Packaged solid-state battery

Abstract

The present invention provides a packaged solid-state battery which is provided with: a substrate; a solid-state battery with an end face electrode, the solid-state battery being provided on the substrate; and an outer package that covers the solid-state battery. The outer package contains a resin. A void part is present between the end face electrode and the outer package.

Description

Packaged Solid-State Batteries

[0001] The present disclosure relates to packaged solid-state batteries, and more particularly, to solid-state batteries packaged in a manner conducive to substrate mounting.

[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 into solid-state batteries that use solid electrolytes instead of liquid electrolytes.

[0005] Special Publication No. 2010-503957

[0006] Solid-state batteries may be mounted on a substrate such as a printed wiring board together with other electronic components. A solid-state battery arranged on a substrate may be covered with a covering member to prevent water vapor from passing through (Patent Document 1). The covering member is arranged to cover the end electrodes of the solid-state battery. In this case, the end electrodes are in physical contact with the solid-state battery and may deform as the solid-state battery expands and contracts during charging and discharging. Meanwhile, the covering member is arranged on the solid-state battery via the end electrodes in the area where it covers the end electrodes. Therefore, compared to the end electrodes, the covering member is less able to follow the expansion and contraction of the solid-state battery and may act to prevent the end electrodes from deforming. As a result, distortion may occur inside the end electrodes, potentially damaging the end electrodes.

[0007] The present invention has been made in view of the above-mentioned problems. That is, a main object of the present disclosure is to provide a packaged solid-state battery in which the risk of damage to end electrodes due to expansion and contraction of the solid-state battery is reduced.

[0008] In order to achieve the above object, one embodiment of the present disclosure provides a packaged solid-state battery including: a substrate; a solid-state battery with end surface electrodes provided on the substrate; and an exterior part covering the solid-state battery, wherein the exterior part contains a resin; and a gap part is included between the end surface electrodes and the exterior part.

[0009] A packaged solid-state battery according to an embodiment of the present disclosure can reduce the risk of damage to the end electrodes due to expansion and contraction of the solid-state battery.

[0010] FIG. 1 is a cross-sectional view schematically showing the internal configuration of a solid-state battery. FIG. 2 is a cross-sectional view schematically showing the configuration of a packaged solid-state battery according to an embodiment of the present disclosure. FIG. 3 is an enlarged cross-sectional view schematically showing part A of the packaged solid-state battery shown in FIG. 2. FIG. 4 is an enlarged cross-sectional view schematically showing part A of a packaged solid-state battery according to another embodiment of the present disclosure. FIG. 5 is a cross-sectional view schematically showing the configuration of a packaged solid-state battery according to an embodiment of the present disclosure. FIG. 6 is an enlarged cross-sectional view schematically showing part B of the packaged solid-state battery shown in FIG. 5. FIG. 7A is a cross-sectional view schematically showing steps in a manufacturing process for a packaged solid-state battery according to an embodiment of the present disclosure. FIG. 7B is a cross-sectional view schematically showing steps in a manufacturing process for a packaged solid-state battery according to an embodiment of the present disclosure. FIG. 7C is a cross-sectional view schematically showing steps in a manufacturing process for a packaged solid-state battery according to an embodiment of the present disclosure. FIG. 7D is a cross-sectional view schematically showing steps in a manufacturing process for a packaged solid-state battery according to an embodiment of the present disclosure. FIG. 7E is a cross-sectional view schematically showing steps in a manufacturing process for a packaged solid-state battery according to an embodiment of the present disclosure.

[0011] The packaged solid-state battery of the present disclosure will be described in detail below. While the description will be made with reference to drawings as necessary, the contents shown in the drawings are merely shown as schematic examples for the purpose of understanding the present disclosure, and the appearance, dimensional ratio, etc. may differ from the actual product.

[0012] In this specification, the term "packaged solid-state battery" refers, in a broad sense, to a solid-state battery device configured to protect the solid-state battery from the external environment, and, in a narrow sense, to a solid-state battery device that includes a mountable substrate and protects the solid-state battery from the external environment.

[0013] The term "cross-sectional view" as used herein refers to the shape of a solid-state battery viewed from a direction substantially perpendicular to the stacking direction (in other words, the shape of a solid-state battery cut along a plane parallel to the thickness direction of the layers). The terms "planar view" and "planar shape" as used herein refer to a sketch of an object viewed from above or below along the thickness direction of the layers (i.e., the stacking direction).

[0014] 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 reference numerals or symbols indicate the same members or 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," and the opposite direction can be considered to correspond to the "upper direction" / "top side."

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

[0016] [Basic Configuration of Secondary Battery] In this specification, the term "secondary battery" refers to a battery that can be repeatedly charged and discharged. Therefore, the secondary battery according to the present disclosure is not limited to the name, and may also include, for example, an electricity storage device.

[0017] In the present disclosure, the term "solid-state battery" broadly refers to a battery whose components are made of solids, and narrowly refers to an all-solid-state battery whose components (particularly preferably all components) are made of solids. In a preferred embodiment, the solid-state battery in the present disclosure is a stacked solid-state battery in which each layer constituting a battery unit is stacked on top of each other, and preferably each such layer is made of a sintered body. The term "solid-state battery" encompasses not only so-called "secondary batteries" that can be repeatedly charged and discharged, but also "primary batteries" that can only discharge. According to a preferred embodiment of the present disclosure, the "solid-state battery" is a secondary battery. The term "secondary battery" should not be overly constrained by its name and can also include, for example, an energy storage device. In the present disclosure, a solid-state battery contained in a package can also be referred to as a "solid-state battery element."

[0018] The basic configuration of the solid-state battery of the present disclosure will be described below. The configuration of the solid-state battery described here is merely an example for understanding the invention and is not intended to limit the invention.

[0019] [Basic Structure of Solid-State Battery] A solid-state battery has at least positive and negative electrode layers and a solid electrolyte. Specifically, as shown in Fig. 1, a solid-state battery 100 includes a solid-state battery stack including battery constituent units each consisting of a positive electrode layer 110, a negative electrode layer 120, and at least a solid electrolyte 130 interposed therebetween.

[0020] The layers constituting the solid-state battery may be formed by firing, and the positive electrode layer, the negative electrode layer, the solid electrolyte, etc. may form fired layers. Preferably, the positive electrode layer, the negative electrode layer, and the solid electrolyte are each fired together, and therefore the solid-state battery laminate forms a fired body.

[0021] The positive electrode layer is an electrode layer containing at least a positive electrode active material. The positive electrode layer may further contain a solid electrolyte. In a preferred embodiment, the positive electrode layer is composed of a sintered body containing at least positive electrode active material particles and solid electrolyte particles. On the other hand, the negative electrode layer is an electrode layer containing at least a negative electrode active material. The negative electrode layer may further contain a solid electrolyte. In a preferred embodiment, the negative electrode layer is composed of a sintered body containing at least a negative electrode active material particles and solid electrolyte particles.

[0022] The positive electrode active material and the negative electrode active material are materials involved in the transfer of electrons in a solid-state battery. Charge and discharge are performed by the transfer of electrons through the solid electrolyte, which transfers ions between the positive electrode layer and the negative electrode layer (conduction). Each of the positive electrode layer and the negative electrode layer is preferably a layer capable of absorbing and releasing lithium ions or sodium ions. In other words, the solid-state battery is preferably an all-solid-state secondary battery in which lithium ions or sodium ions transfer between the positive electrode layer and the negative electrode layer through the solid electrolyte to charge and discharge the battery.

[0023] (Positive electrode active material) The positive electrode active material contained in the positive electrode layer can be selected from the group consisting of, for example, lithium-containing phosphate compound with Nasicon structure, lithium-containing phosphate compound with olivine structure, lithium-containing layered oxide, and lithium-containing oxide with spinel structure.An example of the lithium-containing phosphate compound with Nasicon structure is Li ３ V ２ (P.O. ４ ) ３ Examples of lithium-containing phosphate compounds having an olivine structure include Li ３ Fe ２ (P.O. ４ ) ３ , LiFePO ４ , and / or LiMnPO ４ An example of a lithium-containing layered oxide is LiCoO ２ , and / or LiCo １／３ Ni １／３ Mn １／３ O ２An example of a lithium-containing oxide having a spinel structure is LiMn ２ O ４ , and / or LiNi ０．５ Mn １．５ O ４ The lithium compound may be, for example, a lithium transition metal composite oxide or a lithium transition metal phosphate compound. The lithium transition metal composite oxide is a general term for oxides containing lithium and one or more transition metal elements as constituent elements, and the lithium transition metal phosphate compound is a general term for phosphate compounds containing lithium and one or more transition metal elements as constituent elements. The transition metal element may be, for example, cobalt (Co), nickel (Ni), manganese (Mn), or iron (Fe), for example.

[0024] In addition, the positive electrode active material capable of absorbing and releasing sodium ions may be at least one selected from the group consisting of sodium-containing phosphate compounds having a Nasicon structure, sodium-containing phosphate compounds having an olivine structure, sodium-containing layered oxides, and sodium-containing oxides having a spinel structure. For example, in the case of sodium-containing phosphate compounds, Na 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 , Na ４ Fe ３ (P.O. ４ ) ２ (P ２ O ７ ), and NaFeO as a sodium-containing layered oxide ２At least one selected from the group consisting of:

[0025] Alternatively, the positive electrode active material may be, for example, an oxide, a disulfide, a chalcogenide, or a conductive polymer. The oxide may be, for example, titanium oxide, vanadium oxide, or manganese dioxide. The disulfide may be, for example, titanium disulfide or molybdenum sulfide. The chalcogenide may be, for example, niobium selenide. The conductive polymer may be, for example, a disulfide, polypyrrole, polyaniline, polythiophene, polyparastyrene, polyacetylene, or polyacene.

[0026] (Negative Electrode Active Material) Examples of the negative electrode active material contained in the negative electrode layer 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 Li. ３ V ２ (P.O. ４ ) ３ , and / or LiTi ２ (P.O. ４ ) ３ Examples of lithium-containing phosphate compounds having an olivine structure include Li ３ Fe ２ (P.O. ４ ) ３ , and / or LiCuPO ４ Examples of lithium-containing oxides having a spinel structure include Li ４ Ti ５ O １２ etc.

[0027] 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.

[0028] In the solid-state battery, the positive electrode layer and the negative electrode layer may be made of the same material.

[0029] The positive electrode layer and / or the negative electrode layer may contain a conductive material, which may include at least one of metal materials such as silver, palladium, gold, platinum, aluminum, copper, and nickel, and carbon.

[0030] Furthermore, the positive electrode layer and / or the negative electrode layer may contain a sintering aid, such as at least one selected from the group consisting of lithium oxide, sodium oxide, potassium oxide, boron oxide, silicon oxide, bismuth oxide, and phosphorus oxide.

[0031] There are no particular limitations on the thickness of the positive electrode layer and the negative electrode layer, but for example, they may each independently be 2 μm or more and 50 μm or less, particularly 5 μm or more and 30 μm or less.

[0032] (Positive Electrode Current Collector Layer / Negative Electrode Current Collector Layer) Although not essential elements of the electrode layer, the positive electrode layer and the negative electrode layer may each comprise a positive electrode current collector layer and a negative electrode current collector layer. The positive electrode current collector layer and the negative electrode current collector layer may each have the form of a foil. However, if greater emphasis is placed on improving electronic conductivity through co-firing, reducing the manufacturing cost of the solid-state battery, and / or reducing the internal resistance of the solid-state battery, the positive electrode current collector layer and the negative electrode current collector layer may each have the form of a sintered body. The positive electrode current collector constituting the positive electrode current collector and the negative electrode current collector constituting the negative electrode current collector are preferably made of a material with high conductivity, such as silver, palladium, gold, platinum, aluminum, copper, and / or nickel. The positive electrode current collector and the negative electrode current collector may each have an electrical connection portion for electrical connection to the outside and may be configured to be electrically connectable to an end electrode. Note that when the positive electrode current collector and the negative electrode current collector have the form of a sintered body, they may be composed of a sintered body containing a conductive material and a sintering aid. The conductive materials 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 conductive materials that may be contained in the positive electrode layer and the negative electrode layer. 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 and the negative electrode layer. As described above, the positive electrode current collecting layer and the negative electrode current collecting layer are not necessarily required for a solid-state battery, and a solid-state battery that does not include such a positive electrode current collecting layer and a negative electrode current collecting layer is also conceivable. In other words, the solid-state battery included in the package of the present disclosure may be a solid-state battery without a current collecting layer.

[0033] (Solid Electrolyte) The solid electrolyte is a material capable of conducting lithium ions or sodium ions. In particular, the solid electrolyte constituting a battery unit in a solid-state battery may form a layer capable of conducting lithium ions between the positive electrode layer 110 and the negative electrode layer 120 (see FIG. 1 ). The solid electrolyte may be provided at least between the positive electrode layer and the negative electrode layer. In other words, the solid electrolyte may be present around the positive electrode layer and / or the negative electrode layer so as to protrude from between the positive electrode layer and the negative electrode layer. Specific solid electrolytes include, for example, one or more of a crystalline solid electrolyte, a glass-based solid electrolyte, a glass-ceramic-based solid electrolyte, and the like.

[0034] The crystalline solid electrolyte may be, for example, an oxide-based crystalline material or a sulfide-based crystalline material, etc. Examples of the oxide-based crystalline material include a lithium-containing phosphate compound having a Nasicon structure, an oxide having a perovskite structure, an oxide having a garnet-type or garnet-like structure, and an oxide glass ceramic-based lithium ion conductor.

[0035] The lithium-containing phosphate compound having a Nasicon structure includes 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 １２Examples of 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)).

[0036] 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 The sulfide glass material is, for example, 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 etc.

[0037] The glass ceramic solid electrolyte may be, for example, an oxide-based glass ceramic material or a sulfide-based glass ceramic material. As the oxide-based glass ceramic material, for example, a phosphate compound containing lithium, aluminum, and titanium as constituent elements (LATP) or a phosphate compound containing lithium, aluminum, and germanium as constituent elements (LAGP) may be used. LATP may be, for example, Li １．０７ Al ０．６９ Ti １．４６ (P.O. ４ ) ３ LAGP is, for example, Li １．５ Al ０．５ Ge１．５ (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 etc.

[0038] 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 (P.O. 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).

[0039] The solid electrolyte may contain a sintering aid. The sintering aid contained in the solid electrolyte may be selected from the same materials as the sintering aids that may be contained in the positive electrode layer and the negative electrode layer, for example.

[0040] The thickness of the solid electrolyte is not particularly limited. The thickness of the solid electrolyte layer located between the positive electrode layer and the negative electrode layer may be, for example, 1 μm to 15 μm, particularly 1 μm to 5 μm.

[0041] (End Electrodes) The solid-state battery 100 is generally provided with end electrodes 140. In particular, the end electrodes 140 are provided on the side surfaces 100C of the solid-state battery 100. More specifically, a positive end electrode 140A connected to the positive electrode layer 110 and a negative end electrode 140B connected to the negative electrode layer 120 are provided (see FIG. 1). Such end electrodes preferably contain a material with high conductivity. Specific materials for the end electrodes are not particularly limited, but may include at least one selected from the group consisting of silver, gold, platinum, aluminum, copper, tin, and nickel.

[0042] [Basic Configuration of Packaged Solid-State Battery] The present disclosure relates to a packaged solid-state battery, that is, a packaged solid-state battery having a configuration that includes a mountable substrate and protects the solid-state battery from the external environment.

[0043] 2 is a cross-sectional view schematically illustrating the configuration of a packaged solid-state battery according to an embodiment of the present disclosure. As illustrated, the packaged solid-state battery 1000 according to an embodiment of the present disclosure includes a substrate 200 for supporting the solid-state battery 100. Specifically, the packaged solid-state battery 1000 includes the mountable substrate 200 and the solid-state battery 100 that is provided on the substrate 200 and protected from the external environment.

[0044] As shown in FIG. 2 , the substrate 200 has a main surface larger than, for example, the solid-state battery. The substrate 200 may be a resin substrate or a ceramic substrate. In short, the substrate 200 may be a printed wiring board, a flexible substrate, an LTCC substrate, an HTCC substrate, or the like. When the substrate 200 is a resin substrate, the substrate 200 may be configured to contain a resin as a base material, for example, a substrate having a laminate structure including a resin layer. The resin material of such a resin layer may be any thermoplastic resin and / or any thermosetting resin. Furthermore, the resin layer may be configured, for example, by impregnating glass fiber cloth with a resin material such as epoxy resin.

[0045] The substrate preferably serves as a component for the external terminals of the packaged solid-state battery. In other words, it can be said that the substrate serves as a terminal substrate for the external terminals of the solid-state battery. A packaged solid-state battery equipped with such a substrate can be mounted on another secondary substrate such as a printed wiring board with the substrate interposed therebetween. For example, the solid-state battery can be surface-mounted via the substrate through solder reflow or the like. For this reason, the packaged solid-state battery of the present disclosure is preferably an SMD (Surface Mount Device) type battery package.

[0046] Such a substrate can be provided to support a solid-state battery, and can therefore also be considered a support substrate. Furthermore, since the substrate is a terminal substrate, it preferably has wiring or an electrode layer, and in particular, it is preferable that the substrate has an electrode layer that electrically connects the upper and lower surfaces or the upper and lower surface layers. In a preferred embodiment, the substrate has wiring or an electrode layer that electrically connects the upper and lower surfaces of the substrate, and serves as a terminal substrate for the external terminals of a packaged solid-state battery. In this embodiment, the wiring of the substrate can be used to connect the solid-state battery to the external terminals, eliminating the need to pack the battery in an exterior part described below and then connect the battery to the exterior of the exterior part, thereby increasing the degree of freedom in designing the external terminals.

[0047] A substrate 200 according to a preferred embodiment includes electrode layers (an upper principal surface electrode layer 210 and a lower principal surface electrode layer 220) that electrically connect the upper and lower principal surfaces of the substrate, and serves as a component for the external terminals of a packaged solid-state battery (see FIG. 2 ). In a packaged solid-state battery including such a substrate, the electrode layers of the substrate and the terminal portions of the solid-state battery are connected to each other. Preferably, the electrode layers of the substrate and the end electrodes of the solid-state battery are electrically connected to each other. For example, the end electrode 140A on the positive electrode side of the solid-state battery is electrically connected to the electrode layer (210A, 220A) on the positive electrode side of the substrate. Meanwhile, the end electrode 140B on the negative electrode side of the solid-state battery is electrically connected to the electrode layer (210B, 220B) on the negative electrode side of the substrate. As a result, the electrode layers on the positive electrode side and the electrode layer (particularly, the electrode layers located on the lower / bottom side of the packaged product, or the lands connected thereto) of the substrate serve as the positive and negative terminals of the packaged solid-state battery, respectively.

[0048] 2 , in order to enable electrical connection between the solid state battery 100 and the substrate electrode layer 210 of the substrate 200, the end surface electrode 140 of the solid state battery 100 and the substrate electrode layer 210 of the substrate 200 can be connected via a bonding member 600. This bonding member 600 at least serves to electrically connect the end surface electrode 140 of the solid state battery 100 and the substrate 200, and may include, for example, a conductive adhesive. As an example, the bonding member 600 may be made of an epoxy-based conductive adhesive containing a metal filler such as Ag.

[0049] Furthermore, in an embodiment of the present disclosure, not only the substrate 200 but also the packaged solid-state battery 1000 itself may be configured to prevent water vapor permeation as a whole. For example, the solid-state battery package 1000 according to an embodiment of the present disclosure may be covered with an exterior part 150 so that the solid-state battery 100 provided on the substrate 200 is entirely enclosed. In other words, the term "exterior part" in this specification refers to a covering member that surrounds the solid-state battery 100 on the substrate 200, and the "exterior part" may also be referred to as a "covering part" or a "packaging part." Specifically, the solid-state battery 100 on the substrate 200 may be packaged so that the main surface 100A and the side surface 100C are enclosed by the exterior part 150. With this configuration, all surfaces constituting the solid-state battery 100 are not exposed to the outside, thereby effectively preventing water vapor permeation (i.e., intrusion of water vapor into the solid-state battery).

[0050] In this specification, "water vapor" is not limited to gaseous water, but also includes liquid water. In other words, the term "water vapor" is used to broadly encompass gaseous water, liquid water, and the like, regardless of the physical state. Therefore, "water vapor" can also be referred to as moisture, and liquid water in particular can include condensed water formed by condensation of gaseous water. Since the intrusion of water vapor into a solid-state battery can cause deterioration of battery characteristics, the above-described packaged solid-state battery configuration contributes to extending the battery characteristics and life of the solid-state battery.

[0051] For example, as shown in FIG. 2 , the exterior part 150 may be composed of a coating insulating layer 160 and a coating inorganic layer 170. The solid-state battery 100 may have a configuration in which the exterior part 150 is covered with the coating insulating layer 160 and the coating inorganic layer 170. The coating inorganic layer 170 is provided to cover the coating insulating layer 160. Since the coating inorganic layer 170 is positioned on the coating insulating layer 160, it has a configuration in which, together with the coating insulating layer 160, it largely envelops the solid-state battery 100 on the substrate 200 as a whole. Furthermore, the coating inorganic layer 170 may also cover the side surface 250 of the substrate 200. The coating insulating layer 160 forms a suitable water vapor barrier in cooperation with the coating inorganic layer 170, and the coating inorganic layer 170 also forms a suitable water vapor barrier in cooperation with the coating insulating layer 160. Note that the coating insulating layer 160 may extend onto the side surface 250 of the substrate. In other words, the covering insulating layer 160 covering the top surface region 100B and the side surface region 100C of the solid-state battery also covers the side surface 250 of the substrate, and the covering inorganic layer 170 may be provided on such covering insulating layer 160.

[0052] The material of the covering insulating layer may be any type as long as it exhibits insulating properties. For example, the covering insulating layer may contain a resin, and the resin may be either a thermosetting resin or a thermoplastic resin. The covering insulating layer may contain an inorganic filler. As just one example, the covering insulating layer may be made of an epoxy-based resin containing an inorganic filler such as SiC.

[0053] The material of the coated inorganic layer is not particularly limited and may be metal, glass, oxide ceramic, or a mixture thereof. The coated inorganic layer may correspond to an inorganic layer having a thin film form, such as a metal film. For example, the coated inorganic layer may be a plating film containing at least one selected from the group consisting of Cu (copper), Sn (tin), Zn (zinc), Bi (bismuth), Au (gold), Ag (silver), Ni (nickel), Cr (chromium), Pd (palladium), and Pt (platinum) as a main component. In a preferred embodiment, the coated inorganic layer is composed of a Cu-based and / or Ni-based material plated to a thickness of 2 μm to 50 μm.

[0054] [Features of the Packaged Solid-State Battery of the Present Disclosure] The inventors of the present application have conducted extensive research into solutions for reducing the risk of damage to the end electrodes 140 due to expansion and contraction of the solid-state battery 100 associated with charging and discharging in the packaged solid-state battery 1000 described above, and as a result have devised the present invention having the following technical idea.

[0055] The present disclosure has the technical idea of ​​"a structure including a gap between the end electrode and the exterior portion." More specifically, the present disclosure has the technical idea of ​​"a structure including a gap between the end electrode and the exterior portion, with the end electrode and the exterior portion separated by the gap."

[0056] To realize the above technical idea, the present disclosure has the following technical features. As shown in FIG. 2 , a solid-state battery 100 disposed on a substrate 200 includes an end electrode 140 provided on a side surface 100C of the solid-state battery 100. An exterior portion 150 is provided to surround the solid-state battery 100 on the substrate 200 together with the end electrode 140. FIG. 3 is an enlarged cross-sectional view schematically illustrating part A, which is a part of the boundary region between the end electrode 140 and the exterior portion 150, in the packaged solid-state battery 1000 shown in FIG. 2 . As shown in FIGS. 2 and 3 , a gap 180 is included between the end electrode 140 and the exterior portion 150. In other words, the end electrode 140 and the exterior portion 150 may face each other with the gap 180 interposed therebetween. In other words, the exterior portion 150 may be provided to cover the solid-state battery 100, with a gap formed between the end electrode 140 and the exterior portion 150 via the gap 180.

[0057] In such a configuration, the end electrode 140 and the exterior part 150 may be separated by a gap 180. That is, the packaged solid-state battery of the present disclosure includes a portion where the solid-state battery 100 and the exterior part 150 face each other at a distance, and a portion where the solid-state battery 100 and the exterior part 150 contact each other. In such a configuration, the portion where the solid-state battery 100 faces each other at a distance may be located between the end electrode 140 and the exterior part 150. In short, the packaged solid-state battery of the present disclosure includes a portion where the end electrode 140 and the exterior part 150 face each other at a distance. This means that the exterior part 150 can be provided to cover the solid-state battery with the end electrode while being at least partially separated from the end electrode 140.

[0058] The solid-state battery 100 covered by the exterior part 150 has a first main surface 100A facing the substrate 200 and a second main surface 100B facing the first main surface 100A. In other words, assuming a typical solid-state battery having two opposing main surfaces, the second main surface 100B facing the substrate 200 is the main surface on the mounting side in an SMD type, and may also be referred to as the "bottom surface" or "lower surface." The second main surface 100B refers to the main surface located opposite the first main surface 100A, and may also be referred to as the "top surface," "top surface," or "upper surface."

[0059] Furthermore, the term "side surface of the solid-state battery" refers to a surface connecting the first principal surface 100A and the second principal surface 100B. In one embodiment of the present disclosure, an end surface electrode 140 may be provided on each of two opposing side surfaces 100C of the solid-state battery 100. Specifically, as shown in FIG. 1 , the positive electrode end surface electrode 140A connected to the positive electrode layer 110 and the negative electrode end surface electrode 140B connected to the negative electrode layer 120 may be disposed on the two opposing side surfaces 100C. In the present disclosure, the void 180 may be provided in at least one of the positive electrode end surface electrode 140A and the negative electrode end surface electrode 140B. In other words, the exterior part 150 may cover the solid-state battery, including a portion facing and spaced from at least one of the positive electrode end surface electrode 140A and the negative electrode end surface electrode 140B.

[0060] As described above, the exterior part 150 may include the covering insulating layer 160. In a preferred embodiment, the covering insulating layer 160 is provided to cover the solid state battery 100, and the covering inorganic layer 170 is provided on the covering insulating layer 160. In this embodiment, the end surface electrode 140 may include a gap 180 between itself and the covering insulating layer 160. In other words, the end surface electrode 140 and the covering insulating layer 160 may face each other and be spaced apart from each other via the gap 180.

[0061] A force pulling the end electrode 140 in the expansion / contraction direction of the solid-state battery 100 may act on the end electrode 140. When the solid-state battery 100 expands and contracts in the stacking direction of the electrode layers, the expansion / contraction direction is the same as the extension direction of the end electrode 140 (see FIG. 1 ). That is, the expansion / contraction direction can also be interpreted as the same as the extension direction of the side surface 100C of the solid-state battery. The end electrode 140 is joined to the solid-state battery 100 at the side surface 100C of the solid-state battery. Meanwhile, the exterior part 150 is disposed on the solid-state battery 100 via the end electrode 140 in the region covering the end electrode 140. Compared to the end electrode 140 being in physical contact with the solid-state battery 100, the force acting in the extension direction of the end electrode 140 due to the expansion / contraction of the solid-state battery is less likely to propagate to the exterior part 150. Therefore, the exterior part 150 may be less able to follow the expansion / contraction of the solid-state battery 100.

[0062] As such, the exterior part 150 may be less able to follow the expansion and contraction of the solid-state battery 100 than the end electrode 140. Therefore, when the end electrode 140 and the exterior part 150 are joined to each other, the exterior part 150 restrains the end electrode 140 at the joint surface with the end electrode 140 (i.e., the outer surface 145 of the end electrode), and can suppress deformation of the end electrode 140 that follows the expansion and contraction of the solid-state battery 100. As a result, when the solid-state battery 100 expands and contracts, the outer surface 145 of the end electrode 140 is less likely to deform due to the restraint by the exterior part 150, whereas the inner surface of the end electrode 140, which is physically joined to the solid-state battery 100, is more likely to deform in response to the expansion and contraction. As a result, the difference in ease of deformation between the inner surface of the end electrode 140 and the outer surface 145 of the end electrode joined to the exterior part 150 may cause distortion inside the end electrode 140, which may result in damage to the end electrode 140.

[0063] According to the configuration of the present disclosure, the outer surface 145 of the end electrode located on the exterior part 150 side has a portion separated from the exterior part 150 by a gap 180. Therefore, in this separated portion, the outer surface of the end electrode is not constrained by the exterior part 150. In other words, by providing the gap 180 between the end electrode 140 and the exterior part 150, the constraint on the outside of the end electrode 140 by the exterior part 150 can be alleviated as a whole. Therefore, when the end electrode 140 deforms due to volumetric changes such as expansion and contraction of the solid-state battery 100, the influence of the constraint by the exterior part 150 can be reduced. This suppresses distortion within the end electrode 140 caused by expansion and contraction of the solid-state battery 100, thereby reducing the risk of damage to the end electrode 140. Furthermore, reducing this distortion can also reduce fatigue of the end electrode 140 caused by repeated expansion and contraction of the solid-state battery 100. This suppresses deterioration, peeling, and the like of the end electrode 140, thereby improving the long-term reliability of the packaged solid-state battery.

[0064] 2 , the exterior part 150 is in physical contact with the second main surface 100B of the solid-state battery. Therefore, when the solid-state battery 100 expands and contracts in the stacking direction of the electrode layers, the exterior part 150 located on the second main surface 100B of the solid-state battery can suitably follow and deform in the expansion and contraction direction of the solid-state battery 100. Furthermore, the exterior part 150 is also bonded to the substrate 200 on which the solid-state battery 100 is disposed. This bonding can help to suitably hold the exterior part 150 on the solid-state battery 100. Therefore, even in the embodiment in which the gap 180 is formed between the end electrode 140 and the exterior part 150 as described above, the exterior part 150 can be suitably held on the solid-state battery 100 without being easily damaged and / or peeled off due to deformation accompanying the expansion and contraction of the solid-state battery.

[0065] The end electrode 140 and the exterior portion 150 do not necessarily need to be completely separated from each other. In other words, the end electrode 140 may be in partial contact with the exterior portion 150. In one embodiment, the end electrode 140 includes a non-contact portion 145A and a contact portion 145B with the exterior portion 150 (see FIG. 4 ). With this configuration, the contact portion 145B can help support the exterior portion 150 on the end electrode 140. For example, even if stress is applied near the void portion 180, the contact portion 145B can effectively distribute the stress to the end electrode 140 and / or the exterior portion 150, preventing damage to the end electrode 140 and the exterior portion 150. Supporting the exterior portion 150 on the end electrode 140 by the contact portion 145B can improve the overall strength of the exterior portion 150. Furthermore, at the contact portion 145B, the end electrode 140 can be sandwiched on the solid-state battery 100 by the exterior part 150. The contact portion 145B between the end electrode 140 and the exterior part 150 can suitably hold the end electrode 140 on the solid-state battery and can help prevent the end electrode 140 from peeling off from the solid-state battery.

[0066] For example, the contact portion between the end electrode 140 and the exterior part 150 may be at least the end 141 of the end electrode 140. Specifically, the end electrode 140 may be in contact with the exterior part 150 at at least one of the substrate-side end 141a located on the first main surface 100A side of the solid-state battery and the top-side end 141b located on the second main surface 100B side. The "top-side end" and "bottom-side end" correspond to the end 141 located distally from the substrate 200 and the end 141 located proximal to the substrate 200, respectively, of the end electrode 140. In other words, the contact portion between the end electrode 140 and the exterior part 150 may be located at the end 141 of the end electrode located on the second main surface 100B side and / or the substrate 200 side of the solid-state battery.

[0067] As described above, the exterior part 150 has a contact portion with the end part 141 of the end electrode, so that the joint between the end part 141 of the end electrode and the solid-state battery 100 is covered by the exterior part 150. With this structure, the end part 141 of the end electrode can be suitably sandwiched between the solid-state battery by the exterior part 150. Therefore, it is possible to suitably prevent the end electrode from peeling off from the solid-state battery due to expansion and contraction of the solid-state battery 100. Furthermore, since the exterior part 150 covers the joint between the end part 141 of the end electrode and the solid-state battery 100, it is possible to suitably prevent water vapor from penetrating into the solid-state battery 100 through the connection between the end part 141 of the end electrode and the solid-state battery 100. In other words, the present disclosure provides a packaged solid-state battery that simultaneously reduces the risk of damage to the end electrode due to expansion and contraction and prevents water vapor from penetrating into the solid-state battery.

[0068] FIG. 5 is a cross-sectional view schematically illustrating a packaged solid-state battery according to another embodiment. In one embodiment, the end electrode 140 may extend to at least one of the first main surface 100A and the second main surface 100B of the solid-state battery. That is, the end 141 of the end electrode may extend to at least one of the first main surface 100A and the second main surface 100B of the solid-state battery. With this structure, the end electrode extends to the first main surface 100A, thereby increasing the bonding area between the end electrode 140 and the bonding member 600. Therefore, the above-described structure can contribute to improving the connection reliability between the end electrode 140 and the bonding member 600.

[0069] The exterior portion 150 may be in contact with the edge electrode 140 at an end 141 of the edge electrode located on the first principal surface 100A and / or the second principal surface 100B. In other words, the contact portion between the exterior portion 150 and the edge electrode 140 may be located at the end 141 of the edge electrode extending on the first principal surface 100A and / or the second principal surface 100B.

[0070] With this structure, the end electrode 140 can extend along the side surface 100C and the first and / or second main surfaces 100A and 100B of the solid-state battery. This increases the bonding area between the end electrode 140 and the solid-state battery 100, effectively preventing peeling of the end electrode due to volumetric changes in the solid-state battery. Furthermore, the end electrode 140 is bonded to the exterior part 150 at the end 141 of the end electrode extending onto the first and / or second main surfaces 100A and 100B, effectively sandwiching the end electrode 140 between the exterior part 150 and the solid-state battery 100. This effectively prevents peeling of the end electrode from the solid-state battery due to expansion and contraction of the solid-state battery.

[0071] 4 is an enlarged cross-sectional view schematically illustrating a boundary region between an end electrode 140 and an exterior part 150 according to another embodiment of the present disclosure. As illustrated, the packaged solid-state battery may include a plurality of voids 180. The plurality of voids 180 may be formed intermittently along the end electrode 140. In other words, the end electrode 140 may be provided with a plurality of contact portions 145B and a plurality of non-contact portions 145A with the exterior part 150, thereby forming a plurality of voids 180 intermittently.

[0072] In this specification, the term "intermittently formed voids" does not necessarily mean that the plurality of voids 180 are formed independently of each other. For example, the plurality of voids 180 may be in a state in which adjacent voids 180 are partially connected to each other in a cross-sectional view. This means that the inner surface 155 of the exterior part facing the end electrode 140 may be a surface including projections and depressions in a cross-sectional view. For example, contact portions 145B and non-contact portions 145A between the end electrode 140 and the exterior part 150 may be alternately and repeatedly provided. In such a structure, the plurality of voids 180 may be provided irregularly or substantially regularly along the end electrode.

[0073] In this way, when a packaged solid-state battery includes multiple intermittent voids 180, providing non-contact portions 145A at multiple locations on the end electrode 140, where the end electrode 140 is not constrained by the exterior housing 150, can prevent localization of the unconstrained and constrained portions of the end electrode. Therefore, distortions occurring in the end electrode due to expansion and contraction of the solid-state battery are more effectively alleviated overall, and the risk of damage to the end electrode can be suitably reduced. Furthermore, by providing contact portions 145B at multiple locations while maintaining the non-contact portions 145A, the non-contact portions 145A suppress distortion in the end electrode 145, and the contact portions 145B suitably hold the end electrode 145 to the solid-state battery 100.

[0074] In a preferred embodiment, the void 180 has an elongated shape extending along the end electrode 140 in a cross-sectional view. In other words, the cross-sectional shape of the void 180 may be elongated or flat along the extension direction of the end electrode 140. Furthermore, in an embodiment having multiple voids 180, the cross-sectional shapes of the voids 180 do not necessarily have to be the same, and may be different from one another. For example, the cross-sectional shapes of the multiple voids 180 may be elongated shapes with different dimensions from one another.

[0075] The void 180, which has an elongated cross-sectional shape, may extend along the principal surface region 143 of the end electrode. In a preferred embodiment, the void 180 has an elongated cross-sectional shape extending along the outer surface 145 of the principal surface region 143 of the end electrode. In this specification, the "principal surface region of the end electrode" refers to the region of the end electrode 140 located on the side surface 100C of the solid-state battery. In other words, the void 180 may be located on the end electrode 140 located on the side surface 100C of the solid-state battery. With this structure, the end electrode 140 is separated from the exterior part 150 over a wider area, which can more effectively alleviate the constraint of the end electrode 140 by the exterior part 150. This allows the end electrode to more effectively follow volumetric changes of the solid-state battery, suppressing distortion that may occur in the end electrode and reducing the risk of damage to the end electrode.

[0076] Furthermore, the cross-sectional shape of the void 180 may correspond to the cross-sectional shape of the outer surface 145 of the end electrode. Specifically, in a cross-sectional view, the void 180 may have a shape corresponding to the cross-sectional shape of the outer contour forming surface of the end electrode 140. For example, as shown in FIG. 6 , if the outer surface 145 of the end electrode has a curved cross-sectional shape, the void 180 may have an elongated cross-sectional shape that curves along the curved portion. With this structure, in a cross-sectional view, the void 180 may extend along the outer surface 145 of the end electrode so as to have a constant width. In other words, the end electrode 140 and the exterior part 150 may include portions that face each other with a constant gap between them. This more effectively reduces the restraining force of the exterior part 150 on the end electrode 140, so that even if deformation occurs in the end electrode 140 due to expansion and contraction of the solid-state battery 100, excessive distortion does not occur inside the end electrode 140, and the risk of damage to the end electrode 140 can be reduced.

[0077] In one embodiment, the void 180 may be continuous across the entire principal surface region 143 of the end electrode. In other words, the end electrode 140 may be spaced apart and face the exterior housing 150 across the entire principal surface region 143. In such an embodiment, the void 180 may have an elongated cross-sectional shape extending across the principal surface region 143 of the end electrode, as shown in FIGS. 2 and 5 . Although not shown, the void 180 may be continuous not only in the plan view direction but also in the cross-sectional view direction. That is, the void 180 may be two-dimensionally continuous across the principal surface region 143 of the end electrode. This structure more effectively alleviates the constraint on the end electrode by the exterior housing, allowing the end electrode to more effectively follow volumetric changes in the solid-state battery. Therefore, the present disclosure provides a more suitable packaged solid-state battery that reduces strain that may occur in the end electrode and reduces the risk of damage to the end electrode due to volumetric changes in the solid-state battery.

[0078] In a cross-sectional view, the width W of the void 180 may be 1 μm to 50 μm, 1 μm to 30 μm, or 1 μm to 25 μm, for example, 2 μm to 10 μm (see FIG. 3 ). Here, the width W of the void can also be interpreted as the distance by which the end electrode 140 and the exterior part 150 are separated and opposed by the void 180. Note that the width W of the void can be appropriately changed depending on the size of the solid-state battery, the thickness of the end electrode, the thickness of the exterior part, and the like. For example, as shown in FIG. 4 , multiple voids 180 may have different widths.

[0079] Furthermore, in a cross-sectional view, the non-contact portion 145A between the exterior portion 150 and the end electrode 140 may be larger than the contact portion 145B (see FIG. 4 ). That is, the contact ratio between the exterior portion 150 and the end electrode 140 may be less than 50%. In other words, the non-contact portion 145A may occupy 50% or more of the outer surface 145 of the end electrode. For example, in a cross-sectional view, the proportion of the non-contact portion 145A relative to the length of the outer surface of the end electrode may be 50% to 100%, 60% to 99%, or 65% to 99%, for example, 70% to 95%. When the proportion of the non-contact portion 145A relative to the total length of the outer surface 145 of the end electrode in the cross-sectional view is within the above-mentioned range, the end electrode can suitably follow the expansion and contraction of the solid-state battery, thereby reducing the risk of breakage of the end electrode due to volumetric changes of the solid-state battery.

[0080] 5 , the end electrode 140 may be provided so as to cover a corner of the solid-state battery. In this specification, the term "corner of the solid-state battery" refers to a corner between the main surface 100A or 100B and the side surface 100C of the solid-state battery, and includes both an apex corner where the main surface 100A or 100B intersects with the two side surfaces 100C, and a corner between the main surface 100A or 100B and the side surface 100C. Specifically, the solid-state battery 100 has a first corner 102a located proximal to the substrate 200 and a second corner 102b located distal to the substrate 200, and the end electrode 140 may be provided so as to cover at least one of the first corner 102a and the second corner 102b. In this embodiment, the end surface electrode 140 covering the first corner 102a can be referred to as a first corner covering region 142a, and the end surface electrode 140 covering the second corner 102b can be referred to as a second corner covering region 142b.

[0081] FIG. 6 is an enlarged cross-sectional view schematically illustrating portion B, which is the connection portion between the end electrode 140 and the bonding member, in the packaged solid-state battery 1000 shown in FIG. 5 . In cross-sectional view, the thickness Ta of the first corner covering region 142a may be greater than the thickness of other regions other than the first corner covering region 142a. Here, the thickness of the corner covering region refers to the thickness of the end electrode 140 in the extension direction of the main surface of the solid-state battery. Specifically, it refers to the distance from the contact point between the corner of the solid-state battery covered by the corner covering region and the inner surface of the end electrode 140 to the intersection point between an extension of the main surface of the solid-state battery and the outer surface 145 of the end electrode. As shown in FIG. 6 , in cross-sectional view, the end electrode 140 covering the first corner 102a may have a greater thickness than other regions. In other words, in cross-sectional view, the end electrode 140 may be configured so that it is relatively thicker in the first corner covering region 142a.

[0082] Of the stresses caused by expansion and contraction of the solid-state battery 100, the stress acting from the solid-state battery 100 side to the substrate 200 side may increase as it moves from the solid-state battery 100 to the end electrode 140 side. That is, of the stresses acting from the solid-state battery 100 side to the substrate 200 side, the stress along the end electrode 140 may be relatively the largest. In particular, the first corner covering region 142a covering the first corner 102a located on the substrate 200 side may be subjected to greater stress, which may cause damage. In the present disclosure, by providing an end electrode having a relatively greater thickness in the first corner covering region 142a as described above, a packaged solid-state battery with improved connection reliability of the end electrode can be provided.

[0083] More specifically, in a cross-sectional view, the thickness Ta of the first corner covering region 142a of the end electrode may be greater than the thickness Tb (see FIG. 5 ) of the second corner covering region 142b located distally from the substrate 200. As described above, stress due to expansion and contraction of the solid-state battery may be greater at the first corner 102a located proximal to the connection point with the substrate 200 than at the second corner 102b located on the second main surface 100B of the solid-state battery. Therefore, in a cross-sectional view, the first corner covering region 142a may have a greater thickness than the second corner covering region 142b. This structure can provide a packaged solid-state battery with a reduced risk of damage to the end electrode in the corner covering region.

[0084] In a cross-sectional view, the ratio of the thickness Ta of the first corner covering region 142a to the thickness Tb of the second corner covering region 142b of the end electrode may be 101% to 500%, 200% to 400%, or 280% to 370%, for example, 300% to 350%. When the thickness Ta of the first corner covering region 142a of the end electrode in a cross-sectional view is within the above range, a packaged solid-state battery with improved connection reliability of the end electrode can be provided.

[0085] Furthermore, in a cross-sectional view, the thickness Ta of the end electrode 140 in the first corner covering region 142a may be greater than the thickness Tc of the end electrode 140 in the main surface region 143 located on the side surface 100C of the solid-state battery. In a preferred embodiment, in a cross-sectional view, the thickness of the end electrode 140 may gradually increase from the region of the main surface region facing the substrate 200 toward the first corner covering region 142a, as shown in Figures 5 and 6. This structure can provide a packaged solid-state battery with a reduced risk of breakage of the end electrode in the corner covering region.

[0086] The structure of the packaged solid-state battery of this specification may be observed from an image obtained by cutting out a cross section in the cross-sectional viewing direction using an ion milling device (manufactured by Hitachi High-Tech Corporation, model number SU-8040) and acquiring the cross section using a scanning electron microscope (SEM) (manufactured by Hitachi High-Tech Corporation, model number SU-8040). Furthermore, the dimensions of the voids and end electrodes referred to in this specification may refer to values ​​calculated from the dimensions measured from the image acquired by the above-mentioned method.

[0087] [Method for Manufacturing Packaged Solid-State Battery] The subject matter of the present disclosure 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 (see FIGS. 7A to 7E).

[0088] The production of the solid-state battery of the present disclosure can be broadly divided into the production of the solid-state battery itself (hereinafter also referred to as a "pre-packaged battery"), which corresponds to a stage before packaging, the preparation of the substrate, and packaging.

[0089] <<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).

[0090] In the following, one manufacturing method will be described as an example for better understanding of the present disclosure, but the present disclosure is not limited to this method. Furthermore, the chronological order of the following description is merely for the convenience of explanation and is not necessarily binding.

[0091] (Laminate Block Formation) A solid electrolyte, an organic binder, a solvent, and optional additives are mixed to prepare a slurry. The prepared slurry is then fired to form a sheet containing the solid electrolyte. A positive electrode paste is prepared by mixing a positive electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and optional additives. Similarly, a negative electrode paste is prepared by mixing a negative electrode active material, a solid electrolyte, a conductive material, an organic binder, a solvent, and optional additives. The positive electrode paste is printed on a sheet, and a current collecting layer and / or a negative layer are printed as needed. Similarly, a negative electrode paste is printed on a sheet, and a current collecting layer and / or a negative layer are printed as needed. Sheets printed with the positive electrode paste and sheets printed with the negative electrode paste are alternately stacked 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.

[0092] (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. In this way, a fired laminate is obtained. Note that the laminate may be degreased and fired before cutting, and then cut.

[0093] (Formation of End Electrodes) The positive end electrode 140A can be formed by applying a conductive paste to the exposed positive electrode side of the fired laminate. Similarly, the negative end electrode 140B can be formed by applying a conductive paste to the exposed negative electrode side of the fired laminate. As shown in FIG. 7A , the positive and negative end electrodes 140 may be provided so as to extend to the main surfaces of the fired laminate. The components of the end electrodes may be at least one selected from silver, gold, platinum, aluminum, copper, tin, and nickel.

[0094] The positive and negative end electrodes 140 do not necessarily have to be formed after firing of the laminate, but may be formed before firing and then subjected to simultaneous firing.

[0095] By going through the steps described above, a desired pre-packaged battery (corresponding to the solid-state battery 100 shown in FIG. 7A) can finally be obtained.

[0096] (Gap Forming Treatment) Next, the outer surface 145 of the end electrode may be treated to form a gap between the end electrode 140 and the exterior portion. The gap between the end electrode 140 and the exterior portion may be formed by applying a gap-forming agent 190 before the exterior portion is formed (see FIG. 7B ). For example, after the end electrode 140 is formed, the gap-forming agent 190 for forming the gap may be applied to the end electrode 140. The gap-forming agent 190 need only be applied to the portions of the end electrode 140 where the gap is to be formed. For example, the gap-forming agent 190 may be applied over the entire end electrode 140, or may be applied only to a partial region of the end electrode, such as the main surface region 143 of the end electrode located on the side of the solid-state battery (see FIG. 5 ).

[0097] Examples of the void-forming agent used may include known materials that vaporize near the heating temperature during molding to form the covering insulating layer 160 (see FIG. 7C ), which will be described later. Any material may be selected as the void-forming agent depending on the conditions for forming the covering insulating layer (e.g., heating temperature, etc.). While merely illustrative, examples of such void-forming agents include wax-based materials such as paraffin wax and microcrystalline wax. When such a void-forming agent is used, the void-forming agent vaporizes during heating during molding to form the covering insulating layer, penetrates into the covering insulating layer, and is lost, resulting in the formation of a void between the end electrode 140 and the covering insulating layer.

[0098] The gap-forming agent may be a material that reduces the adhesion between the end electrode 140 and the exterior portion. For example, the gap-forming agent may be a known material that improves the releasability of the exterior portion provided on the end electrode 140 from the end electrode. While merely illustrative, examples of such gap-forming agents include fluorine-based materials, silicone-based materials, and wax-based materials. When such a gap-forming agent is used, the exterior portion separates from the end electrode 140 at the location where the gap-forming agent is applied, forming a gap between the end electrode 140 and the exterior portion.

[0099] Alternatively, the void-forming agent may be a foaming material such as a foaming resin. The foaming resin may be a resin that foams to form a foam during molding of the exterior portion. The foaming resin is not particularly limited, and known foaming resins used in resin foam molding can be used. For example, the foaming material may be a thermoplastic resin blended with at least one of a chemical foaming agent and foam beads. Note that, although it is preferable that no void-forming agent as described above remains in the final packaged solid-state battery, the packaged solid-state battery may contain a void-forming agent.

[0100] <Preparation of Substrate> In this step, a substrate is prepared.

[0101] 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 raw 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.

[0102] By going through the above steps, the desired substrate 200 can finally be obtained.

[0103] <<Packaging>> Next, the battery and substrate obtained above are packaged (see FIGS. 7C to 7E).

[0104] First, the pre-packaged battery 100 is placed on the substrate 200. That is, an "unpackaged solid-state battery" is placed on the substrate (hereinafter, a battery used for packaging will also be simply referred to as a "solid-state battery").

[0105] Preferably, the solid-state battery 100 is placed on the substrate so that the conductive portions of the substrate and the end electrodes 140 of the solid-state battery 100 are electrically connected to each other. For example, a conductive paste may be applied to the substrate, thereby electrically connecting the conductive portions of the substrate and the end electrodes 140 of the solid-state battery 100 to each other. More specifically, the conductive portions (particularly the lower lands / bottom lands) on the positive and negative sides of the main surface of the substrate are aligned with the positive and negative end electrodes 140 of the solid-state battery 100, respectively, and then bonded using a conductive paste (e.g., Ag conductive paste). In other words, a precursor of a bonding member that provides electrical connection between the solid-state battery 100 and the substrate may be provided on the substrate in advance.

[0106] The precursor of such a bonding member can be provided by printing a conductive paste that does not require washing with flux or the like after formation, such as Ag conductive paste, nanopaste, alloy paste, brazing material, etc. Next, the solid-state battery 100 is placed on the substrate so that the end surface electrode 140 and the precursor of the bonding member are in contact with each other, and by subjecting the precursor to a heat treatment, a bonding member that contributes to electrical connection between the solid-state battery 100 and the substrate is formed from the precursor.

[0107] Next, the exterior part 150 is formed. The exterior part 150 may include a coating insulating layer 160 and a coating inorganic layer 170.

[0108] First, the covering insulating layer 160 is formed to cover the solid-state battery 100 on the substrate 200 (see FIG. 7C ). Therefore, a raw material for the covering insulating layer is provided so as to completely cover the solid-state battery 100 on the substrate. When the covering insulating layer is made of a resin material, a resin precursor is applied to the substrate and cured to form the covering insulating layer. In a preferred embodiment, the covering insulating layer may be formed by applying pressure using a mold. By way of example only, the covering insulating layer that seals the solid-state battery 100 on the substrate may be formed using a compression mold. If the covering insulating layer is made of a resin material typically used in molding, the raw material for the covering insulating layer may be in the form of granules or may be thermoplastic. This molding is not limited to mold molding, and may also be performed using polishing, laser processing, and / or chemical treatment.

[0109] During the molding process of the covering insulating layer 160, the gap-forming agent 190 applied to the end electrode 140 as described above forms a gap 180 between the end electrode 140 and the covering insulating layer 160 (see FIG. 7D ). For example, the gap 180 may be formed by vaporizing and disappearing the gap-forming agent due to heating during the molding process of the covering insulating layer 160.

[0110] After forming the covering insulating layer 160, the covering inorganic layer 170 is formed (see FIG. 7E ). The covering inorganic layer 170 may be formed by plating the covering precursor. In one embodiment, the covering inorganic layer is formed on the covering precursor by forming a plating film on an exposed surface other than the bottom surface of the covering precursor (i.e., other than the bottom surface of the support substrate).

[0111] By going through the above steps, a packaged product having a gap between the end electrode and the exterior part can be obtained, that is, a "packaged solid-state battery" according to the present disclosure can be finally obtained.

[0112] Although not shown, the coating inorganic layer may extend to the bottom principal surface of the substrate located opposite the principal surface of the substrate facing the solid-state battery. That is, the coating insulating layer and / or the coating inorganic layer may extend to the side surface of the substrate as an exterior part and may extend beyond the side surface to the bottom principal surface of the substrate (particularly its peripheral portion). In this case, a packaged solid-state battery can be obtained that is more effectively prevented from infiltrating moisture from the outside into the solid-state battery.

[0113] The coated inorganic layer can also be provided as a multilayer structure consisting of at least two layers. Such a multilayer structure is not limited to between different materials, but may also be between the same materials. For example, the coated inorganic layer may have a multilayer structure in which two or more dry-plated films formed by dry plating and wet-plated films formed by wet plating are stacked in any order. Providing such a multilayer coated inorganic layer makes it easier to form a water vapor barrier for a solid-state battery.

[0114] The water vapor barrier layer may be formed on the substrate in advance, that is, before packaging in which the substrate and the solid-state battery are combined.

[0115] There are no particular limitations on the water vapor barrier layer, as long as it can form a desired barrier layer. For example, a "water vapor barrier layer having Si-O bonds and Si-N bonds" is preferably formed by applying a liquid precursor and irradiating it with ultraviolet light. In other words, the water vapor barrier layer is formed under relatively low temperature conditions (for example, a temperature condition of about 100°C) without using a vapor phase deposition method such as CVD or PVD.

[0116] Specifically, a liquid source containing, for example, silazane is prepared, and the liquid source is applied to a substrate by spin coating or spray coating, and then dried to form a barrier precursor. The barrier precursor is then exposed to UV light in a nitrogen-containing ambient atmosphere, thereby obtaining a water vapor barrier layer having Si—O bonds and Si—N bonds.

[0117] It is preferable to locally remove the water vapor barrier layer at the joining portion between the conductive portion of the substrate and the end electrode of the solid-state battery so that the water vapor barrier layer is not present at that portion. Alternatively, a mask may be used to prevent the water vapor barrier layer from being formed at the joining portion. That is, a mask may be applied to the joining portion, and the water vapor barrier layer may be formed overall, and then the mask may be removed.

[0118] Although the embodiments of the present disclosure have been described above, they are merely typical examples. Those skilled in the art will readily understand that the present disclosure is not limited thereto, and that various modifications are possible within the scope of the present disclosure.

[0119] Note that one embodiment of the present disclosure as described above includes the following preferred aspects. First Aspect: A packaged solid-state battery comprising a substrate, a solid-state battery with end electrodes provided on the substrate, and an exterior covering covering the solid-state battery, wherein the exterior covering contains resin and includes a void between the end electrodes and the exterior covering. Second Aspect: A packaged solid-state battery according to the first aspect, including a portion where the solid-state battery and the exterior covering face each other at a distance and a portion where the solid-state battery and the exterior covering contact each other, wherein the void is located between the end electrodes and the exterior covering. Third Aspect: A packaged solid-state battery according to the first or second aspect, wherein the void is located between the exterior covering and at least one of the end electrodes on the positive electrode side and the end electrodes on the negative electrode side. Fourth Aspect: A packaged solid-state battery according to any of the first to third aspects, wherein a plurality of the voids are formed intermittently along the end electrodes. Fifth Aspect: A packaged solid-state battery according to any one of the first to fourth aspects, wherein the end electrode includes a contact portion and a non-contact portion with the exterior part. Sixth Aspect: A packaged solid-state battery according to the fifth aspect, wherein the contact portion is located at at least one of a top surface side end of the end electrode located distal to the substrate and a substrate side end located proximal to the substrate. Seventh Aspect: A packaged solid-state battery according to the fifth or sixth aspect, wherein the solid-state battery comprises a first main surface facing the substrate and a second main surface located opposite to the first main surface, an end of the end electrode extends over at least one of the first main surface and the second main surface, and the contact portion is located at the end. Eighth Aspect: A packaged solid-state battery according to any one of the first to seventh aspects, wherein the gap has an elongated shape extending along the main surface region of the end electrode in a cross-sectional view. Ninth Aspect: In any one of the first to eighth aspects, the packaged solid-state battery is such that the void portion is continuous over the entire main surface area of ​​the end electrode.Aspect 10: A packaged solid-state battery according to any one of Aspects 1 to 9, wherein the exterior part includes an insulating coating layer covering the solid-state battery, and the end electrode and the insulating coating layer are spaced apart and opposed to each other with the gap therebetween. Aspect 11: A packaged solid-state battery according to any one of Aspects 1 to 10, wherein the cross-sectional shape of the gap corresponds to the cross-sectional shape of the outer surface of the end electrode. Aspect 12: A packaged solid-state battery according to any one of Aspects 1 to 11, wherein, in a cross-sectional view, the non-contact portion occupies 50% or more and 100% or less of the outer surface of the end electrode. Aspect 13: A packaged solid-state battery according to any one of Aspects 1 to 12, wherein the solid-state battery includes a first corner located proximal to the substrate, and the end electrode includes a first corner covering region covering the first corner, and, in a cross-sectional view, the thickness of the first corner covering region is greater than the thickness of other regions other than the first corner covering region. Aspect 14: A packaged solid-state battery according to the aspect 13, wherein the solid-state battery includes a second corner located distal to the substrate, the end electrode includes a second corner covering region covering the second corner, and the other region is the second corner covering region. Aspect 15: A packaged solid-state battery according to the aspect 12 or 13, wherein the other region is a main surface region of the end electrode.

[0120] The packaged solid-state batteries of the present disclosure can be utilized in a variety of fields where battery use or storage is envisioned. Although merely illustrative, the packaged solid-state battery of the present disclosure can be used in the electrical, information, and communications fields where mobile devices and the like are used (for example, the electrical and electronic equipment fields or mobile device fields including mobile phones, smartphones, laptop computers, digital cameras, activity monitors, arm computers, electronic paper, 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 (for medical devices such as earphone hearing aids), pharmaceutical applications (for example, medication management systems), as well as the IoT field, and space and deep-sea applications (for example, space probes, submersible research vessels, and the like).

[0121] 100 Solid-state battery 100A First main surface of solid-state battery 100B Second main surface of solid-state battery 100C Side surface of solid-state battery 102a First corner of solid-state battery 102b Second corner of solid-state battery 110 Positive electrode layer 120 Negative electrode layer 130 Solid electrolyte or solid electrolyte layer 140 End electrode 140A Positive electrode side end electrode 140B Negative electrode side end electrode 141a Top side end 141b Bottom side corner 142a First corner covering region 142b Second corner covering region 143 Main surface region of end electrode 145 Outer surface of end electrode 145A Non-contact portion 145B Contact portion 150 Exterior portion 155 Inner surface of exterior portion 160 Covering insulating layer 170 Covering inorganic layer 180 Void portion 190 Gap-forming agent 200 Substrate 210 Substrate electrode layer (upper side of substrate) 210A Positive electrode side substrate electrode layer 210B Negative electrode side substrate electrode layer 220 Mounting side substrate electrode layer (lower side of substrate) 220A Positive electrode side mounting side substrate electrode layer 220B Negative electrode side mounting side substrate electrode layer 250 Side surface of substrate 600 Bonding member 1000 Packaged solid-state battery

Claims

1. A solid-state battery having an end electrode provided on a substrate, and an exterior part covering the solid-state battery, the exterior portion includes a resin, A packaged solid-state battery comprising a gap between the end electrodes and the exterior.

2. a portion where the solid-state battery and the exterior part face each other with a space therebetween, and a portion where the solid-state battery and the exterior part come into contact with each other, 2. The packaged solid-state battery of claim 1, wherein the spaced apart and opposing portions are located between the end electrodes and the exterior housing.

3. 3. The packaged solid-state battery according to claim 1, wherein the gap is between the exterior part and at least one of the end electrode on the positive electrode side and the end electrode on the negative electrode side.

4. The packaged solid-state battery according to claim 1 , wherein the end electrodes include a contact portion and a non-contact portion with the exterior portion.

5. 5. The packaged solid-state battery of claim 4, wherein the contact portion is located on at least one of a top end of an edge electrode located distal to the substrate and a substrate end located proximal to the substrate.

6. the solid-state battery includes a first main surface facing a substrate and a second main surface facing the first main surface; an end of the end electrode extends to at least one of the first main surface and the second main surface, 5. The packaged solid-state battery of claim 4, wherein the contact portion is located at the end.

7. 5. The packaged solid-state battery according to claim 4, wherein an occupancy rate of the non-contact portion on the outer surface of the end electrode is 50% or more and 100% or less in a cross-sectional view.

8. The packaged solid-state battery according to claim 1 , wherein, in a cross-sectional view, the void portion has an elongated shape extending along a main surface region of the end electrode.

9. The packaged solid-state battery according to claim 1 , wherein a plurality of the voids are formed intermittently along the end electrodes.

10. 2. The packaged solid-state battery according to claim 1, wherein the void portion is continuous over an entire main surface area of ​​the end electrode.

11. The exterior portion includes a coating insulating layer that covers the solid-state battery, The packaged solid-state battery according to claim 1 , wherein the end electrode and the covering insulating layer are spaced apart and face each other via the gap.

12. 2. The packaged solid-state battery of claim 1, wherein a cross-sectional shape of the void corresponds to a cross-sectional shape of an outer surface of the end electrode.

13. the solid-state battery includes a first corner portion located proximal to the substrate; the end surface electrode includes a first corner covering region that covers the first corner, The packaged solid-state battery according to claim 1 , wherein, in a cross-sectional view, a thickness of the first corner covering region is greater than a thickness of other regions other than the first corner covering region.

14. the solid-state battery includes a second corner located distal to the substrate; the end surface electrode includes a second corner covering region that covers the second corner, 14. The packaged solid state battery of claim 13, wherein the other region is the second corner coverage region.

15. 14. The packaged solid state battery of claim 13, wherein the other region is a major surface region of the end electrode.