Ion-conducting solid-state and all-solid-state batteries

Abstract

The present invention provides an ion conductive solid which contains an oxide that is represented by general formula Li6+a-c-2dY1-a-b-c-dM1aM2bM3cM4dB3O9. (In the formula, M1 represents at least one metal element that is selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr and Ba; M2 represents at least one metal element that is selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In and Fe, M3 represents at least one metal element that is selected from the group consisting of Hf, Sn and Ti, M4 represents at least one metal element that is selected from the group consisting of Nb and Ta; and a, b, c and d represent real numbers that are respectively within specific ranges, while satisfying 0.010 ≤ a + b + c + d < 1.000.)

Description

[Technical Field]

[0001] The present disclosure relates to ion-conducting solids and all-solid-state batteries. [Background technology]

[0002] BACKGROUND ART Lightweight, high-capacity lithium-ion secondary batteries have conventionally been installed in mobile devices such as smartphones and notebook computers, and in transportation equipment such as electric vehicles and hybrid electric vehicles. However, conventional lithium-ion secondary batteries use a liquid electrolyte containing a flammable solvent, which raises concerns about the risk of the flammable solvent leaking and ignition in the event of a short circuit in the battery. Therefore, in recent years, in order to ensure safety, secondary batteries that use an ion-conductive solid electrolyte, rather than a liquid electrolyte, have been attracting attention. Such secondary batteries are called all-solid-state batteries.

[0003] Widely known solid electrolytes used in all-solid-state batteries include oxide-based solid electrolytes and sulfide-based solid electrolytes. Of these, oxide-based solid electrolytes are safer than sulfide-based solid electrolytes because they do not react with moisture in the air to produce hydrogen sulfide.

[0004] An all-solid-state battery comprises a positive electrode containing a positive electrode active material, a negative electrode containing a negative electrode active material, an electrolyte containing an ion-conductive solid disposed between the positive electrode and the negative electrode, and, optionally, a current collector (the positive electrode active material and the negative electrode active material are collectively referred to as "electrode active material"). When an all-solid-state battery is fabricated using an oxide-based solid electrolyte, a heat treatment is performed to reduce the contact resistance between particles of the oxide-based material contained in the solid electrolyte. However, conventional oxide-based solid electrolytes require high temperatures of 900°C or higher for the heat treatment, which may result in the solid electrolyte reacting with the electrode active material to form a high-resistance phase. This high-resistance phase may reduce the ionic conductivity of the ion-conductive solid and ultimately reduce the output power of the all-solid-state battery. Li is an oxide-based solid electrolyte that can be prepared by heat treatment at temperatures below 900°C. 2+x C1-x B x O3 (Non-Patent Document 1). Also, the above Li 2+x C 1-x B x It has been disclosed that the properties can be improved by adding specific elements to O3 at specific ratios (Patent Document 1). [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Solid State Ionic 288 (2016) 248-252 [Patent documents]

[0006] [Patent Document 1] Patent No. 6948676 Summary of the Invention [Problem to be solved by the invention]

[0007] The present disclosure provides an ion-conductive solid that can be produced by heat treatment at a low temperature and has high ion conductivity, and an all-solid-state battery having the same. [Means for solving the problem]

[0008] The ionically conducting solids of the present disclosure have the general formula Li 6+a-c-2d Y 1-a-b-c-d M1 a M2 b M3 c M4 d It is an ion-conducting solid characterized by containing an oxide represented by B3O9. (In the formula, M1 is at least one metal element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr, and Ba, M2 is at least one metal element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, and Fe; M3 is at least one metal element selected from the group consisting of Hf, Sn, and Ti, and M4 is at least one metal element selected from the group consisting of Nb and Ta, a is a real number that satisfies 0.000≦a≦0.800, b is a real number that satisfies 0.010≦b≦0.900, c is a real number that satisfies 0.000≦c≦0.800, d is a real number that satisfies 0.000≦d≦0.800, and a, b, c, and d are real numbers that satisfies 0.010≦a+b+c+d<1.000.)

[0009] In addition, the all-solid-state battery of the present disclosure includes: A positive electrode and a negative electrode; Electrolytes, An all-solid-state battery having at least The all-solid-state battery is characterized in that at least one selected from the group consisting of the positive electrode, the negative electrode, and the electrolyte contains the ion-conducting solid of the present disclosure. [Effects of the Invention]

[0010] According to one aspect of the present disclosure, it is possible to obtain an ion-conductive solid that can be produced by a heat treatment at a low temperature and has high ion conductivity, and an all-solid-state battery including the ion-conductive solid. DETAILED DESCRIPTION OF THE INVENTION

[0011] In the present disclosure, unless otherwise specified, the expressions "XX or more and YY or less" or "XX to YY" representing a numerical range mean a numerical range including the lower and upper limits, which are the endpoints. When a numerical range is described in stages, the upper and lower limits of each numerical range can be combined in any way. In addition, in the present disclosure, "solid" refers to one of the three states of matter that has a definite shape and volume, and the powder state is included in "solid."

[0012] The ionically conducting solids of the present disclosure have the general formula Li 6+a-c-2d Y 1-a-b-c-dM1 a M2 b M3 c M4 d It is an ionically conductive solid containing an oxide represented by the formula B3O9. In the formula, M1 is at least one metal element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr, and Ba; M2 is at least one metal element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, and Fe; M3 is at least one metal element selected from the group consisting of Hf, Sn, and Ti, and M4 is at least one metal element selected from the group consisting of Nb and Ta, a is a real number that satisfies 0.000≦a≦0.800, b is a real number that satisfies 0.010≦b≦0.900, c is a real number that satisfies 0.000≦c≦0.800, d is a real number that satisfies 0.000≦d≦0.800, and a, b, c, and d are real numbers that satisfies 0.010≦a+b+c+d<1.000.

[0013] The ionically conducting solids of the present disclosure preferably have a monoclinic crystal structure.

[0014] The ion conductive solid of the present disclosure preferably has a volume average particle size of 0.1 μm or more and 28.0 μm or less, more preferably 0.3 μm or more and 26.0 μm or less, and even more preferably 1.0 μm or more and 20.0 μm or less. By having the particle size within the above range, the grain boundary resistance within the ion conductive solid is reduced, and the ion conductivity is further improved. The volume average particle size of the ion-conductive solid can be controlled by pulverization or classification.

[0015] In the above general formula, a is a real number that satisfies 0.000≦a≦0.800. a is 0.000≦a≦0.800, preferably 0.000≦a≦0.600, more preferably 0.000≦a≦0.400, even more preferably 0.000≦a≦0.100, particularly preferably 0.000≦a≦0.050, and extremely preferably 0.000≦a≦0.030.

[0016] In the above general formula, b is a real number that satisfies 0.010≦b≦0.900. b is 0.010≦b≦0.900, preferably 0.020≦b≦0.900, more preferably 0.050≦b≦0.900, even more preferably 0.100≦b≦0.900, particularly preferably 0.200≦b≦0.900, and extremely preferably 0.300≦b≦0.900.

[0017] In the above general formula, c is a real number that satisfies 0.000≦c≦0.800. c is 0.000≦c≦0.800, preferably 0.000≦c≦0.600, more preferably 0.000≦c≦0.400, even more preferably 0.000≦c≦0.100, particularly preferably 0.000≦c≦0.050, and extremely preferably 0.000≦c≦0.030.

[0018] In the above general formula, d is a real number that satisfies 0.000≦d≦0.800. d is 0.000≦d≦0.800, preferably 0.000≦d≦0.600, more preferably 0.000≦d≦0.400, even more preferably 0.000≦d≦0.100, particularly preferably 0.000≦d≦0.050, and extremely preferably 0.000≦d≦0.030.

[0019] In the above formula, a+b+c+d is a real number that satisfies 0.010≦a+b+c+d<1.000. a+b+c+d satisfies 0.010≦a+b+c+d<1.000, preferably 0.050≦a+b+c+d<1.000, more preferably 0.100≦a+b+c+d<1.000, even more preferably 0.200≦a+b+c+d≦1.000, particularly preferably 0.300≦a+b+c+d<1.000, and extremely preferably 0.500≦a+b+c+d<1.000.

[0020] Y 1-a-b-c-dIn the formula, 1-abcd is preferably 0.300≦1-abcd, more preferably 0.500≦1-abcd, even more preferably 0.700≦1-abcd, and even more preferably 0.750≦1-abcd. The upper limit is not particularly limited, but is preferably less than 1.000, 0.950 or less, or 0.900 or less.

[0021] The ion-conducting solid of the present disclosure can have the following embodiments, for example, but is not limited to these embodiments. (1) It is preferable that a satisfy 0.010≦a≦0.100, b satisfy 0.010≦b≦0.200, c satisfy 0.000≦c≦0.200, d satisfy 0.010≦d≦0.100, and a, b, c, and d satisfy 0.010≦a+b+c+d<0.300. (2) It is preferable that a satisfy 0.010≦a≦0.030, b satisfy 0.030≦b≦0.100, c satisfy 0.010≦c≦0.030, d satisfy 0.010≦d≦0.030, and a, b, c, and d satisfy 0.050≦a+b+c+d<0.160. M1, M3, and M4 in the above general formula may or may not be included in the formula. That is, at least one of a, c, and d may be 0.

[0022] In the above general formula, M1 is at least one metal element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr, and Ba. M1 is at least one selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr, and Ba, preferably at least one selected from the group consisting of Mg, Zn, Ca, Sr, and Ba, and more preferably at least one selected from the group consisting of Mg, Ca, and Sr.

[0023] In the above general formula, M2 is at least one metal element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In and Fe. M2 is at least one selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, and Fe, preferably at least one selected from the group consisting of La, Eu, Gd, Tb, Dy, Yb, Lu, In, and Fe, and more preferably at least one selected from the group consisting of Gd, Dy, Yb, Lu, In, and Fe.

[0024] In the above general formula, M3 is at least one metal element selected from the group consisting of Hf, Sn, and Ti. M3 is at least one selected from the group consisting of Hf, Sn and Ti, preferably at least one selected from the group consisting of Hf and Sn, and more preferably Hf.

[0025] In the above general formula, M4 is at least one metal element selected from the group consisting of Nb and Ta. M4 is at least one selected from the group consisting of Nb and Ta, and is preferably Nb.

[0026] The present inventors speculate as follows as to the reason why the ionic conductivity is improved in an ion-conductive solid containing an oxide represented by the above general formula. When a portion of the trivalent metal element Y is replaced with specific elements M1, M2, M3, and M4 in a specific ratio range, the lattice constant and charge balance in the crystal lattice can be adjusted. + When excess or deficiency of Li occurs in the crystal lattice, + The ionic conductivity is improved because the ions move more easily within the crystal lattice. When M1 is used to replace part of Y, Li in the crystal lattice + As a result, there is an excess of Li that can move within the crystal lattice. + Since the amount of ionic conductivity increases, the ionic conductivity improves. When M2 is used to replace part of Y, the crystal lattice becomes smaller by substituting an element with a different ionic radius. + The distance between them becomes shorter, and Li +This promotes the movement of ions and improves ionic conductivity. When M3 or M4 is used to replace a portion of Y, the Li + As a result, Li + The surrounding Li + The ionic conductivity is improved due to the movement of

[0027] Next, a method for producing the ion-conductive solid of the present disclosure will be described. The method for producing an ion-conductive solid according to the present disclosure can be embodied in the following manner, but is not limited thereto. General formula Li 6+a-c-2d Y 1-a-b-c-d M1 a M2 b M3 c M4 d A method for producing an ion-conductive solid containing an oxide represented by B3O9, The method may include a primary firing step in which raw materials mixed so as to obtain an oxide represented by the general formula are heat-treated at a temperature below the melting point of the oxide. In the formula, M1 is at least one metal element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr, and Ba; M2 is at least one metal element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, and Fe; M3 is at least one metal element selected from the group consisting of Hf, Sn, and Ti; M4 is at least one metal element selected from the group consisting of Nb and Ta; a is 0.000≦a≦0.800; b is 0.010≦b≦0.900; c is 0.000≦c≦0.800; d is 0.000≦d≦0.800; and a, b, c, and d are real numbers satisfying 0.010≦a+b+c+d<1.000.

[0028] The method for producing an ion-conductive solid according to the present disclosure can include a primary firing step in which raw materials are weighed and mixed so as to obtain an oxide represented by the above general formula, and the raw materials are heat-treated at a temperature below the melting point of the oxide to produce an ion-conductive solid containing the oxide. The ion-conductive solid can be obtained by the primary firing step. Furthermore, the production method may include, as necessary, a secondary firing step in which the obtained ion-conductive solid containing an oxide is heat-treated at a temperature below the melting point of the oxide to produce a sintered body of the ion-conductive solid containing the oxide. Hereinafter, the method for producing an ion-conductive solid according to the present disclosure, which includes the above-mentioned primary firing step and secondary firing step, will be described in detail, but the present disclosure is not limited to the following production method.

[0029] Primary firing process In the primary firing process, the general formula Li 6+a-c-2d Y 1-a-b-c-d M1 a M2 b M3 c M4 d BO (wherein M1 is one or more metal elements selected from Mg, Mn, Zn, Ni, Ca, Sr, and Ba; M2 is one or more metal elements selected from La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, and Fe; M3 is one or more metal elements selected from Hf, Sn, and Ti; and M4 is one or more metal elements selected from Nb and Ta). The above metallic elements are used, where a is 0.000≦a≦0.800, b is 0.010≦b≦0.900, c is 0.000≦c≦0.800, d is 0.000≦d≦0.800, and a, b, c, and d are real numbers that satisfy 0.010≦a+b+c+d<1.000.) Chemical reagent grade raw materials such as Li3BO3, H3BO3, Yb2O3, ZrO2, CeO2, and HfO2 are weighed out in stoichiometric amounts and mixed to achieve the above formula.

[0030] The equipment used for mixing is not particularly limited, but a pulverizing mixer such as a planetary ball mill can be used. The material and capacity of the container used for mixing, as well as the material and diameter of the balls, are not particularly limited and can be selected appropriately depending on the type and amount of raw materials used. As an example, a 45 mL container made of zirconia and 5 mm diameter zirconia balls can be used. The conditions for the mixing process are not particularly limited, but can be, for example, a rotation speed of 50 rpm to 2000 rpm and a time of 10 to 60 minutes. After obtaining a mixed powder of the raw materials by the mixing process, the mixed powder is press-molded into pellets. As the press-molding method, a known press-molding method such as cold uniaxial pressing or cold isostatic pressing can be used. The press-molding conditions in the primary firing step are not particularly limited, but can be, for example, a pressure of 100 MPa to 200 MPa. The pellets are then calcined using a calciner such as an air calciner. The temperature at which the primary calcination is carried out to perform solid-state synthesis is determined by the general formula Li 6+a-c-2d Y 1-a-b-c-d M1 a M2 b M3 c M4 d There are no particular limitations on the temperature as long as it is below the melting point of the ion-conductive solid represented by B3O9. The temperature during primary firing can be, for example, below 700°C, 680°C or less, 670°C or less, 660°C or less, or 650°C or less, and can be, for example, 500°C or more. The numerical ranges can be combined arbitrarily. A temperature within the above range ensures sufficient solid-phase synthesis. The time for the primary firing step is not particularly limited, but can be, for example, about 700 to 750 minutes. By the primary firing step, the compound of the general formula Li 6+a-c-2d Y 1-a-b-c-d M1 a M2 b M3 c M4 d It is possible to prepare an ion-conductive solid containing an oxide represented by B3O9. The ion-conductive solid containing the oxide can also be pulverized using a mortar and pestle or a planetary mill to obtain a powder of the ion-conductive solid containing the oxide.

[0031] Secondary firing process In the secondary firing step, at least one selected from the group consisting of the ion-conductive solid containing an oxide obtained in the primary firing step and a powder of the ion-conductive solid containing an oxide is pressure-molded as necessary and fired to obtain a sintered body of the ion-conductive solid containing an oxide. The pressure molding and secondary firing may be carried out simultaneously using spark plasma sintering (hereinafter also referred to simply as "SPS") or a hot press, or pellets may be produced by cold uniaxial molding and then secondary firing may be carried out in an air atmosphere, an oxidizing atmosphere, or a reducing atmosphere. Under the above conditions, an ion-conductive solid with high ionic conductivity can be obtained without melting due to heat treatment. The conditions for pressure molding in the secondary firing step are not particularly limited, but can be, for example, a pressure of 10 MPa to 100 MPa. The secondary firing temperature is determined by the general formula Li 6+a-c-2d Y 1-a-b-c-d M1 a M2 b M3 c M4 d The temperature during secondary firing is preferably below the melting point of the ion-conductive solid represented by B3O9. The temperature during secondary firing is preferably below 700°C, more preferably 680°C or less, even more preferably 670°C or less, and particularly preferably 660°C or less. The lower limit of the temperature is not particularly limited, and the lower the better, but it is, for example, 500°C or more. The numerical ranges can be arbitrarily combined, and can be, for example, a range of 500°C or more and less than 700°C. Within the above range, melting or decomposition of the ion-conductive solid containing the oxide of the present disclosure can be suppressed during the secondary firing step, and a sufficiently sintered ion-conductive solid containing the oxide of the present disclosure can be obtained. The time for the secondary firing step can be appropriately changed depending on the temperature, pressure, etc. of the secondary firing step, but is preferably 24 hours or less, and may be 14 hours or less. The time for the secondary firing step may be, for example, 5 minutes or more, 1 hour or more, or 6 hours or more.

[0032] The method for cooling the sintered body of the ion-conductive solid containing the oxide of the present disclosure obtained by the secondary firing step is not particularly limited, and the cooling may be performed naturally (cooling in a furnace), rapidly, or more gradually than naturally, or may be maintained at a certain temperature during cooling.

[0033] Next, the all-solid-state battery of the present disclosure will be described. An all-solid-state battery generally includes a positive electrode, a negative electrode, an electrolyte containing an ion-conducting solid disposed between the positive electrode and the negative electrode, and optionally a current collector.

[0034] The all-solid-state battery of the present disclosure comprises: A positive electrode and a negative electrode; Electrolytes, An all-solid-state battery having at least At least one selected from the group consisting of the positive electrode, the negative electrode, and the electrolyte comprises the ion-conducting solid of the present disclosure.

[0035] The all-solid-state battery of the present disclosure may be a bulk battery or a thin-film battery. The specific shape of the all-solid-state battery of the present disclosure is not particularly limited, but examples thereof include a coin type, a button type, a sheet type, and a laminate type.

[0036] The all-solid-state battery of the present disclosure includes an electrolyte. In the all-solid-state battery of the present disclosure, it is preferable that at least the electrolyte contains the ion-conducting solid of the present disclosure. The solid electrolyte in the all-solid-state battery of the present disclosure may be made of the ion-conductive solid of the present disclosure, or may contain other ion-conductive solids, such as ionic liquids or gel polymers. The other ion-conductive solids are not particularly limited and may be ion-conductive solids commonly used in all-solid-state batteries, such as LiI, Li3PO4, and Li7La3Zr2O. 12The content of the ion-conductive solid of the present disclosure in the electrolyte of the all-solid-state battery of the present disclosure is not particularly limited, and is preferably 25 mass % or more, more preferably 50 mass % or more, even more preferably 75 mass % or more, and particularly preferably 100 mass %.

[0037] The all-solid-state battery of the present disclosure has a positive electrode. The positive electrode may contain a positive electrode active material, or may contain the positive electrode active material and the ion-conducting solid of the present disclosure. As the positive electrode active material, known positive electrode active materials such as sulfides containing transition metal elements and oxides containing lithium and transition metal elements can be used without any particular limitation. For example, LiNiVO4, LiCoPO4, LiCoVO4, LiMn 1.6 Ni 0.4 O4, LiMn2O4, LiCoO2, Fe2(SO4)3, LiFePO4, LiNi 1 / 3 Mn 1 / 3 Co 1 / 3 O2, LiNi 1 / 2 Mn 1 / 2 O2, LiNiO2, Li 1+x (Fe, Mn, Co) 1-x O2, LiNi 0.8 Co 0.15 Al 0.05 Examples include O2. Furthermore, the positive electrode may contain a binder, a conductive agent, etc. Examples of the binder include polyvinylidene fluoride, polytetrafluoroethylene, polyvinyl alcohol, etc. Examples of the conductive agent include natural graphite, artificial graphite, acetylene black, ethylene black, etc.

[0038] The all-solid-state battery of the present disclosure has a negative electrode. The negative electrode may contain a negative electrode active material, or may contain the negative electrode active material and the ion-conductive solid of the present disclosure. As the negative electrode active material, known negative electrode active materials such as inorganic compounds such as lithium, lithium alloys, and tin compounds, carbonaceous materials capable of absorbing and releasing lithium ions, and conductive polymers can be used without particular limitation. For example, Li4Ti5O 12 Examples include: Furthermore, the negative electrode may contain a binder, a conductive agent, etc. As the binder and the conductive agent, the same materials as those exemplified for the positive electrode can be used.

[0039] Here, the expression "including" an electrode active material means that the electrode has the electrode active material as a component, element, or property. For example, the above-mentioned "including" applies to both cases where the electrode contains the electrode active material within the electrode and cases where the electrode active material is applied to the surface of the electrode.

[0040] The positive electrode and the negative electrode can be obtained by known methods such as mixing raw materials, molding, and heat treatment. It is believed that this allows the ion-conductive solid to penetrate into gaps between the electrode active materials, making it easier to secure a conduction path for lithium ions. The ion-conductive solid of the present disclosure can be produced by heat treatment at a lower temperature than conventional techniques, which is believed to suppress the formation of a high-resistance phase that occurs when the ion-conductive solid reacts with the electrode active material.

[0041] The positive electrode and the negative electrode may each have a current collector. Known current collectors such as aluminum, titanium, stainless steel, nickel, iron, baked carbon, conductive polymers, and conductive glass can be used as the current collector. In addition, for the purpose of improving adhesion, conductivity, oxidation resistance, etc., aluminum, copper, or the like whose surface is treated with carbon, nickel, titanium, silver, or the like can be used as the current collector.

[0042] The all-solid-state battery of the present disclosure can be obtained by a known method, for example, by stacking a positive electrode, a solid electrolyte, and a negative electrode, molding, heat treatment, etc. The ion-conductive solid of the present disclosure can be produced by heat treatment at a lower temperature than conventional techniques, which is thought to suppress the formation of a high-resistance phase that occurs when the ion-conductive solid reacts with the electrode active material, and is thought to enable the production of an all-solid-state battery with excellent output characteristics.

[0043] Next, the composition according to the present disclosure and the method for measuring each physical property will be described. -Methods for identifying and analyzing contained metals The composition of the ion-conductive solid is analyzed by wavelength-dispersive X-ray fluorescence spectroscopy (hereinafter referred to as XRF) using a sample solidified by pressure molding. However, if analysis is difficult due to particle size effects, the ion-conductive solid can be vitrified by the glass bead method and then analyzed by XRF. Furthermore, if the yttrium peak and the peaks of the contained metals overlap in XRF, the composition can be analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES). For XRF, the analytical equipment used is the ZSX Primus II manufactured by Rigaku Corporation. The analytical conditions are as follows: Rh is used for the anode of the X-ray tube, vacuum atmosphere, analysis diameter is 10 mm, analysis range is 17° to 81°, step is 0.01°, and scan speed is 5 sec / step. In addition, detection is performed using a proportional counter when measuring light elements, and a scintillation counter when measuring heavy elements. The elements are identified based on the peak positions of the spectrum obtained by XRF, and the molar concentration ratio is calculated from the counting rate (unit: cps), which is the number of X-ray photons per unit time, to determine a, b, c, and d. [Example]

[0044] Examples in which the ion-conductive solid of the present disclosure was specifically produced and evaluated will be described below as examples, although the present disclosure is not limited to the following examples.

[0045] [Example 1] · Primary firing process Li3BO3 (Toshima Manufacturing, purity 99.9% by mass), H3BO3 (Kanto Chemical, purity 99.5%), YO3 (Shin-Etsu Chemical, purity 99.9% by mass), and Yb2O3 (Shin-Etsu Chemical, purity 99.9% by mass) were used as raw materials. Each raw material was weighed in stoichiometric amounts so that b was the value listed in Table 1, and mixed for 30 minutes in a Fritsch planetary mill P-7 at a disk rotation speed of 300 rpm. The planetary mill used zirconia φ5 mm balls and a 45 mL container. After mixing, the mixed powder was cold uniaxially molded at 147 MPa using a 100 kN electric press P3052-10 manufactured by NPA Systems, and then sintered in air at a heating temperature of 650°C for a holding time of 720 minutes. The obtained ion-conductive solid containing oxide was pulverized for 180 minutes at a disk rotation speed of 230 rpm in a planetary mill P-7 manufactured by Fritsch Corporation to prepare a powder of the ion-conductive solid containing oxide. Secondary firing process The powder of the ion-conductive solid containing the oxide obtained above was molded and subjected to secondary firing to produce a sintered body of the ion-conductive solid containing the oxide of Example 1. For molding, the powder was cold uniaxially molded at 147 MPa using a 100 kN electric press P3052-10 manufactured by NPA Systems. Secondary firing was carried out in an air atmosphere at a heating temperature of 650°C for a holding time of 720 minutes.

[0046] [Example 2] A sintered body of an ion-conductive solid containing the oxide of Example 2 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), and HfO2 (manufactured by New Metals, purity 99.9%) as raw materials, and each raw material was weighed out in stoichiometric amounts so that b and c had the values ​​shown in Table 1.

[0047] [Example 3] A sintered body of an ion-conductive solid containing the oxide of Example 3 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), SnO2 (manufactured by Mitsuwa Chemical Co., Ltd., purity 99.9%), and HfO2 (manufactured by New Metals Co., Ltd., purity 99.9%) as raw materials, and each raw material was weighed out in stoichiometric amounts so that b and c were the values ​​shown in Table 1.

[0048] [Example 4] A sintered body of an ion-conductive solid containing the oxide of Example 4 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), In2O3 (manufactured by Shinko Chemical Industry Co., Ltd., purity 99% by mass), HfO2 (manufactured by New Metals, purity 99.9%), and Nb2O5 (manufactured by Mitsui Mining and Smelting, purity 99.9%) as raw materials, and each raw material was weighed out in stoichiometric amounts so that b, c, and d were the values ​​shown in Table 1.

[0049] [Example 5] A sintered body of an ion-conductive solid containing the oxide of Example 5 was produced in the same process as Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b and c were the values ​​shown in Table 1.

[0050] [Example 6] A sintered body of an ion-conductive solid containing the oxide of Example 6 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), In2O3 (manufactured by Shinko Chemical Industry Co., Ltd., purity 99% by mass), and CaO (manufactured by Kanto Chemical, purity 99.0% by mass) were used as raw materials, and each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0051] [Example 7] A sintered body of an ion-conductive solid containing the oxide of Example 7 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Fe2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity 95.0% by mass), and TiO2 (manufactured by Toho Titanium, purity 99%) as raw materials, and each raw material was weighed out in stoichiometric amounts so that b and c were the values ​​shown in Table 1.

[0052] [Example 8] A sintered body of an ion-conductive solid containing the oxide of Example 8 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b and c would have the values ​​shown in Table 1.

[0053] [Example 9] A sintered body of an ion-conductive solid containing the oxide of Example 9 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Lu2O3 (manufactured by Kojundo Chemical Laboratory, purity 99.9% by mass), MgO (manufactured by Ube Material Industries, Ltd., purity 99.0% by mass), and CaO (manufactured by Kanto Chemical, purity 97.0% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0054] [Example 10] A sintered body of an ion-conductive solid containing the oxide of Example 10 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that a, b, and c were the values ​​shown in Table 1.

[0055] [Example 11] A sintered body of an ion-conductive solid containing the oxide of Example 11 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that a, b, and d would have the values ​​shown in Table 1.

[0056] [Example 12] A sintered body of an ion-conductive solid containing the oxide of Example 12 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), La2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.9% by mass), MgO (manufactured by Ube Material Industries, Ltd., purity 99.0% by mass), and CaO (manufactured by Kanto Chemical, purity 97.0% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0057] [Example 13] A sintered body of an ion-conductive solid containing the oxide of Example 13 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), La2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.9% by mass), and MnO (manufactured by Kanto Chemical, purity 80.0% by mass) as raw materials, and that each raw material used in the above examples was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0058] [Example 14] A sintered body of an ion-conductive solid containing the oxide of Example 14 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Tb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), and MnO (manufactured by Kanto Chemical, purity 80.0% by mass) as raw materials, using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0059] [Example 15] A sintered body of an ion-conductive solid containing the oxide of Example 15 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Tm2O3 (manufactured by Kojundo Chemical Laboratory, purity 99.9% by mass), and CaO (manufactured by Kanto Chemical, purity 97.0% by mass) as raw materials, using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0060] [Example 16] A sintered body of an ion-conductive solid containing the oxide of Example 16 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Tm2O3 (manufactured by Kojundo Chemical Laboratory, purity 99.9% by mass), SnO2 (manufactured by Mitsuwa Chemical, purity 99.9%), and Ta2O5 (manufactured by Kanto Chemical, purity 99% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that b, c, and d were the values ​​shown in Table 1.

[0061] [Example 17] A sintered body of an ion-conductive solid containing the oxide of Example 17 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), In2O3 (manufactured by Shinko Chemical Industry Co., Ltd., purity 99% by mass), Nb2O5 (manufactured by Mitsui Mining and Smelting Co., Ltd., purity 99.9%), and Ta2O5 (manufactured by Kanto Chemical, purity 99% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that b and d would have the values ​​shown in Table 1.

[0062] [Example 18] A sintered body of an ion-conductive solid containing the oxide of Example 18 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Pr2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), and ZnO (manufactured by Wako Pure Chemical Industries, Ltd., purity 99% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0063] [Example 19] A sintered body of an ion-conductive solid containing the oxide of Example 19 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b and d would have the values ​​shown in Table 1.

[0064] [Example 20] A sintered body of an ion-conductive solid containing the oxide of Example 20 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Sm2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.9% by mass), HfO2 (manufactured by New Metals, purity 99.9%), and Ta2O5 (manufactured by Kanto Chemical, purity 99% by mass) were used as raw materials, and each raw material was weighed out in stoichiometric amounts so that b, c, and d were the values ​​shown in Table 1.

[0065] [Example 21] A sintered body of an ion-conductive solid containing the oxide of Example 21 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Nd2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Sm2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.9% by mass), and ZnO (manufactured by Wako Pure Chemical Industries, Ltd., purity 99% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 1.

[0066] [Example 22] A sintered body of an ion-conductive solid containing the oxide of Example 22 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Nd2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), and NiO (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.0% by mass) as raw materials, and each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 2.

[0067] [Example 23] A sintered body of an ion-conductive solid containing the oxide of Example 23 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Eu2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 95% by mass), SnO2 (manufactured by Mitsuwa Chemicals, purity 99.9%), and Ta2O5 (manufactured by Kanto Chemical, purity 99% by mass) were used as raw materials, and each raw material was weighed out in stoichiometric amounts so that b, c, and d were the values ​​shown in Table 2.

[0068] [Example 24] A sintered body of an ion-conductive solid containing the oxide of Example 24 was produced using the same process as in Example 1, except that each raw material used in the above example was weighed out in stoichiometric amounts so that a and b were the values ​​shown in Table 2.

[0069] [Example 25] A sintered body of an ion-conductive solid containing the oxide of Example 25 was produced using the same process as in Example 1, except that each raw material used in the above example was weighed out in stoichiometric amounts so that b and c would have the values ​​shown in Table 2.

[0070] [Example 26] A sintered body of an ion-conductive solid containing the oxide of Example 26 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Gd2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Dy2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 95% by mass), and CaO (manufactured by Kanto Chemical, purity 99.0% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 2.

[0071] [Example 27] A sintered body of an ion-conductive solid containing the oxide of Example 27 was produced using the same process as in Example 1, except that each raw material used in the above example was weighed out in stoichiometric amounts so that a, b, and c were the values ​​shown in Table 2.

[0072] [Example 28] A sintered body of an ion-conductive solid containing the oxide of Example 28 was produced using the same process as in Example 1, except that each raw material used in the above example was weighed out in stoichiometric amounts so that b and c would have the values ​​shown in Table 2.

[0073] [Example 29] A sintered body of an ion-conductive solid containing the oxide of Example 29 was produced using the same process as in Example 1, except that each raw material used in the above example was weighed out in stoichiometric amounts so that b and d would have the values ​​shown in Table 2.

[0074] [Example 30] A sintered body of an ion-conductive solid containing the oxide of Example 30 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Tb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), NiO (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.0% by mass), and BaO (manufactured by Wako Pure Chemical Industries, Ltd., purity 90.0% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 2.

[0075] [Example 31] A sintered body of an ion-conductive solid containing the oxide of Example 31 was produced using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Tb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Ho2O3 (manufactured by Kojundo Chemical Laboratory, purity 99.9% by mass), and BaO (manufactured by Wako Pure Chemical Industries, Ltd., purity 90.0% by mass) as raw materials using the same process as in Example 1, except that each raw material was weighed out in stoichiometric amounts so that a and b had the values ​​shown in Table 2.

[0076] [Example 32] A sintered body of an ion-conductive solid containing the oxide of Example 32 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that a and b were the values ​​shown in Table 2, and the disk rotation speed during grinding was set to 300 rpm.

[0077] [Example 33] A sintered body of an ion-conductive solid containing the oxide of Example 33 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b, c, and d would have the values ​​shown in Table 2.

[0078] [Example 34] A sintered body of an ion-conductive solid containing the oxide of Example 34 was produced using the same process as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), H3BO3 (manufactured by Kanto Chemical, purity 99.5%), YO3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass), Er2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity 95% by mass), Tm2O3 (manufactured by Kojundo Chemical Laboratory, purity 99.9% by mass), and SrO (manufactured by Kojundo Chemical Laboratory, purity 98% by mass) as raw materials, and that each raw material was weighed out in stoichiometric amounts so that a and b were the values ​​shown in Table 2.

[0079] [Example 35] A sintered body of an ion-conductive solid containing the oxide of Example 35 was produced in the same manner as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b and c were the values ​​shown in Table 2.

[0080] [Example 36] A sintered body of an ion-conductive solid containing the oxide of Example 36 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that a, b, and c were the values ​​shown in Table 2.

[0081] [Example 37] A sintered body of an ion-conductive solid containing the oxide of Example 37 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b and d would have the values ​​shown in Table 2.

[0082] [Example 38] A sintered body of an ion-conductive solid containing the oxide of Example 38 was produced using the same process as in Example 1, except that each raw material used in the above example was weighed out in stoichiometric amounts so that b and d would have the values ​​shown in Table 2.

[0083] [Example 39] A sintered body of an ion-conductive solid containing the oxide of Example 39 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that a and b would have the values ​​shown in Table 2.

[0084] [Example 40] A sintered body of an ion-conductive solid containing the oxide of Example 40 was produced by the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b and d would have the values ​​shown in Table 2.

[0085] [Example 41] A sintered body of an ion-conductive solid containing the oxide of Example 41 was produced using the same process as in Example 1, except that each raw material used in the above examples was weighed out in stoichiometric amounts so that b and d would have the values ​​shown in Table 2.

[0086] [Comparative Example 1] A sintered body of an ion-conductive solid containing oxide was produced using the same process as in Example 1, except that LiBO (manufactured by Toshima Manufacturing Co., Ltd., purity 99.9% by mass), HBO (manufactured by Kanto Chemical, purity 99.5%), and YO (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.9% by mass) were used as raw materials.

[0087] The composition analysis was carried out by the above method for the sintered bodies of the ion-conductive solids containing oxides of Examples 1 to 41. In addition, the volume average particle size of the powders of the ion-conductive solids obtained in Examples 1 to 41 and Comparative Example 1 and the ionic conductivity of the sintered bodies of the ion-conductive solids were measured by the following method. The methods for measuring the ionic conductivity and the volume average particle size are described below, and the evaluation results are shown in Tables 1 and 2.

[0088] -Ionic conductivity measurement The two large, parallel faces of the sintered plate-shaped oxide-containing ion-conductive solid obtained by the secondary firing were polished with sandpaper. The dimensions of the sintered plate-shaped oxide-containing ion-conductive solid were, for example, 0.9 cm × 0.9 cm × 0.05 cm, but are not limited to this. Polishing was first performed with #500 for 15 to 30 minutes, then with #1000 for 10 to 20 minutes, and finally with #2000 for 5 to 10 minutes. The polished surface was considered complete when there were no visible irregularities or scratches. After polishing, a gold film was formed on the polished surface of the sintered body of ion-conductive solid containing oxide using a Sanyu Electronics sputtering device SC-701MkII ADVANCE. The film formation conditions were Ar process gas, vacuum level 2 Pa to 5 Pa, and film formation time 5 minutes, and the measurement sample was used. After film formation, the AC impedance of the measurement sample was measured. For the impedance measurement, an impedance / gain phase analyzer SI1260 and a dielectric interface system 1296 (both manufactured by Solartron) were used, and the measurement conditions were a temperature of 27°C, an amplitude of 20 mV, and a frequency of 0.1 Hz to 1 MHz. The resistance of the sintered body of ion-conductive solid containing oxide was calculated using the Nyquist plot obtained from the impedance measurement and Scribner's AC analysis software ZVIEW. An equivalent circuit corresponding to the measurement sample was set up in ZVIEW, and the resistance of the sintered body of ion-conductive solid containing oxide was calculated by fitting and analyzing the equivalent circuit and Nyquist plot. The ionic conductivity was calculated using the calculated resistance, the thickness of the sintered body of ion-conductive solid containing oxide, and the electrode area using the following formula. Ionic conductivity (S / cm) = Thickness of sintered ion-conductive solid containing oxide (cm) / (Resistance of sintered ion-conductive solid containing oxide (Ω) × Electrode area (cm 2 ))

[0089] The ionic conductivity (S / cm) of the sintered body of the ion-conductive solid is preferably 1.00×10 -9 More preferably, it is 1.00×10 -8 or more, and more preferably 1.00×10 -7or more, and even more preferably 1.00×10 -6 More preferably, it is 1.00×10 -5 The higher the conductivity, the better. There is no particular upper limit to the conductivity. For example, 1.00×10 -2 Below, 1.00 x 10 -3 Below, 1.00 x 10 -4 The following is the result.

[0090] -Evaluation of volume average particle size The ion-conductive solid powder containing oxides obtained by ball milling (Fritsch Planetary Mill P-7) after primary firing was subjected to particle size distribution measurement using a Horiba LA-960V2 laser diffraction / scattering particle size distribution analyzer. The refractive index was set to 1.8, and ethanol was used as the measurement solvent. The sample concentration was adjusted so that the transmittance was 90-70%. The volume-average particle size was calculated from the obtained frequency distribution.

[0091] ·result Tables 1 and 2 show the stoichiometric amounts (general formula Li) of raw materials used in producing sintered bodies of ion-conductive solids containing each oxide in Examples 1 to 41 and Comparative Example 1. 6+a-c-2d Y 1-a-b-c-d M1 a M2 b M3 c M4 d The values ​​of a, b, c, and d in B3O9), volume average particle size, and ionic conductivity are summarized. As a result of the composition analysis, it was confirmed that the sintered bodies of ion-conductive solids containing oxides of Examples 1 to 41 and Comparative Example 1 all had compositions in accordance with the stoichiometric amounts of the raw materials listed in Tables 1 and 2. Furthermore, the sintered bodies of ion-conductive solids containing oxides of Examples 1 to 41 were ion-conductive solids that exhibited high ionic conductivity even when fired at temperatures below 700°C.

[0092] [Table 1] [Table 2]

[0093] As shown in Table 2, the ion conductivity of the ion-conductive solid produced in Example 31 was improved compared to Example 32. Because the composition and substitution elements differ from those disclosed in the prior art, differences in melting point and the like may affect the density after firing, which may result in a difference in the appropriate range of particle size.

Claims

1. General formula Li ６＋ａ－ｃ－２ｄ Y １－ａ－ｂ－ｃ－ｄ M1 ａ M2 ｂ M3 ｃ M4 ｄ B ３ O ９ An ionically conductive solid comprising an oxide represented by the formula: (In the formula, M1 is at least one metal element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr, and Ba, M2 is at least one metal element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, In, and Fe; M3 is at least one metal element selected from the group consisting of Hf, Sn, and Ti, M4 is at least one metal element selected from the group consisting of Nb and Ta, a is a real number that satisfies 0.000≦a≦0.800, b is a real number that satisfies 0.300≦b≦0.900, c is a real number that satisfies 0.000≦c≦0.800, d is a real number that satisfies 0.000≦d≦0.800, and a, b, c, and d are real numbers that satisfy 0.300≦a+b+c+d<1.000 and 0.100≦1-a-b-c-d.

2. 2. The ion-conducting solid according to claim 1, wherein 1-abcd satisfies 0.300≦1-abcd.

3. 2. The ion-conducting solid according to claim 1, wherein 1-abcd satisfies 0.500≦1-abcd.

4. 2. The ion-conducting solid according to claim 1, wherein a satisfies the condition 0.000≦a≦0.

400.

5. 2. The ion-conducting solid according to claim 1, wherein c satisfies the condition 0.000≦c≦0.

400.

6. 2. The ion-conducting solid according to claim 1, wherein d satisfies the condition 0.000≦d≦0.

400.

7. 2. The ion-conductive solid according to claim 1, wherein the volume average particle size is 0.1 μm or more and 28.0 μm or less.

8. A positive electrode and a negative electrode; Electrolytes, An all-solid-state battery having at least An all-solid-state battery, wherein at least one selected from the group consisting of the positive electrode, the negative electrode, and the electrolyte comprises the ion-conducting solid according to any one of claims 1 to 7.

9. The all-solid-state battery according to claim 8 , wherein at least the electrolyte comprises the ion-conducting solid.

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