Battery

Abstract

A battery 1000 according to the present disclosure comprises: a battery element 1 that includes a first electrode 100, a solid electrolyte layer 300, and a second electrode 200; a first terminal 500a that includes a first electroconductive material; and a second terminal 600a that includes a second electroconductive material. The first terminal 500a is in contact with the first electrode 100. The second terminal 600a covers at least part of the surface of the first terminal 500a, is electrically connected to the first terminal 500a, and directly covers at least part of a corner portion of the battery element 1.

Description

[Technical Field]

[0001] This disclosure relates to batteries. [Background technology]

[0002] Patent Document 1 discloses a surface-mount battery comprising a laminated structure consisting of a first electrode, a solid electrolyte layer, and a second electrode, a protective layer covering the sides of the laminated structure, and an outer casing member housing the laminated structure covered with the protective layer. Patent Document 2 discloses a surface-mountable electronic component in which a metal cap is attached to the end electrode. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2018 / 186449 [Patent Document 2] Japanese Patent Publication No. 2020-87588 [Overview of the project] [Problems that the invention aims to solve]

[0004] The purpose of this disclosure is to improve the reliability of batteries. [Means for solving the problem]

[0005] The battery disclosed herein is A battery element comprising a first electrode, a solid electrolyte layer, and a second electrode, A first terminal containing a first conductive material, A second terminal comprising a second conductive material, The first terminal is in contact with the first electrode, The second terminal covers at least a portion of the surface of the first terminal, is electrically connected to the first terminal, and directly covers at least a portion of the corner of the battery element. [Effects of the Invention]

[0006] The present disclosure can improve the reliability of a battery.

Brief Description of the Drawings

[0007] [Figure 1] FIG. 1 shows a schematic configuration of a battery 1000 according to the first embodiment. [Figure 2] FIG. 2 shows a schematic configuration of a battery 2000 according to the second embodiment. [Figure 3] FIG. 3 shows a schematic configuration of a battery 3000 according to the third embodiment. [Figure 4] FIG. 4 shows a schematic configuration of a battery 4000 according to the fourth embodiment. [Figure 5] FIG. 5 shows a schematic configuration of a battery 5000 according to the fifth embodiment.

Modes for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present disclosure will be specifically described with reference to the drawings.

[0009] Note that all of the embodiments described below show comprehensive or specific examples. Numerical values, shapes, materials, components, arrangement positions of components, connection forms, etc. shown in the following embodiments are merely examples and are not intended to limit the present disclosure.

[0010] In this specification, terms indicating relationships between elements such as parallel, terms indicating shapes of elements such as rectangular parallelepipeds, and numerical ranges are not expressions representing only strict meanings, but are expressions meaning ranges substantially equivalent, for example, including differences of about several percent.

[0011] Each figure is not necessarily drawn precisely. In each figure, substantially the same configurations are denoted by the same reference numerals, and overlapping descriptions are omitted or simplified.

[0012] In this specification and in the drawings, the x, y, and z axes represent the three axes of a three-dimensional Cartesian coordinate system. In each embodiment, the z-axis direction is the thickness direction of the battery. Furthermore, unless otherwise specified in this specification, "thickness direction" refers to the direction perpendicular to the plane on which each layer of the battery element is stacked.

[0013] In this specification, unless otherwise specified, "plan view" means the view of the battery along the stacking direction of the battery elements. In this specification, unless otherwise specified, "thickness" refers to the length of the battery elements and each layer in the stacking direction.

[0014] In this specification, unless otherwise specified, in a battery element, "side surface" means the surface along the stacking direction, and "main surface" means a surface other than the side surface.

[0015] In this specification, "inside" and "outside" as used in terms such as "inside" and "outside" refer to the inside and outside when viewing the battery along the stacking direction.

[0016] In this specification, the terms "upper" and "lower" in the battery configuration do not refer to the upward (vertically upward) and downward (vertically downward) directions in absolute spatial perception, but rather to terms defined by the relative positional relationship based on the stacking order in the stacked configuration. Furthermore, the terms "upper" and "lower" apply not only when two components are placed in close proximity and touching each other, but also when two components are placed spaced apart and another component exists between them.

[0017] (First Embodiment) The battery according to the first embodiment comprises a battery element having a first electrode, a solid electrolyte layer, and a second electrode, a first terminal containing a first conductive material, and a second terminal containing a second conductive material. The first terminal is in contact with the first electrode. The second terminal covers at least a portion of the surface of the first terminal, is electrically connected to the first terminal, and directly covers at least a portion of the end of the battery element. Here, "the second terminal directly covers at least a portion of the end of the battery element" means that the second terminal is in contact with and covers at least a portion of the end of the battery element. Furthermore, the end of the battery element refers to the outer edge portion of the battery element, including the side surface, in the case where the battery element has a laminated structure in which the first electrode, solid electrolyte layer, and second electrode are arranged in this order.

[0018] In the battery according to the first embodiment, the terminal electrically connected to the first electrode (hereinafter referred to as "the terminal of the first electrode") is composed of a multilayer structure including a first terminal and a second terminal. The second terminal is located outside the first terminal and is in contact with both the first terminal and the end of the battery element. As a result, in the battery according to the first embodiment, the terminal of the first electrode has a composite bonding structure composed of the first terminal, the second terminal, and the end of the battery element. This composite bonding structure provides strong adhesion between the battery element, the first terminal, and the second terminal, and as a result, these components are firmly fixed to each other at the end of the battery element. Therefore, volume changes that occur during charge / discharge or thermal cycles are mitigated and deformation of the battery is suppressed, thereby improving the reliability of the battery.

[0019] Furthermore, due to the complex junction structure described above, the battery according to the first embodiment also achieves excellent electrical junction between the terminals of the first electrode and the battery elements. Therefore, the battery according to the first embodiment can adequately handle high-current charging and discharging, i.e., high-rate charging and discharging. Hereinafter, the high-rate charging and discharging characteristics may be referred to as "high-rate characteristics."

[0020] Furthermore, the complex bonding structure described above provides strong adhesion between the components of the battery element and between the battery element and the terminal at the ends of the battery element. This allows the end region of the battery element, which was previously removed by chamfering in conventional configurations, to be retained. Therefore, the battery according to the first embodiment can incorporate active material even in the end region of the battery element, thereby increasing the battery capacity.

[0021] As described above, the battery according to the first embodiment has a composite junction structure composed of a battery element, a first terminal, and a second terminal, which provides reliability such as suppressing deformation that occurs during charge-discharge or thermal cycling, and also enables further improvements in capacity and high-rate characteristics.

[0022] As described in the [Background Technology] section, Patent Document 1 discloses a surface-mount battery in which a protective layer is provided on the side surface of a laminated structure consisting of a first electrode, a solid electrolyte layer, and a second electrode, and these laminated structures and protective layers are housed in an outer casing. These protective layers and outer casings suppress the intrusion of moisture into the battery. On the other hand, the improvement of battery reliability that this disclosure aims to achieve is, preferably, to suppress the decrease in reliability due to deformation stress that occurs during charge-discharge or thermal cycling, while extracting as much battery characteristics as possible, such as high-rate charge-discharge and / or high capacity. For this reason, the battery of this disclosure has a complex bonding structure as described above, in which the terminals of the first electrode of the battery element have a first terminal and a second terminal, and the battery element, the first terminal and the second terminal are composed of the battery element. The battery disclosed in Patent Document 1 does not have a complex bonding structure between the battery element and terminals like the battery of this disclosure. Therefore, the battery disclosed in Patent Document 1 is considered unsuitable for long-term use due to a decrease in reliability caused by volume changes during charge-discharge or thermal cycling, and furthermore, it is considered difficult to improve the capacity and high-rate characteristics that the battery disclosed in this disclosure can achieve. Patent Document 2 discloses a surface-mountable electronic component with a metal cap attached to the end electrode. However, similar to Patent Document 1, the metal cap is attached to the end electrode to prevent moisture ingress. Therefore, the electronic component disclosed in Patent Document 2 is also considered unsuitable for long-term use due to a decrease in reliability caused by volume changes during charge-discharge or thermal cycling, similar to the battery disclosed in Patent Document 1. Furthermore, it is considered difficult to improve the capacity and high-rate characteristics that the battery disclosed in this disclosure can achieve with the electronic component disclosed in Patent Document 2.

[0023] The battery according to the first embodiment may further include a third terminal containing a third conductive material and a fourth terminal containing a fourth conductive material. The third terminal is in contact with the second electrode. The fourth terminal covers at least a portion of the surface of the third terminal, is electrically connected to the third terminal, and directly covers at least a portion of the end of the battery element. That is, the terminal electrically connected to the second electrode (hereinafter referred to as the "second electrode terminal") of the battery according to the first embodiment may have the same configuration as the terminal of the first electrode. Hereinafter, for batteries according to the first to fifth embodiments, an example of a configuration in which the terminal of the second electrode has the same configuration as the terminal of the first electrode, that is, an example of a configuration in which the terminals of both electrodes have the multilayer structure described above, will be described.

[0024] Figure 1 shows the schematic configuration of the battery 1000 according to the first embodiment. Figure 1(a) shows a cross-sectional view of the schematic configuration of the battery 1000 according to the first embodiment as seen from the y-axis direction. Figure 1(b) shows a plan view of the schematic configuration of the battery 1000 as seen from above in the z-axis direction. Figure 1(a) shows a cross-section at the position indicated by line II in Figure 1(b).

[0025] As shown in Figure 1, the battery 1000 includes a battery element 1 comprising a first electrode 100, a second electrode 200, and a solid electrolyte layer 300, a first terminal 500a in contact with the first electrode 100, a second terminal 600a, a third terminal 500b in contact with the second electrode 200, and a fourth terminal 600b. The second terminal 600a covers at least a portion of the surface of the first terminal 500a, is electrically connected to the first terminal 500a, and directly covers at least a portion of the end of the battery element 1. The fourth terminal 600b covers at least a portion of the surface of the third terminal 500b, is electrically connected to the third terminal 500b, and directly covers at least a portion of the end of the battery element 1. The battery element 1 is further provided with, for example, a first insulating member 400a provided at the end including the side surface of the battery element 1 to insulate the first electrode 100 at the end of the battery element 1, and a second insulating member 400b provided to insulate the second electrode 200 at the end of the battery element 1. The second terminal 600a contacts and covers the end of the battery element 1 via the second insulating member 400b. The fourth terminal 600b contacts and covers the end of the battery element 1 via the first insulating member 400a. The battery element 1 has a structure in which the first electrode 100, the solid electrolyte layer 300, and the second electrode 200 are stacked in this order.

[0026] Battery 1000 is, for example, a solid-state battery.

[0027] Hereinafter, the first insulating member 400a and the second insulating member 400b may be collectively referred to simply as the "insulating film." Furthermore, the third terminal 500b differs from the first terminal 500a in that it is in contact with the second electrode 200 rather than the first electrode 100, but its function and effect are substantially the same as those of the first terminal 500a. Therefore, the following explanation of the first terminal 500a also applies to the third terminal 500b. Furthermore, the fourth terminal 600b differs from the second terminal 600a in that it is electrically connected to the second electrode 200 rather than the first electrode 100, but its function and effect are substantially the same as those of the second terminal 600a. Therefore, the following explanation of the second terminal 600a also applies to the fourth terminal 600b.

[0028] In battery 1000, the battery element 1 is composed of one cell.

[0029] An example of the shape of battery element 1 is a rectangular parallelepiped. Another example of the shape of battery element 1 is a cylinder or a polygonal prism.

[0030] The surface of the battery element 1 has a first main surface 2 on which the first electrode 100 is provided, a second main surface 3 facing the first main surface 2 on which the second electrode 200 is provided, and side surfaces. The side surfaces of the battery element 1 are composed of four surfaces, which are two pairs of opposing surfaces, and include the first side surface 4 and the second side surface 5, which are the short-side surfaces of the battery element 1 in a plan view.

[0031] The first main surface 2 and the second main surface 3 are surfaces perpendicular to the thickness direction of the battery element 1. In a plan view, the first main surface 2 has a first electrode exposed region 6 that is not covered by the second insulating member 400b and the first terminal 500a, at a position that overlaps with the second main surface 3, which will be described later. In a plan view, the second main surface 3 has a second electrode exposed region 7 that is not covered by the first insulating member 400a and the third terminal 500b, at a position that overlaps with the first main surface 2, which will be described later.

[0032] The first side surface 4 and the second side surface 5 extend from the outer edge of the first main surface 2 to the outer edge of the second main surface 3 in a direction intersecting the first main surface 2, and are surfaces that connect the first main surface 2 and the second main surface 3. The first side surface 4 and the second side surface 5 are surfaces parallel to the thickness direction of the battery element 1. For example, the first side surface 4 faces the second side surface 5.

[0033] At least a portion of the surface of the battery element 1, for example, at least a portion of at least one surface selected from the group consisting of the first main surface 2, the second main surface 3, the first side surface 4, and the second side surface 5, may be processed to have an uneven, rough surface in order to improve adhesion with the first terminal or the second terminal. For example, at least a portion of the surface of the battery element 1 may be processed to have an uneven, rough surface by polishing with #800 to #1000 grit sandpaper, after which the first terminal, the second terminal, and the insulating film may be applied and formed.

[0034] The surface of the first terminal 500a that contacts the second terminal 600a may be processed to have an uneven, rough surface. In this case, the surface roughness is such that, for example, the maximum height Rz is 10 μm or more and 20 μm or less. This disperses the surface energy of the battery element 1 and reduces the effect of surface tension. As a result, wettability is improved during coating and the accuracy of the shape can be increased. Therefore, the positional accuracy of the first terminal 500a, the second terminal 600a, and the second insulating member 400b is improved, making it less likely for the battery 1000 to short-circuit. In addition, as the surface roughness increases, the surface area of ​​the battery element 1 increases, which improves the adhesion between the surface of the battery element 1 and the first terminal 500a and the second terminal 600a.

[0035] In Figure 1, the first current collector 110, the first active material layer 120, the solid electrolyte layer 300, the second current collector 210, and the second active material layer 220 have the same shape, position, and size in a plan view. However, the first current collector 110, the first active material layer 120, the solid electrolyte layer 300, the second current collector 210, and the second active material layer 220 may differ in shape, position, and size in a plan view. For example, in a plan view, the second active material layer 220 may be larger than the first active material layer 120. The solid electrolyte layer 300 may be larger than both the first active material layer 120 and the second active material layer 220. Furthermore, the solid electrolyte layer 300 may cover the sides of the first active material layer 120 and the second active material layer 220 and be in contact with the first current collector 110 and the second current collector 210.

[0036] As described above, the battery element 1 includes a first electrode 100, a second electrode 200, and a solid electrolyte layer 300. The solid electrolyte layer 300 is located between the first electrode 100 and the second electrode 200.

[0037] The first electrode 100 includes a first current collector 110 and a first active material layer 120. The first current collector may be in contact with the first active material layer 120. The first electrode 100 may include other layers, such as a bonding layer made of a conductive material, between the first current collector 110 and the first active material layer 120.

[0038] The first electrode 100 does not necessarily include the first current collector 110. For example, a terminal for extraction or a substrate supporting a battery 1000 may be electrically connected to the first active material layer 120 and function as a current collector. The first electrode 100 may consist only of the first active material layer 120.

[0039] The second electrode 200 includes a second current collector 210 and a second active material layer 220. The second current collector 210 may be in contact with the second active material layer 220. The second electrode 200 may include other layers, such as a bonding layer made of a conductive material, between the second current collector 210 and the second active material layer 220.

[0040] The second electrode 200 does not necessarily include the second current collector 210. For example, a terminal for extraction or a substrate supporting the battery 1000 may be electrically connected to the second active material layer 220 and function as a current collector. The second electrode 200 may consist only of the second active material layer 220.

[0041] The first electrode 100 may be a positive electrode. In this case, the first current collector 110 is a positive electrode current collector, and the first active material layer 120 is a positive electrode active material layer.

[0042] In this case, the second current collector 210 is a negative electrode current collector, and the second active material layer 220 is a negative electrode active material layer.

[0043] Hereinafter, the first active material layer 120 and the second active material layer 220 may be simply referred to as "active material layers." The first current collector 110 and the second current collector 210 may be simply referred to as "current collectors."

[0044] The current collector may be formed from a conductive material. The material of the current collector is not particularly limited. Examples of current collector materials include stainless steel, nickel, aluminum, iron, titanium, copper, palladium, gold, platinum, or alloys of two or more of these. Examples of current collector shapes include foil, plate, or mesh. The material of the current collector may be appropriately selected considering that it does not melt or decompose under the manufacturing process, operating temperature, and operating pressure, as well as the battery operating potential and conductivity applied to the current collector. The material of the current collector may also be selected according to the required tensile strength and heat resistance. The current collector may be, for example, high-strength electrolytic copper foil, or a clad material formed by laminating dissimilar metal foils.

[0045] The thickness of the current collector may be, for example, 10 μm or more and 100 μm or less. Even if the thickness of the current collector is less than 10 μm, it can be used as long as it satisfies the handling requirements in the manufacturing process, characteristics such as current capacity, and reliability.

[0046] The positive electrode active material layer contains a positive electrode active material. The positive electrode active material is a material in which metal ions such as lithium (Li) ions or magnesium (Mg) ions are inserted into or removed from its crystal structure at a higher potential than the negative electrode, and oxidation or reduction occurs as a result. The type of positive electrode active material can be appropriately selected depending on the type of battery, and known positive electrode active materials can be used.

[0047] The positive electrode active material may be a compound containing lithium and a transition metal element. More specifically, examples of such compounds are oxides containing lithium and a transition metal element or phosphoric acid compounds containing lithium and a transition metal element. An example of an oxide containing lithium and a transition metal element is LiNi x M 1-xLithium nickel composite oxides such as O2 (where M is at least one selected from the group consisting of Co, Al, Mn, V, Cr, Mg, Ca, Ti, Zr, Nb, Mo, and W, and x satisfies 0 < x ≤ 1), layered oxides such as lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), and lithium manganate (LiMn2O4), or lithium manganates having a spinel structure (LiMn2O4, Li2MnO3, LiMnO2). An example of a phosphate compound containing lithium and a transition metal element is lithium iron phosphate (LiFePO4) having an olivine structure. Other examples of the positive electrode active material are sulfides such as sulfur (S) and lithium sulfide (Li2S). When the positive electrode active material is a sulfide, lithium niobate (LiNbO3) or the like may be coated or added to the positive electrode active material particles. As the positive electrode active material, only one of these materials may be used, or two or more of these materials may be combined and used.

[0048] The positive electrode active material layer may contain not only the positive electrode active material but also other additive materials. That is, the positive electrode active material layer may be a binder layer. Examples of the additive materials are solid electrolytes such as inorganic solid electrolytes and sulfide solid electrolytes, conductive aids such as acetylene black, or binders for binding such as polyethylene oxide and polyvinylidene fluoride. By mixing the positive electrode active material and the additive materials at a predetermined ratio, the lithium ion conductivity in the positive electrode active material layer can be improved, and the electron conductivity can also be improved. As the solid electrolyte, for example, the solid electrolyte exemplified as the material constituting the solid electrolyte layer 300 described later can be used.

[0049] The thickness of the positive electrode active material layer may be, for example, 5 μm or more and 300 μm or less.

[0050] The negative electrode active material layer contains a negative electrode active material. The negative electrode active material is a substance in which metal ions such as lithium (Li) ions or magnesium (Mg) ions are inserted into or removed from its crystal structure at a lower potential than that of the positive electrode, and oxidation or reduction occurs as a result. The type of negative electrode active material can be appropriately selected depending on the type of battery, and known negative electrode active materials can be used.

[0051] Examples of negative electrode active materials include carbon materials such as natural graphite, artificial graphite, graphite carbon fiber, and resin-fired carbon, or alloying materials combined with a solid electrolyte. Examples of alloying materials include LiAl, LiZn, Li3Bi, Li3Cd, Li3Sb, Li4Si, Li 4.4 Pb, Li 4.4 Sn, Li 0.17 C, and lithium alloys such as LiC6, lithium titanate (Li4Ti5O 12 Oxides of lithium and transition metal elements, such as zinc oxide (ZnO) and silicon oxide (SiO2). x These are metal oxides such as ). As the negative electrode active material, only one of these materials may be used, or two or more of these materials may be used in combination.

[0052] The negative electrode active material layer may contain not only the negative electrode active material but also other additive materials. That is, the negative electrode active material layer may be a mixture layer. Examples of additive materials include solid electrolytes such as inorganic solid electrolytes and sulfide solid electrolytes, conductive additives such as acetylene black, or binding binders such as polyethylene oxide and polyvinylidene fluoride. By mixing the negative electrode active material and additive materials in a predetermined ratio, the lithium ion conductivity within the negative electrode active material layer can be improved, as can the electronic conductivity. As the solid electrolyte, for example, a solid electrolyte exemplified as a material constituting the solid electrolyte layer 300 described later may be used.

[0053] The thickness of the negative electrode active material layer may be, for example, 5 μm or more and 300 μm or less.

[0054] The solid electrolyte layer 300 is located between the first active material layer 120 and the second active material layer 220. The solid electrolyte layer 300 may be in contact with the first active material layer 120 and the second active material layer 220.

[0055] The solid electrolyte layer 300 contains a solid electrolyte. The solid electrolyte layer 300 contains, for example, a solid electrolyte as a main component. The solid electrolyte may be any known solid electrolyte for a battery that has no electronic conductivity but has ionic conductivity. For the solid electrolyte, for example, a solid electrolyte that conducts metal ions such as lithium ions and magnesium ions can be used. The solid electrolyte may be appropriately selected according to the conduction ion species. Examples of the solid electrolyte are sulfide-based solid electrolytes, oxide-based solid electrolytes, or halogen-based solid electrolytes.

[0056] Examples of sulfide-based solid electrolytes are Li2S-P2S5 systems, Li2S-SiS2 systems, Li2S-B2S3 systems, Li2S-GeS2 systems, Li2S-SiS2-LiI systems, Li2S-SiS2-Li3PO4 systems, Li2S-Ge2S2 systems, Li2S-GeS2-P2S5 systems, or Li2S-GeS2-ZnS systems.

[0057] Examples of oxide-based solid electrolytes are lithium-containing metal oxides such as Li2O-SiO2 and Li2O-SiO2-P2O5, Li x P y O 1-z N z such as lithium-containing metal nitrides, garnet-type solid electrolytes such as Li7La3Zr2O 12 or its element substitution products, lithium phosphate (Li3PO4), or lithium-containing transition metal oxides such as lithium titanate.

[0058] <CROSS_REF_START> Examples of halogen-based solid electrolytes are Li a Me b Y cThis is a compound represented by Z6. Here, the equation a + mb + 3c = 6 and c > 0 are satisfied. Me is at least one element selected from the group consisting of metallic elements other than Li and Y and metalloid elements. Z is at least one element selected from the group consisting of F, Cl, Br, and I. The value of m represents the valence of Me.

[0059] "Metalloid elements" are B, Si, Ge, As, Sb, and Te. "Metallic elements" are all elements in groups 1 through 12 of the periodic table (except hydrogen), and all elements in groups 13 through 16 of the periodic table (except B, Si, Ge, As, Sb, Te, C, N, P, O, S, and Se).

[0060] To increase the ionic conductivity of halogen-based solid electrolytes, Me may be at least one selected from the group consisting of Mg, Ca, Sr, Ba, Zn, Sc, Al, Ga, Bi, Zr, Hf, Ti, Sn, Ta, and Nb.

[0061] Examples of halogenated solid electrolytes are Li3YCl6 or Li3YBr6.

[0062] As a solid electrolyte, only one of these materials may be used, or two or more of these materials may be used in combination.

[0063] The solid electrolyte layer 300 may contain not only a solid electrolyte but also a binding binder such as polyethylene oxide and polyvinylidene fluoride.

[0064] The thickness of the solid electrolyte layer 300 may be, for example, 5 μm or more and 150 μm or less.

[0065] The solid electrolyte layer 300 may be composed of aggregates of solid electrolyte particles. The solid electrolyte layer 300 may be composed of a sintered structure of the solid electrolyte.

[0066] (Insulating film) The battery 1000 may have an insulating film. As shown in Figure 1, the side surface and a portion of the main surface of the battery element 1 may be covered with an insulating film.

[0067] The first insulating member 400a has a first side covering portion 410a located on the first side surface 4 of the battery element 1 and a first main surface covering portion 420a located on the first main surface 2. In Figure 1, the first insulating member 400a does not cover the second main surface 3. The first insulating member 400a may cover a part of the second main surface 3, as long as it does not obstruct contact between the third terminal 500b and the second electrode 200.

[0068] The first insulating member 400a, for example, is in contact with the first main surface 2 and covers the edge of the first main surface 2. The first side covering portion 410a is connected to the first main surface covering portion 420a. In other words, the first insulating member 400a wraps around from the first side surface 4 onto the first main surface 2 and continuously covers the ridge between the first side surface 4 and the first main surface 2.

[0069] The second insulating member 400b has a second side covering portion 410b located on the second side surface 5 of the battery element 1 and a second main surface covering portion 420b located on the second main surface 3. In Figure 1, the second insulating member 400b does not cover the first main surface 2. The second insulating member 400b may cover a part of the first main surface 2, as long as it does not obstruct contact between the first terminal 500a and the first electrode 100.

[0070] The second insulating member 400b, for example, is in contact with the second main surface 3 and covers the edge of the second main surface 3. The second side covering portion 410b is connected to the second main surface covering portion 420b. In other words, the second insulating member 400b wraps around from the second side surface 5 onto the second main surface 3 and continuously covers the ridge between the second side surface 5 and the second main surface 3.

[0071] The first side covering portion 410a and the second side covering portion 410b also cover a portion of the side surface on the long side of the battery element 1 in a plan view (i.e., the xz plane of the battery element 1). The first side covering portion 410a and the second side covering portion 410b may cover all or part of the side surface on the long side of the battery element 1 in a plan view. The first main surface covering portion 420a and the second main surface covering portion 420b may cover a portion of the area along the long side of the main surface of the battery element 1.

[0072] The insulating film material can be any electrical insulator. The insulating film may include, for example, a resin material. The insulating film may contain an insulating resin material as its main component. Examples of resins include epoxy resins, acrylic resins, polyimide resins, or silsesquioxane. For example, a coatable resin material such as a liquid or powder-based thermosetting epoxy resin may be used as the insulating film material. By applying such a coatable resin material in liquid or powder form to the side and main surfaces of the battery element 1 and then thermosetting it, the side and main surfaces of the battery element 1 can be covered with an insulating film, and then bonded and fixed. The insulating film may also have a structure in which multiple insulating layers made of the same or different materials are laminated.

[0073] As described above, the insulating film may also cover part or all of the long side surface of the battery element 1 in a plan view, and may extend continuously from the corners and edges located at the ends of the first side surface 4 and the second side surface 5 of the battery element 1.

[0074] (Terminal 1 and Terminal 3) The first terminal 500a, which includes the first conductive material, is a film-like conductive member that covers a portion of the second insulating member 400b of the battery element 1 from the outside and is electrically connected to the first electrode 100. The second insulating member 400b has a portion of the ridge line connecting the second side surface 5 to the first main surface 2, which is an exposed ridge line portion 700a that is not covered by the first terminal 500a. Therefore, the first terminal 500a and the exposed ridge line portion 700a are covered from the outside by the second terminal 600a, which will be described later, and are fixed in contact with the second terminal 600a. As shown in Figure 1, the exposed ridge line portion 700a may be a corner at the end of the battery element 1. That is, the second terminal 600a may directly cover at least a portion of the corner of the battery element 1. By the battery element 1 being in contact with the second terminal 600a at the corner at its end, stronger adhesion between the battery element 1, the first terminal 500a, and the second terminal 600a is obtained, thereby improving the reliability of the battery. Here, the corner at the end of the battery element 1 refers to the portion where the side surface and the main surface of the battery element 1 come into contact.

[0075] In detail, the first terminal 500a wraps around from the outer surface of the second insulating member 400b to the first electrode 100 located on the first main surface 2, continuously covering at least a portion of the second insulating member 400b and the first electrode 100 on the first main surface 2. However, a portion of the ridge of the second insulating member 400b, such as a corner, becomes the exposed ridge portion 700a and is therefore not covered by the first terminal 500a. The first terminal 500a covers the end of the battery element 1 from the outside. The first terminal 500a also covers the second side surface 5 and the second main surface 3 of the battery element 1 from above the insulating film. Thus, the first terminal 500a may be in contact with the side surface of the battery element 1, as long as it does not come into contact with the second electrode 200.

[0076] The first terminal 500a has a second side covering portion 510a that covers the second side covering portion 410b of the second insulating member 400b, an electrode contact portion 520a that contacts the first main surface 2, and a second main surface covering portion 530a. The second side covering portion 510a, the electrode contact portion 520a, and the second main surface covering portion 530a may be provided so as to be continuous, except for the exposed ridge portion 700a which is the exposed part of the second insulating member 400b.

[0077] The second side covering portion 510a covers the outer surface of the second insulating member 400b. The second side covering portion 510a is in contact with, for example, the outer surface of the second insulating member 400b and is joined to the electrode contact portion 520a and the second main surface covering portion 530a. The second side covering portion 510a of the first terminal 500a covers the second side covering portion 410b.

[0078] In Figure 1, at the first terminal 500a, the second side covering portion 510a covers the second side covering portion 410b of the second insulating member 400b, the electrode contact portion 520a is in contact with a part of the first electrode 100 located on the first main surface 2, in this case a part of the first current collector 110, and the second main surface covering portion 530a covers a part of the second main surface covering portion 420b from the outside.

[0079] In other words, the first terminal 500a wraps around from the outer surface of the second side covering portion 410b of the second insulating member 400b to the outer surface of the second main covering portion 420b, covering a part of the second main covering portion 420b of the second insulating member 400b, and also wraps around from the outer surface of the second side covering portion 410b to the first electrode 100 of the first main surface 2, making contact with the first electrode 100. In a plan view, the inner end of the second main covering portion 530a is located outside the inner end of the second main covering portion 420b. Note that the second main covering portion 530a does not have to completely cover the second main covering portion 420b.

[0080] The electrode contact portion 520a of the first terminal 500a covers at least a part of the first main surface 2 and is joined to the first main surface 2. That is, the electrode contact portion 520a is electrically connected to the first electrode 100. The electrode contact portion 520a is electrically connected to, for example, the first current collector 110. The electrode contact portion 520a is in contact with, for example, the first electrode exposed region 6 on the first main surface 2. As a result, the electrode contact portion 520a is in contact with the first electrode exposed region 6 located near the end of the first main surface 2 on the first terminal 500a side, so the first terminal 500a does not need to wrap around significantly to the inside of the first main surface 2, and the first terminal 500a and the first electrode 100 can be easily electrically connected. In a plan view, the inner end of the second main surface covering portion 530a of the first terminal 500a and the inner end of the electrode contact portion 520a are, for example, in the same position.

[0081] The configuration of the third terminal 500b is substantially the same as that of the first terminal 500a described above. The third terminal 500b, which includes the third conductive material, is a film-like conductive member that covers a portion of the first insulating member 400a of the battery element 1 from the outside and is electrically connected to the second electrode 200. The first insulating member 400a has a portion of the ridge line connecting the first side surface 4 to the second main surface 3, which is an exposed ridge line portion 700b that is not covered by the third terminal 500b. Therefore, the third terminal 500b and the exposed ridge line portion 700b are covered from the outside by the fourth terminal 600b, which will be described later, and are in contact with and fixed to the fourth terminal 600b. As shown in Figure 1, the exposed ridge line portion 700b may be a corner at the end of the battery element 1. By the battery element 1 contacting the fourth terminal 600b at the corner at its end, stronger adhesion between the battery element 1, the third terminal 500b, and the fourth terminal 600b is obtained, thereby improving the reliability of the battery.

[0082] In detail, the third terminal 500b wraps around from the outer surface of the first insulating member 400a to the second electrode 200 located on the second main surface 3, continuously covering at least a portion of the first insulating member 400a and the second electrode 200 on the second main surface 3. However, a portion of the ridge of the first insulating member 400a, such as a corner, becomes the exposed ridge portion 700b and is therefore not covered by the third terminal 500b. The third terminal 500b covers the end of the battery element 1 from the outside. The third terminal 500b also covers the first side surface 4 and the first main surface 2 of the battery element 1 from above the insulating film. Thus, the third terminal 500b may be in contact with the side surface of the battery element 1, as long as it does not come into contact with the first electrode 100.

[0083] The third terminal 500b has a first side covering portion 510b that covers the first side covering portion 410a of the first insulating member 400a, an electrode contact portion 520b that contacts the second main surface 3, and a first main surface covering portion 530b. The first side covering portion 510b, the electrode contact portion 520b, and the first main surface covering portion 530b may be provided so as a whole, except for the exposed ridge portion 700b which is the exposed part of the first insulating member 400a.

[0084] The first side covering portion 510b covers the outer surface of the first insulating member 400a. The first side covering portion 510b is in contact with, for example, the outer surface of the first insulating member 400a and is joined to the electrode contact portion 520b and the first main surface covering portion 530b. The first side covering portion 510b of the third terminal 500b covers the first side covering portion 410a.

[0085] In Figure 1, at the third terminal 500b, the first side covering portion 510b covers the first side covering portion 410a of the first insulating member 400a, the electrode contact portion 520b is in contact with a part of the second electrode 200 located on the second main surface 3, in this case a part of the second current collector 210, and the first main surface covering portion 530b covers a part of the first main surface covering portion 420a from the outside.

[0086] In other words, the third terminal 500b wraps around from the outer surface of the first side covering portion 410a of the first insulating member 400a to the outer surface of the first main covering portion 420a, covering a part of the first main covering portion 420a of the first insulating member 400a, and also wraps around from the outer surface of the first side covering portion 410a to the second electrode 200 of the second main surface 3, making contact with the second electrode 200. In a plan view, the inner end of the first main covering portion 530b is located outside the inner end of the first main covering portion 420a. Note that the first main covering portion 530b does not have to completely cover the first main covering portion 420a.

[0087] The electrode contact portion 520b of the third terminal 500b covers at least a part of the second main surface 3 and is joined to the second main surface 3. That is, the electrode contact portion 520b is electrically connected to the second electrode 200. The electrode contact portion 520b is electrically connected to, for example, the second current collector 210. The electrode contact portion 520b is in contact with, for example, the second electrode exposed region 7 on the second main surface 3. As a result, the electrode contact portion 520b is in contact with the second electrode exposed region 7 located near the end of the second main surface 3 on the third terminal 500b side, so the third terminal 500b does not need to wrap around significantly to the inside of the second main surface 3, and the second terminal 600a and the second electrode 200 can be easily electrically connected. In a plan view, the inner end of the first main surface covering portion 530b of the third terminal 500b and the inner end of the electrode contact portion 520b are, for example, in the same position.

[0088] The thickness of the first terminal 500a and the third terminal 500b is not particularly limited. In order to increase the volumetric energy density of the battery 1000, the thickness of the terminals, in particular the thickness of at least one of the electrode contact portion 520a and the electrode contact portion 520b, may be thinner than the thickness of the current collector. The thickness of the terminals, in particular the thickness of the electrode contact portion 520a and the electrode contact portion 520b, may be, for example, 1 μm or more and 50 μm or less, and 2 μm or more and 40 μm or less, respectively. By having the terminal thickness within the above range, it is possible to suppress the decrease in volumetric energy density while easily mitigating stress caused by the expansion or contraction of the current collector due to temperature changes, thereby stably bringing out the characteristics of the battery 1000.

[0089] (First conductive material and third conductive material) The first conductive material is composed of an electronically conductive material. To handle large currents, such as high-rate charging and discharging, the first conductive material may include a highly conductive metal material mainly containing low-resistance elements such as Ag or copper. For example, the first terminal 500a is formed by applying an electrode paste containing metal particles and heat-treating it (e.g., baking it). Thus, the first conductive material may be a sintered material containing metal. This allows the sintered, low-resistance metal film to suppress heat generation and burnout at the connection point between the current collector, which tends to have high resistance, and the first terminal 500a. Therefore, with this configuration, the battery according to the first embodiment becomes more suitable for high currents, improving the high-rate characteristics and reliability of the battery. Furthermore, high adhesion to the substrate can also be obtained.

[0090] The first conductive material may include a resin material. This can mitigate rapid volume changes due to high-rate charging and discharging. Furthermore, excellent end-face sealing properties can be obtained. Therefore, this configuration enables the realization of a high-performance and highly reliable battery. For example, the first conductive material may include a conductive resin material in which metal particles are densely dispersed to reduce resistance.

[0091] The first terminal 500a, which includes a sintered material and / or a conductive resin material, enables high-rate operation of the battery. Furthermore, the composite bonding structure with the second terminal 600a covering the first terminal 500a, as described later, provides both conductivity and cushioning properties, as well as strong adhesion. As a result, a battery that enables high-rate operation and has high reliability against volume changes that occur during charge-discharge or thermal cycles can be realized.

[0092] When the first terminal 500a is formed by a sintered material, the sintering temperature can be, for example, about half the melting point of the metal. By using particles of a few microns, a sintered conductive film can be obtained. By reducing the particle size, the contact area between particles increases, so the sintering temperature can be further reduced, and it is best to set it considering the heat resistance of the battery element 1.

[0093] To alleviate the stress on the battery element 1 caused by the expansion or contraction of each layer during charging and discharging, the first terminal 500a may be made of a conductive resin material in which the above-mentioned metal particles are densely dispersed. By increasing the contact area between metal particles through the density and refinement of the metal particles, the resistance of a relatively soft conductive resin material can be further reduced. For example, a conductive resin material with a high metal content (e.g., 70% by mass or more) containing fine particles including Ag and / or Cu having a particle size of 0.1 μm to 1 μm may be used as the first conductive material. Also, for example, the first conductive material may have a Young's modulus smaller than that of the metals constituting the first current collector 110 and the second current collector 210. By using a soft material as the first conductive material, expansion and contraction associated with high-rate operation and charge-discharge cycles can be mitigated, thereby improving reliability at easily delaminating connection points (e.g., connections with current collectors).

[0094] To further improve the reliability of the battery 1000, the first conductive material may have a Young's modulus smaller than that of the solid electrolyte layer 300, the first active material layer 120, and the second active material layer 220. This absorbs the deformation stress of the first active material layer 120 and the second active material layer 220, which are the main components of expansion and contraction during charging and discharging, thereby suppressing structural defects and improving the reliability of the battery 1000. To reduce the Young's modulus of the first conductive material, the first conductive material may contain a resin material.

[0095] The relative relationships of Young's moduli can be compared, for example, by examining the displacement characteristics in response to pressure when a probe is pressed in, or by examining the relative sizes of the indentations.

[0096] The first conductive material may include, for example, silver, copper, nickel, zinc, aluminum, palladium, gold, platinum, or alloys of these metals. Alternatively, the first conductive material may be a solid electrolyte containing conductive particles or semiconductor material particles. This allows for adjustment of the coefficient of thermal expansion and hardness relative to the battery element 1, thereby suppressing structural defects caused by stress due to volume changes during charge-discharge or thermal cycling. Therefore, the reliability of low-loss, high-rate batteries can be further improved.

[0097] The first conductive material may contain an oxide. This allows the oxide of the first terminal 500a to bite into the second terminal 600a at the bonding interface with the second terminal 600a, providing an anchoring effect, and as a result, improving the bonding strength between the first terminal 500a and the second terminal 600a. The oxide should preferably be harder than the material bonding to the first terminal 500a (e.g., the current collector, insulating film, and solid electrolyte layer). Examples of oxides with high mechanical strength include alumina (Al2O3) or zirconia (ZrO2). The oxide may be particulate. The size of the oxide particles can be set within the thickness range of the first terminal 500a. The oxide content in the first conductive material is not particularly limited, as long as it is included within the desired conductivity range.

[0098] The first conductive material may be a sintered material containing glass. This fills the pores in the sintered structure with glass components, improving the sealing performance of the first terminal 500a. As a result, the intrusion of moisture into the battery element 1 is suppressed.

[0099] The first conductive material may be a sintered material containing two or more types of glass. That is, the first conductive material may contain glass frit. By baking, the glass frit component melts and adheres to the substrate (for example, the surface irregularities of the current collector), improving the bonding properties of the first terminal 500a. Furthermore, even stronger bonding properties can be obtained by diffusing the glass frit component onto the surface of the current collector, for example, to form a reaction layer such as a diffusion layer or an alloy layer on the surface of the current collector. For example, if the current collector contains Cu, a reaction layer can be formed during baking by adding powders such as Zn, Al, Sn, Sb, and Bi to the first conductive material in a proportion of 0.1 to 10% by mass. Any composition in which an alloy is formed at or below the baking temperature can be used. The glass frit can be, for example, powdered to a few microns and incorporated into metal powder, and the glass component can be melted by heat treatment above its softening point, for example. Furthermore, the molten glass component wets the surface of the metal particles, acting as a sintering aid for the metal particles, which further reduces the sintering temperature and reaction temperature.

[0100] The glass contained in the first conductive material may include both a compacted structure and a molten structure. This allows the compacted structure to absorb stress, and the molten structure to improve sealing properties that prevent the intrusion of moisture, etc., and adhesion to the substrate. Such a glass containing a compacted structure and a molten structure can be realized, for example, by a glass containing two or more glass compositions with different softening points. For example, in a glass composition region where the softening point is higher than the heat treatment temperature, the glass is not completely sintered during heat treatment, resulting in a compacted structure where the glass powders are in contact with each other. On the other hand, in a glass composition region where the softening point is lower than the heat treatment temperature, the structure becomes molten by heat treatment, i.e., a molten structure.

[0101] The glass frit content in the first conductive material may be selected within a range that does not impair the conductivity of the first terminal 500a. For example, it may be included in a range of 0.1 to 10% by mass.

[0102] The softening point of the glass frit can be controlled mainly by the glass composition. For example, various glass compositions may be selected so that the softening point is in the range of 400 to 900°C. Alternatively, multiple glass components with different softening points may be included. This allows the glass structure after firing to have a mixed structure consisting of particulate material (i.e., glass components that did not soften) and molten glass material (after softening). With a glass having such a multi-structure composition, stress generated during thermal cycling or charge / discharge is absorbed by the deformability of the particulate glass powder structure, while adhesion is improved by the molten glass structure. Thus, a first terminal 500a with excellent stress absorption and adhesion reliability can be formed. With such a configuration, a first terminal 500a that enables high-rate charging and discharging and has excellent connection reliability with the battery element 1 can be obtained. The microstructure of the first terminal 500a can be observed using a scanning electron microscope (SEM), optical microscope (e.g., 1k to 5kx magnification), or laser microscope on a polished cross-section obtained using mechanical polishing or an ion polisher. The composition of the microstructure of the first terminal 500a can be quantitatively analyzed in terms of elemental distribution by EPMA (electron beam microanalysis) or EDX (energy-dispersive X-ray spectroscopy).

[0103] The first terminal 500a may be made of a material containing a conductive resin paste, and further containing components of a battery element, such as a solid electrolyte, from the viewpoint of being able to widely adjust its softness (e.g., Young's modulus) in order to suppress peeling of the conductive film. This makes it possible to adjust the coefficient of thermal expansion to approximate that of a battery element and improve resistance to thermal shock.

[0104] The resin included in the first conductive material may be a thermoplastic resin or a thermosetting resin. To facilitate the formation of terminals, the first conductive material may contain a thermosetting resin.

[0105] Examples of thermoplastic resins include polyethylene resins, polypropylene resins, acrylic resins, polystyrene resins, vinyl chloride resins, silicone resins, polyamide resins, polyimide resins, fluorinated hydrocarbon resins, polyether resins, butadiene rubber, isoprene rubber, styrene-butadiene rubber (SBR), styrene-butadiene-styrene copolymer (SBS), styrene-ethylene-butadiene-styrene copolymer (SEBS), ethylene-propylene rubber, butyl rubber, chloroprene rubber, or acrylonitrile-butadiene rubber.

[0106] Examples of thermosetting resins include (i) amino resins such as urea resins, melamine resins, and guanamine resins; (ii) epoxy resins such as bisphenol A type, bisphenol F type, phenol novolac type, and alicyclic type; (iii) oxetane resins; (iv) resol type or novolac type phenolic resins; or (v) silicone-modified organic resins such as silicone epoxy and silicone polyester.

[0107] The first terminal 500a may contain a material having pores or bubbles containing air, etc. Such a structure allows for even wider control of softness (e.g., Young's modulus). As a result, the ability to follow the expansion or contraction of the battery element 1 is improved, and problems such as delamination are further suppressed.

[0108] The first conductive material may include non-flammable and flame-retardant materials such as oxides, ceramics, and solid electrolytes. This improves the heat resistance of the first terminal 500a and also provides the effect of acting as a layer wall to suppress the spread of fire when the battery overheats abnormally.

[0109] The third conductive material included in the third terminal 500b that contacts the second electrode 200 can be the same material as the material described above that can be used as the first conductive material.

[0110] The first terminal 500a and the third terminal 500b may be made of the same material or of different materials. If the first terminal 500a and the third terminal 500b are made of different materials, at least the first terminal 500a may satisfy the above material and physical properties.

[0111] (Second and fourth terminals) The second terminal 600a covers at least a portion of the surface of the first terminal 500a, is electrically connected to the first terminal 500a, and directly covers at least a portion of the end of the battery element 1. That is, the second terminal 600a is in contact with and covers at least a portion of the end of the battery element 1. The second terminal 600a may enclose the first terminal 500a.

[0112] The fourth terminal 600b covers at least a portion of the surface of the third terminal 500b, is electrically connected to the third terminal 500b, and directly covers at least a portion of the end of the battery element 1. That is, the fourth terminal 600b is in contact with and covers at least a portion of the end of the battery element 1. The fourth terminal 600b may enclose the third terminal 500b.

[0113] The second terminal 600a and the fourth terminal 600b are in contact with at least a portion of the end of the battery element 1. With this configuration, a composite bonding structure is formed between the second terminal 600a, the end of the battery element 1, and the first terminal 500a, thereby providing strong adhesion between them. Furthermore, a composite bonding structure is formed between the fourth terminal 600b, the end of the battery element 1, and the third terminal 500b, thereby providing strong adhesion between them. As a result, chamfering is not required at the corners of the battery element 1, allowing the active material to be packed all the way to the end of the battery element 1, thereby increasing the battery capacity.

[0114] (Second conductive material and fourth conductive material) The second terminal 600a, which includes the second conductive material, is made of a conductive material having electronic conductivity.

[0115] The second conductive material may contain a resin material. This further suppresses the intrusion of moisture at the ends of the battery element 1 and improves sealing performance. Furthermore, the elasticity of the second conductive material improves the absorption of stress with respect to the mounting substrate. Stress with respect to the mounting substrate is caused, for example, by volume changes of the battery due to charging and discharging, deflection of the mounting substrate, and impact during mounting.

[0116] The second terminal 600a may be made of a conductive material that is softer than the first terminal 500a. The second terminal 600a covers and fixes the first terminal 500a and the portion not covered by the first terminal 500a (for example, the exposed edge portion 700a of the battery element 1). As a result, the stress on the battery due to charging and discharging, and the stress generated between the battery and the mounting substrate, are mitigated by the buffering properties of the second terminal 600a. As a result, a highly reliable surface-mount battery with excellent rate characteristics can be realized. The stress generated between the battery and the mounting substrate is caused, for example, by thermal expansion and deflection of the mounting substrate, as well as deformation of the battery due to charging and discharging.

[0117] The second conductive material is suitable to contain a highly conductive metal, similar to the first conductive material. The second conductive material may include, for example, at least one of silver, copper, nickel, zinc, aluminum, palladium, gold, platinum, and alloys combining these metals. If both the first and second conductive materials contain conductive resin materials, the metal content of the second conductive material may be lower than that of the first conductive material. This allows for the formation of a softer terminal than that of the first conductive material. Furthermore, the conductivity of the first conductive material can be set higher than that of the second conductive material. In this way, by suppressing the resistance of the first terminal 500a, which is the connection point with the battery element 1 and is the terminal that brings out the battery characteristics, and by making the second terminal 600a, which is a mounting terminal used for connection with the mounting substrate, a soft configuration can be obtained, enabling high-rate charging and discharging and providing a highly reliable battery. The second conductive material may also be a material that contains conductive particles or semiconductor material particles in addition to the metal component in the solid electrolyte. This allows for a wider range of adjustment of the coefficient of thermal expansion and hardness, and suppresses structural defects between the first terminal 500a and the battery element 1 caused by stress such as thermal cycling or thermal shock.

[0118] The second conductive material may be composed of a conductive resin paste containing components of the battery element 1, such as a solid electrolyte, in order to broadly adjust the coefficient of thermal expansion and softness (e.g., Young's modulus). This suppresses delamination and cracking due to thermal cycling or thermal shock.

[0119] The resin included in the second conductive material may be a thermoplastic resin or a thermosetting resin. To facilitate the formation of terminals, the second conductive material may contain a thermosetting resin.

[0120] As thermoplastic resins and thermosetting resins, for example, the same materials as the first conductive material described above can be used.

[0121] The second conductive material may have a different hardness than the first conductive material. This allows for the selection of materials so that the battery characteristics are extracted with low loss by the first terminal 500a, while reliability (e.g., stress absorption, including during sealing and mounting) is provided by the second conductive material at the second terminal 600a. Thus, a surface-mount battery with high performance and high reliability can be realized.

[0122] The second conductive material may be softer than the first conductive material. This allows the second terminal 600a, which contains the second conductive material, to primarily deform and absorb stress during battery use, while the first terminal, made of the first conductive material, is responsible for bringing out the characteristics of the battery element 1. This improves battery performance while enhancing stress absorption and reliability with substrate mounting.

[0123] The second conductive material may have a higher electrical resistance than the first conductive material. This allows the characteristics of the battery element 1 to be brought out with low loss, resulting in a highly reliable battery.

[0124] The second terminal 600a may be made of a material having pores or bubbles containing air, similar to the first terminal 500a. Such a structure allows for further control over a wide range of softness (e.g., Young's modulus), thereby increasing the reliability of the battery 1000 in its mounted state. Thus, the second terminal 600a may contain pores. These pores may include open pores that communicate with the outside. This prevents, for example, plating solution that has entered the pores during soldering from rupturing and scattering into the surroundings due to the heat during soldering, thus preventing short circuits. Open pores can be formed during curing, for example, by including a boiling point component (solvent) below the curing temperature of the thermosetting resin. The second terminal 600a may contain not only metal, but also non-flammable materials such as ceramics and solid electrolytes. When the terminal contains non-flammable or flame-retardant materials, it also has the effect of providing heat resistance to the terminal and acting as a layer wall to suppress the spread of fire when the battery overheats abnormally.

[0125] In the configuration shown in Figure 1, if the first terminal 500a, the second terminal 600a, and the second insulating member 400b all contain resin material, the processing temperatures of the resins can be lower in the order of insulating film, first conductive material, and second conductive material. In the case of thermosetting resins, the processing temperature is, for example, the curing temperature to accelerate the thermal curing of the resin. In the case of thermoplastic resins, the processing temperature is, for example, the phase transition temperature for the flow of the resin (e.g., the glass transition point or melting point). If the insulating film contains a first thermosetting resin, the first conductive material contains a second thermosetting resin, and the second conductive material contains a third thermosetting resin, for example, the curing temperature of the first thermosetting resin is equal to or greater than the curing temperature of the second thermosetting resin, and the curing temperature of the second thermosetting resin is equal to or greater than the curing temperature of the third thermosetting resin. This allows the curing temperature of the first conductive material to be lower than or equal to the curing temperature of the first thermosetting resin contained in the insulating film, and the curing temperature of the second conductive material to be lower than or equal to the curing temperature of the second thermosetting resin contained in the first conductive material. Therefore, it is possible to form terminals while suppressing the deterioration of the properties of the insulating film and the first conductive material, and suppressing the occurrence of peeling and cracking. When the first terminal 500a is formed by baking, and the second terminal and insulating film contain resin material, the processing temperature of the resin may be lower in the order of insulating film and second conductive material. Accordingly, the curing temperature of the thermosetting resin is such that the curing temperature of the thermosetting resin of the insulating film is higher than or equal to the curing temperature of the thermosetting resin of the second conductive material.

[0126] The fourth conductive material included in the fourth terminal 600b can be the same material as the material described above, which can be used as the second conductive material.

[0127] (Second Embodiment) The following describes a battery 2000 according to a second embodiment. Matters described in the above embodiments may be omitted.

[0128] Figure 2 shows the schematic configuration of the battery 2000 according to the second embodiment. Figure 2(a) shows a cross-sectional view of the schematic configuration of the battery 2000 according to the second embodiment as seen from the y-axis direction. Figure 2(b) shows a plan view of the schematic configuration of the battery 2000 according to the second embodiment as seen from the z-axis direction. Figure 2(a) shows a cross-section at the position indicated by the line II-II in Figure 2(b).

[0129] As shown in Figures 2(a) and 2(b), the battery 2000 according to the second embodiment includes a battery element 21 having a configuration in which the entirety of the first electrode 100 and the second electrode 200 are arranged within a solid electrolyte layer 310. The solid electrolyte layer 310 is, for example, an oxide solid electrolyte. Thus, the battery 2000 according to the second embodiment differs from the battery 1000 according to the first embodiment in that the configuration of the battery element 21 is different.

[0130] As the oxide-based solid electrolyte constituting the solid electrolyte layer 310, for example, LAGP-based crystallized glass (Li) has high atmospheric stability. 1.5 Al 0.5 Ge 1.5 (PO4)3), and LLZ(Li7La3Zr2O) with a garnet-type structure 12 Known systems such as the ) system can be used.

[0131] Similar to the battery 1000 according to the first embodiment, the battery 2000 according to the second embodiment includes a first terminal 500a that contacts the first electrode 100, and a second terminal 600a that covers at least a portion of the surface of the first terminal 500a, is electrically connected to the first terminal 500a, and directly covers at least a portion of the end of the battery element 21. In the battery 2000 shown in Figure 2, the first terminal 500a is in contact with the first current collector 110. The second terminal 600a is in contact with and covers the battery element 21 at the corner of the end of the battery element 21 that is not covered by the first terminal 500a.

[0132] Furthermore, similar to the battery 1000 according to the first embodiment, the battery 2000 according to the second embodiment includes a third terminal 500b that contacts the second electrode 200, and a fourth terminal 600b that covers at least a portion of the surface of the third terminal 500b, is electrically connected to the third terminal 500b, and directly covers at least a portion of the end of the battery element 21. In the battery 2000 shown in Figure 2, the third terminal 500b is in contact with the second current collector 210. The fourth terminal 600b is in contact with and covers the battery element 21 at the corner of the end of the battery element 21 that is not covered by the third terminal 500b.

[0133] In the battery 2000 according to the second embodiment, the first terminal 500a, second terminal 600a, third terminal 500b, and fourth terminal 600b can be the same as those described in the first embodiment.

[0134] For example, in the battery 2000 according to the second embodiment, as an example of the first terminal 500a, an electrode paste containing glass frit powder (for example, known materials such as SiO2-Bi2O3-B2O3-ZnO system (softening point, for example, 500 to 550°C)) is applied to Cu powder particles of a highly conductive metal material (for example, Cu particles with a particle size of 0.3 to 1 μm) by end-face coating, and then baked in a nitrogen atmosphere where Cu does not oxidize at 550 to 600°C, above the softening point of the glass frit. The glass component diffuses and reacts with the underlying oxide solid electrolyte during baking to form a diffusion layer, and in addition to the anchoring effect, the first conductive material and the oxide solid electrolyte are strongly bonded. For example, the thickness of the first terminal 500a is 1 to 10 μm. By making the thickness 1 μm or more, the baked metal film is less likely to shrink during sintering and form islands, making it easier to obtain a continuous conductive film. Furthermore, by keeping the thickness 10 μm or less, the metal film thickness does not become excessive, making it less likely to peel off from the battery element 21 due to expansion and contraction during charging, discharging, or thermal cycling. The same configuration as the first terminal 500a can also be applied to the third terminal 500b.

[0135] For example, in the battery 2000 according to the second embodiment, an example of the second conductive material included in the second terminal 600a is a thermosetting epoxy-based conductive resin material containing Ag particles (for example, Ag particles with a particle size of 0.3 to 1 μm). For example, the second terminal 600a may be formed by coating this conductive resin material and curing it in nitrogen at approximately 200°C. Such a second terminal 600a is softer than the first terminal 500a formed using an electrode paste containing Cu powder particles and glass frit powder as described above. This allows for expansion and contraction during charging and discharging, as well as stress with the mounting substrate, while still bringing out the characteristics of the battery. For example, the thickness of the second terminal 600a is 1 to 10 μm. The thickness of the second terminal 600a may be set appropriately from the viewpoint of stress relaxation. If it is excessively thick, it will lead to a decrease in volumetric energy density, so it is best to form it with an appropriate thickness. The second terminal 600a may also be formed by coating a thermosetting conductive resin and curing it by heat treatment in nitrogen. By performing heat treatment in a non-oxidizing atmosphere in this manner, surface oxidation of the metal particles contained in the second conductive material can be suppressed, thereby reducing connection resistance during mounting and preventing deterioration of solder wettability. The same configuration as that used for the second terminal 600a can also be applied to the fourth terminal 600b.

[0136] In the battery 2000 according to the second embodiment, it is possible to form the active material layer even in the end regions of the rectangular parallelepiped, which would normally be chamfered and removed in the case of a chip component, thereby increasing the capacity. Furthermore, since the ends of the battery 2000 are covered with, for example, a relatively soft second terminal 600a, the problem of chipping is reduced. In addition, since the second terminal 600a is bonded to two different material surfaces, the first terminal 500a and the solid electrolyte layer 310 of the battery element 21, a composite bonding structure is obtained, similar to the battery 1000 according to the first embodiment, resulting in strong adhesion.

[0137] As described above, the battery 2000 according to the second embodiment also provides the same effects as the battery 1000 according to the first embodiment.

[0138] (Third embodiment) The following describes a battery 3000 according to a third embodiment. Matters described in the above embodiments may be omitted.

[0139] Figure 3 shows the schematic configuration of the battery 3000 according to the third embodiment. Figure 3(a) shows a cross-sectional view of the schematic configuration of the battery 3000 according to the third embodiment as seen from the y-axis direction. Figure 3(b) shows a plan view of the schematic configuration of the battery 3000 according to the third embodiment as seen from the z-axis direction. Figure 3(a) shows a cross-section at the position indicated by the line III-III in Figure 3(b).

[0140] As shown in Figures 3(a) and 3(b), the battery 3000 according to the third embodiment has a solder plating film 800 formed on the surface of the second terminal 600a. That is, the battery 3000 according to the third embodiment has a configuration that further includes solder material compared to the battery 2000. In the battery 3000 according to the third embodiment, a solder plating film 800 is also formed on the surface of the fourth terminal 600b. Except for the presence of the solder plating film 800, the battery 3000 according to the third embodiment has the same configuration as the battery 2000 according to the second embodiment. Examples of solder plating include Sn plating on a Ni base.

[0141] Thus, the battery 3000 is equipped with solder material in contact with the second terminal 600a and the fourth terminal 600b. This allows it to be soldered onto a mounting board as a standard surface-mount component, for example, by a commonly used process such as reflow soldering. This configuration makes it easy to surface-mount a high-performance and highly reliable battery, and since it can be mounted on a board in the same way as other common surface-mount components such as multilayer ceramic capacitors (MLCCs), it has great industrial value.

[0142] Solder plating can be formed by electrolytic plating, such as barrel plating, which is commonly used for chip components. For example, the underlying Ni thickness is 0.5 to 5 μm and the Sn thickness is 0.5 to 5 μm. The Ni film only needs to be formed without defects (e.g., cracks or voids), but if it is excessively thick, the film stress during deposition can act strongly and cause cracks in the substrate. The Sn thickness is not particularly limited, but if it is excessively thick, cracks are more likely to occur in the Ni film during thermal cycling, which can negatively affect solder wettability and lead to a decrease in volumetric energy density. For these reasons, the plating thickness should be set appropriately. The composition of the solder plating film is not limited to Sn, and any known solder material can be used, such as lead-free or lead-based solder, as long as it is suitable for substrate mounting applications and has good solder wettability.

[0143] (Fourth Embodiment) The following describes a battery 4000 according to a fourth embodiment. Matters described in the above embodiments may be omitted.

[0144] Figure 4 shows the schematic configuration of the battery 4000 according to the fourth embodiment. Figure 4(a) shows a cross-sectional view of the schematic configuration of the battery 4000 according to the fourth embodiment as seen from the y-axis direction. Figure 4(b) shows a plan view of the schematic configuration of the battery 4000 according to the fourth embodiment as seen from below in the z-axis direction. Figure 4(a) shows a cross-section at the position indicated by the line IV-IV in Figure 4(b).

[0145] As shown in Figures 4(a) and 4(b), the battery 4000 according to the fourth embodiment differs from the battery 1000 in that it includes a second insulating member 900, lead terminals 910a and 910b. The lead terminals 910a and 910b are soldered to the second terminal 600a and the fourth terminal 600b, respectively. The second insulating member 900 contains the battery element 1, the first terminal 500a, the second terminal 600a, the third terminal 500b, and the fourth terminal 600b. At least a portion of the lead terminals 910a and 910b are located outside the second insulating member 900 as mounting terminals.

[0146] With the above configuration, a small, highly reliable surface-mount battery can be realized.

[0147] The second insulating member 900 can be made of an insulating resin similar to that of the aforementioned insulating member, such as a thermosetting epoxy resin, and may be made of a material commonly used in mold applications that can block air and moisture, such as in devices. The external terminal portion of the lead terminal (i.e., the portion exposed from the second insulating member 900) may be partially solder-plated (for example, Sn-based solder plating with a thickness of 1 μm) on a SUS plate with a thickness of 0.3 mm. After soldering the lead terminals 910a and 910b to the second terminal 600a and fourth terminal 600b, respectively, the battery 4000 is obtained by placing it in a thermosetting epoxy resin liquid poured into a mold and heat-curing it at, for example, 200 to 240°C. With this configuration, surface-mount compatible forms such as reflow are also possible.

[0148] The lead terminals 910a and 910b may be made of, for example, stainless steel (SUS).

[0149] In this way, by housing the battery 4000 within the molded resin using the second insulating member 900, the lead terminals 910a and 910b can also absorb stress caused by the bending of the substrate and volume changes due to charge / discharge or thermal cycling between the substrate and the mounting substrate, further improving stress absorption and enhancing impact resistance and adhesion resistance. In addition, the molded insulating resin acts as a protective layer for the battery 4000, improving environmental resistance (e.g., moisture resistance). Furthermore, if the mounting portion of the lead terminals is treated with, for example, solder plating, solder mounting such as reflow soldering becomes possible.

[0150] (Fifth embodiment) The following describes a battery 5000 according to a fifth embodiment. Matters described in the above embodiments may be omitted.

[0151] Figure 5 shows the schematic configuration of the battery 5000 according to the fifth embodiment. Figure 5(a) shows a cross-sectional view of the schematic configuration of the battery 5000 according to the fifth embodiment as seen from the y-axis direction. Figure 5(b) shows a plan view of the schematic configuration of the battery 5000 according to the fifth embodiment as seen from below in the z-axis direction. Figure 5(a) shows a cross-section at the position indicated by the VV line in Figure 5(b).

[0152] As shown in Figures 5(a) and 5(b), the battery 5000 according to the fifth embodiment has a configuration in which two batteries 3000 are stacked. That is, the battery 5000 differs from the battery 3000 according to the third embodiment in that it includes multiple single cells. In the battery 3000, as described in the third embodiment, as shown in Figure 3, a solder plating film 800 is formed on the surface of the second terminal 600a and the fourth terminal 600b, and the lead terminals 920 are bonded to this solder plating film 800.

[0153] The lead terminal 920 is formed, for example, from a plate-shaped conductive member, and a plate-shaped member made of SUS with a thickness of 0.3 mm may be used.

[0154] The multiple single cells, known as Battery 3000, contained within Battery 5000 may be connected in series with each other.

[0155] As described above, the lead terminal 920 is, for example, a plate-shaped member and is joined to the solder plating film 800 on the surface of the second and fourth terminals of the battery 3000, respectively, with, for example, Sn-based solder. The lower part of the lead terminal 920 is a mounting terminal 921 for connection to the mounting substrate, formed, for example, by bending the plate-shaped member constituting the lead terminal 920 in a direction substantially parallel to the main surface of the battery 3000. Therefore, during mounting, the connection to the mounting substrate can be performed via the plate-shaped member constituting the lead terminal 920. It is preferable to use solder with a higher melting point than the solder used during mounting when joining the lead terminal 920 to the battery 3000. This ensures reliable mounting without the second terminal of the battery 3000 and the lead terminal 920 becoming detached during mounting.

[0156] A gap may be provided between the lower part of the battery 5000 and the mounting substrate. This allows the battery 5000 to avoid direct contact with the mounting substrate even if the mounting substrate experiences significant deflection, and the deflection can be absorbed by the deformation of the lead terminals 920. This configuration further improves the deflection resistance of the battery 5000 and enhances the reliability of the high-performance battery.

[0157] [Battery manufacturing method] The following describes an example of a method for manufacturing the battery according to this disclosure. As an example, a method for manufacturing battery 1000 according to the first embodiment will be described.

[0158] In the following explanation, the first electrode 100 is the positive electrode, and the second electrode 200 is the negative electrode.

[0159] First, pastes are prepared for printing and forming the first active material layer 120 (hereinafter referred to as the positive electrode active material layer) and the second active material layer 220 (hereinafter referred to as the negative electrode active material layer). As the solid electrolyte raw material used in the respective mixtures of the positive electrode active material layer and the negative electrode active material layer, for example, a glass powder of Li2S-P2S5 system sulfide with an average particle size of approximately 10 μm and mainly composed of triclinic crystals is prepared. This glass powder is, for example, 2 × 10 -3 From 3 x 10 -3 It has high ionic conductivity of approximately S / cm. As a positive electrode active material, for example, a layered Li·Ni·Co·Al composite oxide (LiNi) has an average particle size of about 5 μm. 0.8 Co 0.15 Al 0.05 A powder of O2 is used. A paste for the positive electrode active material layer is prepared by dispersing a mixture containing the above-mentioned positive electrode active material and the above-mentioned glass powder in an organic solvent or the like. As the negative electrode active material, for example, powder of natural graphite with an average particle size of about 10 μm is used. A paste for the negative electrode active material layer is prepared by dispersing a mixture containing the above-mentioned negative electrode active material and the above-mentioned glass powder in an organic solvent or the like.

[0160] Next, copper foil with a thickness of approximately 15 μm is prepared as the material to be used as the first current collector 110 (hereinafter referred to as the positive electrode current collector) and the second current collector 210 (hereinafter referred to as the negative electrode current collector). For example, by screen printing, paste for the positive electrode active material layer and paste for the negative electrode active material layer are printed on one surface of each copper foil in a predetermined shape and with a thickness of approximately 50 μm or more and 100 μm or less. The paste for the positive electrode active material layer and paste for the negative electrode active material layer are dried at a temperature of 80°C or higher and 130°C or lower to a thickness of 30 μm or more and 60 μm or less. In this way, a positive electrode active material layer is formed on the positive electrode current collector and a negative electrode active material layer is formed on the negative electrode current collector.

[0161] Next, a paste for the solid electrolyte layer is prepared by dispersing the mixture containing the aforementioned glass powder in an organic solvent or the like. The paste for the solid electrolyte layer is printed onto the positive electrode and the negative electrode using a metal mask to a thickness of, for example, about 100 μm. After that, the positive electrode and the negative electrode with the printed solid electrolyte layer paste are dried at a temperature of 80°C or higher and 130°C or lower.

[0162] Next, the solid electrolyte printed on the positive electrode and the solid electrolyte printed on the negative electrode are stacked so that they are in contact with and facing each other.

[0163] Next, the laminated body is pressed in a pressure mold. Specifically, between the laminate and the pressure mold plate, that is, on the upper surface of the current collector of the laminate, for example, a material with a thickness of 70 μm and an elastic modulus of 5 × 10⁻¹⁰ is applied. 6 An elastic sheet with a pressure of approximately Pa is inserted. In this configuration, pressure is applied to the laminate through the elastic sheet. Subsequently, the laminate is pressurized for 90 seconds while the pressurizing mold is heated to 50°C at a pressure of 300 MPa. This yields the battery element 1.

[0164] Next, a thermosetting epoxy resin is screen-printed onto the end faces (both short sides) of the battery prepared as described above to a thickness of approximately 20 to 40 μm. A portion that wraps around to the long side is also formed at the same time. After that, it is cured at approximately 120 to 150°C for 1 to 3 hours. This is repeated twice to laminate and form an insulating film of approximately 30 to 60 μm (i.e., the first side covering portion 410a and the second side covering portion 410b of the insulating member).

[0165] Then, the wrap-around portions to the main surface (first main surface coating portion 420a and second main surface coating portion 420b) are coated to a thickness of approximately 10 μm by screen printing and cured at approximately 120 to 150°C for 1 to 3 hours to form the structure. Next, a thermosetting conductive paste containing Ag particles with an average particle diameter of 0.5 μm is screen printed to a thickness of approximately 30 μm onto the first main surface 2 and second main surface 3 of the battery element 1 prepared as described above, forming a pattern to create the electrode contact portion 520a of the first terminal 500a and the electrode contact portion 520b of the third terminal 500b. Furthermore, the thermosetting conductive paste containing Ag particles is screen printed to a thickness of approximately 30 μm onto the first insulating member 400a of the first side surface 4 and the second insulating member 400b of the second side surface 5 of the battery element 1, excluding the exposed ridge portions 700a and 700b. The first terminal 500a and the third terminal 500b are formed by curing at a temperature below the curing temperature of the insulating material, for example, at 120 to 130°C for 0.5 to 3 hours. At this time, the first terminal 500a and the third terminal 500b may be laminated together as needed to achieve the desired thickness. Next, a thermosetting conductive paste containing Ag particles with a lower Ag content than the one used to form the first terminal 500a and the third terminal 500b is applied as a second conductive material to cover the outside of the first terminal 500a and the third terminal 500b, and the second terminal 600a and the fourth terminal 600b are formed by curing at 100 to 120°C for 0.5 to 3 hours.

[0166] In this way, battery 1000 is obtained. After this, the parts other than the second terminal 600a and the fourth terminal 600b may be treated with a resist, and Sn-based solder plating (for example, solder plating with a thickness of 3 to 7 μm) on a Ni substrate (for example, a Ni substrate with a thickness of 1 to 2 μm) may be applied by electroplating.

[0167] The method and sequence for forming the battery 1000 are not limited to the examples described above.

[0168] The above-described manufacturing method shows an example in which the paste for the positive electrode active material layer, the paste for the negative electrode active material layer, the paste for the solid electrolyte layer, and the conductive paste are applied by printing, but is not limited to this. Examples of printing methods include the doctor blade method, calendering method, spin coating method, dip coating method, inkjet method, offset method, die coating method, and spray method.

[0169] In the manufacturing method described above, a thermosetting conductive paste containing Ag metal particles was given as an example of the conductive paste, but it is not limited to this. Furthermore, the resin used in the thermosetting conductive paste can be any resin that functions as a binding binder, and a suitable resin can be selected depending on the manufacturing process adopted, considering factors such as printability and coatability. Resins used in thermosetting conductive pastes include, for example, thermosetting resins. Examples of thermosetting resins include (i) amino resins such as urea resin, melamine resin, and guanamine resin; (ii) epoxy resins such as bisphenol A type, bisphenol F type, phenol novolac type, and alicyclic type; (iii) oxetane resin; (iv) phenol resins such as resol type and novolac type; and (v) silicone-modified organic resins such as silicone epoxy and silicone polyester. Only one of these materials may be used as the resin, or two or more of these materials may be used in combination. [Industrial applicability]

[0170] The battery relating to this disclosure can be used, for example, as a secondary battery such as a surface-mount all-solid-state battery used in various electronic devices or automobiles. [Explanation of Symbols]

[0171] 100 1st electrode 110 First current collector 120 First active material layer 200 2nd electrode 210 Second current collector 220 Second active material layer 300, 310 solid electrolyte layer 400a First insulating member 400b Second insulating member 500a Terminal 1 500b 3rd terminal 600a Second terminal 600b 4th terminal 800 Solder Plating Film 900 Second insulating member 910a, 910b lead terminals 1000, 2000, 300, 4000, 5000 batteries

Claims

1. A battery element comprising a first electrode, a solid electrolyte layer, and a second electrode, A first terminal containing a first conductive material, A second terminal containing a second conductive material, Equipped with, The first terminal is in contact with the first electrode, The second terminal covers at least a portion of the surface of the first terminal, is electrically connected to the first terminal, directly covers at least a portion of the corner of the battery element, and encloses the first terminal. battery.

2. The first conductive material is a sintered material containing a metal. The battery according to claim 1.

3. The first conductive material is a sintered material containing glass. The battery according to claim 1.

4. The first conductive material is a sintered material containing two or more types of glass. The battery according to claim 3.

5. The glass comprises a compacted structure and a molten structure. The battery according to claim 3 or 4.

6. The first conductive material includes a resin material. The battery according to any one of claims 1 to 5.

7. The first conductive material includes an oxide, The battery according to any one of claims 1 to 6.

8. The second conductive material includes a resin material. The battery according to any one of claims 1 to 7.

9. The second conductive material is a material with a different hardness from the first conductive material. The battery according to any one of claims 1 to 8.

10. The second conductive material is softer than the first conductive material. The battery according to any one of claims 1 to 9.

11. The second conductive material has a higher electrical resistance than the first conductive material. The battery according to any one of claims 1 to 10.

12. The second conductive material includes pores, The battery according to any one of claims 1 to 11.

13. The pores include open pores. The battery according to claim 12.

14. We also have soldering materials, The solder material is in contact with the second terminal. The battery according to any one of claims 1 to 13.

15. Further equipped with insulating material, The insulating member encloses the battery element, the first terminal, and the second terminal. The battery according to any one of claims 1 to 14.

16. A third terminal containing a third conductive material, A fourth terminal containing a fourth conductive material, Furthermore, The third terminal is in contact with the second electrode, The fourth terminal covers at least a portion of the surface of the third terminal, is electrically connected to the third terminal, and directly covers at least a portion of the end of the battery element. The battery according to any one of claims 1 to 15.

Images