Solid electrolyte, solid electrolyte layer, and solid electrolyte battery

Abstract

The solid electrolyte is represented by formula (1), and has two or more peaks, i.e., a peak a and a peak b, at 900-1250 cm <-1 > in a Raman spectrum measured at an excitation wavelength of 532 nm, the peak a having a peak top in the range of 950-1025 cm <-1 >, and the peak b having a peak top in the range of 1026-1110 cm <-1 >. LiaAbZrcBd (SO4) eClfXg... (1) (In the formula, A is at least one element selected from alkali metals and alkaline earth metals, B is at least one element selected from Na, K, Rb, Cs, Mg, Ca, Sr, Ba, B, Si, Al, Ti and the like, X is at least one element selected from F, Br and I, 0.5 < = a < 6, 0 < = b < 6, 0 < c < 2, 0 < = d < 1, 0lt, e < 3, 0lt, f < = 5, and 0 < = g < 5).

Description

Technical Field

[0001] This invention relates to a solid electrolyte, a solid electrolyte layer, and a solid electrolyte battery.

[0002] This application claims priority based on Japanese Patent Application No. 2023-058580 filed in Japan on March 31, 2023, the contents of which are incorporated herein by reference. Background Technology

[0003] In recent years, the rapid development of electronic technology has enabled the miniaturization, lightweighting, thinning, and multifunctionality of portable electronic devices. Consequently, there is a strong demand for smaller, lighter, thinner, and more reliable batteries, which serve as the power source for these devices. Solid electrolyte batteries, using solid electrolytes as the electrolyte, have thus attracted considerable attention. Known solid electrolytes include oxide-based solid electrolytes, sulfide-based solid electrolytes, complex hydride-based solid electrolytes, and halide-based solid electrolytes.

[0004] For example, Non-Patent Document 1 describes the ionic conductivity of Li3ScCl6 as a halide-based solid electrolyte as 3 mS / cm, and states that the potential window on the reduction side is 0.91 V (V vs. Li / Li). ＋ ).

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2022-122849

[0008] Non-patent literature

[0009] Non-licensed reference 1: Jianwen Liang et al., J. Am. Chem. Soc., 2020, 142, 7012-7022.

[0010] Unauthorized literature 2: RJH Clark, “The impact of Laser-Raman spectroscopy oninorganic chemistry”, The SPEX Speaker Vol. XVIII, No. 1 (March, 1973) Summary of the Invention

[0011] The technical problem that the invention aims to solve

[0012] It is generally believed that halide-based solid electrolytes have higher ionic conductivity than oxide-based, sulfide-based, and complex hydride-based solid electrolytes. While Li3ScCl6, as described in Non-Patent Literature 1, exhibits a high ionic conductivity (3 mS / cm), various limitations exist, including situations where the properties described in Non-Patent Literature 1 cannot be directly demonstrated, or where other materials must be chosen. Therefore, among solid electrolytes with the same structure, a structure capable of relatively improving ionic conductivity is sought.

[0013] Li₂ZrCl₆ and Li₂Zr(SO₄)Cl₄ (see, for example, Patent Document 1) are known halide-based solid electrolytes that utilize Zr, which is present in a high proportion in the Earth's crust, as a central metal and are advantageous in terms of resource availability and cost. However, their ionic conductivity is 4 × 10⁻⁶. -4 The charge / discharge rate characteristics of batteries using this solid electrolyte are insufficient (S / cm).

[0014] The inventors conducted repeated and in-depth research and successfully improved the rate characteristics without changing the composition of the halide-based solid electrolyte, thus completing this invention.

[0015] The present invention was made in view of the above-mentioned problems, and its object is to provide a solid electrolyte that can improve rate characteristics, a solid electrolyte layer using the solid electrolyte, and a solid electrolyte battery.

[0016] Technical solutions for solving technical problems

[0017] To address the above problems, the present invention provides the following technical solution.

[0018] The solid electrolyte involved in Method 1 of the present invention is represented by Formula (1), and the Raman spectrum measured at an excitation wavelength of 532 nm is in the range of 900–1250 cm⁻¹. -1 It has two or more peaks, peak a and peak b, wherein peak a is in the range of 950–1025 cm⁻¹. -1 The range has a peak, with peak b ranging from 1026 to 1110 cm⁻¹. -1 The range has a peak.

[0019] Li a A b Zr c B d (SO4) e Cl f X g …(1)

[0020] (In the formula, A is at least one element selected from alkali metals and alkaline earth metals, B is at least one element selected from Na, K, Rb, Cs, Mg, Ca, Sr, Ba, B, Si, Al, Ti, Cu, Sc, Y, Zr, Nb, Ag, In, Sn, Sb, Hf, Ta, W, Au, Bi, X is at least one or more elements selected from F, Br, I, 0.5≤a<6, 0≤b<6, 0<c<2, 0≤d<1, 0 <e<3、0<f≤5、0≤g<5。)

[0021] The solid electrolyte of embodiment 2 of the present invention is characterized in that, in the solid electrolyte of embodiment 1, a Raman spectrum of 900-1250 cm⁻¹ is used. -1 Using the straight line as the baseline, when the intensities of peaks a and b are set as Ia and Ib respectively, Ia > Ib.

[0022] The solid electrolyte layer involved in Embodiment 3 of the present invention contains any one of the solid electrolytes in Embodiments 1 to 2.

[0023] The solid electrolyte battery according to Embodiment 4 of the present invention comprises a solid electrolyte layer, a positive electrode, and a negative electrode, wherein at least one of the positive electrode and the negative electrode contains a solid electrolyte of any one of Embodiments 1 to 2.

[0024] The solid electrolyte battery according to embodiment 5 of the present invention includes a solid electrolyte layer, a positive electrode, and a negative electrode as in embodiment 3.

[0025] The effects of the invention

[0026] The solid electrolyte of the present invention can provide a solid electrolyte, a solid electrolyte layer, and a solid electrolyte battery with high-rate characteristics. Attached Figure Description

[0027] Figure 1 This is a diagram showing the Raman spectrum of Example 1 of this embodiment.

[0028] Figure 2 This is a diagram showing the Raman spectrum of Example 2 of this embodiment.

[0029] Figure 3 This is a diagram showing the Raman spectrum of Comparative Example 1 of this embodiment.

[0030] Figure 4 This is a cross-sectional schematic diagram of the solid electrolyte battery according to this embodiment. Detailed Implementation

[0031] The following is for reference only. Figure 1The following is a detailed description of this embodiment. The accompanying drawings used in the following description are for ease of understanding of the features of the invention; sometimes, enlarged representations of features are used, and sometimes the dimensional ratios of the constituent elements differ from the actual dimensions. The materials, dimensions, etc., exemplified in the following description are examples only; the invention is not limited to these and can be appropriately modified and implemented without altering its spirit.

[0032] Solid electrolyte

[0033] Solid electrolytes are substances that allow ions to move when an external electric field is applied. If the solid electrolyte has high ionic conductivity, the ion exchange in the solid electrolyte battery becomes smoother, and the internal resistance decreases.

[0034] The solid electrolyte contains a halide-based solid electrolyte represented by formula (1). The solid electrolyte may also contain materials derived from raw material powders, in addition to the compounds represented by formula (1) above. Examples of substances derived from raw material powders include Li₂SO₄.

[0035] Li a A b Zr c B d (SO4) e Cl f X g …(1)

[0036] Solid electrolytes can be in the form of powder (granules) or sintered bodies formed by sintering powder. Additionally, solid electrolytes can also be molded bodies formed from compressed powder, molded bodies formed from mixtures of powder and binder, or coatings formed by removing the solvent through heating after coating with a coating containing powder, binder, and solvent. Furthermore, the main structure of a solid electrolyte can be amorphous or crystalline.

[0037] In equation (1), A is at least one element selected from alkali metals and alkaline earth metals. A is replaced by a portion of Li ions. A is, for example, Li, Na, Ca, or K. When A is Na or Ca or K, the potential window on the reduction side of the solid electrolyte widens. From the viewpoint of adjusting the potential window, b preferably satisfies 0 ≤ b < 6.

[0038] In equation (1), B is an element that needs to be included. B is at least one element selected from Na, K, Rb, Cs, Mg, Ca, Sr, Ba, B, Si, Al, Ti, Cu, Sc, Y, Zr, Nb, Ag, In, Sn, Sb, Hf, Ta, W, Au, and Bi. From the perspective of adjusting the ionic conductivity and potential window by including B in the solid electrolyte, d preferably satisfies 0 ≤ d < 1.

[0039] In equation (1), from the perspective of adjusting the carrier concentration, a preferably satisfies 0.5≤a<6.

[0040] In equation (1), from the perspective of adjusting the potential window of the solid electrolyte, c preferably satisfies 0 < c < 2.

[0041] In equation (1), from the viewpoint of adjusting the potential window of the solid electrolyte, e preferably satisfies 0 < e < 3. When e is 0.1 or more, the potential window on the reduction side of the solid electrolyte is widened by containing (SO4). When the content is too high, there is concern about the decrease in the ionic conductivity of the solid electrolyte caused by the narrowing of the space for carrier ion movement. From the viewpoint of suppressing this situation, c is preferably less than 3 and less than 2.5.

[0042] In formula (1), in addition to SO4, it may have at least one group selected from anions. For example, the anion may be selected from OH, BO2, BO3, BO4, B3O6, B4O7, CO3, NO3, AlO2, SiO3, SiO4, Si2O7, Si3O9, Si4O 11 Si6O 18 PO3, PO4, P2O7, P3O 10 , SO3, SO5, S2O3, S2O4, S2O5, S2O6, S2O7, S2O8, BF4, PF6, BOB, (COO)2, N, AlCl4, CF3SO3, CH3COO, CF3COO, OOC-(CH2)2-COO, OOC-CH2-COO , OOC-CH(OH)-CH(OH)-COO, OOC-CH(OH)-CH2-COO, C6H5SO3, OOC-CH=CH-COO, C(OH)(CH2COOH)2COO, AsO4, BiO4, CrO4, MnO4, PtF6, PtCl6 At least one group selected from PtBr6, PtI6, SbO4, SeO4, TeO4, HCOO, CH3COO, and O (BOB is bis(oxalato)borate, OOC-(CH2)2-COO is succinate, OOC-CH2-COO is malonate, OOC-CH(OH)-CH(OH)-COO is tartrate, OOC-CH(OH)-CH2-COO is malate, C6H5SO3 is benzenesulfonate, OOC-CH=CH-COO is fumarate, OOC-CH=CH-COO is maleate, and C(OH)(CH2COOH)2COO is citrate). This is preferred from the viewpoint of adjusting ionic conductivity and potential window by selecting the above-mentioned groups (excluding SO4) for the anion.

[0043] In equation (1), from the viewpoint of adjusting the potential window of the solid electrolyte, f preferably satisfies 0. <f≤5。

[0044] In formula (1), X is at least one selected from F, Br, and I. X has a large average valence and ionic radius. By including X in the solid electrolyte, the conductivity, oxidation resistance, and reduction resistance of lithium ions within the solid electrolyte are adjusted. From the viewpoint of improving the balance between oxidation resistance and reduction resistance of the solid electrolyte, X preferably contains F. From the viewpoint of improving the reduction resistance of the solid electrolyte, X preferably contains I. It may also contain two or more selected from F, Br, and I. From the viewpoint of adjusting ionic conductivity and potential window, it is preferable to satisfy 0 ≤ g < 5.

[0045] As solid electrolytes, for example, Li2ZrSO4Cl4, Li3YSO4Cl4, Li3ScSO4Cl4, and Li3InSO4Cl4.

[0046] In Raman spectroscopy, light is incident on a substance, and the substance is evaluated based on the Raman scattered light, which has a different wavelength from the incident light. The wavelength difference between the Raman scattered light and the incident light corresponds to a portion of the vibrational energy possessed by the substance. Therefore, various physical properties of the substance can be investigated based on Raman spectra. Thus, in amorphous substances, features that cannot be investigated by X-ray diffraction can be captured. In the case of solids with regular lattices and high crystallinity, the peaks corresponding to each vibrational energy become sharper, but broad peaks reflect disordered crystallinity (promotion of amorphous structure). Furthermore, since the wavelength difference between the Raman scattered light and the incident light corresponds to a portion of the vibrational energy possessed by the substance, Raman spectra reflect information about molecular structure and differences in crystal structure. The inventors conducted in-depth research and discovered that the characteristics of Raman spectra are related to rate characteristics without changing the composition of the solid electrolyte, leading to the present invention.

[0047] In the solid electrolyte of this embodiment, the Raman spectrum measured at an excitation wavelength of 532 nm is in the range of 900–1250 cm⁻¹. -1 It has two or more peaks, peak a and peak b, with peak a ranging from 950 to 1025 cm. -1 The range has a peak, with peak b ranging from 1026 to 1110 cm. -1 The range has a peak. Although not determined, it is preferred from the viewpoint that a composition having two or more peaks forms a conduction path that is less likely to confine lithium ions. This can suppress locally inhomogeneous electrochemical reactions, thus improving the rate characteristics of the solid electrolyte battery.

[0048] In the solid electrolyte of this embodiment, the Raman spectrum measured at an excitation wavelength of 532 nm is used to link the 900-1250 cm⁻¹ of the Raman spectrum.-1 Using the straight line as the baseline, when the intensities of peaks a and b are set to Ia and Ib respectively, Ia > Ib. Although not definitively determined, it is preferred from the viewpoint that by setting a composition with two or more peaks and satisfying the peak intensity relationship, a conduction path that is less likely to confine lithium ions can be formed. This further suppresses locally inhomogeneous electrochemical reactions, thus further improving the rate characteristics of the solid electrolyte battery.

[0049] The solid electrolyte of this embodiment preferably has peaks at 170 ± 0.5 eV (for sulfur in the chemical state corresponding to SO4) and 532 ± 0.5 eV (for oxygen in the chemical state corresponding to SO4) in X-ray photoelectron spectrometry (XPS).

[0050] This is preferred from the viewpoint that the SO4 structure is maintained within the solid electrolyte material by the strong bonding of sulfur and oxygen in the solid electrolyte, thus forming a conduction pathway that does not easily confine lithium ions. It can suppress locally inhomogeneous electrochemical reactions, thereby improving the rate characteristics of the solid electrolyte battery.

[0051] Solid electrolyte battery

[0052] Figure 4 This is a cross-sectional schematic diagram of the solid electrolyte battery 100 according to this embodiment. Figure 4 The solid electrolyte battery 100 shown includes a power generation element 40 and an outer casing 50. The outer casing 50 covers the area surrounding the power generation element 40. The power generation element 40 is connected to the outside via a pair of connected terminals 60, 62. Figure 4 The image shows a stacked battery, but it can also be a wound battery. The solid electrolyte battery 100 is used in, for example, laminated batteries, prismatic batteries, cylindrical batteries, coin-shaped batteries, button batteries, etc.

[0053] <Power Generation Components>

[0054] The power generation element 40 includes a solid electrolyte layer 10, a positive electrode 20, and a negative electrode 30. The power generation element 40 is charged or discharged between the positive electrode 20 and the negative electrode 30 by the acceptance and donation of ions through the solid electrolyte layer 10 and the acceptance and donation of electrons through the external circuit.

[0055] (Solid electrolyte layer)

[0056] The solid electrolyte layer 10 is a layer containing the solid electrolyte of this embodiment. The solid electrolyte layer 10 may be only the solid electrolyte of this embodiment, but it may also be used in conjunction with a support such as an adhesive or nonwoven fabric. The adhesive can be the same material used for the electrode. From the viewpoint of not hindering lithium-ion conduction, the ratio of the solid electrolyte to the solid electrolyte is preferably less than 30% by volume. From the viewpoint of suppressing localized uneven electrochemical reactions caused by cracks, etc., a support such as nonwoven fabric may also be used. The material of the support such as nonwoven fabric is only required to be insulating, such as resin, ceramic, or glass used for the adhesive, and the opening ratio is preferably 85% or more.

[0057] The solid electrolyte layer 10 is sandwiched between a positive electrode 20 and a negative electrode 30. The solid electrolyte layer 10 contains a solid electrolyte that enables ion movement by an externally applied voltage. For example, the solid electrolyte conducts lithium ions and impedes the movement of electrons.

[0058] The solid electrolyte layer 10 may be composed solely of the solid electrolyte of this embodiment, or it may be used in conjunction with other solid electrolytes as needed. They may be used in combination or as two or more layers. Here, other solid electrolytes are electrolytes that conduct lithium ions and impede electron movement, such as oxide-based solid electrolytes, halide-based solid electrolytes, sulfide-based solid electrolytes, complex hydride-based solid electrolytes, and ionically conductive polymers.

[0059] The solid electrolyte layer 10 contains, for example, the solid electrolyte described above. The solid electrolyte contained in the positive electrode 20 or negative electrode 30 may be the same as or different from the solid electrolyte described above.

[0060] (positive electrode)

[0061] like Figure 4 As shown, the positive electrode 20 has a plate-shaped (foil-shaped) positive current collector 22 and a positive electrode flux layer 24. The positive electrode flux layer 24 is in contact with at least one side of the positive current collector 22.

[0062] The positive current collector 22 can be made of an electronically conductive material that is resistant to oxidation during charging and does not easily corrode. Examples of positive current collector 22 include metals such as aluminum, stainless steel, nickel, and titanium, their alloys, and conductive resins. The positive current collector 22 can also be in various forms such as powder, foil, perforated product, or ductile product.

[0063] The positive electrode layer 24 contains positive electrode active material and, if necessary, contains solid electrolyte, binder and conductive additive.

[0064] There are no particular limitations on the positive electrode active material, as long as it can reversibly perform lithium ion absorption, release, insertion, and deintercalation (intercalation and deintercalation), and any known positive electrode active material used in solid electrolyte batteries can be used. Examples of positive electrode active materials include lithium-containing metal oxides and lithium-containing metal phosphates.

[0065] Lithium-containing metal oxides include, for example, lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium manganese spinel (LiMn2O4), and those with the general formula: LiNi x Co y Mn z O2 (x + y + z = 1) represents composite metal oxides, lithium vanadium compounds (LiVOPO4, Li3V2(PO4)3), olivine-type LiMPO4 (where M represents at least one selected from Co, Ni, Mn, and Fe), and lithium titanate (Li4Ti5O) 12 )wait.

[0066] Alternatively, the positive electrode active material may also be lithium-free. Examples of such positive electrode active materials include lithium-free metal oxides (MnO2, V2O5, etc.), lithium-free metal sulfides (MoS2, etc.), and lithium-free fluorides (FeF3, VF3, etc.). When using a lithium-free positive electrode active material, lithium ions are pre-doped into the negative electrode, or a negative electrode containing lithium ions is used.

[0067] The solid electrolyte contained in the positive electrode 20 is, for example, the solid electrolyte described above. The solid electrolyte contained in the positive electrode 20 may also be a halide-based solid electrolyte other than the solid electrolyte described above.

[0068] The content of solid electrolyte in the positive electrode mixture layer 24 is not particularly limited, but is preferably 1% to 50% by mass, more preferably 5% to 30% by mass, based on the total mass of the positive electrode active material, solid electrolyte, conductive additive and binder.

[0069] An adhesive binds the positive electrode active material, solid electrolyte, and conductive additives together within the positive electrode compound layer 24, and firmly bonds the positive electrode compound layer 24 and the positive electrode current collector 22. The positive electrode compound layer 24 preferably contains an adhesive. The adhesive preferably has antioxidant properties and good adhesion.

[0070] Examples of adhesives used for the positive electrode binder layer 24 include polyvinylidene fluoride (PVDF) or copolymers thereof, polytetrafluoroethylene (PTFE), polyamide (PA), polyimide (PI), polyamide-imide (PAI), polybenzimidazole (PBI), polyethersulfone (PES), polyacrylic acid (PA) and copolymers thereof, metal ion crosslinkers of polyacrylic acid (PA) and copolymers thereof, polypropylene (PP) grafted with maleic anhydride, polyethylene (PE) grafted with maleic anhydride, or mixtures thereof. Alternatively, conductive polymers with electronic conductivity or ionic conductivity can be used as bonding materials. Examples of conductive polymers with electronic conductivity include polyacetylene. In this case, the bonding material functions as conductive additive particles; therefore, conductive additives may not be added. Examples of ionically conductive polymers, such as those capable of conducting lithium ions, include those formed by combining monomers of polymers (polyether-based polymers such as polyethylene oxide and polypropylene oxide, polyphosphononitriles, etc.) with lithium salts such as LiClO4, LiBF4, LiPF6, LiTFSI, and LiFSI, or lithium-based alkali metal salts. Polymerization initiators suitable for these composites include photopolymerization initiators or thermal polymerization initiators appropriate to the aforementioned monomers. As for the properties required of adhesive materials, examples include those exhibiting oxidation-reduction resistance and good adhesion.

[0071] The content of the binder in the positive electrode binder layer 24 is not particularly limited, but is preferably 1% to 15% by mass, more preferably 3% to 5% by mass, based on the total mass of the positive electrode active material, solid electrolyte, conductive additive, and binder. If the amount of binder is too small, the positive electrode 20 will not be able to form sufficient adhesive strength. Conversely, if the amount of binder is too large, ordinary binders are electrochemically inert, and therefore do not contribute to the discharge capacity, making it difficult to obtain sufficient volumetric or gravimetric energy density.

[0072] The conductive additive improves the electronic conductivity of the positive electrode layer 24. Known conductive additives can be used. Examples of conductive additives include carbon materials such as carbon black, graphite, carbon nanotubes, and graphene; metals such as aluminum, copper, nickel, stainless steel, iron, and amorphous metals; conductive oxides such as ITO; or mixtures thereof. Conductive additives can also be in various forms, such as powders or fibers.

[0073] The content of conductive additives in the positive electrode binder layer 24 is not particularly limited. When conductive additives are added, the mass ratio of conductive additives is preferably 0.5% to 20% by mass, more preferably 1% to 5% by mass, based on the total mass of the positive electrode active material, solid electrolyte, conductive additives and binder.

[0074] (negative electrode)

[0075] like Figure 4 As shown, the negative electrode 30 has a negative electrode current collector 32 and a negative electrode flux layer 34. The negative electrode flux layer 34 is connected to the negative electrode current collector 32.

[0076] The negative current collector 32 only needs to be electrically conductive. For example, the negative current collector 32 can be metals such as copper, aluminum, nickel, stainless steel, iron, and their alloys, or conductive resins. The negative current collector 32 can also be in various forms such as powder, foil, perforated product, or extended product.

[0077] The negative electrode mixture layer 34 contains negative electrode active material and, as needed, contains solid electrolyte, binder and conductive additive.

[0078] The negative electrode active material only needs to be able to reversibly absorb and release lithium ions, and insert and detach lithium ions; there are no particular limitations. The negative electrode active material can be any material known to be used in solid electrolyte batteries.

[0079] Negative electrode active materials include, for example, natural graphite, artificial graphite, mesophase carbon microspheres, mesophase carbon fiber (MCF), coke, glassy carbon, sintered organic compounds, and other carbon materials, as well as Si and SiO. x Metals such as Sn and aluminum that can combine with lithium, their alloys, composite materials of these metals and carbon materials, and lithium titanate (Li₄Ti₅O₂). 12 Oxides such as SnO2 and metallic lithium are used. Natural graphite is preferred as the negative electrode active material.

[0080] The solid electrolyte contained in the negative electrode 30 is, for example, the solid electrolyte described above. The solid electrolyte contained in the negative electrode 30 may also be a halide-based solid electrolyte other than the solid electrolyte described above.

[0081] The binder and conductive additives contained in the negative electrode 30 may be the same substances as those contained in the positive electrode 20, or they may be different substances.

[0082] <Exterior body>

[0083] The outer casing 50 houses the power generation element 40. The outer casing 50 prevents moisture and other contaminants from entering the interior. For example... Figure 4 As shown, the outer casing 50 has a metal foil 52 and a resin layer 54 laminated on each side of the metal foil 52. The outer casing 50 is a metal laminate formed by coating the metal foil 52 from both sides using the resin layer 54.

[0084] The metal foil 52 can be, for example, aluminum foil or stainless steel foil. The resin layer 54 can be, for example, a resin film such as polypropylene. The materials constituting the resin layer 54 can also be different on the inner and outer sides. For example, as the outer material, a high-melting-point polymer can be used, such as polyethylene terephthalate (PET) or polyamide (PA); as the inner material, polyethylene (PE) or polypropylene (PP) can be used.

[0085] <Terminal>

[0086] Terminals 60 and 62 are connected to the positive terminal 20 and the negative terminal 30, respectively. Terminal 60, connected to the positive terminal 20, is the positive terminal, and terminal 62, connected to the negative terminal 30, is the negative terminal. Terminals 60 and 62 provide electrical connection to the external environment. Terminals 60 and 62 are made of conductive materials such as aluminum, nickel, or copper. The connection method can be welding or threaded fixing. To prevent short circuits, terminals 60 and 62 are preferably protected with insulating tape.

[0087] "Methods for manufacturing solid electrolytes"

[0088] Next, the manufacturing method of the solid electrolyte battery of this embodiment will be described.

[0089] The method for manufacturing a solid electrolyte represented by formula (1) will be described. The solid electrolyte is obtained by mixing raw material powders in a specified molar ratio and reacting them to achieve the desired composition. There are no restrictions on the method of reaction, and mechanical chemical milling, sintering, melting, liquid phase, solid phase and other methods can be used.

[0090] Solid electrolytes can be manufactured, for example, by mechanochemical milling. First, a planetary ball mill apparatus is prepared. A planetary ball mill apparatus is a device that feeds media (hard balls used to promote crushing or mechanochemical reactions) and materials into a dedicated container, and allows the materials to rotate and revolve, thereby crushing the materials or causing mechanochemical reactions between the materials.

[0091] A solid electrolyte is prepared, for example, in a glove box circulated with argon gas, in a container made of zirconia, with a specified amount of zirconia spheres. From the viewpoint of stably synthesizing the target compound, the dew point inside the glove box is preferably set to below -30°C and above -90°C.

[0092] Next, the specified raw materials are prepared in a zirconia container at a specified molar ratio to achieve the desired composition, and the container is sealed with a zirconia lid. The raw materials can be powder or liquid. Then, a mechanochemical milling process is performed for a specified time at specified rotational and revolution speeds, thereby inducing a mechanochemical reaction. This method yields a powdered solid electrolyte composed of a compound having the desired composition. If this synthesis can be performed, there are no limitations on the adjustment methods; heating and cooling can also be performed during the synthesis.

[0093] When the raw material powder contains halide raw materials, the halide raw materials tend to evaporate when the temperature is increased. Therefore, halogen gases can be coexisted in the sintering atmosphere to replenish the halogen. Alternatively, when the halide raw materials are present in the raw material powder, sintering can be performed using a highly airtight mold via hot pressing. In this case, the high airtightness of the mold suppresses the evaporation of the halide raw materials caused by sintering. Through this sintering process, a solid electrolyte in the form of a sintered body composed of compounds with a specified composition is obtained.

[0094] Preparation of the mixture for the positive electrode layer

[0095] Prepare a mixture for the positive electrode layer containing the positive electrode active material and conductive additive. There are no restrictions on the method if uniform mixing is possible; dry mixing, wet mixing, etc., can be used. A binder or the solid electrolyte described above can also be mixed into the above-mentioned positive electrode mixture.

[0096] Preparation of the mixture for the negative electrode binder layer

[0097] Prepare a mixture for the negative electrode layer, which contains the negative electrode active material and conductive additive. There are no restrictions on the method as long as uniform mixing is achieved; dry mixing, wet mixing, etc., can be used. A binder or the aforementioned solid electrolyte can also be mixed into the above-mentioned negative electrode mixture.

[0098] "Manufacturing Method of Power Generation Components"

[0099] Next, the manufacturing method of the power generation element 40 of this embodiment will be described. The power generation element 40 of this embodiment is manufactured, for example, using a powder molding method. The powder molding method is performed in an environment with a dew point below -20°C and above -90°C. For example, the dew point inside the glove box is adjusted.

[0100] First, prepare a resin support with a central through-hole, a lower punch, and an upper punch. For better formability, a metal support made of mold steel can be used instead of the resin support. The diameter of the through-hole in the resin support is, for example, 10 mm, and the diameters of the lower and upper punches are, for example, 9.99 mm. Insert the lower punch below the through-hole in the resin support, and feed powdered solid electrolyte into the resin support through its opening. Next, insert the upper punch onto the fed powdered solid electrolyte and place the container on a press for stamping. The stamping pressure is, for example, 373 MPa. The powdered solid electrolyte, formed by stamping within the resin support using the upper and lower punches, becomes a solid electrolyte layer 10.

[0101] Next, the upper punch is temporarily removed, and the mixture for the positive electrode active material layer is added to the upper punch side of the solid electrolyte layer 10. Then, the upper punch is reinserted for stamping. The stamping pressure is set to, for example, 373 MPa. The positive electrode mixture layer 24 is formed through stamping.

[0102] Next, the lower punch is temporarily removed, and the mixture for the negative electrode active material layer is added to the lower punch side of the solid electrolyte layer 10. For example, the sample is inverted so that it faces the positive electrode active material layer 24, and the material of the mixture for the negative electrode active material layer is added on top of the solid electrolyte layer 10. Then, the lower punch is inserted again for stamping. The stamping pressure is set to, for example, 373 MPa. The mixture for the negative electrode active material layer becomes the negative electrode active material layer 34 through stamping.

[0103] Next, the upper punch is removed once, and the positive current collector 22 and the upper punch are sequentially inserted onto the positive electrode active material layer 24. Then, the lower punch is removed once, and the negative electrode current collector 32 and the lower punch are sequentially inserted onto the negative electrode active material layer 34. The positive electrode current collector 22 and the negative electrode current collector 32 are, for example, aluminum foil or copper foil with a diameter of 10 mm. Through the above sequence, the positive electrode current collector 22 / positive electrode active material layer 24 / solid electrolyte layer 10 / negative electrode active material layer 34 / negative electrode current collector 32, and the power generation element 40 of this embodiment, are obtained.

[0104] Depending on the requirements, the power generation element 40 can also utilize stainless steel circular plates and bakelite circular plates with threaded holes at four locations, loaded in the following order: stainless steel circular plate / bakelite circular plate / upper punch / power generation element 40 / lower punch / bakelite circular plate / stainless steel circular plate, and the screws at the four locations are tightened. From the viewpoint of improving the engagement between the upper punch and the positive current collector 22, the positive current collector 22 and the positive active material 24, the lower punch and the negative current collector 32, and the negative current collector 32 and the negative active material 34, the power generation element 40 can also be a similar mechanism with such conformal function.

[0105] - Storage process -

[0106] The storage process is carried out, for example, in a glove box where argon gas is circulated. The dew point inside the glove box is set to be below -20°C and above -90°C. Preferably, the dew point inside the glove box is below -30°C and above -85°C.

[0107] Screws are inserted into the threaded holes on the sides of the upper and lower punches, and then inserted into the outer casing where external terminals are mounted. The screws and external terminals on the sides of the upper and lower punches are connected using leads or the like. The casing is then housed within the outer casing 50 and sealed by heat sealing the opening of the outer casing 50. Through the above processes, the solid electrolyte battery of this embodiment is obtained.

[0108] The solid electrolyte battery 100 of this embodiment contains the above-described solid electrolyte, thus forming a conduction path that is not easily constrained by lithium ions, which can suppress localized non-uniform electrochemical reactions, thereby improving the rate characteristics of the solid electrolyte battery.

[0109] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, each structure and combination thereof in each embodiment is an example, and structural additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention.

[0110] Example

[0111] Example 1

[0112] (Preparation of solid electrolytes)

[0113] In a glove box with a dew point of approximately -75°C, zirconium chloride (ZrCl4) and lithium sulfate (Li2SO4) powders were weighed in a 1:1 molar ratio and added to a zirconia-based sealed container for a planetary ball mill, which had been pre-loaded with zirconia balls and dried under the same conditions. The sealed container was then fitted with the lid threaded onto the container body, and polyimide tape was used to seal the lid and the sealed container. The zirconia balls, the zirconia-based sealed container for the planetary ball mill, and the lid were pre-dried under reduced pressure at 80°C and then allowed to return to room temperature before use. Ar gas (G1 grade, manufactured by Taiyo Nippon Sanso) was used to restore atmospheric pressure. The polyimide tape provided a moisture barrier. The zirconia-based sealed container was then placed on a planetary ball mill and subjected to a mechanochemical reaction at 300 rpm for 5 hours to synthesize a solid electrolyte (Li2Zr(SO4)Cl4). The rotation-to-revolution ratio was set to 1:1. In addition, the synthesis begins after cooling the sealed container and lid made of zirconium oxide to a temperature below 10°C, and the synthesis is carried out while cooling is being performed.

[0114] Planetary ball mills are typically installed in an atmosphere. The zirconia sealed container used in planetary ball mills is threaded in place and further sealed with polyimide tape. When the zirconia sealed container is placed in the planetary ball mill, because the structure of the zirconia sealed container is firmly pressed and fixed from the cover side, it becomes a structure without a released cover. It is assumed that even in a normal atmosphere, moisture will hardly mix into the zirconia sealed container from the atmosphere.

[0115] <Determination of Raman Spectroscopy>

[0116] The Raman spectrum of the solid electrolyte of Example 1 was determined by Raman spectrophotometry.

[0117] Sampling was performed in a glove box with an argon gas circulation dew point of approximately -70°C, and the sample was transported to a Raman spectrometer (Japan Spectrophotometer: NRS-7100) for measurement under atmospheric non-exposed conditions.

[0118] Regarding the Raman spectroscopy measurement conditions, the laser wavelength was 532 nm, the slit width was 100 × 1000 μm, the aperture was 40 μm, the exposure time was 60 seconds, and the cumulative exposure was twice.

[0119] The obtained Raman spectrum is in the range of 900-1250 cm⁻¹ -1 In the middle, it was confirmed that the range was 950–1025 cm. -1 The range includes peak a at the apex and peaks in the range of 1026–1110 cm. -1 The range has peak b at the apex. Connecting these peaks yields the Raman spectrum from 900 to 1250 cm⁻¹. -1 Using the straight line as the baseline, the intensities Ia and Ib of each peak were measured.

[0120] exist Figure 1 The figure shows the Raman spectrum of Example 1 that was measured.

[0121] <XPS Measurement>

[0122] In addition, X-ray photoelectron spectroscopy was performed on the solid electrolyte of Example 1. Sampling was conducted in a glove box with an argon gas circulation system and a dew point of approximately -70°C, and transported to the XPS apparatus under atmospheric non-exposure conditions. XPS measurements were performed using a Quantera2 from PHI Corporation. The results showed peaks at 170 ± 0.5 eV and 532 ± 0.5 eV for the prepared solid electrolyte.

[0123] - Mixing of positive electrode agents -

[0124] Next, the positive electrode mixture was weighed and mixed in a glove box with an argon gas circulation system and a dew point of -75°C. The mixture was weighed in a ratio of lithium cobalt oxide (LiCoO2):Li2Zr(SO4)Cl4:carbon black = 75:19:6 parts by weight, and mixed in an agate mortar for 5 minutes to obtain the positive electrode mixture. The agate mortar, lithium cobalt oxide, carbon black, and zirconium oxide sealed container used for mixing were similarly subjected to reduced pressure drying before use. Lithium cobalt oxide with an average particle size of 7.5 μm was used.

[0125] -Preparation of negative electrode compound-

[0126] Next, the negative electrode mixture was weighed and mixed in a glove box with an argon gas circulation system and a dew point of -75°C. This mixture was used to prepare lithium titanate (Li4Ti5O4). 12The following mixture was weighed in parts by weight:Li₂Zr(SO₄)Cl₄:carbon black = 72:22:6, and mixed in an agate mortar for 5 minutes to obtain the negative electrode mixture. The agate mortar, lithium titanate, carbon black, and zirconium oxide were similarly dried under reduced pressure in a sealed container before use. Lithium titanate with an average particle size of 6.0 μm was used.

[0127] (Fabrication of solid electrolyte batteries)

[0128] Solid electrolyte batteries are manufactured in a glove box at a dew point of approximately -75°C. The solid electrolyte batteries are fabricated using a pelletizing fixture. The pelletizing fixture has a 10mm inner diameter PEEK (polyetheretherketone) support and upper and lower punches with a diameter of 9.99mm. The upper and lower punches are made of die steel (SKD11 material).

[0129] A lower punch was inserted into the PEEK support of the granulation fixture, and 50 mg of solid electrolyte was added on top of the lower punch. Then, the resin support was vibrated to homogenize the surface of the solid electrolyte, and an upper punch was inserted on top of the solid electrolyte. The granulation was then performed using a press with an additional weight of approximately 4 kN.

[0130] Next, pull out the lower punch and add 10mg of negative electrode binder on top of the solid electrolyte. Then, vibrate the PEEK support to homogenize the surface of the negative electrode binder, insert the lower punch on top of the negative electrode binder, and use a punching machine to punch with a 3KN weight.

[0131] Next, the upper punch is removed, and 12 mg of positive electrode binder is added on top of the solid electrolyte layer. Then, the PEEK support is vibrated to homogenize the surface of the positive electrode binder. The upper punch is then inserted on top of the positive electrode binder, and a punching machine is used to press it with a 3 kN weight.

[0132] Next, the upper punch is removed once, and the positive current collector (aluminum foil, 10mm in diameter, 20µm thick) and the upper punch are inserted sequentially on top of the positive electrode flux layer. Then, the lower punch is removed once, and the negative current collector (copper foil, 10mm in diameter, 10µm thick) and the lower punch are inserted sequentially on top of the negative electrode flux layer. This creates a power generation element composed of a positive current collector, a positive electrode flux layer, a solid electrolyte layer, a negative electrode flux layer, and a negative current collector.

[0133] Prepare stainless steel and Bakelite (registered trademark) round plates, each 50mm in diameter and 5mm thick, with threaded holes at four locations. Assemble the generator element as follows: Load the components in the following order: stainless steel round plate / Bakelite round plate / upper punch / generator element / lower punch / Bakelite round plate / stainless steel round plate. Tighten the screws at the four locations with a torque of 1 N·m to create the generator element unit. Additionally, insert screws for external terminal connections into the threaded holes on the sides of the upper and lower punches.

[0134] Next, an A4-sized aluminum laminated bag was prepared as the outer casing for the encapsulated power generation element unit. On one side of the opening of the aluminum laminated bag, as external terminals, aluminum foil (4mm wide, 40mm long, 100μm thick) and nickel foil (4mm wide, 40mm long, 100μm thick) wrapped with maleic anhydride-grafted polypropylene (PP) were thermally bonded at intervals to prevent short circuits. The power generation element unit was inserted into the aluminum laminated bag with the external terminals installed. Leads were used to connect the screws on the upper punch side to the aluminum terminals extending into the outer casing, and the screws on the lower punch side to the nickel terminals extending into the outer casing. Finally, the opening was heat-sealed to fabricate a solid electrolyte battery. The fabricated solid electrolyte battery was then placed in a constant temperature bath at 25°C for 48 hours to stabilize the open-circuit voltage.

[0135] The rate characteristics were evaluated using the fabricated solid electrolyte battery. The rate characteristics were evaluated based on the ratio of the discharge capacity (Cap1C) to the charge capacity (Cap0.1C) at a discharge rate of 0.5C (Cap0.5C / Cap0.1C).

[0136] The solid electrolyte battery was constant-current charged at a rate of 0.1C (CC charging) at 25°C until a battery voltage of 2.7V was reached. After reaching 2.7V, it was then charged (CV charging) until a current equivalent to 0.05C was achieved, and the charge capacity at 0.1C (Cap0.1C) was measured. Then, it was discharged at a constant current rate of 0.5C (CC discharging) until a battery voltage of 1.5V was achieved, and the discharge capacity at 0.5C (Cap0.5C) was measured. The measurement results are summarized in Tables 3 and 4.

[0137] Example 2

[0138] Example 2, except for a change in synthesis time, synthesized a solid electrolyte in the same manner as in Example 1, and performed Raman analysis and rate characteristic evaluation. Figure 2 The measured Raman spectra are shown below. The measurement results are summarized in Tables 3 and 4.

[0139] Examples 3-30

[0140] Examples 3-30, except for changes in raw materials and / or molar ratios and synthesis time, synthesized solid electrolytes in the same manner as in Example 1, and underwent Raman analysis and rate characteristic evaluation. The results are summarized in Tables 1, 2, 3, and 4.

[0141] Example 31

[0142] Example 31 synthesized a solid electrolyte in the same manner as Example 1, except for a change in the synthesis time. Raman analysis and rate characteristic evaluation were then performed. The results are summarized in Tables 5 and 6.

[0143] Comparative Example 1

[0144] Comparative Example 1, except for a change in synthesis time, synthesized a solid electrolyte in the same manner as in Example 1, and underwent Raman analysis and rate characteristic evaluation. Figure 3 The measured Raman spectra are shown below. The measurement results are summarized in Tables 3 and 4.

[0145] Comparative Examples 1-15

[0146] Comparative Examples 1-15 were synthesized in the same manner as in Example 1, except for changes in the raw materials and / or molar ratios and the synthesis time. Raman analysis and rate characteristic evaluation were performed. The results are summarized in Tables 1, 2, 3, and 4.

[0147] Comparative Example 16

[0148] Comparative Example 16 synthesized a solid electrolyte in the same manner as in Example 31, except that cooling was not performed, and Raman analysis and rate characteristic evaluation were performed. The results are summarized in Tables 5 and 6.

[0149] [Table 1]

[0150]

[0151] [Table 2]

[0152]

[0153] [Table 3]

[0154]

[0155] [Table 4]

[0156]

[0157] [Table 5]

[0158]

[0159] [Table 6]

[0160]

[0161] Example 1 and Example 2, as well as Comparative Example 1, had the same composition, but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 1 and 2, but peak b was not confirmed in Comparative Example 1. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 1, and Ia < Ib in Example 2. In terms of rate characteristics, Example 1 was the best, followed by Example 2, and finally Comparative Example 1. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0162] Example 3 and Example 4, as well as Comparative Example 2, had the same composition but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 3 and 4, but peak b was not confirmed in Comparative Example 2. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 3, and Ia < Ib in Example 4. In terms of rate characteristics, Example 3 was the best, followed by Example 4, and finally Comparative Example 2. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0163] Example 5 and Example 6, as well as Comparative Example 3, had the same composition but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 5 and 6, but peak b was not confirmed in Comparative Example 3. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 5, and Ia < Ib in Example 6. In terms of rate characteristics, Example 5 was the best, followed by Example 6, and finally Comparative Example 3. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0164] Example 7 and Example 8, as well as Comparative Example 4, had the same composition, but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 7 and 8, but peak b was not confirmed in Comparative Example 4. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 7, and Ia < Ib in Example 8. In terms of rate characteristics, Example 7 was the best, followed by Example 8, and finally Comparative Example 4. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0165] Example 9 and Examples 10 and Comparative Example 5 had the same composition, but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 9 and 10, but peak b was not confirmed in Comparative Example 5. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 9, and Ia < Ib in Example 10. In terms of rate characteristics, Example 9 was the best, followed by Example 10, and finally Comparative Example 5. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0166] Example 11 and Example 12, as well as Comparative Example 6, have the same composition, but different synthesis times. Accordingly, in the Raman spectra, peaks a and b were confirmed in Examples 11 and 12, but peak b was not confirmed in Comparative Example 6. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 11, while Ia < Ib in Example 12. In terms of rate characteristics, Example 11 is the best, followed by Example 12, and finally Comparative Example 6. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0167] Example 13 and Example 14, as well as Comparative Example 7, had the same composition, but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 13 and 14, but peak b was not confirmed in Comparative Example 7. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 13, and Ia < Ib in Example 14. In terms of rate characteristics, Example 13 was the best, followed by Example 14, and finally Comparative Example 7. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0168] Example 15 and Example 16, as well as Comparative Example 8, had the same composition, but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 15 and 16, but peak b was not confirmed in Comparative Example 8. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 15, and Ia < Ib in Example 16. In terms of rate characteristics, Example 15 was the best, followed by Example 16, and finally Comparative Example 8. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0169] Example 17 and Example 18, as well as Comparative Example 9, have the same composition, but different synthesis times. Accordingly, in the Raman spectra, peaks a and b were confirmed in Examples 17 and 18, but peak b was not confirmed in Comparative Example 9. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 17, and Ia < Ib in Example 18. In terms of rate characteristics, Example 17 is the best, followed by Example 18, and finally Comparative Example 9. As described above, even with the same composition, rate characteristics can be improved by adjusting it in a manner that produces a defined Raman spectrum.

[0170] Example 19 and Examples 20 and Comparative Example 10 have the same composition, but different synthesis times. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 19 and 20, but peak b was not confirmed in Comparative Example 10. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 19, and Ia < Ib in Example 20. In terms of rate characteristics, Example 19 is the best, followed by Example 20, and finally Comparative Example 10. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0171] Example 21 and Example 22, as well as Comparative Example 11, have the same composition, but different synthesis times. Accordingly, in the Raman spectra, peaks a and b were confirmed in Examples 21 and 22, but peak b was not confirmed in Comparative Example 11. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 21, and Ia < Ib in Example 22. In terms of rate characteristics, Example 21 is the best, followed by Example 22, and finally Comparative Example 11. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0172] Example 23 and Example 24, as well as Comparative Example 12, have the same composition, but different synthesis times. Accordingly, in the Raman spectra, peaks a and b were confirmed in Examples 23 and 24, but peak b was not confirmed in Comparative Example 12. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 23, while Ia < Ib in Example 24. In terms of rate characteristics, Example 23 is the best, followed by Example 24, and finally Comparative Example 12. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0173] Example 25 and Example 26, as well as Comparative Example 13, have the same composition, but different synthesis times. Accordingly, in the Raman spectra, peaks a and b were confirmed in Examples 25 and 26, but peak b was not confirmed in Comparative Example 13. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 25, and Ia < Ib in Example 26. In terms of rate characteristics, Example 25 is the best, followed by Example 26, and finally Comparative Example 13. As described above, even with the same composition, rate characteristics can be improved by adjusting it in a manner that produces a defined Raman spectrum.

[0174] Example 27 and Example 28, as well as Comparative Example 14, have the same composition, but different synthesis times. Accordingly, in the Raman spectra, peaks a and b were confirmed in Examples 27 and 28, but peak b was not confirmed in Comparative Example 14. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Example 27, and Ia < Ib in Example 28. In terms of rate characteristics, Example 27 is the best, followed by Example 28, and finally Comparative Example 14. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0175] Example 29 has the same composition as Example 30 and Comparative Example 15, but the synthesis time is different. Accordingly, in the Raman spectra, peaks a and b were confirmed in Examples 29 and 30, but peak b was not confirmed in Comparative Example 15. Furthermore, differences were also confirmed in peak intensities Ia and Ib; in Example 29, Ia > Ib, while in Example 30, Ia < Ib. In terms of rate characteristics, Example 29 is the best, followed by Example 30, and finally Comparative Example 15. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0176] Example 1 has the same composition as Examples 2, 31, and Comparative Example 1, but the synthesis time is different. Accordingly, peaks a and b were confirmed in the Raman spectra of Examples 1, 2, and 31, but peak b was not confirmed in Comparative Example 1. Furthermore, differences were also confirmed in peak intensities Ia and Ib: Ia > Ib in Examples 1 and 31, and Ia < Ib in Example 2. In terms of rate characteristics, Example 1 is the best, followed by Example 31, then Example 2, and finally Comparative Example 1. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0177] Example 31 and Comparative Example 16 had the same composition and synthesis time, but differed in the presence or absence of cooling during synthesis. Accordingly, in the Raman spectra, peaks a and b were confirmed in Example 31, with peak intensities Ia and Ib respectively, where Ia > Ib. In Comparative Example 16, peak a was not clearly identified, and when the intensity of the Raman spectrum near it was assumed to be Ia, Ia < Ib. Regarding the various rate characteristics, the results of Example 31 were better than those of Comparative Example 16. As described above, even with the same composition, rate characteristics can be improved by adjusting the composition to achieve a predetermined Raman spectrum.

[0178] Industrial availability

[0179] It can provide a solid electrolyte that can improve rate characteristics, a solid electrolyte layer using the solid electrolyte, and a solid electrolyte battery.

[0180] Explanation of reference numerals in the attached figures

[0181] 10… Solid electrolyte layer, 20… Positive electrode, 22… Positive current collector, 24… Positive flux layer, 30… Negative electrode, 32… Negative current collector, 34… Negative flux layer, 40… Power generation element, 50… Outer casing, 52… Metal foil, 54… Resin layer, 60, 62… Terminals, 100… Solid electrolyte battery.

Claims

1. A solid electrolyte characterized by comprising, The solid electrolyte is represented by formula (1), and a Raman spectrum measured at an excitation wavelength of 532 nm has a peak in the range of 900 to 1250 cm -1 -1 has a peak top, and the peak b has a peak top in the range of 1026 to 1110 cm -1 -1 has a peak top, and the peak b has a peak top in the range of 1026 to 1110 cm -1 -1 has a peak top, and the peak b has a peak top in the range of 1026 to 1110 cm Li a A b Zr c B d (SO4) e Cl f X g … (1) in the formula, A is at least one element selected from alkali metals and alkaline earth metals, B is at least one element selected from Na, K, Rb, Cs, Mg, Ca, Sr, Ba, B, Si, Al, Ti, Cu, Sc, Y, Zr, Nb, Ag, In, Sn, Sb, Hf, Ta, W, Au, Bi, X is at least one or more selected from F, Br, I, 0.5≤a<6, 0≤b<6, 0 2. The solid electrolyte according to claim 1, characterized by comprising, The intensity of the peak a and the peak b is respectively set as Ia and Ib, and Ia > Ib, with the straight line of the 900-1250 cm -1 of the connected Raman spectrum as the baseline.

3. A solid electrolyte layer characterized by comprising, the solid electrolyte according to claim 1 or 2.

4. A solid electrolyte battery characterized by comprising, having a solid electrolyte layer, a positive electrode, and a negative electrode, at least one of the positive electrode and the negative electrode comprising the solid electrolyte according to claim 1 or 2.

5. A solid electrolyte battery characterized by comprising, having the solid electrolyte layer according to claim 3, a positive electrode, and a negative electrode.

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