Solid-state battery package and manufacturing method therefor

Abstract

Provided is a solid-state battery package comprising a substrate, a solid-state battery that is provided on the substrate, an insulating layer that covers the solid-state battery so as to be in contact with the solid-state battery, and a metal exterior body that covers the insulating layer so as to be in contact with the insulating layer and that is joined to the substrate, wherein the metal exterior body has a groove portion.

Description

Solid-state battery package and method of manufacturing same

[0001] The present disclosure relates to solid-state battery packages, particularly solid-state batteries packaged to be conducive to substrate mounting, and methods for manufacturing the same.

[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 laptop computers.

[0003] In secondary batteries, a liquid electrolyte is generally used as a medium for ion migration that 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 a solid electrolyte instead of an electrolytic solution. Patent Document 1 discloses an embodiment of such a solid-state battery that includes a battery element and an exterior body that houses the battery element and has an internal space.

[0005] JP 2010-118159 A

[0006] The present inventors have found that there are issues that need to be improved in conventional solid-state batteries. Specifically, when the exterior body has an internal space, the battery energy density may decrease. Furthermore, when the battery is charged and discharged, the battery elements expand and contract. If stress caused by this expansion and contraction is concentrated at a specific location of the battery components, the battery components may be damaged.

[0007] Therefore, an object of the present disclosure is to provide a solid-state battery package that can improve the battery energy density and alleviate stress that occurs during battery charging and discharging.

[0008] In order to achieve the above object, the present disclosure provides a solid-state battery package including: a substrate; a solid-state battery provided on the substrate; an insulating layer covering the solid-state battery so as to be in contact with the solid-state battery; and a metal exterior body covering the insulating layer so as to be in contact with the insulating layer and joined to the substrate, wherein the metal exterior body has a groove portion.

[0009] In order to achieve the above object, the present disclosure provides a method for manufacturing a solid-state battery package, including the steps of: preparing a substrate; mounting a solid-state battery on the substrate; covering the solid-state battery with an insulating layer so as to be in contact with the solid-state battery; and providing a metal exterior body that is bonded to the substrate, covers the insulating layer so as to be in contact with the insulating layer, and has a groove.

[0010] The solid-state battery package of the present disclosure can improve the battery energy density and alleviate stress that occurs during battery charge and discharge.

[0011] FIG. 1 is a perspective view schematically illustrating the configuration of a packaged solid-state battery (solid-state battery package) according to the first embodiment of the present disclosure. FIG. 2 is a cross-sectional view (cross-sectional view taken along the line A-A in FIG. 1 ) schematically illustrating the configuration of a solid-state battery package according to an embodiment of the present disclosure. FIG. 3 is an enlarged cross-sectional view schematically illustrating the configuration of a corner portion (circled portion) of the metal exterior body shown in FIG. 2. FIG. 4 is a cross-sectional view schematically illustrating the configuration of a solid-state battery package according to a second embodiment of the present disclosure. FIG. 5 is a cross-sectional view schematically illustrating the configuration of a solid-state battery package according to a third embodiment of the present disclosure. FIG. 6 is a cross-sectional view schematically illustrating the configuration of a solid-state battery package according to a fourth embodiment of the present disclosure. FIG. 7A is a process diagram schematically illustrating step 1 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. FIG. 7B is a process diagram schematically illustrating step 2 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. FIG. 7C is a process diagram schematically illustrating step 3 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. FIG. 7D is a process diagram schematically illustrating step 4 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. FIG. 7E is a process diagram schematically illustrating step 5 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure.

[0012] Hereinafter, a solid-state battery package according to one aspect of the present disclosure will be described in detail with reference to the drawings as necessary. The drawings include schematic illustrations in part to facilitate understanding of the present disclosure, and may not reflect actual dimensions or proportions.

[0013] [Solid-State Battery Package] The term "cross-sectional view" used in this specification is based on the shape of the solid-state battery package as seen from a direction perpendicular to the main surface of the substrate.

[0014] The "upper and lower directions" and "lower and upper directions" used directly or indirectly in this specification correspond to the upper and lower directions and the left and right directions in the drawings, respectively. Unless otherwise specified, the same symbols or signs indicate the same members, parts, or the same meanings. In a preferred embodiment, the vertically downward direction (i.e., the direction in which gravity acts) can be considered to correspond to the "lower direction" / "bottom side (lower surface side)," and the opposite direction can be considered to correspond to the "upper direction" / "top side (upper surface side, top surface side)."

[0015] Furthermore, in this specification, "on" a substrate, layer, etc., includes not only cases where it is in contact with the upper surface of the substrate, layer, etc., but also cases where it is not in contact with the upper surface of the substrate, layer, etc. In other words, "on" a substrate, layer, etc., includes cases where a new film or layer is formed above the substrate or layer, and / or cases where another film or layer is interposed between the substrate or layer. Furthermore, "on" does not necessarily mean the upper side in the vertical direction. "On" merely indicates the relative positional relationship of the substrate, layer, etc.

[0016] <First embodiment> Fig. 1 is a perspective view schematically showing the configuration of a packaged solid-state battery (solid-state battery package) according to a first embodiment of the present disclosure. Fig. 2 is a cross-sectional view (cross-sectional view taken along A-A in Fig. 1) schematically showing the configuration of a solid-state battery package according to an embodiment of the present disclosure. Fig. 3 is an enlarged cross-sectional view schematically showing the configuration of a corner portion (circled portion) of the metal exterior body in Fig. 2.

[0017] As shown in FIGS. 1 to 3 , the solid-state battery package 1000 according to the first embodiment mainly includes the following components: a substrate 200; a solid-state battery 100 provided on the substrate 200 and having end electrodes 120 on its end faces; an insulating layer 300 covering the solid-state battery 100 with the end electrodes 120; and a metal exterior body 400 covering the insulating layer 300 and joined to the substrate 200.

[0018] In this specification, the term "solid-state battery package" refers to a packaged solid-state battery, and in a broad sense, refers to a solid-state battery device configured to protect the solid-state battery from the external environment, and in a narrow sense, refers to a solid-state battery device that includes a mountable substrate and protects the solid-state battery from the external environment.

[0019] In the following, first, the basic configuration of the solid-state battery package 1000 will be described, followed by a description of the characteristic features of the first embodiment.

[0020] <Basic Configuration of Solid-State Battery> First, a description will be given of the basic configuration of the solid-state battery package 1000. Specifically, each component of the solid-state battery package 1000 will be described.

[0021] The solid-state battery 100 is a stacked-type solid-state battery configured such that each layer constituting a battery unit is stacked on top of another, and each such layer is preferably made of a fired body. The solid-state battery 100 includes a substantially rectangular solid-state battery stack 110 and two opposing end electrodes 120 disposed on end surfaces of the solid-state battery stack 110. The solid-state battery stack 110 is configured by alternately stacking multiple positive electrode layers 112 and negative electrode layers 114 with solid electrolyte layers 116 interposed therebetween. The positive electrode layer 112, which serves as an electrode layer, is electrically connected to one of the two terminal electrodes 120. The negative electrode layer 114, which serves as an electrode layer, is electrically connected to the other of the two terminal electrodes 120. The solid-state battery 100 is disposed on a substrate 200 such that the stacking direction of the positive electrode layer 112 and the negative electrode layer 114 coincides with the mounting direction of the solid-state battery 100 on the substrate 200.

[0022] In this specification, the term "solid-state battery" refers in a broad sense to a battery whose components are made of solids, and in a narrow sense to an all-solid-state battery whose components (particularly preferably all components) are made of solids. Examples of the solid-state battery 100 include so-called secondary batteries (more specifically, storage batteries) that can be repeatedly charged and discharged, and primary batteries that can only be discharged.

[0023] (Electrode Layers: Positive Electrode Layer and Negative Electrode Layer) The positive electrode layer 112 contains at least a positive electrode active material, and may further contain at least one selected from the group consisting of a solid electrolyte, a conductive material, and a sintering aid, and may further include a positive electrode current collecting layer. The negative electrode layer 114 contains at least a negative electrode active material, and may further contain at least one selected from the group consisting of a solid electrolyte, a conductive material, and a sintering aid, and may further include a negative electrode current collecting layer. The material constituting the negative electrode layer 114 may be the same as the material constituting the positive electrode layer 112.

[0024] - Active Material - The active materials (positive electrode active material and negative electrode active material) are materials involved in the transfer of electrons in the solid-state battery 100. Carriers (ions, particularly lithium ions or sodium ions) move (conduct) between the positive electrode layer 112 and the negative electrode layer 114 via the solid electrolyte, transferring electrons to charge and discharge the battery. It is preferable that each of the electrode layers, the positive electrode layer 112 and the negative electrode layer 114, is a layer capable of absorbing and releasing lithium ions or sodium ions, in particular. In other words, it is preferable that the solid-state battery 100 is an all-solid-state secondary battery in which lithium ions or sodium ions move between the positive electrode layer 112 and the negative electrode layer 114 via the solid electrolyte layer 116 to charge and discharge the battery.

[0025] = Positive Electrode Active Material = Positive electrode active materials capable of absorbing and releasing lithium ions include, for example, at least one selected from the group consisting of lithium-containing phosphate compounds having a Nasicon structure, lithium-containing phosphate compounds having an olivine structure, lithium-containing layered oxides, and lithium-containing oxides having a spinel structure. An example of a lithium-containing phosphate compound having a Nasicon structure is Li3V2(PO4)3. An example of a lithium-containing phosphate compound having an olivine structure is Li3Fe2(PO4)3, LiFePO4, and / or LiMnPO4. An example of a lithium-containing layered oxide is LiCoO2 and / or LiCo 1 / 3 Ni 1 / 3 Mn 1 / 3 Examples of lithium-containing oxides having a spinel structure include LiMnO and / or LiNi.0.5 Mn 1.5 O4, etc. Examples of lithium compounds include, but are not limited to, lithium transition metal composite oxides and lithium transition metal phosphate compounds. Lithium transition metal composite oxides are oxides containing lithium and one or more transition metal elements as constituent elements. Lithium transition metal phosphate compounds are phosphate compounds containing lithium and one or more transition metal elements as constituent elements. The type of transition metal element is not particularly limited, but examples include cobalt (Co), nickel (Ni), manganese (Mn), and iron (Fe).

[0026] In addition, as the positive electrode active material capable of absorbing and releasing sodium ions, for example, 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 can be mentioned. ３ V ２ (P.O. ４ ) ３ , NaCoFe ２ (P.O. ４ ) ３ , Na ２ Ni ２ Fe(PO ４ ) ３ , Na ３ Fe ２ (P.O. ４ ) ３ , Na ２ FeP ２ O ７ and Na ４ Fe ３ (P.O. ４ ) ２ (P ２ O ７ ) and NaFeO as a sodium-containing layered oxide ２ At least one selected from the group consisting of:

[0027] Other examples of the positive electrode active material include oxides, disulfides, and conductive polymers. Examples of oxides include titanium oxide, vanadium oxide, and manganese dioxide. Examples of disulfides include titanium disulfide and molybdenum sulfide. Examples of chalcogenides include niobium selenide. Examples of conductive polymers include disulfides, polypyrrole, polyaniline, polythiophene, polyparastyrene, polyacetylene, and polyacene.

[0028] =Negative Electrode Active Material= Examples of negative electrode active materials capable of absorbing and releasing lithium ions include at least one selected from the group consisting of oxides containing at least one element selected from the group consisting of titanium (Ti), silicon (Si), tin (Sn), chromium (Cr), iron (Fe), niobium (Nb), and molybdenum (Mo), carbon materials such as graphite, graphite-lithium compounds, lithium alloys, lithium-containing phosphate compounds having a Nasicon structure, lithium-containing phosphate compounds having an olivine structure, and lithium-containing oxides having a spinel structure. An example of a lithium alloy is Li-Al. An example of a lithium-containing phosphate compound having a Nasicon structure is Li3V2(PO4)3 and / or LiTi2(PO4)3. An example of a lithium-containing phosphate compound having an olivine structure is Li3Fe2(PO4)3 and / or LiCuPO4. An example of a lithium-containing oxide having a spinel structure is Li4Ti5O. 12 etc.

[0029] In addition, examples of negative electrode active materials capable of absorbing and releasing sodium ions include 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.

[0030] -Conductive Material- Examples of the conductive material include at least one conductive material selected from the group consisting of metal materials such as silver, palladium, gold, platinum, aluminum, copper, and nickel, and carbon.

[0031] -Sintering Aid- Examples of the sintering aid include at least one selected from the group consisting of lithium oxide, sodium oxide, potassium oxide, boron oxide, silicon oxide, bismuth oxide, and phosphorus oxide.

[0032] Current Collector Layers—The current collector layers (positive electrode current collector layer and negative electrode current collector layer) may each have the form of a foil. Here, if emphasis is placed on improving electronic conductivity through co-firing, reducing the manufacturing cost of the solid-state battery 100, and / or reducing the internal resistance of the solid-state battery 100, the current collector layers may have the form of a sintered body. The positive electrode current collector constituting the positive electrode current collector layer and the negative electrode current collector constituting the negative electrode current collector layer are preferably made of a conductive material with high conductivity. Examples of such conductive materials include at least one selected from the group consisting of silver, palladium, gold, platinum, aluminum, copper, and nickel. The current collectors (positive electrode current collector and negative electrode current collector) may have electrical connectors for electrical connection to the outside and may be configured to be electrically connectable to the end electrode 120. When the current collector layers have the form of a sintered body, they may be made of a sintered body containing a conductive material and a sintering aid. The conductive material contained in the current collecting layer may be selected from, for example, the same materials as the conductive materials that may be contained in the electrode layers (positive electrode layer 112 and negative electrode layer 114). The sintering aids contained in the positive electrode current collecting layer and the negative electrode current collecting layer may be selected from, for example, the same materials as the sintering aids that may be contained in the positive electrode layer 112 and the negative electrode layer 114, respectively.

[0033] The thickness of the positive electrode layer 112 and the negative electrode layer 114 is not particularly limited, but may be, for example, each independently from 2 μm to 200 μm, particularly from 5 μm to 100 μm.

[0034] (Solid Electrolyte Layer) The solid electrolyte layer 116 is interposed between the positive electrode layer 112 and the negative electrode layer 114 and is responsible for carrier conduction between these electrode layers. The solid electrolyte layer 116 may be present around the positive electrode layer 112 and / or the negative electrode layer 114 so as to protrude from between the positive electrode layer 112 and the negative electrode layer 114. The thickness of the solid electrolyte layer 116 is not particularly limited, but is, for example, 1 μm or more and 500 μm or less, particularly 1 μm or more and 200 μm or less. In this specification, the thickness of the solid electrolyte layer 116 refers to the thickness of the solid electrolyte layer 116 disposed between the positive electrode layer 112 and the negative electrode layer 114.

[0035] -Solid Electrolyte- The solid electrolyte layer 116 includes a solid electrolyte and may further include a sintering aid. The solid electrolyte is a material capable of conducting carriers (e.g., lithium ions or sodium ions). In particular, the solid electrolyte layer 116 constituting a battery structural unit in the solid-state battery 100 may form a layer capable of conducting lithium ions between the positive electrode layer 112 and the negative electrode layer 114. Examples of the solid electrolyte include at least one selected from the group consisting of crystalline solid electrolytes, glass-based solid electrolytes, and glass-ceramic-based solid electrolytes.

[0036] The solid electrolyte capable of conducting lithium ions will be described. Examples of the crystalline solid electrolyte include oxide-based crystalline materials and sulfide-based crystalline materials. Examples of the oxide-based crystalline materials include lithium-containing phosphate compounds having a Nasicon structure, oxides having a perovskite structure, oxides having a garnet structure or a garnet-like structure, and oxide glass ceramic-based lithium ion conductors. Examples of the lithium-containing phosphate compounds having a Nasicon structure include Li ｘ M ｙ (P.O. ４ ) 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 (P.O.４ ) ３ Examples of oxides having a perovskite structure include La ０．５５ Li ０．３５ TiO ３ Examples of oxides having a garnet-type or garnet-like structure include Li ７ La ３ Zr ２ O １２ etc.

[0037] In addition, sulfide-based crystal materials include thio-LISICON, for example, Li ３．２５ Ge ０．２５ P ０．７５ S ４ and Li １０ GeP ２ S １２ The crystalline solid electrolyte may include a polymer material (for example, polyethylene oxide (PEO)).

[0038] Examples of glass-based solid electrolytes include oxide-based glass materials and sulfide-based glass materials. Examples of oxide-based glass materials include 50Li ４ SiO ４ ・50Li ３ BO ３ Examples of sulfide-based glass materials include 30Li ２ S・26B ２ S ３ ・44LiI, 63Li ２ S・36SiS ２ ・1Li ３ P.O. ４ , 57Li ２ S・38SiS ２ ・5Li ４ SiO ４ , 70Li ２ S・30P ２ S ５ and 50Li ２ S・50GeS ２ Examples include:

[0039] Examples of glass ceramic solid electrolytes include oxide-based glass ceramic materials and sulfide-based glass ceramic materials. Examples of oxide-based glass ceramic materials include a phosphate compound containing lithium, aluminum, and titanium as constituent elements (LATP) and a phosphate compound containing lithium, aluminum, and germanium as constituent elements (LAGP). Examples of LATP include Li, １．０７ Al ０．６９ Ti １．４６ (P.O. ４ ) ３ Examples of LAGP include Li １．５ Al ０．５ Ge １．５ (P.O. ４ ) and the like. Examples of sulfide-based glass ceramic materials include Li ７ P ３ S １１ and Li ３．２５ P ０．９５ S ４ Examples include:

[0040] 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).

[0041] - Sintering Aid - The sintering aid contained in the solid electrolyte layer 116 may be, for example, the same material as the sintering aid that may be contained in the electrode layers (positive electrode layer 112 and negative electrode layer 114).

[0042] (End Surface Electrode) The end surface electrode 120 is disposed on an end surface of the substantially rectangular parallelepiped solid battery stack 110. The end surface electrode 120 may also be disposed on a portion of the side surface of the solid battery stack 110. The end surface electrode 120 preferably contains a conductive material with high conductivity. The material constituting the end surface electrode 120 is not particularly limited, but may be at least one selected from the group consisting of silver, gold, platinum, aluminum, copper, tin, carbon, and nickel, for example.

[0043] (Substrate) The substrate 200 has a first main surface 212 facing the solid-state battery 100, a second main surface 214 facing the first main surface 212, and a first end surface 216 and a second end surface 218 that extend in a direction intersecting the first main surface 212 and the second main surface 214, for example, perpendicular to the first main surface 212 and the second main surface 214, and that face each other.

[0044] The first main surface 212 of the substrate 200 may have a planar size larger than the mounting surface of the solid-state battery 100. The first main surface 212 of the substrate 200 is provided with an upper substrate positive terminal 222 connected to the positive electrode end surface electrode 122 on one side and connected to the positive electrode wiring layer 232 on the other side, and an upper substrate negative terminal 224 connected to the negative electrode end surface electrode 124 on one side and connected to the negative electrode wiring layer 234 on the other side. The second main surface 214 of the substrate 200 is provided with a lower substrate positive terminal 242 connected to the positive electrode wiring layer 232 and a lower substrate negative terminal 244 connected to the negative electrode wiring layer 234. This configuration allows the solid-state battery 100 in the solid-state battery package 1000 to be electrically connected to other electronic components located outside the solid-state battery package 1000.

[0045] The substrate 200 supports the solid-state battery 100, covers the lower surface of the solid-state battery 100, and prevents the solid-state battery 100 from being exposed to the outside. This prevents moisture from entering the solid-state battery 100. From the viewpoint of preferably preventing moisture from entering the solid-state battery 100, the substrate 200 can further include a metal layer that extends in a direction substantially parallel to the first main surface 212 and is not electrically connected to the wiring layers 232, 234.

[0046] In one example, metal exterior body 400 can be joined to first main surface 212 of substrate 200 so that first end surface 216 of the substrate and outer surface 450 of metal exterior body 400 are flush with each other, and so that second end surface 218 of the substrate and outer surface 450 of metal exterior body 400 are flush with each other. Specifically, as a joining means, substrate 200 has metal wiring layer 225 at the end of first main surface 212 (see FIG. 2 , etc.), and metal exterior body 400 can be joined to this metal wiring layer 225.

[0047] The main constituent element of the substrate 200 may include a resin. That is, the substrate 200 may be a resin substrate. Such a resin may be a thermoplastic resin or a thermosetting resin. Examples of such resin substrates include printed wiring boards and flexible substrates. In another example, the main constituent element of the substrate 200 may include a ceramic. That is, the substrate 200 may be a ceramic substrate. Such a ceramic may be, for example, alumina. Examples of such ceramic substrates include an LTCC substrate and an HTCC substrate.

[0048] (Insulating Layer) The insulating layer 300 is a layer made of an insulating material. Examples of insulating materials for the insulating layer 300 include resin. The thickness of the insulating layer 300 is, for example, 0.1 to 30 μm. The insulating layer 300 covers the solid-state battery 100 and is interposed between the outer surface of the solid-state battery 100 and the inner surface of the metal exterior body 400, electrically insulating the two components.

[0049] (Metal Exterior Body) As described above, the metal exterior body 400 covers the insulating layer 300 and is bonded to the substrate 200. The thickness of the exterior body 400 is, for example, 10 μm to 200 μm. The metal exterior body 400 is an exterior body made of metal. Examples of constituent metals include aluminum and copper. With this configuration, electrical insulation between the solid-state battery 100 and the metal exterior body 400 can be ensured.

[0050] <Characteristic Parts of First Embodiment> Based on the basic configuration of the solid-state battery package 1000 described above, the characteristic parts of the first embodiment will be described below.

[0051] In the solid-state battery package 1000 of the first embodiment, a first feature is that the insulating layer 300 can be configured so that one side is in contact with the solid-state battery 100 and the other side is in contact with the metal exterior body 400. A second feature is that the metal exterior body 400 has a groove 440. The "groove" referred to in this specification refers to an elongated recessed portion. In light of this, the "groove" referred to in this specification can also be referred to as a recessed portion, a recessed portion, a non-penetrating portion, a notch, or a slit (particularly a slit with a bottom).

[0052] According to the first feature, it is possible to reduce the internal space between the metal exterior body 400 and the solid-state battery 100. By reducing this internal space, it is possible to reduce the volume of the battery package, thereby improving the overall battery energy density per unit volume.

[0053] Furthermore, when the battery is charged and discharged, the battery expands and contracts, and the stress caused by this expansion and contraction is concentrated at specific locations on the components of the solid-state battery package 1000 (such as the substrate 200 and the metal outer casing 400), which may result in damage to the components (such as the substrate 200 and the metal outer casing 400).

[0054] In this regard, according to the second feature, the metal exterior body 400 has the groove 440, and the groove 440 can be configured as a space (corresponding to a clearance). The presence of such a local space can prevent stress from being continuously transmitted in the local space of the groove of the metal exterior body 400 compared to when there is no local space. This prevents the stress from being transmitted to the interior of the metal exterior body 400 and to the substrate 200 side, thereby allowing the stress to be alleviated. As a result, damage to the components of the solid-state battery 100 (such as the substrate 200 and the metal exterior body 400) can be preferably avoided.

[0055] From the above, the solid-state battery package 1000 according to the first embodiment can improve the battery energy density and alleviate the stress that occurs during battery charge and discharge.

[0056] Furthermore, as described in the section on the basic configuration, a metal exterior body 400 is used as the exterior body, and the metal exterior body 400 is bonded to the substrate 200, thereby preventing moisture from penetrating into the solid-state battery 100 located inside. The term "moisture" used here is not limited to gaseous water (more specifically, water vapor in the atmosphere) but also includes liquid water. Examples of liquid water include minute droplets formed by condensation of gaseous water.

[0057] The groove 440 will be described in detail below.

[0058] First, the groove 440 can extend from the inner surface 460 of the metal exterior body 400. That is, the groove 440 is positioned on the inner surface 460 side.

[0059] Since the solid-state battery 100 is located inside the metal exterior body 400, stress caused by the expansion and contraction of the battery during charging and discharging can be transmitted from the inner surface 460 of the metal exterior body 400 to the inside of the metal exterior body 400 and to the substrate 200 side via the insulating layer 300.

[0060] Taking this into consideration, by positioning the groove portion 440 on the inner surface 460 side of the metal outer casing 400, it is possible to effectively prevent stress generated from the battery 100 located inside the metal outer casing 400 from being transmitted in the local space of the groove portion 440 on the inner surface 460 side.

[0061] This makes it possible to prevent the stress from being transmitted from the inner surface 460 of the metal exterior body 400 to the interior of the metal exterior body 400 and to the substrate 200 side, thereby enabling such stress to be alleviated more effectively.

[0062] The metal exterior body 400 may have a plurality of grooves 440. By providing a plurality of grooves 440, stress caused by expansion and contraction of the battery can be effectively alleviated.

[0063] Furthermore, the metal exterior body 400 may be composed of a plurality of metal exterior body units. In one example, a plurality of metal exterior body units may be provided, including a first metal exterior body unit 410, a second metal exterior body unit 420, and a third metal exterior body unit 430. Although not shown, the remaining two metal exterior body units may also be provided (see also FIG. 1 ).

[0064] As shown, one side of each of first metal exterior unit 410 and third metal exterior unit 430 can be bonded to first main surface 212 of substrate 200. The other side of each of first metal exterior unit 410 and third metal exterior unit 430 can be bonded to second metal exterior unit 420. This bonding does not necessarily mean complete bonding in which all interfaces are bonded together, but may be partial bonding in which the interfaces are only partially bonded together.

[0065] The partial joining described above can provide grooves 441 (440) at the partial joining locations between the first metal exterior unit 410 and the second metal exterior unit 420 and the partial joining locations between the second metal exterior unit 420 and the third metal exterior unit 430. In the first embodiment, the depth direction of grooves 441 provided on the upper surface side of solid state battery 100 extends in a direction perpendicular to main surfaces 212, 214 of substrate 200 in a cross-sectional view.

[0066] Furthermore, grooves 442 (440) may also be provided at the joint between the first metal exterior unit 410 and the first main surface 212 of the substrate 200, and at the joint between the third metal exterior unit 430 and the first main surface 212 of the substrate 200. In the first embodiment, the depth direction of the grooves 442 of the solid state battery 100 extends horizontally relative to the main surfaces 212, 214 of the substrate 200 in a cross-sectional view.

[0067] Furthermore, the grooves 440 of the metal exterior body 400 may include grooves 441 provided on the top surface 130 side of the solid-state battery 100. Expansion and contraction of the battery that may occur during charging and discharging of the battery is likely to occur in the stacking direction of the solid-state battery 100. In light of this, by providing the grooves 441 on the top surface 130 side of the solid-state battery 100, stress caused by expansion and contraction of the battery can be efficiently alleviated.

[0068] In a cross-sectional view, the metal exterior body 400 has a corner portion 470, and a groove 440 can be provided in the corner portion R. When the metal exterior body 400 has the corner portion 470, stress caused by the expansion and contraction of the battery is likely to occur in this corner portion 470 of the metal exterior body 400. Taking this into consideration, by providing the groove 440 in the corner portion 470, the stress caused by the expansion and contraction of the battery can be effectively and efficiently alleviated.

[0069] The groove 440 may have a depth of 30% to 70% of the thickness of the metal exterior body 400. The cross-sectional shape of the groove 440 may be, for example, a rectangle, a triangle, or a rectangle and a semicircle (the semicircle being the end side of the groove 440). Note that the "groove width W" referred to in this specification refers to the width of the groove at the opening start point in a cross-sectional view. Also, the "groove depth D" referred to in this specification refers to the length between the start point of the groove 440 and the end end of the groove 440 in a direction perpendicular to the width direction of the groove 440 in a cross-sectional view.

[0070] If the depth of groove 440 is less than 30% of the thickness of metal exterior body 400, the size of the space in groove 440 becomes relatively small, which may reduce the above-mentioned stress relaxation effect. On the other hand, if the depth exceeds 70%, the size of the space in groove 440 becomes relatively large, which may reduce the strength of exterior body 400 and cause damage to metal exterior body 400.

[0071] Furthermore, the depth dimension D of the groove 440 is greater than the width dimension W of the groove 440. With this configuration, the size of the joints on the outer surface of the metal exterior body 400 can be made relatively small. This makes it possible to preferably prevent moisture from penetrating into the interior through the joints.

[0072] Furthermore, the depth of the groove 440 may be one-third or more of the depth of the solid-state battery 100. Since stress caused by expansion and contraction of the battery may also occur in the depth direction of the battery, this configuration can effectively relieve the stress caused by expansion and contraction of the battery. In this specification, "depth" refers to the direction from one side (the front side) of the battery element to the other opposite side, and is perpendicular to the width and thickness directions of the electrode layers of the battery element.

[0073] [Manufacturing Method of Solid-State Battery Package] Hereinafter, a manufacturing method of the solid-state battery package 1000 according to the first embodiment will be described.

[0074] Fig. 7A is a process diagram schematically showing step 1 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. Fig. 7B is a process diagram schematically showing step 2 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. Fig. 7C is a process diagram schematically showing step 3 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. Fig. 7D is a process diagram schematically showing step 4 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure. Fig. 7E is a process diagram schematically showing step 5 of the method for manufacturing a solid-state battery package according to the first embodiment of the present disclosure.

[0075] The manufacturing method of the solid-state battery package 1000 according to the first embodiment includes the steps of: preparing a substrate 200; mounting the solid-state battery 100 on the substrate 200; covering the solid-state battery 100 with an insulating layer 300 so as to be in contact with the solid-state battery 100; and providing a metal exterior body 400 that is bonded to the substrate 200, covers the insulating layer 300 so as to be in contact with the insulating layer 300, and has a groove 440.

[0076] [Method for Manufacturing a Solid-State Battery Package] The subject matter of the present invention can be obtained by preparing a solid-state battery including a battery constituent unit having a positive electrode layer, a negative electrode layer, and a solid electrolyte between the electrodes, and then packaging the solid-state battery.

[0077] The production of the solid state battery of the present invention can be broadly divided into the production of the solid state battery itself (hereinafter also referred to as "pre-packaged battery"), which corresponds to a stage before packaging, the preparation of the substrate, and packaging.

[0078] <<Method for Manufacturing Pre-packaged Battery>> The pre-packaged battery can be manufactured by a printing method such as screen printing, a green sheet method using a green sheet, or a combination of these. That is, the pre-packaged battery itself may be manufactured in accordance with a conventional method for manufacturing solid-state batteries (therefore, raw materials such as the solid electrolyte, organic binder, solvent, optional additives, positive electrode active material, and negative electrode active material described below may be those used in the manufacture of known solid-state batteries).

[0079] In the following, one production method will be described as an example for better understanding of the present invention, but the present invention is not limited to this method. Furthermore, the order of the following description and other chronological matters are merely for the convenience of explanation and are not necessarily binding.

[0080] (Laminate Block Formation) A solid electrolyte layer paste is prepared by mixing a solid electrolyte, an organic binder, a solvent, and optional additives. A positive electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and optional additives are mixed to prepare a positive electrode layer paste. Similarly, a negative electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and optional additives are mixed to prepare a negative electrode layer paste. The solid electrolyte layer paste is printed on a substrate (e.g., a PET film) to obtain a solid electrolyte layer green sheet. The positive electrode layer paste is printed on the substrate, and a current collecting layer and / or a negative layer are printed as needed to obtain a positive electrode layer green sheet. Similarly, the negative electrode layer paste is printed on the substrate, and a current collecting layer and / or a negative layer are printed as needed to obtain a negative electrode layer green sheet. After peeling each green sheet from the substrate, the positive electrode layer green sheet and the negative electrode layer green sheet are stacked so that they face each other via the solid electrolyte green sheet to obtain a laminate. The outermost layer (top layer and / or bottom layer) of the laminate may be an electrolyte layer, an insulating layer, or an electrode layer.

[0081] (Formation of fired battery body) After the laminate is pressure-bonded and integrated, it is cut to a predetermined size. The obtained cut laminate is subjected to degreasing and firing. This results in a fired laminate, i.e., a solid state battery laminate 110. Note that the laminate may be degreased and fired before cutting, and then cut.

[0082] (Formation of End Electrodes) The positive end electrode 122 can be formed by applying a conductive paste to the exposed positive electrode side of the fired laminate. Similarly, the negative end electrode 124 can be formed by applying a conductive paste to the exposed negative electrode side of the fired laminate. The positive and negative end electrodes may be provided so as to extend to the main surfaces of the fired laminate. The component of the end electrode may be at least one selected from silver, gold, platinum, aluminum, copper, tin, carbon, and nickel.

[0083] The positive and negative end electrodes 120 do not necessarily have to be formed after firing of the laminate, but may be formed before firing and then subjected to simultaneous firing.

[0084] By going through the above steps, a desired pre-packaged battery (corresponding to the solid-state battery 100) can finally be obtained.

[0085] <Preparation of Substrate> In this step, a substrate is prepared.

[0086] Although not particularly limited, when a resin substrate is used as the substrate, its preparation may be carried out by stacking multiple layers and then heating and pressurizing them. For example, a substrate precursor is formed using a resin sheet composed of a base fiber cloth impregnated with a resin material. After forming the substrate precursor, this substrate precursor is subjected to heating and pressure in a press. On the other hand, when a ceramic substrate is used as the substrate, its preparation may be carried out, for example, by thermocompression bonding multiple green sheets to form a green sheet laminate and then firing the green sheet laminate to obtain a ceramic substrate. The preparation of the ceramic substrate may be carried out, for example, in accordance with the preparation of an LTCC substrate. A semi-lacquer substrate may have vias and / or lands. In such cases, for example, holes may be formed in the green sheets using a punch press or a carbon dioxide laser, and the holes may be filled with a conductive paste material, or precursors of conductive portions such as vias and lands may be formed by a printing method or the like. Note that lands and the like may also be formed after firing the green sheet laminate.

[0087] After the substrate is prepared, upper substrate electrode terminals 222, 224 are formed on the first main surface 212 of the substrate 200 for electrical connection (see FIG. 7A). The substrate electrode layer may be subjected to an appropriate patterning process. By going through the above steps, the desired substrate can finally be obtained.

[0088] <<Packaging>> Next, the battery and substrate obtained above are packaged.

[0089] First, a pre-packaged battery (solid-state battery 100 with end electrodes) is mounted on a substrate 200 (see FIG. 7B ). In other words, an “unpackaged solid-state battery” is placed on the substrate (hereinafter, a battery to be used for packaging will also be simply referred to as a “solid-state battery”).

[0090] Specifically, the solid-state battery 100 is placed on the substrate 200 so that the upper substrate electrode terminals 222, 224 and the end surface electrodes 120 of the solid-state battery are electrically connected to each other. At this time, before placing the solid-state battery 100, for example, a conductive paste (e.g., Ag conductive paste) may be provided on the upper substrate electrode layer of the substrate 200, thereby electrically connecting the upper substrate electrode terminals 222, 224 of the support substrate and the end surface electrodes 120 of the solid-state battery to each other, respectively.

[0091] Next, the insulating layer 300 is coated on the solid-state battery 100 so as to be in contact with the solid-state battery 100 (see FIG. 7C). Specifically, when the insulating layer 300 is made of a resin material, the insulating layer 300 can be formed by a dipping method.

[0092] Next, metal exterior body 400 is provided, which is bonded to substrate 200, covers insulating layer 300 so as to be in contact with insulating layer 300, and has grooves 440 (FIGS. 7D and 7E).

[0093] In one example, metal exterior body 400 is configured from multiple metal exterior body units 410, 420, 430, etc. Because Fig. 7D is a cross-sectional view, the remaining two metal exterior body units may be provided, although they are not shown (see also Fig. 1).

[0094] The following description is based on the cross-sectional configuration. In this case, first metal exterior unit 410 is disposed on first main surface 212 of substrate 200, on one outside of solid-state battery 100 covered with insulating layer 300 previously disposed.

[0095] Furthermore, third metal exterior body unit 430 is disposed on first main surface 212 of substrate 200, on the other outside of solid state battery 100 covered with previously disposed insulating layer 300, so as to face first metal exterior body unit 410. Furthermore, although not shown, two other metal exterior body units are disposed so as to face each other.

[0096] Furthermore, the second metal exterior body unit 420 is placed on the insulating layer 300 between the first metal exterior body unit 410, the third metal exterior body unit 430, and two other metal exterior body units (not shown) so as to be close to each of the units 410, 430, etc. Thereafter, a laser or the like is irradiated from the outside to the interface between the first metal exterior body unit 410 and the second metal exterior body unit 420, the interface between the second metal exterior body unit 420 and the third metal exterior body unit 430 (also see FIG. 3 ), the interface between the first metal exterior body unit 410 and the first main surface 212 of the substrate 200, the interface between the third metal exterior body unit 430 and the first main surface 212 of the substrate 200, and the interfaces based on the other two metal exterior body units (not shown), thereby partially welding each interface and forming welds 480, thereby partially joining the respective components together. A groove 440 can be formed in each of these joints.

[0097] In one example, such grooves 440 are formed by external welding, and therefore, multiple grooves 440 may be configured to extend from the inner surface of metal exterior body 400. Furthermore, in the above method, grooves 440 may be positioned at the interface between substrate 200 and metal exterior body and on the upper surface side of solid state battery 100. Furthermore, in the above method, metal exterior body 400, which may be made up of multiple metal exterior body units, has corner portions 470, and grooves 440 may be provided in these corner portions 470 in a cross-sectional view.

[0098] The manner in which groove portion 440 is formed is not limited to the above-described manner, and cutting may be performed in advance using a cutting tool or the like on predetermined locations of any metal exterior body unit or a single metal exterior body 400, and after cutting, the metal exterior body units may be combined to form metal exterior body 400. When a single metal exterior body 400 is used, exterior body 400 with groove portion 440 may be formed by bending or curving a plate-shaped metal exterior body member at multiple locations.

[0099] By going through the steps described above, the solid state battery package 1000 according to the first embodiment of the present disclosure can be manufactured.

[0100] <Second to Fourth Embodiments> The solid-state battery packages according to the second to fourth embodiments differ from the solid-state battery package 1000 according to the first embodiment in that the orientation of the groove portion 441 arranged on the upper surface side of the solid-state battery 100 is different. In the following, to avoid duplication, this different configuration will be mainly described.

[0101] 4 is a cross-sectional view schematically illustrating the configuration of a solid-state battery package according to a second embodiment of the present disclosure. In the second embodiment, in the cross-sectional view, the depth direction of a groove 441A provided on the upper surface side of the solid-state battery 100 extends horizontally relative to the main surfaces 212 and 214 of the substrate 200.

[0102] Even in this horizontal arrangement, as in the first embodiment, the arrangement of the groove 441A allows the presence of an internal local space (corresponding to a clearance) formed in the groove 441A to suppress the continuous transmission of stress in the local space of the groove in the metal exterior body 400A compared to when there is no local space. This prevents the stress from being transmitted to the interior of the metal exterior body 400A and to the substrate 200 side, thereby enabling the stress to be alleviated. As a result, damage to the components of the solid-state battery 100 (such as the substrate 200 and the metal exterior body 400A) can be effectively avoided.

[0103] 5 is a cross-sectional view schematically illustrating the configuration of a solid-state battery package according to a third embodiment of the present disclosure. In the third embodiment, in a cross-sectional view, the depth direction of a groove 441B provided on the upper surface side of the solid-state battery 100 extends in a direction oblique to the main surfaces 212 and 214 of the substrate 200.

[0104] Compared to the first and second embodiments, this oblique arrangement more effectively prevents both horizontal and vertical stresses that may arise due to battery expansion and contraction from being continuously transmitted through the local spaces in the grooves of the metal exterior body 400B. This more effectively prevents the stresses from being transmitted to the interior of the metal exterior body 400B and to the substrate 200, thereby further alleviating the stresses. As a result, damage to the components of the solid-state battery 100 (such as the substrate 200 and the metal exterior body 400B) can be more effectively avoided.

[0105] 6 is a cross-sectional view schematically illustrating the configuration of a solid-state battery package according to a fourth embodiment of the present disclosure. In the fourth embodiment, in a cross-sectional view, the depth direction of a groove 441C provided on the upper surface side of the solid-state battery 100 extends in a direction perpendicular to the main surfaces 212 and 214 of the substrate 200, and the vertically extending groove 441C and the upper surface of the solid-state battery 100 face each other.

[0106] Such a vertical arrangement allows for a reduction in the number of metal exterior units 410 described above compared to the first to third embodiments. This allows for a reduction in the number of joining points at the interfaces between adjacent metal exterior units compared to the first to third embodiments. As a result, the burden required for joining can be reduced, and as a result, the manufacturing efficiency of solid-state battery packages can be improved.

[0107] Aspects of a solid-state battery package according to the present disclosure are as follows. <1> A solid-state battery package comprising: a substrate; a solid-state battery provided on the substrate; an insulating layer covering the solid-state battery so as to be in contact with the solid-state battery; and a metal exterior body covering the insulating layer so as to be in contact with the insulating layer and joined to the substrate, wherein the metal exterior body has a groove. <2> The solid-state battery package according to <1>, in which the groove extends from an inner surface of the metal exterior body. <3> The solid-state battery package according to <1> or <2>, in which a plurality of grooves are provided. <4> The solid-state battery package according to any one of <1> to <3>, in which the metal exterior body is composed of a plurality of metal exterior body units, and adjacent metal exterior body units are partially joined to each other and between the metal exterior body units and the substrate. <5> The solid-state battery package according to <4>, in which the groove is provided at a partial joint between adjacent metal exterior body units and at a joint between the metal exterior body unit and the substrate. <6> The solid-state battery package according to any one of <1> to <5>, wherein the metal exterior body includes a groove provided on an upper surface of the solid-state battery. <7> The solid-state battery package according to <6>, wherein, in a cross-sectional view, the metal exterior body has a corner portion, and the groove is provided in the corner portion. <8> The solid-state battery package according to <7>, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface of the solid-state battery extends horizontally with respect to the main surface of the substrate. <9> The solid-state battery package according to <7>, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface of the solid-state battery extends obliquely with respect to the main surface of the substrate. <10> The solid-state battery package according to <6>, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface of the solid-state battery extends vertically with respect to the main surface of the substrate, and the groove extending in the vertical direction faces the upper surface of the solid-state battery. <11> The solid-state battery package according to any one of <1> to <10>, wherein the groove has a depth that is 30% to 50% of the thickness of the metal exterior body. <12> The solid-state battery package according to any one of <1> to <11>, wherein the depth dimension of the groove is greater than the width dimension of the groove.<13> The solid-state battery package according to any one of <1> to <12>, wherein the depth length of the groove is one-third or more of the depth length of the solid-state battery. <14> The solid-state battery package according to any one of <1> to <13>, wherein the metal exterior body is partially joined to the substrate. <15> A method for manufacturing a solid-state battery package, comprising the steps of: preparing a substrate; mounting a solid-state battery on the substrate; coating the solid-state battery with an insulating layer so as to be in contact with the solid-state battery; and providing a metal exterior body joined to the substrate, covering the insulating layer so as to be in contact with the insulating layer, and having a groove. <16> The method for manufacturing a solid-state battery package according to <15>, wherein the metal exterior body is composed of a plurality of metal exterior body units, and the groove is formed by partially joining adjacent metal exterior body units. <17> The method for manufacturing a solid-state battery package according to <16>, wherein the partial joining of adjacent metal exterior body units and the joining of the metal exterior body to the substrate are performed by welding. <18> A method for manufacturing a solid-state battery package according to any one of <15> to <17>, wherein the metal exterior body has the groove extending from an inner surface of the metal exterior body. <19> A method for manufacturing a solid-state battery package according to any one of <15> to <18>, wherein a plurality of the grooves are provided. <20> A method for manufacturing a solid-state battery package according to any one of <15> to <19>, wherein the metal exterior body is provided so that the grooves are located at the interface with the substrate and on the upper surface side of the solid-state battery. <21> A method for manufacturing a solid-state battery package according to any one of <15> to <20>, wherein the metal exterior body has corner portions, and the grooves are provided in the corner portions in a cross-sectional view.

[0108] The solid-state battery package according to the present disclosure can be used in applications that typically require the use of electrical energy. For example, the solid-state battery package according to the present disclosure can be used in various fields where power storage is required. Although merely illustrative, the (secondary) battery of the present disclosure can be used in the electrical, information, and communications fields where electrical and electronic devices are used (for example, the electrical and electronic device fields or mobile device fields including mobile phones, smartphones, laptop computers, digital cameras, activity monitors, arm computers, electronic paper, wearable devices, and small electronic devices such as RFID tags, card-type electronic money, and smart watches), household and small industrial applications (for example, power tools, golf carts, and household, 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 power generation systems, road conditioners, smart grids, and general household installation-type power storage systems), medical applications (medical devices such as earphone hearing aids), pharmaceutical applications (dose management systems), as well as the IoT field, and space and deep-sea applications (for example, space probes, submersible research vessels, and the like).

[0109] REFERENCE SIGNS LIST 1000, 1000A, 1000B, 1000C Solid-state battery package 100 Solid-state battery 110 Solid-state battery stack 112 Positive electrode layer 114 Negative electrode layer 116 Solid electrolyte layer 120 End electrode 200 Substrate 212 First main surface 214 Second main surface 216 First end surface 218 Second end surface 300 Insulating layer 400, 400A, 400B, 400C Exterior body 410, 410A, 410B, 410C First metal exterior body unit 420, 420A, 420B, 420C Second metal exterior body unit 430, 430A, 430B Third metal exterior body unit

Claims

1. circuit board and A solid battery provided on the substrate, An insulating layer covering the solid battery so as to be in contact with the solid battery, A metal casing that covers the insulating layer so as to be in contact with the insulating layer and is joined to the substrate. Equipped with, A solid battery package in which the metal casing has grooves.

2. The solid battery package according to claim 1, wherein the groove extends from the inner surface of the metal casing.

3. The solid battery package according to claim 1, wherein a plurality of grooves are provided.

4. The solid battery package according to claim 1, wherein the metal casing is composed of a plurality of metal casing units, and adjacent metal casing units and the metal casing units and the substrate are partially joined to each other.

5. The solid battery package according to claim 4, wherein the grooves are provided at the partial joining locations of adjacent metal casing units and at the joining locations between the metal casing units and the substrate.

6. The solid battery package according to claim 1, wherein the metal casing includes a groove provided on the upper surface side of the solid battery.

7. The solid battery package according to claim 6, wherein, in cross-sectional view, the metal casing has a corner portion, and the groove portion is provided in the corner portion.

8. The solid battery package according to claim 7, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface side of the solid battery extends horizontally with respect to the main surface of the substrate.

9. The solid battery package according to claim 7, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface side of the solid battery extends diagonally with respect to the main surface of the substrate.

10. The solid battery package according to claim 6, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface side of the solid battery extends perpendicularly to the main surface of the substrate, and the groove extending perpendicularly faces the upper surface of the solid battery.

11. The solid battery package according to claim 1, wherein the groove portion has a depth of 30% to 50% of the thickness of the metal casing.

12. The solid battery package according to claim 1, wherein the depth dimension of the groove is greater than the width dimension of the groove.

13. The solid battery package according to claim 1, wherein the depth of the groove is one-third or more of the depth of the solid battery.

14. The solid battery package according to claim 1, wherein the metal casing is partially bonded to the substrate.

15. The process of preparing the circuit board, A step of mounting a solid battery onto the aforementioned substrate, A step of coating the solid battery with an insulating layer so as to be in contact with the solid battery, A step of providing a metal exterior body that is bonded to the substrate, covers the insulating layer so as to be in contact with the insulating layer, and has grooves. A method for manufacturing a solid battery package, including [the specified component].

16. The above metal casing is composed of multiple metal casing units, A method for manufacturing a solid battery package according to claim 15, comprising partially joining adjacent metal casing units to form the groove portion.

17. A method for manufacturing a solid battery package according to claim 16, wherein the partial joining of adjacent metal casing units and the joining of the metal casing to the substrate are performed by welding.

18. A method for manufacturing a solid battery package according to claim 15, comprising providing the metal casing having the groove extending from the inner surface of the metal casing.

19. A method for manufacturing a solid battery package according to claim 15, wherein a plurality of grooves are provided.

20. The method for manufacturing a solid battery package according to claim 15, wherein the metal casing is provided such that the groove portion is located at the interface with the substrate and on the upper surface side of the solid battery.

21. The method for manufacturing a solid battery package according to claim 15, wherein the metal casing has a corner portion, and the groove portion is provided in the corner portion in a cross-sectional view.