ION-CONDUCTIVE SOLID AND SOLID BATTERY

Abstract

An ionically conductive solid that can be produced by low-temperature heat treatment and exhibits high ionic conductivity; and the ionically conductive solid has an oxide represented by a general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 d B3O9 (In the formula, M1 is at least one metallic element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr and Ba, M2 is at least one metallic element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, In, and Fe, M3 is at least one metallic element selected from the group consisting of Zr, Ce, Hf, Sn and Ti, M4 is at least one metallic element selected from the group consisting of Nb and Ta, and a, b, c and d are real numbers, each of which lies in a certain range and satisfies 0.000 ≤ a + b + c + d < 1.000).

Description

[Technical field]

[0001] The present disclosure relates to an ion-conducting solid and a solid-state battery. [State of the art]

[0002] Conventionally, lightweight, high-capacity lithium-ion secondary batteries were included in mobile devices such as smartphones and notebooks, as well as in transport devices such as electric vehicles and hybrid electric vehicles.

[0003] However, since conventional lithium-ion secondary batteries used liquids containing flammable solvents as electrolytes, there were concerns about leakage of these solvents and ignition in the event of a battery short circuit. Therefore, in recent years, secondary batteries using ionically conductive solids as electrolytes, which differ from liquid electrolytes, have been considered to ensure safety, and such secondary batteries are known as solid-state batteries.

[0004] Solid electrolytes, such as oxide-based and sulfide-based solid electrolytes, are widely used in solid-state batteries. Among them, oxide-based solid electrolytes do not react with atmospheric moisture and do not produce hydrogen sulfide; therefore, they are safer than sulfide-based solid electrolytes.

[0005] Furthermore, a solid-state battery comprises: a cathode containing a cathode active material; an anode containing an anode active material; an electrolyte containing an ionically conductive solid positioned between the cathode and the anode; and, if required, a current collector (the cathode active material and the anode active material are collectively referred to as the "electrode active material"). When manufacturing a solid-state battery using an oxide-based solid electrolyte, a heat treatment is performed to reduce the contact resistance between the particles of the oxide-based material contained in the solid electrolyte. However, with a conventional oxide-based material, a high temperature of 900°C or more is required for the heat treatment, and the solid electrolyte and the electrode active material can therefore react to form a high-resistance phase.The high-resistance phase can lead to a decrease in the ionic conductivity of the ionically conductive solid and thus to a decrease in the performance of the solid-state battery.

[0006] Examples of oxide-based solid electrolytes that can be produced by heat treatment at a temperature of less than 900°C include Li 2+x C 1-x B x O3 (Non-patent literature 1).

[0007] Furthermore, it is revealed that the properties can be improved by using the Li described above. 2+x C 1-x B x O3 may contain a specific element in a specific ratio (Patent Literature 1). [Citation list][Non-patent literature]

[0008] [NPL1] Solid State Ionic 288 (2016) 248-252 [Patent literature]

[0009] [PTL1] Japanese Patent No. 6948676 [Brief description of the invention][Technical problem]

[0010] The present disclosure provides: an ionically conductive solid that can be produced by low-temperature heat treatment and exhibits high ionic conductivity; and a solid-state battery comprising the ionically conductive solid. [Solution to the problem]

[0011] An ionically conductive solid of the present disclosure is an ionically conductive solid comprising an oxide represented by a general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 d B3O9 (in the formula, M1 is at least one metallic element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr and Ba, M2 is at least one metallic element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, In and Fe, M3 is at least one metallic element selected from the group consisting of Zr, Ce, Hf, Sn and Ti, M4 is at least one metallic element selected from the group consisting of Nb and Ta, and a is 0.000 ≤ a ≤ 0.800, b is 0.000 ≤ 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 0.000 ≤ a + b + c + d < 1.000).

[0012] A solid-state battery in the present disclosure is a solid-state battery that has at least the following: a cathode; an anode; and an electrolyte, wherein at least one selected from the group consisting of the cathode, the anode and the electrolyte comprises the ionically conductive solid of the present disclosure. [Advantageous effects of the invention]

[0013] From one perspective of the present disclosure, the following can be obtained: an ionically conductive solid which can be produced by heating at a low temperature and which has a high ionic conductivity; and a solid-state battery which comprises the ionically conductive solid. [Description of the embodiments]

[0014] In the present disclosure, the description “XX or more and YY or less” or “XX to YY”, which represents a numerical range, means a numerical range that includes lower and upper limits, which are the endpoints unless otherwise specified. When numerical ranges are described step by step, the upper and lower limits of each numerical range may optionally be combined.

[0015] In the present disclosure, the term “solid” refers to the state of matter with a certain shape and volume in the three states of matter, and a powdery state is included in “solid”.

[0016] An ionically conductive solid of the present disclosure is an ionically conductive solid comprising an oxide represented by a general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 d B3O9. In the formula, M1 is at least one metallic element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr and Ba, M2 is at least one metallic element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, In and Fe, M3 is at least one metallic element selected from the group consisting of Zr, Ce, Hf, Sn and Ti, M4 at least one metallic element selected from the group consisting of Nb and Ta, and a is 0.000 ≤ a ≤ 0.800, b is 0.000 ≤ 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 0.000 ≤ a + b + c + d < 1.000.

[0017] The present inventors propose the following as the reason why the ionically conductive solid, which contains the oxide represented by the general formula described above, exhibits improved ionic conductivity.

[0018] The substitution of Y in Li6YB3O9 by Yb with a small ionic radius, as described in comparative example 1 in Japanese patent no. 6948676, leads to a reduction in the lattice constant and the lattice volume, and facilitates the movement of Li + and therefore improves ion conductivity.

[0019] Furthermore, Japanese patent no. 6948676 describes how substituting some trivalent Y elements with tetravalent or pentavalent elements establishes charge balance by substituting elements with different valencies, thus improving ionic conductivity. Using Yb instead of Yb reduces the lattice constant and lattice volume, facilitating the movement of Li. + further and therefore causes a further improvement in ion conductivity.

[0020] The ionically conductive solid of the present disclosure preferably has a monoclinic crystal structure.

[0021] The ionically conductive solid of the present disclosure preferably has a volume-averaged particle diameter of 0.1 µm or more and 28.0 µm or less, more preferably 0.2 µm or more and 26.0 µm or less, even more preferably 0.3 µm or more and 20.0 µm or less, even more preferably 0.3 µm or more and 15.0 µm or less, and even more preferably 0.5 µm or more and 10.0 µm or less. The range described above leads to a reduction in the grain boundary resistance in an ionically conductive solid and to a further improvement in the ionic conductivity.

[0022] The volume-averaged particle diameter of the ion-conducting solid can be controlled by pulverization or classification.

[0023] In the general formula described above, a is a real number that satisfies 0.000 ≤ a ≤ 0.800.

[0024] The value of 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 preferred 0.000 ≤ a ≤ 0.050, and most preferred 0.000 ≤ a ≤ 0.030.

[0025] In the general formula described above, b is a real number that satisfies 0.000 ≤ b ≤ 0.900.

[0026] The b is 0.000 ≤ b ≤ 0.900, preferably 0.000 ≤ b ≤ 0.600, more preferred 0.000 ≤ b ≤ 0.500, even more preferred 0.000 ≤ b ≤ 0.400, still more preferred 0.000 ≤ b ≤ 0.100, particularly preferred 0.000 ≤ b ≤ 0.050, and most preferred 0.000 ≤ b ≤ 0.030.

[0027] In the general formula described above, c is a real number that satisfies 0.000 ≤ c ≤ 0.800.

[0028] The value of 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 ≤ 0.150, still more preferably 0.000 ≤ c ≤ 0.100, particularly preferably 0.000 ≤ c ≤ 0.050, and most preferably 0.000 ≤ c ≤ 0.030. Furthermore, c can preferably be 0.050 ≤ c ≤ 0.200 and more preferably 0.080 ≤ c ≤ 0.150.

[0029] In the general formula described above, d is a real number that satisfies 0.000 ≤ d ≤ 0.800.

[0030] The 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 most preferably 0.010 ≤ d ≤ 0.030.

[0031] In the general formula described above, a + b + c + d is a real number that satisfies 0.000 ≤ a + b + c + d < 1.000.

[0032] The a + b + c + d is 0.000 ≤ a + b + c + d < 1.000, preferably 0.000 ≤ a + b + c + d < 0.900, more preferred 0.000 ≤ a + b + c + d < 0.800, even more preferred 0.000 ≤ a + b + c + d < 0.700, even more preferred 0.000 ≤ a + b + c + d ≤ 0.600, particularly preferred 0.010 ≤ a + b + c + d < 0.500, particularly preferred 0.050 ≤ a + b + c + d < 0.300, and most preferred 0.080 ≤ a + b + c + d < 0.250.

[0033] At Yb 1-a-b-c-d 1-abcd is preferably 0.300 ≤ 1-abcd, more preferably 0.500 ≤ 1-abcd, even more preferably 0.700 ≤ 1-abcd, and still more preferably 0.750 ≤ 1-abcd. The upper limit is not particularly restricted, but is preferably less than 1.000, 0.950 or less, and 0.900 or less.

[0034] The ionically conductive solid of the present disclosure may, for example, have the following embodiments, but is not limited to these. (1) It is sufficient that a satisfies the condition 0.010 ≤ a ≤ 0.100, b satisfies the condition 0.000 ≤ b ≤ 0.200, c satisfies the condition 0.000 ≤ c ≤ 0.200, d satisfies the condition 0.010 ≤ d ≤ 0.100, and a, b, c and d satisfy the condition 0.010 ≤ a + b + c + d < 0.300. (2) It is sufficient that a satisfies the condition 0.010 ≤ a ≤ 0.030, b satisfies the condition 0.030 ≤ b ≤ 0.100, c satisfies the condition 0.010 ≤ c ≤ 0.030, d satisfies the condition 0.010 ≤ d ≤ 0.030 and a, b, c and d satisfy the condition 0.050 ≤ a + b + c + d < 0.160. (3) It is sufficient that a satisfies the condition 0.000 ≤ a ≤ 0.010, b satisfies the condition 0.000 ≤ b ≤ 0.100, c satisfies the condition 0.050 ≤ c ≤ 0.150, d satisfies the condition 0.000 ≤ d ≤ 0.030, and a, b, c and d satisfy the condition 0.050 ≤ a + b + c + d < 0.250. M1, M2, M3, and M4 in the general formula above may or may not be included in the formula. In other words, at least one of a, b, c, and d can be zero.

[0035] In the general formula, as described above, M1 is at least one metallic element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr and Ba.

[0036] 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.

[0037] In the general formula, as described above, M2 is at least one metallic element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, In and Fe.

[0038] M2 is at least one selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, In and Fe, preferably at least one selected from the group consisting of La, Eu, Gd, Tb, Dy, Lu, In and Fe, and more preferably at least one selected from the group consisting of Gd, Dy, Lu, In and Fe.

[0039] In the general formula, as described above, M3 is at least one metallic element selected from the group consisting of Zr, Ce, Hf, Sn and Ti.

[0040] M3 is at least one selected from the group consisting of Zr, Ce, Hf, Sn and Ti, preferably at least one selected from the group consisting of Zr, Ce, Hf and Sn, and more preferably at least one selected from the group consisting of Zr, Ce and Hf.

[0041] In the general formula, as described above, M4 is at least one metallic element selected from the group consisting of Nb and Ta.

[0042] M4 is at least one selected from the group consisting of Nb and Ta, preferably Nb.

[0043] When a proportion of Yb, which are trivalent metal elements, is substituted within a specific ratio by certain elements M1, M2, M3, and M4, the charge equilibrium is adjusted by the substitution between the elements with different valencies. Therefore, a state is reached in which Li + The crystal lattice is deficient. This is because the surrounding Li + this lack of Li + By balancing the ions, the ionic conductivity is improved.

[0044] The following describes a method for producing the ionically conductive solid of the present disclosure.

[0045] The method for producing the ionically conductive solid of the present disclosure may be, but is not limited to, the following point of view.

[0046] Method for producing an ionically conductive solid comprising an oxide represented by a general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 d B3O9, the procedure may include: a primary combustion step of the heat treatment of raw materials which are mixed to obtain the oxide represented by the general formula, at a temperature below the melting point of the oxide. In the formula, M1 is at least one metallic element selected from the group consisting of Mg, Mn, Zn, Ni, Ca, Sr, and Ba; M2 is at least one metallic element selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, In, and Fe; M3 is at least one metallic element selected from the group consisting of Zr, Ce, Hf, Sn, and Ti; M4 is at least one metallic element selected from the group consisting of Nb and Ta; a is 0.000 ≤ a ≤ 0.800; b is 0.000 ≤ 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. 0.000 ≤ a + b + c + d < 1.000 must be satisfied.

[0047] The process for producing the ionically conductive solid of the present disclosure may include the primary firing step in which the raw materials are weighed and mixed to obtain the oxide represented by the general formula described above, the raw materials are heat-treated at a temperature below the melting point of the oxide, and the ionically conductive solid containing the oxide is thereby produced. The ionically conductive solid can be obtained by the primary firing step.

[0048] The process may also include, if necessary, a secondary firing step in which the ionically conductive solid containing the obtained oxide is heat-treated at a temperature below the melting point of the oxide, and a sintered body is produced from the ionically conductive solid containing the oxide.

[0049] The process for producing the ionically conductive solid of the present disclosure, which includes the primary firing step and the secondary firing step described above, is described in detail below, although the present disclosure is not limited to the following manufacturing process. Primary firing step

[0050] In the primary firing step, raw materials such as Li3BO3, H3BO3, Yb2O3, ZrO2, CeO2 or HfO2 of chemical reagent quality are weighed out and mixed in stoichiometric amounts, resulting in the general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 dB3O9 (where M1 is one or more metallic elements selected from Mg, Mn, Zn, Ni, Ca, Sr and Ba, M2 is one or more metallic elements selected from La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, In and Fe, M3 is one or more metallic elements selected from Zr, Ce, Hf, Sn and Ti, M4 is one or more metallic elements selected from Nb and Ta, a is 0.000 ≤ a ≤ 0.800, b is 0.000 ≤ 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 0.000 ≤ a + b + c + d < 1.000 are satisfied).

[0051] The equipment used for mixing is not particularly limited. For example, a pulverizing-type mixer such as a planetary ball mill can be used. The material and capacity of the mixing container, as well as the material and diameter of the ball, are not particularly restricted and can be selected according to the type and quantity of raw materials used. For example, a 45 mL zirconium dioxide container and a 5 mm diameter zirconium dioxide ball can be used. Furthermore, the conditions for the mixing process are not particularly limited; for example, a rotational speed of 50 to 2000 rpm and a time of 10 to 60 minutes can be set.

[0052] After the powder mixture from each of the raw materials described above has been obtained through the mixing process, the resulting powder mixture is press-molded to produce pellets. A known pressure forming process, such as a cold uniaxial forming process or a cold isostatic pressure forming process, can be used. The pressure required for the initial firing step is not particularly limited, but can, for example, be set to a pressure of 100 MPa to 200 MPa.

[0053] The resulting pellets are burned using a device such as an atmospheric burner. The temperature at which the primary combustion and solid-phase synthesis are carried out is not particularly limited, as long as the temperature remains below the melting point of the ionically conductive solid, which is represented by the general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 cM4 d B3O9. The temperature at which the primary firing is performed can be set, for example, to less than 700°C, 680°C or less, 670°C or less, 660°C or less, or 650°C or less, and, for example, to 500°C or more. The numerical ranges can optionally be combined. The temperature within such a range, as described above, enables sufficient solid-phase synthesis. The duration of the primary firing step is not particularly limited, but can, for example, be set to approximately 700 to 750 minutes.

[0054] The primary firing step described above enables the production of the ionically conductive solid, which contains the oxide represented by the general formula described above: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 dB3O9. The powder of the ionically conductive solid containing the oxide can also be obtained by pulverizing the ionically conductive solid containing the oxide using a mortar / punch or a planetary mill. Secondary firing step

[0055] In the secondary firing step, at least one product selected from the group consisting of the ionically conductive solid containing the oxide obtained in the primary firing step and the powder of the ionically conductive solid containing the oxide, is pressure-formed and sintered as required to obtain the sintered body of the ionically conductive solid containing the oxide. It is acceptable to perform the pressure forming and secondary firing simultaneously using discharge plasma sintering (hereinafter referred to simply as "SPS"), hot pressing, or the like, or it is acceptable to produce pellets by cold uniaxial forming and then perform the secondary firing in an ambient, oxidizing, reducing, or the like atmosphere.The conditions described above make it possible to obtain an ionically conductive solid with high ionic conductivity without causing melting through heat treatment. The conditions for pressure forming in the secondary firing step are not particularly limited; for example, they can be set to a pressure of 10 MPa to 100 MPa.

[0056] The temperature at which secondary firing is carried out is lower than the melting point of the ionically conductive solid, which is represented by the general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 dB3O9. The temperature at which the post-firing is carried out 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 restricted, but it is preferred to reduce the lower limit as much as possible, for example, to 500°C or more. The temperature ranges can optionally be combined and set within a range of, for example, 500°C or more and less than 700°C. The range described above enables the ionically conductive solid, which comprises the oxide of the present disclosure, to be prevented from melting or decomposing in the secondary firing step, and ensures that the sintered body of the ionically conductive solid, which comprises the oxide of the present disclosure, is obtained in a sufficiently sintered state.

[0057] The duration of the secondary firing step can be varied depending on the temperature or pressure at which the secondary firing step is performed, and is preferably 24 hours or less, and can be set to 14 hours or less. The duration of the secondary firing step can be set, for example, to 5 minutes or more, 1 hour or more, and 6 hours or more.

[0058] A method for cooling the sintered body of the ionically conductive solid, which has the oxide of the present disclosure obtained in the secondary firing stage, is not particularly limited, but may be subjected to natural radiative cooling (radiative cooling in a furnace), rapid cooling or slower cooling than natural radiative cooling, or it may be kept at a certain temperature during cooling.

[0059] A solid-state battery in the present disclosure will now be described.

[0060] A solid-state battery typically includes: a cathode, an anode, an electrolyte located between the cathode and anode and comprising an ionically conductive solid, and optionally a current collector.

[0061] The solid-state battery of the present disclosure has at least the following features: a cathode; an anode; and an electrolyte, wherein at least one selected from the group consisting of the cathode, the anode and the electrolyte comprises the ionically conductive solid of the present disclosure.

[0062] The solid-state battery of the present disclosure can be a bulk-type battery or a thin-film battery. The specific shape of the solid-state battery of the present disclosure is not particularly limited, but examples include the shape of a coin, the shape of a button, the shape of a sheet, and layered forms.

[0063] The solid-state battery of the present disclosure comprises the electrolyte. Furthermore, the solid-state battery of the present disclosure comprises at least the electrolyte, preferably the ionically conductive solid of the present disclosure.

[0064] The solid electrolyte in the solid-state battery of the present disclosure may comprise the ionically conductive solid of the present disclosure, may comprise another ionically conductive solid, or may comprise an ionic liquid or a gel polymer. The other ionically conductive solid is not particularly limited, but may comprise an ionically conductive solid commonly used in a solid-state battery, e.g., LiI, Li3PO4, Li7La3Zr2O 12 , or the like. The content of the ionically conductive solid of the present disclosure in the electrolyte in the solid-state battery of the present disclosure is not particularly limited, but is preferably 25 wt% or more, more preferably 50 wt% or more, even more preferably 75 wt% or more and particularly preferably 100 wt%.

[0065] The solid-state battery of the present disclosure includes the cathode. The cathode may comprise the cathode active material or the cathode active material and the ionically conductive solid of the present disclosure. Any known cathode active material, such as a sulfide containing a transition metal element or an oxide containing lithium and a transition metal element, may be used as the cathode active material without particular restriction. Examples include LiNiVO4, LiCoPO4, LiCoVO4, and 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 and LiNi 0.8 Co 0,15 Al 0,05 O2.

[0066] Furthermore, the cathode may contain a binder, an electrically conductive material, and / or the like. Examples of binders include polyvinylidene fluoride, polytetrafluoroethylene, and polyvinyl alcohol. Examples of electrically conductive materials include natural graphite, synthetic graphite, acetylene black, and ethylene black.

[0067] The solid-state battery of the present disclosure includes the anode. The anode may comprise the anode active material, or it may comprise the anode active material and the ionically conductive solid of the present disclosure. Without particular limitation, the anode active material may be any known anode active material such as an inorganic compound like lithium, a lithium alloy, or a tin compound, a carbon-containing material capable of absorbing and releasing a lithium ion, or a conductive polymer. Examples include Li₄Ti₅O₂. 12 .

[0068] Furthermore, the anode may contain a binder, an electrically conductive material, and / or the like. Similar binders and electrically conductive materials to those used in the cathode may be used as the binder and electrically conductive material.

[0069] When we refer to an electrode that "incorporates" an electrode active material, this means that the electrode has an electrode active material as a component, element, or property. For example, a case where an electrode contains an active material, and a case where an active material is applied to the surface of an electrode, also correspond to the "incorporating" described above.

[0070] The cathode and anode can be produced by a known process such as mixing, shaping, heat treatment, or the like of raw materials. It is assumed that the ionically conductive solid penetrates gaps and the like between such electrode active materials to facilitate the safety of a conduction path for lithium ions. It is further assumed that, since the ionically conductive solid of the present disclosure can be produced by heat treatment at a lower temperature compared to conventional technologies, the formation of a high-resistance phase resulting from a reaction between the ionically conductive solid and the electrode active material can be suppressed.

[0071] The cathode and anode described above can incorporate a current collector. A known current collector such as aluminum, titanium, stainless steel, nickel, iron, calcined carbon, a conductive polymer, or electrically conductive glass can be used. Furthermore, to improve adhesion, electrical conductivity, oxidation resistance, and the like, aluminum, copper, or similar materials whose surface is treated with carbon, nickel, titanium, silver, or the like can be used as the current collector.

[0072] The solid-state battery of the present disclosure can be manufactured according to a known method in which, for example, the cathode, the solid electrolyte, and the anode are layered, shaped, and heat-treated. It is assumed that, since the ionically conductive solid of the present disclosure can be manufactured by heat treatment at a lower temperature compared to conventional technologies, the formation of a high-resistance phase generated by the reaction between the ionically conductive solid and the electrode active material can be suppressed, and that thus the solid-state battery with superior performance characteristics can be obtained.

[0073] The following describes a method for measuring the composition and each physical property according to the present disclosure. -Methods for the identification and analysis of included metals

[0074] The composition of the ionically conductive solid is analyzed by wavelength dispersion X-ray fluorescence analysis (hereinafter referred to as "XRF") using a sample solidified by a compression molding process. However, if the analysis proves difficult due to particle size effects and / or the like, it is preferred to vitrify the ionically conductive solid using a glass bead technique and analyze its composition by XRF. If the peaks of yttrium and the peaks of the included metals overlap in the X-ray fluorescence analysis, the composition is preferably analyzed by inductively coupled plasma spectroscopy (ICP-AES).

[0075] In the case of XRF analysis, the ZSX Primus II instrument manufactured by Rigaku Corporation is used. The analysis conditions are set for the use of rhenium as the anode of an X-ray tube, a vacuum atmosphere, an analysis diameter of 10 mm, an analysis range of 17° to 81°, a step size of 0.01°, and a scan speed of 5 seconds per step. Furthermore, detection of lighter elements is performed using a proportional counter, and detection of heavier elements is performed using a scintillation counter.

[0076] An element is identified based on the peak position of an XRF spectrum, and the molar concentration ratios are calculated based on a count rate (unit: cps), i.e., the number of X-ray photons per unit of time, to determine a, b, c, and d. Examples

[0077] Examples in which the ionically conductive solid of the present disclosure has been specifically manufactured and evaluated are described below as examples. The present disclosure is not limited to the following examples. [Example 1] - Primary Firing Step

[0078] Using Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), and Nb2O5 (manufactured by MITSUI MINING & SMELTING CO., LTD., purity of 99.9%) as raw materials, each raw material was weighed in stoichiometric amounts, such that d was a value set in Table 1, and mixed for 30 minutes in a P-7 planetary mill manufactured by Fritsch GmbH at a disc speed of 300 rpm. A 5 mm diameter zirconium dioxide ball and a 45 mL container were used in the planetary mill.

[0079] After mixing, the powder was cold-formed uniaxially using a 100 kN electric press P3052-10 from NPa SYSTEM Co. at 147 MPa and fired in an ambient atmosphere. The heating temperature was set to 650°C and the residence time to 720 minutes.

[0080] The resulting ionically conductive solid containing the oxide was ground for 180 minutes at a disk speed of 230 rpm in the P-7 planetary mill manufactured by Fritsch GmbH to produce the powder of the ionically conductive solid containing the oxide. -Secondary combustion stage

[0081] The powder of the ionically conductive solid containing the oxide, obtained as described above, was shaped and secondarily fired to produce a sintered body of the ionically conductive solid containing the oxide of Example 1. For shaping, the powder was cold-formed uniaxially at 147 MPa using a 100 kN electric press P3052-10 from NPa SYSTEM Co. Secondary firing was carried out in an ambient atmosphere, with the heating temperature set to 650°C and the residence time to 720 minutes. [Example 2]

[0082] The sintered body of the ionically conductive solid containing the oxide of Example 2 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%) and CeO2 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that c was a value given in Table 1. [Example 3]

[0083] The sintered body of the ionically conductive solid containing the oxide, from Example 3, was produced in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), ZrO2 (manufactured by Nippon Denko Co., Ltd., purity of 99.9%), CeO2 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9%), and Nb2O5 (manufactured by MITSUI MINING & SMELTING CO., LTD., purity of 99.9%) were used as raw materials, each raw material being stoichiometric amounts were weighed out, so that c and d were the values ​​given in Table 1. [Example 4]

[0084] The sintered body of the ionically conductive solid containing the oxide of Example 4 was produced in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts so that the values ​​given in Table 1 were achieved. [Example 5]

[0085] The sintered body of the ionically conductive solid containing the oxide of Example 5 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%) and HfO2 (manufactured by New Metals and Chemicals Corporation, Ltd., purity of 99.9%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that c was a value listed in Table 1. [Example 6]

[0086] The sintered body of the ionically conductive solid containing the oxide of Example 6 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, such that c was a value given in Table 1. [Example 7]

[0087] The sintered body of the ionically conductive solid containing the oxide of Example 7 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that c and d were the values ​​given in Table 1. [Example 8]

[0088] The sintered body of the ionically conductive solid containing the oxide from Example 8 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), In2O3 (manufactured by Shinko Chemical Co., Ltd., purity of 99 wt%), SnO2 (manufactured by Mitsuwa Chemicals Co., Ltd., purity of 99.9 wt%), and CeO2 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts. was so that b and c were the values ​​given in Table 1. [Example 9]

[0089] The sintered body of the ionically conductive solid containing the oxide of Example 9 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that b and c were the values ​​given in Table 1. [Example 10]

[0090] The sintered body of the ionically conductive solid, which has the oxide of Example 10, was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5 wt%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Fe2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity of 95.0 wt%) and TiO2 (manufactured by TOHO TITANIUM CO., LTD., purity of 99%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that b and c were the values ​​given in Table 1. [Example 11]

[0091] The sintered body of the ionically conductive solid containing the oxide of Example 11 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that b and c were the values ​​given in Table 1. [Example 12]

[0092] The sintered body of the ionically conductive solid containing the oxide of Example 12 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%) and Lu2O3 (manufactured by Kojundo Chemical Laboratory Co., Ltd., purity of 99.9 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that b was a value given in Table 1. [Example 13]

[0093] The sintered body of the ionically conductive solid containing the oxide of Example 13 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), MgO (manufactured by Ube Material Industries, Ltd., purity of 99.0 wt%) and CeO2 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that a and c were the values ​​given in Table 1. [Example 14]

[0094] The sintered body of the ionically conductive solid containing the oxide of Example 14 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, such that a and b were the values ​​given in Table 1. [Example 15]

[0095] The sintered body of the ionically conductive solid containing the oxide from Example 15 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), La2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity of 99.9 wt%), MgO (manufactured by Ube Material Industries, Ltd., purity of 99.0 wt%), and CaO (manufactured by KANTO CHEMICAL CO., INC., purity of 97.0 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts. was so that a and b were the values ​​given in Table 1. [Example 16]

[0096] The sintered body of the ionically conductive solid containing the oxide of Example 16 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), La2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity of 99.9 wt%) and MnO (manufactured by KANTO CHEMICAL CO., INC., purity of 80.0 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that a and b were the values ​​given in Table 1. [Example 17]

[0097] The sintered body of the ionically conductive solid containing the oxide of Example 17 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Tb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), and MnO (manufactured by KANTO CHEMICAL CO., INC., purity of 80.0 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that a and b were the values ​​given in Table 1. [Example 18]

[0098] The sintered body of the ionically conductive solid containing the oxide of Example 18 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Tm2O3 (manufactured by Kojundo Chemical Laboratory Co., Ltd., purity of 99.9 wt%) and CaO (manufactured by KANTO CHEMICAL CO., INC., purity of 97.0 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that a and b were the values ​​given in Table 1. [Example 19]

[0099] The sintered body of the ionically conductive solid containing the oxide of Example 19 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that c and d were the values ​​given in Table 1. [Example 20]

[0100] The sintered body of the ionically conductive solid containing the oxide, from Example 20, was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), In2O3 (manufactured by Shinko Chemical Co., Ltd., purity of 99 wt%), Nb2O5 (manufactured by MITSUI MINING & SMELTING CO., LTD, purity of 99.9%), and Ta2O5 (manufactured by KANTO CHEMICAL CO., INC., purity of 99 wt%) were used as raw materials, each raw material being used in stoichiometric amounts. was weighed so that b and d were the values ​​given in Table 1. [Example 21]

[0101] The sintered body of the ionically conductive solid containing the oxide of Example 21 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%) and Pr2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that b was a value given in Table 1. [Example 22]

[0102] The sintered body of the ionically conductive solid containing the oxide of Example 22 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that b and d were the values ​​given in Table 1. [Example 23]

[0103] The sintered body of the ionically conductive solid containing the oxide from Example 23 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Sm2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity of 99.9 wt%), HfO2 (manufactured by New Metals and Chemicals Corporation, Ltd., purity of 99.9%), and Ta2O5 (manufactured by KANTO CHEMICAL CO., INC., purity of 99 wt%) were used as raw materials, each raw material weighed in stoichiometric amounts. was so that b, c and d were the values ​​given in Table 2. [Example 24]

[0104] The sintered body of the ionically conductive solid containing the oxide from Example 24 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Nd2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Sm2O3 (manufactured by Wako Pure Chemical Industries, Ltd., purity of 99.9 wt%), HfO2 (manufactured by New Metals and Chemicals Corporation, Ltd., purity of 99.9 wt%) and ZnO (manufactured by Wako Pure Chemical Industries, Ltd., purity of 99 wt%) was used as raw materials, with each raw material being weighed in stoichiometric amounts such that a and b were the values ​​given in Table 2. [Example 25]

[0105] The sintered body of the ionically conductive solid containing the oxide of Example 25 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that b and c were the values ​​given in Table 2. [Example 26]

[0106] The sintered body of the ionically conductive solid containing the oxide of Example 26 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%) and Eu2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 95 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that b was a value given in Table 2. [Example 27]

[0107] The sintered body of the ionically conductive solid containing the oxide of Example 27 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Eu2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 95 wt%) and NiO (manufactured by Wako Pure Chemical Industries, Ltd., purity of 99.0 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts such that a and b were the values ​​given in Table 2. [Example 28]

[0108] The sintered body of the ionically conductive solid containing the oxide of Example 28 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that b and c were the values ​​given in Table 2. [Example 29]

[0109] The sintered body of the ionically conductive solid containing the oxide, from Example 29, was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Gd2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Dy2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 95 wt%), and CaO (manufactured by KANTO CHEMICAL CO., INC., purity of 99.0 wt%) were used as raw materials, each raw material in stoichiometric The quantities were weighed out so that a and b were the values ​​given in Table 2. [Example 30]

[0110] The sintered body of the ionically conductive solid containing the oxide of Example 30 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, so that b and c were the values ​​given in Table 2. [Example 31]

[0111] The sintered body of the ionically conductive solid containing the oxide of Example 31 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, such that b and c were the values ​​given in Table 2. [Example 32]

[0112] The sintered body of the ionically conductive solid containing the oxide of Example 32 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that b was a value given in Table 2. [Example 33]

[0113] The sintered body of the ionically conductive solid containing the oxide from Example 33 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Tb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), NiO (manufactured by Wako Pure Chemical Industries, Ltd., purity of 99.0 wt%), and BaO (manufactured by Wako Pure Chemical Industries, Ltd., purity of 90.0 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts. was so that a and b were the values ​​given in Table 2. [Example 34]

[0114] The sintered body of the ionically conductive solid containing the oxide from Example 34 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Tb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Ho2O3 (manufactured by Kojundo Chemical Laboratory Co., Ltd., purity of 99.9 wt%), and BaO (manufactured by Wako Pure Chemical Industries, Ltd., purity of 90.0 wt%) were used as raw materials, each raw material being in stoichiometric amounts. was weighed so that a and b were the values ​​given in Table 2. [Example 35]

[0115] The sintered body of the ionically conductive solid containing the oxide of Example 35 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that b, c and d were the values ​​given in Table 2. [Example 36]

[0116] The sintered body of the ionically conductive solid containing the oxide from Example 36 was prepared in the same step as in Example 1, except that Li3BO3 (manufactured by Toshima Manufacturing Co., Ltd., purity of 99.9 wt%), H3BO3 (manufactured by KANTO CHEMICAL CO., INC., purity of 99.5%), Yb2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 99.9 wt%), Er2O3 (manufactured by Shin-Etsu Chemical Co., Ltd., purity of 95 wt%), Tm2O3 (manufactured by Kojundo Chemical Laboratory Co., Ltd., purity of 99.9 wt%), and SrO (manufactured by Kojundo Chemical Laboratory Co., Ltd., purity of 98 wt%) were used as raw materials, each raw material being weighed in stoichiometric amounts. was so that a and b were the values ​​given in Table 2. [Example 37]

[0117] The sintered body of the ionically conductive solid containing the oxide of Example 37 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, such that b and c were the values ​​given in Table 2. [Example 38]

[0118] The sintered body of the ionically conductive solid containing the oxide of Example 38 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that a, b and c were the values ​​given in Table 2. [Example 39]

[0119] The sintered body of the ionically conductive solid containing the oxide of Example 39 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, such that b and d were the values ​​given in Table 2. [Example 40]

[0120] The sintered body of the ionically conductive solid containing the oxide of Example 40 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that b, c and d were the values ​​given in Table 2. [Example 41]

[0121] The sintered body of the ionically conductive solid containing the oxide of Example 41 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that a, b and c were the values ​​given in Table 2. [Example 42]

[0122] The sintered body of the ionically conductive solid containing the oxide of Example 42 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, such that b and d were the values ​​given in Table 2. [Example 43]

[0123] The sintered body of the ionically conductive solid containing the oxide of Example 43 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts, such that b and d were the values ​​given in Table 2. [Example 44]

[0124] The sintered body of the ionically conductive solid containing the oxide of Example 44 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that a and b were the values ​​given in Table 2, and that a disk speed was set to 300 rpm during pulverization. [Example 45]

[0125] The sintered body of the ionically conductive solid containing the oxide of Example 45 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that a and b were the values ​​given in Table 2, and that a disk speed was set to 300 rpm during pulverization. [Example 46]

[0126] The sintered body of the ionically conductive solid containing the oxide of Example 46 was prepared in the same step as in Example 1, except that each raw material used in the examples described above was weighed in stoichiometric amounts such that a and b were the values ​​given in Table 2, and that a disk speed was set to 300 rpm during pulverization. [Comparison example 1]

[0127] The sintered body of the ionically conductive solid containing the oxide of Comparative Example 1 was prepared in the same step as in Example 1, except that Yb2O3 as the raw material in Example 1 was replaced by Y2O3, and each raw material was weighed in stoichiometric amounts, so that d was a value given in Table 1. [Comparative example 2]

[0128] The sintered body of the ionically conductive solid containing the oxide of Comparative Example 2 was prepared in the same step as in Example 2, except that Yb2O3 as the raw material in Example 2 was replaced by Y2O3, and each raw material was weighed in stoichiometric amounts, so that c was a value given in Table 1. [Comparative example 3]

[0129] The sintered body of the ionically conductive solid containing the oxide from Comparative Example 3 was prepared in the same step as in Example 3, except that Yb2O3 as the raw material in Example 3 was replaced by Y2O3, and each raw material was weighed in stoichiometric amounts, so that c and d were the values ​​given in Table 1.

[0130] The sintered bodies of the ionically conductive solids containing the oxides from Examples 1 to 46 were subjected to composition analysis according to the procedures described above. Furthermore, the volume-averaged particle diameters of the powders of the ionically conductive solids obtained in Examples 1 to 46 and the comparison examples 1 to 3, as well as the ionic conductivities of the sintered bodies of the ionically conductive solids, were measured according to the following procedures.

[0131] The procedures for measuring the ionic conductivities and the volume-averaged particle diameters are described below. The evaluation results are also listed in Tables 1 and 2. -Measurement of ionic conductivity

[0132] Two parallel, large-area surfaces of the secondary-firing ionically conductive solid, comprising the oxide, which have a flat, plate-like shape, were polished with abrasive paper. The size of the sintered body of the ionically conductive solid, comprising the oxide and having the flat plate shape, can be set to, for example, 0.9 cm × 0.9 cm × 0.05 cm, but is 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, and was complete when no noticeable depression / protrusion or defect was visually observed on the polished surfaces.

[0133] After polishing, gold was deposited onto the polished surfaces of the sintered body of the ionically conductive solid containing the oxide using a Sanyu Electron Co. Ltd. SC-701MkII ADVANCE sputtering unit. A sample was prepared with the following deposition conditions: Ar as the process gas, a vacuum of 2 Pa to 5 Pa, and a deposition time of 5 minutes. The AC impedance of the sample was then measured.

[0134] For the impedance measurement, an SI1260 impedance / gain phase analyzer and a 1296 dielectric interface system (both manufactured by Solartron) were used, and the measurement conditions were set to a temperature of 27°C, an amplitude of 20 mV and a frequency of 0.1 Hz to 1 MHz.

[0135] The resistance of the sintered body of the ionically conductive solid containing the oxide was calculated using a Nyquist plot obtained from impedance measurements and ZVIEW AC analysis software manufactured by Scribner. ZVIEW generated an equivalent circuit corresponding to the measured sample and performed the fitting and analysis of the equivalent circuit and the Nyquist plot to calculate the resistance of the sintered body of the ionically conductive solid containing the oxide. The ionic conductivity was calculated using the following equation, the calculated resistance, the thickness of the sintered body of the ionically conductive solid containing the oxide, and an electrode area. Ionic conductivity (S / cm) = Thickness (cm) of the sintered body containing oxide / (Resistance (Ω) of the sintered body containing oxide × Electrode area (cm²))

[0136] The ionic conductivity (S / cm) of the sintered body of the ionically conductive solid is, for example, preferably 8.00 × 10 -9 or more, preferably 1.00 × 10 -8 or more, even more preferred 1.00 × 10 -7 or more, preferably 1.00 × 10 -6 or more, and especially preferably 1.00 × 10 -5 or more. A higher conductivity is preferred, the upper limit of which is not particularly restricted and is, for example, 1.00 × 10⁻⁶. -2 or less, 1.00 × 10 -3 or less and 1.00 × 10 -4 or less. -Evaluation of the volume-averaged particle diameter

[0137] The particle size distribution of the powder of the ionically conductive solid containing the oxide, obtained by treatment in a ball mill (planetary mill P-7, manufactured by Fritsch GmbH) after initial firing, was measured using a laser diffraction / scattering instrument LA-960V2, manufactured by HORIBA, Ltd. The refractive index was set to 1.8, and ethanol was used as the measuring solvent. The sample concentration was adjusted to achieve a transmittance of 70% to 90%. The volume-averaged particle diameter was calculated from the obtained frequency distribution. -Results

[0138] The stoichiometric sets (values ​​of a, b, c, and d in the general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 dB3O9) of the raw materials, the volume-averaged particle diameters and the ionic conductivities in the case of the production of each of the sintered bodies of the ionically conductive solids having the oxides, of Examples 1 to 46 and of Comparative Examples 1 to 3 are listed in Table 1.

[0139] As a result of the composition analysis described above, it was confirmed that all sintered bodies of the ionically conductive solids containing the oxides, Examples 1 to 46 and Comparative Examples 1 to 3, exhibited the compositions in the stoichiometric amounts of the raw materials listed in Table 1. Furthermore, the sintered bodies of the ionically conductive solids containing the oxides, Examples 1 to 46, were ionically conductive solids exhibiting high ionic conductivities, even when firing was carried out at a temperature of less than 700°C. [Table 1] Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 d B3O9 Average diameter [µm] Ionic conductivity [S / cm] M1 M2 M3 M4 a b c d Comparative example 1 - - - Note 0 0 0 0,400 10,1 5,65×10 -10 Comparative example 2 - - Ce - 0 0 0,300 0 21,3 2,66×10 -8 Comparative example 3 - - Zr:Ce=1:1 Note 0 0 0,200 0,100 15,1 8,73×10 -8 Example 1 - - - Note 0 0 0 0,400 11,6 3,11×10 -7 Example 2 - - Ce - 0 0 0,300 0 13,5 4,89×10 -7 Example 3 - - Zr:Ce=1:1 Note 0 0 0,200 0,100 16,9 5,04×10 -7 Example 4 - - - - 0 0 0 0 15,1 1,10×10 -7 Example 5 - - Hf - 0 0 0,100 0 9,6 5,63×10 -6 Example 6 - - Zr:Ce=4:1 - 0 0 0,125 0 9,3 5,72×10 -5 Example 7 - - Zr Note 0 0 0,100 0,025 0,3 3,07×10 -5 Example 8 - In Sn - 0 0,500 0,400 0 8,4 2,56×10 -7 Example 9 - In Hf - 0 0,300 0,100 0 8,5 6,68×10 -6 Example 10 - Fe Ti - 0 0,100 0,800 0 8,5 1,03×10 -8 Example 11 - Fe Zr:Hf=4:1 - 0 0,400 0,100 0 7,9 4,21×10 -6 Example 12 - Lu - - 0 0,900 0 0 9,0 5,47×10 -\6 Example 13 Mg - Ce - 0,025 0 0,025 0 16,3 1,98×10 -6 Example 14 Mg Lu - - 0,025 0,800 0 0 8,1 6,44×10 -6 Example 15 Mg:Ca=1:1 La - - 0,100 0,800 0 0 8,0 8,33×10 -1 Example 16 Mn La - - 0,800 0,100 0 0 7,7 6,11×10 -8 Example 17 Mn Tb - - 0,050 0,100 0 0 20,9 1,53×10 -7 Example 18 Approx Tm - - 0,050 0,100 0 0 18,3 1,87×10 -7 Example 19 - - Sn Note 0 0 0,100 0,400 11,5 3,77×10 -7 Example 20 - In - Nb:Ta=1:1 0 0,300 0 0,100 8,6 5,91×10 -6 Example 21 - Pr - - 0 0,500 0 0 10,6 2,74×10 -8 Example 22 - Pr:La=1:1 - Note 0 0,100 0 0,800 9,7 7,05×10 -9 [Table 2] Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 d B3O9 Average diameter [µm] Ionic conductivity [S / cm] M1 M2 M3 M4 a b c d Example 23 - Sm Hf Ta 0 0,500 0,050 0,050 8,1 4,69×10 -7 Example 24 Zn Nd:Sm=1:1 - - 0,100 0,200 0 0 8,3 3,58×10 -7 Example 25 - Nd Zr - 0 0,100 0,100 0 12,4 9,14×10 -6 Example 26 - Eu - - 0 0,100 0 0 14,2 1,01×10 -7 Example 27 Ni Eu - - 0,100 0,100 0 0 23,3 1,96×10 -7 Example 28 - Eu Zr:Hf=4:1 - 0 0,100 0,100 0 11,9 7,59×10 -6 Example 29 Approx Gd:Dy=1:1 - - 0,100 0,200 0 0 9,5 4,31×10 -7 Example 30 - Gd Zr - 0 0,100 0,100 0 9,1 1,65×10 -5 Example 31 - Dy Ti:Sn=1:1 - 0 0,100 0,100 0 12,6 6,88×10 -6 Example 32 - Dy - - 0 0,100 0 0 8,7 7,13×10 -8 Example 33 Ba:Ni=1:1 Tb - - 0,100 0,100 0 0 26,4 2,81×10 -7 Example 34 Ba Tb:Ho=1:1 - - 0,100 0,200 0 0 14,1 3,88×10 7 Example 35 - Tb Hf Ta 0 0,100 0,050 0,050 8,2 6,69×10 -7 Example 36 Sr Er:Tm=1:1 - - 0,100 0,200 0 0 9,8 4,79×10 -7 Example 37 - Er Ti - 0 0,100 0,100 0 10,8 1,77×10 -7 Example 38 Ni Er Sn - 0,100 0,100 0,100 0 9,9 1,86×10 -7 Example 39 - Tm - Note 0 0,100 0 0,100 8,5 1,42×10 -7 Example 40 - Tm Zr Ta 0 0,100 0,100 0,100 9,5 7,82×10 -6 Example 41 Mg Gd Ce - 0,100 0,100 0,100 0 8,2 5,26×10 7 Example 42 - Gd - Note 0 0,010 0 0,100 10,2 1,46×10 -7 Example 43 - Gd - Ta 0 0,100 0 0,800 11,2 5,01×10 -9 Example 44 Mn Tb - - 0,050 0,100 0 0 10,7 3,67×10 -7 Example 45 Ni Eu - - 0,100 0,100 0 0 16,8 3,94×10 -7 Example 46 Ba:Ni=1:1 Tb - - 0,100 0,100 0 0 12,2 4,55×10 -7

[0140] In Tables 1 and 2, the ionic conductivities of the ionically conductive solids produced in Examples 1 to 3 were improved compared to those in the comparison examples 1 to 3, indicating that higher ionic conductivity can be achieved by substituting Y with Yb. The substitution of Y in the composition disclosed in the related prior art with Yb having a smaller ionic radius leads to higher ionic conductivity.

[0141] Tables 1 and 2 show the results in which the ionically conductive solids produced in Examples 44 to 46 were improved compared to those in Examples 17, 27, and 33, respectively. Since the compositions of the substituted elements differ from those disclosed in the prior art, the suitable ranges of particle diameters may differ due to variations in melting points and other factors affecting the densities after firing. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 6948676 [0009, 0018, 0019] Cited non-patent literature

[0000] Solid State Ionic 288 (2016) 248-252

[0008]

Claims

[1] Ion-conductive solid having an oxide represented by a general formula: Li 6+a-c-2d Yb 1-a-b-c-d M1 a M2 b M3 c M4 d 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, Lu, In and Fe, M3 is at least one metal element selected from the group consisting of Zr, Ce, Hf, Sn and Ti, M4 is at least one metal element selected from the group consisting of Nb and Ta, and a is 0.000 ≤ a ≤ 0.800, b is 0.000 ≤ 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 0.000 ≤ a + b + c + d < 1.000). [2] The ion-conductive solid according to claim 1, wherein the 1-abcd is 0.300 ≤ 1-abcd. [3] The ion-conductive solid according to claim 1 or 2, wherein the 1-abcd is 0.500 ≤ 1-abcd. [4] The ion-conductive solid according to any one of claims 1 to 3, wherein a is 0.000 ≤ a ≤ 0.

400. [5] The ion-conductive solid according to any one of claims 1 to 4, wherein b is 0.000 ≤ b ≤ 0.

500. [6] The ion-conductive solid according to any one of claims 1 to 5, wherein c is 0.000 ≤ c ≤ 0.

400. [7] The ion-conductive solid according to any one of claims 1 to 6, wherein d 0.000 ≤ d ≤ 0.

400. [8] The ion-conductive solid according to any one of claims 1 to 7, wherein the ion-conductive solid has a volume-average particle diameter of 0.1 µm or more and 28.0 µm or less. [9] Solid-state battery comprising at least: a cathode; an anode; and an electrolyte, wherein at least one selected from the group consisting of the cathode, the anode and the electrolyte comprises the ion-conductive solid according to any one of claims 1 to 8. [10] The solid-state battery according to claim 9, wherein at least the electrolyte comprises the ion-conductive solid.