Battery

Abstract

This battery includes: a solid battery unit provided with a structure having stacked therein a plurality of power generation element units, that each include a first electrode layer, a second electrode layer, and a first solid electrolyte layer positioned between the first electrode layer and the second electrode layer; and a structure provided with, on a side surface of the solid battery unit, a second solid electrolyte layer that contacts a power generation element unit so as not to contact two or more power generation units of the plurality of power generation units, at least one reference electrode unit that faces the side surface of the solid battery unit across the second solid electrolyte layer and that includes a reference electrode that contacts the second solid electrolyte layer, and an insulation member that is disposed so as to surround the second solid electrolyte layer, in a plan view relative to the side surface of the solid battery unit, and that covers the side surface of the solid battery unit.

Description

[Technical Field]

[0001] The present disclosure relates to batteries. [Background technology]

[0002] Solid-state batteries, which use flame-retardant solid electrolytes instead of the flammable organic solvent-containing electrolytes used in conventional batteries such as non-aqueous electrolyte lithium-ion secondary batteries, offer significant advantages in terms of basic safety performance. Therefore, solid-state batteries are seen as promising next-generation batteries due to their potential in terms of cost and energy density, such as the simplification of safety devices, and the race to develop them is accelerating.

[0003] In particular, it is relatively easy to form a battery configuration in which power generating element parts having positive and negative electrode layers are stacked and connected in series (hereinafter referred to as a bipolar battery) with solid-state batteries, and they are expected to be useful as compact batteries that can output high voltage.In addition, it is relatively easy to form a battery configuration in which power generating element parts are stacked and connected in parallel with solid-state batteries, and they are expected to be useful as compact, high-capacity batteries.

[0004] Furthermore, if it is possible to measure the electrical characteristics, such as the potential of each electrode, such as the positive electrode and negative electrode, during actual use of the battery, it will be possible to more accurately understand the electrode state and perform more appropriate battery control based on the measured values, which will make it possible to maintain high performance characteristics and improve performance, such as safety, cycle characteristics, and storage characteristics.

[0005] A three-electrode measurement method using a reference electrode is known as a method for investigating the potential and electrochemical behavior of each electrode. For example, Non-Patent Document 1 describes the configuration of various solid-state batteries capable of three-electrode measurement. Patent Document 1 also discloses a solid-state battery in which a positive electrode current collector, a positive electrode, a solid electrolyte layer, a negative electrode, and a negative electrode current collector are stacked, and which includes a third electrode as a reference electrode in contact with a solid electrolyte layer or a solid electrolyte portion that is provided so as to connect the positive electrode, the solid electrolyte layer, and the negative electrode with a width that matches the length of the side surfaces of the positive electrode, the solid electrolyte layer, and the negative electrode. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-20915 [Non-patent literature]

[0007] [Non-Patent Document 1] Electrochemical Society, "Understanding Electrochemical Measurement Methods through Q&A," Mimizukusha, December 2009, p.10 Summary of the Invention [Problem to be solved by the invention]

[0008] To achieve high performance and high energy density in all-solid-state batteries, it is common to thin and laminate the positive and negative electrodes and the solid electrolyte layer. In order to construct such an all-solid-state battery capable of three-electrode measurements, it is necessary to electrochemically bond and contact the solid electrolyte layer between the battery part and the reference electrode, unlike liquid-based batteries in which electrochemical contact is formed simply by immersing the battery in an electrolyte solution.

[0009] In particular, in batteries in which power generating elements are stacked, it is necessary to arrange a reference electrode including a reference electrode and a solid electrolyte layer for the reference electrode so that adjacent power generating elements in the stacking direction are not connected by the solid electrolyte layer for the reference electrode in order to improve measurement accuracy and prevent short circuits. Also, in batteries in which the positive and negative electrodes and solid electrolyte layers are thinned and stacked, the reference electrode must also be thinned. In conventional structures, the reference electrode may be easily damaged, and therefore improved reliability is also required for batteries capable of three-electrode measurement.

[0010] Therefore, the present disclosure provides a highly reliable battery that allows the electrical characteristics of the electrodes to be measured. [Means for solving the problem]

[0011] A battery according to one embodiment of the present disclosure includes: a solid-state battery unit having a structure in which a plurality of power generation element units are stacked, each of which has a first electrode layer, a second electrode layer, and a first solid electrolyte layer located between the first electrode layer and the second electrode layer; a second solid electrolyte layer that contacts a power generation element unit on a side surface of the solid-state battery unit without contacting two or more of the plurality of power generation element units; at least one reference electrode unit that faces the side surface of the solid-state battery unit across the second solid electrolyte layer and includes a reference electrode that contacts the second solid electrolyte layer; and a structure that has an insulating member that is arranged to surround the second solid electrolyte layer in a plan view of the side surface of the solid-state battery unit and covers the side surface of the solid-state battery unit. [Effects of the Invention]

[0012] According to the present disclosure, the electrical characteristics of electrodes can be measured, and a highly reliable battery can be provided. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic configuration of a battery according to an embodiment. [Figure 2A] FIG. 2A is a side view showing a schematic configuration of a battery according to an embodiment. [Figure 2B] FIG. 2B is a side view showing the battery shown in FIG. 2A with the reference electrode current collector removed. [Figure 3A] FIG. 3A is a diagram illustrating a method for manufacturing a battery according to an embodiment. [Figure 3B] FIG. 3B is a diagram for explaining a method for manufacturing a battery according to an embodiment. [Figure 3C] FIG. 3C is a diagram illustrating a method for manufacturing a battery according to an embodiment. [Figure 3D] FIG. 3D is a diagram illustrating a method for manufacturing a battery according to an embodiment. [Figure 4] FIG. 4 is a diagram for explaining a method for measuring the electrical characteristics of a battery according to an embodiment. [Figure 5A]FIG. 5A is a side view showing a schematic configuration of a battery according to a first modification of the embodiment. [Figure 5B] FIG. 5B is a side view showing the battery shown in FIG. 5A with the reference electrode current collector removed. [Figure 6] FIG. 6 is a cross-sectional view showing a schematic configuration of a battery according to the second modification of the embodiment. [Figure 7] FIG. 7 is a cross-sectional view showing a schematic configuration of a battery according to a third modification of the embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing a schematic configuration of a battery according to a fourth modification of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] (Summary of the Disclosure) An outline of one aspect of the present disclosure is as follows.

[0015] A battery according to one embodiment of the present disclosure includes: a solid-state battery unit having a structure in which a plurality of power generation element units are stacked, each of which has a first electrode layer, a second electrode layer, and a first solid electrolyte layer located between the first electrode layer and the second electrode layer; a second solid electrolyte layer that contacts a power generation element unit on a side surface of the solid-state battery unit without contacting two or more of the plurality of power generation element units; at least one reference electrode unit that faces the side surface of the solid-state battery unit across the second solid electrolyte layer and includes a reference electrode that contacts the second solid electrolyte layer; and a structure that has an insulating member that is arranged to surround the second solid electrolyte layer in a plan view of the side surface of the solid-state battery unit and covers the side surface of the solid-state battery unit.

[0016] As a result, the insulating member arranged to surround the second solid electrolyte layer can increase the mechanical strength of the reference electrode section used to measure the electrical characteristics of each electrode layer. Furthermore, by having the insulating member surround the second solid electrolyte layer and cover the side surface of the solid battery section, electrical and ionic short circuits between the reference electrode section and the solid battery section, and between the multiple power generating element sections of the solid battery section, can be suppressed. This allows the electrical characteristics of the electrodes to be measured, resulting in a highly reliable battery.

[0017] Furthermore, for example, the at least one reference electrode portion may be a plurality of reference electrode portions, and the second solid electrolyte layers included in each of the plurality of reference electrode portions may each be in contact with a different one of the plurality of power generation element portions, and the insulating member may be arranged to surround each of the second solid electrolyte layers in a plan view of a side surface of the solid battery portion.

[0018] This allows the electrical characteristics of the electrode layer of each of the plurality of power generating element sections to be measured individually.

[0019] Furthermore, for example, the insulating members arranged to surround each of the plurality of second solid electrolyte layers may be connected to each other.

[0020] This allows, for example, the insulating member to be formed integrally, thereby increasing the mechanical strength of the structure.

[0021] Furthermore, for example, the plurality of second solid electrolyte layers may include two second solid electrolyte layers in contact with adjacent power generating element units among the plurality of power generating element units, and the two second solid electrolyte layers may not overlap when viewed from the stacking direction of the solid battery units.

[0022] This allows the distance between the two second solid electrolyte layers to be increased, thereby preventing the two second solid electrolyte layers from coming into contact with each other.

[0023] Furthermore, for example, the second solid electrolyte layers may each have portions that do not overlap with each other when viewed along the stacking direction of the solid battery portion.

[0024] As a result, even if a conductive member or the like is extended from each reference electrode portion along the surface of the insulating member in the stacking direction of the solid-state battery portion, the conductive member or the like will not collide with other reference electrode portions, and the structure of the connection portion for electrical connection with each reference electrode portion can be simplified.

[0025] Furthermore, for example, the number of the plurality of second solid electrolyte layers may be four or more, and the plurality of second solid electrolyte layers may be arranged on the side surface of the solid battery section so as to form a plurality of rows extending along a direction that is not perpendicular to the stacking direction of the solid battery section.

[0026] This allows the second solid electrolyte layers to be distributed across multiple rows and arranged in a uniform pattern, thereby enabling the second solid electrolyte layers to be arranged compactly while increasing the mechanical strength of the structure.

[0027] Furthermore, for example, the plurality of power generating element sections may be electrically connected in series and stacked.

[0028] This allows the electrical characteristics of the electrodes to be measured in a series-stacked battery capable of outputting a high voltage, thereby improving reliability.

[0029] Furthermore, for example, the plurality of power generating element sections may be electrically connected in parallel and stacked.

[0030] This allows the electrical characteristics of the electrodes to be measured in a high-capacity parallel-stacked battery, improving reliability.

[0031] Furthermore, for example, the plurality of power generating element units may be electrically connected in parallel and stacked, and the reference electrodes of two or more of the plurality of reference electrode units may be connected to each other. Furthermore, for example, the plurality of power generating element units may be electrically connected in parallel and stacked, and each of the plurality of reference electrode units may further include a reference electrode current collector in contact with the reference electrode, and at least one of the reference electrodes of two or more of the plurality of reference electrode units and the reference electrode current collectors of the two or more reference electrode units may be connected to each other.

[0032] This allows the structure of the structure to be simplified and the mechanical strength of the structure to be increased.

[0033] Furthermore, for example, the insulating member may include an insulating resin.

[0034] The side surface of the solid-state battery section often has minute irregularities resulting from the materials of each layer of the power generating element section, and the bonding anchor effect between such irregularities and the insulating resin of the insulating member can improve the bonding between the solid-state battery section and the structure, thereby increasing the mechanical strength of the battery and firmly protecting the second solid electrolyte layer with the insulating member, thereby improving the reliability of the battery.

[0035] Furthermore, for example, in a plan view of the side surface of the solid-state battery unit, the structure may not extend beyond both ends of the solid-state battery unit in the stacking direction of the solid-state battery unit.

[0036] As a result, even if the solid state battery section is pressurized in the stacking direction to maintain the performance of the power generating element section, the structure is less likely to interfere with the pressure, and deterioration of the battery characteristics of the solid state battery section can be suppressed.

[0037] Furthermore, for example, the length of the structure in the stacking direction of the solid-state battery unit may be smaller than the length of the solid-state battery unit in the stacking direction of the solid-state battery unit.

[0038] As a result, the structure is positioned more inward than the solid battery section in the stacking direction of the solid battery section, so even if the solid battery section is compressed in the stacking direction when pressure is applied from the stacking direction, the compression of the solid battery section is less likely to be hindered, and the battery characteristics of the solid battery section can be improved.

[0039] Hereinafter, the embodiments will be specifically described with reference to the drawings.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] In addition, in this specification and drawings, the x-axis, y-axis, and z-axis represent the three axes of a three-dimensional Cartesian coordinate system. The x-axis and y-axis correspond to directions parallel to the main surfaces of the current collectors and each layer included in the solid-state battery section, respectively. The z-axis corresponds to the stacking direction of the multiple power generating element sections included in the solid-state battery section and the stacking direction of each layer included in the power generating element section. Furthermore, unless otherwise specified, the "stacking direction" refers to the direction in which each layer in the solid-state battery section is stacked, and corresponds to the direction normal to the main surfaces of the current collectors and each layer included in the solid-state battery section.

[0044] Furthermore, the "plan view" of a certain surface refers to the surface as viewed from the front.

[0045] 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 used not only when two components are arranged closely to each other and are in contact with each other, but also when two components are arranged with a gap between them and another component is present between them.

[0046] (Embodiment) First, the battery according to the embodiment will be described.

[0047] [Battery configuration] First, the configuration of the battery according to this embodiment will be described. FIG. 1 is a cross-sectional view showing a schematic configuration of a battery 500 according to this embodiment. FIG. 2A is a side view showing a schematic configuration of a battery 500 according to this embodiment. FIG. 2A is a plan view of a side surface 100a of a solid-state battery section 100. FIG. 2B is a side view showing a state in which a reference electrode current collector 150 is removed from the battery 500 shown in FIG. 2A. Note that FIG. 1 shows a cross section taken along line II in FIG. 2A. In addition, in FIGS. 2A and 2B, a dotted pattern is applied to the insulating member 190 to make it easier to understand the region in which the insulating member 190 is formed, but this is not intended to mean that the dotted pattern is applied to the actual insulating member 190.

[0048] 1 and 2A, the battery 500 includes a solid-state battery unit 100 having a plurality of power generating element units 50, and a structure 200 having a reference electrode unit 170 and an insulating member 190. The battery 500 is, for example, an all-solid-state battery. The battery 500 is, for example, a coin-type, laminate-type, cylindrical-type, or prismatic-type battery.

[0049] The solid-state battery unit 100 has a plurality of power generating element units 50, a positive electrode current collector 60, and a negative electrode current collector 70. The solid-state battery unit 100 has a structure in which a plurality of power generating element units 50 are stacked. In the illustrated example, the solid-state battery unit 100 has five power generating element units 50, but there is no limit to the number of power generating element units 50, and the solid-state battery unit 100 may have two or more power generating element units 50. The solid-state battery unit 100 may have four or more power generating element units 50. The shape of the solid-state battery unit 100 is, for example, a rectangular parallelepiped, a polygonal prism, or a cylinder.

[0050] The side surface 100a of the solid-state battery unit 100 contacts the structure 200. Specifically, the side surface 100a contacts the second solid electrolyte layer 130 and the insulating member 190. The side surface of the solid-state battery unit 100 and each component of the solid-state battery unit 100 is a surface connecting two opposing main surfaces of the solid-state battery unit 100 and each component of the solid-state battery unit 100, and is, for example, a surface parallel to the stacking direction. The side surface 100a may be inclined with respect to the stacking direction.

[0051] The plurality of power generating element units 50 are electrically connected in series and stacked. This allows for the realization of a battery 500 that can output a high voltage. Furthermore, among the plurality of power generating element units 50, adjacent power generating element units 50 are stacked with a positive electrode current collector 60 and a negative electrode current collector 70 interposed therebetween. The plurality of power generating element units 50 are stacked such that the positive electrode layer 10 of one of the adjacent power generating element units 50 and the negative electrode layer 20 of the other are electrically connected via the current collectors.

[0052] The power generation element unit 50 includes a positive electrode layer 10, an anode layer 20 disposed opposite the positive electrode layer 10, and a first solid electrolyte layer 30 located between the positive electrode layer 10 and the anode layer 20. The positive electrode layer 10 is an example of a first electrode layer, and the anode layer 20 is an example of a second electrode layer. In the power generation element unit 50, the positive electrode layer 10, the first solid electrolyte layer 30, and the anode layer 20 are stacked in this order. The shape of the power generation element unit 50 is, for example, a rectangular parallelepiped, a polygonal pillar, or a cylindrical shape.

[0053] The multiple power generating element units 50 are stacked so that the layers of all the power generating element units 50 are arranged in the same direction. Therefore, in adjacent power generating element units 50, one positive electrode layer 10 and the other negative electrode layer 20 face each other without the first solid electrolyte layer 30 interposed therebetween.

[0054] In each of the multiple power generating element units 50, a positive electrode current collector 60 is laminated on the main surface of the positive electrode layer 10 opposite the first solid electrolyte layer 30, and a negative electrode current collector 70 is laminated on the main surface of the negative electrode layer 20 opposite the first solid electrolyte layer 30. The positive electrode current collector 60 and the negative electrode current collector 70 are disposed between adjacent power generating element units 50. This electrically connects the positive electrode layer 10 of one of the adjacent power generating element units 50 to the negative electrode layer 20 of the other. Note that only one of the positive electrode current collector 60 and the negative electrode current collector 70 may be disposed between adjacent power generating element units 50. In other words, the positive electrode layer 10 may be laminated on one main surface of one positive electrode current collector 60 or one negative electrode current collector 70, and the negative electrode layer 20 may be laminated on the other main surface.

[0055] Furthermore, the positive electrode current collector 60, the negative electrode current collector 70, and the power generation element section 50 located between the positive electrode current collector 60 and the negative electrode current collector 70 constitute a unit battery cell 80. In other words, the unit battery cell 80 has the positive electrode current collector 60, the negative electrode current collector 70, and the power generation element section 50. Therefore, the solid-state battery section 100 has a structure in which a plurality of unit battery cells 80 are stacked such that the opposite poles of adjacent unit battery cells 80 are connected to each other. As a result, the plurality of unit battery cells 80 are electrically connected in series and stacked.

[0056] The positive electrode layer 10 is located between the positive electrode current collector 60 and the first solid electrolyte layer 30 and is in contact with the positive electrode current collector 60 and the first solid electrolyte layer 30 .

[0057] The positive electrode layer 10 includes at least a positive electrode active material. As a material for the positive electrode layer 10, a positive electrode mixture including at least one of a solid electrolyte, a conductive additive, and a binder material may be used in addition to the positive electrode active material, as needed.

[0058] As the positive electrode active material, known materials that can occlude and release (insert and desorb, or dissolve and deposit) metal ions such as lithium ions, sodium ions, magnesium ions, potassium ions, calcium ions, or copper ions can be used.

[0059] Examples of the positive electrode active material include lithium-containing transition metal oxides, lithium-free transition metal oxides, transition metal fluorides, polyanion materials, fluorinated polyanion materials, transition metal sulfides, transition metal oxyfluorides, transition metal oxysulfides, and transition metal oxynitrides. When a lithium-containing transition metal oxide is used as the positive electrode active material, the manufacturing cost of the battery can be reduced and the average discharge voltage of the battery can be increased.

[0060] As the positive electrode active material, in the case of a material capable of extracting and inserting lithium ions, for example, lithium cobalt oxide composite oxide (LCO), lithium nickel oxide composite oxide (LNO), lithium manganese oxide composite oxide (LMO), lithium-manganese-nickel composite oxide (LMNO), lithium-manganese-cobalt composite oxide (LMCO), lithium-nickel-cobalt composite oxide (LNCO), or lithium-nickel-manganese-cobalt composite oxide (LNMCO) can be used. Specific positive electrode active materials include, for example, LiCoO2, LiMn2O4, Li2NiMn3O8, LiVO2, LiCrO2, LiFePO4, LiCoPO4, LiNiO2, and LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2, LiNi x Mn y Al z O2, LiNi x Co y Mn z and LiNi x Co y Al z etc.

[0061] The solid electrolyte may be a known material that conducts metal ions such as lithium ions, sodium ions, magnesium ions, potassium ions, calcium ions, copper ions, or silver ions, or protons, etc. Examples of the solid electrolyte include solid electrolyte materials such as sulfide solid electrolytes, halogen-based solid electrolytes, oxide solid electrolytes, and polymer solid electrolytes.

[0062] As a sulfide solid electrolyte, in the case of a material capable of conducting lithium ions, for example, a compound (Li2S-P2S5) consisting of lithium sulfide (Li2S) and diphosphorus pentasulfide (P2S5) is used. In addition, examples of sulfide solid electrolytes include Li2S-P2S5, Li2S-P2S5-LiBH4, and Li7P3S 11 , Li2S-SiS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li4SiO4, Li2S-B2S3, Li2S-GeS2, Li6PS5Cl, LiSiPSCl, and sulfides containing Li3N or Li3N(H). In addition, as the sulfide solid electrolyte, a sulfide obtained by adding at least one of Li3N, LiCl, LiBr, LiI, Li3PO4, and Li4SiO4 to the above sulfides as an additive may be used. In addition, other specific sulfide solid electrolytes include Li 10 GeP2S 12 (LGPS), Na3Zr2(SiO4)2PO4(NASICON), etc.

[0063] As an oxide solid electrolyte, materials that can conduct lithium ions include, for example, Li7La3Zr2O 12 (LLZ), Li 1.3 Al 0.3 Ti 1.7 (PO4)3(LATP) or (La,Li)TiO3(LLTO) are used.

[0064] A halogen-based solid electrolyte is a solid electrolyte containing a halide. The halide is, for example, a compound consisting of Li, M', and X'. M' is at least one element selected from the group consisting of metal elements and metalloid elements other than Li. X' is at least one element selected from the group consisting of F, Cl, Br, and I. "Metal element" refers to all elements contained in Groups 1 to 12 of the periodic table (excluding hydrogen) and all elements contained in Groups 13 to 16 of the periodic table (excluding B, Si, Ge, As, Sb, Te, C, N, P, O, S, and Se). "Metalloid element" refers to B, Si, Ge, As, Sb, and Te. For example, M' may contain Y (yttrium). Examples of halides containing Y include Li3YCl6 and Li3YBr6.

[0065] Other halides include, for example, Li2MgX'4, Li2FeX'4, Li(Al,Ga,In)X'4, Li3(Al,Ga,In)X'6, LiOX', and LiX'. Specifically, halides include, for example, Li3InBr6, Li3InCl6, Li2FeCl4, Li2CrCl4, Li3OCl, and LiI.

[0066] The polymer solid electrolyte is not particularly limited as long as it is a solid electrolyte containing a polymer material having ion conductivity. Examples of the polymer material having ion conductivity include polyether, polyether derivatives, polyester, and polyimine.

[0067] In addition to the above-mentioned solid electrolyte materials, a thin-film solid electrolyte material such as nitrogen-doped lithium phosphate (LIPON) may also be used as the solid electrolyte.

[0068] In the positive electrode layer 10, the volume ratio of the positive electrode active material to the total volume of the positive electrode active material and the solid electrolyte is, for example, 30% or more and 95% or less. Furthermore, the volume ratio of the solid electrolyte to the total volume of the positive electrode active material and the solid electrolyte is, for example, 5% or more and 70% or less. When the amount of the positive electrode active material and the amount of the solid electrolyte are in such a volume ratio, it becomes easier to ensure a sufficient energy density of the battery 500 and to operate the battery 500 at high output.

[0069] The binder material may be the same as that used in general solid-state batteries, and examples of the binder material include polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyallylic acid, polymethyl acrylate, polyethyl acrylate, polyhexyl acrylate, polymethacrylic acid, polymethyl methacrylate, polyethyl methacrylate, polyhexyl methacrylate, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, styrene-butadiene rubber, carboxymethyl cellulose, polyaniline, polythiophene-styrene-butadiene rubber, and polyacrylate. Furthermore, as the binder material, 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 may be used.

[0070] Examples of conductive additives include graphite such as natural graphite and artificial graphite, carbon black such as acetylene black, furnace black, and Ketjen Black (registered trademark), conductive fibers such as VGCF, carbon nanotubes, carbon nanofibers, fullerenes, carbon fibers, and metal fibers, metal powders such as carbon fluoride and aluminum powder, conductive whiskers such as zinc oxide whiskers and potassium titanate whiskers, conductive metal oxides such as titanium oxide, and conductive polymer compounds such as polyaniline, polypyrrole, and polythiophene.

[0071] The conductive additive may have a shape of, for example, a needle, a scale, a sphere, or an oval sphere. The conductive additive may also be in the form of particles.

[0072] The thickness of the positive electrode layer 10 is, for example, 10 μm or more and 500 μm or less. When the thickness of the positive electrode layer 10 is in this range, it becomes easier to ensure a sufficient energy density of the battery 500 and to operate the battery 500 at high output. In this specification, the thickness of each component of the solid-state battery section 100 is the length of each component in the stacking direction.

[0073] Examples of methods for forming the positive electrode layer 10 include uniaxial compression molding of a powdered positive electrode mixture. Alternatively, the first solid electrolyte layer 30 may be produced by applying a paste-like paint, in which the positive electrode mixture is kneaded with a solvent, onto the substrate, the first solid electrolyte layer 30, the positive electrode current collector 60, or the like, and drying the paint.

[0074] The negative electrode layer 20 is located between the negative electrode current collector 70 and the first solid electrolyte layer 30 and is in contact with the negative electrode current collector 70 and the first solid electrolyte layer 30 .

[0075] The negative electrode layer 20 includes at least a negative electrode active material. As a material for the negative electrode layer 20, in addition to the negative electrode active material, a negative electrode mixture including at least one of a solid electrolyte, a conductive additive, and a binder material may be used as needed.

[0076] The negative electrode active material may be a known material capable of occluding and releasing (inserting and desorbing, or dissolving and depositing) metal ions such as lithium ions, sodium ions, magnesium ions, potassium ions, calcium ions, or copper ions. Examples of the negative electrode active material include metal materials, carbon materials, oxides, nitrides, tin compounds, and silicon compounds.

[0077] As the negative electrode active material, materials capable of extracting and inserting lithium ions are used, such as carbon materials such as natural graphite, artificial graphite, graphite carbon fiber, and resin-baked carbon, metallic lithium, lithium alloys, and oxides of lithium and transition metal elements. Metals used in lithium alloys include indium, aluminum, silicon, germanium, tin, and zinc. Specific examples of oxides of lithium and transition metal elements include Li4Ti5O 12 and Li x SiO and the like.

[0078] The above-described solid electrolyte material can be used as the solid electrolyte of the anode layer 20. The above-described conductive additive can be used as the conductive additive of the anode layer 20. The above-described binder material can be used as the binder material of the anode layer 20.

[0079] In the negative electrode layer 20, the volume ratio of the negative electrode active material to the total volume of the negative electrode active material and the solid electrolyte is, for example, 30% or more and 95% or less. Furthermore, the volume ratio of the solid electrolyte to the total volume of the negative electrode active material and the solid electrolyte is, for example, 5% or more and 70% or less. When the amount of the negative electrode active material particles and the amount of the solid electrolyte are in such a volume ratio, the energy density of the battery 500 can be sufficiently ensured, and the battery 500 can be easily operated at high output.

[0080] The thickness of the negative electrode layer 20 is, for example, 10 μm or more and 500 μm or less. When the thickness of the negative electrode layer 20 is in this range, it becomes easier to ensure a sufficient energy density of the battery 500 and to operate the battery 500 at high output.

[0081] Examples of methods for forming the negative electrode layer 20 include uniaxial compression molding of a powdered negative electrode mixture. Alternatively, the negative electrode layer 20 may be produced by applying a paste-like paint, in which the negative electrode mixture is kneaded with a solvent, onto the substrate, the first solid electrolyte layer 30, the negative electrode current collector 70, or the like, and drying the resulting paint.

[0082] The first solid electrolyte layer 30 is located between the positive electrode layer 10 and the negative electrode layer 20 and is in contact with the positive electrode layer 10 and the negative electrode layer 20 .

[0083] The first solid electrolyte layer 30 has conductivity of metal ions such as lithium ions, sodium ions, magnesium ions, potassium ions, calcium ions, or copper ions. The first solid electrolyte layer 30 may also have lithium ion conductivity.

[0084] The first solid electrolyte layer 30 contains at least a solid electrolyte and may contain a binder material as needed. The first solid electrolyte layer 30 may also contain a solid electrolyte having lithium ion conductivity.

[0085] The above-mentioned solid electrolyte materials can be used as the solid electrolyte of the first solid electrolyte layer 30. One type of solid electrolyte or two or more types of solid electrolytes can be used for the first solid electrolyte layer 30. The above-mentioned binder materials can be used as the binder material of the first solid electrolyte layer 30.

[0086] The thickness of the first solid electrolyte layer 30 is, for example, 0.1 μm or more and 1000 μm or less. From the viewpoint of improving the energy density of the battery 500, the thickness of the first solid electrolyte layer 30 may be 0.1 μm or more and 50 μm or less.

[0087] Examples of methods for forming the first solid electrolyte layer 30 include uniaxial compression molding of a powder of the material containing the first solid electrolyte layer 30. Alternatively, the first solid electrolyte layer 30 may be produced by applying a paste-like paint, in which the material containing the first solid electrolyte layer 30 is kneaded with a solvent, onto the substrate, the positive electrode layer 10, the negative electrode layer 20, or the like, and drying the paint.

[0088] The side surfaces of the positive electrode layer 10, the negative electrode layer 20, and the first solid electrolyte layer 30 are flush with each other and form the side surfaces of the power generation element section 50. Note that the side surfaces of the positive electrode layer 10, the negative electrode layer 20, and the first solid electrolyte layer 30 do not have to be flush with each other. For example, the first solid electrolyte layer 30 may cover the side surfaces of the positive electrode layer 10 and the negative electrode layer 20, and the side surfaces of the power generation element section 50 may be formed only by the side surfaces of the first solid electrolyte layer 30.

[0089] The positive electrode current collector 60 is located on the opposite side of the positive electrode layer 10 from the first solid electrolyte layer 30 side, and is in contact with the positive electrode layer 10. The negative electrode current collector 70 is located on the opposite side of the negative electrode layer 20 from the first solid electrolyte layer 30 side, and is in contact with the negative electrode layer 20.

[0090] Examples of materials for the positive electrode current collector 60 and the negative electrode current collector 70 include highly conductive metal materials such as copper, aluminum, nickel, iron, stainless steel, platinum, gold, an alloy of two or more of these, or a plated version of any of these. The positive electrode current collector 60 and the negative electrode current collector 70 may be made of the same material or different materials.

[0091] There are no particular limitations on the shapes of the positive electrode current collector 60 and the negative electrode current collector 70, as they may be set according to the shape of the battery 500. The shapes of the positive electrode current collector 60 and the negative electrode current collector 70 are, for example, rod-like, plate-like, sheet-like, foil-like, mesh-like, or the like.

[0092] The thickness of the positive electrode current collector 60 and the negative electrode current collector 70 is, for example, 1 μm or more and 10 mm or less. The thickness of the positive electrode current collector 60 and the negative electrode current collector 70 may be 1 μm or more and 50 μm or less. Depending on the shape of the battery 500, the thickness of the positive electrode current collector 60 and the negative electrode current collector 70 may be 10 mm or more.

[0093] The positive electrode layer 10, the negative electrode layer 20, the first solid electrolyte layer 30, the positive electrode current collector 60, and the negative electrode current collector 70 each have a planar shape that is, for example, rectangular, circular, or polygonal. When viewed from the stacking direction, for example, the outer edges of the positive electrode layer 10, the negative electrode layer 20, the first solid electrolyte layer 30, the positive electrode current collector 60, and the negative electrode current collector 70 coincide. However, when viewed from the stacking direction, the outer edges of the positive electrode layer 10, the negative electrode layer 20, the first solid electrolyte layer 30, the positive electrode current collector 60, and the negative electrode current collector 70 do not necessarily have to coincide.

[0094] The structure 200 is provided so as to cover the side surface 100a of the solid-state battery unit 100. When the solid-state battery unit 100 has a rectangular parallelepiped shape, the structure 200 covers, for example, only one side surface 100a of the four side surfaces of the solid-state battery unit 100. One structure 200 is provided on the side surface 100a, but multiple structures 200 each having a reference electrode unit 170 and an insulating member 190 may be provided on the side surface 100a. Furthermore, multiple structures 200 may be provided on two or more of the four side surfaces of the solid-state battery unit 100.

[0095] In a plan view of the side surface 100a of the solid-state battery unit 100, the structure 200 does not protrude beyond both ends of the solid-state battery unit 100 in the stacking direction of the solid-state battery unit 100. In the present embodiment, in a plan view of the side surface 100a, the outermost periphery of the structure 200 is formed of an insulating member 190, and the insulating member 190 does not protrude beyond both ends of the solid-state battery unit 100 in the stacking direction of the solid-state battery unit 100. The length of the structure 200 in the stacking direction of the solid-state battery unit 100 is equal to or less than the length of the solid-state battery unit 100 in the stacking direction of the solid-state battery unit 100. As a result, even when the solid-state battery unit 100 is used while being pressurized in the stacking direction to maintain battery characteristics, the structure 200 is less likely to interfere with the pressure applied to the solid-state battery unit 100, and the pressurized state of the solid-state battery unit 100 is easily maintained. Furthermore, deformation of the structure 200 due to pressure applied to the solid-state battery unit 100 is suppressed, thereby improving the reliability of the battery 500. In this embodiment, the length of the structure 200 in the stacking direction of the solid-state battery units 100 is the same as the length of the solid-state battery units 100 in the stacking direction of the solid-state battery units 100.

[0096] The shape of the structure 200 is, for example, a rectangular parallelepiped, but it may also be a cylindrical or polygonal prism, or may be curved to match the shape of the solid-state battery section 100. Furthermore, a convex portion or a concave portion may be formed on part of the surface of the structure 200.

[0097] The structure 200 includes at least one reference electrode 170 including a second solid electrolyte layer 130, a reference electrode 110, and a reference electrode current collector 150, and an insulating member 190. The second solid electrolyte layer 130, the reference electrode 110, and the reference electrode current collector 150 are arranged in this order along the normal direction of the side surface 100a, away from the side surface 100a. In this embodiment, the structure 200 includes multiple reference electrode 170. The number of the multiple reference electrode 170 is not particularly limited and may be the same as the number of power generating element assemblies 50, for example. One power generating element assemblies 50 are each provided with, for example, one reference electrode 170. For example, to measure the electrical characteristics of the positive electrode layer 10 and the negative electrode layer 20 of each power generating element assemblies 50, at least one reference electrode 170 is provided in each of the multiple power generating element assemblies 50. Note that the multiple power generating element assemblies 50 may include a power generating element assemblies 50 that do not include a reference electrode 170.

[0098] In this embodiment, each of the plurality of reference electrode parts 170 includes a second solid electrolyte layer 130 , a reference electrode 110 , and a reference electrode current collector 150 .

[0099] The second solid electrolyte layer 130 is located between the reference electrode 110 and the solid-state battery portion 100 .

[0100] The second solid electrolyte layer 130 has a first main surface 130a and a second main surface 130b opposite to the first main surface 130a. The first main surface 130a and the second main surface 130b are main surfaces facing back to back. The side surface 100a, the first main surface 130a, and the second main surface 130b are, for example, parallel to each other.

[0101] The second solid electrolyte layer 130 contacts the power generating element 50 at the side surface 100a of the solid battery unit 100 so as not to contact more than one of the multiple power generating element 50. Therefore, the second solid electrolyte layer 130 contacts only one of the multiple power generating element 50 at the side surface 100a. Specifically, the first main surface 130a of the second solid electrolyte layer 130 contacts the side surface of one power generating element 50. The first main surface 130a contacts at least a portion of the side surface of the positive electrode layer 10, the negative electrode layer 20, and the first solid electrolyte layer 30 that constitute one power generating element 50, facing the structure 200. It is sufficient that the first main surface 130a contacts at least one side surface of the positive electrode layer 10, the negative electrode layer 20, and the first solid electrolyte layer 30 that constitute one power generating element 50.

[0102] Furthermore, the first main surface 130a may also be in contact with at least one of the positive electrode current collector 60 and the negative electrode current collector 70 that are in contact with the one power generating element unit 50. The longer the length of the first main surface 130a in the stacking direction of the solid battery units 100, the higher the mechanical strength. The length of the first main surface 130a in the stacking direction of the solid battery units 100 is, for example, equal to or greater than the length of the side surface of the power generating element unit 50 in the stacking direction of the solid battery units 100. The first main surface 130a may be in contact with the positive electrode current collector 60 and the negative electrode current collector 70 that are arranged between the two adjacent power generating element units 50, as long as it is not in contact with the power generating element unit 50 that is located adjacent to the one power generating element unit 50.

[0103] In addition, in a plan view of the side surface 100a, the width of the second solid electrolyte layer 130 is smaller than the width of the power generation element section 50, and the second solid electrolyte layer 130 is located more inward than both ends of the power generation element section 50 in the width direction. Here, the "width" refers to the length in a direction perpendicular to the stacking direction in a plan view of the side surface 100a. Note that in a plan view of the side surface 100a, both ends of the second solid electrolyte layer 130 in the width direction may coincide with both ends of the power generation element section 50 in the width direction.

[0104] The second solid electrolyte layers 130 included in each of the reference electrode sections 170 are each in contact with a different one of the power generating element sections 50. Each of the second solid electrolyte layers 130 is in contact with, for example, one of the power generating element sections 50. The number of the second solid electrolyte layers 130 is the same as the number of the power generating element sections 50. Note that there may be a power generating element section 50 that is not in contact with a second solid electrolyte layer 130.

[0105] 2B, the arrangement of the plurality of second solid electrolyte layers 130 in a plan view relative to the side surface 100a will be described. Because the reference electrode 110 and the reference electrode current collector 150 are arranged on the second solid electrolyte layer 130, the arrangement of the plurality of second solid electrolyte layers 130 also corresponds to the arrangement of the plurality of reference electrode portions 170.

[0106] The second solid electrolyte layers 130 are provided in respective openings 190a formed in the insulating member 190. The openings 190a expose at least a portion of the power generating element units 50 on the side surface 100a of the solid battery unit 100, so that two or more of the power generating element units 50 are not exposed. The second solid electrolyte layer 130 contacts a portion of the area of ​​the side surface 100a exposed by the openings 190a. The second solid electrolyte layer 130 may contact the entire area of ​​the side surface 100a exposed by the openings 190a.

[0107] A reference electrode 110 may be further provided inside the opening 190a, and a reference electrode current collector 150 may also be provided. In the example shown in FIG. 2B, part of the side wall of the opening 190a is open, but the opening 190a may be entirely surrounded by the side wall. Alternatively, the opening 190a may be in the form of a slit sandwiched between the side walls.

[0108] An insulating member 190 is disposed between the plurality of second solid electrolyte layers 130. The plurality of second solid electrolyte layers 130 includes two second solid electrolyte layers 130 that contact adjacent ones of the plurality of power generating element units 50. The two second solid electrolyte layers 130 do not overlap when viewed from the stacking direction of the solid battery unit 100. This increases the distance between the two second solid electrolyte layers 130, thereby preventing the two second solid electrolyte layers 130 from contacting each other. This further improves the reliability of the battery 500.

[0109] In the example shown in FIG. 2B , the number of the second solid electrolyte layers 130 is four or more, specifically five. The second solid electrolyte layers 130 are arranged on the side surface 100 a to form multiple rows L11 and L12 extending in a direction not perpendicular to the stacking direction of the solid battery module 100. The multiple rows L11 and L12 extend along the stacking direction. This allows the multiple second solid electrolyte layers 130 to be distributed among the multiple rows L11 and L12 and arranged in a regular pattern, thereby enabling the multiple second solid electrolyte layers 130 to be arranged compactly while increasing the mechanical strength of the structure 200. In the multiple rows L11 and L12, the multiple second solid electrolyte layers 130 are arranged, for example, at equal intervals. Although the number of the multiple rows L11 and L12 is two in the illustrated example, it may be three or more depending on the number of the multiple second solid electrolyte layers 130.

[0110] The arrangement of the plurality of second solid electrolyte layers 130 (i.e., the arrangement of the plurality of reference electrode portions 170) is not particularly limited, as long as the second solid electrolyte layers 130 of the respective reference electrode portions 170 are arranged so as not to contact each other. For example, the plurality of second solid electrolyte layers 130 may be arranged in a line or randomly. Alternatively, the plurality of second solid electrolyte layers 130 may be arranged in a striped pattern.

[0111] The second solid electrolyte layer 130 may be made of the same material as the first solid electrolyte layer 30. The first solid electrolyte layer 30 and the second solid electrolyte layer 130 may be made of the same material or different materials. The second solid electrolyte layer 130 may be made of one type of solid electrolyte or two or more types of solid electrolytes.

[0112] The thickness of the second solid electrolyte layer 130 is, for example, 10 μm or more and 10 mm or less. The thickness of the second solid electrolyte layer 130 is, for example, greater than the thickness of the first solid electrolyte layer 30. In this specification, the thickness of each component of the structure 200 is the length of each component in the normal direction to the side surface 100 a of the solid battery section 100.

[0113] The reference electrode 110 faces the side surface 100a across the second solid electrolyte layer 130 and is in contact with the second solid electrolyte layer 130. Specifically, the reference electrode 110 is in contact with the second main surface 130b of the second solid electrolyte layer 130. This allows the reference electrode 110 to be ionically connected to the positive electrode layer 10 and the negative electrode layer 20 via the second solid electrolyte layer 130, so that the electrical characteristics of the positive electrode layer 10 and the negative electrode layer 20 can be measured using the reference electrode 110. The reference electrode 110 is surrounded by an insulating member 190 in a plan view of the side surface 100a of the solid battery section 100.

[0114] As shown in FIG. 2B , the area of ​​the reference electrode 110 is smaller than the area of ​​the second main surface 130b in a plan view relative to the second main surface 130b. The area of ​​the reference electrode 110 in a plan view relative to the second main surface 130b is the area of ​​the region surrounded by the outer edge of the reference electrode 110 in a plan view relative to the second main surface 130b. Furthermore, in a plan view relative to the second main surface 130b, the reference electrode 110 is located inside the outer edge of the second main surface 130b. In other words, in a plan view relative to the second main surface 130b, the entire reference electrode 110 is provided on a partial region of the second main surface 130b and is located inside the second main surface 130b. This reduces contact between the reference electrode 110 and the solid-state battery unit 100, thereby suppressing short-circuiting between the reference electrode 110 and the solid-state battery unit 100. The reference electrode 110 may be in contact with the entire second main surface 130b.

[0115] The material of the reference electrode 110 is not particularly limited as long as it is in electrochemical contact with the second solid electrolyte layer 130 and exhibits an equilibrium potential. The reference electrode 110 includes, for example, at least one of metallic lithium, a lithium alloy, and a lithium compound. From the viewpoint of measurement accuracy, a material with a small fluctuation in equilibrium potential may be used as the material of the reference electrode 110. Examples of materials with a small fluctuation in equilibrium potential include metallic lithium, lithium alloys such as In-Li, and Li4Ti5O 12 Examples of lithium compounds include:

[0116] The reference electrode current collector 150 is located on the side of the reference electrode 110 opposite to the second solid electrolyte layer 130 side, and is in contact with the reference electrode 110. The reference electrode current collector 150 covers, for example, the entire surface of the reference electrode 110 opposite to the second solid electrolyte layer 130 side. The position where the reference electrode current collector 150 is in contact with the reference electrode 110 is not particularly limited, and the reference electrode current collector 150 may be in contact with any surface of the reference electrode 110 other than the surface that is in contact with the second solid electrolyte layer 130.

[0117] The surface of the reference electrode current collector 150 opposite to the reference electrode 110 side is exposed to the outside, and is connected to, for example, a terminal or the like for measuring electrical characteristics. Note that the reference electrode part 170 does not necessarily have to include the reference electrode current collector 150, and for example, the electrical characteristics may be measured by directly contacting a terminal or the like with the reference electrode 110.

[0118] In a plan view of the side surface 100a, the outer edge of the reference electrode current collector 150 coincides with, for example, the outer edge of the second solid electrolyte layer 130. That is, in a plan view of the side surface 100a, the reference electrode current collector 150 and the second solid electrolyte layer 130 have the same size. Furthermore, the reference electrode current collector 150 is larger than the reference electrode 110. In a plan view of the side surface 100a, the reference electrode current collector 150 encloses the reference electrode 110. Note that, in a plan view of the side surface 100a, the reference electrode current collector 150 and the second solid electrolyte layer 130 may have different sizes. In a plan view of the side surface 100a, the outer edge of the reference electrode current collector 150 may coincide with the outer edge of the reference electrode 110, or may be located more inward than the outer edge of the reference electrode 110.

[0119] Examples of materials for the reference electrode current collector 150 include highly conductive metal materials such as copper, aluminum, nickel, iron, stainless steel, platinum, or gold, an alloy of two or more of these, or a plated version of any of these.

[0120] The shape of the reference electrode current collector 150 is not particularly limited, as it may be set according to the shape of the structure 200. The shape of the reference electrode current collector 150 is, for example, a rod, plate, sheet, foil, or mesh.

[0121] The thickness of the reference electrode current collector 150 is, for example, 1 μm or more and 20 mm or less. Depending on the shapes of the battery 500 and the structure 200, the thickness of the reference electrode current collector 150 may be 10 mm or more.

[0122] In a plan view of the side surface 100a, the second solid electrolyte layer 130, the reference electrode 110, and the reference electrode current collector 150 each have a shape that is, for example, rectangular, circular, or polygonal. In addition, in a plan view of the side surface 100a, the reference electrode 110 and the reference electrode current collector 150 do not protrude beyond the outer edge of the second solid electrolyte layer 130, for example.

[0123] The insulating members 190 are arranged to surround each of the plurality of second solid electrolyte layers 130 in a plan view relative to the side surface 100a of the solid battery unit 100. The insulating members 190 may be arranged to surround the second solid electrolyte layers 130 from both sides in at least a predetermined direction in a plan view relative to the side surface 100a of the solid battery unit 100. For example, the insulating members 190 surround the second solid electrolyte layer 130 so as to sandwich the second solid electrolyte layer 130 from at least both sides in the stacking direction of the solid battery unit 100. When the second solid electrolyte layer 130 has a rectangular shape in a plan view, the insulating members 190 surround the second solid electrolyte layer 130 so as to cover only two opposing sides and one other side of the second solid electrolyte layer 130, for example, as shown in FIG. 2B . When the second solid electrolyte layer 130 has a rectangular shape in plan view, the insulating member 190 may surround the second solid electrolyte layer 130 so as to cover only two opposing sides thereof, or may surround the second solid electrolyte layer 130 so as to cover all four sides thereof.

[0124] The insulating member 190 is, for example, an insulating member layer whose thickness direction is the normal direction to the side surface 100a. The insulating members 190 arranged to surround each of the plurality of second solid electrolyte layers 130 in a plan view of the side surface 100a are connected. The insulating members 190 are, for example, integrally formed to surround each of the plurality of second solid electrolyte layers 130. This can further increase the mechanical strength of the structure 200. The insulating member 190 may be divided into multiple pieces.

[0125] The insulating member 190 covers, for example, the side surface of the second solid electrolyte layer 130, which is the surface connecting the outer edge of the first main surface 130a and the outer edge of the second main surface 130b. The insulating member 190 is in contact with the side surface of the second solid electrolyte layer 130. The side surface of each component of the structure 200 is, for example, a surface parallel to the normal direction of the side surface 100a of the solid battery section 100. In the illustrated example, the insulating member 190 is in contact with three of the four side surfaces of the second solid electrolyte layer 130. The insulating member 190 is in contact with, for example, at least one of the four side surfaces of the second solid electrolyte layer 130.

[0126] The insulating member 190 covers the side surface 100a of the solid state battery module 100 and is in contact with the side surface 100a. The insulating member 190 covers an area of ​​the side surface 100a that is not in contact with the second solid electrolyte layer 130. The insulating member 190, for example, continuously covers the side surface 100a from one end to the other end in the stacking direction. Note that the insulating member 190 does not necessarily have to cover at least one of the one end and the other end of the side surface 100a in the stacking direction.

[0127] Moreover, the insulating member 190 is disposed so as to surround the reference electrode 110 and the reference electrode current collector 150 in a plan view of the side surface 100a of the solid-state battery section 100. This allows the reference electrode 110 and the reference electrode current collector 150 to be protected by the insulating member 190, further increasing the mechanical strength of the structure 200. As a result, the reliability of the battery 500 can be further improved.

[0128] The insulating member 190 is not in contact with the reference electrode 110, and a gap is provided between the insulating member 190 and the reference electrode 110. The insulating member 190 is also in contact with the reference electrode current collector 150. Note that the insulating member 190 may be in contact with the side surface of the reference electrode 110 so as to fill the gap.

[0129] The thickness of the insulating member 190 is, for example, greater than the sum of the thickness of the second solid electrolyte layer 130 and the thickness of the reference electrode 110. The thickness of the insulating member 190 may be equal to or less than the sum of the thickness of the second solid electrolyte layer 130 and the thickness of the reference electrode 110. The thickness of the insulating member 190 may be, for example, equal to or greater than the thickness of the second solid electrolyte layer 130 and equal to or less than the sum of the thickness of the second solid electrolyte layer 130 and the thickness of the reference electrode 110.

[0130] The insulating member 190 is composed of an insulating material, such as an insulating resin or ceramics. The insulating material used for the insulating member 190 includes, for example, an insulating resin as a main component. The insulating material may further include various resin additives. Examples of insulating resins include epoxy resin, silicone resin, polycarbonate resin, polybutadiene resin, acrylic resin, polyamide resin, and polyacetal resin. The insulating resin may be a thermoplastic resin, a thermosetting resin, or a photocurable resin. The insulating member 190 may include one type of insulating resin or two or more types of insulating resin. The side surface 100a of the solid-state battery unit 100 has fine irregularities derived from the materials of each layer of the power generating element unit 50. When the insulating member 190 includes an insulating resin, the bonding anchor effect between the irregularities and the insulating resin of the insulating member 190 improves the bonding strength between the solid-state battery unit 100 and the structure 200. Therefore, the mechanical strength of the battery 500 is increased, and the second solid electrolyte layer 130 is firmly protected by the insulating member 190, thereby improving the reliability of the battery 500.

[0131] [Battery manufacturing method] Next, a method for manufacturing the battery 500 according to this embodiment will be described. Note that the method for manufacturing the battery 500 is not limited to the following example.

[0132] As a method for manufacturing the battery 500, for example, first, the solid-state battery section 100 is fabricated, and then the structure 200 is formed on the side surface 100a of the fabricated solid-state battery section 100.

[0133] 3A to 3D are cross-sectional views illustrating a method for manufacturing a battery 500. As shown in FIG. 3A, first, a solid-state battery unit 100 is fabricated. The solid-state battery unit 100 can be fabricated using a method similar to that used for general battery manufacturing. For example, the power generating element unit 50 is fabricated by sequentially compressing and compressing powders of materials constituting the positive electrode layer 10, the first solid electrolyte layer 30, and the negative electrode layer 20. Next, a positive electrode current collector 60 is stacked so as to contact the positive electrode layer 10 of the power generating element unit 50, and a negative electrode current collector 70 is stacked so as to contact the negative electrode layer 20 of the power generating element unit 50. A plurality of unit battery cells 80, which are power generating element units 50 each having such a stack of current collectors, are fabricated. The solid-state battery unit 100 is fabricated by stacking these unit battery cells 80 so as to be electrically connected in series.

[0134] Next, as shown in Fig. 3B, an insulating member 190 is formed on the side surface 100a of the fabricated solid-state battery module 100. The insulating member 190 is formed, for example, by applying an insulating resin to the side surface 100a in a pattern that forms openings 190a at desired locations. By applying the insulating resin to the side surface 100a in this way, a bonding anchor effect can be obtained in which the insulating resin penetrates into the irregularities of the side surface 100a.

[0135] Next, as shown in FIG. 3C , second solid electrolyte layer 130 is formed inside opening 190a. Second solid electrolyte layer 130 is formed, for example, by applying a material that constitutes second solid electrolyte layer 130 to an area of ​​side surface 100a that is exposed by opening 190a. Note that second solid electrolyte layer 130 may be formed before forming insulating member 190. In this case, after forming second solid electrolyte layer 130, insulating member 190 is formed so as to surround second solid electrolyte layer 130 formed on side surface 100a in a plan view of side surface 100a.

[0136] 3D, a material for forming the reference electrode 110 is placed or applied on the second solid electrolyte layer 130 formed inside the opening 190a to form the reference electrode 110. Then, a reference electrode current collector 150 is placed in contact with the formed reference electrode 110, thereby manufacturing the battery 500.

[0137] Another method for manufacturing the battery 500 includes separately fabricating the solid-state battery unit 100 and the structure 200, and then pressing the structure 200 against the side surface 100a of the solid-state battery unit 100. Specifically, an insulating member 190 having an opening 190a is prepared, a second solid electrolyte layer 130 is formed inside the opening 190a, and then a reference electrode 110 and a reference electrode current collector 150 are formed to fabricate the structure 200. The fabricated structure 200 is then pressed against the side surface 100a of the solid-state battery unit 100 fabricated by the method described above or the like. At this time, the respective reference electrode portions 170 are pressed against the side surface of the power generating element unit 50 to be measured while being aligned. This allows the battery 500 to be manufactured, and electrochemical contact is formed between the second solid electrolyte layer 130 and the power generating element unit 50.

[0138] [Method for measuring the electrical characteristics of batteries] Next, a method for measuring the electrical characteristics of the battery 500 according to this embodiment will be described. Specifically, a method for measuring the electrical characteristics of the battery 500 including the power generating element section 50 will be described with reference to FIG.

[0139] FIG. 4 is a diagram for explaining a method for measuring the electrical characteristics of the battery 500. In FIG.

[0140] As shown in FIG. 4 , in a battery 500, a voltage measuring device 91 is electrically connected to the positive electrode layer 10 and the negative electrode layer 20 of one of the power generating element units 50 having a reference electrode unit 170 formed on the side surface via a positive electrode current collector 60 and a negative electrode current collector 70. A voltage measuring device 92 is electrically connected to the positive electrode layer 10 and the reference electrode 110 via the positive electrode current collector 60 and the reference electrode current collector 150. A voltage measuring device 93 is electrically connected to the negative electrode layer 20 and the reference electrode 110 via the negative electrode current collector 70 and the reference electrode current collector 150. This allows the measurement of voltage V1 between the positive electrode layer 10 and the negative electrode layer 20, voltage V2 between the positive electrode layer 10 and the reference electrode 110, and voltage V3 between the negative electrode layer 20 and the reference electrode 110. In this manner, electrical characteristics such as the voltage between at least one of the positive electrode layer 10 and the negative electrode layer 20 and the reference electrode 110 are measured. Furthermore, as the electrical characteristic, an electrical characteristic other than voltage, such as impedance, may be measured.

[0141] At this time, regardless of the operation of the positive electrode layer 10 and the negative electrode layer 20, the reference electrode 110 exhibits a constant value as an equilibrium potential between itself and the second solid electrolyte layer 130, and therefore the potential of the positive electrode layer 10 and / or the negative electrode layer 20 can be measured as the voltage difference between the reference electrode 110 and the positive electrode layer 10 and / or the negative electrode layer 20.

[0142] Furthermore, although the measurement of one power generating element section 50 has been described as an example here, it is also possible to simultaneously measure power generating element sections 50 each having a reference electrode section 170 formed thereon in the same manner.

[0143] [Effects, etc.] As disclosed in Non-Patent Document 1, various structures have been investigated for conventional solid-state batteries with reference electrodes, but the structures are complex and difficult to apply to practical batteries.

[0144] Furthermore, the solid-state battery having a reference electrode disclosed in Patent Document 1 has a structure in which a positive electrode, a solid electrolyte layer, and a negative electrode are stacked, and a third electrode is provided as a reference electrode in contact with the solid electrolyte layer or a solid electrolyte part provided so as to connect with the positive electrode, the solid electrolyte layer, and the negative electrode, with a width that matches the length of the side surfaces thereof, and it is possible to measure the potential of the positive electrode and / or the negative electrode.

[0145] However, when the solid electrolyte portion protrudes from the solid battery portion, as in the structure shown in Patent Document 1, the solid electrolyte portion is mechanically weak, and it is difficult to maintain the shape of the solid electrolyte portion and to measure the potential stably.

[0146] In this embodiment, in order to perform three-electrode measurement, the second solid electrolyte layer 130 in contact with the power generating element unit 50 is in electrochemical contact with the power generating element unit 50 so as not to come into contact with two or more power generating element units 50, and an insulating member 190 is arranged to surround the second solid electrolyte layer 130 of the reference electrode unit 170 formed on one power generating element unit 50. Therefore, for example, as shown in FIG. 1 , a battery 500 has a structure including a solid battery unit 100 in which a plurality of power generating element units 50 are electrically connected in series and stacked, a reference electrode unit 170, and a structure 200 having insulating members 190 arranged to sandwich the reference electrode unit 170 from both sides in the stacking direction. The insulating member 190 also covers the side surface 100a and is in contact with the side surface 100a.

[0147] With this configuration, the insulating member 190 can increase the mechanical strength of the reference electrode section 170. Furthermore, since the insulating member 190 surrounds the second solid electrolyte layer 130 and covers the side surface 100a, electrical and ionic short circuits between the reference electrode section 170 and the solid-state battery section 100 and between the plurality of power generating element sections 50 of the solid-state battery section 100 can be suppressed. This can improve the reliability of the battery 500. Furthermore, even when the reference electrode section 170 is housed in a thin exterior body such as a laminate film, the insulating member 190 helps maintain the shape of the reference electrode section 170, making it possible to stably measure the potential even in a battery 500 in which a plurality of power generating element sections 50 are stacked.

[0148] Furthermore, in a plan view of the second main surface 130b, the area of ​​the reference electrode 110 is smaller than the area of ​​the second main surface 130b, and the entire reference electrode 110 is located inside the second main surface 130b. This makes it difficult for the reference electrode 110 to come into contact with the solid-state battery unit 100. For example, even when pressure is applied to improve contact between the side surface 100a of the solid-state battery unit 100 and the second solid electrolyte layer 130, it is possible to make it difficult for a short circuit to occur between the reference electrode 110 and the solid-state battery unit 100.

[0149] Furthermore, by geometrically arranging the plurality of reference electrode parts 170 formed on the side surface 100a of the solid-state battery part 100 in a predetermined pattern and disposing the insulating member 190 between the plurality of second solid electrolyte layers 130, the plurality of reference electrode parts 170 are disposed in an appropriately dispersed manner, and it is possible to form many of the plurality of reference electrode parts 170 in a compact area while increasing the mechanical strength of the plurality of reference electrode parts 170.

[0150] The above configuration realizes a battery 500 that can maintain stable measurement of electrical characteristics such as the potential of the positive electrode layer 10 and the negative electrode layer 20 in at least one of the plurality of stacked power generating element units 50. Therefore, this embodiment makes it possible to measure the electrical characteristics of the electrodes, thereby realizing a highly reliable battery 500.

[0151] Since the potential of the positive electrode layer 10 and / or the negative electrode layer 20 alone can be measured using the battery 500 according to this embodiment, the electrical characteristics of the positive electrode layer 10 and / or the negative electrode layer 20 in a stacked battery can be grasped in the development of the battery, and the electrical characteristics of the positive electrode layer 10 and the negative electrode layer 20 can be measured separately, so that the development and design of the battery can be promoted effectively and efficiently.

[0152] Furthermore, when the battery 500 according to the present embodiment is applied to a practical battery, for example, the following effects can be achieved. In the positive electrode layer 10, for example, when the structure of the active material changes above a certain potential, resulting in a decrease in electrode performance, such as charge / discharge capacity and cycle characteristics, the potential of the positive electrode layer 10 can be monitored and controlled so as not to exceed that potential. As a result, in the battery 500, a decrease in electrode performance due to charging can be suppressed. In addition, in the negative electrode layer 20, for example, in the case of an electrode used up to a potential close to the metallic lithium deposition potential during charging, the deposition of metallic lithium can be suppressed by monitoring and controlling the potential so as not to reach the metallic lithium deposition potential (e.g., 0 V or less, vs. Li / Li). As a result, in the battery 500, the reduction in charge / discharge capacity and cycle deterioration that result in a shortened battery life, as well as the risk of short-circuiting, overheating, and fire that result from the deposition of metallic lithium, can be reduced.

[0153] [Variation 1] Next, a first modification of the embodiment will be described. In the following description of the modification, differences from the embodiment will be mainly described, and descriptions of commonalities will be omitted or simplified.

[0154] Fig. 5A is a side view showing a schematic configuration of a battery 501 according to this modified example. Fig. 5A is a plan view of the side surface 100a of the solid-state battery section 100. Fig. 5B is a side view showing the battery 501 shown in Fig. 5A with the reference electrode current collector 150 removed. Note that in Figs. 5A and 5B, a dotted pattern is applied to the insulating member 191 to make it easier to understand the region where the insulating member 191 is formed, but this is not intended to mean that the insulating member 191 actually has a dotted pattern.

[0155] As shown in FIG. 5A, battery 501 differs from battery 500 according to the embodiment in that it includes structure 201 instead of structure 200.

[0156] The structure 201 has the same configuration as the structure 200, except that the arrangement of the reference electrode section 170 is different from that of the structure 200. The structure 201 has an insulating member 191 in which a plurality of openings 191a are provided in an arrangement different from that of the insulating member 190. The insulating member 191 has the same configuration as the insulating member 190, except that the shape in a plan view is different from that of the insulating member 190.

[0157] 5B, the plurality of second solid electrolyte layers 130 are provided inside each of the plurality of openings 191a provided in the insulating member 191. The second solid electrolyte layers 130 are in contact with the regions of the side surface 100a exposed by the openings 191a.

[0158] The insulating member 191 completely surrounds each of the plurality of second solid electrolyte layers 130 in a plan view of the side surface 100a of the solid battery section 100. This more securely protects the reference electrode section 170. The insulating member 191 also contacts both end faces of the second solid electrolyte layer 130 in the stacking direction of the solid battery section 100.

[0159] An insulating member 191 is disposed between the plurality of second solid electrolyte layers 130. Furthermore, all of the plurality of second solid electrolyte layers 130 provided on the side surface 100a have portions that do not overlap with each other when viewed in the stacking direction of the solid-state battery unit 100. Therefore, for example, when viewed in the stacking direction of the solid-state battery unit 100, the plurality of second solid electrolyte layers 130 have portions that overlap only with the insulating member 191 of the structure 201. This simplifies the structure of the connection portion for electrical connection with each reference electrode unit 170, since even if a conductive member or the like is extended from each reference electrode unit 170 along the surface of the insulating member 191 in the stacking direction, the conductive member or the like does not collide with other reference electrode units 170. For example, by extending a conductive member or the like from each reference electrode unit 170 along the stacking direction, current can be extracted from the upper or lower end of the battery 501. In this case, the battery 501 can be mounted on a wiring board or the like to connect the conductive member or the like, allowing the electrical characteristics of each electrode layer to be easily measured.

[0160] The multiple second solid electrolyte layers 130 are arranged on the side surface 100a to form multiple rows L21, L22 extending in a direction not perpendicular to the stacking direction of the solid battery unit 100. The extending direction of the multiple rows L21, L22 is inclined with respect to the stacking direction. This allows the multiple second solid electrolyte layers 130 to be arranged so that each second solid electrolyte layer 130 has portions that do not overlap with each other when viewed from the stacking direction of the solid battery unit 100. Note that the multiple second solid electrolyte layers 130 may also be arranged along a single row extending in a direction inclined with respect to the stacking direction.

[0161] With the above configuration, even in the battery 501, which has a different arrangement of the plurality of reference electrode portions 170 from the battery 500, it is possible to measure the electrical characteristics of the electrode layer, thereby improving reliability.

[0162] [Variation 2] Next, a second modification of the embodiment will be described. In the following description of the modification, differences from the embodiment will be mainly described, and descriptions of commonalities will be omitted or simplified.

[0163] FIG. 6 is a cross-sectional view showing a schematic configuration of a battery 502 according to this modification.

[0164] As shown in FIG. 6, the battery 502 differs from the battery 500 according to the embodiment in that it includes a solid-state battery unit 102 instead of the solid-state battery unit 100.

[0165] In the solid-state battery section 102, a plurality of power generating element sections 50 are electrically connected in parallel and stacked. This makes it possible to realize a high-capacity battery 502. A side surface 102a of the solid-state battery section 102 contacts the structure 200.

[0166] Adjacent power generating element sections 50 are stacked with a positive electrode current collector 60 or a negative electrode current collector 70 interposed therebetween. The power generating element sections 50 are stacked so that the same electrode layers of adjacent power generating element sections 50 are electrically connected to each other via the current collectors.

[0167] The multiple power generating element units 50 are stacked such that the arrangement direction of each layer of adjacent power generating element units 50 is reversed. Therefore, in adjacent power generating element units 50, the respective positive electrode layers 10 or the respective negative electrode layers 20 face each other without the first solid electrolyte layer 30 interposed therebetween. Two positive electrode current collectors 60 are disposed between adjacent power generating element units 50 stacked such that the respective positive electrode layers 10 face each other without the first solid electrolyte layer 30 interposed therebetween. Furthermore, two negative electrode current collectors 70 are disposed between adjacent power generating element units 50 stacked such that the respective negative electrode layers 20 face each other without the first solid electrolyte layer 30 interposed therebetween. This electrically connects the same electrode layers of adjacent power generating element units 50. The number of positive electrode current collectors 60 and negative electrode current collectors 70 disposed between adjacent power generating element units 50 is not limited to two and may be one. That is, the positive electrode layers 10 may be laminated on both main surfaces of one positive electrode current collector 60, and the negative electrode layers 20 may be laminated on both main surfaces of one negative electrode current collector 70.

[0168] Furthermore, the positive electrode current collector 60, the negative electrode current collector 70, and the power generating element section 50 located between the positive electrode current collector 60 and the negative electrode current collector 70 constitute a unit battery cell 80. Therefore, the solid-state battery section 102 has a structure in which a plurality of unit battery cells 80 are stacked such that the same poles of adjacent unit battery cells 80 are connected to each other. As a result, the plurality of unit battery cells 80 are stacked while electrically connected in parallel.

[0169] As described above, in the battery 502, the structure 200 having the plurality of reference electrode units 170 is arranged so as to contact the side surface 102a of the solid-state battery unit 102 having the plurality of power generating element units 50 electrically connected in parallel and stacked. As a result, even when the plurality of power generating element units 50 are connected in parallel, the electrical characteristics of each electrode layer can be measured, as in the battery 500 according to the embodiment, thereby realizing a highly reliable battery 502. Furthermore, when the plurality of power generating element units 50 are connected in parallel and stacked, an ionic short circuit does not occur even if the second solid electrolyte layer 130 is in contact with two or more power generating element units 50. However, since the second solid electrolyte layer 130 is not in contact with two or more power generating element units 50, ionic conduction is stable when measuring the electrical characteristics of each power generating element unit 50, allowing the electrical characteristics to be measured with high accuracy.

[0170] [Variation 3] Next, a third modification of the embodiment will be described. In the following description of the modification, differences from the embodiment and the second modification of the embodiment will be mainly described, and descriptions of commonalities will be omitted or simplified.

[0171] FIG. 7 is a cross-sectional view showing a schematic configuration of a battery 503 according to this modification.

[0172] As shown in FIG. 7, battery 503 differs from battery 502 according to the second modification of the embodiment in that it includes structure 203 instead of structure 200.

[0173] The structure 203 has a plurality of reference electrode portions 173 and an insulating member 193 .

[0174] In the structure 203, two or more of the multiple reference electrode parts 173 include a common reference electrode 113 and a common reference electrode current collector 153. That is, the reference electrodes 113 and the reference electrode current collectors 153 in two or more of the multiple reference electrode parts 173 are connected to each other. The reference electrodes 113 and the reference electrode current collectors 153 in all of the multiple reference electrode parts 173 may be connected to each other.

[0175] The reference electrode 113 is in contact with the second solid electrolyte layers 130 of two or more of the multiple reference electrode portions 173. The reference electrode 113 has, for example, a region facing the side surface 102a of the solid battery portion 102 with the second solid electrolyte layer 130 interposed therebetween, and a region facing the side surface 102a with the insulating member 193 interposed therebetween.

[0176] The reference electrode current collector 153 is in contact with the reference electrode 113. The reference electrode current collector 153 covers, for example, the entire surface of the reference electrode 113 opposite to the second solid electrolyte layer 130 side.

[0177] In this way, by connecting the reference electrodes 113 and the reference electrode collectors 153 in two or more of the multiple reference electrode portions 173, the structure of the structure 203 can be simplified and the mechanical strength of the structure 203 can be increased.

[0178] Note that either the reference electrode 113 or the reference electrode current collector 153 may not be connected, and like the above-mentioned reference electrode 110 or reference electrode current collector 150, the one may be provided individually for each reference electrode portion 173.

[0179] [Variation 4] Next, a fourth modification of the embodiment will be described. In the following description of the fourth modification, differences from the embodiment will be mainly described, and descriptions of commonalities will be omitted or simplified.

[0180] FIG. 8 is a cross-sectional view showing a schematic configuration of a battery 504 according to this modification.

[0181] As shown in FIG. 8, the battery 504 differs from the battery 500 according to the embodiment in that it includes a structure 204 instead of the structure 200 .

[0182] The structure 204 has a plurality of reference electrode portions 170 and an insulating member 194. The structure 204 has the same configuration as the structure 200, except that the width of the solid-state battery portion 100 in the stacking direction is smaller than that of the structure 200.

[0183] In a plan view of the side surface 100a of the solid-state battery unit 100, the structure 204 does not extend beyond both ends of the solid-state battery unit 100 in the stacking direction of the solid-state battery unit 100. Furthermore, the length of the structure 204 in the stacking direction of the solid-state battery unit 100 is shorter than the length of the solid-state battery unit 100 in the stacking direction of the solid-state battery unit 100. In other words, in a plan view of the side surface 100a of the solid-state battery unit 100, the structure 204 is entirely located inside both ends of the solid-state battery unit 100 in the stacking direction. In this modification, in a plan view of the side surface 100a, the outermost periphery of the structure 204 is made up of the insulating member 194, and the insulating member 194 is entirely located inside both ends of the solid-state battery unit 100 in the stacking direction. As a result, even when the solid-state battery unit 100 is used while being pressurized in the stacking direction, the structure 204 is less likely to interfere with the pressure applied to the solid-state battery unit 100, thereby improving the reliability of the battery 504. Furthermore, even if the solid-state battery unit 100 is compressed in the stacking direction when pressure is applied to the solid-state battery unit 100 from the stacking direction, the structure 204 is located inside the solid-state battery unit 100 in the stacking direction of the solid-state battery unit 100, so the compression of the solid-state battery unit 100 is less likely to be hindered, and the battery characteristics of the solid-state battery unit 100 can be improved.

[0184] (Other embodiments) While the battery according to the present disclosure has been described above based on the embodiments and modifications, the present disclosure is not limited to these embodiments and modifications. As long as they do not deviate from the gist of the present disclosure, various modifications that would occur to a person skilled in the art to the embodiments and modifications, and other forms constructed by combining some of the components of the embodiments and modifications, are also included in the scope of the present disclosure.

[0185] For example, in the above-described embodiments and modifications, the structures 200, 201, and 204 have a plurality of reference electrode sections 170, but this is not limitative. The number of reference electrode sections 170 that the structures 200, 201, and 204 have may be one.

[0186] Furthermore, for example, the features of the structures in the above-described modified examples may be combined. For example, in batteries 502 to 504, the arrangement of the second solid electrolyte layer 130 may be the same as that of battery 501. Furthermore, for example, in batteries 501 to 503, the structures may be located inside both ends of the solid battery section 100 in the stacking direction.

[0187] Furthermore, for example, in the solid-state battery section, a plurality of power generating element sections 50 may be connected in a combination of series connection and parallel connection.

[0188] Furthermore, the above-described embodiments and modifications can be subject to various changes, substitutions, additions, omissions, and the like within the scope of the claims or their equivalents. [Industrial Applicability]

[0189] The battery according to the present disclosure can be used for monitoring, designing, or developing electrodes, etc. Furthermore, the battery according to the present disclosure can be used in electronic devices, electric appliances, electric vehicles, etc. as a battery capable of measuring the electrical properties of electrodes. [Explanation of symbols]

[0190] 10 Positive electrode layer 20 negative electrode layer 30 First solid electrolyte layer 50 Power generation element 60 Positive electrode current collector 70 Negative electrode current collector 91, 92, 93 Voltage measuring instruments 100, 102 Solid state battery section 100a, 102a side 110, 113 Reference electrode 130 Second solid electrolyte layer 130a First principal surface 130b Second principal surface 150, 153 Reference electrode current collector 170, 173 Reference electrode 190, 191, 193, 194 Insulating members 200, 201, 203, 204 structure 500, 501, 502, 503, 504 batteries

Claims

1. a solid-state battery section having a structure in which a plurality of power generating element sections are stacked, each of which has a first electrode layer, a second electrode layer, and a first solid electrolyte layer located between the first electrode layer and the second electrode layer; a second solid electrolyte layer that contacts a power generation element portion on a side surface of the solid battery portion without contacting two or more of the plurality of power generation element portions; at least one reference electrode portion that faces the side surface of the solid battery portion across the second solid electrolyte layer and includes a reference electrode that contacts the second solid electrolyte layer; and a structure that has an insulating member that is arranged to surround the second solid electrolyte layer in a plan view of the side surface of the solid battery portion and covers the side surface of the solid battery portion, the at least one reference electrode portion is a plurality of reference electrode portions, the second solid electrolyte layers included in the plurality of reference electrode portions are each in contact with a different one of the plurality of power generating element portions, the insulating member is disposed so as to surround each of the plurality of second solid electrolyte layers in a plan view with respect to a side surface of the solid state battery portion, the plurality of second solid electrolyte layers include two second solid electrolyte layers in contact with adjacent power generating element units among the plurality of power generating element units, the two second solid electrolyte layers do not overlap when viewed from the stacking direction of the solid battery portion; battery.

2. the insulating members arranged to surround each of the plurality of second solid electrolyte layers are connected to each other; The battery of claim 1 .

3. the plurality of second solid electrolyte layers each have a portion that does not overlap with one another when viewed along the stacking direction of the solid battery portion; The battery according to claim 1 or 2.

4. the number of the plurality of second solid electrolyte layers is four or more; the plurality of second solid electrolyte layers are arranged on the side surface of the solid battery section so as to form a plurality of rows extending along a direction not orthogonal to the stacking direction of the solid battery section. The battery according to any one of claims 1 to 3.

5. The plurality of power generating element units are electrically connected in series and stacked. The battery of any one of claims 1 to 4.

6. The plurality of power generating element units are electrically connected in parallel and stacked. The battery of any one of claims 1 to 4.

7. A solid-state battery section having a structure in which a plurality of power generating element sections are stacked, each of which has a first electrode layer, a second electrode layer, and a first solid electrolyte layer located between the first electrode layer and the second electrode layer; a second solid electrolyte layer that contacts a power generation element portion on a side surface of the solid battery portion without contacting two or more of the plurality of power generation element portions; at least one reference electrode portion that faces the side surface of the solid battery portion across the second solid electrolyte layer and includes a reference electrode that contacts the second solid electrolyte layer; and a structure that has an insulating member that is arranged to surround the second solid electrolyte layer in a plan view of the side surface of the solid battery portion and covers the side surface of the solid battery portion, the at least one reference electrode portion is a plurality of reference electrode portions, the second solid electrolyte layers included in the plurality of reference electrode portions are each in contact with a different one of the plurality of power generating element portions, the insulating member is disposed so as to surround each of the plurality of second solid electrolyte layers in a plan view with respect to a side surface of the solid state battery portion, the plurality of power generating element units are electrically connected in parallel and stacked, the reference electrodes in two or more of the plurality of reference electrode units are connected to each other; battery.

8. A solid-state battery unit having a structure in which a plurality of power generating element units are stacked, each of which has a first electrode layer, a second electrode layer, and a first solid electrolyte layer located between the first electrode layer and the second electrode layer; a second solid electrolyte layer that contacts a power generation element portion on a side surface of the solid battery portion without contacting two or more of the plurality of power generation element portions; at least one reference electrode portion that faces the side surface of the solid battery portion across the second solid electrolyte layer and includes a reference electrode that contacts the second solid electrolyte layer; and a structure that has an insulating member that is arranged to surround the second solid electrolyte layer in a plan view of the side surface of the solid battery portion and covers the side surface of the solid battery portion, the at least one reference electrode portion is a plurality of reference electrode portions, the second solid electrolyte layers included in the plurality of reference electrode portions are each in contact with a different one of the plurality of power generating element portions, the insulating member is disposed so as to surround each of the plurality of second solid electrolyte layers in a plan view with respect to a side surface of the solid state battery portion, the plurality of power generating element units are electrically connected in parallel and stacked, each of the plurality of reference electrode parts further includes a reference electrode current collector in contact with the reference electrode; At least one of the reference electrodes in two or more of the plurality of reference electrode parts and the reference electrode current collectors in the two or more reference electrode parts are connected to each other. battery.

9. The insulating member includes an insulating resin. The battery of any one of claims 1 to 8.

10. In a plan view of a side surface of the solid-state battery unit, the structure does not extend beyond both ends of the solid-state battery unit in a stacking direction of the solid-state battery unit.

10. The battery of claim 1.

11. a length of the structure in a stacking direction of the solid-state battery unit is smaller than a length of the solid-state battery unit in the stacking direction of the solid-state battery unit; The battery of claim 10.

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