WO2025204301A1 - Solid-state battery package and manufacturing method therefor - Google Patents

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

This disclosure relates to a solid-state battery package (particularly, a solid-state battery packaged to facilitate substrate mounting) and a method for manufacturing the same.

Secondary batteries, which can be repeatedly charged and discharged, have long been used for a variety of purposes. For example, secondary batteries are used as power sources for electronic devices such as smartphones and laptops.

In secondary batteries, a liquid electrolyte is generally used as a medium for the ion movement that contributes to charging and discharging. In other words, a so-called electrolytic solution is used in secondary batteries. However, safety is generally required in such secondary batteries to prevent leakage of the electrolytic solution. Furthermore, since organic solvents and other materials used in the electrolytic solution are flammable, safety is also required in this regard.

In response, research is underway into solid-state batteries that use solid electrolytes instead of liquid electrolytes. Patent Document 1 discloses one such solid-state battery that includes a battery element and an exterior body that houses the battery element and has an internal space.

JP 2010-118159 A

The inventors of the present application have discovered that there are areas in which conventional solid-state batteries need to be improved. Specifically, if the exterior body has an internal space, this could result in a decrease in battery energy density. Furthermore, when the battery is charged and discharged, the battery elements expand and contract. If the stress caused by this expansion and contraction is concentrated in certain areas of the battery components, there is a risk that these components may be damaged.

The present disclosure therefore aims to provide a solid-state battery package that can improve battery energy density and alleviate stress that occurs during battery charging and discharging.

In order to achieve the above object, the present disclosure provides:
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;
a metal exterior body that covers the insulating layer so as to be in contact with the insulating layer and is joined to the substrate;
A solid-state battery package is provided, wherein the metal outer body has a groove.

In order to achieve the above object, the present disclosure provides:
providing 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;
providing a metal exterior body bonded to the substrate, covering the insulating layer so as to be in contact with the insulating layer, the metal exterior body having a groove.

The solid-state battery package disclosed herein can improve battery energy density and alleviate stress that occurs during battery charging and discharging.

FIG. 1 is a perspective view schematically illustrating 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 line AA in FIG. 1) that schematically illustrates the configuration of a solid-state battery package according to an embodiment of the present disclosure. FIG. 3 is an enlarged cross-sectional view that schematically shows the configuration of a corner portion (circled portion) of the metal exterior body of FIG. FIG. 4 is a cross-sectional view schematically showing the configuration of a solid-state battery package according to the second embodiment of the present disclosure. FIG. 5 is a cross-sectional view schematically showing 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 showing 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.

Below, a solid-state battery package, which is one aspect of the present disclosure, will be described in detail through embodiments. The description will refer to the drawings as necessary. The drawings include some schematic illustrations to facilitate understanding of the present disclosure, and may not reflect actual dimensions or proportions.

[Solid-state battery package]
The term "cross-sectional view" as used herein refers to a view taken from a direction perpendicular to the main surface of the substrate in the solid-state battery package.

The terms "upper-lower direction" and "left-right direction" used directly or indirectly in this specification correspond to the upper-lower direction and left-right direction in the drawings, respectively. Unless otherwise specified, the same symbols or signs indicate the same components, parts, or the same meaning. In one preferred embodiment, the vertically downward direction (i.e., the direction in which gravity acts) can be considered to correspond to the "downward direction"/"bottom side (lower surface side)," and the opposite direction can be considered to correspond to the "upward direction"/"top side (upper surface side, top surface side)."

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

First Embodiment
Fig. 1 is a perspective view schematically illustrating 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 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 in Fig. 2.

As shown in FIGS. 1 to 3, the solid-state battery package 1000 according to the first embodiment can be broadly divided into the following components:
a substrate 200;
a solid-state battery (100) provided on a substrate (200) and having end electrodes (120) on end surfaces;
an insulating layer 300 covering the solid-state battery 100 with the end electrodes 120;
The metal exterior body 400 covers the insulating layer 300 and is joined to the substrate 200 .

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.

Below, we will first explain the basic configuration of the solid-state battery package 1000. Then, we will explain the characteristic features of the first embodiment.

<Basic structure 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.

The solid-state battery 100 is a stacked solid-state battery configured such that each layer constituting a battery unit is stacked on top of each other, and each such layer is preferably made of a fired body.
The solid-state battery 100 has a substantially rectangular solid-state battery stack 110 and two opposing end electrodes 120 arranged 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 also serves as an electrode layer, is electrically connected to the other of the two terminal electrodes 120. The solid-state battery 100 is placed on the substrate 200 so 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.

In this specification, the term "solid-state battery" refers broadly to a battery whose components are made of solids, and narrowly to an all-solid-state battery whose components (particularly preferably all components) are made of solids. Examples of solid-state batteries 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.

(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 material 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.

-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.

=Cathode active material=
Examples of positive electrode active materials capable of absorbing and releasing lithium ions include 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 LiCo1 _/ 3Ni1/ _{3Mn1 / 3O2 .} Examples of lithium-containing oxides having a spinel structure include _LiMn2O4 and/or _{LiNi0.5Mn1.5O4} . 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).

In addition, the positive electrode active material capable of absorbing and releasing sodium ions may be, 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. An example of the positive electrode active material may be at least one selected from _the group consisting of _sodium - _containing phosphate compounds such as _Na3V2 ( _PO4 ) ₃ , _NaCoFe2 ( _PO4 ) _{3 , Na2Ni2Fe} ( _PO4 ) ₃ , _Na3Fe2 ( _PO4 ) ₃ , _{Na2FeP2O7 ,} and _Na4Fe3 ( _PO4 ) ₂ ( _P2O7 ) _, and sodium-containing layered oxides such as _NaFeO2 .

Other examples of positive electrode active materials 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.

=Negative electrode active material=
Examples of negative electrode active materials capable of absorbing and releasing lithium ions include 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 Li ₃ V ₂ (PO ₄ ) ₃ and/or LiTi ₂ (PO ₄ ) _3. An example of a lithium-containing phosphate compound having an olivine structure is Li ₃ Fe ₂ (PO ₄ ) ₃ and/or LiCuPO ₄ . An example of a lithium-containing oxide having a spinel structure is Li ₄ Ti ₅ O ₁₂ .

Furthermore, 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.

-Conductive materials-
The conductive material may be 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.

- Sintering aid -
The sintering aid may be, for example, at least one selected from the group consisting of lithium oxide, sodium oxide, potassium oxide, boron oxide, silicon oxide, bismuth oxide, and phosphorus oxide.

- Current collecting layer -
The current collecting layers (positive electrode current collecting layer and negative electrode current collecting layer) may each have the form of a foil. Here, if it is more important to improve electronic conductivity through co-firing, reduce the manufacturing cost of the solid-state battery 100, and/or reduce the internal resistance of the solid-state battery 100, the current collecting layers may have the form of a sintered body. The positive electrode current collecting layer and the negative electrode current collecting 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 collecting layers (positive electrode current collecting layer and negative electrode current collecting layer) may have an electrical connection portion for electrical connection to the outside and may be configured to be electrically connectable to the end electrode 120. When the current collecting 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.

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.

(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 extend out 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 to 500 μm, particularly 1 μm to 200 μm. 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.

-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.

A solid electrolyte capable of conducting lithium ions will now be described.
Examples of crystalline solid electrolytes include oxide-based crystalline materials and sulfide-based crystalline materials. Examples of oxide-based crystalline materials include lithium-containing phosphate compounds with a Nasicon structure, oxides with a perovskite structure, oxides with garnet or garnet-like structures, and oxide glass ceramic lithium ion conductors. Examples of lithium-containing phosphate compounds with a Nasicon structure include _LixMy ( _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)). Examples of lithium-containing _phosphate compounds with a Nasicon structure include _{Li1.2Al0.2Ti1.8} ( _PO4 ) ₃ . Examples of oxides with a perovskite structure include _{La0.55Li0.35TiO3 .} An example of an oxide having a garnet-type or garnet-like structure is Li ₇ La ₃ Zr ₂ O ₁₂ .

Furthermore, examples of sulfide-based crystalline materials include thio-LISICON, such as Li _3.25 Ge _0.25 P _0.75 S ₄ and Li ₁₀ GeP ₂ S _12. The crystalline solid electrolyte may contain a polymer material (e.g., polyethylene oxide (PEO)).

Examples of glass-based solid electrolytes include oxide- _{based glass materials and sulfide-based glass materials. Examples of oxide-based glass materials include 50Li4SiO4.50Li3BO3 . Examples of sulfide - based glass materials include 30Li2S.26B2S3.44LiI} , _{63Li2S.36SiS2.1Li3PO4 , 57Li2S.38SiS2.5Li4SiO4 , 70Li2S.30P2S5 , and 50Li2S.50GeS2 .}

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 phosphate compounds containing lithium, aluminum, and titanium as constituent elements (LATP) and phosphate compounds containing _lithium , aluminum, _{and germanium as} constituent elements (LAGP). Examples of LATP include _{Li1.07Al0.69Ti1.46} ( _PO4 ) ₃ . Examples of LAGP include _{Li1.5Al0.5Ge1.5} ( _PO4 ).
Examples of sulfide-based glass ceramic materials include Li ₇ P ₃ S ₁₁ and Li _3.25 P _0.95 S ₄ .

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 (PO ₄ ) ₃ (1≦x≦2, 1≦y≦2, M is at least one selected from the group consisting of Ti, Ge, Al, Ga, and Zr).

- 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).

(end face electrode)
The end surface electrodes 120 are disposed on end surfaces of the substantially rectangular parallelepiped solid battery stack 110. The end surface electrodes 120 may also be disposed on part of the side surfaces of the solid battery stack 110.
The end electrode 120 preferably contains a conductive material with high conductivity. The material constituting the end 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.

(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 extending in a direction intersecting the first main surface 212 and the second main surface 214, for example at right angles, and facing each other.

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 on one side to the positive electrode end surface electrode 122 and the other side to the positive electrode wiring layer 232, and an upper substrate negative terminal 224 connected on one side to the negative electrode end surface electrode 124 and the other side to the negative electrode wiring layer 234. The second main surface 214 of the substrate 200 is also 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.

The substrate 200 supports the solid-state battery 100, covers the underside 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. To effectively prevent moisture from entering the solid-state battery 100, the substrate 200 can further include a metal layer that extends in a direction approximately parallel to the first main surface 212 and is not electrically connected to the wiring layers 232, 234.

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

The main component 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 components of the substrate 200 may include ceramics. That is, the substrate 200 may be a ceramic substrate. Such ceramics may be, for example, alumina. Examples of such ceramic substrates include an LTCC substrate and an HTCC substrate.

(insulating layer)
The insulating layer 300 is a layer made of an insulating material. Examples of the insulating material 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.

(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.

<Characteristic features of the first embodiment>
Based on the basic configuration of the solid-state battery package 1000 described above, the characteristic features of the first embodiment will be described below.

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. In this specification, the term "groove" refers to a long, narrow recessed portion. With this in mind, the term "groove" in this specification can also be referred to as a recessed portion, a concave portion, a non-penetrating portion, a notch, or a slit (particularly a slit with a bottom).

According to the first feature, the internal space between the metal exterior body 400 and the solid-state battery 100 can be reduced. This reduction in internal space allows the volume of the battery package to be reduced, thereby improving the overall battery energy density per unit volume.

Furthermore, when the battery is charged and discharged, the battery expands and contracts. The stress caused by this expansion and contraction is concentrated at specific locations on the components of the solid-state battery package 1000 (substrate 200, metal exterior body 400, etc.), which could damage these components (substrate 200, metal exterior body 400, etc.).

In this regard, according to the second feature, the metal exterior body 400 has a 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, making it possible to alleviate such stress. As a result, damage to the components of the solid-state battery 100 (substrate 200, metal exterior body 400, etc.) can be preferably avoided.

From the above, it can be seen that the solid-state battery package 1000 according to the first embodiment can improve battery energy density and alleviate stress that occurs during battery charging and discharging.

Furthermore, as mentioned in the section on 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, which makes it possible to prevent moisture from penetrating into the solid-state battery 100 located inside. The "moisture" referred to here is not limited to gaseous water (more specifically, water vapor in the atmosphere), but also includes liquid water. Examples of liquid water include tiny droplets formed by condensation of gaseous water.

The groove portion 440 will be described in detail below.

First, the groove 440 can extend from the inner surface 460 of the metal exterior body 400. In other words, the groove 440 is positioned on the inner surface 460 side.

Because the solid-state battery 100 is located inside the metal exterior body 400, stress caused by 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 interior of the metal exterior body 400 and the substrate 200 side via the insulating layer 300.

In consideration of this, by positioning the grooves 440 on the inner surface 460 side of the metal exterior body 400, it is possible to effectively prevent stress generated by the battery 100 located inside the metal exterior body 400 from being transmitted in the local space of the grooves 440 on the inner surface 460 side.

This prevents 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, making it possible to more effectively alleviate the stress.

The metal exterior body 400 can have multiple grooves 440. By providing multiple grooves 440, stress caused by expansion and contraction of the battery can be effectively alleviated.

Furthermore, the metal exterior body 400 may be composed of multiple metal exterior body units. In one example, multiple 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 Figure 1).

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

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

Furthermore, grooves 442 (440) may 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.

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 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.

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

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, rectangular, triangular, or a rectangular and semicircular shape (the semicircular shape is the end of the groove 440). Note that, in this specification, the "groove width W" refers to the width of the groove at the opening start point in a cross-sectional view. Also, in this specification, the "groove depth D" refers to the length between the start point of the groove 440 and the end of the groove 440 in a direction perpendicular to the width direction of the groove 440 in a cross-sectional view.

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

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 effectively prevent moisture from penetrating into the interior through the joints.

Furthermore, the depth of the groove 440 can be one-third or more of the depth of the solid-state battery 100. Because stress caused by expansion and contraction of the battery can also occur in the depth direction of the battery, this configuration can effectively alleviate the stress caused by expansion and contraction of the battery. As used herein, "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 layer of the battery element.

[Method of manufacturing a solid-state battery package]
A method for manufacturing the solid-state battery package 1000 according to the first embodiment will be described below.

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.

The method for manufacturing the solid-state battery package 1000 according to the first embodiment includes the following steps:
preparing a substrate 200;
Mounting the solid-state battery 100 on the substrate 200;
a step of 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).

[Method of manufacturing a solid-state battery package]
The object of the present invention can be obtained by preparing a solid-state battery including a battery building block having a positive electrode layer, a negative electrode layer, and a solid electrolyte between the electrodes, and then packaging the solid-state battery.

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 the "pre-packaged battery"), which corresponds to the stage prior to packaging, the preparation of the substrate, and packaging.

<Manufacturing method of unpackaged batteries>
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 methods. That is, the pre-packaged battery itself may be manufactured in accordance with a conventional solid-state battery manufacturing method (thus, 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).

The following describes one manufacturing method as an example to facilitate a better understanding of the present invention, but the present invention is not limited to this method. Furthermore, the order of the following descriptions and other chronological matters are merely for the convenience of explanation and are not necessarily binding.

(Laminated block formation)
A paste for the solid electrolyte layer is prepared by mixing a solid electrolyte, an organic binder, a solvent, and any additives.
A paste for a positive electrode layer is prepared by mixing a positive electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and any additives. Similarly, a paste for a negative electrode layer is prepared by mixing a negative electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and any additives.
- Print the paste for the solid electrolyte layer on a substrate (e.g., a PET film) to obtain a green sheet for the solid electrolyte layer. - Print the paste for the positive electrode layer on the substrate, and if necessary, print a current collecting layer and/or a negative layer to obtain a green sheet for the positive electrode layer. - Similarly, print the paste for the negative electrode layer on the substrate, and if necessary, print a current collecting layer and/or a negative layer to obtain a green sheet for the negative electrode layer.
After peeling each green sheet from the substrate, the green sheet for the positive electrode layer and the green sheet for the negative electrode layer are stacked so that they face each other with the green sheet for the solid electrolyte interposed therebetween to obtain a laminate. Note that the outermost layer (the uppermost layer and/or the lowermost layer) of the laminate may be an electrolyte layer, an insulating layer, or an electrode layer.

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

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

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 fired simultaneously.

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

<Preparation of substrate>
In this step, the substrate is prepared.

While not particularly limited, when a resin substrate is used as the substrate, its preparation may be carried out by stacking multiple layers and applying heat and pressure. For example, a substrate precursor is formed using a resin sheet composed of a base fiber cloth impregnated with a resin material. After the substrate precursor is formed, 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. Ceramic substrates can be prepared, for example, in a manner similar to the manufacture of LTCC substrates. Semi-lacquer substrates may have vias and/or lands. In such cases, precursors for conductive portions such as vias and lands may be formed, for example, by forming holes in the green sheets using a punch press or carbon dioxide laser, and filling the holes with a conductive paste material, or by using a printing method or the like. Note that lands and the like can also be formed after firing the green sheet laminate.

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 Figure 7A). The substrate electrode layer may be patterned as appropriate. By going through the above steps, the desired substrate can finally be obtained.

Packaging
Next, the battery and substrate obtained above are packaged.

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

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 applied to 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.

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 Figure 7C). Specifically, if the insulating layer 300 is made of a resin material, the insulating layer 300 can be formed by a dipping method.

Next, a metal exterior body 400 is provided 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 (Figures 7D and 7E).

In one example, the metal exterior body 400 is made up of multiple metal exterior body units 410, 420, 430, etc. Figure 7D shows a cross-sectional view, so the remaining two metal exterior body units may be provided, although they are not shown (see also Figure 1).

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

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

Furthermore, a 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 adjacent 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.

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

Note that the manner in which the grooves 440 are formed is not limited to the above-described manner, and cutting may be performed in advance on predetermined locations of any metal exterior body unit or a single metal exterior body 400 using a cutting tool or the like, and after cutting, the metal exterior body 400 may be constructed by combining the metal exterior body units. When a single metal exterior body 400 is used, the plate-shaped metal exterior body member may be bent or curved at multiple locations to form an exterior body 400 with grooves 440.

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

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.

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. In the second embodiment, in cross-sectional view, the depth direction of the groove portion 441A provided on the upper surface side of the solid-state battery 100 extends horizontally relative to the main surfaces 212, 214 of the substrate 200.

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 clearance) formed in the groove 441A to prevent stress from being continuously transmitted 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, making it possible to alleviate such stress. As a result, damage to the components of the solid state battery 100 (substrate 200, metal exterior body 400A, etc.) can be preferably avoided.

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. In the third embodiment, the depth direction of the groove 441B provided on the upper surface of the solid-state battery 100 extends obliquely relative to the main surfaces 212, 214 of the substrate 200 in a cross-sectional view.

Compared to the first and second embodiments, this diagonal arrangement more effectively prevents both horizontal and vertical stresses that may arise due to the expansion and contraction of the battery from being continuously transmitted in the local space of the groove in the metal exterior body 400B. This more effectively prevents the above-mentioned stresses from being transmitted to the interior of the metal exterior body 400B and to the substrate 200 side, making it possible to further mitigate such stresses. As a result, damage to the components of the solid-state battery 100 (substrate 200, metal exterior body 400B, etc.) can be more effectively avoided.

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. In the fourth embodiment, in a cross-sectional view, the depth direction of the groove 441C provided on the upper surface of the solid-state battery 100 extends perpendicularly to the main surfaces 212, 214 of the substrate 200, and the vertically extending groove 441C faces the upper surface of the solid-state battery 100.

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.

Aspects of the solid-state battery package according to the present disclosure are as follows.
<1>
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;
a metal exterior body that covers the insulating layer so as to be in contact with the insulating layer and is joined to the substrate;
The solid-state battery package has a groove in the metal exterior body.

<2>
The solid-state battery package according to <1>, wherein the groove portion extends from an inner surface of the metal exterior body.

<3>
The solid-state battery package according to <1> or <2>, wherein a plurality of the grooves are provided.

＜4＞
<4> The solid-state battery package according to any one of <1> to <3>, wherein the metal exterior body is composed of a plurality of metal exterior body units, and adjacent metal exterior body units are partially bonded to each other, and a metal exterior body unit is partially bonded to the substrate.

<5>
The solid-state battery package according to <4>, wherein the grooves are provided at partial joints between adjacent metal exterior units and at joints between the metal exterior unit and the substrate.

<6>
<5> 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 side of the solid-state battery.

＜７＞
The solid-state battery package according to <6>, wherein the metal exterior body has a corner portion in a cross-sectional view, and the groove portion is provided in the corner portion.

＜8＞
The solid-state battery package according to <7>, wherein, in a cross-sectional view, a depth direction of the groove provided on the upper surface side 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, a depth direction of the groove provided on the upper surface side of the solid-state battery extends in a direction oblique to the main surface of the substrate.

<10>
The solid-state battery package according to <6>, wherein, in a cross-sectional view, a depth direction of the groove provided on the upper surface side of the solid-state battery extends in a direction perpendicular to the main surface of the substrate, and the groove extending in the perpendicular 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 of 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>
<13> The solid-state battery package according to any one of <1> to <12>, wherein the depth of the groove is at least one-third of the depth of the solid-state battery.

<14>
<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＞
providing 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;
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.

<16>
the metal exterior body is composed of a plurality of metal exterior body units,
The method for manufacturing a solid-state battery package according to <15>, wherein the groove portion 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 adjacent metal exterior body units are partially joined and the metal exterior body is joined to the substrate by welding.

＜18＞
<18> The 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＞
<19> The 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＞
<15> to <19>, wherein the metal exterior body is provided so that the groove portion is located at the interface with the substrate and on the upper surface side of the solid-state battery.

＜21＞
The method for manufacturing a solid-state battery package according to any one of <15> to <20>, wherein the metal exterior body has a corner portion, and the groove portion is provided in the corner portion in a cross-sectional view.

The solid-state battery package battery 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 a variety of fields where power storage is anticipated. By way of example only, the (secondary) battery of the present disclosure can be used in fields such as electricity, information, and communications where electrical and electronic devices are used (for example, electrical and electronic devices or mobile devices 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 harbor 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 power storage systems), medical applications (medical devices such as earphones and hearing aids), pharmaceutical applications (dose management systems), IoT, and space and deep-sea applications (for example, space probes and submersible research vessels).

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 (21)

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;
a metal exterior body that covers the insulating layer so as to be in contact with the insulating layer and is joined to the substrate;
The solid-state battery package has a groove in the metal exterior body. The solid-state battery package of claim 1, wherein the groove extends from the inner surface of the metal exterior body. The solid-state battery package described in claim 1 or 2, wherein a plurality of the grooves are provided. A solid-state battery package according to any one of claims 1 to 3, wherein the metal exterior body is composed of a plurality of metal exterior body units, and adjacent metal exterior body units and metal exterior body units and the substrate are partially bonded to each other. The solid-state battery package described in claim 4, wherein the grooves are provided at the partial joints between adjacent metal exterior units and at the joints between the metal exterior unit and the substrate. A solid-state battery package according to any one of claims 1 to 5, wherein the metal exterior body includes a groove provided on the upper surface of the solid-state battery. The solid-state battery package described in claim 6, wherein, in cross-sectional view, the metal exterior body has corner portions, and the groove portions are provided in the corner portions. The solid-state battery package described in claim 7, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface side of the solid-state battery extends horizontally relative to the main surface of the substrate. The solid-state battery package described in claim 7, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface side of the solid-state battery extends obliquely relative to the main surface of the substrate. The solid-state battery package of claim 6, wherein, in a cross-sectional view, the depth direction of the groove provided on the upper surface of the solid-state battery extends perpendicular to the main surface of the substrate, and the perpendicularly extending groove faces the upper surface of the solid-state battery. A solid-state battery package according to any one of claims 1 to 10, wherein the groove has a depth of 30% to 50% of the thickness of the metal exterior body. A solid-state battery package according to any one of claims 1 to 11, wherein the depth dimension of the groove is greater than the width dimension of the groove. A solid-state battery package according to any one of claims 1 to 12, wherein the depth of the groove is at least one-third of the depth of the solid-state battery. A solid-state battery package according to any one of claims 1 to 13, wherein the metal outer casing is partially bonded to the substrate. providing 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;
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. the metal exterior body is composed of a plurality of metal exterior body units,
The method for manufacturing a solid-state battery package according to claim 15 , wherein the groove portion is formed by partially joining adjacent metal exterior units. The method for manufacturing a solid-state battery package described in claim 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. A method for manufacturing a solid-state battery package according to any one of claims 15 to 17, wherein the metal outer casing is provided with a groove extending from the inner surface of the metal outer casing. The method for manufacturing a solid-state battery package described in any one of claims 15 to 18, wherein multiple grooves are provided. The method for manufacturing a solid-state battery package described in any one of claims 15 to 19, wherein the metal exterior body is provided so that the groove portion is located at the interface with the substrate and on the upper surface side of the solid-state battery. The method for manufacturing a solid-state battery package described in any one of claims 15 to 20, wherein the metal exterior body has corner portions, and the groove portions are provided in the corner portions in a cross-sectional view.