Encapsulated solid-state battery

Abstract

Provided is a packaged solid-state battery, which is provided with: a substrate; a solid-state battery with an end surface electrode, which is arranged on the substrate; and an exterior portion covering the solid-state battery. The exterior portion contains a resin. A void portion is provided between the end surface electrode and the exterior portion.

Description

Technical Field

[0001] The present disclosure relates to packaged solid batteries. More specifically, the present disclosure relates to solid batteries that are packaged to facilitate substrate mounting. Background Art

[0002] Secondary batteries that can be repeatedly charged and discharged have been used in various applications. For example, secondary batteries are used as power sources for electronic devices such as smartphones and laptop computers.

[0003] In a secondary battery, a liquid electrolyte is generally used as a medium for ion movement that facilitates charging and discharging. In other words, the so-called electrolyte is used in a secondary battery. However, in such a secondary battery, safety is generally required from the perspective of preventing leakage of the electrolyte. In addition, since the organic solvent used in the electrolyte is a flammable substance, safety is also required from this perspective.

[0004] Therefore, solid batteries using solid electrolytes instead of electrolyte solutions are being studied.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application No. 2010-503957 Summary of the invention

[0008] Technical problem to be solved by the invention

[0009] Solid batteries are sometimes mounted on substrates such as printed wiring boards together with other electronic components. The solid battery arranged on the substrate can be covered by a covering member to prevent water vapor from penetrating (Patent Document 1). The covering member is configured to also cover the end face electrodes arranged on the solid battery. In this case, the end face electrode is in physical contact with the solid battery and may deform as the solid battery expands and contracts during charging and discharging. On the other hand, the covering member is arranged on the solid battery with the end face electrode in the area covering the end face electrode. For this reason, the covering member has poor tracking performance to the expansion and contraction of the solid battery compared to the end face electrode, and there is a concern that it may hinder the deformation of the end face electrode. As a result, deformation may occur inside the end face electrode, causing damage to the end face electrode.

[0010] The present invention has been made in view of such technical problems. That is, the main object of the present disclosure is to provide a packaged solid battery in which the risk of damage to the end surface electrodes due to expansion and contraction of the solid battery is reduced.

[0011] Technical solutions for solving technical problems

[0012] In order to achieve the above-mentioned purpose, in one embodiment of the present disclosure, there is provided a packaged solid battery, which comprises: a substrate; a solid battery with end face electrodes, arranged on the substrate; and an outer packaging portion, covering the solid battery, the outer packaging portion containing resin and including a gap portion between the end face electrode and the outer packaging portion.

[0013] Effects of the Invention

[0014] The packaged solid battery according to one embodiment of the present disclosure can reduce the risk of damage to the end surface electrodes due to expansion and contraction of the solid battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a cross-sectional view schematically showing the internal structure of a solid battery.

[0016] Figure 2 It is a cross-sectional view schematically showing the structure of a packaged solid battery according to one embodiment of the present disclosure.

[0017] Figure 3 It is for Figure 2 An enlarged cross-sectional view schematically showing portion A of the encapsulated solid battery is shown.

[0018] Figure 4 1 is an enlarged cross-sectional view schematically showing a portion A of a packaged solid battery according to another embodiment of the present disclosure.

[0019] Figure 5 It is a cross-sectional view schematically showing the structure of a packaged solid battery according to one embodiment of the present disclosure.

[0020] Figure 6 It is for Figure 5 An enlarged cross-sectional view schematically showing portion B of the packaged solid battery is shown.

[0021] Fig. 7A It is a cross-sectional view schematically showing a process of manufacturing a packaged solid battery according to one embodiment of the present disclosure.

[0022] Figure 7B It is a cross-sectional view schematically showing a process of manufacturing a packaged solid battery according to one embodiment of the present disclosure.

[0023] Figure 7C It is a cross-sectional view schematically showing a process of manufacturing a packaged solid battery according to one embodiment of the present disclosure.

[0024] Fig.7D It is a cross-sectional view schematically showing a process of manufacturing a packaged solid battery according to one embodiment of the present disclosure.

[0025] Fig. 7E It is a cross-sectional view schematically showing a process of manufacturing a packaged solid battery according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] The packaged solid battery of the present disclosure is described in detail below. The description will be made with reference to the drawings as needed, but the contents of the drawings are only schematically and exemplarily shown for the purpose of understanding the present disclosure, and the appearance, dimensional ratio, etc. may be different from the actual object.

[0027] The term "encapsulated solid battery" as used herein refers in a broad sense to a solid battery device configured to protect the solid battery from the external environment, and in a narrow sense to a solid battery device having a mountable substrate and protecting the solid battery from the external environment.

[0028] The "cross-sectional observation" mentioned in this specification is based on the shape grasped from the direction roughly perpendicular to the stacking direction in the stacking structure of the solid battery (straightforwardly, it is the shape when cut along a plane parallel to the thickness direction of the layer). In addition, the "top view observation" or "top view observation shape" used in this specification is based on the schematic diagram when the object is observed from the top or bottom along the thickness direction of such a layer (that is, the above-mentioned stacking direction).

[0029] The "up and down direction" and "left and right direction" used directly or indirectly in this specification correspond to the up and down direction and left and right direction in the drawings, respectively. Unless otherwise specified, the same reference numerals or symbols represent the same components / parts or the same meanings. In a suitable scheme, it can be understood that the vertical direction downward (i.e., the direction of gravity) corresponds to the "downward direction" / "bottom side", and the opposite direction corresponds to the "upward direction" / "top side".

[0030] In addition, in this specification, "on" of a component such as a substrate, a solid battery or a layer includes not only the case of contact with the upper surface of the component, but also the case of not contacting the upper surface of the component. That is, "on" of a component such as a substrate, a solid battery or a layer includes the case of forming a new component above the component and / or the case of other components between the new component and the component such as the substrate, solid battery or layer. In addition, "on" does not necessarily refer to the upper side in the vertical direction. "On" is just to indicate the relative positional relationship of multiple components.

[0031] [Basic structure of secondary battery]

[0032] The term "secondary battery" as used herein refers to a battery that can be repeatedly charged and discharged. Therefore, the secondary battery of the present disclosure is not limited to its name, and may include, for example, power storage devices.

[0033] The "solid battery" mentioned in the present disclosure refers to a battery whose constituent elements are composed of solids in a broad sense, and refers to an all-solid battery whose constituent elements (particularly preferably, all constituent elements) are composed of solids in a narrow sense. In a certain appropriate scheme, the solid battery in the present disclosure is a stacked solid battery in which each layer forming a battery constituent unit is stacked on top of each other, and preferably each such layer is composed of a sintered body. "Solid batteries" not only cover so-called "secondary batteries" that can be repeatedly charged and discharged, but also "primary batteries" that can only be discharged. According to a certain appropriate scheme of the present disclosure, a "solid battery" is a secondary battery. "Secondary battery" is not overly restricted to its name, for example, it can also cover storage devices, etc. It should be noted that in the present disclosure, the solid battery included in the package may also be referred to as a "solid battery element."

[0034] The following first describes the basic structure of the solid battery disclosed in the present invention. The structure of the solid battery described here is ultimately just an example for understanding the invention and does not constitute a limitation of the invention.

[0035] [Basic structure of solid-state batteries]

[0036] A solid battery has at least positive and negative electrode layers and a solid electrolyte. Figure 1 As shown, the solid battery 100 includes a solid battery laminate, which includes a battery constituent unit composed of a positive electrode layer 110, a negative electrode layer 120, and at least a solid electrolyte 130 interposed therebetween.

[0037] The solid battery may be formed by firing each layer, or the positive electrode layer, negative electrode layer and solid electrolyte may form a fired layer. Preferably, the positive electrode layer, negative electrode layer and solid electrolyte are fired integrally with each other, so the solid battery stack preferably forms an integrally fired body.

[0038] 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 certain suitable 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 certain suitable embodiment, the negative electrode layer is composed of a sintered body containing at least negative electrode active material particles and solid electrolyte particles.

[0039] The positive electrode active material and the negative electrode active material are substances that participate in the exchange of electrons in the solid battery. Ions move (conduct) between the positive electrode layer and the negative electrode layer via a solid electrolyte to carry out the exchange of electrons, thereby charging and discharging. Each electrode layer in the positive electrode layer and the negative electrode layer is particularly preferably a layer that can embed and deintercalate lithium ions or sodium ions. In other words, the solid battery is preferably a fully solid secondary battery in which lithium ions or sodium ions move between the positive electrode layer and the negative electrode layer via a solid electrolyte to charge and discharge the battery.

[0040] (Positive electrode active material)

[0041] As the positive electrode active material contained in the positive electrode layer, for example, at least one selected from the group consisting of a lithium-containing phosphate compound having a NASICON structure, a lithium-containing phosphate compound having an olivine structure, a lithium-containing layered oxide, and a lithium-containing oxide having a spinel structure can be listed. As an example of a lithium-containing phosphate compound having a NASICON structure, Li3V2(PO4)3 can be listed. As an example of a lithium-containing phosphate compound having an olivine structure, Li3Fe2(PO4)3, LiFePO4 and / or LiMnPO4 can be listed. As an example of a lithium-containing layered oxide, LiCoO2 and / or LiCo can be listed. 1 / 3 Ni 1 / 3 Mn 1 / 3 As an example of a lithium-containing oxide having a spinel structure, LiMn2O4 and / or LiNi 0.5 Mn 1.5 O4, etc. The type of lithium compound is not particularly limited, for example, lithium transition metal composite oxides and lithium transition metal phosphate compounds can be used. Lithium transition metal composite oxides are a general term for oxides containing lithium and one or more transition metal elements as constituent elements, and lithium transition metal phosphate compounds are a general term for phosphate compounds containing lithium and one or more transition metal elements as constituent elements. The type of transition metal element is not particularly limited, for example, cobalt (Co), nickel (Ni), manganese (Mn) and iron (Fe), etc.

[0042] In addition, as a positive electrode active material capable of embedding and de-embedding sodium ions, at least one selected from the group consisting of a sodium-containing phosphate compound having a NASICON structure, a sodium-containing phosphate compound having an olivine structure, a sodium-containing layered oxide, and a sodium-containing oxide having a spinel structure can be listed. For example, in the case of a sodium-containing phosphate compound, at least one selected from the group consisting of Na3V2(PO4)3, NaCoFe2(PO4)3, Na2Ni2Fe(PO4)3, Na3Fe2(PO4)3, Na2FeP2O7, Na4Fe3(PO4)2(P2O7) and NaFeO2 as a sodium-containing layered oxide can be listed.

[0043] In addition, the positive electrode active material may be, for example, an oxide, a disulfide, a chalcogenide, or a conductive polymer. An oxide may be, for example, titanium oxide, vanadium oxide, or manganese dioxide. A disulfide may be, for example, titanium disulfide or molybdenum sulfide. A chalcogenide may be, for example, niobium selenide. A conductive polymer may be, for example, a disulfide, polypyrrole, polyaniline, polythiophene, polyphenylene glycol, polyacetylene, or polyacene.

[0044] (Negative electrode active material)

[0045] As the negative electrode active material contained in the negative electrode layer, for example, at least one selected from the group consisting of oxides, 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 can be listed, wherein the oxide contains 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). As an example of a lithium alloy, Li-Al can be listed. As an example of a lithium-containing phosphate compound having a NASICON structure, Li3V2(PO4)3 and / or LiTi2(PO4)3 can be listed. As an example of a lithium-containing phosphate compound having an olivine structure, Li3Fe2(PO4)3 and / or LiCuPO4 can be listed. As an example of a lithium-containing oxide having a spinel structure, Li4Ti5O 12 wait.

[0046] In addition, the negative electrode active material capable of intercalating and deintercalating sodium ions may 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.

[0047] It should be noted that, in a solid battery, the positive electrode layer and the negative electrode layer may be made of the same material.

[0048] The positive electrode layer and / or the negative electrode layer may also contain a conductive material. The conductive material contained in the positive electrode layer and the negative electrode layer may include at least one of metal materials such as silver, palladium, gold, platinum, aluminum, copper, and nickel, and carbon.

[0049] Furthermore, the positive electrode layer and / or the negative electrode layer may also contain a sintering aid. Examples of the sintering aid include at least one selected from the group consisting of lithium oxide, sodium oxide, potassium oxide, boron oxide, silicon oxide, bismuth oxide, and phosphorus oxide.

[0050] The thickness of the positive electrode layer and the negative electrode layer is not particularly limited, and for example, each may be independently 2 μm to 50 μm, and particularly 5 μm to 30 μm.

[0051] (Positive electrode current collecting layer / Negative electrode current collecting layer)

[0052] Although not an essential element of the electrode layer, the positive electrode layer and the negative electrode layer may also have a positive electrode collector layer and a negative electrode collector layer, respectively. The positive electrode collector layer and the negative electrode collector layer may also have the form of a foil, respectively. However, if more emphasis is placed on improving the electronic conductivity, reducing the manufacturing cost of the solid battery, and / or reducing the internal resistance of the solid battery brought about by integral sintering, the positive electrode collector layer and the negative electrode collector layer may also have the form of a sintered body, respectively. As the positive electrode collector constituting the positive electrode collector layer and the negative electrode collector constituting the negative electrode collector layer, it is preferred to use a material with a high electrical conductivity, for example, silver, palladium, gold, platinum, aluminum, copper and / or nickel, etc. may be used. The positive electrode collector and the negative electrode collector may each have an electrical connection portion for electrical connection to the outside, and may be configured to be electrically connected to the end surface electrode. It should be noted that, in the case where the positive electrode collector layer and the negative electrode collector layer have the form of a sintered body, they may also be composed of a sintered body containing a conductive material and a sintering aid. The conductive material contained in the positive electrode collector layer and the negative electrode collector layer can be selected from the same material as the conductive material that can be contained in the positive electrode layer and the negative electrode layer. The sintering aid contained in the positive electrode collector layer and the negative electrode collector layer can be selected from the same material as the sintering aid that can be contained in the positive electrode layer / negative electrode layer. As described above, in a solid battery, the positive electrode collector layer and the negative electrode collector layer are not necessary, and a solid battery without such a positive electrode collector layer and a negative electrode collector layer can also be considered. That is to say, the solid battery included in the package of the present disclosure can also be a solid battery without a collector layer.

[0053] (Solid Electrolyte)

[0054] The solid electrolyte is a material that can conduct lithium ions or sodium ions. In particular, the solid electrolyte that forms the battery constituent unit in the solid battery can form a layer that can conduct lithium ions between the positive electrode layer 110 and the negative electrode layer 120 (see Figure 1 ). It should be noted that the solid electrolyte only needs to be disposed at least between the positive electrode layer and the negative electrode layer. In other words, the solid electrolyte may also be present around the positive electrode layer and / or the negative electrode layer in a manner extending beyond the positive electrode layer and the negative electrode layer. As a specific solid electrolyte, for example, any one or more of a crystalline solid electrolyte, a glass-based solid electrolyte, and a glass-ceramic solid electrolyte are included.

[0055] Crystalline solid electrolytes include, for example, oxide-based crystalline materials and sulfide-based crystalline materials, etc. Examples of oxide-based crystalline materials include lithium-containing phosphate compounds having a NASICON structure, oxides having a perovskite structure, oxides having a garnet-type or garnet-like structure, and oxide glass-ceramic-based lithium ion conductors.

[0056] Examples of lithium-containing phosphate compounds having a NASICON structure include Li x M y (PO4)3 (1≤x≤2, 1≤y≤2, M is at least one selected from the group consisting of titanium (Ti), germanium (Ge), aluminum (Al), gallium (Ga) and zirconium (Zr). As an example of a lithium-containing phosphate compound having a NASICON structure, for example, Li 1.2 Al 0.2 Ti 1.8 (PO4)3, etc. As an example of an oxide having a perovskite structure, La 0.55 Li 0.35 TiO3, etc. As an example of an oxide having a garnet-type or garnet-like structure, Li7La3Zr2O 12 In addition, sulfide-based crystalline materials include thio-LISICON, such as Li 3.25 Ge 0.25 P 0.75 S4 and Li 10 GeP2S 12 etc. The crystalline solid electrolyte may also include a polymer material (eg, polyethylene oxide (PEO) etc.).

[0057] Glass-based solid electrolytes include, for example, oxide-based glass materials and sulfide-based glass materials. Examples of oxide-based glass materials include 50Li4SiO4·50Li3BO3. In addition, examples of sulfide-based glass materials include 30Li2S·26B2S3·44LiI, 63Li2S·36SiS2·1Li3PO4, 57Li2S·38SiS2·5Li4SiO4, 70Li2S·30P2S5, and 50Li2S·50GeS2.

[0058] Glass ceramic solid electrolytes include oxide glass ceramic materials and sulfide glass ceramic materials. As oxide glass ceramic materials, for example, phosphate compounds containing lithium, aluminum, and titanium (LATP) and phosphate compounds containing lithium, aluminum, and germanium (LAGP) can be used. LATP, for example, is Li 1.07 Al 0.69 Ti 1.46 (PO4)3, etc. In addition, LAGP is, for example, Li 1.5 Al 0.5 Ge 1.5 (PO4), etc. In addition, as sulfide-based glass ceramic materials, there are Li7P3S 11 and Li 3.25 P 0.95 S4 et al.

[0059] In addition, as solid electrolytes capable of conducting sodium ions, for example, sodium-containing phosphate compounds having a NASICON structure, oxides having a perovskite structure, oxides having a garnet-type or garnet-like structure, etc. can be listed. As sodium-containing phosphate compounds having a NASICON structure, Na x M y (PO4)3 (1≤x≤2, 1≤y≤2, M is at least one selected from the group consisting of Ti, Ge, Al, Ga and Zr).

[0060] 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 aid that may be contained in the positive electrode layer / negative electrode layer, for example.

[0061] The thickness of the solid electrolyte is not particularly limited. The thickness of the solid electrolyte layer between the positive electrode layer and the negative electrode layer may be, for example, 1 μm to 15 μm, and particularly 1 μm to 5 μm.

[0062] (End electrode)

[0063] The solid battery 100 is generally provided with an end surface electrode 140. In particular, the end surface electrode 140 is provided on the side surface 100C of the solid battery 100. More specifically, an end surface electrode 140A on the positive electrode side connected to the positive electrode layer 110 and an end surface electrode 140B on the negative electrode side connected to the negative electrode layer 120 are provided (see Figure 1 ). Such an end surface electrode preferably includes a material with high electrical conductivity. There is no particular limitation on the specific material of the end surface electrode, and at least one selected from the group consisting of silver, gold, platinum, aluminum, copper, tin and nickel can be cited.

[0064] [Basic structure of encapsulated solid-state battery]

[0065] The solid battery disclosed in the present invention is a packaged solid battery, that is, a packaged solid battery having a substrate that can be mounted and a structure that protects the solid battery from the external environment.

[0066] Figure 2 1 is a cross-sectional view schematically showing the structure of a packaged solid battery according to an embodiment of the present disclosure. As shown in the figure, a packaged solid battery 1000 according to an embodiment of the present disclosure includes a substrate 200 to support the solid battery 100. Specifically, the packaged solid battery 1000 includes a substrate 200 that can be mounted and a solid battery 100 that is disposed on the substrate 200 and is protected from the external environment.

[0067] like Figure 2 As shown, the substrate 200 has a main surface larger than that of a solid battery, for example. The substrate 200 may be a resin substrate, or may be a ceramic substrate. To put it bluntly, the substrate 200 may also be a substrate falling within the category of a printed wiring substrate, a flexible substrate, an LTCC substrate, or an HTCC substrate. In the case where the substrate 200 is a resin substrate, the substrate 200 may be a substrate configured to include a resin as a base material, for example, a substrate including a resin layer in the laminated structure of the substrate. The resin material of such a resin layer may be any thermoplastic resin and / or any thermosetting resin. In addition, the resin layer may be formed, for example, by impregnating a resin material such as an epoxy resin in a glass fiber cloth.

[0068] The substrate is preferably a component for the external terminal of the packaged solid battery. In other words, the substrate can also be said to be a terminal substrate for the external terminal of the solid battery. Regarding the packaged solid battery having such a substrate, the solid battery can be mounted on other secondary substrates such as a printed wiring board in a form in which the substrate is interposed. For example, the solid battery can be surface-mounted via the substrate by reflow soldering or the like. Therefore, the packaged solid battery disclosed in the present invention is preferably a SMD (SMD: Surface Mount Device) type battery package.

[0069] Such a substrate can be configured to support a solid battery, and can also be understood as a supporting substrate. In addition, since the substrate is a terminal substrate, it is preferred to have wiring or an electrode layer, and it is particularly preferred to have an electrode layer for electrically connecting the upper and lower surfaces or the upper and lower surface layers. The substrate of a suitable scheme has wiring or an electrode layer for electrically connecting the upper and lower surfaces of the substrate, and is a terminal substrate for the external terminals of a packaged solid battery. In such a scheme, since the wiring of the substrate can be used to take out the solid battery from the external terminal, it is not necessary to take out the external terminal of the outer packaging portion while packaging it with the outer packaging portion described below, and the design freedom of the external terminal is improved.

[0070] The substrate 200 according to a preferred embodiment includes electrode layers (upper main surface electrode layer 210 and lower main surface electrode layer 220) for electrically connecting the upper and lower main surfaces of the substrate, and is a component used as an external terminal of the packaged solid battery (see Figure 2 ). In a packaged solid battery having such a substrate, the electrode layer of the substrate and the terminal portion of the solid battery are connected to each other. Preferably, the electrode layer of the substrate and the end surface electrode of the solid battery are electrically connected to each other. For example, the end surface electrode 140A on the positive side of the solid battery is electrically connected to the electrode layer (210A, 220A) on the positive side of the substrate. On the other hand, the end surface electrode 140B on the negative side of the solid battery is electrically connected to the electrode layer (210B, 220B) on the negative side of the substrate. Thus, the electrode layers on the positive and negative sides of the substrate (particularly the electrode layers located on the lower side / bottom side of the package or the pads connected thereto) are provided as the positive and negative terminals of the packaged solid battery, respectively.

[0071] like Figure 2 As shown, in order to achieve electrical connection between the solid battery 100 and the substrate electrode layer 210 of the substrate 200, the end surface electrode 140 of the solid battery 100 can be connected to the substrate electrode layer 210 of the substrate 200 via a bonding component 600. The bonding component 600 is at least responsible for the electrical connection between the end surface electrode 140 of the solid battery 100 and the substrate 200, and can include a conductive adhesive, for example. As an example, the bonding component 600 can be composed of an epoxy-based conductive adhesive containing a metal filler such as Ag.

[0072] Furthermore, in one embodiment of the present disclosure, not only the substrate 200, but also the packaged solid battery 1000 itself can be constructed to prevent water vapor from penetrating as a whole. For example, the solid battery package 1000 involved in one embodiment of the present disclosure can be covered with an outer packaging portion 150 so that the solid battery 100 disposed on the substrate 200 is surrounded as a whole. That is to say, from the perspective that the "outer packaging portion" in this specification refers to the covering component surrounding the solid battery 100 on the substrate 200, the "outer packaging portion" can also be referred to as a "covering portion" or a "packaging portion". Specifically, the main surface 100A and the side surface 100C of the solid battery 100 on the substrate 200 can be packaged to be surrounded by the outer packaging portion 150. According to such a structure, since all the surfaces forming the solid battery 100 will not be exposed to the outside, it is possible to appropriately prevent water vapor from penetrating (i.e., water vapor from entering the solid battery).

[0073] It should be noted that the "water vapor" mentioned in this specification is not particularly limited to water in a gaseous state, but also includes water in a liquid state, etc. That is to say, regardless of the physical state, the term "water vapor" is used to broadly cover water in a gaseous state, water in a liquid state, etc. Therefore, "water vapor" can also be referred to as moisture, etc., and in particular, water in a liquid state can also cover condensed water condensed from water in a gaseous state, etc. Since the entry of water vapor into a solid battery is the main cause of the degradation of battery characteristics, the shape of the solid battery packaged as described above helps to extend the life of the battery characteristics of the solid battery.

[0074] For example, Figure 2 As shown, the outer packaging part 150 can be composed of a coating insulating layer 160 and a coating inorganic layer 170. The solid battery 100 can have a form covered by the coating insulating layer 160 and the coating inorganic layer 170 as the outer packaging part 150. The coating inorganic layer 170 is arranged to cover the coating insulating layer 160. Since the coating inorganic layer 170 is positioned on the coating insulating layer 160, it has a form of the solid battery 100 on the substrate 200 to a large extent as a whole together with the coating insulating layer 160. Furthermore, the coating inorganic layer 170 can adopt a form that also covers the side 250 of the substrate 200. The coating insulating layer 160 is formed to cooperate with the coating inorganic layer 170 to form a suitable water vapor barrier, and the coating inorganic layer 170 is also formed to cooperate with the coating insulating layer 160 to form a suitable water vapor barrier. It should be noted that the coating insulating layer 160 can also reach the side 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 battery may also cover the side surface 250 of the substrate, and the covering inorganic layer 170 may be provided on such covering insulating layer 160 .

[0075] The material of the coating insulating layer can be any type as long as it exhibits insulation. For example, the coating insulating layer can contain a resin, and the resin can be a thermosetting resin or a thermoplastic resin. The coating insulating layer can contain an inorganic filler. The coating insulating layer can be composed of an epoxy resin containing an inorganic filler such as SiC, but this is only an example.

[0076] The material of the coating inorganic layer is not particularly limited, and may be metal, glass, oxide ceramic or a mixture thereof. The coating inorganic layer may be equivalent to an inorganic layer having a thin film form, such as a metal film. For example, the coating inorganic layer may be a plated 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 suitable embodiment, the coating inorganic layer is composed of a Cu-based and / or Ni-based material of 2 μm or more and 50 μm or less formed by plating.

[0077] [Features of the encapsulated solid battery of the present disclosure]

[0078] The inventors of the present application conducted intensive research on a solution for reducing the risk of damage to the end surface electrodes 140 in the above-mentioned packaged solid battery 1000 due to expansion and contraction of the solid battery 100 during charging and discharging, and as a result, came up with the present invention having the following technical concept.

[0079] The present disclosure has the technical concept of "adopting a structure including a gap between the end surface electrode and the outer package". More specifically, the present disclosure has the technical concept of "adopting a structure including a gap between the end surface electrode and the outer package and separating the end surface electrode and the outer package through the gap".

[0080] In order to realize the above technical concept, the present disclosure has the following technical features. Figure 2 As shown, the solid battery 100 disposed on the substrate 200 includes an end surface electrode 140 provided on a side surface 100C of the solid battery 100. The outer packaging unit 150 is provided so as to surround the solid battery 100 on the substrate 200 together with the end surface electrode 140. Figure 3 It is schematically shown Figure 2 FIG. 1 is an enlarged cross-sectional view of a portion A of the packaged solid battery 1000, where portion A is a portion of the boundary region between the end surface electrode 140 and the outer packaging portion 150. Figure 2 and Figure 3As shown, a gap 180 is included between the end surface electrode 140 and the outer packaging part 150. That is, the end surface electrode 140 and the outer packaging part 150 can be opposite to each other with the gap 180 therebetween. In other words, the outer packaging part 150 can be arranged to cover the solid battery 100 in a state where a gap is formed between the outer packaging part 150 and the end surface electrode 140 with the gap 180 therebetween.

[0081] In such a configuration, the end face electrode 140 and the outer packaging portion 150 can be separated from each other via the gap portion 180. That is, the packaged solid battery of the present disclosure includes a portion where the solid battery 100 and the outer packaging portion 150 are separated and opposite to each other and a portion where the solid battery 100 and the outer packaging portion 150 are in contact. In such a configuration, the separated and opposite portions can be located between the end face electrode 140 and the outer packaging portion 150. To put it bluntly, the packaged solid battery of the present disclosure includes a portion where the end face electrode 140 and the outer packaging portion 150 are separated and opposite to each other. This means that the outer packaging portion 150 can be configured to cover the solid battery with the end face electrode in a state where it is at least partially separated from the end face electrode 140.

[0082] The solid battery 100 covered by the outer packaging part 150 has a first main surface 100A opposite to the substrate 200 and a second main surface 100B located opposite to the first main surface 100A. That is, assuming a typical solid battery with two opposite main surfaces, the second main surface 100B located opposite to the substrate 200 is the main surface on the mounting surface side in the SMD type, which can also be called the "bottom surface" or "lower surface". In addition, the second main surface 100B refers to the main surface located on the opposite side of the first main surface 100A, which can also be called the "top surface", "top surface" or "upper surface".

[0083] In addition, the “side surface of the solid battery” refers to the surface connecting the first main surface 100A and the second main surface 100B. In one embodiment of the present disclosure, the end surface electrode 140 may be provided on each of the two side surfaces 100C of the solid battery 100 that are opposite to each other. Specifically, Figure 1 As shown, the positive electrode side end surface electrode 140A connected to the positive electrode layer 110 and the negative electrode side end surface electrode 140B connected to the negative electrode layer 120 can be arranged on two side surfaces 100C opposite to each other. In the present disclosure, the gap portion 180 can be provided in at least one of the positive electrode side end surface electrode 140A and the negative electrode side end surface electrode 140B. That is, the outer packaging portion 150 can cover the solid battery in a state including a portion separated and opposite to at least one of the positive electrode side end surface electrode 140A and the negative electrode side end surface electrode 140B.

[0084] In addition, as described above, the outer packaging part 150 may include a coating insulating layer 160. In a suitable embodiment, the coating insulating layer 160 is provided to cover the solid battery 100, and a coating inorganic layer 170 is provided on the coating insulating layer 160. In such an embodiment, the end surface electrode 140 may include a gap 180 between the end surface electrode 140 and the coating insulating layer 160. In other words, the end surface electrode 140 and the coating insulating layer 160 may be separated and opposed to each other via the gap 180.

[0085] Such a force pulling in the expansion and contraction direction of the solid battery 100 may act on the end surface electrode 140. In the case where the solid battery 100 expands and contracts in the stacking direction of the electrode layers, such an expansion and contraction direction is the same direction as the extension direction of the end surface electrode 140 (refer to Figure 1 ). That is, the expansion and contraction direction can also be understood as the same direction as the extension direction of the side surface 100C of the solid battery. At the side surface 100C of the solid battery, the end surface electrode 140 is joined to the solid battery 100. On the other hand, the outer packaging part 150 is arranged on the solid battery 100 across the end surface electrode 140 in the area covering the end surface electrode 140. Compared with the end surface electrode 140 in physical contact with the solid battery 100, the force acting in the extension direction of the end surface electrode 140 due to the expansion and contraction of the solid battery is difficult to propagate to the outer packaging part 150. For this reason, the outer packaging part 150 may have poor tracking performance for the expansion and contraction of such a solid battery 100.

[0086] In this way, the outer packaging part 150 may have poorer followability to the expansion and contraction of the solid battery 100 than the end surface electrode 140. For this reason, when the end surface electrode 140 and the outer packaging part 150 are joined to each other, the outer packaging part 150 constrains the end surface electrode 140 at the joint surface with the end surface electrode 140 (that is, the outer side surface 145 of the end surface electrode), which may inhibit the deformation of the end surface electrode 140 following the expansion and contraction of the solid battery 100. As a result, when the solid battery 100 expands and contracts, the outer side surface 145 of the end surface electrode 140 is difficult to deform due to the constraint of the outer packaging part 150, while the inner side surface of the end surface electrode 140 physically joined to the solid battery 100 is easy to deform following the expansion and contraction. As a result, since the ease of deformation is different between the inner side surface of the end surface electrode 140 and the outer side surface 145 of the end surface electrode joined to the outer packaging part 150, the inside of the end surface electrode 140 may be deformed, and there is a concern that the end surface electrode 140 is damaged.

[0087] According to the configuration disclosed herein, the outer side surface 145 of the end surface electrode located on the outer packaging part 150 side has a portion separated from the outer packaging part 150 by the gap portion 180, so at such a separated portion, the outer surface of the end surface electrode is not constrained by the outer packaging part 150. That is, by providing the gap portion 180 between the end surface electrode 140 and the outer packaging part 150, the constraint of the outer packaging part 150 on the outer side of the end surface electrode 140 can be relaxed as a whole. For this reason, when the end surface electrode 140 is deformed with the volume change such as the expansion and contraction of the solid battery 100, the influence of the constraint of the outer packaging part 150 can be reduced. As a result, the deformation in the end surface electrode 140 caused by the expansion and contraction of the solid battery 100 is suppressed, and the risk of damage to the end surface electrode 140 can be reduced. Furthermore, by reducing such deformation, the fatigue of the end surface electrode 140 caused by the repeated expansion and contraction of the solid battery 100 can also be reduced. Therefore, degradation, peeling, etc. of the end surface electrode 140 are suppressed, and the long-term reliability of the packaged solid battery can be improved.

[0088] In addition, if Figure 2 As shown, the outer packaging portion 150 is in physical contact with the second main surface 100B of the solid battery. For this reason, when the solid battery 100 expands and contracts in the stacking direction of the electrode layer, the outer packaging portion 150 located on the second main surface 100B of the solid battery can appropriately follow the deformation along the expansion and contraction direction of the solid battery 100. Furthermore, the outer packaging portion 150 is also bonded to the substrate 200 on which the solid battery 100 is configured. Such a bond can help the outer packaging portion 150 to be properly maintained on the solid battery 100. For this reason, even in the scheme in which a gap portion 180 is formed between the end surface electrode 140 and the outer packaging portion 150 as described above, the outer packaging portion 150 can be properly maintained on the solid battery 100 without being easily damaged and / or peeled off due to the deformation caused by the expansion and contraction of the solid battery.

[0089] The end surface electrode 140 and the outer packaging part 150 do not need to be completely separated. In other words, the end surface electrode 140 may partially contact the outer packaging part 150. In one embodiment, the end surface electrode 140 includes a non-contact portion 145A and a contact portion 145B (see Figure 4). According to such a configuration, the contact portion 145B can help support the outer packaging portion 150 on the end surface electrode 140. For example, even when stress is applied near the gap portion 180, the stress is appropriately dispersed to the end surface electrode 140 and / or the outer packaging portion 150 through the contact portion 145B, and the end surface electrode 140 and the outer packaging portion 150 can be prevented from being damaged. Since the outer packaging portion 150 is supported by the contact portion 145B on the end surface electrode 140, the strength of the outer packaging portion 150 can be improved as a whole. Furthermore, at such a contact portion 145B, the end surface electrode 140 can be clamped on the solid battery 100 by the outer packaging portion 150. The contact portion 145B between the end surface electrode 140 and the outer packaging portion 150 can appropriately hold the end surface electrode 140 on the solid battery and help prevent the end surface electrode 140 from being peeled off from the solid battery.

[0090] For example, the contact portion between the end surface electrode 140 and the outer packaging portion 150 may be at least the end portion 141 of the end surface electrode 140. Specifically, the end surface electrode 140 may be in contact with the outer packaging portion 150 at at least one of the substrate side end portion 141a located on the first main surface 100A side of the solid battery and the top surface side end portion 141b located on the second main surface 100B side of the solid battery. The "top surface side end portion" and the "bottom surface side end portion" correspond to the end portion 141 located on the side away from the substrate 200 and the end portion 141 located on the side close to the substrate 200 of the end surface electrode 140, respectively. That is, the contact portion between the end surface electrode 140 and the outer packaging portion 150 may be positioned at the end portion 141 of the end surface electrode located on the second main surface 100B side of the solid battery and / or the substrate 200 side.

[0091] As described above, by providing the outer packaging part 150 with a contact portion with the end 141 of the end surface electrode, the junction between the end 141 of the end surface electrode and the solid battery 100 is covered by the outer packaging part 150. According to such a structure, the end 141 of the end surface electrode can be appropriately clamped to the solid battery by the outer packaging part 150. For this reason, it is possible to appropriately prevent the end surface electrode from being peeled off from the solid battery due to the expansion and contraction of the solid battery 100. Furthermore, since the outer packaging part 150 covers the junction between the end 141 of the end surface electrode and the solid battery 100, it is possible to appropriately inhibit water vapor from entering the solid battery 100 from the connection between the end surface electrode 140 and the solid battery 100. That is, according to the present disclosure, a packaged solid battery that takes into account both reducing the risk of damage to the end surface electrode due to expansion and contraction and preventing water vapor from entering the solid battery can be provided.

[0092] Figure 5Schematically shows a cross-sectional view of a packaged solid battery according to another embodiment. In one embodiment, the end surface electrode 140 can reach at least one of the first main surface 100A and the second main surface 100B of the solid battery. That is, the end 141 of the end surface electrode can extend to at least one of the first main surface 100A and the second main surface 100B of the solid battery. According to such a structure, since the end surface electrode reaches the first main surface 100A, the bonding area between the end surface electrode 140 and the bonding component 600 can be further increased. Therefore, the above structure can be beneficial to improving the connection reliability between the end surface electrode 140 and the bonding component 600.

[0093] The outer packaging part 150 may contact the end surface electrode 140 at the end 141 of the end surface electrode positioned on the first main surface 100A and / or the second main surface 100B. That is, the contact portion of the outer packaging part 150 with the end surface electrode 140 may be positioned at the end 141 of the end surface electrode extending to the first main surface 100A and / or the second main surface 100B.

[0094] According to such a structure, the end face electrode 140 can extend along the side surface 100C of the solid battery and the first main surface 100A and / or the second main surface 100B. That is, since the bonding area between the end face electrode 140 and the solid battery 100 is further increased, it is possible to properly prevent the end face electrode from peeling off due to the volume change of the solid battery. Furthermore, since the outer packaging part 150 and the end face electrode 140 are bonded to each other at the end 141 of the end face electrode extending to the first main surface 100A and / or the second main surface 100B, the end face electrode 140 can be properly clamped on the solid battery 100 by the outer packaging part 150. As a result, it is possible to more properly prevent the end face electrode from peeling off from the solid battery due to the expansion and contraction of the solid battery.

[0095] Figure 4 1 is an enlarged cross-sectional view schematically showing a boundary region between an end surface electrode 140 and an outer packaging portion 150 in another embodiment of the present disclosure. As shown in the figure, the packaged solid battery may include a plurality of gaps 180. The plurality of gaps 180 may be formed intermittently along the end surface electrode 140. That is, the plurality of gaps 180 may be formed intermittently by respectively providing a plurality of contact portions 145B with the outer packaging portion 150 and a plurality of non-contact portions 145A with the outer packaging portion 150 in the end surface electrode 140.

[0096] The "intermittently formed voids" in this specification may not necessarily mean that the plurality of voids 180 are independently formed. For example, when observed in cross section, the plurality of voids 180 may be in a state where adjacent voids 180 are partially connected to each other. This means that the inner side surface 155 of the outer packaging portion opposite to the end surface electrode 140 may be a surface including projections and depressions when observed in cross section. For example, the contact portion 145B and the non-contact portion 145A of the end surface electrode 140 and the outer packaging portion 150 may be alternately and repeatedly arranged. In such a structure, the plurality of voids 180 may be arranged irregularly along the end surface electrode, or may be arranged roughly regularly.

[0097] In this way, when the packaged solid battery intermittently includes a plurality of gaps 180, the non-contact portion 145A of the end face electrode 140 that is not constrained by the outer packaging portion 150 is provided at a plurality of locations of the end face electrode 140, thereby being able to avoid the local existence of the non-constrained portion and the constrained portion of the end face electrode. For this reason, the deformation of the end face electrode caused by the expansion and contraction of the solid battery is more effectively alleviated as a whole, and the risk of damage to the end face electrode can be appropriately reduced. In addition, by ensuring the non-contact portion 145A on one side and providing the contact portion 145B at a plurality of locations on the other side, the deformation of the end face electrode 145 can be suppressed by the non-contact portion 145A, and the end face electrode 145 can be appropriately maintained on the solid battery 100 by the contact portion 145B.

[0098] In a suitable embodiment, when observed in cross section, the void 180 has a strip shape extending along the end surface electrode 140. In other words, the cross-sectional shape of the void 180 may be a strip shape or a flat shape along the extension direction of the end surface electrode 140. In addition, in an embodiment having a plurality of voids 180, the cross-sectional shapes of the voids 180 do not necessarily need to be the same, and may have different cross-sectional shapes. For example, the cross-sectional shapes of the plurality of voids 180 may be strip shapes of different sizes.

[0099] The gap portion 180 having a long strip-shaped cross-sectional observation shape can extend along the main surface area 143 of the end surface electrode. In a certain appropriate scheme, the gap portion 180 has a long strip-shaped cross-sectional shape extending along the outer side surface 145 of the main surface area 143 of the end surface electrode. The "main surface area of ​​the end surface electrode" in this specification means the area of ​​the end surface electrode 140 located on the side 100C of the solid battery. In other words, the gap portion 180 can be located on the end surface electrode 140 located on the side 100C of the solid battery. Through such a structure, the end surface electrode 140 is separated from the outer packaging portion 150 in a wider area, which can more effectively alleviate the constraint of the outer packaging portion 150 on the end surface electrode 140. To this end, the end surface electrode can more appropriately follow the volume change of the solid battery, and the deformation that may occur in the end surface electrode can be suppressed, thereby reducing the risk of damage to the end surface electrode.

[0100] In addition, the cross-sectional shape of the gap 180 may correspond to the cross-sectional shape of the outer side surface 145 of the end surface electrode. Specifically, when viewed in cross section, the gap 180 may have a shape corresponding to the cross-sectional shape of the outer contour forming surface of the end surface electrode 140. For example, Figure 6 As shown, in the case where the outer side surface 145 of the end surface electrode has a curved cross-sectional shape, the gap portion 180 can have a cross-sectional shape of an elongated strip that is curved in a manner along such a curved portion. According to such a structure, when observed in cross-section, the gap portion 180 can extend along the outer side surface 145 of the end surface electrode in a manner having a certain width. In other words, the end surface electrode 140 and the outer packaging portion 150 can include portions that are opposite to each other at a certain interval. As a result, the restraining force of the outer packaging portion 150 on the end surface electrode 140 is more appropriately reduced, so even if deformation occurs in the end surface electrode 140 due to expansion and contraction of the solid battery 100, excessive deformation will not occur inside the end surface electrode 140, and the risk of damage to the end surface electrode 140 can be reduced.

[0101] In one embodiment, the gap 180 may be continuous throughout the entire main surface region 143 of the end surface electrode. In other words, the end surface electrode 140 may be separated from the outer packaging portion 150 and face the entire main surface region 143. In such an embodiment, Figure 2 and Figure 5 As shown, the void portion 180 may have a cross-sectional observation shape that is long and extends throughout the main surface area 143 of the end surface electrode. In addition, although not shown in the figure, such a void portion 180 may be connected not only in the top view direction, but also in the cross-sectional observation direction. That is, the void portion 180 may be two-dimensionally continuous throughout the main surface area 143 of the end surface electrode. Through such a structure, the constraint of the outer packaging portion on the end surface electrode is more effectively alleviated, and the end surface electrode can more appropriately follow the volume change of the solid battery. Therefore, according to the present disclosure, a more appropriately packaged solid battery can be provided in which the deformation that may occur in the end surface electrode is reduced and the risk of damage to the end surface electrode due to the volume change of the solid battery is reduced.

[0102] In cross-sectional view, the width W of the gap 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 Figure 3 Here, the width W of the gap portion can also be understood as the distance between the end surface electrode 140 and the outer packaging portion 150 due to the gap portion 180. In addition, it should be noted that the width W of the gap portion can be appropriately changed according to the size of the solid battery, the thickness of the end surface electrode, and the thickness of the outer packaging portion. For example, Figure 4As shown, the plurality of gaps 180 may have different widths respectively.

[0103] In addition, when viewed in cross section, the non-contact portion 145A between the outer packaging portion 150 and the end surface electrode 140 may be larger than the contact portion 145B (see Figure 4 ). That is to say, the contact ratio between the outer packaging part 150 and the end surface electrode 140 can be less than 50%. In other words, on the outer side surface 145 of the end surface electrode, the non-contact portion 145A can account for more than 50%. For example, when observed in cross section, the proportion of the non-contact portion 145A relative to the length of the outer side surface of the end surface electrode can be more than 50% and less than 100%, more than 60% and less than 99%, or more than 65% and less than 99%, for example, it can be more than 70% and less than 95%. When the non-contact portion 145A that occupies the entire length of the outer side surface 145 of the end surface electrode is within the above range when observed in cross section, the end surface electrode can appropriately follow the expansion and contraction of the solid battery, and the risk of the end surface electrode breaking due to the volume change of the solid battery can be reduced.

[0104] like Figure 5 As shown, the end surface electrode 140 can be arranged to cover the corner of the solid battery. In this specification, the "corner of the solid battery" means the corner between the main surface 100A or 100B and the side 100C of the solid battery, covering the top corner where the main surface 100A or 100B intersects with the two side surfaces 100C and the corner between the main surface 100A or 100B and the side 100C. Specifically, the solid battery 100 has a first corner 102a located on a side close to the substrate 200 and a second corner 102b located on a side away from the substrate 200, and the end surface electrode 140 can be arranged to cover at least one of the first corner 102a and the second corner 102b. In such an embodiment, the end surface electrode 140 covering the first corner 102a can be referred to as the first corner covering area 142a, and the end surface electrode 140 covering the second corner 102b can be referred to as the second corner covering area 142b.

[0105] Figure 6 It is schematically shown Figure 5 The enlarged cross-sectional view of part B in the packaged solid battery 1000 shown is shown, and part B is the connection part between the end face electrode 140 and the joining component. When observed in cross-section, the thickness Ta of the first corner covering area 142a can be greater than the thickness of other areas outside the first corner covering area 142a. Here, the thickness of the corner covering area refers to the thickness of the end face electrode 140 in the extension direction of the main surface of the solid battery. Specifically, it means the distance from the contact point between the corner of the solid battery covered by the corner covering area and the inner side surface of the end face electrode 140 to the intersection of the extension line of the extension direction of the main surface of the solid battery and the outer side surface 145 of the end face electrode. As shown Figure 6As shown, when viewed in cross section, the end surface electrode 140 covering the first corner 102a may have a greater thickness than other regions. In other words, when viewed in cross section, the end surface electrode 140 may be arranged to be relatively thicker in the first corner covering region 142a.

[0106] Among the stresses caused by the expansion and contraction of the solid battery 100, the stress acting from the solid battery 100 side toward the substrate 200 side may increase as it moves from the solid battery 100 to the end face electrode 140 side. That is, among the stresses acting from the solid battery 100 side toward the substrate 200 side, the stress along the end face electrode 140 may be relatively the largest. In particular, a greater stress may act in the first corner covering area 142a covering the first corner 102a located on the substrate 200 side, and therefore there is a possibility of damage due to such stress. In the present disclosure, as described above, an end face electrode having a relatively large thickness at the first corner covering area 142a is provided, thereby being able to provide a packaged solid battery with improved connection reliability of the end face electrode.

[0107] More specifically, when viewed in cross section, the thickness Ta of the first corner covering region 142a of the end surface electrode may be greater than the thickness Tb of the second corner covering region 142b located on the side away from the substrate 200 (see FIG. Figure 5 ). As described above, the stress caused by the expansion and contraction of the solid battery may be greater on the first corner 102a side located on the side close to the connection portion with the substrate 200 than on the second corner 102b located on the second main surface 100B side of the solid battery. For this reason, when observed in cross section, the first corner coating area 142a may have a greater thickness than the second corner coating area 142b. According to such a structure, a packaged solid battery with a reduced risk of damage to the end face electrode at the corner coating area can be provided.

[0108] When observed in cross section, the ratio of the thickness Ta of the first corner covering region 142a of the end surface electrode to the thickness Tb of the second corner covering region 142b can be 101% or more and 500% or less, 200% or more and 400% or less, or 280% or more and 370% or less, for example, 300% or more and 350% or less. When observed in cross section, when the thickness Ta of the first corner covering region 142a of the end surface electrode is within the above range, a packaged solid battery with improved connection reliability of the end surface electrode can be provided.

[0109] Furthermore, when observed in cross section, the thickness Ta of the end surface electrode 140 at the first corner covering region 142a may be greater than the thickness Tc of the end surface electrode 140 at the main surface region 143 located on the side surface 100C of the solid battery. Figure 5 and Figure 6As shown, when viewed in cross section, the thickness of the end surface electrode 140 can gradually increase from the area on the substrate 200 side in the main surface area to the first corner covering area 142a. According to such a structure, a packaged solid battery with reduced risk of end surface electrode damage at the corner covering area can be provided.

[0110] The structure of the packaged solid battery in this specification can be observed from an image obtained by cutting a cross section in the cross-sectional observation direction using an ion milling device (manufactured by Hitachi High-Technologies Corporation, model SU-8040) and using a scanning electron microscope (SEM) (manufactured by Hitachi High-Technologies Corporation, model SU-8040). In addition, the dimensions of the gap and the end surface electrode mentioned in this specification can also refer to values ​​calculated from the dimensions measured from the image obtained by the above method.

[0111] [Method for manufacturing encapsulated solid battery]

[0112] The object of the present disclosure can be obtained by the following process: preparing a solid battery including a battery constituent unit having a positive electrode layer, a negative electrode layer and a solid electrolyte between these electrodes, and then packaging the solid battery (see Figures 7A to 7E ).

[0113] The production of the solid battery of the present disclosure can be roughly divided into the production of the solid battery itself (hereinafter also referred to as “battery before packaging”), which is equivalent to the preparatory stage of packaging, the preparation of the substrate, and packaging.

[0114] 《Method for manufacturing battery before packaging》

[0115] 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 composite method thereof. In other words, the pre-packaged battery itself can be manufactured according to a conventional solid battery manufacturing method (therefore, the raw materials such as the solid electrolyte, organic binder, solvent, any additive, positive electrode active material, negative electrode active material, etc. described below can use materials used in the manufacture of known solid batteries).

[0116] In order to better understand the present disclosure, a certain manufacturing method is exemplified below, but the present disclosure is not limited to this method. In addition, the following matters such as the order of recording over time are ultimately only for the convenience of explanation and are not necessarily limited to this.

[0117] (Formation of laminated blocks)

[0118] A solid electrolyte, an organic binder, a solvent, and any additives are mixed to prepare a slurry. Next, the prepared slurry is fired to form a sheet containing a solid electrolyte.

[0119] 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 any 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 any additives.

[0120] The positive electrode paste is printed on the sheet, and a current collecting layer and / or a negative layer is printed as needed. Similarly, the negative electrode paste is printed on the sheet, and a current collecting layer and / or a negative layer is printed as needed.

[0121] The sheets printed with the positive electrode paste and the sheets printed with the negative electrode paste are alternately stacked to obtain a laminate. It should be noted that the outermost layer (uppermost layer and / or lowermost layer) of the laminate may be an electrolyte layer or an insulating layer, or may be an electrode layer.

[0122] (Formation of battery sintered body)

[0123] After the stack is crimped and integrated, it is cut into a specified size. The obtained cut stack is degreased and fired. Thus, a fired stack is obtained. It should be noted that the stack can also be degreased and fired before cutting, and then cut.

[0124] (Formation of end surface electrodes)

[0125] The end surface electrode 140A on the positive electrode side can be formed by applying a conductive paste to the exposed side of the positive electrode in the fired laminate. Similarly, the end surface electrode 140B on the negative electrode side can be formed by applying a conductive paste to the exposed side of the negative electrode in the fired laminate. Fig. 7A As shown, the end surface electrodes 140 on the positive electrode side and the negative electrode side may be provided to reach the main surface of the fired laminate. The component of the end surface electrodes may be selected from at least one selected from silver, gold, platinum, aluminum, copper, tin, and nickel.

[0126] It should be noted that the end surface electrodes 140 on the positive electrode side and the negative electrode side are not limited to being formed after the stack is fired, but may be formed before firing and fired simultaneously.

[0127] After the above-mentioned steps, the desired pre-packaging battery (equivalent to Fig. 7A The solid state battery 100 shown).

[0128] (Gap Formation Process)

[0129] Next, the outer side surface 145 of the end surface electrode may be subjected to a process for forming a gap between the end surface electrode 140 and the outer packaging portion. The gap between the end surface electrode 140 and the outer packaging portion may be formed by applying a gap forming agent 190 before forming the outer packaging portion (see Figure 7B ). For example, after the end surface electrode 140 is formed, the void forming agent 190 for forming the void portion may be applied to the end surface electrode 140. The void forming agent 190 may be applied only to the portion of the end surface electrode 140 where the void portion is provided. For example, the void forming agent 190 may be applied to the entire end surface electrode 140, or may be applied only to a portion of the end surface electrode, for example, only to the main surface region 143 of the end surface electrode located on the side surface of the solid battery (see Figure 5 ).

[0130] As an example of the gap forming agent used, for example, it can be used to form the cover insulating layer 160 described below (see Figure 7C ) is a well-known material that vaporizes near the heating temperature in the molding process of the coating insulating layer. Such a gap-forming agent can be selected from any material according to the formation conditions of the coating insulating layer (for example, the heating temperature, etc.). Examples of such a gap-forming agent include wax-based materials such as paraffin wax and microcrystalline wax, but they are only examples. When such a gap-forming agent is used, when heating is performed during the molding process for forming the coating insulating layer, the gap-forming agent vaporizes, penetrates into the coating insulating layer and disappears, and as a result, a gap portion is formed between the end surface electrode 140 and the coating insulating layer.

[0131] In addition, the void former may be a material that reduces the adhesion between the end face electrode 140 and the outer packaging portion. For example, the void former may be a known material that improves the releasability of the outer packaging portion provided on the end face electrode 140 from the end face electrode. Examples of such void formers include fluorine-based materials, silicone-based materials, and wax-based materials, but these are merely examples. When such a void former is used, the outer packaging portion is separated from the end face electrode 140 at the portion where the void former is applied, and a void portion is formed between the end face electrode 140 and the outer packaging portion.

[0132] Alternatively, the void former may be a foaming material such as a foaming resin. The foaming resin may be a resin that foams to form a foamed body during the molding of the outer packaging portion. The foaming resin is not particularly limited, and a known foaming resin used in the foaming molding of the resin may be used. For example, the foaming material may be a material obtained by mixing at least one of a chemical foaming agent and foaming beads into a thermoplastic resin. It should be noted that in the final packaged solid battery, it is preferred that no void former as described above remains, but the packaged solid battery may also contain a void former.

[0133] 《Substrate Preparation》

[0134] In this step, a substrate is prepared.

[0135] Although not particularly limited, in the case of using a resin substrate as a substrate, its preparation can be carried out by stacking multiple layers and heating and pressurizing. For example, a resin sheet formed by impregnating a resin raw material into a fiber cloth that becomes a substrate is used to form a substrate precursor. After forming the substrate precursor, the substrate precursor is heated and pressurized with a press. On the other hand, in the case of using a ceramic substrate as a substrate, its preparation can be, for example, by hot pressing a plurality of raw sheets to form a raw sheet laminate, and the raw sheet laminate is fired to obtain a ceramic substrate. The preparation of the ceramic substrate can be carried out, for example, according to the production of an LTCC substrate. The ceramic substrate can have vias and / or pads. In such a case, for example, a punch press or a carbon dioxide laser can be used to form a hole on the raw sheet, and a conductive paste material can be filled in the hole, or a printing method can be implemented to form a precursor of conductive parts such as vias and pads. It should be noted that pads, etc. can also be formed after the firing of the raw sheet laminate.

[0136] Through the above steps, the desired substrate 200 can be finally obtained.

[0137] Encapsulation

[0138] Next, the battery and substrate obtained above were packaged (see Figure 7C to Figure 7E ).

[0139] First, the pre-packaged battery 100 is placed on the substrate 200. That is, an "unpackaged solid battery" (hereinafter, the battery to be packaged is also referred to as a "solid battery") is placed on the substrate.

[0140] Preferably, the solid battery 100 is arranged on the substrate in such a manner that the conductive portion of the substrate and the end surface electrode 140 of the solid battery 100 are electrically connected to each other. For example, a conductive paste can be provided on the substrate, thereby electrically connecting the conductive portion of the substrate and the end surface electrode 140 of the solid battery 100 to each other. More specifically, the conductive portions (especially the lower pad / bottom pad) on the positive and negative sides of the main surface of the substrate are aligned with the end surface electrodes 140 of the positive and negative electrodes of the solid battery 100, respectively, and the wiring is connected using a conductive paste (for example, Ag conductive paste). That is, the precursor of the joining component responsible for the electrical connection between the solid battery 100 and the substrate can be pre-set on the substrate.

[0141] The precursor of such a bonding component can be provided by printing a conductive paste such as a nano paste, an alloy paste, a solder material, etc., which does not require cleaning of a flux, etc. after formation, in addition to an Ag conductive paste. Next, the solid battery 100 is arranged on the substrate so that the end surface electrode 140 and the precursor of the bonding component are in contact with each other, and a heat treatment is performed, so that a bonding component that facilitates electrical connection between the solid battery 100 and the substrate is formed from the precursor.

[0142] Next, the outer packaging part 150 is formed. As the outer packaging part 150, a coating insulating layer 160 and a coating inorganic layer 170 may be provided.

[0143] First, the covering insulating layer 160 is formed so as to cover the solid battery 100 on the substrate 200 (see Figure 7C ). Therefore, the raw material of the coating insulating layer is provided in a manner that covers the solid battery 100 on the substrate as a whole. In the case where the coating insulating layer is composed of a resin material, a resin precursor is arranged on the substrate and cured to form the coating insulating layer. In a suitable embodiment, the molding of the coating insulating layer can also be performed by pressurizing with a mold. The coating insulating layer that seals the solid battery 100 on the substrate can be molded by compression molding, but this is just an example. As long as it is a resin material generally used in molding, the raw material of the coating insulating layer can also be in the form of particles, and its type can also be thermoplastic. It should be noted that such molding is not limited to mold molding, and can also be performed by grinding, laser processing and / or chemical treatment.

[0144] During the step of forming the covering insulating layer 160, the gap forming agent 190 coated on the end surface electrode 140 is used to form a gap portion 180 between the end surface electrode 140 and the covering insulating layer 160 (see Fig.7D ). For example, the gap forming agent may be vaporized and disappear due to heating in the molding process of the covering insulating layer 160, thereby forming the gap portion 180.

[0145] After forming the covering insulating layer 160, the covering inorganic layer 170 is formed (see Fig. 7E The coating inorganic layer 170 may be formed by plating the coating precursor. In one embodiment, the coating inorganic layer is formed on the coating precursor by forming a plating film on the exposed surface other than the bottom surface of the coating precursor (ie, other than the bottom surface of the support substrate).

[0146] Through the above-mentioned steps, a package having a gap between the end surface electrode and the outer packaging part can be obtained. In other words, the "packaged solid battery" involved in the present disclosure can be finally obtained.

[0147] It should be noted that, although not shown, the inorganic coating layer can reach the main surface of the substrate located on the bottom side opposite to the main surface of the substrate opposite to the solid battery. That is, as an outer packaging portion, the insulating coating layer and / or the inorganic coating layer can extend to the side of the substrate, and extend beyond the side to the bottom main surface of the substrate (particularly its peripheral portion). In the case of such a form, a packaged solid battery that is more appropriately prevented from infiltrating moisture such as water from the outside reaching the solid battery can be realized.

[0148] In addition, the coated inorganic layer can also be set as a multilayer structure consisting of at least two layers. Such a multilayer structure is not particularly limited to materials of different types, but can also be materials of the same type. For example, the coated inorganic layer can be a multilayer structure obtained by stacking two or more layers of a dry coating formed by dry plating and a wet coating formed by wet plating in any order. When such a multilayer structure of the coated inorganic layer is provided, it is easy to more appropriately constitute a water vapor barrier for a solid battery.

[0149] It should be noted that a water vapor barrier layer may be formed on the substrate in advance. In other words, a water vapor barrier may be formed on the substrate in advance before combining the substrate and the solid battery package.

[0150] There are no particular restrictions on the water vapor barrier layer as long as it can form a desired barrier layer. For example, in the case of a "water vapor barrier layer having Si-O bonds and Si-N bonds", it is preferably formed by applying a liquid raw material and irradiating ultraviolet rays. In other words, the water vapor barrier layer is formed under relatively low temperature conditions (e.g., temperature conditions of about 100°C) without using a vapor deposition method such as CVD or PVD.

[0151] Specifically, for example, a raw material containing silazane is prepared as a liquid raw material, the liquid raw material is applied to a substrate by spin coating or spray coating, and dried to form a barrier precursor. Then, the barrier precursor is irradiated with UV in a nitrogen-containing atmosphere, thereby obtaining a "water vapor barrier layer having Si-O bonds and Si-N bonds".

[0152] It should be noted that it is preferred to partially remove the barrier layer at the junction between the conductive portion of the substrate and the end surface electrode of the solid battery so that there is no water vapor barrier layer at this location. Alternatively, a mask may be used to prevent the formation of a water vapor barrier layer at the junction. In other words, a mask may be applied to the region that becomes the junction to form a water vapor barrier layer as a whole, and then the mask may be removed.

[0153] Although the embodiments of the present disclosure have been described above, these are merely typical examples. It is easy for a person skilled in the art to understand that the present disclosure is not limited thereto, and various schemes are conceivable within the scope of the gist of the present disclosure.

[0154] It should be noted that the above-described one embodiment of the present disclosure includes the following appropriate aspects.

[0155] Option 1:

[0156] A packaged solid battery, comprising:

[0157] substrate;

[0158] A solid battery with end electrodes, disposed on the substrate; and

[0159] an outer packaging portion, covering the solid battery,

[0160] The outer packaging portion includes a resin,

[0161] A gap portion is included between the end surface electrode and the outer package portion.

[0162] Option 2:

[0163] According to the packaged solid battery described in the first embodiment, the packaged solid battery includes a portion where the solid battery is separated from and opposed to the outer packaging portion and a portion where the solid battery is in contact with the outer packaging portion.

[0164] The separated and opposed portions are located between the end surface electrodes and the outer packaging portion.

[0165] Option 3:

[0166] According to the packaged solid battery of the first or second aspect, the gap is located between the outer packaging portion and at least one of the end surface electrode on the positive electrode side and the end surface electrode on the negative electrode side.

[0167] Option 4:

[0168] According to the packaged solid battery described in any one of the first to third aspects, the plurality of gaps are formed intermittently along the end surface electrodes.

[0169] Option 5:

[0170] According to the packaged solid battery described in any one of the first to fourth aspects, the end surface electrode includes a contact portion and a non-contact portion with the outer packaging portion.

[0171] Plan 6:

[0172] According to the packaged solid battery described in the fifth aspect, the contact portion is positioned at least one of the top surface side end portion of the end surface electrode located away from the substrate and the substrate side end portion located close to the substrate.

[0173] Option 7:

[0174] According to the packaged solid battery of the fifth or sixth aspect, the solid battery comprises a first main surface facing the substrate and a second main surface located at a position facing the first main surface.

[0175] The end of the end surface electrode reaches at least one of the first main surface and the second main surface.

[0176] The contact portion is located at the end portion.

[0177] Plan 8:

[0178] According to the packaged solid battery described in any one of the first to seventh aspects, the void portion has a strip shape extending along the main surface region of the end surface electrode when viewed in cross section.

[0179] Plan 9:

[0180] According to the packaged solid battery as described in any one of the first to eighth aspects, the void portion is continuous over the entire main surface region of the end surface electrode.

[0181] Plan 10:

[0182] According to the packaged solid battery described in any one of the first to ninth embodiments, the outer packaging portion includes a coating insulating layer covering the solid battery,

[0183] The end surface electrode is spaced apart from and opposed to the insulating cover layer via the gap.

[0184] Plan 11:

[0185] According to the packaged solid battery described in any one of the first to tenth aspects, the cross-sectional shape of the gap portion corresponds to the cross-sectional shape of the outer side surface of the end surface electrode.

[0186] Plan 12:

[0187] According to the packaged solid battery described in any one of the first to eleventh aspects, in cross-sectional view, the non-contact portion occupies a ratio of 50% to 100% of the outer side surface of the end surface electrode.

[0188] Plan 13:

[0189] According to the packaged solid battery described in any one of the first to twelfth aspects, the solid battery includes a first corner portion located on a side close to the substrate,

[0190] The end surface electrode includes a first corner covering region covering the first corner,

[0191] When viewed in cross section, the thickness of the first corner covering area is greater than the thickness of other areas outside the first corner covering area.

[0192] Plan 14:

[0193] According to the packaged solid battery of the thirteenth aspect, the solid battery has a second corner located on a side away from the substrate,

[0194] The end surface electrode includes a second corner covering region covering the second corner,

[0195] The other area is the second corner covering area.

[0196] Plan 15:

[0197] According to the packaged solid battery of the twelfth or thirteenth aspect, the other region is a main surface region of the end surface electrode.

[0198] Industrial Applicability

[0199] The packaged solid battery disclosed in the present invention can be used in various fields where battery use or power storage is envisioned. The packaged solid battery disclosed in the present invention can be used in the electrical / information / communication field using mobile devices, etc. (for example, including mobile phones, smart phones, laptops and digital cameras, activity meters, wristband computers, electronic paper, etc., RFID tags, card-type electronic money, smart watches and other small electronic machines, etc., or mobile device fields); home / small industrial uses (for example, power tools, golf carts, home / care / industrial robots); large industrial uses (for example, forklifts, elevators, port cranes); transportation system fields (for example, hybrid vehicles, electric vehicles, buses, trams, electric power-assisted bicycles, electric two-wheeled vehicles and other fields); power system uses (for example, various power generation, load regulators, smart grids, home fixed power storage systems and other fields); medical uses (medical equipment fields such as earphones and hearing aids); medical uses (medical management systems and other fields); IoT fields; and space / deep sea uses (for example, space probes, submersible survey ships and other fields), etc., but they are ultimately just examples.

[0200] Description of Reference Numerals

[0201] 100: solid battery; 100A: first main surface of solid battery; 100B: second main surface of solid battery; 100C: side surface of solid battery; 102a: first corner of solid battery; 102b: second corner of solid battery; 110: positive electrode layer; 120: negative electrode layer; 130: solid electrolyte or solid electrolyte layer; 140: end surface electrode; 140A: positive electrode end surface electrode; 140B: negative electrode end surface electrode; 141a: top surface side end; 141b: bottom surface side corner; 142a: first corner covering area; 142b: second corner covering area; 143: main surface area of ​​end surface electrode; 145: outer surface of end surface electrode Side surface; 145A: non-contact portion; 145B: contact portion; 150: outer packaging portion; 155: inner side surface of the outer packaging portion; 160: coated insulating layer; 170: coated inorganic layer; 180: void portion; 190: void former; 200: substrate; 210: substrate electrode layer (upper side of substrate); 210A: substrate electrode layer on the positive side; 210B: substrate electrode layer on the negative side; 220: mounting side substrate electrode layer (lower side of substrate); 220A: mounting side substrate electrode layer on the positive side; 220B: mounting side substrate electrode layer on the negative side; 250: side surface of substrate; 600: bonding component; 1000: encapsulated solid battery.

Claims

1. A packaged solid battery, comprising: substrate; A solid battery with end electrodes, disposed on the substrate; and an outer packaging portion, covering the solid battery, The outer packaging portion includes a resin, The packaged solid battery includes a gap portion between the end surface electrode and the outer packaging portion.

2. The packaged solid battery according to claim 1, wherein The packaged solid battery includes a portion where the solid battery is separated from and opposite to the outer packaging portion and a portion where the solid battery is in contact with the outer packaging portion. The separated and opposed portions are located between the end surface electrodes and the outer packaging portion.

3. The packaged solid battery according to claim 1 or 2, wherein: The gap portion is located between the outer casing and at least one of the end surface electrode on the positive electrode side and the end surface electrode on the negative electrode side.

4. The packaged solid battery according to any one of claims 1 to 3, wherein The end surface electrode includes a contact portion and a non-contact portion with the outer package.

5. The packaged solid battery according to claim 4, wherein: The contact portion is positioned at at least one of an end portion on a top surface side of the end surface electrode located at a position away from the substrate and an end portion on a substrate side located at a position close to the substrate.

6. The packaged solid battery according to claim 4, wherein: The solid battery includes a first main surface facing the substrate and a second main surface located at a position facing the first main surface. The end of the end surface electrode reaches at least one of the first main surface and the second main surface. The contact portion is located at the end portion.

7. The packaged solid battery according to any one of claims 4 to 6, wherein: When observed in cross section, the non-contact portion occupies a ratio of 50% to 100% of the outer side surface of the end surface electrode.

8. The packaged solid battery according to any one of claims 1 to 7, wherein The cavity has a strip shape extending along a main surface region of the end surface electrode when viewed in cross section.

9. The packaged solid battery according to any one of claims 1 to 8, wherein The plurality of gaps are intermittently formed along the end surface electrode.

10. The packaged solid battery according to any one of claims 1 to 8, wherein The cavity portion is continuous over the entire main surface region of the end surface electrode.

11. The packaged solid battery according to any one of claims 1 to 10, wherein: The outer packaging portion includes a coating insulating layer covering the solid battery, The end surface electrode is spaced apart from and opposed to the insulating cover layer via the gap.

12. The packaged solid battery according to any one of claims 1 to 11, wherein The cross-sectional shape of the cavity portion corresponds to the cross-sectional shape of the outer side surface of the end surface electrode.

13. The packaged solid battery according to any one of claims 1 to 12, wherein: The solid battery comprises a first corner portion located on a side close to the substrate, The end surface electrode includes a first corner covering region covering the first corner, When viewed in cross section, the thickness of the first corner covering area is greater than the thickness of other areas outside the first corner covering area.

14. The packaged solid battery according to claim 13, wherein: The solid battery has a second corner located on a side away from the substrate, The end surface electrode includes a second corner covering region covering the second corner, The other area is the second corner covering area.

15. The packaged solid battery according to claim 13, wherein: The other region is a main surface region of the end surface electrode.

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