2θ = 29.58° ± 0.50° ··· (19)

[0062] Also, in the case where the solid electrolyte member of the first modification is measured by the X-ray diffraction method using CuKα rays, a peak may or may not be detected at the position of the following formula (20) on the higher angle side than the peak of formula (18). That is, in the first modification, a solid electrolyte member in which a peak is detected at the position of formula (20) may be manufactured, or a solid electrolyte member in which a peak is not detected at the position of formula (20) may be manufactured.

[0063] 2θ = 27.33° ± 0.50° ··· (20)

[0064] Here, the diffraction intensity of the peak at the position of formula (19) in the X-ray diffraction measurement of the solid electrolyte member of the first modification using CuKα rays is I A And the opening intensity at the position of formula (20) in the X-ray diffraction measurement using CuKα rays is I B When B / I A The value of is preferably less than 0.50.

[0065] (Second modification) As described in the second modification, the solid electrolyte member has a chemical formula of Li a M b P c X d S e Ha fIt is represented by. Here, a, b, c, d, e, f are numbers greater than 0. Element Ha is a halogen element, more preferably at least one element of F, Cl, Br, and I. Element X is an element of Group 16 other than S, more preferably at least one element of O, Se, and Te.

[0066] The solid electrolyte member of the second modification is preferably such that a peak is detected at the position of formula (14), similar to the solid electrolyte member of the first modification. Also, the solid electrolyte member manufactured in the second modification may or may not have a peak detected at the position of formula (19), similar to the solid electrolyte member of the first modification. The solid electrolyte member of the second modification is similar to the solid electrolyte member of the second embodiment, I B / I A It is preferable that the value of is less than 0.50.

[0067] In the second modification, although element Ha and element X are introduced into the solid electrolyte member of this embodiment, element X may be introduced without introducing element Ha. That is, the solid electrolyte member is Li a M b P c X d S e It may be represented by. In this case, a, b, c, d, e are numbers greater than 0.

[0068] (Third modification) The solid electrolyte member of the third modification has a crystal phase of an Argyrodite-type crystal structure. The solid electrolyte member of the third modification has a chemical formula of Li a P b S c Ha d It is represented by. Here, a, b, c, d are numbers greater than 0. Element Ha is a halogen element, more preferably at least one element of F, Cl, Br, and I.

[0069] (Fourth modification) The solid electrolyte member of the fourth modification has a crystal phase with an Argyrodite-type crystal structure. The solid electrolyte member of the fourth modification has a chemical formula of Li a P b X c S d Ha e where a, b, c, d, and e are numbers greater than 0. The element Ha is a halogen element, and more preferably, at least one element of F, Cl, Br, and I. The element X is a Group 16 element other than S, and more preferably, at least one element of O, Se, and Te.

[0070] (Fifth Modification) The solid electrolyte member of the fifth modification has a chemical formula of Li a M b S c where a, b, and c are numbers greater than 0.

[0071] In the fifth modification, it was the solid electrolyte member of the present embodiment excluding P, but an element X may be introduced thereto. That is, the solid electrolyte member may be Li a M b X c S d In this case, a, b, c, and d are numbers greater than 0, and the element X is a Group 16 element other than S, and more preferably, at least one element of O, Se, and Te.

[0072] (Examples) Next, examples will be described. Table 1 shows the blending amounts of the raw materials for each example.

[0073] [Table 1]

[0074] (Example 1) In Example 1, elemental sulfur was used as the starting material, lithium sulfide was used as the Li raw material, elemental phosphorus was used as the P raw material, and metallic tin was used as the M raw material. In a glove box with an argon atmosphere and a dew point of -70°C or lower, elemental sulfur, lithium sulfide, elemental phosphorus, and metallic tin were weighed so as to have a desired composition, and mixed in a SUS mortar for 5 minutes until the color became uniform, and then formed into pellets. Here, 0.71 g of elemental sulfur, 0.72 g of lithium sulfide, 0.20 g of elemental phosphorus, and 0.37 g of metallic tin were mixed. Then, the pellets placed in a carbon firing container were installed in the furnace, and the inside of the furnace was heated and held at 560°C in an argon atmosphere. The holding time here was 6 hours. Then, it was cooled at 1°C / min to obtain a solid electrolyte member.

[0075] (Example 2) In Example 2, elemental sulfur was used as the starting material, lithium sulfide was used as the Li raw material, elemental phosphorus was used as the P raw material, and metallic silicon was used as the M raw material. In a glove box with an argon atmosphere and a dew point of -70°C or lower, elemental sulfur, lithium sulfide, elemental phosphorus, and metallic silicon were weighed so as to have a desired composition, and mixed in a SUS mortar for 5 minutes until the color became uniform, and then formed into pellets. Here, 0.83 g of elemental sulfur, 0.84 g of lithium sulfide, 0.23 g of elemental phosphorus, and 0.10 g of metallic silicon were mixed. Then, the pellets placed in a carbon firing container were installed in the furnace, and the inside of the furnace was heated and held at 560°C in an argon atmosphere. The holding time here was 6 hours. Then, it was cooled at 1°C / min to obtain a solid electrolyte member.

[0076] (Example 3) In Example 3, elemental sulfur was used as the starting material, lithium sulfide and lithium chloride were used as the Li raw materials, and elemental phosphorus was used as the P raw material. In a glove box with an argon atmosphere and a dew point of -70°C or lower, elemental sulfur, lithium sulfide, lithium chloride, and elemental phosphorus were weighed so as to have a desired composition, and mixed in a SUS mortar for 5 minutes until the color became uniform, and then formed into pellets. Here, 0.60 g of elemental sulfur, 0.92 g of lithium sulfide, 0.28 g of lithium chloride, and 0.23 g of elemental phosphorus were mixed. Then, the pellets placed in a carbon firing container were installed in the furnace, and the inside of the furnace was heated and held at 500°C in an argon atmosphere. The holding time here was 6 hours. Thereafter, it was cooled at 1°C / min to obtain a solid electrolyte member.

[0077] (Comparative Example 1) In Comparative Example 1, lithium sulfide was used as the Li raw material, phosphorus sulfide was used as the P raw material, and tin sulfide was used as the M raw material. Here, 0.72 g of lithium sulfide, 0.70 g of phosphorus sulfide, and 0.58 g of tin sulfide were mixed. Also, for the mixing conditions, a ball mill using 10 mmφ tungsten carbide media was used, and after mixing at 360 rpm for 24 hours, it was formed into pellets. Then, the pellets placed in an alumina firing container were installed in the furnace, and the inside of the furnace was heated and held at 560°C in an argon atmosphere. The holding time here was 6 hours. Thereafter, it was cooled at 1°C / min to obtain a solid electrolyte member.

[0078] (Measurement of Li Content) For each example, the Li content was measured using inductively coupled plasma optical emission spectrometry. As a pretreatment, the solution obtained by sealed pressure decomposition using aqua regia hydrofluoric acid was subjected to white smoke treatment using sulfuric acid, and the solution to which hydrochloric acid and water were added was used as the measurement solution. The apparatus used was an inductively coupled plasma optical emission analyzer SPS3100 manufactured by SII Nanotechnology.

[0079] (Measurement of Contents of Elements Other than Li) For each example, the contents of elements other than Li were measured using X-ray fluorescence spectrometry. The measurement conditions were as follows. · Measuring device: M4 TORNADO (manufactured by Bruker) · Excitation X-ray: Polycapillary X-ray optical system Rh tube · Output: 50 kV, 200 μA · X-ray diameter: 20 μm

[0080] Also, for each example, the first solid electrolyte member with a particle size of less than 5 μm, the second solid electrolyte member with a particle size of 5 μm or more and less than 100 μm, and the third solid electrolyte member with a particle size of 100 μm or more were classified, and for each of the first solid electrolyte member, the second solid electrolyte member, and the third solid electrolyte member, the content of elements other than Li was measured under the above conditions using the fluorescent X-ray analysis method.

[0081] (Measurement results of the content of each element) Table 2 shows the measurement results of the content of each element.

[0082]

Table 2

[0083] In Table 2, the ICP result is the content (mass %) of Li with respect to the total content of elements contained in the solid electrolyte member measured using inductively coupled plasma optical emission spectrometry. Also, the XRF result is the content (mass %) of the target element with respect to the total content of elements excluding Li among all the elements contained in the solid electrolyte member measured using the fluorescent X-ray analysis method. Also, the mass ratio is the content (mass %) of Li with respect to the total content of elements contained in the solid electrolyte member measured using inductively coupled plasma optical emission spectrometry for Li, and for elements other than Li, it is a value calculated using the formula (1) of the above-described embodiment.

[0084] As shown in Table 2, in Example 1, in the unclassified solid electrolyte member (the entire solid electrolyte member), the content of Al was 40 ppm and the content of Si was 19 ppm, and since Zr, Ti, and W were not detected, the total content of Al, Zr, Ti, Si, and W was less than 100 ppm. Similarly, in Example 2, in the unclassified solid electrolyte member (the entire solid electrolyte member), the Al content was 44 ppm, and Zr, Ti, and W were not detected. Therefore, the total content of Al, Zr, Ti, and W was less than 100 ppm. Similarly, in Example 3, in the unclassified solid electrolyte member (the entire solid electrolyte member), the Al content was 52 ppm, the Si content was 25 ppm, and Zr, Ti, and W were not detected. Therefore, the total content of Al, Zr, Ti, Si, and W was less than 100 ppm. On the other hand, in Comparative Example 1, in the unclassified solid electrolyte member (the entire solid electrolyte member), the Al content was 978 ppm, the Si content was 459 ppm, the W content was 214 ppm, and Zr and Ti were not detected. Therefore, the total content of Al, Zr, Ti, Si, and W was outside the range of less than 100 ppm.

[0085] Also, as shown in Table 2, in Example 1, for each of the classified first solid electrolyte member, second solid electrolyte member, and third solid electrolyte member, the total content of Al, Zr, Ti, and W was less than 100 ppm. In Comparative Example 1, for each of the classified first solid electrolyte member, second solid electrolyte member, and third solid electrolyte member, the total content of Al, Zr, Ti, and W was outside the range of less than 100 ppm.

[0086] (Average crystallite size) Also, for the solid electrolyte member of each example, the average crystallite size (nm) was measured using the method described in this embodiment. The measurement results are shown in Table 2.

[0087] (Conductivity) Also, for the solid electrolyte member of each example, it was pulverized in an agate mortar in a glove box under an argon atmosphere, and AC impedance measurement was performed using a Biologic potentiostat / galvanostat SP-300 with a conductivity measurement cell made of SUS to measure the conductivity. The measurement conditions were a measurement range of 1 Hz to 1 MHz at 25°C. The measurement results of each conductivity are shown in Table 2.

[0088] (Crystal structure) Also, for the solid electrolyte member of each example, an X-ray diffraction spectrum was measured using CuKα rays to confirm the crystal structure. FIG. 3 is a graph showing the XRD spectra of each example. Table 3 shows the diffraction angles and relative intensities of the crystal peaks confirmed at 2θ = 15° to 55°, and the space group of the estimated crystal structure. The crystal peak is defined as a peak having an intensity equal to or higher than a threshold value, and the threshold value here is, for example, a relative intensity of 0.05 when the maximum peak intensity of the measurement result is set to 1. Table 3 shows that Example 1 and Example 2 have the LGPS structure. The LGPS structure in Table 3 has a crystal structure of space group P42nmc, and when measured by X-ray diffraction measurement using CuKα rays, the peaks of the following formulas (A) to (E) are detected as crystal peaks, and the diffraction intensity of the peak of formula (E) is I A and the diffraction intensity of the peak of formula (F) is I B When, B / I A is less than 0.50, it means a structure. 2θ = 17.38° ± 0.50° ··· (A) 2θ = 20.18° ± 0.50° ··· (B) 2θ = 20.44° ± 0.50° ··· (C) 2θ = 26.96° ± 0.50° ··· (D) 2θ = 29.58° ± 0.50° ··· (E) 2θ = 27.33° ± 0.50° ··· (F) Also, Table 3 shows that Example 3 has an Argyrodite-type crystal structure.

[0089]

Table 3

[0090] (Evaluation) Figure 4 is a graph showing the measurement results of cycle life. A solid electrolyte member obtained as described above was used as a separator, which was formed into a pellet with a diameter of 10 mm at a molding pressure of 600 MPa. As the cathode, lithium cobaltate coated with lithium niobate was used, and as the anode, a lithium-indium alloy was used to prepare a sandwiched all-solid-state lithium battery. In addition, a constant current test was performed on the prepared all-solid-state lithium battery at a current of 1 / 10 C (= 15 mA / g). The results up to 100 cycles when the initial discharge current capacity was set to 100% are shown in Figure 4. As shown in Figure 4, in Examples 1, 2, and 3, it can be seen that compared with Comparative Example 1, the deterioration when passing through charge-discharge cycles can be suppressed, and the deterioration of battery performance can be preferably suppressed. This is presumably because the amount of impurities such as Al, Zr, Ti, Si, and W is small, so the amount of by-products derived from impurities is suppressed, and the deterioration of battery performance is suppressed. Although Si is contained in Example 2, in this case, Si constitutes the solid electrolyte crystal, so it is considered that no by-products were generated and it did not contribute to the deterioration of battery performance.

[0091] As described above, the embodiments of the present invention have been described, but the embodiments are not limited by the contents of these embodiments. In addition, the above-described components include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those within the so-called equivalent range. Furthermore, the above-described components can be combined as appropriate. Moreover, various omissions, substitutions, or changes of the components can be made without departing from the gist of the above-described embodiments.

Explanation of Reference Numerals

[0092] A Starting material

Claims

1. A solid electrolyte member containing Li, P, and S, wherein the content of Li measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) is 8.1% by mass or more and 17.9% by mass or less based on the total content of elements contained in the solid electrolyte member, and the total content of Al, Zr, Ti, Si, and W measured by X-ray fluorescence spectroscopy (XRF) is less than 100 ppm based on the total content of elements contained in the solid electrolyte member. When the solid electrolyte member is classified into particles with a particle diameter of less than 5 μm, particles with a particle diameter of 5 μm or more and less than 100 μm, and particles with a particle diameter of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, Si, and W measured by X-ray fluorescence spectroscopy is less than 100 ppm based on the total content of elements contained in the solid electrolyte member. Solid electrolyte member.

2. A solid electrolyte member containing Li, Si, P, and S, wherein the content of Li measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) is 8.1% by mass or more and 17.9% by mass or less based on the total content of elements contained in the solid electrolyte member, and the total content of Al, Zr, Ti, and W measured by X-ray fluorescence spectroscopy (XRF) is less than 100 ppm based on the total content of elements contained in the solid electrolyte member. When the solid electrolyte member is classified into particles with a particle diameter of less than 5 μm, particles with a particle diameter of 5 μm or more and less than 100 μm, and particles with a particle diameter of 100 μm or more, in each of the classified solid electrolyte members, the total content of Al, Zr, Ti, and W measured by X-ray fluorescence spectroscopy is less than 100 ppm based on the total content of elements contained in the solid electrolyte member. Solid electrolyte member.

3. The solid electrolyte member according to claim 1 or claim 2, having an average crystallite diameter of 50 nm or more and a conductivity of 4 mS / cm or more.

4. Space group P4 ２ It has a crystal structure of nmc and, when measured by X-ray diffraction measurement using CuKα rays, the peaks of the following formulas (A) to (E) are detected as crystal peaks, and whether the peak of formula (F) is detected on the higher angle side than the peak of formula (D), or the diffraction intensity of the peak of formula (E) is I Ａ is denoted as I Ｂ for the diffraction intensity of the peak of formula (F), and when I Ｂ / I Ａ is less than 0.50, the solid electrolyte member according to any one of claims 1 to 3, wherein the peak of formula (F) is detected. 2θ = 17.38° ± 0.50°... (A) 2θ = 20.18° ± 0.50°... (B) 2θ = 20.44° ± 0.50°... (C) 2θ = 26.96° ± 0.50°... (D) 2θ = 29.58° ± 0.50°... (E) 2θ = 27.33° ± 0.50°... (F) Claim 5 The solid electrolyte member according to any one of claims 1 to 3, having an argyrodite-type crystal structure. Claim 6 A method for manufacturing the solid electrolyte member according to any one of claims 1 to 5, comprising a preparation step of preparing an aggregate of starting materials containing Li, P, and elemental sulfur, and a generation step of heating the aggregate of the starting materials to generate the solid electrolyte member, wherein in the preparation step, the starting materials are mixed so that crystal peaks of a crystalline substance can be detected when the generated aggregate of the starting materials is measured by X-ray diffraction. A method for manufacturing a solid electrolyte member.

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