Solid-state batteries and electronic devices

Abstract

The present invention provides an electronic device and a solid-state battery having high adhesion to terminal electrodes. The present invention comprises: a battery element body 140 having a positive electrode layer 110, a negative electrode layer 120, and a solid electrolyte layer 130; and terminal electrodes 151, 152 provided to end surfaces of the battery element body 140 and electrically connected to the battery element body 140, wherein the terminal electrodes 151, 152 contain a conductive material and a polyester resin.

Description

[Technical Field]

[0001] The present disclosure relates to solid-state batteries and electronic devices. [Background technology]

[0002] Secondary batteries that can be repeatedly charged and discharged have been used for a variety of purposes, including as power sources for electronic devices such as smartphones and laptops.

[0003] In secondary batteries, a liquid electrolyte is generally used as a medium for ion migration, which contributes to charging and discharging. In other words, a so-called electrolytic solution is used in secondary batteries. However, such secondary batteries generally require safety in terms of preventing leakage of the electrolytic solution. In addition, organic solvents and the like used in the electrolytic solution are flammable, so safety is also required in this respect.

[0004] Therefore, research is being conducted on solid-state batteries that use solid electrolytes instead of liquid electrolytes. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-220107 [Patent Document 2] Special Publication No. 2010-503957 Summary of the Invention [Problem to be solved by the invention]

[0006] A solid-state battery has an element body including battery constituent units each consisting of a positive electrode layer, a negative electrode layer, and a solid electrolyte therebetween, and is provided with terminal electrodes electrically connected to the positive electrode layer and the negative electrode layer, respectively. Here, Patent Document 1 describes that a highly conductive material is selected for the terminal electrodes, and silver, gold, platinum, aluminum, copper, tin, and nickel are used.

[0007] However, there has been a demand for further improvements in the electrical properties and reliability of solid-state batteries.

[0008] The present disclosure has been made in view of such a demand. That is, a main object of the present disclosure is to provide a solid-state battery and an electronic device having high adhesion to the terminal electrodes of the solid-state battery. [Means for solving the problem]

[0009] The inventors of the present invention attempted to solve the above problems by taking a new approach rather than simply extending the conventional technology, and as a result, they have developed a solid-state battery that achieves the above-mentioned main objective.

[0010] The solid-state battery according to the present disclosure comprises: a battery element having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer interposed between the positive electrode layer and the negative electrode layer; a terminal electrode provided on an end surface of the battery body and electrically connected to the battery body, The terminal electrode includes a conductive material and a polyester resin.

[0011] The electronic device according to the present disclosure has the above-described solid-state battery surface-mounted. [Effects of the Invention]

[0012] According to the solid-state battery and electronic device according to the present disclosure, it is possible to provide a solid-state battery and electronic device having high adhesiveness with respect to the terminal electrodes. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a cross-sectional view of a main part of a solid-state battery according to the present disclosure. [Figure 2A] FIG. 1 is a schematic diagram of a solid-state battery according to the present disclosure. [Figure 2B] FIG. 1 is a schematic diagram of a solid-state battery according to the present disclosure. [Figure 3] FIG. 1 is a cross-sectional view of a solid-state battery according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] The "solid-state battery" and the "electronic device" having the surface-mounted solid-state battery of the present disclosure will be described in detail below. While the description will be made with reference to the drawings as needed, the contents shown in the drawings are merely shown as schematic examples for the purpose of understanding the present disclosure, and the appearance and dimensional ratios may differ from the actual product.

[0015] First, a "solid-state battery" according to an embodiment of the present disclosure will be described. In the present disclosure, the term "solid-state battery" broadly refers to a battery whose components are made of solids, and in the narrow sense refers to an all-solid-state battery whose battery components (particularly preferably all battery components) are made of solids. In a preferred embodiment, the solid-state battery according to the present disclosure is a stacked solid-state battery in which each layer constituting a battery unit is stacked on top of each other, and preferably each such layer may be a fired body. Note that the term "solid-state battery" encompasses not only so-called "secondary batteries" that can be repeatedly charged and discharged, but also "primary batteries" that can only be discharged. According to a preferred embodiment of the present disclosure, the "solid-state battery" is a secondary battery. The term "secondary battery" should not be overly constrained by its name, and may also encompass, for example, an electricity storage device.

[0016] As used herein, a "planar view" refers to the shape of an object viewed from above or below along the thickness direction, which is the stacking direction of each layer constituting a solid-state battery. Furthermore, a "cross-sectional view" refers to the shape of an object viewed from a direction substantially perpendicular to the thickness direction, which is the stacking direction of each layer constituting a solid-state battery (in other words, the shape of an object cut along a plane parallel to the thickness direction). The terms "vertical direction" and "horizontal direction" used directly or indirectly in this specification correspond to the vertical direction and horizontal direction in the drawings, respectively. Unless otherwise specified, the same symbols or symbols refer to the same components or parts or have the same meaning. In a preferred embodiment, the vertical downward direction (i.e., the direction in which gravity acts) can be considered to correspond to the "downward direction," and the opposite direction can be considered to correspond to the "upward direction."

[0017] [Solid-state battery configuration] The solid-state battery 100 has a battery element 140 including battery constituent units each consisting of a positive electrode layer 110, a negative electrode layer 120, and at least a solid electrolyte layer 130 interposed therebetween, and terminal electrodes 151 and 152 (see FIG. 1). More specifically, the terminal electrodes 151 and 152 are in contact with the outer surface of the battery element 140.

[0018] 1. Battery element The layers constituting the battery element 140 may be formed by firing. The positive electrode layer 110, the negative electrode layer 120, and the solid electrolyte layer 130 may form sintered layers. Preferably, the positive electrode layer, the negative electrode layer, and the solid electrolyte may be integrally fired to form a sintered body. Therefore, the battery element may form an integral sintered body. In this specification, the direction in which the positive electrode layers and the negative electrode layers are stacked (vertical direction) is referred to as the "stacking direction," and the direction intersecting with the stacking direction is the horizontal direction in which the positive electrode layers and the negative electrode layers extend.

[0019] 1-1. Positive electrode layer and negative electrode layer The positive electrode layer 110 is an electrode layer including at least a positive electrode active material layer 111. The positive electrode layer 110 may further include a solid electrolyte. In a preferred embodiment, the positive electrode layer 110 may be composed of a sintered body including at least positive electrode active material particles and solid electrolyte particles. On the other hand, the negative electrode layer 120 may be an electrode layer including at least a negative electrode active material layer 121. The negative electrode layer 120 may further include a solid electrolyte. In a preferred embodiment, the negative electrode layer 120 may be composed of a sintered body including at least a negative electrode active material particles and solid electrolyte particles.

[0020] Here, the positive electrode active material and the negative electrode active material are materials involved in the exchange of electrons in a solid-state battery. Charging and discharging are performed by the movement (or conduction) of ions between the positive electrode layer and the negative electrode layer via the solid electrolyte, and the exchange of electrons between the positive electrode layer and the negative electrode layer via external terminals. The positive electrode layer 110 and the negative electrode layer 120 may also include a current collector layer.

[0021] 1 shows an example of a configuration in which three positive electrode layers 110 and two negative electrode layers 120 are stacked, but the number of layers is not limited to this example and may be one layer, or several tens to several hundreds of layers. The thickness of the positive electrode layer or the negative electrode layer may be 5 μm or more and 60 μm or less, preferably 8 μm or more and 50 μm or less. It may also be 5 μm or more and 30 μm or less.

[0022] (Cathode active material layer) The positive electrode active material contained in the positive electrode active material layer 111 is, for example, a lithium-containing compound or a sodium-containing compound. In other words, it may be capable of absorbing and releasing lithium ions or sodium ions. The type of lithium-containing compound is not particularly limited, and may be, for example, a lithium transition metal composite oxide and / or a lithium transition metal phosphate compound. Lithium transition metal composite oxide is a general term for oxides containing lithium and one or more transition metal elements as constituent elements. Lithium transition metal phosphate compound is a general term for phosphate compounds containing lithium and one or more transition metal elements as constituent elements. The type of transition metal element is not particularly limited, and may be, for example, cobalt (Co), nickel (Ni), manganese (Mn), and / or iron (Fe).

[0023] The lithium transition metal composite oxide is, for example, Li x M1O2 and Li y Lithium transition metal phosphate compounds include compounds represented by the formula: Li z The compounds are represented by the formula M3PO4, where M1, M2, and M3 each represent one or more transition metal elements, and the values ​​of x, y, and z are arbitrary.

[0024] Specifically, the lithium transition metal composite oxide is, for example, LiCoO2, LiNiO2, LiVO2, LiCrO2, LiMn2O4, LiCo 1 / 3 Ni 1 / 3 Mn 1 / 3 O2, and LiNi 0.5 Mn 1.5O4, etc. Examples of lithium transition metal phosphate compounds include LiFePO4, LiCoPO4, and LiMnPO4. Lithium transition metal composite oxides (particularly LiCoO2) may contain trace amounts (of the order of a few percent) of additive elements. Examples of additive elements include one or more elements selected from the group consisting of aluminum (Al), magnesium (Mg), nickel (Ni), manganese (Mn), titanium (Ti), boron (B), vanadium (V), chromium (Cr), iron (Fe), copper (Cu), zinc (Zn), molybdenum (Mo), tin (Sn), tungsten (W), zirconium (Zr), yttrium (Y), niobium (Nb), calcium (Ca), strontium (Sr), bismuth (Bi), sodium (Na), potassium (K), and silicon (Si).

[0025] In addition, the positive electrode active material capable of absorbing and releasing sodium ions may be at least one selected from the group consisting of sodium-containing phosphate compounds having a Nasicon structure, sodium-containing phosphate compounds having an olivine structure, sodium-containing layered oxides, and sodium-containing oxides having a spinel structure. For example, in the case of sodium-containing phosphate compounds, at least one selected from the group consisting of Na3V2(PO4)3, NaCoFe2(PO4)3, Na2Ni2Fe(PO4)3, Na3Fe2(PO4)3, Na2FeP2O7, Na4Fe3(PO4)2(PO2O7), and as a sodium-containing layered oxide, NaFeO2 may be used.

[0026] Alternatively, the positive electrode active material may be, for example, an oxide, a disulfide, a chalcogenide, or a conductive polymer. The oxide may be, for example, titanium oxide, vanadium oxide, or manganese dioxide. The disulfide may be, for example, titanium disulfide or molybdenum sulfide. The chalcogenide may be, for example, niobium selenide. The conductive polymer may be, for example, a disulfide, polypyrrole, polyaniline, polythiophene, polyparastyrene, polyacetylene, or polyacene.

[0027] The content of the positive electrode active material in the positive electrode active material layer 111 is usually 50% by weight or more, for example 60% by weight or more, relative to the total amount of the positive electrode active material layer 111. The positive electrode active material layer 111 may contain two or more types of positive electrode active materials, in which case the total content thereof may be within the above range. When the content of the active material is 50% by weight or more, the energy density of the battery can be particularly increased.

[0028] (Negative electrode active material layer) The negative electrode active material contained in the negative electrode active material layer 121 is, for example, a carbon material, a metal-based material, a lithium alloy and / or a lithium-containing compound.

[0029] Specifically, the carbon material is, for example, graphite, graphitizable carbon, non-graphitizable carbon, mesocarbon microbeads (MCMB) and / or highly oriented graphite (HOPG).

[0030] Metallic materials are a general term for materials containing, as constituent elements, one or more of metal elements and semimetal elements that can form an alloy with lithium. This metallic material may be a simple substance, an alloy, or a compound. The purity of the simple substance described here is not necessarily limited to 100%, and the simple substance may contain trace amounts of impurities.

[0031] Metal elements and metalloid elements include, for example, silicon (Si), tin (Sn), aluminum (Al), indium (In), magnesium (Mg), boron (B), gallium (Ga), germanium (Ge), lead (Pb), bismuth (Bi), cadmium (Cd), titanium (Ti), chromium (Cr), iron (Fe), niobium (Nb), molybdenum (Mo), silver (Ag), zinc (Zn), hafnium (Hf), zirconium (Zr), yttrium (Y), palladium (Pd) and / or platinum (Pt).

[0032] Specifically, the metal-based material may be, for example, Si, Sn, SiB4, TiSi2, SiC, Si3N4, or SiO v (0 <v≦2)、LiSiO、SnOw (0 <w≦2)、SnSiO3、LiSnOおよび / またはMg2Snなどである。

[0033] The lithium-containing compound is, for example, a lithium transition metal composite oxide. The definition of the lithium transition metal composite oxide is as described above. Specifically, the lithium transition metal composite oxide is, for example, Li3V2(PO4)3, Li3Fe2(PO4)3, Li4Ti5O 12 , LiTi2(PO4)3, and / or LiCuPO4.

[0034] In addition, the negative electrode active material capable of absorbing and releasing sodium ions may be at least one selected from the group consisting of sodium-containing phosphate compounds having a Nasicon structure, sodium-containing phosphate compounds having an olivine structure, and sodium-containing oxides having a spinel structure.

[0035] The content of the negative electrode active material in the negative electrode active material layer 121 is usually 50% by weight or more, for example 60% by weight or more, relative to the total amount of the negative electrode active material portion. The negative electrode active material portion may contain two or more types of negative electrode active materials, in which case the total content thereof may be within the above range. By making the content of the active material 50% by weight or more, the energy density of the battery can be particularly increased.

[0036] (Additional Configuration of Positive Electrode Active Material Layer and Negative Electrode Active Material Layer) The positive electrode active material layer 111 and / or the negative electrode active material layer 121 may contain a conductive material. Examples of the conductive material contained in the positive electrode active material layer 111 and / or the negative electrode active material layer 121 include carbon materials and metal materials. Specifically, examples of the carbon materials include graphite and carbon nanotubes. Examples of the metal materials include copper (Cu), magnesium (Mg), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), indium (In), gold (Au), platinum (Pt), silver (Ag), and / or palladium (Pd), and may also be alloys of two or more of these metals.

[0037] The positive electrode active material layer 111 and / or the negative electrode active material layer 121 may contain a binder. The binder may be, for example, one or more of synthetic rubber and polymeric materials. Specifically, the synthetic rubber may be, for example, styrene-butadiene rubber, fluorine-containing rubber, and / or ethylene propylene diene. The polymeric material may be, for example, at least one selected from the group consisting of polyvinylidene fluoride, polyimide, and acrylic resin.

[0038] The positive electrode active material layer 111 and / or the negative electrode active material layer 121 may contain a sintering aid. The sintering aid may be at least one selected from the group consisting of lithium oxide, sodium oxide, potassium oxide, boron oxide, silicon oxide, bismuth oxide, and phosphorus oxide.

[0039] There are no particular limitations on the thickness of each of the positive electrode active material layer 111 and the negative electrode active material layer 121, and for example, each may independently be 2 μm or more and 100 μm or less, and particularly 5 μm or more and 50 μm or less.

[0040] (Positive electrode current collector layer and negative electrode current collector layer) The positive electrode current collector layer 112 and the negative electrode current collector layer 122 preferably have higher electronic conductivity than the positive electrode active material layer 111 and the negative electrode active material layer 121 .

[0041] The positive electrode current collector layer 112 may be made of, for example, at least one material selected from the group consisting of carbon materials, silver, palladium, gold, platinum, aluminum, copper, nickel-lithium transition metal composite oxides, and lithium-transition metal phosphate compounds.

[0042] The negative electrode current collector layer 122 may be made of, for example, at least one material selected from the group consisting of carbon materials, silver, palladium, gold, platinum, aluminum, copper, and nickel.

[0043] The positive electrode current collector layer 112 and / or the negative electrode current collector layer 122 may each have an electrical connection portion for electrical connection to the outside, and may be configured to be electrically connectable to a terminal electrode. The positive electrode current collector layer 112 and the negative electrode current collector layer 122 may each be in the form of a foil, but from the viewpoint of improving conductivity and reducing manufacturing costs by sintering them together, they are preferably in the form of an integrated sintering.

[0044] When the positive electrode current collector layer 112 and / or the negative electrode current collector layer 122 have the form of a sintered body, they may be composed of a sintered body containing, for example, a conductive material, an active material, a solid electrolyte, a binder, and / or a sintering aid. The conductive material contained in the positive electrode current collector layer 112 and the negative electrode current collector layer 122 may be selected from, for example, the same materials as the conductive material that may be contained in the positive electrode active material layer 111 and / or the negative electrode active material layer 121. Note that the positive electrode current collector layer 112 and the negative electrode current collector layer 122 are not necessarily required for a solid-state battery, and a solid-state battery without such a positive electrode current collector layer 112 and a negative electrode current collector layer 122 may also be used. In other words, the solid-state battery in the present disclosure may be a solid-state battery without a current collector layer.

[0045] The positive electrode current collector layer 112 and / or the negative electrode current collector layer 122 may contain a heat-resistant resin. When the current collector layer contains a heat-resistant resin, cracks caused by expansion of the current collector layer can be suppressed.

[0046] There are no particular limitations on the thickness of each of the positive electrode current collector layer 112 and the negative electrode current collector layer 122, and for example, each may independently be 1 μm or more and 100 μm or less, and particularly 1 μm or more and 50 μm or less.

[0047] 1-2.Solid electrolyte layer The solid electrolyte constituting the solid electrolyte layer 130 is a material capable of conducting lithium ions or sodium ions. In particular, the solid electrolyte constituting the battery constituent unit in a solid-state battery forms a layer capable of conducting lithium ions or sodium ions between the positive electrode layer 110 and the negative electrode layer 120. The solid electrolyte layer only needs to be provided between the positive electrode layer 110 and the negative electrode layer 120. In other words, the solid electrolyte layer may also be present around the positive electrode layer 110 and / or the negative electrode layer 120 so as to extend horizontally from between the positive electrode layer 110 and the negative electrode layer 120. Specific solid electrolytes include, for example, one or more of a crystalline solid electrolyte, a glass-based solid electrolyte, and a glass-ceramic-based solid electrolyte.

[0048] Crystalline solid electrolytes include, for example, oxide-based crystalline materials and sulfide-based crystalline materials. Examples of oxide-based crystalline materials include lithium-containing phosphate compounds having a Nasicon structure, oxides having a perovskite structure, oxides having a garnet or garnet-like structure, and oxide glass ceramic-based lithium ion conductors. Examples of lithium-containing phosphate compounds having a Nasicon structure include Li x M y (PO4)3 (1≦x≦2, 1≦y≦2, M is at least one selected from the group consisting of titanium (Ti), germanium (Ge), aluminum (Al), gallium (Ga) and zirconium (Zr)). An example of a lithium-containing phosphate compound having a Nasicon structure is, for example, Li 1.2 Al 0.2 Ti 1.8 (PO4)3, etc. An example of an oxide with a perovskite structure is La 0.55 Li 0.35 Examples of oxides with garnet or garnet-like structures include Li7La3Zr2O 12 Examples of sulfide-based crystal materials include thio-LISICON, for example, Li 3.25 Ge 0.25 P 0.75 S4 and Li 10 GeP2S12 The crystalline solid electrolyte may include a polymer material (for example, polyethylene oxide (PEO)).

[0049] Examples of glass-based solid electrolytes include oxide-based glass materials and sulfide-based glass materials, such as Li2O-SiO2, Li2O-Al2O3-TiO2-P2O5, 54Li2O·11SiO2·35B2O3, 50Li4SiO4·50Li3BO3, 23.3Li2O-76.7GeO2, and 60Li2O-40P2O. 5、 In other words, the oxide-based glass material may contain at least one element selected from the group consisting of lithium, silicon, and boron. The oxide-based glass material essentially contains lithium oxide and may contain at least one element selected from the group consisting of germanium oxide, silicon oxide, boron oxide, and phosphorus oxide. Examples of sulfide-based glass materials include 30Li2S·26B2S3·44LiI, 63Li2S·36SiS2·1Li3PO4, 57Li2S·38SiS2·5Li4SiO4, 70Li2S·30P2S5, and 50Li2S·50GeS2.

[0050] The glass ceramic solid electrolyte is, for example, an oxide-based glass ceramic material or a sulfide-based glass ceramic material. As the oxide-based glass ceramic material, for example, a phosphate compound containing lithium, aluminum, and titanium as constituent elements (LATP) or a phosphate compound containing lithium, aluminum, and germanium as constituent elements (LAGP) can be used. LATP is, for example, Li 1.07 Al 0.69 Ti 1.46 (PO4)3, etc. Also, LAGP is, for example, Li 1.5 Al 0.5 Ge 1.5(PO4), etc. In other words, the oxide-based glass ceramic material may contain at least one selected from the group consisting of lithium, silicon, and boron. For example, 90Li3BO3-10Li2SO4 may be mentioned. Furthermore, the oxide-based glass ceramic material essentially contains lithium oxide, and may contain at least one selected from the group consisting of germanium oxide, silicon oxide, boron oxide, and phosphorus oxide. Furthermore, the sulfide-based glass ceramic material may be, for example, Li7P3S 11 and Li 3.25 P 0.95 Examples include S4.

[0051] When emphasis is placed on the viewpoint of excellent atmospheric stability and ease of integral sintering, the solid electrolyte may contain at least one material selected from the group consisting of an oxide-based crystalline material, an oxide-based glass material, and an oxide-based glass ceramic material.

[0052] In addition, examples of solid electrolytes capable of conducting sodium ions include sodium-containing phosphate compounds having a Nasicon structure, oxides having a perovskite structure, and oxides having a garnet or garnet-like structure. Examples of sodium-containing phosphate compounds having a Nasicon structure include Na x M y (PO4)3 (1≦x≦2, 1≦y≦2, M is at least one selected from the group consisting of Ti, Ge, Al, Ga and Zr).

[0053] The solid electrolyte layer may contain a binder and / or a sintering aid. The binder and / or sintering aid contained in the solid electrolyte layer may be selected from, for example, materials similar to the binder and / or sintering aid that may be contained in the positive electrode active material portion and / or the negative electrode active material portion.

[0054] The thickness of the solid electrolyte layer is not particularly limited, and may be, for example, 1 μm or more and 15 μm or less, and particularly 1 μm or more and 5 μm or less.

[0055] 2.Terminal electrode The terminal electrodes are provided on the end surfaces of the battery body 140. As an example, in FIG. 1, terminal electrodes 151, 152 may be provided on each side surface of the battery body 140 that is positioned in a direction intersecting the stacking direction of the battery body 140. As a modified example of the terminal electrodes 151, 152, as shown in FIG. 2A, they may extend from the side surface of the battery body 140 to the bottom surface of the battery body. As another modified example, as shown in FIG. 2B, the terminal electrodes may be provided from the side surface to the bottom surface and / or top surface of the battery body 140.

[0056] More specifically, the terminal electrodes include a positive electrode side terminal electrode 151 connected to the positive electrode layer 110 and a negative electrode side terminal electrode 152 connected to the negative electrode layer 120, and the positive electrode side terminal electrode 151 may be formed on one side surface (the right side in FIG. 1), and the negative electrode side terminal electrode 152 may be provided so as to face the positive electrode side terminal electrode 151 (the left side in FIG. 1).

[0057] The terminal electrodes 151, 152 contain a conductive material and a polyester-based resin. Conventional terminal electrodes for solid-state batteries are made solely of a conductive material. These terminal electrodes are formed by applying a conductive paste to a battery body and firing the conductive paste. Because the firing temperature for the conductive paste is approximately 800°C, it is unsuitable for battery bodies containing glass, which has a lower firing temperature. Therefore, in order to lower the temperature at which the terminal electrodes are formed, terminal electrodes containing a conductive material and a resin material are used. In particular, the inclusion of a polyester-based resin in the material forming the terminal electrodes can reduce the risk of cracks occurring in the terminal electrodes due to volume expansion that occurs when the solid-state battery is charged. Terminal electrodes are described in detail below.

[0058] (Conductive materials) The conductive material is a material having electrical conductivity, and specific examples thereof include carbon materials and metal materials. In this specification, "conductive" means a material having a volume resistivity of 10 7 This means that the resistance is Ω·cm or less.

[0059] The metal material is not particularly limited as long as it is conductive, but examples thereof include at least one selected from the group consisting of silver, gold, platinum, aluminum, copper, palladium, zinc, tin, and nickel. Composite metals such as Ag-coated Cu and Ag-coated CuNi are also acceptable. Silver is a preferred metal material because it has high conductivity and exhibits minimal change in conductivity even in high-temperature, high-humidity environments.

[0060] The conductive material preferably has a spherical, dendritic, or flat shape. The term "flat shape" as used herein includes an elliptical shape formed by a curved shape combining an arc portion with a large radius of curvature and an arc portion with a small radius of curvature, and an oval shape formed by combining an arc portion and a flat portion. A perfect circle may also be included. There are no restrictions on the particle size, but a size of 0.1 μm to 30 μm is preferred.

[0061] (Polyester resin) The polyester resin is used to further improve the adhesion between the terminal electrode and the battery body. As used herein, the term "polyester resin" refers to a resin obtained by polycondensation of a polybasic acid and a polyhydric alcohol, and having an ester bond therein. A preferred example of the polybasic acid is a polycarboxylic acid (e.g., a dicarboxylic acid). A preferred example of the polyhydric alcohol is a polyalcohol (e.g., a diol).

[0062] In this embodiment, the terminal electrodes 151, 152 contain polyester resin, which allows the terminal electrodes 151, 152 to be firmly adhered to the battery body 140. Furthermore, the terminal electrodes 151, 152 of the solid-state battery 100 can follow the volume expansion of the battery body 140 that occurs when the solid-state battery is charged, thereby preventing cracks from occurring in the terminal electrodes 151, 152. The prevention of cracks from occurring in the terminal electrodes 151, 152 will be described in detail when explaining the "elongation at break" and "Young's modulus" in the examples described later.

[0063] 3. Insulating outer layer The solid-state battery of the present disclosure may include an insulating outer layer 160 as an additional configuration. Specifically, the insulating outer layer 160 may be provided on the outside of the battery body 140. The insulating outer layer 160 may generally be formed on the outermost surface of the battery body 140 to electrically, physically, and / or chemically protect the battery body 140. In particular, the insulating outer layer 160 may include an insulating outer layer 160 on the top surface side of the solid-state battery 100 and an insulating outer layer 160 on the bottom surface side. The insulating outer layer 160 may also be provided on the side of the battery body 140 on which the terminal electrodes 151 and 152 are not provided (the side of the battery body 140 perpendicular to the plane of the paper in FIG. 1). The material constituting the insulating outer layer preferably has excellent insulation properties, durability, and / or moisture resistance, and is environmentally safe, and may include, for example, a resin material, a glass material, and / or a ceramic material. Furthermore, the insulating outer layer may have the form of a fired body because it is manufactured by integral firing. Alternatively, the insulating outer layer 160 may not be provided and the device may be enclosed in a resin or ceramic package.

[0064] 4.Coating insulation film The solid-state battery of the present disclosure may include an insulating coating film 200 as an additional configuration. The insulating coating film 200 may be provided so as to cover the terminal electrodes 151, 152 and the battery body 140 (see FIG. 3). The insulating coating film 200 preferably corresponds to a resin. In other words, the insulating coating film 200 preferably includes a resin material. As can be seen from the embodiment shown in FIG. 3, this means that the battery body 140 provided on the support substrate 400 is sealed with the resin material of the insulating coating film 200. The insulating coating film 200 made of such a resin material, in combination with the inorganic film 300 described below, effectively contributes to reducing moisture penetration.

[0065] The insulating coating material may be any material that exhibits insulating properties. For example, if the insulating coating material contains a resin, the resin may be either a thermosetting resin or a thermoplastic resin. Specific examples of the resin material for the insulating coating material include, but are not limited to, epoxy resins, silicone resins, and / or liquid crystal polymers. By way of example only, the thickness of the insulating coating material may be 30 μm or more and 1000 μm or less, for example, 50 μm or more and 300 μm or less.

[0066] In addition, the insulating coating film is not essential for the solid-state battery, and a solid-state battery that does not have the insulating coating film may also be considered.

[0067] 5. Inorganic membrane As an additional configuration of the solid-state battery of the present disclosure, an inorganic film 300 may be provided to cover the insulating film 200. As shown in Fig. 3 , the inorganic film 300 is positioned on the insulating film 200, and therefore, together with the insulating film 200, has a form that largely envelops the battery element 140 on the support substrate 400 as a whole.

[0068] The inorganic film 300 preferably has a thin film form. The material of the inorganic film is not particularly limited as long as it contributes to the formation of an inorganic film having a thin film form, and may be metal, glass, oxide ceramics, or a mixture thereof. In a preferred embodiment, the inorganic film may contain a metal component. That is, the inorganic film may preferably be a metal thin film. By way of example only, the thickness of such an inorganic film may be 0.1 μm or more and 100 μm or less, for example, 1 μm or more and 50 μm or less.

[0069] In particular, depending on the manufacturing method, the inorganic film 300 may be a dry-plated film. Such a dry-plated film is obtained by a vapor-phase method such as physical vapor deposition (PVD) or chemical vapor deposition (CVD), and has an extremely small thickness on the order of nanometers or microns. Such a thin dry-plated film contributes to more compact packaging.

[0070] The dry-plated film may be composed of, for example, at least one metal component or semimetal component selected from the group consisting of aluminum (Al), nickel (Ni), palladium (Pd), silver (Ag), tin (Sn), gold (Au), copper (Cu), titanium (Ti), platinum (Pt), silicon (Si), and stainless steel, an inorganic oxide, and / or a glass component. Dry-plated films composed of such components are chemically and / or thermally stable, and therefore may result in solid-state batteries with excellent chemical resistance, weather resistance, and / or heat resistance, and improved long-term reliability.

[0071] In addition, an inorganic film is not necessarily essential for a solid-state battery, and a solid-state battery without an inorganic film is also conceivable.

[0072] 6. Support substrate The solid-state battery of the present disclosure may include a support substrate 400 as an additional component. The support substrate 400 is a substrate provided to support the battery element 140. The support substrate is positioned on one side of the main surface of the solid-state battery to provide support. As a "substrate," the support substrate preferably has a thin plate-like shape overall.

[0073] The support substrate 400 may be, for example, a resin substrate or a ceramic substrate, with a water-resistant substrate being preferable. In a preferred embodiment, the support substrate 400 may be a ceramic substrate. That is, the support substrate 400 may contain ceramic, which may constitute the base material of the substrate. A support substrate made of ceramic contributes to preventing water vapor transmission and is also preferable in terms of heat resistance during substrate mounting. Such a ceramic substrate can be obtained through firing, for example, by firing a green sheet laminate. In this regard, the ceramic substrate may be, for example, an LTCC substrate (Low Temperature Co-fired Ceramics) or an HTCC substrate (High Temperature Co-fired Ceramics). By way of example only, the thickness of the support substrate may be 20 μm or more and 1000 μm or less, for example, 100 μm or more and 300 μm or less.

[0074] The support substrate 400 may also function as a terminal substrate for the battery element 140. That is, a packaged solid-state battery with a substrate interposed therebetween may be mounted on another secondary substrate such as a printed wiring board. For example, the solid-state battery may be surface-mounted via the support substrate through solder reflow or the like. For this reason, the packaged solid-state battery may be an SMD-type battery. In particular, when the terminal substrate is made of a ceramic substrate, the solid-state battery may be an SMD-type battery that has high heat resistance and can be solder-mounted.

[0075] Since it is a terminal substrate, it preferably has wiring, and in particular, it preferably has wiring 410 (see FIG. 3) that electrically connects the upper and lower surfaces or the upper and lower surface layers. That is, a preferred embodiment of the support substrate has wiring that electrically connects the upper and lower surfaces of the substrate, and may be a terminal substrate for the external terminals of a packaged solid-state battery.

[0076] The wiring 410 in the terminal substrate is not particularly limited and may have any form as long as it contributes to electrical connection between the upper and lower surfaces of the substrate. Because it contributes to electrical connection, the wiring 410 in the terminal substrate can also be considered a conductive portion of the substrate. Such a conductive portion of the substrate may have the form of a wiring layer, a via, and / or a land. For example, in the embodiment shown in FIG. 3, vias 412 and / or lands 411 are provided in the support substrate 400. The term "via" here refers to a member for electrically connecting the support substrate in the vertical direction, i.e., the thickness direction of the substrate. For example, a filled via is preferred, and it may also take the form of an inner via. Furthermore, the term "land" in this specification refers to a terminal portion / connection portion for electrical connection (preferably a terminal portion / connection portion connected to a via) provided on the upper and / or lower main surface of the support substrate. For example, it may be a square land or a round land.

[0077] [Electronic device configuration] The electronic device of the present disclosure is one in which the above-described solid-state battery is surface-mounted. Specifically, the wiring of the support substrate 400 enables the surface mounting of the solid-state battery. In this specification, "surface mounting" refers to a technique in which a solid-state battery is directly fixed to a pattern formed on a substrate. As an example, the above-described solid-state battery 1 may be mounted on a printed circuit board or the like and packaged. Furthermore, electronic components other than the solid-state battery may be mounted on the electronic device.

[0078] [Solid-state battery manufacturing method] The solid-state battery of the present disclosure is manufactured through processes including (1) preparation of a battery element, (2) preparation of a terminal electrode material, (3) firing of the battery element, (4) application of the terminal electrode material, (5) curing of the terminal electrode material, (6) fixing to a support substrate, and (7) formation of a covering insulating film and an inorganic film. These processes are explained in order below.

[0079] (1) Preparation of the battery element When manufacturing the battery element, a sheet containing a solid electrolyte, a positive electrode paste, and a negative electrode paste are prepared.

[0080] The sheet containing the solid electrolyte is formed by mixing the solid electrolyte, an organic binder, a solvent, and any additives to prepare a slurry, and then firing the prepared slurry to form a sheet.

[0081] The positive electrode paste is prepared by mixing a positive electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and any additives.Similarly, the negative electrode paste is prepared by mixing a negative electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and any additives.

[0082] First, a positive electrode paste is printed on a sheet containing a solid electrolyte, and a current collecting layer and / or a negative layer is printed as needed. Similarly, a negative electrode paste is printed on the sheet, and a current collecting layer and / or a negative layer is printed as needed. These sheets printed with the positive electrode paste and sheets printed with the negative electrode paste are alternately stacked to obtain a laminate. Note that the outermost layer (top layer and / or bottom layer) of the laminate may be an electrolyte layer, an insulating layer, or an electrode layer.

[0083] (2) Preparation of terminal electrode material First, a terminal electrode material (e.g., conductive paste) for the terminal electrodes 151 and 152 is prepared. Ag and polyester resin are prepared as the conductive material. The Ag particles may have any shape, but preferably have a flat shape. The Ag particle size may be any size, but is preferably 0.1 μm to 30 μm, and more preferably 0.5 μm to 20 μm. In this specification, the term "particle size" refers to the median diameter (D50) at which the cumulative volume is 50% in a volume-based particle size distribution. The median diameter (D50) is measured, for example, using image analysis or a laser diffraction / scattering particle distribution measurement device, but is not limited to such devices.

[0084] The conductive material and polyester resin are then mixed together. The conductive material and polyester resin are mixed in a volume ratio ranging from 20 / 80 to 60 / 40. A volume ratio ranging from 30 / 70 to 50 / 50 is particularly suitable, as it provides a good balance of various properties. The terminal electrode material may further contain additional components such as a resin and a solvent. The term "terminal electrode material" as used herein refers to a material capable of forming a flow in the hydrodynamic sense or a material capable of maintaining such a flow. Examples of such materials include liquids such as pastes, solutions, and suspensions.

[0085] The solvent dissolves the resin binder, and may be, for example, an organic solvent. The organic solvent is not particularly limited, and examples thereof include alcohols including methanol, ethanol, 1-propanol, 2-propanol, hexanol, and cyclohexanol, glycols including ethylene glycol and propylene glycol, ketones including methyl ethyl ketone, diethyl ketone, and methyl isobutyl ketone, terpenes including α-terpineol, β-terpineol, and γ-terpineol, ethylene glycol monoalkyl ethers, ethylene glycol dialkyl ethers, diethylene glycol monoalkyl ethers, diethylene glycol dialkyl ethers, ethylene glycol monoalkyl ether acetates, ethylene glycol dialkyl ether acetates, diethylene glycol monoalkyl ether acetates, diethylene glycol dialkyl ether acetates, propylene glycol monoalkyl ethers, propylene glycol dialkyl ethers, propylene glycol monoalkyl ether acetates, propylene glycol dialkyl ether acetates, and monoalkyl cellosolves. Alternatively, a mixture of at least one solvent selected from these solvents or two or more solvents may be used alone. As an example of the organic solvent, an alcohol-based solvent such as terpineol is preferably used. A dispersing agent may be added to the solvent.

[0086] After the terminal electrode material is prepared, the terminal electrode material is applied to the exposed positive electrode side and the exposed negative electrode side of the battery body.

[0087] (3) Firing of the battery element The firing of the battery element is carried out by heating in an oxygen-containing nitrogen gas atmosphere or in air at a desired firing temperature (for example, a firing peak temperature in the range of 300°C to 600°C), which is merely an example. The firing may be carried out while applying pressure to the battery element precursor in the stacking direction (and in some cases in the stacking direction and a direction perpendicular to the stacking direction).

[0088] (4) Applying terminal electrode material After the terminal electrode material is prepared, the terminal electrode material is applied to the exposed positive electrode side and the exposed negative electrode side of the battery body.

[0089] (5) Hardening of terminal electrode material The battery element coated on the positive electrode exposed side surface and the negative electrode exposed side surface is cured at a desired curing temperature (for example, in the range of 100°C to 300°C).

[0090] (6) Fixing to a supporting substrate The support substrate has vias and / or lands to allow surface mounting to a secondary substrate. For example, it can be obtained by stacking and firing multiple green sheets. This is especially true when the support substrate is a ceramic substrate. The support substrate can be prepared, for example, in accordance with the preparation of an LTCC substrate.

[0091] The vias and / or lands in the support substrate are manufactured by, for example, forming holes (diameter size: approximately 50 μm or more and 200 μm or less) using a punch press or a carbon dioxide laser, and filling the holes with a conductive paste material, or by using a printing method.

[0092] After the support substrate is manufactured, it is arranged so that the conductive portion of the support substrate and the terminal electrode of the battery element are electrically connected to each other. Then, a conductive paste may be applied to the support substrate, thereby electrically connecting the conductive portion of the support substrate and the terminal electrode to each other. As the conductive paste, in addition to Ag conductive paste, a nanopaste, an alloy paste, a brazing material, or other conductive paste that does not require washing with flux or the like after formation can be used.

[0093] (7) Formation of insulating and inorganic coating films Next, a covering insulating film is formed so as to cover the battery element on the support substrate. Therefore, raw materials for the covering insulating film are provided so as to completely cover the battery element on the support substrate. When the covering insulating film is made of a resin material, a resin precursor is provided on the support substrate and cured to form the covering insulating film.

[0094] In a preferred embodiment, the insulating coating film may be molded by applying pressure in a mold. By way of example only, the insulating coating film that seals the battery element on the support substrate may be molded using a compression mold. If the insulating coating film is made of a resin material typically used in molding, the raw material may be granular or thermoplastic. Such molding is not limited to mold molding, and may also be performed through polishing, laser processing, and / or chemical treatment.

[0095] Next, an inorganic film is formed. The inorganic film may be formed by, for example, dry plating, to form a dry-plated film. More specifically, dry plating is performed to form an inorganic film on the exposed surface other than the bottom surface of the coating precursor (i.e., other than the bottom surface of the support substrate). In a preferred embodiment, sputtering is performed to form a sputtered film on the exposed outer surface other than the bottom surface of the coating precursor.

[0096] By going through the steps described above, the solid state battery of the present disclosure can finally be obtained. [Example]

[0097] [Evaluation 1: Evaluation of terminal electrode paste] The conductive pastes of Examples 1 to 4 and Comparative Examples 1 to 4 shown in Table 1 below were evaluated for their breaking elongation and Young's modulus. The conductive material used was flat Ag powder, and the resins used were polyester resins A to D, each with a different molecular structure and molecular weight. The breaking elongation and Young's modulus were evaluated as follows: An appropriate amount of conductive paste was dropped onto a glass plate, and a paste coating film was applied using an applicator. The applied coating film was placed in a hot air circulating oven and heated and cured under the standard curing conditions for each paste. The cured coating film was punched into a dumbbell shape using a Thomson blade and used for measurement.

[0098] The prepared samples were tested using a dynamic mechanical analysis (DMA) measuring device (TA Instruments RSA-G2) at a test speed of 3 mm / min. The dimensions at break after the tensile test were measured from the initial dimensions (13 mm) before the tensile test. The "breaking elongation" was calculated from the obtained initial dimensions and dimensions after break. The breaking elongation was measured and calculated for five samples, and the average value was used.

[0099] The Young's modulus was measured by a load-unloading test using an ultra-microindentation hardness tester (ENT-1100a manufactured by Elionix). More specifically, a Berkovich indenter was used as the indenter, and the Young's modulus was measured by analyzing the displacement curve when the test was performed with an indentation load of 50 mN. The breaking elongation was measured and calculated for three samples prepared for each example and comparative example, and the average value was used.

[0100] [Table 1]

[0101] According to the results in Table 1, Examples 1 to 4 had elongation rates at break in the range of 0.8% or more and 50% or less. On the other hand, Comparative Examples 1 and 2 had elongation rates at break of less than 0.8%, and Comparative Example 3 had an elongation rate at break of more than 50%.

[0102] If the breaking elongation rate is 0.8% or more, it can follow the volume expansion of the battery body that occurs when the solid-state battery is charged, thereby reducing the occurrence of cracks in the terminal electrode. On the other hand, if the breaking elongation rate is less than 0.8%, it cannot follow the volume expansion of the battery body of the rechargeable battery, and cracks in the terminal electrode were occasionally observed. Furthermore, if the breaking elongation rate exceeds 50%, as in Comparative Example 3, the adhesion between the battery body and the terminal electrode weakens, and peeling between the battery body and the terminal electrode was occasionally observed. In consideration of the above, the breaking elongation rate of the terminal electrode of the present disclosure is preferably 0.8% or more and 50% or less.

[0103] Furthermore, according to the results in Table 1, the Young's modulus of Examples 1 to 4 falls within the range of 2.0 GPa or more and 6.0 GPa or less. On the other hand, the Young's modulus of Comparative Examples 1 and 2 is 6.0 GPa or more, and the Young's modulus of Comparative Example 3 is less than 2.0 GPa.

[0104] As shown in the above results, if the Young's modulus is 2.0 GPa or more, it can follow the volume expansion of the battery body that occurs when charging a solid-state battery, thereby reducing the occurrence of cracks in the terminal electrodes. On the other hand, if the Young's modulus is less than 2.0 GPa, it cannot follow the volume expansion of the battery body of the rechargeable battery, and cracks in the terminal electrodes were occasionally observed. Furthermore, if the Young's modulus was 0.5 GPa or less, as in Comparative Example 3, the adhesion between the battery body and the terminal electrodes was weak, and peeling between the battery body and the terminal electrodes was occasionally observed. In consideration of the above, the Young's modulus of the terminal electrodes of the present disclosure is preferably 2.0 GPa or more and 6.0 GPa or less.

[0105] [Evaluation 2: Evaluation of electrical characteristics of solid-state batteries] The electrical characteristics of the solid state batteries of Examples 1 to 4 and Comparative Examples 1 to 3 were evaluated below. The results are shown in Table 2.

[0106] [Table 2]

[0107] The evaluation test consisted of measuring the charge / discharge characteristics of the solid-state battery and evaluating the voltage fluctuation during discharge. In addition, the alternating current impedance (ACimp) was calculated and evaluated after the cycle test of the solid-state battery.

[0108] The charge-discharge and cycle tests of the solid-state battery were performed using a charge-discharge evaluation device, TOSCAT-3100, manufactured by Toyo Systems Co., Ltd. The solid-state battery was charged and discharged for 100 cycles at 60°C. The charge-discharge conditions were as follows: charging at a constant current of 0.5 C (the current required for full charge in 2 hours) until the voltage reached 4.1 V, followed by constant voltage charging at 4.1 V at a current of 0.01 C (the current required for full charge in 100 hours). Discharging at a constant current of 0.1 C (the current required for full discharge in 10 hours) until the voltage reached 2.0 V.

[0109] The voltage fluctuation during discharge was confirmed by checking whether a voltage increase of 0.05 V or more occurred from the baseline of the discharge curve during discharge. The ACimp after 100 charge / discharge cycles was evaluated by measuring the resistance value of the solid-state battery after the cycle test using the AC impedance method. After the cycle test, the Cole-Cole plot of the solid-state battery was measured from 1 MHz to 1 Hz (device: Solartron Instruments Impedance Gain / Phase Analyzer SI1260), and the end point of the first arc was defined as ACimp. The smaller the ACimp value, the better the battery's input / output characteristics. An ACimp value of 70 Ω or less after 100 cycles was considered to be good.

[0110] According to the evaluation of AC impedance shown in Table 2, in Comparative Examples 1 and 2 (which used epoxy resin), the voltage increase during discharge was 0.05 V or more. On the other hand, in Examples 1 to 4, the voltage increase during discharge was kept to less than 0.05 V, and good discharge characteristics were obtained.

[0111] In addition, in Comparative Example 3 (using silicone resin), although the voltage increase during discharge was suppressed, the AC impedance value was 129 Ω, which was higher than the reference AC impedance value (70 Ω).On the other hand, in Examples 1 to 4, the AC impedance values ​​were all below 70 Ω, and therefore good AC impedance characteristics were obtained.

[0112] It should be noted that the embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present disclosure should not be interpreted solely by the above-described embodiments, but should be defined based on the claims. The technical scope of the present disclosure also includes all modifications within the meaning and scope of the claims. For example, the solid-state battery is not limited to a substantially hexahedral shape, but may also be a polyhedral, cylindrical, or spherical shape. [Industrial Applicability]

[0113] The packaged solid-state batteries of the present disclosure can be used in a variety of fields where battery use or storage is envisioned. By way of example only, the packaged solid-state batteries of the present disclosure can be used in electronic packaging. The present disclosure can also be used in the electrical, information, and communications fields where mobile devices and the like are used (for example, the electrical and electronic equipment fields or mobile device fields including small electronic devices such as mobile phones, smartphones, laptops and digital cameras, activity monitors, arm computers, electronic paper, RFID tags, card-type electronic money, and smart watches), home and small industrial applications (for example, power tools, golf carts, and home, nursing care, and industrial robots), large industrial applications (for example, forklifts, elevators, and port cranes), transportation systems (for example, hybrid cars, electric cars, buses, trains, electrically assisted bicycles, and electric motorcycles), power system applications (for example, various types of power generation, road conditioners, smart grids, and general home-installed energy storage systems), medical applications (for medical devices such as earphones and hearing aids), pharmaceutical applications (for example, medication management systems), the IoT field, and space and deep-sea applications (for example, space probes, submersible research vessels, and the like). [Explanation of symbols]

[0114] 100 solid state battery 110 Positive electrode layer 111 Positive electrode active material layer 112 Positive electrode current collector layer 120 negative electrode layer 121 Negative electrode active material layer 122 Negative electrode current collector layer 130 Solid electrolyte layer 140 Battery element 151 Positive electrode layer side terminal electrode 152 Negative layer side terminal electrode 160 Insulating outer layer 200 Coated insulation film 300 Inorganic membrane 400 Support substrate 410 Wiring 411 rand 412 Beer

Claims

1. a battery element having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer interposed between the positive electrode layer and the negative electrode layer; a terminal electrode provided on an end surface of the battery body and electrically connected to the battery body, the terminal electrode includes a conductive material and a polyester-based resin, The solid-state battery, wherein the terminal electrode has a Young's modulus of 2.0 GPa or more and 6.0 GPa or less.

2. The solid-state battery according to claim 1 , wherein the conductive material has a flat shape.

3. The solid-state battery of claim 1 , wherein the conductive material is silver.

4. The solid-state battery according to claim 1 , wherein the terminal electrode has a breaking elongation of 0.8% or more and 50% or less.

5. the solid electrolyte layer comprises an oxide glass and / or an oxide glass ceramic; 2. The solid-state battery according to claim 1, wherein the oxide glass and / or the oxide glass ceramic contains at least one element selected from the group consisting of lithium, silicon, and boron.

6. the solid electrolyte layer comprises an oxide glass and / or an oxide glass ceramic; The oxide glass and / or the oxide glass ceramic is Lithium oxide, and at least one selected from the group consisting of germanium oxide, silicon oxide, boron oxide, and phosphorus oxide, The solid-state battery according to claim 1 .

7. 2. The solid-state battery according to claim 1, wherein the terminal electrode is provided on a side surface of the battery body that is positioned in a direction intersecting a direction in which the positive electrode layer and the negative electrode layer are stacked.

8. The solid-state battery according to claim 7 , wherein the terminal electrode extends from a side surface of the battery body to a bottom surface of the battery body.

9. The solid-state battery according to claim 7 , wherein the terminal electrodes extend from the side surfaces of the battery body to the top and bottom surfaces of the battery body.

10. The solid-state battery according to claim 1 , wherein the terminal electrode is electrically connected to a supporting substrate.

11. The solid-state battery according to claim 1 , wherein the terminal electrodes and the battery body are covered with an insulating coating.

12. The solid-state battery according to claim 11 , wherein the insulating coating film is coated with an inorganic film.

13. The solid-state battery of claim 1 , wherein the solid-state battery is packaged for surface mounting.

14. The solid-state battery according to claim 1 , wherein the battery element is made of a sintered body.

15. The solid-state battery according to claim 1 , wherein the positive electrode layer and the negative electrode layer are layers capable of absorbing and releasing lithium ions.

16. An electronic device having the solid-state battery according to any one of claims 1 to 15 surface-mounted thereon.

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