WO2025192422A1 - Method for manufacturing power storage device - Google Patents

Abstract

Provided is a method for manufacturing a power storage device provided with a plurality of member units laminated in a lamination direction, said method including arranging a member unit continuous body in which a plurality of member units are connected by a connection part, folding the member unit continuous body at the position of the connection part, and removing the connection part after the member unit continuous body is folded.

Description

Method for manufacturing an electricity storage device

The present invention relates to a method for manufacturing an electricity storage device.

Patent Document 1 discloses a method for manufacturing an energy storage device that includes the steps of forming a first electrode unit with a convex portion formed on one surface of a first frame, forming a second electrode unit with a concave portion formed on the other surface of a second frame, and stacking the second electrode unit on the first electrode unit to prevent the stacking positions of the current collectors, separators, etc. from shifting from their correct positions during the stacking process for secondary batteries having a structure in which current collectors and separators are alternately stacked, and in which the convex portion of the first frame engages with the concave portion of the second frame during the stacking process.

Japanese Patent Application Laid-Open No. 2022-22899

In the manufacturing method for an energy storage device disclosed in Patent Document 1, convex portions are formed on the first frame and concave portions are formed on the second frame, and the convex portions of the first frame and the concave portions of the second frame are engaged to align them. However, Patent Document 1 exemplifies the thickness of the active material layer as 2 to 150 μm and the thickness of the current collector foil as 1 to 100 μm. Based on this, the cross-sectional thickness of the spacer portion including the convex portions and concave portions needs to be approximately 5 to 400 μm, which is the sum of the combined thickness of the positive and negative electrode active material layers (4 to 300 μm) and the current collector foil thickness (1 to 100 μm). Because the convex portions and concave portions of the engaging portion are smaller than the thickness of the spacer portion, high-precision and fine manufacturing techniques are required, and this method may not be easy to use to construct an energy storage device. Engaging the first frame and second frame may be particularly difficult when the electrode unit is large (e.g., approximately 1 m square).

The present invention was made by the inventors by focusing on the above-mentioned problem, and aims to provide a method for manufacturing an electricity storage device that allows for easy production of an electricity storage device.

A manufacturing method for an energy storage device according to one aspect of the present invention is a manufacturing method for an energy storage device having a plurality of component units stacked in a stacking direction, and includes arranging a component unit continuum in which the plurality of component units are connected by connecting portions, folding the component unit continuum at the positions of the connecting portions, and removing the connecting portions after folding the component unit continuum.

The method for manufacturing an electricity storage device according to the present invention makes it easy to manufacture an electricity storage device.

FIG. 1 is a perspective view showing the appearance of a power storage device according to an embodiment. FIG. 2 is a cross-sectional view showing the internal configuration of the electricity storage device according to the embodiment. FIG. 3A is a perspective view illustrating a configuration of a member unit included in the power storage device according to the embodiment. FIG. 3B is a cross-sectional view showing the configuration of a member unit included in the power storage device according to the embodiment. FIG. 4 is a flowchart showing manufacturing steps in the manufacturing method for the electricity storage device according to the embodiment. FIG. 5A is a plan view illustrating a step of arranging a member unit continuum in a manufacturing method for an energy storage device according to an embodiment. FIG. 5B is a plan view illustrating a step of arranging a separator continuous body in the manufacturing method for the energy storage device according to the embodiment. FIG. 6 is a perspective view showing the configuration of a frame member used in the step of folding the member unit continuous body in the manufacturing method for the electricity storage device according to the embodiment. FIG. 7A is a plan view illustrating a step of folding the member unit continuous body (after the fourth step) in the manufacturing method for the energy storage device according to the embodiment. FIG. 7B is a cross-sectional view illustrating a step of folding the member unit continuous body (after the fourth step) in the manufacturing method for the energy storage device according to the embodiment. FIG. 8A is a plan view illustrating a step of folding the member unit continuous body (after the fifth step) in the manufacturing method for the energy storage device according to the embodiment. FIG. 8B is a cross-sectional view illustrating a step of folding the member unit continuous body (after the fifth step) in the manufacturing method for the energy storage device according to the embodiment. FIG. 9A is a plan view illustrating a step of folding the member unit continuous body (again after completion of the third step) in the manufacturing method for the energy storage device according to the embodiment. FIG. 9B is a cross-sectional view illustrating a step of folding the member unit continuous body (after the third step is completed again) in the manufacturing method for the energy storage device according to the embodiment. FIG. 10A is a plan view illustrating a step of folding the member unit continuous body (after the fourth step is completed again) in the manufacturing method for the energy storage device according to the embodiment. FIG. 10B is a cross-sectional view illustrating a step of folding the member unit continuous body (after the fourth step is completed again) in the manufacturing method for the energy storage device according to the embodiment. FIG. 11 is a perspective view showing a step of folding the member unit continuous body in the manufacturing method for the energy storage device according to the embodiment. FIG. 12 is a cross-sectional view showing a step of cutting off the connection portion in the manufacturing method for the electricity storage device according to the embodiment. FIG. 13A is a plan view showing the configuration of a member unit continuum according to a first modified example of the embodiment. FIG. 13B is a plan view showing the configuration of the member unit continuum according to the first modification of the embodiment. FIG. 14A is a plan view showing the configuration of a member unit continuum according to a second modification of the embodiment. FIG. 14B is a plan view showing the configuration of a member unit continuum according to the second modification of the embodiment. FIG. 15A is a plan view illustrating a step of folding a member unit continuum in a manufacturing method for an energy storage device according to a second modification of the embodiment. FIG. 15B is a cross-sectional view illustrating a step of folding the member unit continuous body in the manufacturing method for an energy storage device according to the second modification of the embodiment. FIG. 16 is a cross-sectional view illustrating a step of folding the member unit continuous body in a manufacturing method for an energy storage device according to a second modification of the embodiment. FIG. 17 is a cross-sectional view illustrating a step of cutting off the connection portion in a manufacturing method for an electricity storage device according to the second modification of the embodiment. FIG. 18 is a plan view showing the configuration of a member unit continuum according to the third modification of the embodiment. FIG. 19 is a cross-sectional view illustrating a step of cutting off the connection portions after folding the member unit continuous body in a manufacturing method for an electricity storage device according to a third modified example of the embodiment. FIG. 20A is a plan view showing the configuration of a member unit continuum according to a fourth modified example of the embodiment. FIG. 20B is a plan view showing the configuration of a member unit continuum according to the fourth modification of the embodiment. FIG. 21 is a cross-sectional view illustrating a step of cutting off the connection portions after folding the member unit continuous body in a manufacturing method for an electricity storage device according to the fourth modification of the embodiment. FIG. 22 is a plan view showing the configuration of the electricity storage pack. FIG. 23 is a cross-sectional view showing the configuration of the electricity storage pack. FIG. 24 is a cross-sectional view showing the configuration of the electricity storage pack.

(1) A manufacturing method for an energy storage device according to one aspect of the present invention is a manufacturing method for an energy storage device including a plurality of component units stacked in a stacking direction, and includes arranging a component unit continuum in which the plurality of component units are connected by connecting portions, folding the component unit continuum at the positions of the connecting portions, and removing the connecting portions after folding the component unit continuum.

In accordance with one aspect of the present invention, a method for manufacturing an electricity storage device involves preparing a component unit series in which multiple component units are connected by connecting parts, folding the component unit series at the positions of the connecting parts, and then removing the connecting parts. In this way, by folding the component unit series in which multiple component units are connected by connecting parts at the positions of the connecting parts, multiple component units can be easily positioned and stacked. Furthermore, by removing the connecting parts after folding the component unit series, it becomes possible to stack the component units in the appropriate positions, making it easy to manufacture an electricity storage device.

Here, removing a connection includes cutting off the connection, removing a connection that has been joined by adhesive or the like, etc.

The component units that make up the component unit continuum include electrode units, separators, end units, end members, sealing members, and components that combine the functions of multiple of these components (for example, electrode units with separators, electrode units with sealing members, etc.). In addition, in this invention, components such as intermediate foils that do not function as components of an electricity storage device on their own are also referred to as component units.

Hereinafter, in this patent, an electrode unit with a sealing member will be referred to as an electrode member unit. Furthermore, an end unit in which a sealing member has already been placed on the active material layer forming surface will also be referred to as an end unit. The type of member unit used to construct the energy storage device can be selected appropriately depending on the shape of the energy storage device to be manufactured, the shape of the frame member, the design of the energy storage device, productivity, etc.

(2) In the method for manufacturing an electricity storage device described in (1) above, at least a portion of the component unit continuum may have a positive electrode active material layer disposed on one side of the current collector foil and a negative electrode active material layer disposed on the other side of the current collector foil.

The method for manufacturing an electricity storage device described in (2) above makes it easy to manufacture an electricity storage device (bipolar battery) in which a positive electrode active material layer is disposed on one side of the current collector foil and a negative electrode active material layer is disposed on the other side of the current collector foil.

(3) In the manufacturing method for a power storage device described in (1) or (2) above, the component unit continuum may be such that a plurality of component units each having a polygonal or circular shape with an even number of sides of four or more as viewed from the stacking direction are connected at the connection portions.

According to the manufacturing method for a storage battery device described in (3) above, a component unit continuum in which multiple component units are linearly connected by connectors can be used as the component unit continuum used in manufacturing the storage battery device. This makes it possible to supply the component unit continuum in roll form, thereby improving productivity during mass production.

(4) In the method for manufacturing an energy storage device described in any one of (1) to (3) above, the component unit continuum may be polygonal when viewed from the stacking direction, and the width of the connection portion may be shorter than the length of one side of the polygon.

The manufacturing method for a storage device described in (4) above produces a component unit continuum in which a connecting portion with a width shorter than the length of one side of a polygonal component unit is connected to that side. In this way, shortening the width of the connecting portion increases the degree of freedom in aligning the component units, and improves the alignment accuracy of the component units. Furthermore, shortening the width of the connecting portion and lengthening the connecting portion also makes it possible to invert the component unit continuum, and to stack the component units while inverting their top and bottom surfaces.

(5) In the method for manufacturing an energy storage device described in any one of (1) to (4) above, when folding the member unit series, the member units may be inserted into a frame member and the connection portions may be folded to cause the connection portions to protrude from the frame member, and when removing the connection portions, the connection portions protruding from the frame member may be cut.

According to the manufacturing method for an energy storage device described in (5) above, by inserting the component units into the frame member, the component unit series can be folded while the frame member positions the component units. Furthermore, by making the connection portions protrude from the frame member, the connection portions can be easily cut. Furthermore, by cutting the connection portions protruding from the frame member, the connection portions can be cut outside the frame member, which prevents contamination from entering the component units inside the frame member when the connection portions are cut.

Hereinafter, with reference to the drawings, a description will be given of an energy storage device and a manufacturing method thereof according to an embodiment of the present invention (including variations thereof). 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 examples only and are not intended to limit the present invention. In each figure, dimensions and the like are not strictly depicted. Furthermore, in each figure, the same or similar components are designated by the same reference numerals.

In the following explanation and drawings, the thickness direction of the energy storage device, the stacking direction of multiple component units, the thickness direction of the current collector foil or active material layer, the stacking direction of the current collector foil and active material layer, the arrangement direction of a pair of end members, or the up-down direction is defined as the Z-axis direction. Two different directions that intersect with the Z-axis direction are defined as the X-axis direction and the Y-axis direction. In this embodiment, the X-axis direction, Y-axis direction, and Z-axis direction are mutually perpendicular. Depending on the usage mode, it is possible that the Z-axis direction is not the up-down direction, but for ease of explanation, the following explanation will be made assuming that the Z-axis direction is the up-down direction.

In the following description, the positive X-axis direction refers to the direction of the X-axis arrow, and the negative X-axis direction refers to the direction opposite to the positive X-axis direction. Simply referring to the X-axis direction refers to both or either of the positive X-axis direction and the negative X-axis direction. The same applies to the Y-axis and Z-axis directions. Expressions indicating relative directions or attitudes, such as parallel and orthogonal, also include cases where the directions or attitudes are not strictly the same. Two directions being parallel (or orthogonal) not only means that the two directions are completely parallel (or orthogonal), but also means that the two directions are substantially parallel (or orthogonal), i.e., there is a difference of, for example, a few percent. In the following description, the term "insulation" means "electrical insulation." It is preferable that the insulating material be formed from a material with a volume resistivity of 1×10 ⁶ Ωm or more, more preferably 1×10 ⁷ Ωm or more, and even more preferably 1×10 ¹⁰ Ωm or more.

(Embodiment)
[1. Description of the Configuration of the Energy Storage Device 1]
First, the configuration of the energy storage device 1 according to the present embodiment will be described in detail. FIG. 1 is a perspective view showing the exterior of the energy storage device 1 according to the present embodiment. FIG. 2 is a cross-sectional view showing the internal configuration of the energy storage device 1 according to the present embodiment. FIG. 2 is a cross-sectional view of the energy storage device 1 of FIG. 1 taken along the YZ plane passing through line II-II, and shows each component included in the energy storage device 1. FIG. 3A is a perspective view showing the exterior of a component unit 10 which is an electrode unit 100 including a sealing member 210, and FIG. 3B is a cross-sectional view of the component unit 10 of FIG. 3A taken along the YZ plane passing through line IIIB-IIIB.

The power storage device 1 is a device that can charge with electricity from an external source and discharge electricity to the outside. In this embodiment, the power storage device 1 has a roughly hexagonal prism shape. Specifically, the power storage device 1 is a bipolar battery. The power storage device 1 is used as a battery for driving or starting the engine of mobile objects such as automobiles, motorcycles, watercraft, ships, snowmobiles, agricultural machinery, construction machinery, automatic guided vehicles (AGVs), or electric railway rolling stock. Examples of the above-mentioned automobiles include electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and fossil fuel (gasoline, diesel, liquefied natural gas, etc.) vehicles. Examples of the above-mentioned electric railway rolling stock include electric trains, monorails, linear motor cars, and hybrid trains equipped with both a diesel engine and an electric motor. The power storage device 1 can also be used as a stationary battery for home or business use.

As shown in Figures 1 and 2, the energy storage device 1 includes components such as an electrode unit 100, a sealing member 210, a separator 140, an end unit 101, an end unit 102, an end member 300, and an outer periphery sealing member 200. Some of these components, such as the electrode unit 100, the sealing member 210, and the separator 140, are required in large quantities for one energy storage device 1, while others, such as the end units 101 and 102, the end member 300, and the outer periphery sealing member 200, are required in only one or two quantities for one energy storage device 1. In the present invention, components that are required in large quantities for one energy storage device 1 are supplied continuously as a component unit continuum 10A, with the aim of facilitating production of the energy storage device 1 and improving productivity. Furthermore, components that are required in only one or two quantities for one energy storage device 1 are manufactured using a single battery component pre-formed to a predetermined size.

Furthermore, the questions of whether they can be supplied as a component unit continuum 10A and how many types of component unit continuum 10A can be supplied as a continuum depend on the shape of the component unit 10. If the component unit 10 is a polygon with an even number of sides (four or more) or a circle, the component unit 10 can be supplied as a continuum, and the number of component unit 10 that can be supplied as a continuum is up to two types for squares, three types for hexagons, and four types for octagons. Furthermore, if the component unit 10 is circular, by reducing the width of the connection portion 12, it is possible to supply more component unit continuums 10A.

In the following embodiment, a case where the component unit 10 is hexagonal in shape will be described. Up to three types of component unit continuum 10A can be supplied for hexagonal shapes, but in this embodiment, a case where two types of component unit 10 are used: (i) component unit continuum 10A, and (ii) separator continuum 140A will be described.

The component unit 10, end unit 101, and end unit 102 are hexagonal (regular hexagonal in this embodiment) plate-like structures in a planar view, and are stacked in the Z-axis direction. Here, in this embodiment, planar view refers to a view from the stacking direction (Z-axis direction). Also, in this embodiment, two component units 10 are illustrated stacked between end unit 101 and end unit 102, but the number of component units 10 stacked is not particularly limited. Separators 140 are arranged between component units 10, between component unit 10 and end unit 101, and between component unit 10 and end unit 102. A pair of end components 300 are arranged in the stacking direction (Z-axis direction), with end unit 101 in the negative Z-axis direction and end unit 102 in the positive Z-axis direction. The sealing member 210 is provided on the current collector foil 110 on which the positive electrode active material layer 120 and negative electrode active material layer 130 of the electrode unit 100 and end units 101 and 102 are not provided. Here, the thickness of each sealing member 210 is approximately the same as the thickness of the adjacent positive electrode active material layer 120 or negative electrode active material layer 130.

The stack 400 of component units 10 can be integrated by joining the sealing member 210. Furthermore, the periphery (outer periphery) of the stack 400 can be covered with the peripheral sealing member 200 to form the energy storage device 1.

[1.1 Description of the member unit 10, end units 101 and 102]
First, the configuration of the component unit 10 will be described in detail using Figures 3A and 3B. The component unit 10 is a single component unit in which active material layers are formed on both sides of a single current collector foil 110, and a sealing member 210 is disposed around the outer periphery of the active material layer. Each component unit 10 includes at least the current collector foil 110, a positive electrode active material layer 120 formed on one side of the current collector foil 110, a negative electrode active material layer 130 formed on the other side of the current collector foil 110, and a sealing member 210 around the outer periphery of the positive electrode active material layer 120 and the negative electrode active material layer 130. In this embodiment, the thickness (thickness in the stacking direction) of the component unit 10 is approximately 100 µm to 400 µm. Note that, for simplicity, the sealing member 210 around the outer periphery of the negative electrode active material layer 130 is omitted in Figure 3A.

Here, the sealing members 210 are provided on the collector foil 110 around the outer periphery of the positive electrode active material layer 120 and negative electrode active material layer 130 of the collector foil 110. The thickness of each sealing member 210 is approximately the same as the thickness of the adjacent positive electrode active material layer 120 and negative electrode active material layer 130. This means that if the thicknesses of the positive electrode active material layer 120 and the negative electrode active material layer 130 differ significantly, the thickness of the sealing members 210 adjacent to each active material must be different. As described above, the component unit 10 has active material layers formed on both sides of a single collector foil 110, and further has sealing members 210 arranged around the outer periphery of the active material layers. This increases the strength of the component unit 10 compared to when the sealing members 210 are not provided, which has the effect of reducing sheet tearing during stacking.

The current collector foil 110 is a plate-like member that is hexagonal in plan view (a regular hexagonal shape in this embodiment) and is a metal foil. As shown in FIG. 3B , the current collector foil 110 has two metal layers 111 and 112 that are aligned in the stacking direction (Z-axis direction). The metal layers 111 and 112 are plate-like portions that have the same size and shape in plan view. Hereinafter, of the metal layers 111 and 112, the metal layer 111 on which the positive electrode active material layer 120 is formed will also be referred to as the positive electrode metal layer 111, and the metal layer 112 on which the negative electrode active material layer 130 is formed will also be referred to as the negative electrode metal layer 112.

The positive electrode metal layer 111 is a metal layer of the current collector foil 110 located in the positive direction of the Z axis, and the negative electrode metal layer 112 is a metal layer of the current collector foil 110 located in the negative direction of the Z axis. In other words, the current collector foil 110 is formed by stacking the positive electrode metal layer 111 and the negative electrode metal layer 112 in the stacking direction, with the positive electrode metal layer 111 and the negative electrode metal layer 112 connected (contacting or bonded) to each other. One of the positive electrode metal layer 111 and the negative electrode metal layer 112 may be a metal foil, and the other may be a plated layer plated on the metal foil. Alternatively, both the positive electrode metal layer 111 and the negative electrode metal layer 112 may be metal foil. When both the positive electrode metal layer 111 and the negative electrode metal layer 112 are metal foil, the current collector foil 110 may be a clad material in which two metal foils are bonded together, or may comprise two metal foils that are connected (contacting) without being bonded to each other.

The positive electrode metal layer 111 is made of a metal such as aluminum, titanium, tantalum, or stainless steel, or an alloy thereof. Among these, aluminum or an aluminum alloy is preferred for the positive electrode metal layer 111, considering the balance between high potential resistance, high conductivity, and cost. The positive electrode metal layer 111 may be in the form of a plated layer, but foil is preferred for ease of processing and cost. In other words, aluminum foil is preferred for the positive electrode metal layer 111. The negative electrode metal layer 112 is made of a metal such as copper, nickel, stainless steel, or nickel-plated steel, or an alloy thereof, with copper or a copper alloy being preferred. The negative electrode metal layer 112 may be made of a plated layer or foil (copper foil), and examples of copper foil include rolled copper foil and electrolytic copper foil. The thickness (thickness in the stacking direction) of the current collector foil 110 is approximately 10 μm to 35 μm, and preferably approximately 20 μm to 30 μm. The thickness of the positive electrode metal layer 111 (thickness in the stacking direction) is approximately 5 μm to 20 μm, and the thickness of the negative electrode metal layer 112 (thickness in the stacking direction) is approximately 5 μm to 15 μm.

The current collecting foil 110 may be formed of a single layer (one sheet of metal foil) instead of multiple layers (two layers) of the positive electrode metal layer 111 and the negative electrode metal layer 112. In other words, the current collecting foil 110 may be formed of a material that can function as both the positive electrode metal layer 111 and the negative electrode metal layer 112, such as a single sheet of stainless steel. By forming the current collecting foil 110 from a single sheet of metal foil, the configuration of the energy storage device 1 can be simplified.

The positive electrode active material layer 120 is a positive electrode active material layer formed on one surface (the surface in the positive Z-axis direction) of the current collector foil 110. Specifically, the positive electrode active material layer 120 is formed on the positive electrode metal layer 111 (the outer surface (the surface in the positive Z-axis direction) of the positive electrode metal layer 111). A sealing member 210 is disposed on the outside of the positive electrode metal layer 111, and the positive electrode active material layer 120 is formed in a hexagonal shape (a regular hexagon in this embodiment) inside this. The thickness of the positive electrode active material layer 120 (thickness in the stacking direction) is approximately 50 μm to 100 μm.

The positive electrode active material layer 120 includes a positive electrode active material and, as necessary, optional components such as a conductive agent, a binder, a thickener, and a filler. Examples of the positive electrode active material include layered lithium transition metal oxides having an α-NaFeO ₂ crystal structure, such as LiM 1 O 2 (where M 1 is one or more metal elements selected from Li, Fe, Ni, Mn, Co, etc.), spinel-type lithium transition metal oxides, such as LiM 2 O 4 (where M 2 is one or more metal elements selected from Li, Fe, Ni, Mn, Co, etc.), and polyanion compounds, such as LiM 3 PO 4 , LiM 3 SiO 4 , and LiM 3 BO 3 (where M 3 is one or more metal elements selected from Li, Fe, Ni, Mn, Co, etc.). As the positive electrode active material, one of these compounds may be used alone, or two or more may be mixed and used. The conductive agent contained in the positive electrode active material layer 120 is not particularly limited as long as it has conductivity. Examples of the conductive agent include carbon black such as furnace black, acetylene black, and ketjen black, and natural or artificial graphite. Examples of the binder (binding agent) include fluororesin (polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), etc.), sulfonated EPDM, and styrene butadiene rubber (SBR). Examples of the thickener include polysaccharide polymers such as carboxymethyl cellulose (CMC) and methyl cellulose.

The negative electrode active material layer 130 is a negative electrode active material layer formed on the other surface (the surface facing the negative Z-axis) of the current collector foil 110. Specifically, the negative electrode active material layer 130 is formed on the negative electrode metal layer 112 (the outer surface (the surface facing the negative Z-axis) of the negative electrode metal layer 112). A sealing member 210 is disposed on the outside of the negative electrode metal layer 112, and the negative electrode active material layer 130 is formed in a hexagonal shape (a regular hexagon in this embodiment) inside this sealing member 210. The negative electrode active material layer 130 is formed to be larger in size than the positive electrode active material layer 120 when viewed transparently from the Z-axis direction. "Large size" in plan view means that the area in the XY plane is large and that no portion protrudes beyond the target area when viewed transparently from the Z-axis direction. In other words, when viewed transparently from the Z-axis direction, the negative electrode active material layer 130 has a large area and no portion protrudes into the opposing positive electrode active material layer 120. When viewed transparently from the Z-axis direction, the negative electrode metal layer 112 and the negative electrode active material layer 130 have the same or similar shapes, and the thickness of the negative electrode active material layer 130 (thickness in the stacking direction) is approximately 40 μm to 60 μm.

The negative electrode active material layer 130 contains a negative electrode active material and, if necessary, optional components such as a conductive agent, binder, thickener, and filler. The optional components such as the conductive agent, binder, thickener, and filler can be the same as those used in the positive electrode active material layer 120. The negative electrode active material typically uses a material that can absorb and release lithium ions. Specific examples include metals or semi-metals such as Si and Sn; metal oxides or semi-metal oxides such as Si oxide and Sn oxide; and carbon materials such as graphite and non-graphitic carbon (easily graphitizable carbon or non-graphitizable carbon).

Next, the configuration of end units 101 and 102 will be described. End unit 101 is positioned in the negative direction of the Z axis relative to component unit 10. End unit 102 is positioned in the positive direction of the Z axis relative to component unit 10. End units 101 and 102 are parts that sandwich multiple component units 10 in the Z axis direction.

The end unit 101 comprises at least a positive electrode metal layer 111 and a positive electrode active material layer 120 formed on the surface of the positive electrode metal layer 111 in the positive Z-axis direction. The configurations of the positive electrode metal layer 111 and positive electrode active material layer 120 of the end unit 101 are the same as the configurations of the positive electrode metal layer 111 and positive electrode active material layer 120 of the current collector foil 110 of the component unit 10 described above. The sealing member 210 is provided on the positive electrode metal layer 111 around the outer periphery of the positive electrode active material layer 120 on the surface of the end unit 101 on which the positive electrode active material layer 120 is provided. Here, the thickness of the sealing member 210 is approximately the same as the thickness of the positive electrode active material layer 120.

The end unit 102 comprises at least a current collector foil 110 and a negative electrode active material layer 130 arranged on the surface of the current collector foil 110 facing in the negative Z-axis direction. The configurations of the current collector foil 110 and negative electrode active material layer 130 provided in the end unit 102 are the same as the configurations of the current collector foil 110 and negative electrode active material layer 130 provided in the component unit 10 described above. The sealing member 210 is provided on the current collector foil 110 around the outer periphery of the negative electrode active material layer 130 on the surface of the end unit 102 on which the negative electrode active material layer 130 is provided. Here, the thickness of the sealing member 210 is approximately the same as the thickness of the negative electrode active material layer 130.

1.2 Description of the separator 140 and the end member 300
The separator 140 is a microporous sheet made of resin. The separator 140 is disposed between the component units 10, between the end units 101 and the component units 10, and between the end units 102 and the component units 10. Specifically, the separator 140 is disposed between the positive electrode active material layer 120 and the negative electrode active material layer 130. The separator 140 is formed in a hexagonal shape (a regular hexagonal shape in this embodiment) that is larger than the negative electrode active material layer 130 in a transparent planar view. In this embodiment, the size of the separator 140 is expressed as being the same as that of the current collector foil 110 in a planar view, but the size may be smaller or larger than that of the current collector foil 110 in a planar view. The thickness of the separator 140 (thickness in the stacking direction) is approximately 15 μm to 20 μm.

Separator 140 can be made from a woven fabric, a nonwoven fabric, a porous resin film, or the like. Of these, porous resin film is preferred. From the standpoint of strength, the main component of the porous resin film is preferably a polyolefin such as polyethylene or polypropylene. Separator 140 may also be a multilayer film in which a layer containing a filler is formed on the surface of such a porous resin film.

The end members 300 are members that are positioned closer to the ends of the energy storage device 1 in the stacking direction (Z-axis direction) than the multiple component units 10. In this embodiment, a pair of end members 300 are positioned at the ends of the energy storage device 1 closest to the negative Z-axis direction and the positive Z-axis direction. The pair of end members 300 are connected to the end units 101 and 102 (and the current collecting foils 110 provided therein). As a result, the pair of end members 300 sandwich the multiple component units 10 and end units 101 and 102 located between them from both sides in the stacking direction (Z-axis direction).

The end member 300 is formed from a conductive metal material such as aluminum, aluminum alloy, copper, copper alloy, or nickel, or a combination thereof, or a conductive material other than metal. Because the end member 300 is connected to the positive electrode metal layer 111, it is preferably formed from the same material as the positive electrode metal layer 111, such as aluminum. The end member 300 is electrically connected to another end member 300 provided in another energy storage device 1 via another conductive member (bus bar, cooling plate, etc., not shown). The thickness of the end member 300 (thickness in the stacking direction) is approximately 0.5 mm to 3 mm. The energy storage device 1 may have another conductive member on the outside of the end member 300 (outside in the Z-axis direction). A mechanism for applying pressure to the end member 300 from the outside may also be provided to reduce resistance.

[1.3 Description of the sealing member 210 and the peripheral sealing member 200]
The sealing members 210 are provided on both sides of the current collector foil 110 on the outer periphery of the positive electrode active material layer 120 and/or negative electrode active material layer 130 of the component unit 10 and the end units 101, 102. The thickness of each sealing member 210 is approximately the same as the thickness of the adjacent positive electrode active material layer 120 or negative electrode active material layer 130. The sealing members 210 are components that join battery components together and have a hexagonal outer shape (a regular hexagon in this embodiment) in a plan view.

The peripheral sealing member 200 is a dense resin layer provided around (the outer periphery of) the energy storage device 1.

The sealing member 210 and the peripheral sealing member 200 are formed from insulating materials such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyamide (PA), ABS resin, or composite materials thereof.

In the above explanation, the sealing member 210 is described as part of a component unit 10 such as the component unit 10, end units 101 and 102, but it is also possible to stack the sealing member 210 as a standalone component unit 10. However, if the same sealing member 210 is used for the positive electrode active material layer 120 side and the negative electrode active material layer 130 side, the positive electrode active material layer 120 and the negative electrode active material layer 130 must be approximately the same thickness. If the thicknesses of the positive electrode active material layer 120 and the negative electrode active material layer 130 differ significantly, the thickness of the sealing member 210 on the positive electrode side and the negative electrode side must be different.

As such, the sealing member 210 is a member that seals between the component unit 10 and the separator 140, between the end unit 101 and the separator 140, and between the end unit 102 and the separator 140. The sealing member 210 may be an adhesive or pressure-sensitive adhesive that does not adversely affect battery performance. Examples of adhesives that may be used include acrylic resin-based adhesives, α-olefin-based adhesives, urethane resin-based adhesives, ether-based cellulose-based adhesives, ethylene-vinyl acetate resin emulsion adhesives, epoxy resin-based adhesives, vinyl chloride resin solvent-based adhesives, cyanoacrylate-based adhesives, silicone-based adhesives, nitrocellulose adhesives, and phenolic resin-based adhesives. Examples of pressure-sensitive adhesives include acrylic-based adhesives, silicone-based adhesives, and rubber-based adhesives. Alternatively, the sealing member 210 may be made of adhesive tape with adhesive applied to both sides of a resin tape. Using double-sided tape for the sealing member 210 allows the component units 10 to be joined together with the sealing member 210 after stacking, thereby integrating the laminate 400.

The peripheral sealing member 200 is a dense resin layer provided around the periphery of the energy storage device 1, and is a cylindrical (hexagonal cylindrical) member that seals the energy storage device from the outside. After stacking the battery components using the method described below and removing the connecting portions of the component units 10, the stacked body 400 is removed from the frame member 30 and the peripheral sealing member 200 is applied to its periphery, thereby covering the periphery of the energy storage device 1 with a resin layer. Alternatively, the energy storage device 1 can be constructed by using the frame member 30 used for stacking as is, joining the peripheries of the frame member 30 and stacked body 400 with the peripheral sealing member 200, and then joining a frame member lid.

In the above description of the present invention, the terminal structure, gas exhaust valve, gas exhaust structure, cooling structure, electrolyte injection port, etc., which are essentially required for the energy storage device 1, have been omitted as they are not relevant to the spirit of the present invention.

The separator 140 of the energy storage device 1 is impregnated with an electrolytic solution to form an electrolyte layer (not shown). In this embodiment, the electrolyte layer is a non-aqueous liquid electrolyte (electrolytic solution), but a gel electrolyte or the like may also be used. Any known electrolyte can be used as appropriate. The electrolytic solution (nonaqueous electrolyte) may be one in which an electrolyte salt is dissolved in a non-aqueous solvent. Examples of non-aqueous solvents include cyclic carbonates such as ethylene carbonate (EC) and propylene carbonate (PC), and chain carbonates such as diethyl carbonate (DEC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC). A lithium salt is preferred as the electrolyte salt. Examples of the lithium salt include inorganic lithium salts such as LiPF ₆ , LiPO ₂ F ₂ , LiBF ₄ , LiClO ₄ , LiN(SO ₂ F) ₂ , and LiN(SO ₂ CF ₃ ).

In the above configuration, the separator 140, the positive electrode active material layer 120 and the negative electrode active material layer 130 sandwiching the separator 140 in the Z-axis direction, and the positive electrode metal layer 111 and the negative electrode metal layer 112 sandwiching these in the Z-axis direction may be referred to as a single energy storage element. In this case, the energy storage device 1 can also be described as an energy storage element having a configuration in which multiple energy storage elements stacked in the Z-axis direction are sandwiched between a pair of end members 300 in the Z-axis direction, and the periphery of these is surrounded by a sealing member 210 and a peripheral sealing member 200.

[1.4 Description of connection parts 12, 21]
The connection portions 12, 21 are portions that connect the component units 10 to each other in the component unit continuous body 10A and the separator continuous body 140A. These portions do not necessarily have to be made of the same material as the respective component units 10; they may be made of a material different from the material of each component unit 10 and be adhered or bonded to each component unit 10. For example, while the component unit 10 is made of a metal current collector foil 110, the connection portion 12 does not have to be made of metal and may be a flexible resin film such as PET resin. Using such a resin film for the connection portion 12 can prevent metal contamination when the connection portion 12 is separated. Furthermore, the component unit 10 and the connection portion 12 may be joined using adhesive tape or the like. In this case, when separating the connection portion 12, the connection portion 12 can be separated from the component unit 10 by removing the adhesive tape. Similarly, in the separator continuous body 140A, the material of the member units 10 and the material of the connecting portions 21 may be different, or they may be bonded or joined to the member units 10.

[Description of the embodiment]
Next, a method for manufacturing the energy storage device 1 according to the present embodiment will be described in detail. FIG. 4 is a flowchart showing manufacturing steps in the method for manufacturing the energy storage device 1 according to the present embodiment. In this example, the manufacturing steps will be described in the order of the steps in FIG. 4. FIG. 5A is a plan view showing the appearance of a component unit continuous body 10A in the method for manufacturing the energy storage device 1 according to the present embodiment. FIG. 5B is a plan view showing the appearance of a separator continuous body 140A in the method for manufacturing the energy storage device 1 according to the present embodiment. FIG. 6 is a perspective view showing the configurations of the frame member 30, the component unit continuous body 10A, and the separator continuous body 140A in the method for manufacturing the energy storage device 1 according to the present embodiment.

As shown in Figure 4, the manufacturing method for the energy storage device 1 of this embodiment consists of one process preparation step and 11 processes. First, in the process preparation step, the components for constructing the energy storage device 1 are prepared. The main components to be prepared are the frame member 30, the component unit continuous body 10A, the separator continuous body 140A, the end member 300, and the end units 101 and 102.

Here, as shown in FIG. 6, the frame member 30 is a frame-shaped member having a hexagonal (regular hexagonal) shape in a plan view, and includes a pair of side walls 31, a pair of side walls 32, a pair of side walls 33, and a bottom wall 34. The pair of side walls 31 are flat wall portions positioned corresponding to the component unit continuum 10A, and are formed with a pair of openings 31a into which the connecting portions 12 of the component unit continuum 10A are inserted. The pair of side walls 32 are flat wall portions positioned corresponding to the separator continuum 140A, and are formed with a pair of openings 32a into which the pair of connecting portions 21 of the separator continuum 140A are inserted. Note that, in this embodiment, no openings are formed in the pair of side walls 33. In this embodiment, the shape of the frame member 30 is a regular hexagon, the same shape as the component unit 10, to engage the component unit 10 and its connecting portions 12 therein. However, since the purpose of the frame member 30 is to align the component unit 10, the frame member 30 does not need to have the same shape as the component unit 10 as long as that purpose is achieved.

The size of the internal space of the frame member 30 (the size of the hexagon formed by the inner surfaces of a pair of side walls 31, a pair of side walls 32, and a pair of side walls 33) is formed to be the same as the external size of the current collector foil 110 (and intermediate foil 11) in a plan view. This makes it easy to position the current collector foil 110 (and intermediate foil 11) by placing the current collector foil 110 (and intermediate foil 11) within the frame member 30. The size of the internal space of the frame member 30 may be formed to be slightly larger than the external size of the current collector foil 110 (and intermediate foil 11), taking dimensional tolerances (errors) into consideration. The material of the frame member 30 may be metal such as aluminum or stainless steel, or a resin material such as polyethylene or polypropylene.

In the first step, the end member 300 is inserted into the frame member 30 from the Z-axis direction. Here, the end member 300 is pre-formed to a predetermined dimension and is inserted into the frame member 30 as a standalone member.

When supplying component units 10 to a frame member 30, there are two methods: supplying them as a component unit continuum 10A, or installing them as individual component units 10. In this embodiment, however, only the component units 10 and separators 140 are supplied as a continuum, and the other component units 10 are stacked as individual components.

In the second step, the end unit 101 is inserted as a separate component into the frame member 30 from the Z-axis direction. The end unit 101 includes at least a positive electrode metal layer 111, a positive electrode active material layer 120 formed on the surface of the positive electrode metal layer 111 facing in the positive Z-axis direction, and a sealing member 210 provided on the outer periphery of the positive electrode active material layer 120.

In the third step, separators 140 are inserted from the positive Z-axis direction of frame member 30 using separator continuum 140A. As shown in Figure 5B, separator continuum 140A has a shape in which hexagonal separators 140 are joined in a linear fashion by connecting portions 21, and can be supplied to frame member 30 as a roll-shaped continuum.

As shown in Figure 6, the separator 140 and connecting portion 21 of the separator continuum 140A are configured to engage with the frame member 30, and after the separator continuum 140A is inserted into the frame member 30, the connecting portion 21 (connecting portion 21b in Figure 7A) and the next separator 140 (separator 140b in Figure 7A) protrude outside the frame member 30 through the opening 32a in the frame member 30.

In the fourth step, the component unit 10 is inserted from the positive Z-axis direction of the frame member 30 in which the separator 140 is arranged, using a component unit continuum 10A. In this step, as shown in Figure 5A, a component unit continuum 10A is used in which the hexagonal (regular hexagonal) component units 10 shown in Figure 3A and intermediate foils 11 with hexagonal through holes formed in hexagonal (regular hexagonal) current collecting foils 110 are alternately connected by connecting portions 12.

The component unit 10 has a positive electrode active material layer 120 formed on one surface (the surface facing the positive Z-axis direction) and a negative electrode active material layer 130 formed on the other surface (the surface facing the negative Z-axis direction). In addition, a sealing member 210 is provided around the outer periphery of the positive electrode active material layer 120 and the negative electrode active material layer 130.

This component unit continuum 10A is a roll-shaped continuum comprising a plurality of component units 10, a plurality of intermediate foils 11, and a plurality of connecting portions 12 that alternately connect these. In this embodiment, as shown in Figure 5A, the connecting portion 12a, component unit 10a, connecting portion 12b, intermediate foil 11a, connecting portion 12c, component unit 10b, connecting portion 12d, and intermediate foil 11b are arranged in a row (linearly) in the Y-axis direction.

As shown in Figure 6, the component units 10 and connection portions 12 of the component unit continuum 10A are configured to engage with the frame member 30, and after the component unit continuum 10A is inserted into the frame member 30, the connection portions 12 (connection portion 12b in Figure 7A) and intermediate foil 11 (intermediate foil 11a in Figure 7A) protrude outside the frame member 30 through the opening 31a in the frame member 30.

In this embodiment, the intermediate foil 11 is made of the same material as the current collector foil 110, has the same shape and size as the current collector foil 110, and may have a large through-hole formed in the center. Through-hole 11a1 is formed in intermediate foil 11a, and through-hole 11b1 is formed in intermediate foil 11b. The through-holes (through-holes 11a1 and 11b1) are hexagonal (regular hexagonal) in plan view, penetrating the intermediate foil 11 in the Z-axis direction, and are larger in size than the combined part of the positive electrode active material layer 120 and the sealing member 210 formed around its periphery in plan view. In this embodiment, the through-holes (through-holes 11a1 and 11b1) are smaller in size than the combined part of the negative electrode active material layer 130 and the sealing member 210 formed around its periphery, and are smaller in size than the separator 140. In this manner, the intermediate foil 11 is a ring-shaped member that is hexagonal (regular hexagonal) in plan view.

The connection portion 12 is a portion of the component unit continuum 10A that connects the opposing edges of the component unit 10 and the intermediate foil 11. This portion does not necessarily have to be made of the same material as the component unit 10 and the intermediate foil 11; it may be made of a different material and later glued or joined to the component unit 10 and the intermediate foil 11. For example, the current collector foil 110 that forms the base of the component unit 10 is made of metal, but the connection portion 12 does not have to be metal and can be a flexible resin film such as PET resin. Using a resin film for the connection portion 12 in this way prevents metal contamination when the connection portion 12 is separated. The component unit 10 and connection portion 12 may also be joined using adhesive tape, etc. In this case, the connection portion 12 can be removed by removing the adhesive tape without cutting.

In this embodiment, the connection portion 12 connects one side of the hexagonal (regular hexagonal) current collector foil 110 in the positive Y-axis direction to one side of the hexagonal (regular hexagonal) intermediate foil 11 in the negative Y-axis direction. The width of the connection portion 12 in the X-axis direction is shorter than the length of one side of the current collector foil 110 and shorter than the length of one side of the intermediate foil 11. In other words, the width of the connection portion 12 in the X-axis direction is shorter than the length of one side of the current collector foil 110 in the positive Y-axis direction and shorter than the length of one side of the intermediate foil 11 in the negative Y-axis direction.

In the manufacturing method of the energy storage device 1 of this embodiment, the component unit continuum 10A is positioned rotated about the Z axis relative to the separator continuum 140A, so the X-axis and Y-axis directions of both change. Specifically, when a regular hexagonal frame member 30 as shown in Figure 6 is used, the component unit continuum 10A and the separator continuum 140A are stacked at an angle of approximately 60° or 120° on the YX plane.

FIG. 6 is a perspective view showing the configuration of the frame member 30, component unit continuum 10A, and separator continuum 140A in the manufacturing method for the energy storage device 1 according to this embodiment. FIG. 7A is a plan view showing the state after the fourth step in the manufacturing method for the energy storage device 1 according to this embodiment. FIG. 7B shows a cross section of the YZ plane passing through line VIIB-VIIB in the configuration of FIG. 7A. For ease of explanation, in FIG. 7B, the current collector foil 110 is not separated into the positive electrode metal layer 111 and the negative electrode metal layer 112, but is shown as an integrated positive electrode metal layer 111 and negative electrode metal layer 112. The same applies to subsequent illustrations of the current collector foil 110. For simplicity, the end member 300 installed in the first step and the end unit 101 installed in the second step are not shown. This also applies to the cross-sectional views that follow.

As shown in Figure 6, the component unit continuum 10A and the connecting portion 12 are configured to engage with the frame member 30, and after the component unit continuum 10A is inserted into the frame member 30, the connecting portion 12 (connecting portion 12b in Figure 7A) and the next intermediate foil 11 (intermediate foil 11a in Figure 7A) joined to the connecting portion 12 protrude outside the frame member 30 through the opening 31a in the frame member 30.

In the fifth step, the connection portion 12 (connection portion 12b in Figure 7A) protruding from the opening 31a of the frame member 30 of the component unit continuous body 10A previously stacked in the fourth step is folded, the component unit continuous body 10A is folded back, and the intermediate foil 11 (intermediate foil 11a in Figure 7A) is inserted into the frame member 30 from the positive direction of the Z axis. As a result, the connection portion 12 (connection portion 12c in Figure 7A) and the component unit 10 (component unit 10b in Figure 7A) joined to the connection portion 12 protrude outside the frame member 30 through the opening 31a of the frame member 30.

FIG. 8A is a plan view showing the state after the fifth step in the manufacturing method for the energy storage device 1 according to this embodiment. FIG. 8B shows a cross section of the configuration in FIG. 8A taken along the YZ plane passing through line VIIIB-VIIIB.

In steps 5 and beyond, steps 3, 4, and 5 are repeated multiple times according to the number of stacked electrode member units, thereby increasing the number of series-connected bipolar batteries, which is one of the main applications of the present invention. Figure 9A is a plan view showing the state after step 3 is performed again after step 5 in the manufacturing method for energy storage device 1 according to this embodiment. Figure 9B shows a cross section in the YZ plane passing through line IXB-IXB in the configuration of Figure 9A. Figure 10A is a plan view showing the state after step 4 is performed again after step 3 in the manufacturing method for energy storage device 1 according to this embodiment. Figure 10B shows a cross section in the YZ plane passing through line XB-XB in the configuration of Figure 10A.

Figure 11 is a perspective view showing the process of folding and stacking the component unit continuous body 10A and the separator continuous body 140A in the manufacturing method for the energy storage device 1 according to this embodiment. To make the drawing easier to see, Figure 11 shows the frame member 30 separated from the electrode component unit 10 and the lengths of the connection portions 12, 21 as being long. For simplicity's sake, the end member 300 installed in the first step and the end unit 101 installed in the second step are not shown in this drawing.

After the target number of stacks has been reached by repeating steps 3 through 5 multiple times, in step 6, the connecting portions 21 of the separator continuous body 140A previously stacked in step 3 that protrude from the opening 32a of the frame member 30 are folded, the separator continuous body 140A is folded back, and the separator 140 is inserted into the frame member 30 from the positive direction of the Z axis. As a result, the connecting portions 21 and the next separator 140 joined to the connecting portions 21 protrude outside the frame member 30 through the opening 32a of the frame member 30.

In the seventh step, the end unit 102 is inserted as a separate member from the Z-axis direction of the frame member 30. The end unit 102 includes at least a current collector foil 110, a negative electrode active material layer 130 disposed on the surface of the current collector foil 110 facing in the negative Z-axis direction, and a sealing member 210 provided on the outer periphery of the negative electrode active material layer 130.

In the eighth step, the end member 300 is inserted as a separate member from the Z-axis direction of the frame member 30.

In the ninth step, the folded connecting portions 12, 21 protruding from the openings 31a, 32a of the frame member 30 are cut. By having the connecting portions 12, 21 protruding from the frame member 30, they can be easily cut. Furthermore, by cutting the connecting portions 12, 21 protruding from the frame member 30, contamination caused by cutting can be prevented from entering the stack 400. Figure 12 is a cross-sectional view showing the state in which the connecting portions 12, 21 have been cut in the ninth step of the manufacturing method for the energy storage device 1 according to this embodiment. (For simplicity, only a portion of the stacked component units 10 is shown.) Furthermore, in this example, the connecting portions 12, 21 were cut after the series of stacking steps were completed, but the present invention is not limited to this, and the connecting portions 12, 21 can be cut at any time. Furthermore, cut marks are left on the cut surfaces.

The component unit 10 and the connection part 12 may be joined using adhesive tape or the like. In this case, there is no need to cut the connection part 12 when removing it; it can be removed by simply removing the adhesive tape, and it can be removed at any time.

In the tenth step, the laminate 400, which has been subjected to steps 9 and above, is removed from the frame member 30 and heated and compressed from the outside, thereby applying heat to the sealing member 210 and integrating the laminate 400. In this case, integration can be achieved without heating by using an adhesive, pressure-sensitive adhesive, or adhesive tape for the sealing member 210. Furthermore, the integration does not necessarily have to be performed after cutting the connecting portions 12 and 21; it is also possible to cut the connecting portions 12 and 21 after integration.

In step 11, the laminate 400 integrated in step 10 is removed from the frame member 30, and the outer periphery (side surface) of the laminate 400 is sealed with the outer periphery sealing member 200. This is because if the outer periphery of the energy storage device 1 is left covered with the sealing member 210, moisture in the air may affect performance during long-term use. For this purpose, a dense, low-moisture permeability outer periphery sealing member 200 must be placed around (covers) the periphery of the energy storage device 1. In this embodiment, the outer periphery sealing member 200 is a dense resin layer provided around the periphery of the energy storage device 1. Furthermore, by sealing the outer peripheries of the frame member 30 and the laminate 400 with the outer periphery sealing member 200, the frame member 30 may be used as is as a case for the energy storage device 1. The energy storage device 1 may also be constructed by joining a lid to the frame member 30, on which component units 10 and the like are stacked, with an adhesive or the like. In this case, the energy storage device 1 may be constructed by joining the lid to the frame member 30 with adhesive or the like.

[Effect description]
As described above, according to the manufacturing method of the energy storage device 1 according to the embodiment of the present invention, a component unit string 10A in which a plurality of component units 10 are connected by the connection portions 12 is arranged, the component unit string 10A is folded at the position of the connection portions 12, and then the connection portions 12 are removed. In this manner, by folding the component unit string 10A in which a plurality of current collector foils 110 (component units 10) are connected by the connection portions 12 at the position of the connection portions 12, the plurality of current collector foils 110 (component units 10) can be easily positioned and stacked. By folding the component unit string 10A and then removing the connection portions 12, it becomes possible to stack the component units 10 in appropriate positions, and the energy storage device 1 can be easily manufactured.

In Figure 7B and other figures, the current collector foil 110 is illustrated as an integrated positive electrode metal layer 111 and negative electrode metal layer 112, but in this embodiment, the current collector foil 110 may be formed from a single metal foil such as stainless steel foil. This further simplifies the configuration of the current collector foil 110.

The manufacturing method for the energy storage device 1 makes it easy to manufacture an energy storage device 1 (bipolar battery) in which a positive electrode active material layer 120 is disposed on one side of the current collector foil 110 and a negative electrode active material layer 130 is disposed on the other side of the current collector foil 110. Therefore, even when using large current collector foils 110 (component units 10), multiple current collector foils 110 (component units 10) can be easily positioned, making it easy to manufacture relatively large bipolar batteries. Furthermore, the use of a roll-shaped component unit continuum 10A allows for continuous supply, making it possible to mass-produce large bipolar batteries.

According to the manufacturing method for the energy storage device 1, a component unit continuum 10A is arranged in which multiple polygonal (hexagonal in this embodiment) or circular component units 10 with an even number of sides of four or more when viewed in the stacking direction are connected by connecting portions 12. This allows two connecting portions 12 to be arranged on the current collector foil 110 (component unit 10) at opposing positions on the polygon or circle, making it possible to form the component unit continuum 10A in a straight line. This allows multiple current collector foils 110 (component units 10) to be easily folded at the connecting portions 12. Forming the component unit continuum 10A in a straight line makes it possible to supply the component unit continuum 10A in roll form, improving productivity during mass production.

In order to supply multiple roll-shaped component unit continuums 10A to a frame member 30, fold the connecting portions 12, and store and stack the component units 10 within the frame member 30, there are certain restrictions on the shape of the component units 10 and the shape of the frame member 30. The component units 10 must be polygonal or circular with an even number of sides. If the shape is a polygonal shape with an even number of sides, the connecting portions 12 can be placed on two opposing sides of each component unit 10, allowing the component unit continuum 10A to be formed in a straight line. This allows the connecting portions 12 to be easily folded at predetermined positions, allowing the component units 10 to be stacked continuously. When supplying component units 10 to a frame member 30, there are two methods: supplying them as component unit continuums 10A, or placing individual component units 10 on the frame member 30 and stacking them. However, the maximum number of component unit continuums 10A that can be supplied to one frame member 30 is determined by the shape of the component units 10. Two component unit strings 10A can be supplied to the frame member 30 if the component units 10 are rectangular, three if they are hexagonal, and four if they are octagonal. If the component units 10 are circular, component units 10 can be supplied to the frame member 30 from many component unit strings 10A if the width of the connection portions 12 is sufficiently small compared to the circular size of the component units 10. However, because the energy storage devices 1 also have a cylindrical shape, when the energy storage devices 1 are assembled into an energy storage pack, excess space is required, resulting in a lower energy density of the energy storage pack. When stacking with a rectangular frame member 30, more than two battery components are usually required, so two component unit strings 10A are continuously supplied, and the other battery components must be supplied individually.

According to the manufacturing method of the energy storage device 1, a component unit continuum 10A is arranged in which a connecting portion 12 having a width shorter than the length of one side of a current collecting foil 110 (component unit 10) that is polygonal (hexagonal in this embodiment) when viewed in the stacking direction is connected to that side. In this way, shortening the width of the connecting portion 12 improves the degree of freedom in aligning the component unit 10, and improves alignment accuracy. Reducing the width of the connecting portion 12 makes it easier to separate the connecting portion 12, and the shorter width of the connecting portion 12 shortens the portion to be separated, reducing the generation of contamination (contamination, metal powder, etc.).

According to the manufacturing method of the energy storage device 1, the component units 10 are inserted into the frame member 30, and the connection portions 12 are caused to protrude from the frame member 30. By inserting the component units 10 into the frame member 30 in this way, the component unit series 10A can be folded while the component units 10 are positioned by the frame member 30. By controlling the dimensional accuracy of the frame member 30 and the component units 10, the positioning accuracy between the component units 10 can be easily improved.

In a bipolar structure energy storage device 1, each component unit 10 is connected in series in a stacking method. Therefore, to prevent short circuits between each component unit 10, if the connection parts 12 of the component unit series 10A are conductive, it is necessary to cut off the conductivity. By cutting off the connection parts 12 protruding from the frame member 30, the connection parts 12 can be cut off outside the frame member 30, thereby reducing the impact of contamination caused by cutting off and creating an energy storage device 1 suitable for a bipolar battery. The connection parts 12 can be cut off all at once after all the stacking is complete, or the connection parts 12 can be cut off individually after each component unit 10 is stacked on the frame member 30, or multiple connection parts 12 can be cut off at a time.

The connection portion 12 may be joined using adhesive tape or the like. In this case, when removing the connection portion 12, the connection portion 12 and the component unit 10 can be removed by removing the adhesive tape without cutting.

Note that while the stacking effect of the component unit continuum 10A, which is the electrode unit 100 equipped with the sealing member 210, has been described here, the same effect can be achieved with the separator continuum 140A. Furthermore, the same effect can be achieved when other component unit continuums 10A, such as end units 101 and 102, end members 300, and sealing members 210, are arranged.

[4. Description of Modifications]
Although the energy storage device 1 and the manufacturing method thereof according to the present embodiment have been described above, the present invention is not limited to the above embodiment. The embodiment disclosed herein is illustrative in all respects and is not restrictive, and the scope of the present invention includes all modifications within the meaning and scope of the claims.

(Variation 1)
In the above embodiment, the component units 10 and the intermediate foil 11 included in the component unit continuum 10A have a hexagonal shape (regular hexagonal shape) in a plan view, but are not limited to this. Fig. 13A is a plan view showing the configuration of the component unit continuum 10Aa according to Modification 1 of this embodiment, and Fig. 13B is a plan view showing the configuration of the component unit continuum 10A according to Modification 1 of this embodiment. Figs. 13A and 13B are views corresponding to Fig. 5A.

As shown in FIG. 13A, the component unit continuum 10Aa in this modified example includes component units 10c and intermediate foils 11c each having a quadrangular (square) shape in plan view. In the component unit 10c, the current collector foil 110, positive electrode active material layer 120, and negative electrode active material layer 130 also have a quadrangular (square) shape in plan view, and a sealing member 210 is provided on the outer periphery of each active material. A through-hole 11c1 having a quadrangular (square) shape in plan view is formed in the intermediate foil 11c. Similarly, the frame member 30, separator 140, end units 101, 102, and end member 300 also have a quadrangular (square) shape in plan view. The remaining configuration of this modified example is the same as that of the above-described embodiment, and therefore detailed description will be omitted. The component unit continuum 10A may have a rectangular shape other than a square in plan view, or may be an octagon, decagon, or the like.

As shown in Figure 13B, the component unit continuum 10Ab in this modified example also includes a component unit 10d and intermediate foil 11d that are circular in plan view. In the component unit 10d, the current collector foil 110, positive electrode active material layer 120, and negative electrode active material layer 130 also have a circular shape in plan view. In addition, a ring-shaped sealing member 210 is provided on the outer periphery of each active material. A through hole 11d1 that is circular in plan view is formed in the intermediate foil 11d. The frame member 30, separator 140, end units 101, 102, and end member 300 also have a circular shape in plan view. The other configurations of this modified example are the same as those of the above embodiment, so detailed description will be omitted. The component unit continuum 10A may also have an oval or elliptical shape in plan view.

By arranging the component unit continuum 10A in this way, component units 10 can be stacked using component unit continuum 10A in which multiple polygonal or circular current collecting foils 110 with an even number of sides are connected at connecting portions 12 when viewed from the stacking direction (Z-axis direction).

With the configuration of this modified example, an electricity storage device can be manufactured in the same manner as the above embodiment, and the same effects as the above embodiment can be achieved. In other words, according to the method for manufacturing an electricity storage device, by arranging a component unit continuum 10A in which multiple current collector foils 110, each of which is an even number of polygons with four or more sides or a circle, are connected by connecting portions 12, two connecting portions 12 can be positioned opposite each other on the component unit 10, and the component unit continuum 10A can be formed in a straight line. This allows multiple component units 10 to be easily folded at the positions of the connecting portions 12. By forming the component unit continuum 10A in a straight line, the component unit continuum 10A can be supplied in a roll.

(Variation 2)
In the above embodiment, the component unit continuum 10A includes an intermediate foil 11 having a through hole formed therein. However, the intermediate foil 11 may not be included. In Modification 2, an example of manufacturing a bipolar type energy storage device by folding a plurality of component unit continuums 10A will be described. FIG. 14A is a plan view showing the configuration of a component unit continuum 10Ac according to Modification 2 of the present embodiment, and FIG. 14B is a plan view showing the configuration of a component unit continuum 10Ad according to Modification 2 of the present embodiment. FIGS. 14A and 14B correspond to FIG. 5A. FIG. 15A is a plan view showing a step of folding the component unit continuums 10Ac and 10Ad in the manufacturing method for an energy storage device according to Modification 2 of the present embodiment. FIG. 15B is a cross-sectional view showing the state in which the component unit continuums 10Ac and 10Ad are inserted to form a first layer in the manufacturing method for an energy storage device according to Modification 2 of the present embodiment. FIGS. 15A and 15B correspond to FIGS. 7A and 7B. Fig. 16 is a cross-sectional view showing a state in which the component unit continuous bodies 10Ac and 10Ad are folded and then inserted into the frame member 30 to form a second layer in the manufacturing method for an energy storage device according to Modification 2 of the present embodiment. Fig. 16 is a view corresponding to Fig. 10B. Fig. 17 is a cross-sectional view showing a step of cutting off the connection portions 12 in the manufacturing method for an energy storage device according to Modification 2 of the present embodiment. Fig. 17 is a view corresponding to Fig. 12.

As shown in FIG. 14A, the component unit continuum 10Ac in this modified example has a configuration in which a plurality of component units 10e and a plurality of component units 10f are alternately connected by connecting portions 12. Component unit 10e has a positive electrode active material layer 120 formed on the surface of positive electrode metal layer 111, which is the positive electrode current collector foil of current collector foil 110, in the positive Z-axis direction. Component unit 10f has a positive electrode active material layer 120 formed on the surface of positive electrode metal layer 111 in the negative Z-axis direction. The component unit continuum 10Ac in this modified example also has a sealing member 210 on the outer periphery of the positive electrode active material layer 120. In this modified example, connecting portion 12a, component unit 10e, connecting portion 12b, component unit 10f, and connecting portion 12c are arranged in a row (linearly) in the Y-axis direction.

As shown in FIG. 14B, the component unit continuum 10Ad in this modified example has a configuration in which a plurality of component units 10g and a plurality of component units 10h are alternately connected by connecting portions 13. Component unit 10g has a negative electrode active material layer 130 formed on the negative Z-axis surface of negative electrode metal layer 112, which is the negative electrode current collector foil of current collector foil 110, and component unit 10h has a negative electrode active material layer 130 formed on the positive Z-axis surface of negative electrode metal layer 112. The component unit continuum 10Ad in this modified example also has a sealing member 210 on the outer periphery of the negative electrode active material layer 130. In this modified example, connecting portion 13a, component unit 10g, connecting portion 13b, component unit 10h, and connecting portion 13c are arranged in a row (linearly).

In this configuration, as shown in Figures 15A and 15B, the process of stacking the component unit continuum 10Ac and 10Ad involves inserting the separator continuum 140A into the frame member 30. Then, component unit 10g of component unit continuum 10Ad is inserted into the frame member 30, and then component unit 10e of component unit continuum 10Ac is inserted into the frame member 30. At this time, the connection portions 12a and 12b connected to component unit 10e are inserted into a pair of openings 31a in a pair of side walls 31 of the frame member 30, and protrude from the pair of openings 31a on both sides in the Y-axis direction (positive and negative sides). Similarly, the connection portions 21a and 21b connected to the separator 140a are inserted into a pair of openings 32a in a pair of side walls 32 of the frame member 30, and protrude from the pair of openings 32a. In this modified example, a pair of openings are also formed in the pair of side walls 33 of the frame member 30, and the connection portions 13a and 13b connected to the component unit 10g of the component unit continuum 10Ad are inserted into the pair of openings in the pair of side walls 33 and protrude from the pair of openings.

As a result, the separator 140a, negative electrode active material layer 130, negative electrode metal layer 112, positive electrode metal layer 111, and positive electrode active material layer 120 are stacked in this order in the Z-axis direction. In other words, the current collecting foil 110 (positive electrode metal layer 111 and negative electrode metal layer 112) is arranged on the separator 140a between the positive electrode active material layer 120 and the negative electrode active material layer 130.

Next, as shown in Figure 16, in the process of stacking the component unit continuum 10Ac and 10Ad, separator 140b of separator continuum 140A is inserted into frame member 30. Then, component unit 10h of component unit continuum 10Ad is inserted into frame member 30, and then component unit 10f of component unit continuum 10Ac is inserted into frame member 30. Specifically, by bending connection portion 21b, separator continuum 140A is folded at the position of connection portion 21b, and separator 140b of separator continuum 140A is inserted into frame member 30, with connection portions 21b and 21c protruding from frame member 30. Then, by bending the connecting portion 13b, the component unit string 10Ad is folded at the position of the connecting portion 13b, and component unit 10h of the component unit string 10Ad is inserted into the frame member 30, with connecting portions 13b and 13c protruding from the frame member 30. Then, by bending the connecting portion 12b, the component unit string 10Ac is folded at the position of the connecting portion 12b, and component unit 10f of the component unit string 10Ac is inserted into the frame member 30, with connecting portions 12b and 12c protruding from the frame member 30.

As a result, separator 140a, component unit 10g, component unit 10e, separator 140b, component unit 10h, and component unit 10f are stacked in this order in the Z-axis direction. As described above, separator continuum 140A is folded at connection 21, component unit continuum 10Ad is folded at connection 13, and component unit continuum 10Ac is folded at connection 12 (combining component unit continuums 10Ac and 10Ad). This alternately stacks separators 140 and components in which current collector foil 110 is disposed between positive electrode active material layers 120 and negative electrode active material layers 130. After component unit continuums 10Ac and 10Ad are folded in this manner, current collector foil 110 is disposed between positive electrode active material layers 120 and negative electrode active material layers 130, which serve as active material layers.

As shown in Figure 17, after the separator continuous body 140A and the component unit continuous bodies 10Ac and 10Ad are folded and stacked, the connecting portions 12, 13, and 21 protruding from the frame member 30 are cut off. Details are the same as in the process for cutting off the connecting portions in the above embodiment. Subsequent processes are also the same as in the manufacturing method in the above embodiment.

(Variation 3)
In the above embodiment, an example of manufacturing a bipolar type electricity storage device will be described using a component unit 10 in which a positive electrode active material layer 120 is formed on the surface of the current collector foil 110 in the positive direction of the Z axis and a negative electrode active material layer 130 is formed on the surface in the negative direction of the Z axis, and a component unit continuum 10A in which the component unit is inverted upside down on the Z axis and joined at a connecting portion 12. FIG. 18 is a plan view showing the configuration of a component unit continuum 10Ae according to a third modification of this embodiment. FIG. 18 is a view corresponding to FIG. 5A. FIG. 19 is a cross-sectional view showing a step of separating the connecting portion 12 after stacking the component unit continuum 10Ae in the manufacturing method of an electricity storage device according to the third modification of this embodiment. FIG. 19 is a view corresponding to FIG. 12.

As shown in FIG. 18, the component unit continuum 10Ae in this modified example has a configuration in which a plurality of component units 10i and a plurality of component units 10j are alternately connected by connecting portions 12. Like the component unit 10 in the above embodiment, the component unit 10i has a positive electrode active material layer 120 formed on the surface of the current collector foil 110 facing in the positive Z-axis direction, and a negative electrode active material layer 130 formed on the surface facing in the negative Z-axis direction. The component unit 10j has a negative electrode active material layer 130 formed on the surface of the current collector foil 110 facing in the positive Z-axis direction, and a positive electrode active material layer 120 formed on the surface facing in the negative Z-axis direction. The remaining configuration of this modified example is the same as that of the above embodiment, so detailed description will be omitted.

In this configuration, as shown in FIG. 19, by alternately folding the component unit continuous body 10Ae and the separator continuous body 140A, the separator 140 can be placed between the component unit 10i and the component unit 10j. This results in the current collector foil 110, positive electrode active material layer 120, negative electrode active material layer 130, and separator 140 being stacked in the same stacking order as in the above embodiment. Thereafter, the connecting portions 12 and 21 protruding from the frame member 30 are cut off. These details and subsequent processing are the same as in the manufacturing method in the above embodiment.

(Variation 4)
In the above embodiment, the object is to manufacture a bipolar structure as the energy storage device 1, but the present invention is not limited thereto, and a monopolar structure can also be formed. Fig. 20A is a plan view showing the configuration of a component unit continuum 10Af according to Modification 4 of the present embodiment, and Fig. 20B is a plan view showing the configuration of a component unit continuum 10Ag according to Modification 4 of the present embodiment. Figs. 20A and 20B are views corresponding to Fig. 5A. Fig. 21 is a cross-sectional view showing a step of cutting off the connection portions 12, 13 after folding the component unit continuums 10Af and 10Ag in the manufacturing method of the energy storage device according to Modification 4 of the present embodiment. Fig. 21 is a view corresponding to Fig. 12.

As shown in Figure 20A, the component unit continuum 10Af in this modified example has a configuration in which multiple component units 10k are connected by connecting portions 12. Each component unit 10k has a positive electrode active material layer 120 formed on both sides in the Z-axis direction of a positive electrode metal layer 111, which is the positive electrode current collector foil of a current collector foil 110.

As shown in Figure 20B, the component unit continuum 10Ag in this modified example has a configuration in which multiple component units 10l are connected by connecting portions 13. The component unit 10l has a negative electrode active material layer 130 formed on both sides in the Z-axis direction of the negative electrode metal layer 112, which is the negative electrode current collector foil of the current collector foil 110.

In this configuration, as shown in FIG. 21 , the component unit continuum 10Af, the component unit continuum 10Ag, and the separator continuum 140A are alternately folded to place a separator 140 between the component unit 10k and the component unit 10l. As a result, the component unit 10k, in which the positive electrode active material layer 120 is formed on both sides of the positive electrode metal layer 111, and the component unit 10l, in which the negative electrode active material layer 130 is formed on both sides of the negative electrode metal layer 112, are stacked via the separator 140. The connection portions 12, 13, and 21 protruding from the frame member 30 are then cut off. The portion of the connection portion 12 remaining on the positive electrode metal layer 111 and the portion of the connection portion 13 remaining on the negative electrode metal layer 112 can be used as tabs. In this case, the connection portions 12 and 13 may be cut off so that longer portions of the connection portions 12 and 13 remain on the positive electrode metal layer 111 and the negative electrode metal layer 112. By connecting the electrode stacks constructed in this modified example in parallel with tabs, a monopolar structure can be formed, rather than the bipolar structure described in the previous examples.

(Other Modifications)
In the above embodiment, the component unit continuum 10A and the separator continuum 140A are arranged as the component unit continuum, but this is not limited to this. The component unit continuum 10A may not be arranged, and a single component unit 10 may be arranged, or the separator continuum 140A may not be arranged, and a single separator 140 may be arranged. The same applies to other component unit continuums. In other words, it is sufficient that at least one component unit continuum is arranged.

In the above embodiment, the number of sides of the current collector foil 110 may be odd rather than even, and the current collector foil 110 may be triangular, pentagonal, etc. in plan view. The same applies to the intermediate foil 11, separator 140, etc. In other words, the shape of the energy storage device 1 in plan view may be any shape, such as an even polygon, odd polygon, or circle.

In the above embodiment, a connection portion 12 with a width shorter than the length of one side of the current collecting foil 110 is connected to that side, but a connection portion 12 with a width equal to or longer than the length of that side may also be connected. The same applies to the separator 140, etc.

In the above embodiment, the component unit string 10A is folded by inserting the current collecting foil 110 and the like into the frame member 30, but the component unit string 10A may also be folded without inserting the current collecting foil 110 and the like into the frame member 30. The same applies to the separator 140 and the like.

In the above embodiment, the connection portions 12 protruding from the frame member 30 are cut off, but the connection portions 12 may also be cut off within the frame member 30. The same applies to the separators 140, etc.

In the above embodiment, the positive electrode active material layer 120 and the negative electrode active material layer 130 may be interchanged. In this case, the negative electrode active material layer 130 may be disposed within the through-hole of the intermediate foil 11.

In the above embodiment, the separator continuum 140A is folded together with the component unit continuum 10A, but the separator 140 may be attached to the negative electrode active material layer 130 or the positive electrode active material layer 120 by adhesive or the like, and then the component unit continuum 10A may be folded. In this case, the steps of folding the separator continuum 140A and cutting off the connection portions 21 can be omitted.

In the above embodiment, a solid electrolyte layer may be disposed in place of the separator 140. Any known solid electrolyte may be used as the solid electrolyte layer.

In the above embodiment, the energy storage device 1 may be used in an energy storage pack 1A as shown in FIG. 22. FIG. 22 is a plan view showing the configuration of the energy storage pack 1A. As shown in FIG. 22, the energy storage pack 1A includes multiple energy storage devices 1. Because the energy storage device 1 has a regular hexagonal shape in a plan view, six energy storage devices 1 can be arranged around one energy storage device 1 in a plan view. The multiple energy storage devices 1 are connected in series or in parallel. The energy storage pack 1A also includes a metal case, resin case, or the like that houses the multiple energy storage devices 1, but this is not shown in the figures. The technology of the present invention may be applied to at least one energy storage device 1 included in the energy storage pack 1A.

23 。 The energy storage device 1 may be used in an energy storage pack 1B as shown in FIG. 23. FIG. 23 is a cross-sectional view showing the configuration of the energy storage pack 1B. The internal configuration of the energy storage device 1 is omitted from FIG. 23. As shown in FIG. 23, the energy storage pack 1B includes an energy storage device stack 2 in which multiple energy storage devices 1 are stacked, and a conductive member 3. In this case, the technology of the present invention only needs to be applied to at least one energy storage device 1 included in the energy storage pack 1B. Two adjacent energy storage devices 1 in the energy storage device stack 2 are electrically connected by contact or bonding (welding, etc.). The conductive member 3 is made of a metal such as stainless steel, and the energy storage device 1 located at the end in the stacking direction (Z-axis direction) and the conductive member 3 are electrically connected by contact or bonding (welding, etc.). An adhesive may be used for bonding. The multiple energy storage devices 1 in the energy storage device stack 2 are connected in series, and charging and discharging are performed via the conductive member 3. The electricity storage pack 1B may be restrained in the stacking direction (Z-axis direction) using restraining members such as screws, resin bands, or metal bands. The electricity storage device stack 2 and conductive member 3 may be housed in a metal or resin case.

As another example of an electricity storage pack 1B, Figure 24 shows a configuration in which individual electricity storage devices 1 are housed in an exterior housing 4. Figure 24 is a cross-sectional view showing the configuration of an electricity storage pack 1C. As shown in Figure 24, the electricity storage device 1 of this configuration has a connection portion 5 exposed from the exterior housing 4. A laminate film or the like can be used as the exterior housing 4. The connection portions 5 of adjacent electricity storage devices 1 are electrically connected by contact or bonding (welding, etc.). The connection portion 5 of the electricity storage device 1 located at the end in the stacking direction (Z-axis direction) and the conductive member 3 are electrically connected by contact or bonding (welding, etc.). The rest of the configuration is the same as that of the above-mentioned electricity storage pack 1B, so description will be omitted.

Configurations constructed by any combination of the components included in the above embodiments and their variations are also within the scope of the present invention.

The present invention can be applied to manufacturing methods for power storage devices such as bipolar batteries.

REFERENCE SIGNS LIST 1 Energy storage device 1A, 1B, 1C Energy storage pack 2 Energy storage device laminate 3 Conductive member 4 Exterior body 5 Connection portion 10, 10a, 10b, 10c, 10d, 10e, 10f, 10g, 10h, 10i, 10j, 10k, 10l Member unit (electrode member unit)
10A, 10Aa, 10Ab, 10Ac, 10Ad, 10Ae, 10Af, 10Ag Component unit continuum 11, 11a, 11b, 11c, 11d Intermediate foil 11a1, 11b1, 11c1, 11d1 Through hole 12, 12a, 12b, 12c, 12d, 13, 13a, 13b, 13c, 21, 21a, 21b, 21c Connection portion 30 Frame member 31, 32, 33 Side wall 31a, 32a Opening 34 Bottom wall 100 Electrode unit 101, 102 End unit 110 Current collecting foil 111 Positive electrode metal layer (metal layer)
112 Negative electrode metal layer (metal layer)
120 Positive electrode active material layer 130 Negative electrode active material layer 140, 140a, 140b Separator 140A Separator continuous body 200 Peripheral sealing member 210 Sealing member 300 End member 400 Laminate

Claims (5)

A method for manufacturing an electricity storage device including a plurality of component units stacked in a stacking direction,
Arranging a member unit continuum in which a plurality of the member units are connected by connecting portions;
folding the continuous member unit body at the position of the connecting portion;
After folding the member unit continuous body, the connecting portion is removed;
A method for manufacturing an electricity storage device comprising: The method for manufacturing an electricity storage device according to claim 1 , wherein at least a portion of the member unit continuum has a positive electrode active material layer disposed on one surface of a current collector foil and a negative electrode active material layer disposed on the other surface of the current collector foil. The method for manufacturing an energy storage device according to claim 1 or 2, wherein the component unit continuum is made up of a plurality of polygonal or circular component units each having an even number of sides of four or more when viewed from the stacking direction, connected together at the connection portions. The method for manufacturing an electricity storage device according to claim 1 or 2, wherein the member unit continuum is polygonal when viewed from the stacking direction, and the width of the connection portion is shorter than the length of one side of the polygon. When folding the member unit continuous body, the member units are inserted into a frame member, and the connecting portions are folded to project from the frame member;
The method for manufacturing an electricity storage device according to claim 1 or 2, wherein when the connecting portion is removed, the connecting portion protruding from the frame member is cut off.