Battery and battery manufacturing method

Abstract

Provided is a battery including: a power generation element containing at least one solid-state battery cell that contains a positive electrode, a solid-state electrolyte layer, and a negative electrode, which are laminated; a first pressurizing member that comes into contact with a first principal surface of the power generation element; a second pressurizing member that comes into contact with a second principal surface of the power generation element, the second principal surface being on the opposite side from the first principal surface; and an insulation member, wherein the first pressurizing member has first cavities, the second pressurizing member has second cavities, and the insulation member includes side-surface sections that cover side surfaces of the power generation element and extending sections that respectively extend from the side-surface sections into the interiors of the first cavities and the second cavities.

Description

[Technical Field]

[0001] The present disclosure relates to batteries and methods for manufacturing batteries. [Background technology]

[0002] BACKGROUND ART Conventionally, laminate batteries in which a plurality of power generating elements are enclosed in a laminate film have been known as lightweight batteries that have high energy density and power density (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-133175 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a battery that has good charge / discharge characteristics and high energy density. [Means for solving the problem]

[0005] A battery according to one embodiment of the present disclosure includes: a power generating element including at least one solid-state battery cell including a stacked positive electrode, a solid electrolyte layer, and a negative electrode; a first pressure member in contact with a first main surface of the power generating element; a second pressure member in contact with a second main surface of the power generating element opposite the first main surface; and an insulating member, wherein the first pressure member has a first gap, the second pressure member has a second gap, and the insulating member includes a side portion covering a side surface of the power generating element and an extension portion extending from the side portion into each of the first gap and the second gap.

[0006] A method for manufacturing a battery according to one embodiment of the present disclosure includes the steps of: arranging a first pressure member having a first void in contact with a first main surface of a power generating element including at least one solid-state battery cell including a stacked cathode, a solid electrolyte layer, and an anode; and arranging a second pressure member having a second void in contact with a second main surface of the power generating element; sandwiching the power generating element between the first pressure member and the second pressure member and applying pressure; arranging, while applying pressure, a flowable insulating material so that the insulating material covers a side surface of the power generating element and is contained within each of the first void and the second void; and hardening the insulating material while applying pressure. [Effects of the Invention]

[0007] According to the present disclosure, a battery having good charge / discharge characteristics and high energy density can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a top view and a cross-sectional view showing a schematic configuration of a battery according to a first embodiment. [Figure 2] FIG. 2 is a top view and a cross-sectional view showing a schematic configuration of a battery according to the second embodiment. [Figure 3] FIG. 3 is a top view and a cross-sectional view showing a schematic configuration of a battery according to the third embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing a schematic configuration of a battery according to the fourth embodiment. [Figure 5] FIG. 5 is a cross-sectional view showing a schematic configuration of a battery according to the fifth embodiment. [Figure 6A] FIG. 6A is a cross-sectional view showing one step of the method for manufacturing a battery according to the embodiment. [Figure 6B] FIG. 6B is a cross-sectional view showing one step of the method for manufacturing the battery according to the embodiment. [Figure 6C] FIG. 6C is a cross-sectional view showing a step of the method for manufacturing the battery according to the embodiment. [Figure 6D] FIG. 6D is a cross-sectional view showing a step of the method for manufacturing the battery according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (Findings that formed the basis of this disclosure) First, the inventors' viewpoint will be explained below.

[0010] In all-solid-state batteries, constraining the battery ensures good contact between the active material particles and the solid electrolyte particles, and between the solid electrolyte particles themselves. This reduces grain boundary resistance, improving the charge / discharge characteristics of the battery. Thus, constraining is essential for improving battery performance. However, constraining requires a jig, which increases the volumetric ratio of components other than the elements that contribute to power generation to the entire battery. This is disadvantageous in terms of battery performance per volume. In other words, it is difficult to increase the energy density of the battery while achieving good charge / discharge characteristics.

[0011] Therefore, a battery according to one aspect of the present disclosure includes a power generating element including at least one solid-state battery cell including a stacked positive electrode, a solid electrolyte layer, and a negative electrode, a first pressure member in contact with a first main surface of the power generating element, a second pressure member in contact with a second main surface of the power generating element opposite to the first main surface, and an insulating member. The first pressure member has a first gap. The second pressure member has a second gap. The insulating member includes a side portion covering a side surface of the power generating element and an extension portion extending from the side portion into each of the first gap and the second gap.

[0012] As a result, the extending portion of the insulating member can restrain the first and second pressure members in the direction of approaching each other, thereby restraining and maintaining the power generating element sandwiched between the first and second pressure members. This improves the charge / discharge characteristics of the battery. Furthermore, since no jig is required to apply external restraining pressure to the battery, the energy density of the battery can be increased. Thus, according to this aspect, a battery with good charge / discharge characteristics and high energy density can be realized.

[0013] Furthermore, for example, the first gap may be continuous from one end to the other end of the first pressure member in a direction parallel to the first main surface.

[0014] This allows the extending portion located inside the first gap to apply a large pressure to the first pressure member, thereby further improving the charge / discharge characteristics of the battery.

[0015] Furthermore, for example, the first gap may be a through-hole that passes through the first pressure member in a direction parallel to the first main surface.

[0016] This allows the extending portion located inside the first gap to apply a large pressure to the first pressure member, thereby further improving the charge / discharge characteristics of the battery.

[0017] Furthermore, for example, the first pressure member may have a plurality of the first voids, and the plurality of first voids may be arranged in a stripe pattern in a plan view.

[0018] This allows the extending portion located inside the first gap to apply a large and uniform pressure to the first pressure member within its plane, thereby further improving the charge / discharge characteristics of the battery.

[0019] Furthermore, for example, the first pressure member may have a plurality of the first voids, and the plurality of first voids may be arranged in a lattice pattern in a plan view.

[0020] This allows the extending portion located inside the first gap to apply a large and uniform pressure to the first pressure member within its plane, thereby further improving the charge / discharge characteristics of the battery.

[0021] Furthermore, for example, the insulating member may include a resin material having insulating properties.

[0022] This allows the extension portion and the side surface portion to be integrally formed from a resin material. Since the extension portion and the side surface portion are firmly connected to each other, a strong restraining pressure on the power generating element can be maintained.

[0023] Furthermore, for example, the first pressure member and the second pressure member may each be harder than the insulating member.

[0024] This allows the power generating element to be tightly restrained by the first and second pressure members, thereby improving the charge / discharge characteristics of the battery.

[0025] Furthermore, for example, the power generating element may include a plurality of the solid-state battery cells, and the plurality of the solid-state battery cells may be stacked in a direction perpendicular to the first main surface.

[0026] When an all-solid-state battery including multiple stacked solid-state battery cells is constrained, the thickness of the all-solid-state battery increases compared to when a single solid-state battery cell is included. This makes it more likely that pressure loss will occur inside the solid-state battery cell group. To avoid performance degradation due to pressure loss, the battery needs to be constrained with a greater constraining pressure than when a single solid-state battery cell is included. According to the battery of this aspect, the extending portion of the insulating member can apply a greater constraining pressure to the power-generating element. Therefore, according to this aspect, a battery with good charge / discharge characteristics and high energy density can be realized.

[0027] Furthermore, for example, the plurality of solid-state battery cells may be electrically connected in series, and the first pressure member and the second pressure member may be electrically conductive.

[0028] This allows the first and second pressure members to be used as electrode terminals of the battery, eliminating the need to provide separate terminals for the battery, thereby increasing the energy density.

[0029] Furthermore, a method for manufacturing a battery according to one embodiment of the present disclosure includes the steps of: arranging a first pressure member having a first void in contact with a first main surface of a power generation element including at least one solid-state battery cell including a stacked cathode, a solid electrolyte layer, and an anode; and arranging a second pressure member having a second void in contact with a second main surface of the power generation element; sandwiching the power generation element between the first pressure member and the second pressure member and applying pressure; arranging, while applying pressure, a flowable insulating material so that the material covers a side surface of the power generation element and is contained within each of the first void and the second void; and hardening the insulating material while applying pressure.

[0030] As a result, even after the pressure is released, the cured resin material present in the first and second voids maintains the confining pressure on the power generating element, allowing the production of a battery with good charge / discharge characteristics and high energy density.

[0031] Hereinafter, the embodiments will be specifically described with reference to the drawings.

[0032] The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components not described in the independent claims are described as optional components.

[0033] Furthermore, each figure is a schematic diagram and is not necessarily an exact illustration. Therefore, for example, the scales of the figures do not necessarily match. Furthermore, in each figure, substantially the same components are given the same reference numerals, and redundant explanations are omitted or simplified.

[0034] Furthermore, in this specification, terms indicating the relationship between elements, such as parallel or perpendicular, terms indicating the shape of elements, such as rectangular or circular, and numerical ranges are not expressions that only express a strict meaning, but are expressions that also include a substantially equivalent range, for example, a difference of about a few percent.

[0035] In this specification and drawings, the x-axis, y-axis, and z-axis 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. The "thickness direction" is the direction perpendicular to the surface on which each layer is stacked. In addition, in this specification, "planar view" means the case where the battery is viewed along the stacking direction of the battery.

[0036] In addition, in this specification, the terms "inside" and "outside" refer to the direction toward the center of the battery, and the direction away from the center of the battery, unless otherwise specified.

[0037] Furthermore, in this specification, the terms "upper" and "lower" in the battery configuration do not refer to the upper direction (vertically upper) and lower direction (vertically lower) in absolute spatial recognition, but are used as terms defined by a relative positional relationship based on the stacking order in the stacking configuration. Furthermore, the terms "upper" and "lower" are applied not only to a case where two components are arranged with a gap between them and another component exists between the two components, but also to a case where two components are arranged closely together and the two components are in contact with each other.

[0038] (Embodiment 1) [1-1. Battery Overview] First, an overview of the battery according to the first embodiment will be described with reference to FIG.

[0039] FIG. 1 is a top view and a cross-sectional view showing a schematic configuration of a battery 1 according to embodiment 1. FIG. 1(a) is a plan view of the battery 1 as seen from the positive side of the z-axis. FIG. 1(b) is a cross-sectional view taken along the line Ib-Ib in FIG. 1(a). FIG. 1(c) is a cross-sectional view taken along the line Ic-Ic in FIG. 1(a). In FIG. 1(a), components that are the same as those shown in (b) and (c) are shaded in the same way to make it easier to understand the correspondence between FIG. 1(a) and (b) and (c). This also applies to FIG. 2, which will be described later.

[0040] 1, the battery 1 includes a power generating element 10, pressure members 20 and 30, and an insulating member 40. The battery 1 is an all-solid-state battery.

[0041] 1(b), in this embodiment, the pressing members 20 and 30 are provided with gaps 21 and 31, respectively. The gaps 21 and 31 are provided with extensions 42 and 43, which are part of the insulating member 40, respectively. The extensions 42 and 43 restrain the pressing members 20 and 30 in directions approaching each other, thereby restraining the power-generating element 10. In other words, the insulating member 40 maintains a restraining pressure on the power-generating element 10, so that the battery 1 can have good charge / discharge characteristics even without a restraining jig.

[0042] The components that make up the battery 1 will be described in detail below.

[0043] [1-2. Power generation elements] First, the specific configuration of the power generating element 10 will be described.

[0044] The power generating element 10 includes at least one solid-state battery cell. The solid-state battery cell has a structure in which an anode current collector 13, an anode active material layer 14, a solid electrolyte layer 15, a cathode active material layer 12, and a cathode current collector 11 are stacked in this order. In this embodiment, the power generating element 10 includes only one solid-state battery cell. In other words, the power generating element 10 is a solid-state battery cell. As shown in (b) and (c) of FIG. 1, the power generating element 10 includes a cathode current collector 11, a cathode active material layer 12, an anode current collector 13, an anode active material layer 14, and a solid electrolyte layer 15.

[0045] The positive electrode current collector 11 may be a porous or non-porous sheet or film made of a metal material such as aluminum, stainless steel, titanium, or an alloy thereof. Aluminum and its alloys are inexpensive and easy to form into thin films. The sheet or film may also be a metal foil or mesh.

[0046] The thickness of the positive electrode current collector 11 is, for example, in the range of 1 μm to 30 μm, but is not limited thereto. When the thickness of the positive electrode current collector 11 is 1 μm or more, the mechanical strength is sufficient and cracks or breaks are unlikely to occur. When the thickness of the positive electrode current collector 11 is 30 μm or less, the energy density of the battery 1 can be increased.

[0047] The positive electrode active material layer 12 is provided in contact with the main surface of the positive electrode current collector 11 facing the negative electrode current collector 13. In the present embodiment, the positive electrode active material layer 12 is smaller than the positive electrode current collector 11 in a plan view. The side surface of the positive electrode active material layer 12 is covered with the solid electrolyte layer 15. Note that the positive electrode active material layer 12 may be the same size as the positive electrode current collector 11 in a plan view. The side surface of the positive electrode active material layer 12 and the side surface of the positive electrode current collector 11 may be flush with each other.

[0048] The positive electrode active material layer 12 is a layer containing a positive electrode active material, and may be a positive electrode mixture layer containing a positive electrode active material and a solid electrolyte.

[0049] Examples of the positive electrode active material contained in the positive electrode active material layer 12 include lithium-containing transition metal oxides, transition metal fluorides, polyanions or fluorinated polyanion materials, transition metal sulfides, transition metal oxyfluorides, transition metal oxysulfides, and transition metal oxynitrides. In particular, when lithium-containing transition metal oxides are used as the positive electrode active material particles, the manufacturing cost can be reduced and the average discharge voltage can be increased.

[0050] The thickness of the positive electrode active material layer 12 is, for example, in the range of 10 μm to 500 μm, but is not limited thereto. If the thickness of the positive electrode active material layer 12 is 10 μm or more, the energy density of the battery 1 can be further increased. If the thickness of the positive electrode active material layer 12 is 500 μm or less, operation at a higher output is possible.

[0051] The negative electrode current collector 13 may be a porous or non-porous sheet or film made of a metal material such as stainless steel, nickel, copper, or an alloy thereof. Copper and its alloys are inexpensive and easy to form into thin films. The sheet or film may also be a metal foil or mesh.

[0052] The thickness of the negative electrode current collector 13 is, for example, in the range of 1 μm to 30 μm, but is not limited thereto. When the thickness of the negative electrode current collector 13 is 1 μm or more, the negative electrode current collector 13 has sufficient mechanical strength and is less likely to crack or break. When the thickness of the negative electrode current collector 13 is 30 μm or less, the energy density of the battery can be increased.

[0053] The negative electrode active material layer 14 is provided in contact with the main surface of the negative electrode current collector 13 facing the positive electrode current collector 11. In the present embodiment, the negative electrode active material layer 14 is smaller than the negative electrode current collector 13 in a plan view. The side surface of the negative electrode active material layer 14 is covered with the solid electrolyte layer 15. The negative electrode active material layer 14 is larger than the positive electrode active material layer 12 in a plan view. The negative electrode active material layer 14 may be the same size as the negative electrode current collector 13 in a plan view. The side surface of the negative electrode active material layer 14 and the side surface of the negative electrode current collector 13 may be flush with each other.

[0054] The negative electrode active material layer 14 is a layer containing a negative electrode active material, and may be a negative electrode mixture layer containing a negative electrode active material and a solid electrolyte.

[0055] The negative electrode active material contained in the negative electrode active material layer 14 is, for example, a material that absorbs and releases metal ions. The negative electrode active material may be, for example, a material that absorbs and releases lithium ions. Examples of the negative electrode active material include lithium metal, metals or alloys that exhibit an alloying reaction with lithium, carbon, transition metal oxides, and transition metal sulfides. Examples of carbon that can be used include graphite, or non-graphitic carbon such as hard carbon or coke. Examples of transition metal oxides that can be used include CuO and NiO. Examples of transition metal sulfides that can be used include copper sulfide represented by CuS. Examples of metals or alloys that exhibit an alloying reaction with lithium include alloys of lithium with silicon compounds, tin compounds, and aluminum compounds. Using carbon can reduce manufacturing costs and increase the average discharge voltage.

[0056] The thickness of the negative electrode active material layer 14 is, for example, in the range of 10 μm to 500 μm, but is not limited thereto. If the thickness of the negative electrode active material layer 14 is 10 μm or more, the energy density of the battery 1 can be further increased. If the thickness of the negative electrode active material layer 14 is 500 μm or less, operation at a higher output is possible.

[0057] The solid electrolyte layer 15 is located between the positive electrode active material layer 12 and the negative electrode active material layer 14 and is in contact with each of them. In the present embodiment, the solid electrolyte layer 15 covers the side surface of the positive electrode active material layer 12 and is in contact with the positive electrode current collector 11. The solid electrolyte layer 15 covers the side surface of the negative electrode active material layer 14 and is in contact with the negative electrode current collector 13. The solid electrolyte layer 15 is smaller than the positive electrode current collector 11 and the negative electrode current collector 13 in a planar view. The solid electrolyte layer 15 may be the same size as the positive electrode current collector 11 and the negative electrode current collector 13 in a planar view. That is, the side surface of the solid electrolyte layer 15 may be flush with the side surfaces of the positive electrode current collector 11 and the negative electrode current collector 13.

[0058] The solid electrolyte layer 15 includes a solid electrolyte.

[0059] The thickness of the solid electrolyte layer 15 is, for example, in the range of 1 μm to 200 μm, but is not limited thereto. If the thickness of the solid electrolyte layer 15 is 1 μm or more, it is possible to suppress short-circuiting between the positive electrode active material layer 12 and the negative electrode active material layer 14. If the thickness of the solid electrolyte layer 15 is 200 μm or less, it is possible to operate at a higher output.

[0060] As the solid electrolyte contained in the positive electrode active material layer 12, the negative electrode active material layer 14, or the solid electrolyte layer 15, for example, a sulfide solid electrolyte, an oxide solid electrolyte, a halide solid electrolyte, a polymer solid electrolyte, or a complex hydride solid electrolyte can be used.

[0061] Examples of sulfide solid electrolytes include Li2S-P2S5, Li2S-SiS2, Li2S-B2S3, Li2S-GeS2, and Li 3.25 Ge 0.25 P 0.75 S4 or Li 10 GeP2S 12 In addition, at least one of these may be LiX (X: F, Cl, Br, I), Li2O, or MO p Or Li q MO r (wherein M is any of P, Si, Ge, B, Al, Ga, In, Fe, and Zn, and p, q, and r are natural numbers), etc. may be added.

[0062] Examples of oxide solid electrolytes include NASICON-type solid electrolytes, such as LiTi2(PO4)3 or its elemental substitution products, (LaLi)TiO3-based perovskite-type solid electrolytes, and Li 14 ZnGeO 16 LISICON-type solid electrolytes, such as Li4SiO4, LiGeO4, or their elemental substitution products, Li7La3Zr2O 12Or, garnet-type solid electrolytes represented by their element substitution products, Li3N or its H-substituted product, Li3PO4 or its N-substituted product, or glass or glass ceramics based on Li-BO compounds such as LiBO2 or Li3BO3 to which Li2SO4 or Li2CO3 etc. has been added can be used.

[0063] The halide solid electrolyte may be, for example, a compound having the composition formula Li α M β X γ A material represented by the formula (1) is used. Here, α, β, and γ are values greater than 0. M includes at least one metal element other than Li and a metalloid element. X is one or more elements selected from the group consisting of Cl, Br, I, and F. Here, the metalloid elements are B, Si, Ge, As, Sb, and Te. Metal elements include all elements in Groups 1 to 12 of the periodic table except for hydrogen, as well as the above-mentioned metalloid elements and all elements in Groups 13 to 16 except for C, N, P, O, S, and Se. In other words, metal elements are a group of elements that can become cations when forming inorganic compounds with halide compounds. Examples of halide solid electrolytes that can be used include Li3YX6, Li2MgX4, Li2FeX4, Li(Al, Ga, In)X4, and Li3(Al, Ga, In)X6.

[0064] As the complex hydride solid electrolyte, for example, LiBH4-LiI or LiBH4-P2S5 can be used.

[0065] As the polymer solid electrolyte, for example, a compound of a polymer compound and a lithium salt can be used. The polymer compound may have an ethylene oxide structure. When the polymer compound has an ethylene oxide structure, it can contain a large amount of lithium salt, thereby further increasing ionic conductivity. As the lithium salt, LiPF6, LiBF4, LiSbF6, LiAsF6, LiSO3CF3, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiN(SO2CF3)(SO2C4F9), LiC(SO2CF3)3, or the like can be used. As the lithium salt, one type of lithium salt selected from these can be used alone. Alternatively, as the lithium salt, a mixture of two or more types of lithium salts selected from these can be used.

[0066] At least one of the positive electrode active material layer 12, the solid electrolyte layer 15, and the negative electrode active material layer 14 may contain a binder to improve adhesion between particles. The binder is used to improve the binding of the materials constituting the electrodes. Examples of binders include polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polymethyl acrylate, polyethyl acrylate, polyhexyl acrylate, polymethacrylic acid, polymethyl methacrylate, polyethyl methacrylate, polyhexyl methacrylate, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, styrene-butadiene rubber, and carboxymethyl cellulose. The binder may be a copolymer of two or more materials selected from tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid, and hexadiene. Alternatively, a mixture of two or more materials selected from these may be used as the binder.

[0067] At least one of the positive electrode active material layer 12 and the negative electrode active material layer 14 may contain a conductive additive to enhance conductivity. Examples of conductive additives that can be used include graphites such as natural graphite or artificial graphite, carbon blacks such as acetylene black or ketjen black, conductive fibers such as carbon fiber or metal fiber, metal powders such as carbon fluoride or aluminum, conductive whiskers such as zinc oxide or potassium titanate, conductive metal oxides such as titanium oxide, and conductive polymer compounds such as polyaniline, polypyrrole, or polythiophene. Using a carbon conductive additive can reduce costs.

[0068] The power generating element 10 has principal surfaces 10a and 10b. The principal surface 10a is an example of a first principal surface and is a surface perpendicular to the stacking direction of the layers constituting the power generating element 10. The principal surface 10a is, for example, the surface of the positive electrode current collector 11 opposite to the surface that contacts the positive electrode active material layer 12. The principal surface 10b is an example of a second principal surface opposite to the first principal surface. The principal surface 10b is, for example, the surface of the negative electrode current collector 13 opposite to the surface that contacts the negative electrode active material layer 14.

[0069] The principal surfaces 10a and 10b have, for example, a rectangular shape in plan view and the same size. However, the principal surfaces 10a and 10b may have another polygonal shape such as a square, or may be a circle in plan view.

[0070] The area of each of the main surfaces 10a and 10b of the power generating element 10 is, for example, 1 cm for a battery for a portable electronic device such as a smartphone or a digital camera. 2 More than 100cm 2 Alternatively, the area of the main surface of the power generating element 10 is in the range of 100 cm2 or less for a battery used as a power source for large mobile devices such as electric vehicles. 2 More than 1000cm 2 The following ranges may also be used:

[0071] [1-3. Pressure-reducing members] Next, the pressure members 20 and 30 will be described.

[0072] The pressure applying member 20 is an example of a first pressure applying member that contacts the main surface 10a of the power generating element 10. The pressure applying member 20 has a gap 21. The gap 21 is an example of a first gap, and includes an extension 42 that is part of the insulating member 40 therein.

[0073] The void 21 is provided in the main surface 20a of the pressing member 20, which is not in contact with the power-generating element 10. Specifically, the void 21 is a recess recessed from the main surface 20a toward the main surface 20b. The main surface 20b is the surface opposite the main surface 20a and is the surface that is in contact with the main surface 10a of the power-generating element 10. The void 21 is a recess that does not penetrate the pressing member 20 in the thickness direction and has a bottom. An extension 42 is provided to cover the bottom of the void 21.

[0074] In this embodiment, the void 21 is a groove extending in one direction. The cross section of the void 21 perpendicular to the extension direction is, for example, rectangular, but is not limited to this. The void 21 may be a V-shaped groove or a U-shaped groove. The width of the void 21 is uniform regardless of the position in the extension direction, but may be non-uniform.

[0075] The voids 21 are continuous from one end to the other end of the pressure member 20 in a direction parallel to the main surface 10a. Specifically, as shown in FIG. 1(a), the voids 21 are continuous from one of the two long sides of the pressure member 20 in a plan view to the other. The voids 21 are parallel to the short sides of the pressure member 20 and extend in the y-axis direction. This allows the length of the voids 21 (y-axis direction) to be shortened, which makes it easier to form the extension portions 42 formed using a resin material with a uniform thickness.

[0076] The extension direction of the voids 21 may be inclined obliquely with respect to the y-axis direction. Alternatively, the voids 21 may be continuous from one of the two short sides of the pressure member 20 to the other. For example, the voids 21 may be parallel to the long sides of the pressure member 20 and extend in the x-axis direction. The extension direction of the voids 21 may be curved.

[0077] In this embodiment, the pressure member 20 has a plurality of voids 21. As shown in FIG. 1(a), the plurality of voids 21 are arranged in a stripe pattern in a plan view. That is, the plurality of voids 21 extend parallel to one another. The interval between two adjacent voids 21 is constant, but may be different. The plurality of voids 21 have the same size and shape, but may be different. The plurality of voids 21 are arranged point-symmetrically with respect to the center of the pressure member 20 in a plan view.

[0078] The pressure applying member 30 is an example of a second pressure applying member that contacts the main surface 10b of the power generating element 10. The pressure applying member 30 has a gap 31. The gap 31 is an example of a second gap, and includes an extension portion 43 that is a part of the insulating member 40 inside.

[0079] The void 31 is provided on the main surface 30a of the pressing member 30, which is not in contact with the power-generating element 10. Specifically, the void 31 is a recess recessed from the main surface 30a toward the main surface 30b. The main surface 30b is the surface opposite the main surface 30a, and is the surface that is in contact with the main surface 10b of the power-generating element 10. The void 31 is a recess that does not penetrate the pressing member 30 in the thickness direction and has a bottom. An extension 43 is provided to cover the bottom of the void 31.

[0080] In this embodiment, the pressure member 30 has a plurality of voids 31. The plurality of voids 31 are arranged in a stripe pattern in a plan view. That is, the plurality of voids 31 extend parallel to one another. The interval between two adjacent voids 31 is constant, but may be different. The plurality of voids 31 have the same size and shape, but may be different.

[0081] The specific configuration of the gap 31 is the same as that of the gap 21. In addition, the modifications applicable to the gap 21 are also applicable to the gap 31.

[0082] The following describes the materials, properties, shapes, etc. that are common to the pressure members 20 and 30. In the following description, the pressure members 20 and 30 will be collectively referred to simply as "pressure members."

[0083] The pressure member is harder than the insulating member 40. The pressure member may be electrically conductive or electrically insulating. The pressure member may also contain resin or metal.

[0084] The resin contained in the pressure member may be a conductive polymer. By imparting conductivity to the pressure member, it can be used as a current collector. If the pressure member also functions as a current collector, the power generating element 10 does not need to include at least one of the positive electrode current collector 11 and the negative electrode current collector 13, and the thickness of the power generating element 10 can be reduced. Reducing the thickness of the power generating element 10 can increase the energy density of the power generating element 10. Note that if the power generating element 10 does not include the positive electrode current collector 11, the main surface of the positive electrode active material layer 12 is the first main surface of the power generating element 10 and is in contact with the pressure member. In other words, the positive electrode active material layer 12 is formed directly on the main surface of the pressure member. The same applies to the case where the power generating element 10 does not include the negative electrode current collector 13.

[0085] The pressure applying member may contain a metal. If the pressure applying member contains a metal, defects such as cracks in the power generating element 10 caused by sudden pressure changes are less likely to occur. Furthermore, by imparting electrical conductivity to the pressure applying member, the pressure applying member can be used as a current collector.

[0086] Examples of the resin contained in the pressure member include organic polymers such as polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polymethyl ester of acrylic acid, polyethyl ester of acrylic acid, hexyl ester of polyacrylic acid, polymethacrylic acid, polymethyl ester of methacrylic acid, polyethyl ester of methacrylic acid, polyhexyl ester of methacrylic acid, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, carboxymethyl cellulose, and epoxy resin.

[0087] The conductive polymer contained in the pressure member may be, for example, polyacetylene, polyaniline, polypyrrole, or polythiophene.

[0088] The metal contained in the pressure member may be, for example, aluminum, stainless steel, titanium, nickel, copper, magnesium, or an alloy thereof.

[0089] The pressure member may contain an inorganic material, such as a simple oxide such as SiO2, MgO, Al2O3, or ZrO2, a composite oxide containing two or more simple oxides, a metal nitride such as AlN or Si3N4, or a metal carbide such as SiC.

[0090] The thickness of the pressure member is in the range of 3 mm to 10 mm, but is not limited thereto. When the thickness of the pressure member is 3 mm or more, mechanical strength is ensured and cracking and deformation are less likely to occur. In addition, the restraining pressure of the pressure member is increased. On the other hand, when the thickness of the pressure member is 10 mm or less, the energy density of the battery 1 can be increased.

[0091] [1-4. Insulating materials] Next, the insulating member 40 will be described.

[0092] As shown in FIG. 1, the insulating member 40 has a side surface portion 41 and extension portions 42 and 43.

[0093] The side surface portion 41 is a portion that covers the side surface 10c of the power-generating element 10. The side surface portion 41 is in contact with the side surface 10c of the power-generating element 10. The side surface portion 41 is provided in a ring shape around the entire periphery of the power-generating element 10 in a plan view, and covers the entire side surface 10c. The side surface portion 41 may cover only a portion of the side surface 10c of the power-generating element 10. For example, the side surface portion 41 may cover only the side surfaces on the two long sides of the power-generating element 10 in a plan view, and not the side surfaces on the short sides.

[0094] The extension portions 42 and 43 are portions that extend from the side surface portion 41 into the interior of the voids 21 and 31, respectively. The extension portion 42 covers the bottom surface of the void 21, which is a groove. The shape of the extension portion 42 in a plan view matches the shape of the void 21 in a plan view. The thickness of the extension portion 42 is uniform, but may be non-uniform. Furthermore, the extension portion 42 may be filled so as to fill the entire void 21.

[0095] The extension portion 43 almost completely fills the groove-like void 31. The planar shape of the extension portion 43 matches the planar shape of the void 31. The extension portion 43 may be included in only a portion of the interior of the void 31, like the extension portion 42.

[0096] The side surface portion 41 and the extension portions 42 and 43 are integrated together. That is, the side surface portion 41 and the extension portions 42 and 43 are integrally formed using the same insulating material. The insulating material is, for example, a resin material, but may also be an inorganic material.

[0097] Examples of resins that can be used in the insulating member 40 include organic polymers such as polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polyacrylic acid methyl ester, polyacrylic acid ethyl ester, polyacrylic acid hexyl ester, polymethacrylic acid, polymethacrylic acid methyl ester, polymethacrylic acid ethyl ester, polymethacrylic acid hexyl ester, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, carboxymethyl cellulose, and epoxy resin.

[0098] Examples of inorganic materials that can be used in the insulating member include simple oxides such as SiO2, MgO, Al2O3, or ZrO2, composite oxides containing two or more simple oxides, metal nitrides such as AlN or Si3N4, and metal carbides such as SiC.

[0099] (Embodiment 2) Next, a second embodiment will be described.

[0100] The battery according to embodiment 2 differs from embodiment 1 mainly in the shape of the voids provided in the pressure member. The following description will focus on the differences from embodiment 1, and descriptions of commonalities will be omitted or simplified.

[0101] Fig. 2 is a top view and a cross-sectional view showing a schematic configuration of a battery 101 according to embodiment 2. Fig. 2(a) is a plan view of the battery 101 as seen from the positive side of the z-axis. Fig. 2(b) is a cross-sectional view taken along line IIb-IIb in Fig. 2(a). Fig. 2(c) is a cross-sectional view taken along line IIc-IIc in Fig. 2(a).

[0102] As shown in FIG. 2, the battery 101 includes a power generating element 10, pressure members 120 and 130, and an insulating member 140.

[0103] The pressure member 120 has a plurality of voids 121. As shown in (a) of FIG. 2, the plurality of voids 121 are arranged in a lattice pattern in a plan view. That is, the plurality of voids 121 includes voids extending in one direction and voids extending in a direction intersecting the one direction. In this embodiment, the plurality of voids 121 extend along either the x-axis direction or the y-axis direction. That is, the plurality of voids 121 extend along either the short side or the long side of the pressure member 120 in a plan view. Note that the plurality of voids 121 may also be arranged in a lattice pattern in which the voids intersect diagonally in a plan view.

[0104] The pressure member 130 has a plurality of voids 131. Similar to the voids 121, the plurality of voids 131 are arranged in a lattice pattern in plan view. The specific configuration of the voids 131 is the same as that of the voids 121. In addition, the modifications applicable to the voids 121 are also applicable to the voids 131.

[0105] The outlines of the plurality of voids 131 and the plurality of voids 121 may be the same in a plan view. Alternatively, the extending direction of the voids 131 and the extending direction of the voids 121 may be different. For example, the extending direction of the voids 131 and the extending direction of the voids 121 may intersect at an intersecting angle of 45°. The magnitude of the intersecting angle is not particularly limited.

[0106] The insulating member 140 has a side surface portion 41 and extending portions 142 and 143. The extending portions 142 and 143 are located inside the gaps 121 and 131, respectively. Therefore, the extending portions 142 and 143 each have a lattice shape in plan view. In other words, the extending portions 142 and 143 form a mesh body, which makes it easier to apply uniform pressure to the pressure members 120 and 130 within the plane. Therefore, the restraining pressure applied to the power generating element 10 via the pressure members 120 and 130 can be made nearly uniform within the plane.

[0107] The battery 101 according to this embodiment may include a pressure member 20 instead of the pressure member 120. Alternatively, the battery 101 may include a pressure member 30 instead of the pressure member .

[0108] (Embodiment 3) Next, a third embodiment will be described.

[0109] The battery according to embodiment 3 differs from embodiments 1 and 2 mainly in that the gaps provided in the pressure member are through-holes. The following description will focus on the differences from embodiments 1 and 2, and will omit or simplify the description of the commonalities.

[0110] Fig. 3 is a cross-sectional view showing a schematic configuration of a battery 201 according to embodiment 3. Fig. 3(a) is a cross-sectional view taken along line IIIa-IIIa in Fig. 3(b). Fig. 3(b) is a cross-sectional view taken along line IIIb-IIIb in Fig. 3(a). Fig. 3(c) is a cross-sectional view taken along line IIIc-IIIc in Fig. 3(a).

[0111] As shown in FIG. 3, the battery 201 includes the power generating element 10, pressure members 220 and 230, and an insulating member 240.

[0112] The pressure applying member 220 has a plurality of voids 221. As shown in Figures 3(b) and 3(c), each of the plurality of voids 221 is a through-hole that penetrates the pressure applying member 220 in a direction parallel to the main surface 10a of the power generating element 10. The voids 221 penetrate from one end to the other end of the pressure applying member 220 in a plan view.

[0113] 3(a), the plurality of voids 221 are arranged in a lattice pattern in plan view. That is, the plurality of voids 221 include through holes that penetrate the pressure member 220 in one direction and through holes that penetrate in a direction intersecting the one direction. In this embodiment, the plurality of voids 221 penetrate the pressure member 220 along either the x-axis direction or the y-axis direction. That is, the plurality of voids 221 penetrate along either the short side or the long side of the pressure member 220 in plan view. Note that the plurality of voids 221 may also be arranged in a lattice pattern that intersects at an angle in plan view.

[0114] The cross-sectional shape of void 221 perpendicular to the extension direction is circular, but is not limited to this. The cross-sectional shape of void 221 may be a polygon such as a square or a rectangle, or may be an ellipse. Furthermore, the cross-sectional area of void 221 is uniform regardless of the position in the extension direction, but may be non-uniform.

[0115] The pressure member 230 has a plurality of voids 231. Similar to the voids 221, each of the plurality of voids 231 is a through-hole that penetrates the pressure member 230 in a direction parallel to the main surface 10b of the power generating element 10. The specific configuration of the voids 231 is the same as that of the voids 221. In addition, the modifications that can be applied to the voids 221 can also be applied to the voids 231.

[0116] The insulating member 240 has a side surface portion 41 and extending portions 242 and 243. The extending portions 242 and 243 are located inside the voids 221 and 231, respectively. The extending portions 242 and 243 completely fill the interiors of the voids 221 and 231, respectively. Note that at least one of the voids 221 and 231 may include a portion where the extending portion 242 or 243 is not present.

[0117] The voids 221 and 231 may be provided in a stripe pattern in plan view, similar to the voids 21 and 31 according to the first embodiment.

[0118] Furthermore, the battery 201 according to this embodiment may include the pressing member 20 or 120 instead of the pressing member 220. Alternatively, the battery 201 may include the pressing member 30 or 130 instead of the pressing member 230.

[0119] (Fourth embodiment) Next, a fourth embodiment will be described.

[0120] The battery according to embodiment 4 differs from embodiments 1 to 3 mainly in that the power generating element includes a plurality of solid-state battery cells connected in parallel. The following description will focus on the differences from embodiments 1 to 3, and the description of the commonalities will be omitted or simplified.

[0121] Fig. 4 is a cross-sectional view showing a schematic configuration of a battery 301 according to embodiment 4. The battery 301 includes a power generating element 310 including at least two solid-state battery cells. In the example shown in Fig. 4, the power generating element 310 includes four solid-state battery cells 10A, 10B, 10C, and 10D. Each of the four solid-state battery cells 10A, 10B, 10C, and 10D has the same configuration as the power generating element 10 according to embodiment 1.

[0122] The solid-state battery cells 10A and 10D are located at both ends in the stacking direction (z-axis direction) in the power generating element 310. The power generating element 310 has main surfaces 310a and 310b.

[0123] The principal surface 310a is an example of a first principal surface, and is a surface perpendicular to the stacking direction of the layers constituting the power generating element 310. In this embodiment, the principal surface 310a is, for example, the surface of the positive electrode current collector 11 of the solid state battery cell 10A opposite to the surface in contact with the positive electrode active material layer 12.

[0124] The principal surface 310b is an example of a second principal surface opposite to the first principal surface. The principal surface 310b is, for example, the surface of the positive electrode current collector 11 of the solid state battery cell 10D opposite to the surface in contact with the positive electrode active material layer 12.

[0125] The four solid-state battery cells 10A, 10B, 10C, and 10D are connected in parallel to one another. Here, parallel connection means that the positive electrode current collectors or the negative electrode current collectors of two adjacent solid-state battery cells are in direct contact with each other, and the positive electrode current collectors included in the solid-state battery cell group (i.e., the power generating element 310) are connected to each other by a positive electrode current collector terminal (not shown), and the negative electrode current collectors included in the power generating element group are connected to each other by a negative electrode current collector terminal (not shown). By connecting multiple solid-state battery cells in parallel, the capacity of the battery 301 can be increased.

[0126] The number of solid-state battery cells connected in parallel is not particularly limited. For example, the number of parallel connections in the power generating element 310 may be 2, 3, or 5 or more. The capacity of the battery 301 can be increased as the number of parallel connections increases. The number of parallel connections may be set to any number taking into consideration ease of handling when manufacturing the all-solid-state battery or the loading space of the device using the all-solid-state battery. For example, the battery 301 may have 10 to 500 solid-state battery cells connected in parallel.

[0127] As described above, when the power generating element 310 including a plurality of solid-state battery cells is constrained, the thickness of the power generating element 310 increases compared to when a single solid-state battery cell is included. This makes it easier for pressure loss to occur inside the group of solid-state battery cells. To prevent deterioration of charge / discharge characteristics due to pressure loss, the power generating element 310 needs to be constrained with a stronger constraining force compared to when a single solid-state battery cell is included.

[0128] A battery 301 according to this embodiment includes pressure members 20 and 30 and an insulating member 340. The pressure member 20 contacts a main surface 310a of the power generating element 310. The pressure member 30 contacts a main surface 310b of the power generating element 310.

[0129] The insulating member 340 has a side surface portion 341 and extension portions 42 and 43. The side surface portion 341 covers the side surface 310c of the power generating element 310. The side surface 310c extends across the multiple solid-state battery cells 10A, 10B, 10C, and 10D. In other words, the side surface portion 341 collectively covers the side surfaces of the multiple solid-state battery cells 10A, 10B, 10C, and 10D.

[0130] As described above, even in the case of the battery 301 including the power generating element 310 including a plurality of stacked solid-state battery cells, the insulating member 340 can apply a restraining pressure to the pressure members 20 and 30 arranged above and below the power generating element 310. This makes it possible to collectively restrain the plurality of solid-state battery cells in the stacking direction, thereby improving the charge / discharge characteristics.

[0131] When the power generating element 310 includes a plurality of solid-state battery cells, adjacent solid-state battery cells may share a positive electrode current collector or a negative electrode current collector. For example, in the case of the battery 301 shown in Fig. 4, the negative electrode current collector 13 of the solid-state battery cell 10A and the negative electrode current collector 13 of the solid-state battery cell 10B may be realized by a single current collector.

[0132] (Embodiment 5) Next, a fifth embodiment will be described.

[0133] The battery according to embodiment 5 differs from embodiments 1 to 4 mainly in that the power generating element includes a plurality of solid-state battery cells connected in series. The following description will focus on the differences from embodiments 1 to 4, and the description of the commonalities will be omitted or simplified.

[0134] Fig. 5 is a cross-sectional view showing a schematic configuration of a battery 401 according to the fifth embodiment. The battery 401 includes a power generating element 410 including at least two solid-state battery cells. In the example shown in Fig. 5, the power generating element 410 includes four solid-state battery cells 10A, 10B, 10C, and 10D. The power generating element 410 differs from the power generating element 310 according to the fourth embodiment in the electrical connection of the solid-state battery cells.

[0135] The power generating element 410 has two main surfaces 410a and 410b.

[0136] The principal surface 410a is an example of a first principal surface, and is a surface perpendicular to the stacking direction of the layers constituting the power generating element 410. In this embodiment, the principal surface 410a is, for example, the surface of the positive electrode current collector 11 of the solid state battery cell 10A opposite to the surface in contact with the positive electrode active material layer 12.

[0137] The principal surface 410b is an example of a second principal surface opposite to the first principal surface. The principal surface 410b is, for example, the surface of the negative electrode current collector 13 of the solid state battery cell 10D opposite to the surface in contact with the negative electrode active material layer 14.

[0138] Specifically, the four solid-state battery cells 10A, 10B, 10C, and 10D are connected in series with each other. Here, "series connection" means that the positive electrode current collectors and negative electrode current collectors of two adjacent solid-state battery cells are in direct contact with each other. By connecting multiple solid-state battery cells in series, the voltage of the battery 401 can be increased.

[0139] The number of solid-state battery cells connected in series is not particularly limited. For example, the number of solid-state battery cells connected in series in the power generating element 410 may be 2 or 3, or may be 5 or more. The more the number of series connections increases, the higher the voltage of the battery 401 can be. The number of series connections may be set to any number taking into consideration ease of handling when manufacturing the all-solid-state battery, the loading space of the device using the all-solid-state battery, the control voltage of the device using the all-solid-state battery, and the like. For example, the battery 401 may have 2 to 500 solid-state battery cells connected in series.

[0140] A battery 401 according to this embodiment includes pressing members 20 and 30 and an insulating member 340. The pressing member 20 contacts a main surface 410a of the power generating element 310. The pressing member 30 contacts a main surface 410b of the power generating element 310. As in the third embodiment, the insulating member 340 has a side surface portion 341 that covers a side surface 410c of the power generating element 410. The side surface 410c extends across the multiple solid-state battery cells 10A, 10B, 10C, and 10D. In other words, the side surface portion 341 collectively covers the side surfaces of the multiple solid-state battery cells 10A, 10B, 10C, and 10D.

[0141] As described above, even in the case of the battery 401 including the power generating element 410 including a plurality of stacked solid-state battery cells, the insulating member 340 can apply a restraining pressure to the pressure members 20 and 30 arranged above and below the power generating element 410. This makes it possible to collectively restrain the plurality of solid-state battery cells in the stacking direction, thereby improving the charge / discharge characteristics.

[0142] When the power generating element 410 includes a plurality of solid-state battery cells, adjacent solid-state battery cells may share a positive electrode current collector or a negative electrode current collector. For example, in the case of the battery 401 shown in Fig. 5, the negative electrode current collector 13 of the solid-state battery cell 10A and the positive electrode current collector 11 of the solid-state battery cell 10B may be realized by a single bipolar current collector.

[0143] A bipolar current collector is an electrode that functions as both a positive electrode current collector and a negative electrode current collector. By using a bipolar current collector, a structure consisting of two current collectors, a positive electrode current collector and a negative electrode current collector, can be realized with a single bipolar current collector. By reducing the number of current collectors, the thickness of the power generating element 410 can be reduced, and the energy density of the battery 401 can be increased.

[0144] The bipolar current collector may be a porous or non-porous sheet or film made of a metal material such as stainless steel, nickel, copper, or an alloy thereof. The sheet or film may be a metal foil or mesh.

[0145] The thickness of the bipolar current collector is in the range of 1 μm to 30 μm, but is not limited thereto. If the thickness of the bipolar current collector is 1 μm or more, it has sufficient mechanical strength and is less likely to crack or break. If the thickness of the bipolar current collector is 30 μm or less, the energy density of the battery 401 can be increased.

[0146] (Battery manufacturing method) The manufacturing method of the battery according to each of the above-mentioned embodiments will be described below with reference to Fig. 6A to Fig. 6D. Fig. 6A to Fig. 6D are cross-sectional views showing each step of the manufacturing method of the battery according to the present embodiment. The manufacturing method of the battery 201 according to embodiment 3 will be described below as an example, but the same applies to the other batteries.

[0147] [Placement process] 6A, a pressing member 220 is placed so as to contact the main surface 10a of the power-generating element 10, and a pressing member 230 is placed so as to contact the main surface 10b of the power-generating element 10. Gaps 221 and 231 are formed in the pressing members 220 and 230, respectively. For example, the pressing member 230, the power-generating element 10, and the pressing member 220 are placed in this order on the bottom surface of the support container 500.

[0148] It should be noted that pressure member 220 having voids 221 is formed, for example, by integral molding using the material that constitutes pressure member 220. Alternatively, the material that constitutes pressure member 220 may be processed into a flat plate shape, and then voids 221 may be formed by cutting or the like. The same applies to pressure member 230.

[0149] [Pressure process] 6B, the power generating element 10 is sandwiched between the pressure members 220 and 230 and pressurized. Specifically, the power generating element 10 is pressed in the stacking direction using a pressing jig 510. The pressing jig 510 is in surface contact with the upper surface of the pressure member 220 and covers the entire upper surface, for example.

[0150] The pressure applied at this time applies a uniform pressure to the entire surface of the power generating element 10. The pressure may be applied by any suitable method, such as mechanical pressure using a pressing jig 510 or gas pressure. Mechanical pressure is, for example, a method in which motor drive is converted into pressure in the stacking direction of the power generating element 10 via a ball screw or hydraulics, and pressure is applied using this pressure. Gas pressure is, for example, a method in which pressurization is applied in the stacking direction of the power generating element 10 using pressurized gas filled in a gas cylinder.

[0151] The pressure applied in the pressurizing step is, for example, 1 MPa or more, but is not limited to this. The pressure may be 5 MPa or more, 10 MPa or more, or 15 MPa or more. The pressure applied in the pressurizing step is, for example, 95 MPa or less, but is not limited to this. For example, the pressure may be 90 MPa or less, 85 MPa or less, or 80 MPa or less.

[0152] [Injection process] Next, as shown in FIG. 6C , while applying pressure, a fluid insulating material 240a is placed so as to cover the side surface 10c of the power generating element 10 and to be contained within the gaps 221 and 231. Specifically, while maintaining the pressure applied in the pressurizing step, the nozzle 520 is used to inject the insulating material 240a so as to cover the periphery of the power generating element 10. At this time, the support container 500 functions as a frame material for holding the insulating material 240a. The insulating material 240a is injected into the gaps 221 and 231 formed in the pressure members 220 and 230.

[0153] The frame material may be separate from the support container 500. The frame material is made of a general-purpose metal such as aluminum or stainless steel, or a special steel containing carbon, etc. The frame material is removed after the insulating material 240a has hardened.

[0154] The terminals (not shown) of the power generating element 10 may be connected by any means that can prevent physical contact between the positive and negative electrodes and maintain insulation.

[0155] The insulating material 240a may be selected so that its viscosity is not excessively high during injection, ensuring ease of injection and that it reaches the planar end of the power-generating element 10 to be protected. The viscosity of the insulating material 240a is, for example, but not limited to, 200 mPa·s or less at 25°C. The viscosity of the insulating material 240a may be, for example, 150 mPa·s or less, 100 mPa·s or less, 50 mPa·s or less, 30 mPa·s or less, or 20 mPa·s or less at 25°C. Furthermore, when a thermosetting resin is selected, the viscosity of the insulating material 240a may be, for example, but not limited to, 200 mPa·s or less at 60°C. The viscosity of the insulating material 240a may be, for example, 150 mPa·s or less, 100 mPa·s or less, 50 mPa·s or less, 30 mPa·s or less, or 20 mPa·s or less at 60°C.

[0156] The insulating material 240a has a low viscosity of, for example, 200 cps or less at 25° C. or 60° C. when injected, and may be a hardening resin.

[0157] [Curing process] Next, as shown in Fig. 6D, the insulating material 240a is hardened while applying pressure. The hardening is performed appropriately depending on the type of hardenable resin used. The hardening process may be performed by heating or leaving it at room temperature, for example.

[0158] After going through the above steps, even when the pressure is released, the battery 201 is maintained in a pressurized state by the pressure members 220 and 230 and the insulating member 240. Therefore, good battery characteristics can be maintained even without a restraining jig.

[0159] In the manufacturing methods of the batteries 1 and 101 according to the first and second embodiments, the pressure members 20 and 30, or the pressure members 120 and 220, may be used in place of the pressure members 220 and 230 in the above-mentioned arrangement step. In the manufacturing methods of the batteries 301 and 401 according to the fourth and fifth embodiments, the power generating element 10 may be replaced by the power generating element 310 or 410, i.e., a plurality of stacked solid-state battery cells, in the above-mentioned arrangement step.

[0160] (Other embodiments) While the batteries and battery manufacturing methods according to one or more aspects have been described based on the embodiments, the present disclosure is not limited to these embodiments. As long as they do not deviate from the gist of the present disclosure, various modifications conceivable by those skilled in the art to the present embodiments and configurations constructed by combining components of different embodiments are also included within the scope of the present disclosure.

[0161] For example, the pressure applying member may have only one void. For example, the void may be continuous from one end to the other end so as to pass through the center of the pressure applying member in a plan view. In this way, the extending portion of the insulating member passes through the center of the pressure applying member in a plan view, and a restraining pressure can be applied so as to restrain the centers of the two pressure applying members from each other.

[0162] Furthermore, for example, each void does not have to be continuous from one end to the other end of the pressure member. For example, void 21 according to embodiment 1 extends from one end of pressure member 20 to a predetermined position inside in a plan view, but does not have to extend to the other end. In other words, the length of void 21 is shorter than the length of the short side of pressure member 20. For example, the length of void 21 may be shorter than half the length of the short side of pressure member 20. The same applies to void 31 and voids 121 and 131 according to embodiment 2.

[0163] Furthermore, the voids 221 and 231 according to the third embodiment do not have to penetrate through the pressure members 220 and 230, respectively. In other words, the voids 221 and 231 may be recesses recessed from the side surfaces of the pressure members 220 and 230.

[0164] Furthermore, for example, the pressure member may be porous (a porous body).

[0165] Furthermore, for example, the battery according to each embodiment may be housed in an exterior body. The exterior body is arranged so as to cover the entire battery, including the pressure member and the insulating member. As the exterior body, a resin-laminated metal foil having a resin film on one or both sides of a metal foil can be used. An example of the resin-laminated metal foil is a resin-laminated metal foil having a configuration in which a resin film for imparting mechanical strength is laminated on one side of the metal foil and a resin film having heat-sealability is laminated on the opposite side.

[0166] The metal foil in the resin-laminated metal foil is, for example, a foil made of aluminum or an aluminum alloy. The resin film for maintaining mechanical strength is, for example, a film made of polyester or nylon. The resin film having heat-sealability is, for example, a film made of polyolefin such as polyethylene or polypropylene.

[0167] The laminate film constituting the exterior body may be embossed on one or both sides.

[0168] Furthermore, various modifications, substitutions, additions, omissions, etc. can be made to the above-described embodiments within the scope of the claims or their equivalents. [Industrial Applicability]

[0169] The battery according to the present disclosure can be used, for example, as an all-solid-state lithium-ion secondary battery in an automotive battery or various electronic devices. [Explanation of symbols]

[0170] 1, 101, 201, 301, 401 batteries 10, 310, 410 Power generation elements 10A, 10B, 10C, 10D solid-state battery cells 10a, 10b, 20a, 20b, 30a, 30b, 310a, 310b, 410a, 410b Main surface 10c, 310c, 410c side 11 Positive electrode current collector 12 Cathode active material layer 13 Negative electrode current collector 14 Negative electrode active material layer 15 Solid electrolyte layer 20, 30, 120, 130, 220, 230 Pressure member 21, 31, 121, 131, 221, 231 void 40, 140, 240, 340 Insulating material 41, 341 Side part 42, 43, 142, 143, 242, 243 extension 240a insulating material 500 Support container 510 Pressing jig 520 nozzle

Claims

1. a power generating element including at least one solid-state battery cell including a stacked positive electrode, a solid electrolyte layer, and a negative electrode; a first pressure member in contact with a first main surface of the power generating element; a second pressure member that contacts a second main surface of the power generating element opposite to the first main surface; An insulating member; Equipped with the first pressure member has a first gap; the second pressure member has a second gap; The insulating member is a side surface portion covering a side surface of the power generating element; an extension portion extending from the side surface portion into each of the first gap and the second gap; the first pressure member has a plurality of the first gaps, The first voids are arranged in a lattice pattern in a plan view. The extension portions extending into the first gaps have a lattice-like shape in a plan view. battery.

2. The insulating member includes a resin material having insulating properties. The battery of claim 1 .

3. the first pressure member and the second pressure member are each harder than the insulating member; The battery according to claim 1 or 2.

4. the power generating element includes a plurality of the solid-state battery cells, The plurality of solid-state battery cells are stacked in a direction perpendicular to the first main surface. The battery according to any one of claims 1 to 3.

5. the plurality of solid-state battery cells are electrically connected in series; the first pressure member and the second pressure member are electrically conductive; The battery of claim 4.

6. a step of disposing a first pressure member having a first gap so as to contact a first main surface of a power generating element including at least one solid-state battery cell including a stacked positive electrode, a solid electrolyte layer, and a negative electrode, and disposing a second pressure member having a second gap so as to contact a second main surface of the power generating element; a step of applying pressure by sandwiching the power generating element between the first pressure member and the second pressure member; disposing a flowable insulating material so as to cover the side surfaces of the power generating element and to be contained within each of the first gap and the second gap while applying pressure; and curing the insulating material while applying the pressure. the first pressure member has a plurality of the first gaps, The first voids are arranged in a lattice pattern in a plan view. The insulating material extending into the plurality of first voids has a lattice-like shape in a plan view. How batteries are manufactured.

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