All-solid-state batteries

Abstract

To provide an all-solid-state battery capable of achieving enlargement of an electrode area and an increase in space factor of an electrode in a laminated pouch cell.SOLUTION: An all-solid-state battery 1 includes a stacked electrode body 10 and an exterior film 20 that accommodates the stacked electrode body 10. The stacked electrode body 10 includes at least a first electrode stacked body 30 stacked such that both stacked end outermost surfaces become a negative electrode current collector layer 71, and a second electrode stacked body 40 stacked such that both stacked end outermost surfaces become a positive electrode current collector layer 61. A first negative electrode bundled body 100 of the negative electrode current collector layer 71 of the first electrode stacked body 30 and a first positive electrode bundled body 130 of the positive electrode current collector layer 61 of the second electrode stacked body 40 are connected in series. The exterior film 20 has an inner resin layer 21, a metal layer 22, and an outer resin layer 23, and a first internal connecting portion 210 that electrically connects the first negative electrode bundled body 100 and the first positive electrode bundled body 130 to the metal layer 22 is provided at one end portion of the stacked electrode body 10 in a width direction to which the first negative electrode bundled body 100 and the first positive electrode bundled body 130 are connected in series.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an all-solid-state battery. [Background technology]

[0002] In recent years, research and development into all-solid-state batteries has been underway to contribute to energy efficiency, ensuring that more people have access to affordable, reliable, sustainable and advanced energy.

[0003] Large-capacity laminate pouch cells for electric vehicles and other applications generally have electrode tabs on both longitudinal ends. Therefore, when stacking and connecting battery cells in series or parallel, space is required on both longitudinal ends of the battery cells to accommodate bus bars or other devices that connect the battery cell terminals. This space does not allow the electrodes in the battery cells to extend longitudinally.

[0004] To monitor the voltage of all battery cells, wiring for the CVS (Computer-Controlled Vehicle System) must be taken out from the positive and negative terminals of all cells. As a result, part of the CVS wiring must necessarily run vertically through the module, and space must be secured for this. This reduces the volume that can be occupied by the stacked cells, which in turn reduces the battery capacity.

[0005] A known technique for increasing the volume that can be occupied by a laminated cell is to shorten the protruding length of the tab lead by hollowing out the inner resin layer that constitutes the laminate film and connecting it to the power generating element (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-28023 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the technology related to all-solid-state batteries, there are problems in that the electrode area cannot be increased inside a laminate pouch cell, and there are also problems in that the electrode space factor cannot be increased inside a laminate pouch cell.

[0008] In order to solve the above problems, the present invention aims to expand the electrode area and increase the electrode space factor inside a laminate pouch cell, thereby contributing to improved energy efficiency. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention provides the following means. [1] An electrode laminate and an exterior film that houses the electrode laminate, the electrode laminate has at least a first electrode laminate laminated so that both outermost surfaces of the laminate are negative electrode current collector layers, and a second electrode laminate laminated so that both outermost surfaces of the laminate are positive electrode current collector layers, a negative electrode convergence body of a negative electrode current collector layer of the first electrode stack and a positive electrode convergence body of a positive electrode current collector layer of the second electrode stack are connected in series, The exterior film has an inner resin layer, a metal layer, and an outer resin layer, an internal connection portion that electrically connects the negative electrode convergent and the positive electrode convergent to the metal layer is provided at one end in the width direction of the electrode stack, where the negative electrode convergent and the positive electrode convergent are connected in series.

[0010] The negative electrode convergent of the negative electrode current collector layer of the first electrode laminate and the positive electrode convergent of the positive electrode current collector layer of the second electrode laminate are connected in series, and the negative electrode convergent and positive electrode convergent are connected in series. At one end in the width direction of the electrode laminate, an internal connection section is provided that electrically connects the negative electrode convergent and positive electrode convergent with the metal layer of the exterior film. This makes it possible to expand the electrode area of ​​the electrode laminate inside the exterior film and increase the electrode space factor of the electrode laminate.

[0011] [2] At the other end in the width direction of the electrode laminate, a positive electrode convergence body of a positive electrode current collector layer of the first electrode laminate and a negative electrode convergence body of a negative electrode current collector layer of the second electrode laminate are each joined to a tab lead, and The all-solid-state battery according to [1], wherein the exterior film has an exposed portion at the other end in the width direction of the electrode laminate where the metal layer is exposed and which is electrically connected to an electrical device outside the all-solid-state battery.

[0012] At the other end in the width direction of the electrode laminate, the positive electrode convergent of the positive electrode current collector layer of the first electrode laminate and the negative electrode convergent of the negative electrode current collector layer of the second electrode laminate are each joined to a tab lead, and at the other end in the width direction of the electrode laminate, the exterior film has an exposed portion where the metal layer is exposed and which is electrically connected to an electrical device outside the all-solid-state battery, making it possible to extract the electric potential within the all-solid-state battery. [Effects of the Invention]

[0013] According to the present invention, it is possible to increase the electrode area in the electrode stack inside the laminate pouch cell, and also to increase the electrode space factor in the electrode stack. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a cross-sectional view illustrating an example of an all-solid-state battery according to an embodiment of the present invention. [Figure 2] FIG. 2 is a plan view showing an example of the structure of a first electrode laminate constituting an all-solid-state battery according to an embodiment of the present invention. [Figure 3] FIG. 2 is a plan view showing an example of the structure of a second electrode laminate constituting an all-solid-state battery according to an embodiment of the present invention. [Figure 4] FIG. 1 is a plan view showing an example of the structure of an electrode stack constituting an all-solid-state battery according to an embodiment of the present invention. [Figure 5] 10 is a schematic diagram illustrating that the potential at the connection midpoint between the first electrode stack and the second electrode stack is equal to the potential at both ends of the stack of the first electrode stack and the second electrode stack. FIG. [Figure 6] 10 is a schematic diagram illustrating that the potential at the connection midpoint between the first electrode stack and the second electrode stack is equal to the potential at both ends of the stack of the first electrode stack and the second electrode stack. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0016] [Structure of all-solid-state batteries] FIG. 1 is a cross-sectional view showing an example of an all-solid-state battery according to an embodiment of the present invention. FIG. 2 is a plan view showing an example of the structure of a first electrode laminate constituting an all-solid-state battery according to an embodiment of the present invention. FIG. 3 is a plan view showing an example of the structure of a second electrode laminate constituting an all-solid-state battery according to an embodiment of the present invention. FIG. 4 is a plan view showing an example of the structure of an electrode laminate constituting an all-solid-state battery according to an embodiment of the present invention. Note that the drawings used in the following description may conveniently show characteristic portions in an enlarged manner to make the characteristics easier to understand, and the dimensional ratios of the respective components are not limited to those shown.

[0017] The all-solid-state battery 1 includes an electrode laminate 10 and an exterior film 20 that houses the electrode laminate 10. The electrode laminate 10 has a first electrode laminate 30 and a second electrode laminate 40.

[0018] The first electrode stack 30 and the second electrode stack 40 each have a plurality of single-layer sheet electrodes 50. In Fig. 1, the first electrode stack 30 and the second electrode stack 40 each have six single-layer sheet electrodes 50 (a first single-layer sheet electrode 50A, a second single-layer sheet electrode 50B, a third single-layer sheet electrode 50C, a fourth single-layer sheet electrode 50D, a fifth single-layer sheet electrode 50E, and a sixth single-layer sheet electrode 50F). The single-layer sheet electrode 50 includes a positive electrode 60, a negative electrode 70, and a solid electrolyte layer 80 disposed between the positive electrode 60 and the negative electrode 70 and including a solid electrolyte. The positive electrode 60 is formed by laminating a positive electrode current collector layer 61 and a positive electrode active material layer 62 containing at least a solid electrolyte. The negative electrode 70 is formed by laminating a negative electrode current collector layer 71 and a negative electrode active material layer 72 containing at least a solid electrolyte.

[0019] The first electrode laminate 30 has a plurality of single-layer sheet electrodes 50 stacked such that the outermost surfaces at both ends of the laminate are negative electrode current collector layers 71. Specifically, in the first electrode laminate 30, the negative electrode current collector layer 71 of the first single-layer sheet electrode 50A forms one outermost surface in the stacking direction (the upper surface side of the first electrode laminate in FIG. 1 ). The negative electrode current collector layer 71 of the sixth single-layer sheet electrode 5F forms the other outermost surface in the stacking direction (the lower surface side of the first electrode laminate in FIG. 1 ).

[0020] The second electrode laminate 40 has a plurality of single-layer sheet electrodes 50 stacked on top of each other such that the outermost surfaces at both ends of the laminate are positive electrode current collector layers 61. Specifically, in the second electrode laminate 40, the positive electrode current collector layer 61 of the first single-layer sheet electrode 50A forms one outermost surface in the stacking direction (the upper surface side of the second electrode laminate in FIG. 1 ). The positive electrode current collector layer 61 of the sixth single-layer sheet electrode 5F forms the other outermost surface in the stacking direction (the lower surface side of the second electrode laminate in FIG. 1 ).

[0021] At one end in the width direction of the electrode laminate 10, a first tab lead 90 is joined to the negative electrode current collector layer 71 of the first electrode laminate 30. The first tab leads 90 are converged to form a first negative electrode convergence body 100. A first clad material 110 is joined to the first negative electrode convergence body 100. At one end in the width direction of the electrode laminate 10, a second tab lead 120 is joined to the positive electrode current collector layer 61 of the second electrode laminate 40. The second tab leads 120 are converged to form a first positive electrode convergence body 130. A second clad material 140 is joined to the first positive electrode convergence body 130. By joining the first clad material 110 and the second clad material 140, the first negative electrode convergence body 100 and the first positive electrode convergence body 130 are connected in series.

[0022] At the other end in the width direction of the electrode laminate 10, a third tab lead 150 is joined to the positive electrode current collector layer 61 of the first electrode laminate 30. The third tab lead 150 is converged to form a second positive electrode convergence body 160. A fourth tab lead 170 is joined to the second positive electrode convergence body 160. At the other end in the width direction of the electrode laminate 10, a fifth tab lead 180 is joined to the negative electrode current collector layer 71 of the second electrode laminate 40. The fifth tab lead 180 is converged to form a second negative electrode convergence body 190. A sixth tab lead 200 is joined to the second negative electrode convergence body 190. The fourth tab lead 170 is a positive electrode terminal where the first electrode stack 30 and the second electrode stack 40 are connected in series, and the sixth tab lead 200 is a positive electrode terminal where the first electrode stack 30 and the second electrode stack 40 are connected in series.

[0023] The exterior film 20 has an inner resin layer 21 , a metal layer 22 , and an outer resin layer 23 .

[0024] At one end in the width direction of the first electrode stack 30 and the second electrode stack 40, where the first negative electrode convergence body 100 and the first positive electrode convergence body 130 are connected in series, a first internal connection portion 210 is provided, which electrically connects the first negative electrode convergence body 100 and the first positive electrode convergence body 130 to the metal layer 22 of the exterior film 20.

[0025] At the other end in the width direction of the first electrode stack 30 and the second electrode stack 40, where the first negative electrode convergence body 100 and the first positive electrode convergence body 130 are connected in series, a CVS wiring terminal portion 230 is provided that connects to the metal layer 22 of the exterior film 20.

[0026] The fourth tab lead 170 is connected to the CVS 400 via wiring 310. The sixth tab lead 200 is connected to the CVS 400 via wiring 320. The CVS wiring terminal portion 230 is connected to the CVS 400 via wiring 330. At the other end in the width direction of the electrode stack 10, the exterior film 20 has an exposed portion where the metal layer 22 is exposed and is electrically connected to an electrical device (such as the CVS 400) external to the all-solid-state battery 1. The metal layer 22 of the exterior film 20 and the CVS wiring terminal portion 230 are connected at the exposed portion.

[0027] (positive electrode) The positive electrode 60 is formed by laminating a positive electrode current collector layer 61 and a positive electrode active material layer 62 containing at least a solid electrolyte. In this embodiment, the positive electrode 60 has the positive electrode current collector layer 61 and the positive electrode active material layer 62 formed on one main surface of the positive electrode current collector layer 61 and containing a positive electrode active material and a solid electrolyte.

[0028] The positive electrode current collector layer 61 is preferably made of at least one material with high electrical conductivity. Examples of highly conductive materials include metals or alloys containing at least one of silver (Ag), palladium (Pd), gold (Au), platinum (Pt), aluminum (Al), copper (Cu), chromium (Cr), and nickel (Ni), as well as non-metals such as carbon (C). Considering not only high conductivity but also manufacturing costs, aluminum, nickel, or stainless steel is preferred. Furthermore, aluminum is less likely to react with the positive electrode active material, negative electrode active material, and solid electrolyte. Therefore, using aluminum for the positive electrode current collector layer 61 can reduce the internal resistance of the all-solid-state battery.

[0029] Examples of the shape of the positive electrode current collector layer 61 include foil, plate, mesh, nonwoven fabric, and foam. In order to improve adhesion to the positive electrode active material layer 62, carbon or the like may be disposed on the surface of the positive electrode current collector layer 61, or the surface may be roughened.

[0030] The positive electrode active material layer 62 contains a positive electrode active material that donates and receives lithium ions and electrons. The positive electrode active material is not particularly limited as long as it is a material that can reversibly release and absorb lithium ions and transport electrons, and known positive electrode active materials that can be used in the positive electrode of all-solid-state lithium-ion batteries can be used. For example, lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium manganese oxide (LiMn2O4), solid solution oxide (Li2MnO3-LiMO2 (M=Co, Ni, etc.)), lithium-manganese-nickel-cobalt oxide (LiNi x Mn y Co z O2, x+y+z=1), composite oxides such as olivine-type lithium phosphate (LiFePO4); conductive polymers such as polyaniline and polypyrrole; sulfides such as Li2S, CuS, Li-Cu-S compounds, TiS2, FeS, MoS2, and Li-Mo-S compounds; mixtures of sulfur and carbon; etc. The positive electrode active material may be composed of one kind of the above materials alone, or may be composed of two or more kinds.

[0031] The positive electrode active material layer 62 includes a solid electrolyte that transfers lithium ions to and from the positive electrode active material. The solid electrolyte is not particularly limited as long as it has lithium ion conductivity, and materials typically used in all-solid-state lithium ion batteries can be used. Examples include inorganic solid electrolytes such as sulfide solid electrolyte materials, oxide solid electrolyte materials, halide solid electrolytes, and lithium-containing salts, polymer-based solid electrolytes such as polyethylene oxide, and gel-based solid electrolytes containing lithium-containing salts and lithium-ion conductive ionic liquids. Among these, sulfide solid electrolyte materials are preferred from the standpoints of high lithium ion conductivity, structural formability by pressing, and interfacial bonding. The solid electrolyte may be composed of one kind of the above materials alone or two or more kinds of them. The solid electrolyte contained in the positive electrode active material layer 62 may be the same material as the solid electrolyte contained in the negative electrode active material layer 72 and the solid electrolyte layer 80, or may be a different material.

[0032] The positive electrode active material layer 62 may contain a conductive additive from the viewpoint of improving the conductivity of the positive electrode 60. The conductive additive may be any conductive additive that is generally usable in all-solid-state lithium-ion batteries. Examples of the conductive additive include carbon black such as acetylene black and Ketjen black; carbon fiber; vapor-grown carbon fiber; graphite powder; and carbon materials such as carbon nanotubes. The conductive additive may be composed of one or more of the above materials.

[0033] The positive electrode active material layer 62 may also contain a binder that functions to bind the positive electrode active materials together and between the positive electrode active material and the positive electrode current collector layer 61 .

[0034] In this embodiment, the positive electrode active material layer 62 is formed on one main surface of the positive electrode current collector layer 61, but is not limited thereto, and the positive electrode active material layer 62 may be formed on both main surfaces of the positive electrode current collector layer 61. Furthermore, when the positive electrode active material layer 62 has a three-dimensional porous structure such as a mesh, nonwoven fabric, or foam, the positive electrode active material layer 62 may be provided integrally with the positive electrode current collector layer 61.

[0035] In the first electrode laminate 30, the positive electrode current collector layers 61 are assembled at one end in the width direction of the all-solid-state battery 1. In the second electrode laminate 40, the positive electrode current collector layers 61 are assembled at the other end in the width direction of the all-solid-state battery 1.

[0036] (Negative electrode) The negative electrode 70 is formed by laminating a negative electrode current collector layer 71 and a negative electrode active material layer 72 containing at least a solid electrolyte. In this embodiment, the negative electrode 70 has the negative electrode current collector layer 71 and the negative electrode active material layer 72 that is formed on one main surface of the negative electrode current collector layer 71 and contains a negative electrode active material and a solid electrolyte.

[0037] Like the positive electrode current collector layer 61, the negative electrode current collector layer 71 is preferably made of at least one material with high conductivity. Examples of highly conductive materials include metals or alloys containing at least one of silver (Ag), palladium (Pd), gold (Au), platinum (Pt), aluminum (Al), copper (Cu), chromium (Cr), and nickel (Ni), or non-metals such as carbon (C). Considering manufacturing costs in addition to high conductivity, copper, nickel, or stainless steel is preferred. Furthermore, stainless steel is less likely to react with the positive electrode active material, the negative electrode active material, and the solid electrolyte. Therefore, using stainless steel for the negative electrode current collector layer 71 can reduce the internal resistance of the all-solid-state battery.

[0038] Examples of the shape of the negative electrode current collector layer 71 include foil, plate, mesh, nonwoven fabric, foam, etc. In order to improve adhesion to the negative electrode active material layer 72, carbon or the like may be disposed on the surface of the negative electrode current collector layer 71, or the surface may be roughened.

[0039] The negative electrode active material layer 72 contains a negative electrode active material that donates and receives lithium ions and electrons. The negative electrode active material is not particularly limited as long as it is a material that can reversibly absorb and release lithium ions and transport electrons, and known negative electrode active materials that can be used for the negative electrode of an all-solid-state lithium-ion battery can be used. Examples of such materials include carbonaceous materials such as natural graphite, artificial graphite, resin carbon, carbon fiber, activated carbon, hard carbon, and soft carbon; alloy-based materials mainly composed of tin, tin alloys, silicon, silicon alloys, gallium, gallium alloys, indium, indium alloys, aluminum, and aluminum alloys; conductive polymers such as polyacene, polyacetylene, and polypyrrole; metallic lithium; lithium titanium composite oxides (e.g., Li4Ti5O 12 These negative electrode active materials may be composed of one kind of the above materials alone, or two or more kinds of them.

[0040] The negative electrode active material layer 72 includes a solid electrolyte that transfers lithium ions to and from the negative electrode active material. There are no particular limitations on the solid electrolyte as long as it has lithium ion conductivity, and materials typically used in all-solid-state lithium ion batteries can be used. Examples of the solid electrolyte include inorganic solid electrolytes such as sulfide solid electrolyte materials, oxide solid electrolyte materials, halide solid electrolytes, and lithium-containing salts, polymer-based solid electrolytes such as polyethylene oxide, and gel-based solid electrolytes containing lithium-containing salts or lithium-ion conductive ionic liquids. The solid electrolyte may be composed of one or more of the above materials. The solid electrolyte contained in the negative electrode active material layer 72 may be the same as or different from the solid electrolyte contained in the positive electrode active material layer 62 or the solid electrolyte layer 80 .

[0041] The negative electrode active material layer 72 may contain a conductive additive, a binder, etc. There are no particular limitations on the materials used for these, and for example, the same materials as those used for the positive electrode active material layer 62 described above can be used.

[0042] In this embodiment, the negative electrode active material layer 72 is formed on one main surface of the negative electrode current collector layer 71, but is not limited thereto, and the negative electrode active material layer 72 may be formed on both main surfaces of the negative electrode current collector layer 71. Furthermore, when the negative electrode active material layer 72 has a three-dimensional porous structure such as a mesh, nonwoven fabric, or foam, the negative electrode active material layer 72 may be provided integrally with the negative electrode current collector layer 71.

[0043] In the first electrode laminate 30, the negative electrode current collector layers 71 are assembled at the other end in the width direction of the all-solid-state battery 1. In the second electrode laminate 40, the negative electrode current collector layers 71 are assembled at one end in the width direction of the all-solid-state battery 1.

[0044] (solid electrolyte layer) The solid electrolyte layer 80 is disposed between the positive electrode active material layer 62 and the negative electrode active material layer 72 .

[0045] The solid electrolyte is not particularly limited as long as it has lithium ion conductivity and insulating properties, and materials generally used in all-solid-state lithium ion batteries can be used. Examples include inorganic solid electrolytes such as sulfide solid electrolyte materials, oxide solid electrolyte materials, halide solid electrolytes, and lithium-containing salts, polymer-based solid electrolytes such as polyethylene oxide, and gel-based solid electrolytes containing lithium-containing salts and lithium ion-conductive ionic liquids. Among these, sulfide solid electrolyte materials are preferred from the viewpoints of high lithium ion conductivity, structural formability by pressing, and interfacial bonding. The form of the solid electrolyte material is not particularly limited, but may be, for example, in the form of particles.

[0046] The solid electrolyte layer 80 may contain an adhesive to impart mechanical strength and flexibility.

[0047] The solid electrolyte layer 80 may be in the form of a sheet having a porous substrate and a solid electrolyte held in the porous substrate. The form of the porous substrate is not particularly limited, and examples thereof include woven fabric, nonwoven fabric, mesh cloth, porous membrane, expanded sheet, and punched sheet. Of these forms, nonwoven fabric is preferred from the viewpoint of handleability, which allows for a greater loading amount of solid electrolyte.

[0048] The porous substrate is preferably made of an insulating material, which can improve the insulating properties of the solid electrolyte layer 80. Examples of insulating materials include resin materials such as nylon, polyester, polyethylene, polypropylene, polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polyvinylidene chloride, polyvinyl chloride, polyurethane, vinylon, polybenzimidazole, polyimide, polyphenylene sulfite, polyether ether ketone, cellulose, and acrylic resin; natural fibers such as hemp, wood pulp, and cotton linter; and glass.

[0049] (exterior film) The exterior film 20 is a laminated film having an inner resin layer 21, a metal layer 22, and an outer resin layer 23. Examples of resins that make up the inner resin layer 21 and the outer resin layer 23 include polyester resins such as polyethylene terephthalate (PET). The metal layer 22 is made of, for example, aluminum foil.

[0050] As described above, according to this embodiment, the first negative electrode convergence body 100 of the negative electrode current collector layer 71 of the first electrode laminate 30 and the first positive electrode convergence body 130 of the positive electrode current collector layer 61 of the second electrode laminate 40 are connected in series, and the first negative electrode convergence body 100 and the first positive electrode convergence body 130 are connected in series. The first internal connection portion 210 electrically connects the first negative electrode convergence body 100 and the first positive electrode convergence body 130 to the metal layer 22 of the exterior film 20 at one end in the width direction of the electrode laminate 10, thereby expanding the internal space of the exterior film 20. Therefore, the electrode area of ​​the electrode laminate 10 can be expanded inside the exterior film 20, and the electrode space factor of the electrode laminate 10 can be increased. This allows the energy density of the all-solid-state battery 1 to be increased, thereby increasing the amount of power that can be installed.

[0051] Furthermore, according to the present embodiment, at the other end in the width direction of the electrode laminate 10, the second positive electrode convergence body 160 of the positive electrode current collector layer 61 of the first electrode laminate 30 is joined to the third tab lead 150, and the sixth tab lead 200 is joined to the second negative electrode convergence body 190 of the negative electrode current collector layer 71 of the second electrode laminate 40, and at the other end in the width direction of the electrode laminate 10, the exterior film 20 has an exposed portion where the metal layer 22 is exposed and which is electrically connected to an electrical device external to the all-solid-state battery 1. Therefore, the potential inside the all-solid-state battery 1 can be extracted.

[0052] Furthermore, according to this embodiment, the first electrode laminate 30 and the second electrode laminate 40 are connected in series inside the exterior film 20, and therefore an insulating sheet or the like is not required between the first electrode laminate 30 and the second electrode laminate 40, and therefore it is possible to prevent a decrease in the electrode space factor of the electrode laminate 10 inside the exterior film 20. Therefore, it is possible to reduce manufacturing costs and improve the energy density of the all-solid-state battery 1.

[0053] Furthermore, according to this embodiment, the first electrode stack 30 and the second electrode stack 40 are connected in series inside the exterior film 20, and the potential at the connection midpoint (first internal connection portion 210) between the first electrode stack 30 and the second electrode stack 40 is extracted, so that the voltages of the first electrode stack 30 and the second electrode stack 40 can be monitored.

[0054] Furthermore, according to this embodiment, the potential of the connection midpoint (first internal connection portion 210) between the first electrode laminate 30 and the second electrode laminate 40 is equal to the potential at both ends of the first electrode laminate 30 and the second electrode laminate 40. Therefore, even if the inner resin layer 21 of the packaging film 20 is damaged and the electrode laminate 10 comes into contact with the metal layer 22, problems such as a short circuit can be prevented from occurring. This is because, if the potential of the connection midpoint between the first electrode laminate 30 and the second electrode laminate 40 is equal to the potential at both ends of the first electrode laminate 30 and the second electrode laminate 40, the potential of the outermost surface of the packaging film 20 of the second electrode laminate 40 and the packaging film 20 are equal, and therefore no short circuit occurs.

[0055] Here, using Figures 5 and 6, it will be explained that the potential at the connection midpoint between the first electrode stack 30 and the second electrode stack 40 is equal to the potential at both ends of the stack of the first electrode stack 30 and the second electrode stack 40. When the potential of the entire all-solid-state battery 1 is 7.4 V, the potential at the connection midpoint between the first electrode stack 30 and the second electrode stack 40 is 3.7 V. The potential at both ends of the stack of the first electrode stack 30 and the second electrode stack 40 is also 3.7 V. Therefore, the potential at the connection midpoint between the first electrode stack 30 and the second electrode stack 40 and the potential at both ends of the stack of the first electrode stack 30 and the second electrode stack 40 are equal.

[0056] Furthermore, if the potential at the connection midpoint of the first electrode stack 30 and the second electrode stack 40 is equal to the potential at both ends of the stack of the first electrode stack 30 and the second electrode stack 40, then it is possible to monitor the potential of the entire all-solid-state battery 1, for example, by monitoring the voltage between the reference (0 V) and the connection midpoint (3.7 V) and the voltage between the connection midpoint (3.7 V) and the highest point (7.4 V).

[0057] Furthermore, according to this embodiment, the metal layer 22 of the exterior film 20 is used as part of the wiring, so that wiring that runs vertically through the all-solid-state battery 1 is not necessary.

[0058] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications and variations are possible within the scope of the gist of the present invention as set forth in the claims. [Explanation of symbols]

[0059] 1 All-solid-state battery 10 Electrode laminate 20 Exterior film 21 Inner resin layer 22 Metal layer 23 Outer resin layer 30 First electrode laminate 40 Second electrode laminate 50 Single-layer sheet electrode 60 positive electrode 61 Positive electrode current collector layer 62 Positive electrode active material layer 70 negative electrode 71 Negative electrode current collector layer 72 Negative electrode active material layer 80 Solid electrolyte layer 90 First tab lead 100 First negative electrode convergence body 110 First clad material 120 Second tab lead 130 First positive electrode convergence body 140 Second clad material 150 Third Tab Lead 160 Second positive electrode convergence body 170 4th Tab Reed 180 5th Tabreed 190 Second negative electrode convergence body 200 6th Tabreed 210 First internal connection 220 Second internal connection 230 CVS wiring terminal section 400 CVS

Claims

1. An electrode stack and an exterior film that houses the electrode stack, the electrode laminate has at least a first electrode laminate laminated so that both outermost surfaces of the laminate are negative electrode current collector layers, and a second electrode laminate laminated so that both outermost surfaces of the laminate are positive electrode current collector layers, a negative electrode convergent of a negative electrode current collector layer of the first electrode stack and a positive electrode convergent of a positive electrode current collector layer of the second electrode stack are connected in series, The exterior film has an inner resin layer, a metal layer, and an outer resin layer, an internal connection portion that electrically connects the negative electrode convergent and the positive electrode convergent to the metal layer is provided at one end in the width direction of the electrode stack, where the negative electrode convergent and the positive electrode convergent are connected in series.

2. At the other end in the width direction of the electrode stack, a positive electrode convergent of a positive electrode current collector layer of the first electrode stack and a negative electrode convergent of a negative electrode current collector layer of the second electrode stack are each joined to a tab lead, and 2. The all-solid-state battery according to claim 1, wherein the exterior film has an exposed portion at the other end in the width direction of the electrode laminate, where the metal layer is exposed and is electrically connected to an electrical device external to the all-solid-state battery.

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