Solid-state battery, solid-state battery package provided with solid-state battery, and method for manufacturing solid-state battery

Abstract

A solid-state battery according to the present invention is provided with: a battery element in which a positive electrode layer and a negative electrode layer are alternately laminated with a solid electrolyte layer therebetween, in which the positive electrode layer and the negative electrode layer are exposed, and which has at least one side surface parallel to the lamination direction; an insulating layer disposed so as to cover at least a portion of a first end surface of the first electrode layer of one of the electrode layers from among the positive electrode layer and the negative electrode layer exposed at the side surface; and an external electrode disposed on a portion of the side surface so as to cover the insulating layer and a second end surface of the second electrode layer of the other electrode layer from among the positive electrode layer and the negative electrode layer exposed at the side surface, wherein mathematical expression (1), (1): W ≥ W1 > W2, is satisfied [in mathematical expression (1), W represents the width, in the extension direction, of the first end surface, W1 represents the width, in the extension direction, of the insulating layer disposed on the first end surface, and W2 represents the width, in the extension direction, of the external electrode disposed on the insulating layer].

Description

Solid-state battery, solid-state battery package including solid-state battery, and method for manufacturing solid-state battery

[0001] The present disclosure relates to solid-state batteries, solid-state battery packages including solid-state batteries, and methods for manufacturing solid-state batteries.

[0002] In a conventional solid-state battery including a battery element in which multiple electrode layers (positive electrode layers and negative electrode layers) are stacked with a solid electrolyte layer interposed therebetween and a pair of external electrodes on the side surfaces of the battery element along the stacking direction, an insulating layer is disposed between the electrode layers and the external electrodes to prevent short circuits between the electrode layers and the external electrodes. For example, in the solid-state battery of Patent Document 1, the battery element is formed by stacking layers in which such insulating layers are disposed on the same plane as the extending electrode layers. In addition, in the solid-state battery of Patent Document 2, an insulating layer is provided on part of the side surfaces of the battery element (end surfaces of the electrode layers, counter electrode layers, and solid electrolyte layers).

[0003] International Publication No. 2019 / 176940 International Publication No. 2023 / 203795

[0004] However, as a result of intensive research, the present inventors have found that the solid state batteries described in Patent Documents 1 and 2 still have room for improvement in terms of increasing the capacity of the solid state battery and the insulation properties of the insulating layer between the electrode layer and the external electrode.

[0005] The present disclosure has been made in view of the above-mentioned problems. That is, a primary object of the present disclosure is to provide a solid-state battery having a higher capacity and suppressing undesired short circuits between an electrode layer and an external electrode. Another object of the present disclosure is to provide a solid-state battery package including such a solid-state battery. Another object of the present disclosure is to provide a method for manufacturing such a solid-state battery.

[0006] In order to solve the above problems, a solid-state battery according to an embodiment of the present disclosure includes: a battery element in which positive electrode layers and negative electrode layers are alternately stacked with solid electrolyte layers interposed therebetween, the positive electrode layers and the negative electrode layers are exposed, and the battery element has at least one side surface parallel to the stacking direction; an insulating layer arranged to cover at least a portion of a first end surface of a first electrode layer of one of the positive electrode layers and the negative electrode layers exposed at the side surface; and an external electrode arranged on a portion of the side surface to cover a second end surface of a second electrode layer of the other of the positive electrode layers and the negative electrode layers exposed at the side surface and the insulating layer, and satisfies the following mathematical expression (1): [Mathematical Expression 1] W≧W1>W2 (1) [In the mathematical expression (1), W represents the width in the extension direction of the first end surface, W1 represents the width in the extension direction of the insulating layer arranged on the first end surface, and W2 represents the width in the extension direction of the external terminal arranged on the insulating layer].

[0007] A solid-state battery package according to another embodiment of the present disclosure includes: the above-described solid-state battery; a circuit board on which the solid-state battery is mounted and which has a circuit electrically connected to the external electrodes; and an exterior body that covers and seals the solid-state battery via a sealing layer.

[0008] A method for manufacturing a solid-state battery according to another embodiment of the present disclosure is a method for manufacturing the above-described solid-state battery, comprising: arranging an insulating layer on at least a part of a first end surface of a first electrode layer of either the positive electrode layer or the negative electrode layer, the first end surface being exposed on a side surface of a battery element; and arranging an external electrode on at least a part of a second end surface of a second electrode layer of the other of the positive electrode layer and the negative electrode layer, the second end surface being exposed on the side surface of the battery element.

[0009] The present disclosure can provide a solid-state battery having higher capacity and suppressing undesired short circuits between the electrode layer and the external electrode.

[0010] FIG. 1A is a perspective view schematically illustrating the configuration of a solid-state battery according to a first embodiment of the present disclosure. FIG. 1B is a cross-sectional view (cross-sectional view A-A in FIG. 1A ) schematically illustrating the configuration of a solid-state battery according to a first embodiment of the present disclosure. FIG. 1C is a cross-sectional view (cross-sectional view B-B in FIG. 1A ) schematically illustrating the configuration of a solid-state battery according to a first embodiment of the present disclosure. FIG. 2A is a side view (side view when viewed from the side from C1 in FIG. 1A ) schematically illustrating the configuration of a solid-state battery according to a first embodiment of the present disclosure. FIG. 2B is a side view (side view when viewed from the side from C2 in FIG. 1A ) schematically illustrating the configuration of a solid-state battery according to a first embodiment of the present disclosure. FIG. 3 is a side view schematically illustrating the configuration of a solid-state battery according to a second embodiment of the present disclosure. FIG. 4 is a side view schematically illustrating the configuration of a solid-state battery according to a third embodiment of the present disclosure. FIG. 5 is a side view schematically illustrating the configuration of a solid-state battery according to a fourth embodiment of the present disclosure. FIG. 6 is a cross-sectional view schematically illustrating the configuration of a solid-state battery according to a fifth embodiment of the present disclosure. Fig. 7 is a cross-sectional view schematically showing the configuration of a solid-state battery package according to a seventh embodiment of the present disclosure. Fig. 8 is a perspective view schematically showing steps in a manufacturing process for the solid-state battery according to the first embodiment of the present disclosure. Fig. 9 is a perspective view schematically showing steps in a manufacturing process for the solid-state battery according to the first embodiment of the present disclosure. Fig. 10 is a perspective view schematically showing steps in a manufacturing process for the solid-state battery according to the first embodiment of the present disclosure. Fig. 11 is a perspective view schematically showing steps in a manufacturing process for the solid-state battery according to a third embodiment of the present disclosure.

[0011] Hereinafter, a solid-state battery and a manufacturing method thereof according to one aspect of the present disclosure will be described in detail with reference to the drawings as necessary. The drawings include schematic illustrations in part to facilitate understanding of the present disclosure, and may not reflect actual dimensions or proportions.

[0012] The terms "plan view" and "plan view shape" used herein are based on a sketch of the object in a direction parallel to the main surfaces of the electrode layer and the solid electrolyte layer when viewed from above (top side) or below (bottom side), or in a direction parallel to the side surface of the battery element when viewed from the side. Furthermore, the term "cross-sectional view" used herein is based on the shape of the cross section formed when the solid-state battery is cut along a plane perpendicular to a pair of opposing side surfaces of the battery element of the solid-state battery and parallel to the Z direction (the definition of the direction will be described later).

[0013] The "upper and lower directions" and "lower and upper directions" used directly or indirectly in this specification correspond to the upper and lower directions and the left and right directions in the drawings, respectively. Unless otherwise specified, the same symbols or signs indicate the same members, parts, or the same meanings. In a preferred embodiment, the vertically downward direction (i.e., the direction in which gravity acts) can be considered to correspond to the "lower direction" / "bottom side (lower surface side)," and the opposite direction can be considered to correspond to the "upper direction" / "top side (upper surface side, top surface side)."

[0014] Furthermore, in this specification, "on" a substrate, layer, etc., includes not only the case of being in contact with the upper surface of the substrate, layer, etc. (for example, being directly disposed in contact with the upper surface of the substrate, layer, etc.), but also the case of not being in contact with the upper surface of the substrate, layer, etc. (for example, being indirectly disposed via a new film or layer without being in contact with the upper surface of the substrate, layer, etc.). In other words, "on" a substrate, layer, etc. includes the case of a new film or layer being formed above the substrate or layer, and / or the case of another film or layer being interposed between the substrate or layer and the new film or layer. Furthermore, "on" does not necessarily mean the upper side in the vertical direction. "On" merely indicates the relative positional relationship of the substrate, layer, etc.

[0015] When multiple numerical ranges including only one critical value (numerical ranges including only the lower limit or the upper limit) are listed, these numerical ranges can be arbitrarily combined to form a numerical range including both the upper and lower limits. For example, from numerical ranges including only the lower limit such as 1 or more, 3 or more, and 5 or more, and numerical ranges including only the upper limit such as 10 or less, 8 or less, and 6 or less, a numerical range including both the lower and upper limits can be formed as 1 or more and 10 or less.

[0016] In the following embodiments, the positive electrode side will be described as a representative example, and the contents of this description may be applied mutatis mutandis to the negative electrode side.

[0017] First Embodiment: Solid-State Battery The first embodiment relates to a solid-state battery. The solid-state battery according to the first embodiment includes a battery element in which positive and negative electrode layers are alternately stacked with solid electrolyte layers interposed therebetween, the positive and negative electrode layers are exposed, and the battery element has at least one side surface parallel to the stacking direction; an insulating layer arranged to cover at least a portion of a first end surface of a first electrode layer of one of the positive and negative electrode layers exposed at the side surface; and an external electrode arranged on a portion of the side surface to cover a second end surface of a second electrode layer of the other of the positive and negative electrode layers exposed at the side surface and the insulating layer, and satisfies the following formula (1): W≧W1>W2 (1) (In formula (1), W represents the width in the extension direction of the first end surface, W1 represents the width in the extension direction (of the first end surface) of the insulating layer arranged on the first end surface, and W2 represents the width in the extension direction (of the first end surface) of the external terminal arranged on the insulating layer).

[0018] [Mechanism of Action] The solid-state battery according to the first embodiment has a higher capacity and suppresses undesired short circuits between the electrode layer and the external electrode. The reason for this is presumed to be as follows, without being bound by any particular theory. The solid-state battery according to the first embodiment satisfies the following formula (1): W≧W1>W2 (W represents the width in the extension direction of the first end face, W1 represents the width in the extension direction (of the first end face) of the insulating layer disposed on the first end face, and W2 represents the width in the extension direction (of the first end face) of the external terminal disposed on the insulating layer). Because W1>W2, at least a portion of the first end faces of the first electrode layers of the positive and negative electrodes are covered by the insulating layer on the side faces where the external electrodes of the solid-state battery are disposed. Even when the first end faces are exposed on the side faces, the exposed surfaces of the first end faces are significantly separated from the external electrodes, thereby suppressing undesired conduction (short circuits) between the external electrodes and the first end faces. A method for determining whether formula (1) is satisfied will be described later.

[0019] Furthermore, the insulating layer is disposed so as to cover the side surface of the battery element. The insulating layer is not disposed so as to be aligned in the extension direction of the electrode layer as in Patent Document 1. Therefore, compared to Patent Document 1, the insulating layer can reduce the dead space in the extension direction of the electrode layer, and this space can be used for the electrode layer. This makes it possible to achieve a high capacity of the solid-state battery. From the above, it is considered that the solid-state battery according to the first embodiment has a higher capacity and suppresses undesired short circuits between the electrode layer and the external electrode.

[0020] <Configuration of Solid-State Battery> A solid-state battery according to the first embodiment and the components constituting the solid-state battery will be described with reference mainly to FIGS. 1A , 1B , 1C , 2A , and 2B . FIG. 1A is a perspective view schematically illustrating the configuration of the solid-state battery according to the first embodiment. FIG. 1B is a cross-sectional view (cross-sectional view A-A in FIG. 1 ) schematically illustrating the configuration of the solid-state battery according to the first embodiment. FIG. 1C is a cross-sectional view (cross-sectional view B-B in FIG. 1 ) schematically illustrating the configuration of the solid-state battery according to the first embodiment. FIG. 2A is a side view (side view when viewed from the side from C1 in FIG. 1A ) schematically illustrating the configuration of the solid-state battery according to the first embodiment of the present disclosure. FIG. 2B is a side view (side view when viewed from the side from C2 in FIG. 1A ) schematically illustrating the configuration of the solid-state battery according to the first embodiment of the present disclosure.

[0021] 1A to 1C, the Z direction is the direction (stacking direction) in which the electrode layers 111 (positive electrode layer 111a and negative electrode layer 111b) and the solid electrolyte layer 112 in the solid-state battery 100 are stacked. The X direction is perpendicular to the Z direction and is the direction in which a pair of opposing side surfaces (first side surface 113a and second side surface 113b) in the stack (battery element 110) of the solid-state battery 100 face each other (the long axis direction of the solid-state battery). The Y direction is perpendicular to the Z direction and the X direction (the short axis direction of the solid-state battery). The reverse Z direction is the vertically downward direction, and the forward Z direction is the vertically upward direction. This also applies to the other figures below. In addition, the letter a in the reference numerals in the figures is generally attached to the positive electrode layer itself and components related to the positive electrode layer, which are mainly arranged on the left side (relatively on the reverse X direction side) in FIG. 1B. The letter "b" attached to the reference numerals in the drawings is generally attached to the negative electrode layer itself and members related to the negative electrode layer, which are mainly arranged on the right side (relatively the side in the forward X direction) in FIG. 1B.

[0022] 1A to 1C, the solid-state battery 100 according to the first embodiment includes a battery element 110 having a pair of side surfaces 113a, 113b that are parallel to the stacking direction and face each other, insulating layers (a first insulating layer 120a and a second insulating layer 120b) that are disposed on the side surfaces 113a, 113b of the battery element 110, and a pair of external electrodes 130a, 130b that are disposed so as to cover the insulating layers 120a, 120b. The solid-state battery 100 is a stacked-type solid-state battery configured such that electrode layers 111 (a positive electrode layer 111a and a negative electrode layer 111b) and solid electrolyte layers 112 that constitute battery structural units are stacked on top of each other, and these layers are made of, for example, fired bodies.

[0023] In this specification, the term "solid-state battery" refers in a broad sense to a battery whose components are made of solids, and in a narrow sense to an all-solid-state battery whose components (particularly preferably all components) are made of solids. Examples of the solid-state battery 100 include so-called secondary batteries (more specifically, storage batteries) that can be repeatedly charged and discharged, and primary batteries that can only be discharged.

[0024] In this specification, the term "pair of external electrodes" refers to external electrodes of different polarities (i.e., positive and negative). In the first embodiment, the pair of external electrodes is composed of one positive first external electrode 130a and one negative second external electrode 130b. However, this is not limited to this, and it is sufficient that there is at least one external electrode of each polarity. For example, in the third embodiment described below, the pair of external electrodes is composed of three positive first external electrodes (see FIG. 4) and three negative second external electrodes (not shown).

[0025] [Battery Element] The battery element 110 has two side surfaces 113a, 113b parallel to the stacking direction and has, for example, a substantially rectangular parallelepiped shape (substantially rectangular parallelepiped shape). The battery element 110 includes a positive electrode layer 111a, a negative electrode layer 111b, and a solid electrolyte layer 112, and further includes an outermost layer 116. The battery element 110 is a laminate in which the positive electrode layers 111a and the negative electrode layers 111b are alternately stacked with the solid electrolyte layer 112 interposed therebetween.

[0026] Outermost layers 116 are arranged facing each other on the outermost sides in the Z direction (stacking direction) of the battery element 110. External electrodes 130a and 130b are arranged on side surfaces 113a and 113b facing each other in the X direction of the battery element 110. End surfaces of the electrode layers 111 (positive electrode layer 111a and negative electrode layer 111b) and the solid electrolyte layer 112 are exposed on side surfaces 113c and 113d facing each other in the Y direction of the battery element 110.

[0027] 1B , on the first side surface 113a side of the solid-state battery 100, the positive electrode layer end surface 111a1 of the positive electrode layer 111a is electrically connected to the first external electrode 130a. Therefore, on the first side surface 113a side of the solid-state battery 100, the positive electrode layer 111a serves as the second electrode layer, the positive electrode layer end surface 111a1 of the positive electrode layer 111a serves as the connection end surface (second end surface) with the first external electrode 130a, and the first external electrode 130a serves as the positive electrode. On the other hand, on the first side surface 113a side of the solid-state battery 100, the negative electrode layer end surface 111b1 of the negative electrode layer 111b is covered by the first insulating layer 120a (the entire negative electrode layer end surface 111b1) and is electrically insulated from the first external electrode 130a. Therefore, on the first side surface 113a side of the solid-state battery 100, the negative electrode layer 111b becomes the first electrode layer, and the negative electrode layer end surface 111b1 of the negative electrode layer 111b becomes the end surface (first end surface) not connected to the first external electrode 130a.

[0028] As shown in the side view of FIG. 2A , on the first side surface 113a side of the solid-state battery 100 in the C1 side view (see FIG. 1A ), the negative electrode layer end surface 111b1 of the negative electrode layer 111b serving as the first electrode layer is entirely covered by the first insulating layer 120a. The positive electrode layer end surface 111a1 of the positive electrode layer 111a is not covered by the first insulating layer 120a and is exposed to the first insulating layer 120a. Furthermore, the first external electrode 130a, which is generally rectangular in side view, is disposed so as to expose the forward Y-direction side and the reverse Y-direction side of the first side surface 113a, covering the upper and lower outermost layers 116, the positive electrode layer end surface 111a1 of the positive electrode layer 111a disposed between the two outermost layers 116, and the negative electrode layer end surface 111b1 of the negative electrode layer 111b, the entire surface of which is covered by the first insulating layer 120a. The first external electrode 130a is in contact with and electrically connected to the positive electrode layer end surface 111a1 of the positive electrode layer 111a, and is electrically insulated from the negative electrode layer end surface 111b1 covered with the first insulating layer 120a.

[0029] 1B , on the second side surface 113b side of the solid-state battery 100, the negative electrode layer end surface 111b1 of the negative electrode layer 111b is electrically connected to the second external electrode 130b. Therefore, on the second side surface 113b side of the solid-state battery 100, the negative electrode layer 111b serves as the second electrode layer, the negative electrode layer end surface 111b1 of the negative electrode layer 111b serves as the connection end surface (second end surface) with the second external electrode 130b, and the second external electrode 130b serves as the negative electrode. On the other hand, on the second side surface 113b side of the solid-state battery 100, the positive electrode layer end surface 111a1 of the positive electrode layer 111a is covered (the entire positive electrode layer end surface 111a1) by the second insulating layer 120b, and is electrically insulated from the second external electrode 130b. Therefore, on the second side surface 113b side of the solid state battery 100, the positive electrode layer 111a becomes the first electrode layer, and the positive electrode layer end surface 111a1 of the positive electrode layer 111a becomes the end surface (first end surface) not connected to the first external electrode 130a.

[0030] As shown in the side view of FIG. 2B , on the second side surface 113b side of the solid-state battery 100 in the C2 side view (see FIG. 1A ), the positive electrode layer end surface 111a1 of the positive electrode layer 111a serving as the first electrode layer is entirely covered by the second insulating layer 120b. The negative electrode layer end surface 111b1 of the negative electrode layer 111b is not covered by the second insulating layer 120b and is exposed to the second insulating layer 120b. Furthermore, the second external electrode 130b, which is generally rectangular in side view, is disposed between the upper and lower outermost layers 116 and the two outermost layers 116, exposing the forward Y-direction side and the reverse Y-direction side of the second side surface 113b, and is disposed to cover the positive electrode layer end surface 111a1 of the positive electrode layer 111a, which is entirely covered by the second insulating layer 120b, and the negative electrode layer end surface 111b1 of the negative electrode layer 111b. The second external electrode 130b contacts and electrically connects to the negative electrode layer end surface 111b1 of the negative electrode layer 111b, and is electrically insulated from the positive electrode layer end surface 111a1 covered with the second insulating layer 120b.

[0031] The solid-state battery 100 satisfies the following mathematical formula (1): [Mathematical Formula 3] W≧W1>W2 (1) [In mathematical formula (1), W represents the width in the extension direction of the first end face, W1 represents the width in the extension direction (of the first end face) of the insulating layer arranged on the first end face, and W2 represents the width in the extension direction (of the first end face) of the external electrode arranged on the insulating layer].

[0032] In the solid-state battery 100 according to the first embodiment, the region used for the determination of the formula (1) is D in FIG. １ Department, D ２ Part and D ３ and part D of FIG. 2B. ４ Part and D ５ This is the part D in FIG. １ This will be explained in detail using the D part of FIG. １ The measurement targets in the area are the negative electrode layer 111b as the first electrode layer, the first insulating layer 120a disposed on the negative electrode layer 111b, and the first external electrode 130a disposed on the first insulating layer 120a. W in Equation (1) is the width of the first end surface (negative electrode layer end surface 111b1) in the extension direction, and D １In the part, W1 corresponds to the length of the negative electrode layer end surface 111b1 in the Y direction. W1 in the formula (1) is the width of the first insulating layer 120a arranged on the negative electrode layer end surface 111b1 in the extension direction (of the negative electrode layer end surface 111b1), and D １ In the part, W2 corresponds to the length of the first insulating layer 120a in the Y direction. W2 in the formula (1) is the width of the first external electrode 130a (of the negative electrode layer end surface 111b1) disposed on the first insulating layer 120a in the extension direction, and D １ In the part, the lengths correspond to the lengths of the first external electrode 130a in the Y direction. Measurements were taken multiple times (number of measurements n=5), and the longest lengths were designated as W, W1, and W2. １ In addition, when the first end surface (negative electrode layer end surface 111b1) is not exposed from the first insulating layer 120a in the Y direction, the length W1 of the first insulating layer 120a in the Y direction is considered to be equal to the width W of the first end surface (negative electrode layer end surface 111b1) in the extension direction.

[0033] D １ In the same manner as in the determination in part D of FIG. ２ Part and D ３ Part D of FIG. ４ Part and D ５ The part D in FIG. ４ The measurement targets in the area are the positive electrode layer 111a as the first electrode layer, the second insulating layer 120b arranged on the positive electrode layer 111a, and the second external electrode 130b arranged on the second insulating layer 120b. W in formula (1) is the width of the first end surface (positive electrode layer end surface 111a1) in the extension direction, and D ４ In the part, W1 corresponds to the length of the positive electrode layer end surface 111a1 in the Y direction. W1 in the formula (1) is the width of the second insulating layer 120b arranged on the positive electrode layer end surface 111a1 in the extension direction (of the positive electrode layer end surface 111a1), and D ４ In the part, W2 corresponds to the length of the second insulating layer 120b in the Y direction. W2 in the formula (1) is the width of the second external electrode 130b arranged on the second insulating layer 120b in the extension direction (of the positive electrode layer end surface 111a1), and D ４In the portion, the length W1 corresponds to the length in the Y direction of the second external electrode 130b. In addition, when the first end face (positive electrode layer end face 111a1) is not exposed from the second insulating layer 120b in the Y direction, the length W1 in the Y direction of the second insulating layer 120b is considered to be equal to the width W in the extension direction of the first end face (positive electrode layer end face 111a1). １ Part ~ D ５ In the first embodiment, the solid-state battery 100 satisfies the formula (1) when all of the D １ Part ~ D ５ In all the portions, W=W1>W2, and the solid-state battery 100 satisfies the formula (1).

[0034] (Electrode Layers: Positive Electrode Layer and Negative Electrode Layer) The positive electrode layer 111a contains a positive electrode active material and may further contain at least one selected from the group consisting of a solid electrolyte, a conductive material, and a sintering aid, and may further include a positive electrode current collecting layer. The negative electrode layer 111b contains at least a negative electrode active material and may further contain at least one selected from the group consisting of a solid electrolyte, a conductive material, and a sintering aid, and may further include a negative electrode current collecting layer. The material constituting the negative electrode layer 111b may be the same as the material constituting the positive electrode layer 111a.

[0035] Active Materials Active materials (positive electrode active materials and negative electrode active materials) are materials involved in the transfer of electrons in the solid-state battery 100. Carriers (ions, particularly lithium ions or sodium ions) move (conduct) between the positive electrode layer 111a and the negative electrode layer 111b via the solid electrolyte, transferring electrons to charge and discharge the battery. The electrode layers 111 (positive electrode layer 111a and negative electrode layer 111b) of the positive electrode layer 111a and the negative electrode layer 111b are preferably layers capable of absorbing and releasing lithium ions or sodium ions, in particular. In other words, the solid-state battery 100 is preferably an all-solid-state secondary battery in which lithium ions or sodium ions move between the positive electrode layer 111a and the negative electrode layer 111b via the solid electrolyte layer 112 to charge and discharge the battery.

[0036] Positive Electrode Active Material Positive electrode active materials capable of absorbing and releasing lithium ions include, for example, at least one selected from the group consisting of lithium-containing phosphate compounds having a Nasicon structure, lithium-containing phosphate compounds having an olivine structure, lithium-containing layered oxides, and lithium-containing oxides having a spinel structure. An example of a lithium-containing phosphate compound having a Nasicon structure is Li3V2(PO4)3. An example of a lithium-containing phosphate compound having an olivine structure is Li3Fe2(PO4)3, LiFePO4, and / or LiMnPO4. An example of a lithium-containing layered oxide is LiCoO2 and / or LiCo 1 / 3 Ni 1 / 3 Mn 1 / 3 Examples of lithium-containing oxides having a spinel structure include LiMnO and / or LiNi. 0.5 Mn 1.5 O4, etc. Examples of lithium compounds include, but are not limited to, lithium transition metal composite oxides and lithium transition metal phosphate compounds. Lithium transition metal composite oxides are oxides containing lithium and one or more transition metal elements as constituent elements. Lithium transition metal phosphate compounds are phosphate compounds containing lithium and one or more transition metal elements as constituent elements. The type of transition metal element is not particularly limited, but examples include cobalt (Co), nickel (Ni), manganese (Mn), and iron (Fe).

[0037] In addition, as the positive electrode active material capable of absorbing and releasing sodium ions, for example, at least one selected from the group consisting of sodium-containing phosphate compounds having a Nasicon structure, sodium-containing phosphate compounds having an olivine structure, sodium-containing layered oxides, and sodium-containing oxides having a spinel structure can be mentioned. ３ V ２ (P.O. ４ ) ３ , NaCoFe ２ (P.O. ４ )３ , Na ２ Ni ２ Fe(PO ４ ) ３ , Na ３ Fe ２ (P.O. ４ ) ３ , Na ２ FeP ２ O ７ and Na ４ Fe ３ (P.O. ４ ) ２ (P ２ O ７ ) and NaFeO as a sodium-containing layered oxide ２ At least one selected from the group consisting of:

[0038] Other examples of the positive electrode active material include oxides, disulfides, and conductive polymers. Examples of oxides include titanium oxide, vanadium oxide, and manganese dioxide. Examples of disulfides include titanium disulfide and molybdenum sulfide. Examples of conductive polymers include disulfides, polypyrrole, polyaniline, polythiophene, polyparastyrene, polyacetylene, and polyacene.

[0039] Negative Electrode Active Material Examples of negative electrode active materials capable of absorbing and releasing lithium ions include at least one selected from the group consisting of oxides containing at least one element selected from the group consisting of titanium (Ti), silicon (Si), tin (Sn), chromium (Cr), iron (Fe), niobium (Nb), and molybdenum (Mo), carbon materials such as graphite, graphite-lithium compounds, lithium alloys, lithium-containing phosphate compounds having a Nasicon structure, lithium-containing phosphate compounds having an olivine structure, and lithium-containing oxides having a spinel structure. An example of a lithium alloy is Li-Al. An example of a lithium-containing phosphate compound having a Nasicon structure is Li3V2(PO4)3 and / or LiTi2(PO4)3. An example of a lithium-containing phosphate compound having an olivine structure is Li3Fe2(PO4)3 and / or LiCuPO4. An example of a lithium-containing oxide having a spinel structure is Li4Ti5O. 12 etc.

[0040] In addition, examples of negative electrode active materials capable of absorbing and releasing sodium ions include at least one selected from the group consisting of sodium-containing phosphate compounds having a Nasicon structure, sodium-containing phosphate compounds having an olivine structure, and sodium-containing oxides having a spinel structure.

[0041] The electrode layer 111 and the solid electrolyte layer 112 preferably have high contrast so that each layer can be easily identified when viewed from the side surface 113 of the battery element 110. This facilitates the formation of the insulating layer 120 on the end surface of the electrode layer 111 in the manufacturing method of the solid battery 100 described below. Such high contrast can be adjusted, for example, by making the compositions of the layers different from each other.

[0042] -Solid Electrolyte- The solid electrolyte that can be contained in the electrode layer 111 may be made of the same material as the solid electrolyte contained in the solid electrolyte layer 112, which will be described later.

[0043] -Conductive Material- Examples of the conductive material include at least one conductive material selected from the group consisting of metal materials such as silver, palladium, gold, platinum, aluminum, copper, and nickel, and carbon.

[0044] -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.

[0045] Current Collector Layers—The current collector layers (positive electrode current collector layer and negative electrode current collector layer) may each have the form of a foil. Here, if it is more important to improve electronic conductivity through co-firing, reduce the manufacturing cost of the solid-state battery 100, and / or reduce the internal resistance of the solid-state battery 100, the current collector layers may have the form of a sintered body. The positive electrode current collector constituting the positive electrode current collector layer and the negative electrode current collector constituting the negative electrode current collector layer are preferably made of a conductive material with high conductivity. Examples of such conductive materials include at least one selected from the group consisting of silver, palladium, gold, platinum, aluminum, copper, and nickel. The current collectors (positive electrode current collector and negative electrode current collector) may have electrical connectors for electrical connection to the outside and may be configured to be electrically connectable to the external electrodes 130a, 130b. When the current collector layers have the form of a sintered body, they may be made of a sintered body containing a conductive material and a sintering aid. The conductive material contained in the current collector layers may be selected from, for example, the same conductive materials that may be contained in the electrode layer 111. The sintering aids contained in the positive electrode current collecting layer and the negative electrode current collecting layer may be selected from, for example, the same materials as the sintering aids that may be contained in the positive electrode layer 111a and the negative electrode layer 111b, respectively.

[0046] The thickness of the positive electrode layer 111a and the negative electrode layer 111b is not particularly limited, but may be, for example, independently 2 μm or more and 200 μm or less, particularly 5 μm or more and 100 μm or less.

[0047] (Solid Electrolyte Layer) The solid electrolyte layer 112 is interposed between the positive electrode layer 111a and the negative electrode layer 111b and is responsible for carrier conduction between these electrode layers. The thickness of the solid electrolyte layer 112 is not particularly limited, but is, for example, 1 μm or more and 500 μm or less, particularly 1 μm or more and 200 μm or less. In this specification, the thickness of the solid electrolyte layer 112 refers to the thickness of the solid electrolyte layer 112 disposed between the positive electrode layer 111a and the negative electrode layer 111b.

[0048] Solid Electrolyte The solid electrolyte layer 112 includes a solid electrolyte and may further include a sintering aid. The solid electrolyte is a material capable of conducting carriers (e.g., lithium ions or sodium ions). In particular, the solid electrolyte layer 112 constituting a battery structural unit in the solid-state battery 100 may form a layer capable of conducting lithium ions between the positive electrode layer 111a and the negative electrode layer 111b. Examples of the solid electrolyte include at least one selected from the group consisting of crystalline solid electrolytes, glass-based solid electrolytes, and glass-ceramic-based solid electrolytes.

[0049] The solid electrolyte capable of conducting lithium ions will be described. Examples of the crystalline solid electrolyte include oxide-based crystalline materials and sulfide-based crystalline materials. Examples of the oxide-based crystalline materials include lithium-containing phosphate compounds having a Nasicon structure, oxides having a perovskite structure, oxides having a garnet structure or a garnet-like structure, and oxide glass ceramic-based lithium ion conductors. Examples of the lithium-containing phosphate compounds having a Nasicon structure include Li ｘ M ｙ (P.O. ４ ) ３ (1≦x≦2, 1≦y≦2, M is at least one selected from the group consisting of titanium (Ti), germanium (Ge), aluminum (Al), gallium (Ga), and zirconium (Zr)). More specifically, Li １．２ Al ０．２ Ti １．８ (P.O. ４ ) ３ Examples of oxides having a perovskite structure include La ０．５５ Li ０．３５ TiO ３Examples of oxides having a garnet-type or garnet-like structure include Li ７ La ３ Zr ２ O １２ etc.

[0050] In addition, sulfide-based crystal materials include thio-LISICON, for example, Li ３．２５ Ge ０．２５ P ０．７５ S ４ and Li １０ GeP ２ S １２ The crystalline solid electrolyte may include a polymer material (for example, polyethylene oxide (PEO)).

[0051] Examples of glass-based solid electrolytes include oxide-based glass materials and sulfide-based glass materials. Examples of oxide-based glass materials include 50Li ４ SiO ４ ・50Li ３ BO ３ Examples of sulfide-based glass materials include 30Li ２ S・26B ２ S ３ ・44LiI, 63Li ２ S・36SiS ２ ・1Li ３ P.O. ４ , 57Li ２ S・38SiS ２ ・5Li ４ SiO ４ , 70Li ２ S・30P ２ S ５ and 50Li ２ S・50GeS ２ Examples include:

[0052] Examples of glass ceramic solid electrolytes include oxide-based glass ceramic materials and sulfide-based glass ceramic materials. Examples of oxide-based glass ceramic materials include a phosphate compound containing lithium, aluminum, and titanium as constituent elements (LATP) and a phosphate compound containing lithium, aluminum, and germanium as constituent elements (LAGP). Examples of LATP include Li, １．０７ Al ０．６９ Ti １．４６ (P.O. ４ ) ３ Examples of LAGP include Li １．５ Al ０．５ Ge １．５ (P.O. ４ ) and the like. Examples of sulfide-based glass ceramic materials include Li ７ P ３ S １１ and Li ３．２５ P ０．９５ S ４ Examples include:

[0053] In addition, examples of solid electrolytes capable of conducting sodium ions include sodium-containing phosphate compounds having a Nasicon structure, oxides having a perovskite structure, and oxides having a garnet or garnet-like structure. Examples of sodium-containing phosphate compounds having a Nasicon structure include Na x M y (PO4)3 (1≦x≦2, 1≦y≦2, M is at least one selected from the group consisting of Ti, Ge, Al, Ga and Zr).

[0054] - Sintering Aid - The sintering aid contained in the solid electrolyte layer 112 may be, for example, the same material as the sintering aid that may be contained in the electrode layers (positive electrode layer 111a and negative electrode layer 111b).

[0055] (Outermost Layers) The outermost layers 116 are arranged facing each other and are outermost in the stacking direction of the battery element 110. The outermost layers 116 protect the layers that contribute to power generation and charging of the battery element 110 (the positive electrode layer 111 a, the negative electrode layer 111 b, and the solid electrolyte layer 112) from the outside, and ensure electrical insulation of the layers that contribute to power generation and charging from the outside.

[0056] [Insulating Layer] The first insulating layer 120a is disposed on the first side surfaces 113a of the battery elements 110, which are parallel to the stacking direction and face each other. The first insulating layer 120a covers the first side surface 113a of the battery element 110 (the negative electrode layer end surface 111b1 thereof and a portion of the solid electrolyte layer end surface 1121 of the solid electrolyte layer 112), and a portion of the first insulating layer 120a is covered by the first external electrode (positive electrode) 130a. In this manner, the first insulating layer 120a is interposed between the first external electrode (positive electrode) 130a and the negative electrode layer 111b of the battery element 110, and insulates the first external electrode 130a from the negative electrode layer 111b of the battery element 110.

[0057] The second insulating layer 120b is disposed on the second side surfaces 113b of the battery element 110, which are parallel to the stacking direction and face each other. The second insulating layer 120b covers the second side surface 113b of the battery element 110 (the positive electrode layer end surface 111a1 thereof and a portion of the solid electrolyte layer end surface 1121 of the solid electrolyte layer 112), and a portion of the second insulating layer 120b is covered by the second external electrode (negative electrode) 130b. In this manner, the second insulating layer 120b is interposed between the second external electrode (negative electrode) 130b and the positive electrode layer 111a of the battery element 110, and insulates the second external electrode 130b from the positive electrode layer 111a of the battery element 110.

[0058] The thickness (length in the X direction) of the insulating layers 120a, 120b is 500 μm or less, 100 μm or less, or 10 μm or less. From the viewpoint of ensuring insulation between the external electrode 130 and the battery element 110, the thickness of the insulating layers 120a, 120b is 5 μm or more, 10 μm or more, or 100 μm or more.

[0059] The insulating layers 120a and 120b contain at least one resin selected from the group consisting of acrylic resin, imide resin, phenolic resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, polyurethane resin, silicon resin (e.g., silicone resin), diallyl phthalate resin, and amino resin.

[0060] [External Electrodes] A pair of external electrodes 130a, 130b are respectively arranged on the mutually opposing side surfaces 113a, 113b of the four side surfaces of the battery element 110 parallel to the stacking direction.

[0061] 2A , on the first side surface 113a of the battery element 110, the first external electrode 130a is electrically connected to the positive electrode layer end surface 111a1 of the positive electrode layer 111a of the battery element 110, and is electrically insulated by the first insulating layer 120a from the negative electrode layer end surface 111b1 of the negative electrode layer 111b of the battery element 110. This makes the first external electrode 130a a positive electrode.

[0062] 2B , on the first side surface 113a of the battery element 110, the second external electrode 130b is electrically connected to the negative electrode layer end surface 111b1 of the negative electrode layer 111b of the battery element 110, and is electrically insulated by the second insulating layer 120b from the positive electrode layer end surface 111a1 of the positive electrode layer 111a of the battery element 110. This makes the second external electrode 130b a negative electrode.

[0063] The external electrodes 130a, 130b are disposed on some, but not all, of the side surfaces 113a, 113b of the battery element 110. More specifically, the first external electrode 130a is disposed so as not to contact the outer edges 114a, 114b of the first side surface 113a that are parallel to the stacking direction in a C1 side view seen from a direction facing the first side surface 113a, and the second external electrode 130b is disposed so as not to contact the outer edges 114a, 114b of the first side surface 113a that are parallel to the stacking direction in a C1 side view seen from a direction facing the second side surface 113b. ２ In side view, the external electrodes 130a, 130b are arranged so as not to contact the outer edges 115a, 115b of the second side surface 113b that are parallel to the stacking direction. When the external electrodes 130a, 130b are arranged so as not to contact the outer edges 114a, 114b, 115a, 115b of the side surfaces 113a, 113b in side view, the external electrodes 130a, 130b are less likely to contact the side surfaces 113c, 113d that are adjacent to the first side surface 113a and on which the electrode layer 111 is exposed. This can further suppress the occurrence of undesired short circuits.

[0064] The external electrode 130 includes, for example, at least one metal selected from the group consisting of silver, gold, platinum, aluminum, copper, tin, carbon, and nickel.

[0065] [Method for manufacturing solid-state battery] A method for manufacturing the solid-state battery 100 according to the first embodiment includes: arranging (forming) an insulating layer on at least a part of a first end surface of a first electrode layer of either the positive electrode layer 111 a or the negative electrode layer 111 b, which is exposed on the side surface 113 of the battery element 110 (insulating layer forming step); and arranging (forming) an external electrode 130 on at least a part of a second end surface of a second electrode layer of the other electrode layer of the positive electrode layer 111 a or the negative electrode layer 111 b, which is exposed on the side surface 113 of the battery element 110 (external electrode forming step).

[0066] One aspect of a method for manufacturing the solid-state battery 100 according to the first embodiment will be described with reference to Figures 8, 9, and 10. Figures 8 to 10 are perspective views that schematically illustrate steps in a manufacturing process for the solid-state battery according to the first embodiment of the present disclosure. Note that, unless otherwise noted, the manufacturing of the solid-state battery 100 was carried out at room temperature (25°C), atmospheric pressure (1 atm), and in an open system.

[0067] For example, the manufacturing method of the solid-state battery 100 may further include preparing the battery element 110 (a battery element preparation step). In this specification, the positive electrode side will be described as a representative example. The negative electrode side is substantially the same as the positive electrode side except that the lead-out portion is connected to the connection end surface of the negative electrode layer, and therefore, a description thereof will be omitted.

[0068] (Battery Element Preparation Step) In the battery element preparation step, the battery element 110 is prepared by, for example, manufacturing or purchasing.

[0069] (Insulating Layer Forming Process) In the insulating layer forming process, the first insulating layer 120a is formed using, for example, an inkjet process so as to completely cover the negative electrode layer end surface 111b1 of the negative electrode layer 111b exposed on the first side surface 113a of the battery element 110. The inkjet process forms the insulating layer 120 directly on the side surface 113 of the battery element 110, and therefore has higher positional accuracy than, for example, the method described in Patent Document 2, in which an insulating member is first placed on a substrate and then the substrate is bonded to the side surface of the battery element, thereby placing an insulating member on the battery element. This makes it possible to more effectively prevent undesired short circuits between the external electrodes and the electrode layers.

[0070] (External electrode forming process) In the external electrode forming process, the first external electrode 130a is formed on a part of the first side surface 113a. Here, the first external electrode 130a is arranged so that the forward Y direction side and the reverse Y direction side are exposed in the C1 side view, and so as to cover the outermost layer 116, the positive electrode layer end surface 111a1 of the positive electrode layer 111a, and the negative electrode layer end surface 111b1 of the negative electrode layer 111b covered with the first insulating layer 120a.

[0071] Specific methods for forming the external electrodes include, for example, inkjet processing and printing using a metal mask. Printing using a metal mask will be described with reference to FIG. 9 . As shown in FIG. 9 , a metal mask 500 has a substantially rectangular first opening 520 in a metal substrate 510. The substantially rectangular shape of this first opening 520 corresponds to the shape of the first external electrode 130a in a C1 side view. The battery element 110 is placed in the first opening 520 of the metal mask 500. This battery element 110 has already undergone an insulating layer formation process, and a first insulating layer 120a has already been formed on the first side surface 113a. In this state, a first external electrode precursor material 130apr is poured through the first opening 520 to form a coating film of the first external electrode precursor material 130apr on the first side surface 113a. The coating film is then dried. This forms the first external electrode 130a on the first side surface 113a of the battery element 110.

[0072] As shown in Fig. 10 , the first opening 520 in Fig. 9 is an opening for forming the first external electrode 130a on the first side surface 113a of the singulated battery element. Meanwhile, the second opening 530 in Fig. 9 is an opening for forming the first external electrode 130a on the first side surface 113a of the singulated battery element 110 or the strip-shaped battery element 110 (see Fig. 8 : right side view), as shown in Fig. 10 . Note that strip-shaped battery elements 110 may also be used in the insulating layer formation step. In this case, the end surfaces of the electrode layer 111 and solid electrolyte layer that form the first external electrode 130a must be exposed in the insulating layer formation step and the external electrode formation step.

[0073] Second Embodiment: Solid-State Battery The solid-state battery according to the second embodiment differs from the solid-state battery 100 according to the first embodiment in that W>W1 in formula (1). This different configuration will be mainly described below. Note that in the second embodiment, the same reference numerals as in the first embodiment represent the same configuration as in the first embodiment, and therefore, in principle, description thereof will be omitted.

[0074] [Configuration of Solid-State Battery] The configuration of the insulating layer in a side view will be described with reference to Fig. 3. Fig. 3 is a side view schematically showing the configuration of a solid-state battery 100A according to a second embodiment. Note that in the second embodiment, the first insulating layer 120Aa in a C1 side view will be described as an example. A description of the second insulating layer in a C2 side view will be omitted.

[0075] 3, in side view C1, a portion of the end surface 110b1 (first end surface) of the anode layer 111b is covered with the first insulating layer 120Aa. More specifically, the first insulating layer 120Aa covers a portion of the end surface 110b1 of the anode layer 111b, and a portion of the anode layer end surface 111b1 of the anode layer 111b is exposed. In the solid state battery 100A according to the second embodiment, the relationship W > W1 > W2 in formula (1) is satisfied.

[0076] The first insulating layer 120Aa separates the first external electrode 130a and the negative electrode layer 111b by a width (length in the Y direction) L Ａ The first insulating layer 120Aa is spaced apart in the extension direction (Y direction) of the first end face by a distance L in the Y direction, thereby ensuring insulation between the first external electrode 130a and the negative electrode layer 111b. In this way, the first insulating layer 120Aa covers a part of the negative electrode layer end face 111b1 of the negative electrode layer 111b, thereby ensuring insulation between the first external electrode 130a and the negative electrode layer 111b, thereby making it possible to reduce the size and weight, reduce material costs, and prevent short circuits between the first external electrode 130a and the electrode layer (negative electrode layer 111b) exposed on the side faces 113c and 113d. Ａ ) is, for example, 10 μm or more and 200 μm or less.

[0077] [Method of Manufacturing Solid-State Battery] The method of manufacturing the solid-state battery 100A according to the second embodiment is the same as that of the first embodiment, except that the arrangement pattern of the first insulating layer 120a on the first side surface 113a is changed from the entire anode layer end surface 111b1 and a part of the solid electrolyte layer end surface 1121 of the adjacent solid electrolyte layer 112 to a part of the anode layer end surface 111b1 and a part of the solid electrolyte layer end surface 1121 of the adjacent solid electrolyte layer 112, and the arrangement pattern of the second insulating layer (not shown) on the second side surface 113b is changed from the entire cathode layer end surface 111a1 and a part of the solid electrolyte layer end surface 1121 of the adjacent solid electrolyte layer 112 to a part of the cathode layer end surface 111a1 and a part of the solid electrolyte layer end surface 1121 of the adjacent solid electrolyte layer 112.

[0078] <Third Embodiment: Solid-State Battery> The solid-state battery according to the third embodiment differs from the solid-state battery 100 according to the first embodiment in that a plurality of external electrodes of the same type are arranged on the same side surface. Arranging a plurality of external electrodes of the same type on the same side surface means arranging a plurality of electrodes of the same polarity (e.g., positive or negative electrodes) on the same side surface. This different configuration will be mainly described below. Note that in the third embodiment, the same reference numerals as those in the first embodiment represent the same configuration as in the first embodiment, and therefore, in principle, description thereof will be omitted.

[0079] [Configuration of Solid-State Battery] The configuration of the first external electrode 130Ba in the C1 side view will be described with reference to Fig. 4. Fig. 4 is a side view schematically showing the configuration of the solid-state battery 100B according to the third embodiment. Note that the third embodiment will be described using the first external electrode 130Ba in the C1 side view as an example. A description of the second external electrode in the C2 side view will be omitted.

[0080] As shown in FIG. 4 , a plurality of external electrodes 130Ba of the same polarity (same type) among the pair of external electrodes are arranged on the same side surface. More specifically, three first external electrodes (positive electrodes) 130Ba are arranged on the first side surface 113a. Each first external electrode 130Ba has a substantially rectangular shape with its major axis in the Z direction, and the three first external electrodes 130Ba are arranged parallel to the Z direction and equally spaced apart in the Y direction. When a plurality of first external electrodes 130Ba are formed on the first side surface 113a, even if one of these first external electrodes 130Ba peels off, the remaining first external electrodes 130Ba can maintain conduction with the electrode layer 111 (positive electrode layer 111a).

[0081] In the third embodiment, the determination of whether formula (1) is satisfied is performed for the first external electrodes 130Ba located relatively farthest to the right and farthest to the left. In FIG. 4, since there are three first insulating layers 120a, it is determined whether formula (1) is satisfied for all six locations on the first side surface 113a. Although not shown, it is determined whether formula (1) is satisfied for all four locations on the second side surface 113b.

[0082] [Method for Manufacturing Solid-State Battery] The method for manufacturing a solid-state battery according to the third embodiment is similar to that according to the first embodiment, except for the following changes. The method for manufacturing a solid-state battery 100B according to the third embodiment will be described with reference to FIG. 11 . FIG. 11 is a perspective view schematically illustrating the manufacturing process of the solid-state battery 100B according to the third embodiment. As shown in FIG. 11 , a metal mask 500B is formed with a plurality of rectangular first openings (slits) 520B. The opening shape of the first openings 520B corresponds to the shape of the first external electrode 130Ba in a C1 side view. As in FIGS. 9 and 10 , the battery element 110 is placed in the first openings 520B of the metal mask 500B, and the first external electrode precursor material is poured out of the first openings 520B to form a coating film of the external electrode precursor material on the first side surface 113a of the battery element 110. The coating film is then dried to form the first external electrode 130Ba. The second opening 530B on the left side of Figure 11 is an opening for forming the first external electrode 130Ba on the strip-shaped battery element (see Figure 8: right diagram), and the first opening 520B on the right side of Figure 11 is an opening for forming the first external electrode 130Ba on the individualized battery element 110.

[0083] <Fourth embodiment: solid-state battery> The solid-state battery according to the fourth embodiment differs from the solid-state battery 100 according to the first embodiment in that two types of external electrodes are arranged on one side surface. This different configuration will be mainly described below. In the fourth embodiment, the same reference numerals as those in the first embodiment represent the same configuration as in the first embodiment, and therefore, in principle, description thereof will be omitted.

[0084] [Configuration of Solid-State Battery] The configuration of the first external electrode 130Ca and the second external electrode 130Cb in a C1 side view will be described with reference to FIG. 5 . FIG. 5 is a side view schematically illustrating the configuration of the solid-state battery 100C according to the fourth embodiment. As shown in FIG. 5 , two types of external electrodes (the first external electrode 130Ca (positive electrode) and the second external electrode 130Cb (negative electrode)) are arranged on the first side surface 113a of the solid-state battery 100C according to the fourth embodiment. The first side surface 113a of the solid-state battery 100C is divided into a first external electrode region Aa on the relatively left side and a second external electrode region Ab on the relatively right side with respect to a line parallel to the Z direction that passes through the middle in the Y direction.

[0085] In the first external electrode region Aa, the negative electrode layer end surface 111b1 (corresponding to the first end surface of the first electrode) of the negative electrode layer 111b is covered with the first insulating layer 120Ca, and the positive electrode layer end surface 111a1 (corresponding to the second end surface of the second electrode) of the positive electrode layer 111a is exposed from the first insulating layer 120Ca. The first external electrode 130Ca is electrically connected to the positive electrode layer end surface 111a1 of the positive electrode layer 111a and electrically insulated from the negative electrode layer end surface 111b1 of the negative electrode layer 111b. Therefore, the first external electrode 130Ca in the first external electrode region Aa is a positive electrode. The width of the first external electrode region Aa in the X direction corresponds to the width W1 in the extension direction of the first insulating layer.

[0086] In the second external electrode region Ab, the positive electrode layer end surface 111a1 (corresponding to the first end surface of the first electrode) of the positive electrode layer 111a is covered with the second insulating layer 120Cb, and the negative electrode layer end surface 111b1 of the negative electrode layer 111b is exposed from the second insulating layer 120Cb. The second external electrode 130Cb is electrically connected to the negative electrode layer end surface 111b1 (corresponding to the second end surface of the second electrode) of the negative electrode layer 111b and electrically insulated from the positive electrode layer end surface 111a1 of the positive electrode layer 111a. Therefore, the second external electrode 130Cb in the second external electrode region Ab is a negative electrode. The width of the second external electrode region Ab in the X direction corresponds to the width W1 in the extension direction of the second insulating layer.

[0087] External electrodes 130Ca and 130Cb of different polarities are arranged on the same side, and the semiconductor device has a first external electrode region (first region) Aa on the same side where one (polarity) first external electrode 130Ca is arranged, and a second external electrode region (second region) Ab on the same side where the other (polarity) second external electrode 130Cb is arranged, and the first insulating layer 120Ca in the first external electrode region Aa and the second insulating layer 120Cb in the second external electrode region Ab are arranged alternately in the stacking direction. More specifically, a pair of external electrodes 130Ca, 130Cb are arranged on the same side, that is, the first side surface 113a, and a first external electrode region (first region) Aa on the same side surface 113a on which one first external electrode 130Ca is arranged and a second external electrode region (second region) Ab on the same side surface 113a on which the other second external electrode 130Cb is arranged are adjacent to each other via a linear interface, and the first insulating layer 120Ca and the second insulating layer 120Cb are arranged alternately at the interface.

[0088] In this way, the pair of external electrodes 130Ca, 130Cb are arranged on the same side surface 113a among the four side surfaces 113a, 113b, 113c, and 113d parallel to the stacking direction of the battery element 110. Note that in the fourth embodiment, the first external electrode region Aa and the second external electrode region Ab are adjacent to each other with an interface therebetween, but this is not limiting. For example, the first external electrode region Aa and the second external electrode region Ab may partially overlap, or the first external electrode region Aa and the second external electrode region Ab may be spaced apart from each other.

[0089] 5, in the fourth embodiment, the formula (1) is evaluated at three locations for the first external electrode 130Ca and at two locations for the first external electrode 130Ca, and it is determined whether the formula (1) is satisfied for all five locations in total.

[0090] [Method for Manufacturing Solid State Battery] The method for manufacturing a solid state battery according to the fourth embodiment is the same as that of the first embodiment, except that the insulating layer forming step and the external electrode formation step are changed as described below.

[0091] (Insulating Layer Forming Process) In the insulating layer forming process, the first insulating layer 120Ca is formed by, for example, an inkjet method so as to cover the entire negative electrode layer end surface 111b1 of the negative electrode layer 111b exposed in the first external electrode region Aa of the first side surface 113a of the battery element 110. Furthermore, the second insulating layer 120Cb is formed by, for example, an inkjet method so as to cover the entire positive electrode layer end surface 111a1 of the positive electrode layer 111a exposed in the second external electrode region Ab of the first side surface 113a of the battery element 110.

[0092] (External electrode forming process) In the external electrode forming process, the first external electrode 130Ca is formed in the first external electrode region Aa of the first side surface 113a, and the second external electrode 130Cb is formed in the second external electrode region Ab of the first side surface 113a. The first external electrode 130Ca is formed in the first external electrode region Aa of the first side surface 113a so as to cover the upper and lower outermost layers 116 and the positive electrode layer end surface 111a1 of the positive electrode layer 111a and the negative electrode layer end surface 111b1 of the negative electrode layer 111b covered with the first insulating layer 120Ca, so that the forward Y direction and reverse Y direction of the first external electrode region Aa are exposed.

[0093] The second external electrode 130Cb is formed in the second external electrode region Ab of the first side surface 113a so as to cover the upper and lower outermost layers 116 and the positive electrode layer end surface 111a1 of the positive electrode layer 111a and the negative electrode layer end surface 111b1 of the negative electrode layer 111b, which are covered with the second insulating layer 120Cb, arranged therebetween, so that the forward Y direction and reverse Y direction of the second external electrode region Ab are exposed.

[0094] Fifth Embodiment: Solid-State Battery The solid-state battery according to the fifth embodiment differs from the solid-state battery 100 according to the first embodiment in that it further includes a composite exterior part and an extraction electrode. This different configuration will be mainly described below. In the fifth embodiment, the same reference numerals as those in the first embodiment represent the same configuration as in the first embodiment, and therefore, in principle, description thereof will be omitted.

[0095] A solid-state battery according to the fifth embodiment will be described with reference to Fig. 6. Fig. 6 is a cross-sectional view schematically showing the configuration of the solid-state battery according to the fifth embodiment.

[0096] As shown in FIG. 6 , the solid-state battery 100D according to the fifth embodiment further includes composite exterior parts 150a, 150b that cover and seal the battery element 110 and the pair of external electrodes 130a, 130b, and extraction electrodes 140a, 140b that are electrically connected to the pair of external electrodes 130a, 130b and can extract electricity to the outside.

[0097] The solid-state battery 100D according to the fifth embodiment further includes composite exterior parts 150a, 150b and lead electrodes 140a, 140b in addition to the solid-state battery 100 according to the first embodiment. In the solid-state battery 100 according to the first embodiment, the end faces of the positive electrode layer 111a, the negative electrode layer 111b, and the solid electrolyte layer 112 are exposed to the outside on two side surfaces 113c, 113d parallel to the stacking direction. Therefore, the solid-state battery 100D is sealed with the composite exterior parts 150a, 150b, which have excellent moisture resistance, thereby suppressing the penetration of moisture from the atmosphere into the battery element 110.

[0098] (Composite Exterior Portion) The composite exterior portions 150a and 150b cover and seal the battery element 110 and the pair of external electrodes 130a and 130b.

[0099] As shown in Fig. 6, the first composite exterior part 150a covers the side surfaces 113a, 113b and bottom surface 113f (as well as side surfaces 113c, 113d (not shown in Fig. 6)) of the solid-state battery 100. The second composite exterior part 150b covers the side surfaces 113a, 113b of the solid-state battery via the first composite exterior part 150a and the lead-out electrodes 140a, 140b, and further partially covers the top surface 113e of the solid-state battery 100 via the lead-out electrodes 140a, 140b.

[0100] Here, the layer structure of the first composite exterior part 150a will be described as an example. The second composite exterior part 150b has the same structure as the first composite exterior part 150a, and therefore will not be described here. The first composite exterior part 150a includes, from the side relatively closer to the battery element 110 to the side relatively farther from it, a first adhesive layer 150a1, a first metal layer 150a2 disposed on the first adhesive layer 150a1, and a first protective layer 150a3 disposed on the first metal layer 150a2. The first adhesive layer 150a1 functions to adhere the first composite exterior part 150a to the object to be sealed. The first adhesive layer 150a1 includes, for example, an epoxy resin. The first metal layer 150a2 includes a metal, such as a metal foil. Examples of metals include Al, Cu, Ni, and alloys (more specifically, SUS (stainless steel)). Therefore, the first metal layer 150a2 is less permeable to moisture and provides moisture resistance to the first composite exterior part 150a. The first protective layer 150a3 contains a resin (e.g., epoxy resin) and is, for example, a resin film.

[0101] (Extraction Electrodes) The extraction electrodes 140a, 140b are electrically connected to the pair of external electrodes 130a, 130b and can extract electricity to the outside (i.e., the solid state battery 100D can be electrically connected to an external component). The first extraction electrode 140a is disposed on the upper surface 113e, is connected to the first external electrode 130a, and extends to the outside between the first composite exterior part 150a and the second composite exterior part 150b. The second extraction electrode 140b is disposed on the upper surface 113e, is connected to the second external electrode 130b, and extends to the outside between the first composite exterior part 150a and the second composite exterior part 150b.

[0102] [Method for manufacturing solid-state battery] The method for manufacturing a solid-state battery according to the fifth embodiment includes the method for manufacturing a solid-state battery according to the first embodiment, and further includes sealing with a composite exterior part (composite exterior part sealing step).

[0103] (Composite Exterior Sealing Process) In the composite exterior sealing process, the composite exterior parts 150a and 150b are used for sealing. Specifically, the first composite exterior part 150a is first bonded to the battery element 110 so as to cover the lower surface 113f and side surfaces 113a and 113b (and side surfaces 113c and 113d) of the battery element 110 and the external electrodes 130a and 130b. Next, the lead electrodes 140a and 140b are placed on the upper surface 113e of the battery element 110 so as to be electrically connected to the external electrodes 130a and 130b, and are also placed in contact with the first protective layer 150a3 of the first composite exterior part 150a. Next, the second composite exterior part 150b is placed in contact with the lead electrodes 140a and 140b, thereby sealing the battery element 110 and the external electrodes 130a and 130b with the composite exterior parts 150a and 150b. In this manner, the solid state battery 100D is manufactured.

[0104] <Sixth Embodiment: Solid-State Battery Package> A solid-state battery package according to the sixth embodiment includes the solid-state battery according to the first embodiment. In the sixth embodiment, the same reference numerals as those in the first embodiment have the same configuration as those in the first embodiment, and therefore, in principle, their description will be omitted. The solid-state battery package according to the sixth embodiment will be described with reference to Fig. 7. Fig. 7 is a cross-sectional view schematically showing the configuration of a solid-state battery package according to a seventh embodiment of the present disclosure.

[0105] The solid-state battery package 1000 includes: the solid-state battery 100 according to the first embodiment; a circuit board 200 having the solid-state battery 100 mounted thereon and a circuit 210 electrically connected to the external electrodes 130 a, 130 b; and an exterior body 400 that covers and seals the solid-state battery 100 via a sealing layer 300.

[0106] In the solid-state battery package 1000, the solid-state battery 100 mounted on the circuit board 200 is sealed with a sealing layer 300, and the sealing layer 300 is further covered with an exterior body 400. In this way, the solid-state battery 100 is covered by the circuit board 200, the sealing layer 300, and the exterior body 400, and therefore is not exposed to the outside and is protected from the outside. In the solid-state battery 100 according to the first embodiment, end faces of the positive electrode layer 111a, the negative electrode layer 111b, and the solid electrolyte layer 112 are exposed to the outside on two side surfaces 113c, 113d parallel to the stacking direction. Therefore, by sealing the solid-state battery 100 with the sealing layer 300 and covering it with the exterior body 400, the penetration of moisture from the atmosphere into the battery element 110 is suppressed.

[0107] (Circuit Board) The circuit board 200 mounts (places and fixes) the solid-state battery 100 on a first surface 202. The circuit board 200 has a circuit 210 with terminals exposed on a first surface (the surface on which the solid-state battery is mounted) 212, and external terminals 220 electrically connected to the circuit 210 on a second surface 204 opposite the first surface 202. Therefore, by mounting the solid-state battery 100 on the circuit board 200, the external electrodes 130a, 130b are electrically connected to the terminals of the circuit 210. This electrically connects the external electrodes 130a, 130b of the solid-state battery 100 to the external terminals 220 of the circuit board 200. As a result, the solid-state battery 100 in the solid-state battery package 1000 is electrically connected to other components outside the solid-state battery package 1000.

[0108] (Sealing Layer) The sealing layer 300 seals the solid-state battery 100 mounted on the circuit board 200. As a result, the solid-state battery 100 is sealed by the sealing layer 300 except for the bottom surface 113f of the battery element 110. The sealing layer 300 has insulating properties and electrically insulates the outer surface of the solid-state battery 100 from the inner surface of the exterior body 400. The sealing layer 300 includes, for example, a resin.

[0109] (Exterior Body) The exterior body 400 covers and seals the solid-state battery 100 via the sealing layer 300. The exterior body 400 includes, for example, a metal. In this case, the exterior body 400 is a metal exterior body made of metal. Metal is less permeable to moisture, so the metal exterior body has excellent moisture resistance.

[0110] [Method for manufacturing a solid-state battery] The method for manufacturing a solid-state battery package according to the sixth embodiment includes the method for manufacturing a solid-state battery according to the first embodiment, plus a solid-state battery mounting step, an insulating layer covering step, and an exterior body covering step.

[0111] (Solid-state battery mounting process) In the solid-state battery mounting process, the solid-state battery 100 is mounted (placed and fixed) on the circuit board 200, for example, by soldering. By mounting the solid-state battery 100 on the circuit board 200, the external electrodes 130a, 130b of the solid-state battery 100 and the terminals of the circuit 210 arranged on the first surface 202 of the circuit board 200 are electrically connected.

[0112] (Sealing Layer Coating Process) In the sealing layer coating process, the solid state battery 100 mounted on the circuit board 200 is coated with a sealing layer 300. As a result, the solid state battery 100 is not exposed to the outside (e.g., the atmosphere) and is isolated from the outside, and further is electrically insulated from everything except the terminals provided on the first surface 202 of the circuit board 200. Specifically, when the sealing layer 300 is made of resin, the sealing layer 300 can be formed by a dipping method.

[0113] (Exterior Body Covering Process) In the exterior body covering process, the solid state battery 100 covered with the sealing layer 300 is further covered with the exterior body 400. Specifically, in the exterior body covering process, the solid state battery 100 is covered with the exterior body 400 via the sealing layer 300, and is joined to the side surface and the second surface 204 of the circuit board 200. In this manner, the solid state battery package 1000 is manufactured.

[0114] Other Embodiments Although the embodiments of the present disclosure have been described above, the above-described embodiments are merely exemplary examples. Therefore, it will be readily understood by those skilled in the art that the present disclosure is not limited to the above-described embodiments, and that various aspects, such as design modifications and combinations of embodiments, are possible within the scope of the gist of the present disclosure.

[0115] For example, in the first to third embodiments, two external electrodes are arranged on the side surfaces 113a and 113b that are parallel to the stacking direction of the substantially rectangular parallelepiped battery element 110 and that face each other, but this is not limiting. For example, a pair of external electrodes may be arranged on each of adjacent side surfaces among the four side surfaces 113a, 113b, 113c, and 113d that are parallel to the stacking direction of the substantially rectangular parallelepiped battery element 110.

[0116] In the first to third embodiments, insulating layers and external electrodes of the same shape are arranged on the side surfaces 113a and 113b, respectively, but this is not limiting. For example, the first embodiment and the second embodiment may be combined. More specifically, the first insulating layer 120Aa and the first external electrode 130a of the second embodiment or the first insulating layer 120a and the first external electrode 130Ba of the third embodiment may be arranged on the first side surface 113a, and the second insulating layer 120b and the second external electrode 130b of the first embodiment may be arranged on the second side surface 113b.

[0117] In this way, the two types of external electrodes (positive and negative electrodes) can be arranged not only on two mutually opposing side surfaces of the substantially rectangular parallelepiped battery element 110 of the first to third embodiments, but also on the same side surface as shown in the fourth embodiment, and can also be arranged on the adjacent side surfaces described above. In other words, the solid-state battery according to the present disclosure allows the location of the external electrodes to be selected depending on the application of the solid-state battery, and thus provides a high degree of freedom in design.

[0118] In addition, in the fifth embodiment, the solid-state battery according to the first embodiment further includes composite exterior parts 150 a, 150 b and lead electrodes 140 a, 140 b, but is not limited to this. For example, in the fifth embodiment, the solid-state battery according to the second, third, or fourth embodiment may be used instead of the solid-state battery according to the first embodiment.

[0119] Furthermore, the solid-state battery package according to the sixth embodiment includes the solid-state battery according to the first embodiment, but is not limited to this. For example, the fifth embodiment may include the solid-state battery according to the second, third, or fourth embodiment instead of the solid-state battery according to the first embodiment.

[0120] A solid ionization package according to the present disclosure is as follows: <1> A solid-state battery comprising: a battery element in which positive electrode layers and negative electrode layers are alternately stacked with solid electrolyte layers interposed therebetween, the positive electrode layers and the negative electrode layers are exposed, and the battery element has at least one side surface parallel to the stacking direction; an insulating layer arranged to cover at least a portion of a first end surface of a first electrode layer of one of the positive electrode layers and the negative electrode layers exposed at the side surface; and an external electrode arranged on a portion of the side surface to cover a second end surface of a second electrode layer of the other of the positive electrode layers and the negative electrode layers exposed at the side surface and the insulating layer, wherein the solid-state battery satisfies the following formula (1): [Formula 4] W≧W1>W2 (1) [in formula (1), W represents the width in the extension direction of the first end surface, W1 represents the width in the extension direction of the insulating layer arranged on the first end surface, and W2 represents the width in the extension direction of the external electrode arranged on the insulating layer]. <2> The solid-state battery according to <1>, wherein the external electrodes are arranged so as not to contact outer edges of the side surfaces that are parallel to the stacking direction in a side view seen from a direction facing the side surfaces. <3> The solid-state battery according to <1> or <2>, wherein W = W1 in formula (1). <4> The solid-state battery according to any one of <1> to <3>, wherein a portion of the first end surface is covered with the insulating layer. <5> The solid-state battery according to any one of <1> to <4>, wherein W > W1 in formula (1). <6> The solid-state battery according to any one of <1> to <5>, wherein a plurality of the external electrodes having the same polarity are arranged on the same side surface. <7> The solid-state battery according to any one of <1> to <6>, wherein the external electrodes of different polarities are arranged on the same side surface, and the battery has a first region on the same side surface where one external electrode is arranged and a second region on the same side surface where the other external electrode is arranged, and the first insulating layer in the first region and the second insulating layer in the second region are arranged alternately in the stacking direction. <8> The solid-state battery according to any one of <1> to <7>, wherein the battery element has a substantially rectangular parallelepiped shape, and the front external electrode is arranged on the same side surface, an adjacent side surface, or an opposing side surface among four side surfaces of the battery element parallel to the stacking direction.<9> The solid-state battery according to any one of <1> to <8>, further comprising: a composite exterior part that covers and seals the battery element and the external electrodes; and an extraction electrode that is electrically connected to the external electrodes and is capable of extracting electricity to the outside. <10> A solid-state battery package comprising: the solid-state battery according to any one of <1> to <9>; a circuit board that mounts the solid-state battery and has a circuit that is electrically connected to the external electrodes; and an exterior body that covers and seals the solid-state battery via a sealing layer. <11> A method for producing the solid-state battery according to any one of <1> to <9>, comprising: arranging an insulating layer on at least a part of a first end surface of a first electrode layer of one of the positive electrode layer and the negative electrode layer, the first end surface being exposed at a side surface of the battery element; and arranging an external electrode on at least a part of a second end surface of a second electrode layer of the other of the positive electrode layer and the negative electrode layer, the second end surface being exposed at the side surface of the battery element. <12> The method for manufacturing a solid-state battery according to <11>, wherein the insulating layer is disposed using an inkjet method.

[0121] The solid-state battery according to the present disclosure can be used in applications that typically require the use of electrical energy. For example, the solid-state battery according to the present disclosure can be used in various fields where power storage is anticipated. Although merely illustrative, the battery according to the present disclosure can be used in the electrical, information, and communications fields where electrical and electronic devices are used (for example, the electrical and electronic device fields or mobile device fields including mobile phones, smartphones, laptop computers, digital cameras, activity monitors, arm computers, electronic paper, wearable devices, and small electronic devices such as RFID tags, card-type electronic money, and smart watches), household and small industrial applications (for example, power tools, golf carts, and household, nursing care, and industrial robots), large industrial applications (for example, forklifts, elevators, and port cranes), transportation systems (for example, hybrid cars, electric cars, buses, trains, electrically assisted bicycles, and electric motorcycles), power system applications (for example, various power generation systems, road conditioners, smart grids, and general household installation-type power storage systems), medical applications (medical devices such as earphone hearing aids), pharmaceutical applications (dose management systems), as well as the IoT field, and space and deep-sea applications (for example, space probes, submersible research vessels, and the like).

[0122] 100, 100A, 100B, 100C, 100D Solid-state battery 110 Battery element (laminated body) 111 Electrode layer 111a Positive electrode layer 111a1 Positive electrode layer end surface 111b Negative electrode layer 111b1 Negative electrode layer end surface 112 Solid electrolyte layer 1121 Solid electrolyte layer end surface 113a First side surface 113b Second side surface 113c Third side surface 113d Fourth side surface 113e Upper surface (top surface) 113f Lower surface (bottom surface) 114a, 114b Outer edge parallel to the stacking direction in C1 side view 115a, 115b Outer edge parallel to the stacking direction in C2 side view 116 Outermost layer 120a, 120Aa, 120Ca First insulating layer 120b, 120Cb Second insulating layer 130a, 130Ba, 130Ca First external electrode 130b, 130Cb Second external electrode 140a First lead electrode 140b Second lead electrode 150a First composite exterior part 150a1 First adhesive layer 150a2 First metal layer 150a3 First protective layer 150b Second composite exterior part 150b1 Second adhesive layer 150b2 Second metal layer 150b3 Second protective layer 200 Circuit board 202 First surface 204 Second surface 210 Circuit 220 External terminal 300 Sealing layer 400 Exterior body 1000 Solid-state battery package W Width in the extension direction of the first end surface W1 Width in the extension direction of the insulating layer arranged on the first end surface W2 Width in the extension direction of the external electrode arranged on the insulating layer

Claims

1. A solid-state battery comprising: a battery element in which positive electrode layers and negative electrode layers are alternately stacked with solid electrolyte layers interposed therebetween, the positive electrode layers and the negative electrode layers being exposed, and the battery element having at least one side surface parallel to the stacking direction; an insulating layer arranged so as to cover at least a portion of a first end surface of a first electrode layer of one of the positive electrode layers or the negative electrode layers exposed at the side surface; and an external electrode arranged on a portion of the side surface so as to cover a second end surface of a second electrode layer of the other of the positive electrode layers or the negative electrode layers exposed at the side surface and the insulating layer, wherein the battery element satisfies the following mathematical expression (1): [Mathematical Expression 1] W≧W1>W2 (1) [In mathematical expression (1), W represents the width in the extension direction of the first end surface, W1 represents the width in the extension direction of the insulating layer arranged on the first end surface, and W2 represents the width in the extension direction of the external electrode arranged on the insulating layer].

2. The solid-state battery according to claim 1, wherein the external electrodes are arranged so as not to contact the outer edges of the side surfaces that are parallel to the stacking direction when viewed from the side facing the side surfaces.

3. The solid-state battery according to claim 1 or 2, wherein W=W1 in formula (1).

4. The solid-state battery according to any one of claims 1 to 3, wherein a portion of the first end surface is covered with the insulating layer.

5. The solid-state battery according to any one of claims 1 to 4, wherein W>W1 in formula (1).

6. A solid-state battery according to any one of claims 1 to 5, wherein a plurality of the external electrodes having the same polarity are arranged on the same side surface.

7. A solid-state battery according to any one of claims 1 to 6, wherein the external electrodes of different polarities are arranged on the same side, the battery has a first region on the same side where one external electrode is arranged, and a second region on the same side where the other external electrode is arranged, and the first insulating layer in the first region and the second insulating layer in the second region are arranged alternately in the stacking direction.

8. The solid-state battery according to any one of claims 1 to 7, wherein the battery element has a substantially rectangular parallelepiped shape, and the external electrodes are disposed on the same side, an adjacent side, or an opposing side among four side surfaces of the battery element that are parallel to the stacking direction.

9. The solid-state battery according to any one of claims 1 to 8, further comprising: a composite exterior part that covers and seals the battery element and the external electrode; and an extraction electrode that is electrically connected to the external electrode and is capable of extracting electricity to the outside.

10. A solid-state battery package comprising: a solid-state battery according to any one of claims 1 to 9; a circuit board on which said solid-state battery is mounted and which has a circuit electrically connected to said external electrodes; and an exterior body which covers and seals said solid-state battery via a sealing layer.

11. A method for producing a solid-state battery according to any one of claims 1 to 9, comprising: arranging an insulating layer on at least a part of a first end surface of a first electrode layer of either the positive electrode layer or the negative electrode layer, which is exposed on a side surface of a battery element; and arranging an external electrode on at least a part of a second end surface of a second electrode layer of the other of the positive electrode layer and the negative electrode layer, which is exposed on the side surface of the battery element.

12. The method for manufacturing a solid-state battery according to claim 11, wherein the insulating layer is disposed using an inkjet method.

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