JP7466263B2 - Battery packaging and battery - Google Patents

Description

The present invention relates to a battery packaging body and a battery.

A conventional battery packaging body is disclosed in Patent Document 1. This battery packaging body is composed of a laminate including at least a barrier layer made of metal foil and a heat-sealable resin layer made of a heat-adhesive resin arranged as the innermost layer.

The battery packaging has a main body and a lid that are overlapped by folding the laminate. The main body and the lid have a storage section with an opening on the opposing surface to store the battery element, and a flange extending outward from the periphery of the opening. The storage section is formed by press molding (drawing) the laminate.

The battery element stored in the storage section of the main body is covered with the storage section of the lid, and the flanges of the main body and lid are thermally bonded together. This seals the battery element inside the battery packaging.

JP 2001-229888 A (page 4, Figure 3)

However, with the above-mentioned conventional battery packaging, the laminate stretches when the storage section is formed by press molding, and part of the barrier layer may become thin or the barrier layer may crack. This causes a problem of reduced yield of the battery packaging. On the other hand, increasing the radius of curvature of each corner of the press molding die can prevent the barrier layer from becoming thin and cracking, but this causes a problem of reduced volume efficiency of the battery packaging.

In view of the above problems, the present invention aims to provide a battery packaging body that can improve yield and volume efficiency, and a battery using the same.

To achieve the above object, the present invention provides a battery packaging body that is composed of a laminate including at least a barrier layer and a heat-sealable resin layer disposed on the innermost layer, includes a main body having an opening on the top surface for housing a battery element, and a lid that closes the opening, the main body having a rectangular bottom plate, side plates that are bent from the four sides of the bottom plate and stand upright, a first connecting portion that connects adjacent side plates, and a flange plate that is bent outward from the upper ends of the four side plates, the lid has an outer periphery bonded to the flange plate, and the first connecting portion is bonded by folding in half at a first fold line that extends from a corner of the bottom plate at an incline outward toward the top, on the side of the heat-sealable resin layer.

The present invention is also characterized in that, in the battery packaging body having the above-mentioned configuration, second connecting parts are provided at both ends of the flange plate, which are connected to the upper ends of the first connecting parts via second fold lines that fold the heat-sealable resin layer side in a mountain or valley manner, and the second connecting parts are overlapped with the adjacent second connecting parts or the adjacent flange plates, and the lid part is adhered onto the second connecting parts.

In addition, in the battery packaging of the present invention having the above-mentioned configuration, it is preferable that the end of the flange plate is folded back and adhered at an angle by a valley fold or a mountain fold on the heat-sealable resin layer side, and the second connecting portion adjacent to the end of the flange plate is arranged to overlap.

In addition, in the battery packaging of the present invention having the above-mentioned configuration, it is preferable that one of the adjacent second connecting parts is folded in half by a mountain fold on the heat-sealable resin layer side and adhered onto the other second connecting part.

In addition, in the battery packaging of the present invention having the above configuration, it is preferable that the upper end of the first fold line is disposed at the same height as the upper end of the side panel.

In addition, in the battery packaging of the present invention having the above configuration, it is preferable that the first fold line is inclined at 45° to the vertical direction.

Furthermore, in the present invention, in the battery packaging body having the above configuration, it is preferable that the ratio of the thickness of the barrier layer at the intermediate position in the height direction of the side panel to the thickness of the barrier layer at the joint between the side panel and the bottom panel is 100±10% or less.

The battery of the present invention is characterized in that a battery element having at least a positive electrode, a negative electrode, and an electrolyte is housed in the main body of the battery packaging body having the above-mentioned configurations.

The battery of the present invention is also characterized in that an electronic element having at least a positive electrode and a negative electrode and integrated with a solid electrolyte is housed within the main body of the battery packaging body having the above-mentioned configurations.

In addition, in the battery of the present invention having the above configuration, it is preferable that the metal tabs of the positive and negative electrodes protrude from between the flange plate and the lid portion, and the flange plate from which the metal tabs do not protrude is bent downward.

According to the present invention, the main body of the battery packaging has a rectangular bottom panel, side panels, and flange panel, and the outer periphery of the lid is bonded onto the flange panel. In addition, the first connecting portion connecting the adjacent side panels is folded in half at the inclined first fold line and bonded. This prevents a decrease in the barrier properties of the gap between the adjacent side panels, and allows the battery packaging to be formed by folding the laminate. Therefore, the yield and volume efficiency of the battery packaging can be improved.

1 is a perspective view of a battery according to a first embodiment of the present invention; 1 is a perspective view of a battery packaging for a battery according to a first embodiment of the present invention; 1 is a development view showing a main body of a battery packaging for a battery according to a first embodiment of the present invention; 1 is a cross-sectional view showing a layer structure of a battery packaging body for a battery according to a first embodiment of the present invention. FIG. 4 is a development view showing a modified example of the main body of the battery packaging for the battery according to the first embodiment of the present invention. FIG. 4 is a development view showing a modified example of the main body of the battery packaging for the battery according to the first embodiment of the present invention. FIG. 6 is a development view showing a main body of a battery packaging for a battery according to a second embodiment of the present invention. FIG. 11 is a development view showing a main body of a battery packaging for a battery according to a third embodiment of the present invention. FIG. 13 is a development view showing a modified example of the main body of the battery packaging for the battery according to the third embodiment of the present invention. FIG. 11 is a development view showing a main body of a battery packaging for a battery according to a fourth embodiment of the present invention. FIG. 13 is a development view showing a main body of a battery packaging for a battery according to a fifth embodiment of the present invention. FIG. 13 is a development view showing a main body of a battery packaging for a battery according to a sixth embodiment of the present invention. FIG. 13 is a development view showing a main body of a battery packaging for a battery according to a seventh embodiment of the present invention. FIG. 2 is a top view of a battery packaging body for a battery according to an embodiment of the present invention. Cross-sectional view taken along line XX in FIG. 14 .

First Embodiment
A first embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a perspective view of a battery 1 according to the first embodiment, and Fig. 2 is a perspective view of a battery packaging 10 for the battery 1 according to the first embodiment.

Battery 1 includes a battery element 40 sealed and housed inside a battery packaging body (hereinafter, abbreviated as packaging body) 10. Battery 1 may be used as either a primary battery or a secondary battery, but a secondary battery is more preferable. The type of secondary battery is not particularly limited, and examples include lithium ion batteries, lithium ion polymer batteries, lead storage batteries, nickel hydrogen storage batteries, nickel cadmium storage batteries, nickel iron storage batteries, nickel zinc storage batteries, silver oxide zinc storage batteries, metal air batteries, polyvalent cation batteries, condensers, and capacitors. Among these secondary batteries, lithium ion batteries and lithium ion polymer batteries are suitable applications for battery 1 of this embodiment.

The battery element 40 has a positive electrode metal tab 41a and a negative electrode metal tab 41b that protrude from the packaging body 10. The metal tabs 41a and 41b are sandwiched and adhered between a flange plate 23c and a lid portion 30 (described later) while protruding outside the packaging body 10. In addition, when the electrolyte is liquid, the electrolyte is filled inside the packaging body 10 separately from the battery element 40, and when the electrolyte is solid, the solid electrolyte is integrated with the battery element 40.

In FIG. 1, the metal tabs 41a and 41b protrude in the same direction, but the metal tabs 41a and 41b do not have to protrude in the same direction. For example, the metal tab 41a may protrude from the flange plate 23c side, and the metal tab 41b may protrude from the flange plate 23a side.

The package 10 is formed by folding the package material 100 (see FIG. 4) made of a laminated body described below into a box shape. The package 10 has a main body 20 that houses the battery element 40 and a lid 30 that covers the main body 20.

The main body 20 is tray-shaped, with rectangular side panels 22a to 22d standing up from the four sides of a rectangular bottom panel 21, and an opening 20a on the top surface. In addition, rectangular flange panels 23a to 23d that are bent outward are connected to the upper ends of the side panels 22a to 22d on the four sides.

The lid 30 is in the form of a rectangular sheet, and the outer periphery of the lid 30 is brought into contact with the flange plates 23a to 23d and thermally bonded using a thermal adhesive layer (thermally adhesive resin layer) 103 (see FIG. 4) described below. This causes the periphery of the opening 20a to be sealed by the lid 30.

Furthermore, adjacent side panels 22a to 22d are connected by connecting parts (first connecting parts) 24a to 24d (see FIG. 3) that are folded in half and thermally bonded on the inside. Both ends of flange panels 23a to 23d are provided with connecting parts (second connecting parts) 26a to 26h that are connected to connecting parts (first connecting parts) 24a to 24d (see FIG. 3). Connecting parts 26a, 26d, 26e, and 26h are overlappingly arranged on both ends of flange panels 23a and 23c, respectively.

Figure 3 is an exploded view showing the main body 20 of the package 10. The main body 20 is formed by folding a sheet-like packaging material 100, and the packaging material 100 has valley fold lines 11 shown by dashed lines and mountain fold lines 12 shown by dashed lines at predetermined positions. The valley fold lines 11 are valley folded on the side of the thermal adhesive layer 103 (see Figure 4) on the inner surface, and the mountain fold lines 12 are mountain folded on the side of the thermal adhesive layer 103 (see Figure 4) on the inner surface.

Rectangular side panels 22a to 22d are connected to the four sides of the rectangular bottom panel 21 via valley fold lines 11. Rectangular flange panels 23a to 23d are connected to the upper edges of the side panels 22a to 22d via mountain fold lines 12.

The sides of adjacent side panels 22a to 22d are connected via square connecting parts (first connecting parts) 24a to 24d, respectively, indicated by dashed hatching. Note that connecting part 24a is connected to side panel 22a via mountain fold line 12, and is connected to side panel 22b without a fold line.

Similarly, the connecting portion 24b is connected to the side panel 22c via the mountain fold line 12, and is connected to the side panel 22b without a fold line. The connecting portion 24c is connected to the side panel 22c via the mountain fold line 12, and is connected to the side panel 22d without a fold line. The connecting portion 24d is connected to the side panel 22a via the mountain fold line 12, and is connected to the side panel 22d without a fold line.

The connecting portions 24a to 24d have valley fold lines (first fold lines) 11 that cross the connecting portions 24a to 24d in a line-symmetrical manner from the corners of the bottom panel 21. These valley fold lines 11 are inclined at 45 degrees to each side of the bottom panel 21. In other words, when the bottom panel 21 is placed on a horizontal surface, they are inclined at 45 degrees to the vertical direction.

At this time, the valley fold lines 11 on the connecting parts 24a to 24d are formed to extend to the extension of the mountain fold lines 12 between the side panels 22a to 22d and the flange panels 23a to 23d. As a result, when the side panels 22a to 22d are erected, the upper ends of the valley fold lines 11 on the connecting parts 24a to 24d are positioned at the same height as the side panels 22a to 22d.

Square connecting parts (second connecting parts) 26a to 26h, indicated by dotted hatching, are provided at both ends of the flange plates 23a to 23d. The connecting parts 26a to 26h connect the flange plates 23a to 23d and the connecting parts 24a to 24d. The connecting part 26a is connected to the flange plate 23a and the connecting part 24a via a mountain fold line (second fold line) 12.

Similarly, the connecting portion 26d is connected to the flange plate 23c and the connecting portion 24b via a mountain fold line (second fold line) 12. The connecting portion 26e is connected to the flange plate 23c and the connecting portion 24c via a mountain fold line (second fold line) 12. The connecting portion 26h is connected to the flange plate 23a and the connecting portion 24d via a mountain fold line (second fold line) 12.

The connecting portion 26b is connected to the flange plate 23b without a fold line, and is connected to the connecting portion 24a via a mountain fold line (second fold line) 12. Similarly, the connecting portion 26c is connected to the flange plate 23b without a fold line, and is connected to the connecting portion 24b via a mountain fold line (second fold line) 12. The connecting portion 26f is connected to the flange plate 23d without a fold line, and is connected to the connecting portion 24c via a mountain fold line (second fold line) 12. The connecting portion 26g is connected to the flange plate 23d without a fold line, and is connected to the connecting portion 24d via a mountain fold line (second fold line) 12. In other words, the connecting portions 24a to 24d and the connecting portions 26a to 26h are connected to each other via the mountain fold line (second fold line) 12.

A pair of valley fold lines 11 are formed on both sides of the flange plates 23a, 23c, extending from the corners of the side plates 22a, 22c in a direction approaching each other and crossing the flange plates 23a, 23c diagonally. These valley fold lines 11 are inclined at 45° with respect to the mountain fold lines (second fold lines) connecting the connecting parts 26a, 26d, 26e, 26f to the connecting parts 24a to 24d.

The width W1 of the side panels 22a to 22d (the depth when the packaging body 10 is assembled) is formed to be the same as the width W2 of the flange panels 23a to 23d. As a result, when the packaging body 10 is assembled, the upper ends of the valley fold lines 11 on the connecting portions 24a to 24d are positioned at the same height as the side panels 22a to 22d. Note that the width W1 of the side panels 22a to 22d may be formed to be smaller than the width W2 of the flange panels 23a to 23d.

Figure 4 is a cross-sectional view showing the layer structure of the packaging material 100. The packaging material 100 is made of a laminate in which a base layer 101, a barrier layer 102, and a thermal adhesive layer 103 are laminated in this order. The base layer 101 and the barrier layer 102 are bonded via an adhesive layer 104. The barrier layer 102 and the thermal adhesive layer 103 are bonded via an adhesive layer 105.

The thickness of the packaging material 100 is not particularly limited, but from the viewpoint of strength, it can be 50 μm or more. Furthermore, from the viewpoint of moldability and miniaturization of the battery 1, it is desirable for the packaging material 100 to be thin, and the thickness of the packaging material 100 can be, for example, 200 μm or less. The thickness of the packaging material 100 can be preferably 150 μm or less, more preferably 100 μm or less, and even more preferably 80 μm or less.

It is preferable that a lubricant is disposed on the surfaces of the base layer 101 and the thermal adhesive layer 103. The lubricant may be applied to the surfaces of the base layer 101 and the thermal adhesive layer 103. In addition to applying the lubricant, the lubricant may be contained in the resin constituting the base layer 101 or the thermal adhesive layer 103 and heated to bleed out the lubricant onto the surfaces of the base layer 101 and the thermal adhesive layer 103. The type of lubricant is not particularly limited, but an amide-based lubricant is preferable.

The base material layer 101 is disposed on the outer surface side of the packaging body 10 and has insulating properties. Examples of materials that form the base material layer 101 include polyester, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, silicone resin, phenolic resin, polyetherimide, polyimide, polycarbonate, and mixtures and copolymers thereof. Among these, it is preferable that the base material layer 101 includes a layer formed of polyester or polyamide.

The substrate layer 101 may be formed from a resin film, or may be formed by coating the barrier layer 102 with the above-mentioned material. When the substrate layer 101 is formed from a resin film, a uniaxially oriented film is preferable, and a biaxially oriented film is more preferable. Stretched films have improved heat resistance due to oriented crystallization, and are therefore preferably used as the substrate layer 101. For this reason, biaxially oriented nylon films and biaxially oriented polyester films can be preferably used, and in particular, biaxially oriented polyethylene terephthalate films can be more preferably used.

In addition, the base layer 101 may be made of multiple resin films of different materials laminated together (multi-layer structure) to improve pinhole resistance and insulation. Specific examples include a multi-layer structure in which a polyester film and a nylon film are laminated together, a multi-layer structure in which multiple nylon films are laminated together, and a multi-layer structure in which multiple polyester films are laminated together.

When the base layer 1 has a multilayer structure, a laminate of a biaxially oriented nylon film and a biaxially oriented polyester film, a laminate of multiple biaxially oriented nylon films, or a laminate of multiple biaxially oriented polyester films is preferred.

For example, when the base layer 1 is formed from a two-layer resin film, it is preferable to have a laminated structure of polyester resin and polyester resin, a laminated structure of polyamide resin and polyamide resin, or a laminated structure of polyester resin and polyamide resin.

More preferably, the laminate is made of polyethylene terephthalate and polyethylene terephthalate, nylon and nylon, or polyethylene terephthalate and nylon.

In addition, since polyester resin is less likely to discolor when an electrolyte solution adheres to the surface, it is preferable to laminate the base material layer 1 so that the polyester resin is located in the outermost layer in this laminated structure. When the base material layer 1 has a multi-layer structure, the thickness of each layer is preferably about 2 to 25 μm. Also, the film may be coated with resins of different materials.

The thickness of the base layer 101 is, for example, 4 μm or more in order to improve the shape stability while reducing the thickness of the package 10. The thickness of the base layer 101 can be preferably 10 μm or more and 75 μm or less, more preferably 10 μm or more and 50 μm or less.

The adhesive layer 104 is preferably made of a two-component curing adhesive or a one-component curing adhesive. There are no particular limitations on the adhesive, and it may be any of a chemical reaction type, a solvent volatilization type, a thermal melting type, a thermal pressure type, etc.

Specific examples of adhesive components that can be used to form the adhesive layer 104 include polyester resins, polyether adhesives, polyurethane adhesives, epoxy resins, phenolic resins, polyamide resins, polyolefin resins, polyvinyl acetate resins, cellulose adhesives, (meth)acrylic resins, polyimide resins, urea resins, amino resins, silicone resins, polycarbonates, and rubbers. These adhesive components may be used alone or in combination of two or more. Among these adhesive components, polyurethane adhesives are more preferred. In addition, pigments such as graphite and metal oxides, and additives described below may be added to the adhesive layer 104.

The thickness of the adhesive layer 104 is not particularly limited as long as it functions as an adhesive layer, but can be, for example, 1 μm or more and 10 μm or less, preferably 2 μm or more and 5 μm or less.

The barrier layer 102 is a layer that not only improves the strength of the package 10, but also has the function of preventing water vapor, oxygen, light, etc. from penetrating into the inside of the battery 1. The barrier layer 102 is formed from a metal foil such as aluminum, an aluminum alloy, stainless steel, or titanium, and aluminum alloy foil or stainless steel foil is particularly preferred.

Examples of stainless steel foil include austenitic stainless steel foil and ferritic stainless steel foil. It is preferable that the stainless steel foil is made of austenitic stainless steel.

Specific examples of austenitic stainless steels that make up the stainless steel foil include SUS304, SUS301, and SUS316L, with SUS304 being particularly preferred.

There are no particular limitations on the thickness of the stainless steel foil, but preferred upper limits include 85 μm or less, 50 μm or less, 40 μm or less, and 25 μm or less. Preferred ranges include approximately 10 to 85 μm, approximately 10 to 50 μm, and approximately 15 to 25 μm.

In addition, to prevent wrinkles or pinholes from occurring in the barrier layer 102 during the manufacturing of the packaging material 100, it may be formed, for example, from annealed soft aluminum alloy foil.

The thickness of the barrier layer 102 is not particularly limited as long as it exhibits water vapor barrier properties, but can be, for example, 10 μm to 100 μm, preferably 10 μm to 55 μm, and more preferably 10 μm to 38 μm.

In order to stabilize the adhesion of the barrier layer 102 and to prevent dissolution or corrosion, it is preferable that at least one side, and preferably both sides, are provided with a base coating layer. The base coating layer is formed, for example, by subjecting the surface of the barrier layer 102 to a chemical conversion treatment.

Examples of chemical conversion treatments include chromate treatment and phosphate chromate treatment. The undercoat layer can also be formed by coating a material in which fine particles of metal oxides such as aluminum oxide, titanium oxide, cerium oxide, and tin oxide, or barium sulfate are dispersed in phosphoric acid, and baking is performed at 150°C or higher. A resin layer in which a cationic polymer is crosslinked with a crosslinking agent may be further formed on the corrosion-resistant undercoat layer. When a undercoat layer is formed on the surface of the barrier layer 102 of the present invention, the barrier layer 102 includes the undercoat layer.

The barrier layer 102 can also distinguish between the MD (machine direction) and TD (transverse direction) in the manufacturing process. For example, when the barrier layer 102 is made of aluminum alloy foil, linear lines known as rolling marks are formed on the surface of the aluminum alloy foil in the rolling direction (RD: Rolling Direction) of the aluminum alloy foil. Since the rolling marks extend along the rolling direction, the rolling direction of the aluminum alloy foil can be ascertained by observing the surface of the aluminum alloy foil.

In addition, during the manufacturing process of the packaging material 100, the MD of the laminate and the RD of the aluminum alloy foil usually coincide, so the MD of the laminate can be identified by observing the surface of the aluminum alloy foil of the laminate and identifying the rolling direction (RD) of the aluminum alloy foil. In addition, the TD of the laminate is perpendicular to the MD of the laminate, so the TD of the laminate can also be identified.

The thermal adhesive layer 103 is disposed on the innermost layer, and the thermal adhesive layers 103 are thermally fused together when the package 10 is assembled. There are no particular limitations on the resin components used in the thermal adhesive layer 103 as long as they are thermally fused, but examples include polyolefins, cyclic polyolefins, carboxylic acid-modified polyolefins, and carboxylic acid-modified cyclic polyolefins.

The thermal adhesive layer 103 may be formed of one type of resin component alone, or may be formed of a blend polymer combining two or more types of resin components. Furthermore, the thermal adhesive layer 103 may be formed of only one layer, or may be formed of two or more layers using the same or different resin components.

The thickness of the thermal adhesive layer 103 is not particularly limited as long as it exhibits thermal fusion properties, but it is preferably about 100 μm or less, more preferably 80 μm or less, and even more preferably 60 μm or less.

The adhesive layer 105 can be made of the same adhesive as the adhesive layer 104. The adhesive layer 105 can also be made of polyolefin resins such as the polyolefin, cyclic polyolefin, carboxylic acid-modified polyolefin, and carboxylic acid-modified cyclic polyolefin exemplified for the thermal adhesive layer 103. From the viewpoint of excellent adhesion between the barrier layer 102 and the thermal adhesive layer 103, carboxylic acid-modified polyolefins are preferred, and carboxylic acid-modified polypropylene is particularly preferred.

In order to reduce the thickness of the packaging body 10 while improving the shape stability, the adhesive layer 105 is preferably made of a resin composition containing an acid-modified polyolefin and a curing agent. Examples of acid-modified polyolefins include carboxylic acid-modified polyolefins and carboxylic acid-modified cyclic polyolefins. The curing agent is not particularly limited, but examples include epoxy-based curing agents, polyfunctional isocyanate-based curing agents, carbodiimide-based curing agents, and oxazoline-based curing agents.

The preferred range of thickness for adhesive layer 105 is 2 μm or more and 50 μm or less. If an adhesive such as that exemplified for adhesive layer 104 is used, the thickness can be preferably 2 μm or more and 10 μm or less, more preferably 2 μm or more and 5 μm or less. If a resin such as that exemplified for thermal adhesive layer 103 is used, the thickness can be preferably 2 μm or more and 50 μm or less, more preferably 10 μm or more and 40 μm or less.

A surface coating layer (not shown) may be provided on the upper surface of the base material layer 101 (the surface of the base material layer 101 opposite the barrier layer 102) for the purpose of improving design, electrolyte resistance, abrasion resistance, formability, etc. The surface coating layer is the layer located at the outermost layer when the battery 1 is assembled, and when a surface coating layer is provided, a lubricant may be disposed on the surface of the surface coating layer.

The surface coating layer can be formed from, for example, polyvinylidene chloride, polyester resin, urethane resin, acrylic resin, epoxy resin, etc. Also, from the viewpoint of further increasing the electrolyte resistance of the surface of the packaging body 10, the surface coating layer may be formed from a mixed resin combining urethane resin and acrylic resin, etc. Among these, it is preferable to form the surface coating layer from a two-component curing resin. Examples of the two-component curing resin that forms the surface coating layer include a two-component curing urethane resin, a two-component curing polyester resin, and a two-component curing epoxy resin.

The surface coating layer may also contain additives. Examples of additives include fine particles having a particle size of 0.5 nm to 5 μm. The material of the additive is not particularly limited, but examples of the additive include metals, metal oxides, inorganic substances, and organic substances. The shape of the additive is also not particularly limited, but examples of the additive include spherical, fibrous, plate-like, amorphous, and balloon-like. Pigments such as graphite and metal oxides may also be added to the surface coating layer. For example, a matting agent that forms irregularities on the surface of the surface coating layer may also be added to the surface coating layer. In this case, the surface coating layer having an irregular surface can function as a matting layer. The additives shown above can be used as the matting agent.

The packaging material 100 is formed, for example, by punching a roll-shaped laminate into a predetermined shape by a punching process. At this time, it is preferable that the valley fold lines 11 and mountain fold lines 12 are formed by creasing. The valley fold lines 11 are formed by creasing pressed from the thermal adhesive layer 103 side of the packaging material 100. The mountain fold lines 12 are formed by creasing pressed from the base layer 101 side of the packaging material 100. By providing the creasing, the packaging material 100 can be reliably folded along the valley fold lines 11 and mountain fold lines 12.

The main body 20 of the package 10 is formed by folding the packaging material 100 with the above-mentioned configuration at the valley fold line 11 and the mountain fold line 12. That is, the side panels 22a to 22d are valley folded from the periphery of the bottom panel 21 and erected. At this time, the connecting portions 24a to 24d are folded in half on the valley fold line 11 (first fold line) and thermally bonded by the thermal adhesive layer 103 on the inner surface. As a result, the folded connecting portions 24a and 24b are arranged along the side panel 22b, and the folded connecting portions 24c and 24d are arranged along the side panel 22d.

Next, the flange plates 23a to 23d are mountain-folded from the upper ends of the side panels 22a to 22d, and the connecting portions 26a to 26h are mountain-folded from the upper ends of the connecting portions 24a to 24d.

The connecting portions 26a, 26d, 26e, and 26h are mountain-folded from both side ends of the flange plates 23a and 23c, respectively, and both side portions of the flange plates 23a and 23c are folded back at an angle on the valley fold lines 11 and thermally bonded by the thermal adhesive layer 103 on the inner surface.

As a result, the connecting portions 26a and 26h overlap both sides of the flange plate 23a, and the connecting portions 26d and 26e overlap both sides of the flange plate 23c. As a result, an annular flange F (see Figure 2) is formed around the opening 20a, with the flange plates 23a to 23d and the connecting portions 26a to 26h connected to each other.

Next, the battery element 40 is stored in the main body 20. At this time, for example, the metal tabs 41a, 41b are arranged on the flange plate 23c. When the battery element 40 is stored, the lid 30 is placed on the flange plates 23a to 23d, and the outer periphery of the lid 30 and the flange plates 23a to 23d are thermally bonded by the thermal adhesive layer 103, leaving some unsealed areas. Then, after the electrolyte is injected from the unsealed areas, the unsealed areas are thermally bonded by the thermal adhesive layer 103, and the battery 1 is formed. At this time, the lid 30 of the battery 1 is placed above the bottom plate 21 when the bottom plate 21 is placed on a horizontal surface.

The above-mentioned method of injecting the electrolyte is an example, and is not limited to this method. For example, one side of the flange plate 23c may be left as an unsealed portion. In this case, the other three sides of the flange plates 23a, 23b, and 23d are heat-sealed, and after the electrolyte is injected from the unsealed portion, one side of the flange plate 23c in the unsealed portion is heat-sealed.

Because the main body 20 of the packaging body 10 is formed by folding the packaging material 100, it is possible to prevent the barrier layer 102 from becoming thin and cracking. In addition, it is possible to reduce the radius of curvature when folding the side panels and flange panels. Therefore, it is possible to improve the yield and volume efficiency of the packaging body 10.

In addition, when the thickness of the barrier layer 102 at the midpoint of the height (depth) of the side panels 22a to 22d is B, and the thickness of the barrier layer 102 at the joint between the side panels 22a to 22d and the bottom panel 21 is C, the ratio (%) of the thickness of B to C, calculated as (B/C) x 100, is 100±10% or less, so that the thickness of the barrier layer 102 is approximately uniform in the height direction, preventing a decrease in strength and forming a package 10 with high volumetric efficiency. Furthermore, the ratio (%) of the thickness of B to C is preferably 100±5% or less, and more preferably 100±2% or less.

In addition, because the connecting parts 24a to 24d are folded in half at the valley fold lines 11 and thermally bonded, it is possible to prevent a decrease in the barrier properties of the gaps between the adjacent side panels 22a to 22d. At this time, the valley fold lines 11 on the folded connecting parts 24a to 24d are inclined outwardly toward the top, and the upper ends of the valley fold lines 11 are arranged at the same height as the upper ends of the side panels 22a to 22d. As a result, the outer edge surface of the packaging material 100 is not exposed at the upper ends of the connecting parts 24a to 24d, and it is possible to prevent water vapor and the like from entering the main body part 20 through the thermal adhesive layer 103.

In addition, connecting portion 26b is thermally bonded to lid portion 30 together with flange plate 23b, and connecting portion 26a, which is disposed between connecting portion 24a and flange plate 23a, is disposed overlapping the side of flange plate 23a and thermally bonded to lid portion 30. This makes it possible to prevent gaps from being formed between the upper end of the ridge between adjacent side plates 22a and 22b and lid portion 30. Similarly, connecting portions 26c to 26h make it possible to prevent gaps from being formed at the upper ends between adjacent side plates 22a to 22d. This makes it possible to more reliably prevent a decrease in barrier properties.

In addition, the adhesive surfaces of the connecting portions 24a-24d, which are folded in half at the valley fold line 11 and heat-sealed, and the adhesive surfaces of the flange plates 23a, 23c, which are folded back at an angle on the valley fold line 11 and heat-sealed, do not overlap each other. This allows the connecting portions 24a-24d and the flange plates 23a, 23c to be easily heat-sealed in separate processes, and prevents wrinkles from occurring on the adhesive surfaces.

In this embodiment, the main body 20 of the package 10 has a bottom panel 21, side panels 22a-22d, and flange panels 23a-23d, and the outer periphery of the lid 30 is bonded onto the flange panels 23a-23d. In addition, the connecting portions 24a-24d (first connecting portions) that connect adjacent side panels 22a-22d are folded in half along the inclined valley fold line 11 (first fold line) and bonded.

This prevents a decrease in the barrier properties of the gaps between adjacent side panels 22a to 22d, and allows the packaging body 10 to be formed by folding the packaging material 100 made of a laminate. This improves the yield and volumetric efficiency of the packaging body 10.

In addition, by bending downward the flange plates 23a, 23b, 23d from which the metal tabs 41a, 41b do not protrude, the storage volume of the battery 1 can be reduced. This makes it possible to reduce the storage volume of each battery 1 when multiple batteries 1 are arranged side by side to increase the size, thereby improving the volumetric energy density of the entire battery.

Furthermore, connecting parts (second connecting parts) 26a to 26h are provided on both ends of the flange plates 23a to 23d, and the connecting parts (second connecting parts) 26a to 26h are connected to the upper ends of the connecting parts (first connecting parts) 24a to 24d via mountain fold lines (second fold lines) 12. Furthermore, the connecting parts (second connecting parts) 26a, 26d, 26e, and 26h are overlapped with the adjacent flange plates 23a and 23c, and the lid part 30 is adhered on top of them. This prevents gaps from being formed between the upper ends of the ridges between the adjacent side panels 22a to 22d and the lid part 30, preventing a decrease in barrier properties.

The ends of the flange plates 23a and 23c are folded back at an angle by a valley fold on the thermal adhesive layer 103 side and adhered, and the connecting parts (second connecting parts) 26a, 26d, 26e, and 26h are overlapped on the adjacent flange plates 23a and 23c. This makes it easy to form a ring-shaped continuous flange F.

In addition, the upper ends of the valley fold lines (first fold lines) 11 on the connecting parts 24a to 24d are positioned at the same height as the upper ends of the side panels 22a to 22d. This prevents the outer edge of the packaging material 100 from being exposed at the upper end of the connecting part (first connecting part) that is folded in half, and prevents water vapor and the like from entering the main body part 20 through the thermal adhesive layer 103.

In addition, by making the ratio of the thickness of the barrier layer 102 at the intermediate position in the height direction of the side panels 22a to 22d to the thickness of the barrier layer 102 at the joint between the side panels 22a to 22d and the bottom panel 21 100±10% or less, it is possible to form a package 10 with high volumetric efficiency while preventing a decrease in strength by making the thickness of the barrier layer 102 approximately uniform in the height direction.

FIG. 5 is a development view showing a modified example of the main body 20 of the package 10 of this embodiment. The width W1 of the side panels 22a to 22d may be made smaller than the width W2 of the flange panels 23a to 23d. In this case, the valley fold lines 11 formed on both sides of the flange panels 23a, 23c are inclined at 45° with respect to the mountain fold lines 12 connecting the flange panels 23a, 23c to the side panels 22a, 22c.

Figure 6 is a development view showing a modified example of the main body 20 of the package 10 of this embodiment. A pair of mountain fold lines 12 are formed on both sides of the flange plates 23a, 23c, extending from the corners of the side plates 22a, 22c in a direction toward each other and diagonally crossing the flange plates 23a, 23c. The flange plates 23a, 23c are connected to the connecting portions 26a, 26d, 26e, 26h via valley fold lines 11.

The valley fold lines 11 connecting the flange plates 23a, 23c to the connecting portions 26a, 26d, 26e, 26h are bent, and the mountain fold lines 12 that cross the flange plates 23a, 23c diagonally are bent to fold both sides of the flange plates 23a, 23c and thermally bond them to the connecting portions 26a, 26d, 26e, 26h, respectively, using the thermal adhesive layers 103. At this time, the connecting portions 26a, 26d, 26e, 26h overlap both sides of the flange plates 23a, 23c, respectively. Therefore, the same effect as in this embodiment can be obtained in this modified example.

Second Embodiment
Figure 7 is a development view showing the main body 20 of the packaging body 10 of the battery 1 of the second embodiment. For ease of explanation, the same reference numerals are used for the same parts as those of the first embodiment shown in Figures 1 to 4 described above. This embodiment differs from the first embodiment in the shape of the connecting parts 24a to 24d. The other parts are the same as those of the first embodiment.

The width W1 of the side panels 22a to 22d is greater than the width W2 of the flange panels 23a to 23d. Because the width W2 of the flange panels 23a to 23d is small, the battery 1 can be made smaller and volumetric efficiency can be improved.

The distance W3 between the extension of the valley fold line 11 connecting the bottom panel 21 and the side panel 22a and the outer periphery of the connecting portion 26b and the distance W4 between the extension of the valley fold line 11 connecting the bottom panel 21 and the side panel 22a and the outer periphery of the connecting portion 26g are formed to be the same as the width W2 of the flange panel 23a. The connecting portions 24a, 24d (first connecting portions) are formed in an L-shape with a rectangular notch K1 shown by solid hatching at the corner. This allows the side ends of the connecting portions 26b, 26g to be positioned on the extension of the open end of the flange panel 23a when the side panel 22a is erected and the flange panel 23a is folded outward.

In the same way, the distance between the extension of the valley fold line 11 connecting the bottom panel 21 and the side panels 22b to 22d and the outer periphery of the connecting parts 26a to 26h is made the same as the width of the flange panel 23c. Also, the connecting parts 24b to 24d (first connecting parts) are formed in an L-shape with a rectangular notch K1, shown by solid hatching, at the corner. This allows the side ends of the connecting parts 26a to 26h to be positioned on the extension of the open ends of the flange panels 23b to 23d when the side panels 22b to 22d are erected and the flange panels 23b to 23d are folded outward. This allows the main body 20 to be formed compactly.

Because the connecting portions 24a to 24d are L-shaped, the valley fold lines 11 on the connecting portions 24a to 24d do not reach the extension of the mountain fold lines 12 between the side panels 22a to 22d and the flange panels 23a to 23d. Therefore, when the side panels 22a to 22d are erected, the upper ends of the valley fold lines 11 on the connecting portions 24a to 24d are lower than the side panels 22a to 22d.

Third Embodiment
Figure 8 is a development view showing the main body 20 of the packaging body 10 of the battery 1 of the third embodiment. For ease of explanation, the same parts as those of the first embodiment shown in Figures 1 to 4 above are given the same reference numerals. This embodiment differs from the first embodiment in the arrangement of the valley fold lines 11 and mountain fold lines 12 with respect to the connecting portions 26a to 26h and the flange plates 23a to 23d. The other parts are the same as those of the first embodiment.

A pair of valley fold lines 11 are formed on both sides of the flange plates 23b and 23d, extending from the corners of the side plates 22b and 22d in a direction approaching each other and crossing the flange plate 23b diagonally. The valley fold lines 11 are inclined at 45° with respect to the mountain fold lines 12 connecting the flange plate 23b and the side plate 22b and the mountain fold lines 12 connecting the flange plate 23d and the side plate 22d.

The connecting portion 24a is connected to the side panel 22b via the mountain fold line 12, and is connected to the side panel 22a without a fold line. Similarly, the connecting portion 24b is connected to the side panel 22b via the mountain fold line 12, and is connected to the side panel 22c without a fold line. The connecting portion 24c is connected to the side panel 22c via the mountain fold line 12, and is connected to the side panel 22d without a fold line. The connecting portion 24d is connected to the side panel 22a via the mountain fold line 12, and is connected to the side panel 22d without a fold line.

In addition, the connecting portion 26b is connected to the flange plate 23b and the connecting portion 24a via a mountain fold line (second fold line) 12. The connecting portion 26c is connected to the flange plate 23b and the connecting portion 24b via a mountain fold line (second fold line) 12. The connecting portion 26f is connected to the flange plate 23d and the connecting portion 24c via a mountain fold line (second fold line) 12. The connecting portion 26g is connected to the flange plate 23d and the connecting portion 24d via a mountain fold line (second fold line) 12.

In addition, connecting portion 26a is connected to flange plate 23a without a fold line, and is connected to connecting portion 24a via a mountain fold line (second fold line) 12. Similarly, connecting portion 26d is connected to flange plate 23c without a fold line, and is connected to connecting portion 24b via a mountain fold line (second fold line) 12. Connecting portion 26e is connected to flange plate 23c without a fold line, and is connected to connecting portion 24c via a mountain fold line (second fold line) 12. Connecting portion 26h is connected to flange plate 23a without a fold line, and is connected to connecting portion 24d via a mountain fold line (second fold line) 12.

The connecting portions 26b, 26c, 26f, and 26g are mountain-folded from both side ends of the flange plates 23b and 23d, respectively, and both side portions of the flange plates 23b and 23d are folded back at an angle on the valley fold line 11 and thermally bonded by the thermal adhesive layer 103 on the inner surface.

As a result, the connecting portions 26b and 26c overlap both sides of the flange plate 23b, and the connecting portions 26f and 26g overlap both sides of the flange plate 23d. As a result, an annular flange F is formed around the opening 20a, to which the flange plates 23a to 23d and the connecting portions 26a to 26h are connected. Therefore, the same effect as in the first embodiment can be obtained with this embodiment.

In addition, the adhesive surfaces of the connecting parts 24a-24d, which are folded in half at the valley fold line 11 and heat-sealed, and the flange plates 23b, 23d, which are folded back at an angle on the valley fold line 11 and heat-sealed, do not overlap each other. This makes it easy to heat-seal the connecting parts 24a-24d and the flange plates 23b, 23d in separate processes, and prevents wrinkles from forming on the adhesive surfaces.

In this embodiment, the connecting portions 24a to 24d may be formed in an L-shape, as in the second embodiment.

Figure 9 is a development view showing a modified example of the main body 20 of the package 10 of this embodiment. A pair of mountain fold lines 12 are formed on both sides of the flange plates 23b, 23d, extending from the corners of the side plates 22b, 22d in a direction toward each other and diagonally crossing the flange plates 23b, 23d. In addition, the flange plates 23b, 23d are connected to the connecting parts 26b, 26c, 26f, 26g via valley fold lines 11.

The valley fold lines 11 connecting the flange plates 23b, 23d to the connecting portions 26b, 26c, 26f, 26g are bent, and the mountain fold lines 12 that cross the flange plates 23b, 23d diagonally are bent, folding both sides of the flange plates 23b, 23d and thermally bonding them to the connecting portions 26b, 26c, 26f, 26g, respectively, with the thermal adhesive layers 103. At this time, the connecting portions 26b, 26c, 26f, 26g overlap both sides of the flange plates 23b, 23d, respectively. Therefore, the same effect as in this embodiment can be obtained with this modified example.

Fourth Embodiment
Figure 10 is a development view showing the main body 20 of the packaging body 10 of the battery 1 of the fourth embodiment. For ease of explanation, the same parts as those of the first embodiment shown in Figures 1 to 4 are given the same reference numerals. This embodiment differs from the first embodiment in the arrangement of the valley fold lines 11 and mountain fold lines 12 with respect to the connecting portions 26a, 26d, 26e, and 26h and the flange plates 23a and 23c. The other parts are the same as those of the first embodiment.

The connecting portions 26a, 26d, 26e, and 26h have mountain fold lines 12 that run from the corners of the side panels 22a and 22c across the connecting portions 26a, 26d, 26e, and 26h. The mountain fold lines 12 are inclined at 45° with respect to the fold lines (second fold lines) that connect the connecting portions 26a, 26d, 26e, and 26h to the connecting portions 24a to 24d.

In addition, connecting portion 26a is connected to flange plate 23a without a fold line, and is connected to connecting portion 24a via a valley fold line (second fold line) 11. Similarly, connecting portion 26d is connected to flange plate 23c without a fold line, and is connected to connecting portion 24b via a valley fold line (second fold line) 11. Connecting portion 26e is connected to flange plate 23c without a fold line, and is connected to connecting portion 24c via a valley fold line (second fold line) 11. Connecting portion 26h is connected to flange plate 23a without a fold line, and is connected to connecting portion 24d via a valley fold line (second fold line) 11.

In addition, connecting portion 26b is connected to flange plate 23b without a fold line, and is connected to connecting portion 24a via a mountain fold line (second fold line) 12. Similarly, connecting portion 26c is connected to flange plate 23b without a fold line, and is connected to connecting portion 24b via a mountain fold line (second fold line) 12. Connecting portion 26f is connected to flange plate 23d without a fold line, and is connected to connecting portion 24c via a mountain fold line (second fold line) 12. Connecting portion 26g is connected to flange plate 23d without a fold line, and is connected to connecting portion 24d via a mountain fold line (second fold line) 12.

The flange plates 23a to 23d are mountain folded from the upper ends of the side plates 22a to 22d, and the connecting portions 26a, 26d, 26e, and 26h are valley folded from the upper ends of the connecting portions 24a to 24d. Also, the connecting portions 26b, 26c, 26f, and 26g are mountain folded from the upper ends of the connecting portions 24a to 24d. At this time, the connecting portions 26a, 26d, 26e, and 26h are folded in half on the mountain fold line 12 and thermally bonded onto the adjacent connecting portions 26b, 26c, 26f, and 26g with the thermal adhesive layer 103, and the lid portion 30 is bonded on top of them.

As a result, one of the adjacent connecting parts 26a, 26b sandwiching the connecting part 24a is folded by a mountain fold and adhered to the other. Similarly, one of the adjacent connecting parts 26c, 26d sandwiching the connecting part 24b is folded by a mountain fold and adhered to the other. Also, one of the adjacent connecting parts 26e, 26f sandwiching the connecting part 24c is folded by a mountain fold and adhered to the other. Also, one of the adjacent connecting parts 26g, 26h sandwiching the connecting part 24d is folded by a mountain fold and adhered to the other. As a result, an annular flange F in which the flange plates 23a to 23d and the connecting parts 26a to 26h are connected is formed around the opening 20a. Therefore, the same effect as in the first embodiment can be obtained in this embodiment.

In addition, the adhesive surfaces of connecting parts 24a to 24d, which are folded in half at valley fold line 11 and heat-sealed, do not overlap with the adhesive surfaces of connecting parts 26a, 26d, 26e, and 26h, which are heat-sealed onto adjacent connecting parts 26b, 26c, 26f, and 26g. This allows connecting parts 24a to 24d and connecting parts 26a, 26d, 26e, and 26h to be easily heat-sealed in separate processes, and prevents wrinkles from occurring on the adhesive surfaces.

In this embodiment, the connecting portions 24a to 24d may be formed in an L-shape, as in the second embodiment.

Fifth Embodiment
Fig. 11 is a development view showing the main body 20 of the packaging body 10 of the battery 1 of the fifth embodiment. For ease of explanation, the same parts as those of the fourth embodiment shown in Fig. 10 above are given the same reference numerals. This embodiment differs from the fourth embodiment in the arrangement of the valley fold lines 11 and mountain fold lines 12 for the connecting portions 26a to 26h. The other parts are the same as those of the fourth embodiment.

The connecting portions 26b, 26c, 26f, and 26g have mountain fold lines 12 that run from the corners of the side panels 22b and 22d across the connecting portions 26b, 26c, 26f, and 26g. The mountain fold lines 12 are inclined at 45° with respect to the fold lines (second fold lines) that connect the connecting portions 26b, 26c, 26f, and 26g to the connecting portions 24a to 24d.

In addition, connecting portion 26a is connected to flange plate 23a without a fold line, and is connected to connecting portion 24a via a mountain fold line (second fold line) 12. Similarly, connecting portion 26d is connected to flange plate 23c without a fold line, and is connected to connecting portion 24b via a mountain fold line (second fold line) 12. Connecting portion 26e is connected to flange plate 23c without a fold line, and is connected to connecting portion 24c via a mountain fold line (second fold line) 12. Connecting portion 26h is connected to flange plate 23a without a fold line, and is connected to connecting portion 24d via a mountain fold line (second fold line) 12.

In addition, connecting portion 26b is connected to flange plate 23b without a fold line, and is connected to connecting portion 24a via a valley fold line (second fold line) 11. Similarly, connecting portion 26c is connected to flange plate 23b without a fold line, and is connected to connecting portion 24b via a valley fold line (second fold line) 11. Connecting portion 26f is connected to flange plate 23d without a fold line, and is connected to connecting portion 24c via a valley fold line (second fold line) 11. Connecting portion 26g is connected to flange plate 23d without a fold line, and is connected to connecting portion 24d via a valley fold line (second fold line) 11.

The flange plates 23a to 23d are mountain folded from the upper ends of the side plates 22a to 22d, and the connecting portions 26b, 26c, 26f, and 26g are valley folded from the upper ends of the connecting portions 24a to 24d. Also, the connecting portions 26a, 26d, 26e, and 26h are mountain folded from the upper ends of the connecting portions 24a to 24d. At this time, the connecting portions 26b, 26c, 26f, and 26g are folded in half on the mountain fold line 12 and are thermally bonded onto the adjacent connecting portions 26a, 26d, 26e, and 26h with the thermal adhesive layer 103, and the lid portion 30 is bonded on top of them.

As a result, one of the adjacent connecting parts 26a, 26b sandwiching the connecting part 24a is folded by a mountain fold and adhered to the other. Similarly, one of the adjacent connecting parts 26c, 26d sandwiching the connecting part 24b is folded by a mountain fold and adhered to the other. Also, one of the adjacent connecting parts 26e, 26f sandwiching the connecting part 24c is folded by a mountain fold and adhered to the other. Also, one of the adjacent connecting parts 26g, 26h sandwiching the connecting part 24d is folded by a mountain fold and adhered to the other. As a result, an annular flange F in which the flange plates 23a to 23d and the connecting parts 26a to 26h are connected is formed around the opening 20a. Therefore, the same effect as in the first embodiment can be obtained in this embodiment.

In addition, the adhesive surfaces of connecting parts 24a to 24d, which are folded in half at valley fold line 11 and heat-sealed, do not overlap with the adhesive surfaces of connecting parts 26b, 26c, 26f, and 26g, which are heat-sealed onto adjacent connecting parts 26a, 26d, 26e, and 26h. This allows connecting parts 24a to 24d and connecting parts 26b, 26c, 26f, and 26g to be easily heat-sealed in separate processes, preventing wrinkles from forming on the adhesive surfaces.

In this embodiment, the connecting portions 24a to 24d may be formed in an L-shape, as in the second embodiment.

Sixth Embodiment
Figure 12 is a development view showing the main body 20 of the packaging body 10 of the battery 1 of the sixth embodiment. For ease of explanation, the same parts as those of the first embodiment shown in Figures 1 to 4 are given the same reference numerals. This embodiment differs in the arrangement of the valley fold lines 11 with respect to the connecting parts 26a, 26d, 26e, and 26h and the flange plates 23a and 23c. The other parts are the same as those of the first embodiment.

At the connecting portions 26a, 26d, 26e, and 26h, valley fold lines 11 are formed that run from the corners of the side panels 22a and 22c across the connecting portions 26a, 26d, 26e, and 26h. These valley fold lines 11 are inclined at 45° with respect to the mountain fold lines (second fold lines) 12 that connect the connecting portions 26a, 26d, 26e, and 26h to the connecting portions 24a to 24d.

The flange plates 23a to 23d are mountain-folded from the upper ends of the side plates 22a to 22d, and the connecting portions 26a to 26h are mountain-folded from the upper ends of the connecting portions 24a to 24d. At this time, the connecting portions 26a, 26d, 26e, and 26h are folded in half along the valley fold line 11 and are thermally bonded by the thermal adhesive layer 103 on the inner surface.

As a result, one of the adjacent connecting parts 26a, 26b across connecting part 24a is folded, and one of the adjacent connecting parts 26c, 26d across connecting part 24b is folded. Also, one of the adjacent connecting parts 26e, 26f across connecting part 24c is folded, and one of the adjacent connecting parts 26g, 26h across connecting part 24d is folded. As a result, an annular flange F is formed around opening 20a, connecting flange plates 23a-23d and connecting parts 26b, 26c, 26f, 26g. Therefore, the same effect as in the first embodiment can be obtained with this embodiment.

In this embodiment, the connecting portions 24a to 24d may be formed in an L-shape, as in the second embodiment.

Seventh Embodiment
Fig. 13 is a development view showing the main body 20 of the packaging body 10 of the battery 1 of the sixth embodiment. For ease of explanation, the same parts as those of the sixth embodiment shown in Fig. 12 above are given the same reference numerals. This embodiment differs from the sixth embodiment in the arrangement of the valley fold lines 11 and mountain fold lines 12 for the connecting portions 26a to 26h. The other parts are the same as those of the sixth embodiment.

A valley fold line 11 is formed in the connecting portions 26b, 26c, 26f, and 26g, which crosses the connecting portions 26b, 26c, 26f, and 26g from the corners of the side panels 22b and 22d. This valley fold line 11 is inclined at 45° with respect to the mountain fold line (second fold line) 12 that connects the connecting portions 26b, 26c, 26f, and 26g to the connecting portions 24a to 24d.

The connecting portion 24a is connected to the side panel 22b via a mountain fold line 12, and is connected to the side panel 22a without a fold line. Similarly, the connecting portion 24b is connected to the side panel 22b via a mountain fold line 12, and is connected to the side panel 22c without a fold line. The connecting portion 24c is connected to the side panel 22d via a mountain fold line 12, and is connected to the side panel 22c without a fold line. The connecting portion 24d is connected to the side panel 22d via a mountain fold line 12, and is connected to the side panel 22a without a fold line.

In addition, the connecting portion 26b is connected to the flange plate 23b and the connecting portion 24a via a mountain fold line (second fold line) 12. The connecting portion 26c is connected to the flange plate 23b and the connecting portion 24b via a mountain fold line (second fold line) 12. The connecting portion 26f is connected to the flange plate 23d and the connecting portion 24c via a mountain fold line (second fold line) 12. The connecting portion 26g is connected to the flange plate 23d and the connecting portion 24d via a mountain fold line (second fold line) 12.

In addition, connecting portion 26a is connected to flange plate 23a without a fold line, and is connected to connecting portion 24a via a mountain fold line (second fold line) 12. Similarly, connecting portion 26d is connected to flange plate 23c without a fold line, and is connected to connecting portion 24b via a mountain fold line (second fold line) 12. Connecting portion 26e is connected to flange plate 23c without a fold line, and is connected to connecting portion 24c via a mountain fold line (second fold line) 12. Connecting portion 26h is connected to flange plate 23a without a fold line, and is connected to connecting portion 24d via a mountain fold line (second fold line) 12.

The flange plates 23a to 23d are mountain-folded from the upper ends of the side plates 22a to 22d, and the connecting portions 26a to 26h are mountain-folded from the upper ends of the connecting portions 24a to 24d. At this time, the connecting portions 26b, 26c, 26f, and 26g are folded in half along the valley fold line 11 and are thermally bonded by the thermal adhesive layer 103 on the inner surface.

As a result, an annular flange F is formed around the opening 20a, with the flange plates 23a to 23d and the connecting portions 26a, 26d, 26e, and 26h connected. Therefore, the same effect as in the first embodiment can be obtained with this embodiment.

In this embodiment, the connecting portions 24a to 24d may be formed in an L-shape, as in the second embodiment.

The connecting portions 26a-26h and some of the flange plates 23a-23d of the first to seventh embodiments may be replaced with the connecting portions 26a-26h and flange plates 23a-23d of other embodiments, and the arrangements of the valley fold lines 11 and mountain fold lines 12 on the connecting portions 26a-26h and flange plates 23a-23d may be combined.

The present invention is not limited to the above-described embodiment, and various other modifications are possible. For example, in the above embodiment, rectangular shape means approximately rectangular or rectangular. Similarly, the connecting portions (first connecting portions) 24a to 24d may be approximately square. In addition, the valley fold line 11, which is inclined at 45 degrees, may be slightly deviated within the margin of error.

The widths W1, W2, and distances W3 and W4 may also deviate slightly within the margin of error. For example, in the first embodiment, the width W1 of the side panels 22a to 22d (the depth when the package 10 is assembled) may deviate slightly from the width W2 of the flange panels 23a to 23c within the margin of error. Furthermore, the distance W3 between the extension line of the valley fold line 11 connecting the bottom panel 21 and the side panels 22a, 22c and the outer periphery of the lid portion 30 may deviate slightly from the width W2 of the flange panels 23a to 23c within the margin of error.

In addition to being in a sheet shape, the lid portion 30 may also be formed by folding the packaging material 100 into a tray shape, similar to the main body portion 20.

The effects of the present invention will be explained in more detail below using examples.

Examples 1 to 7 are packaging bodies 10 of the first embodiment, and the packaging body 10 was formed by folding one sheet of packaging material 100 along valley fold lines 11 and mountain fold lines 12 formed by pressing. The opening 20a of the main body 20 was 100 mm x 240 mm, and the radius of curvature of the connecting portion between the bottom plate 21 and the side plates 22a to 22d was 0.5 mm. The radius of curvature of the connecting portion between the side plates 22a to 22d and the flange plates 23a to 23d was 0.5 mm. In Examples 1 to 7, the depth H of the packaging body 10 (corresponding to the width W1 in Figure 3) was 3 mm, 4 mm, 5 mm, 6 mm, 10 mm, 15 mm, and 20 mm, respectively.

The base layer 101 of the packaging material 100 was made by bonding a polyethylene terephthalate film (thickness 12 μm) and a stretched nylon film (thickness 15 μm) with a dry laminate adhesive (thickness 3 μm). The barrier layer 102 was made of aluminum alloy foil (thickness 40 μm). The adhesive layer 104 was made by bonding the aluminum alloy foil and the stretched nylon film with a dry laminate adhesive (thickness 3 μm). The thermal adhesive layer 103 was made of a polypropylene film (thickness 40 μm). The adhesive layer 105 was made of acid-modified polypropylene (thickness 40 μm).

In addition, in Comparative Examples 1 to 4, the same laminate as packaging material 100 in Examples 1 to 7 was cold-press molded to form trays with the same volume as Examples 1 to 7. Specifically, in Comparative Examples 1 to 4, packaging material 100 was cut into a rectangle (150 mm x 300 mm) and a tray was formed by cold-press molding using male and female molding dies. The short sides of the cut packaging material 100 coincide with the MD (machine direction) of the packaging material 100, and the long sides coincide with the TD (width direction) of the packaging material 100.

The female molding die has a rectangular opening (100 mm x 240 mm) and is made of a die with a maximum height roughness (nominal Rz value) of 3.2 μm as specified in "Appendix 1 (Reference) Table 2 of Comparative Surface Roughness Standard Pieces" of JIS B 0659-1:2002. The corners of the female molding die are 0.5 mm, and the ridges are 0.5 mm. These values correspond to the radius of curvature of the connecting part between the side plate and the flange plate after press molding.

The male molding die is made of a die with a maximum height roughness (nominal Rz value) of 1.6 μm, as specified in "Appendix 1 (Reference) Table 2 of Comparative Surface Roughness Standard Pieces" of JIS B 0659-1:2002. The corners of the male molding die are 0.5 mm, and the ridges are 0.5 mm. These values correspond to the radius of curvature of the connecting part between the bottom plate and the side plate after press molding. The clearance between the male molding die and the female molding die was set to 0.3 mm.

The packaging material 100 is placed so as to cover the opening of the female molding die, and cold press molded with the male molding die. At this time, the MD of the packaging material 100 is aligned with the short side of the opening of the molding die, and the TD of the packaging material 100 is aligned with the long side of the opening of the molding die, and the packaging material 100 is placed on the female molding die and press molded so that the thermal adhesive resin layer abuts against the male molding die side.

In addition, Comparative Examples 1 to 4 were molded to a molding depth (tray depth H) of 3 mm, 4 mm, 5 mm, and 6 mm, respectively.

Figure 14 is a top view of the package 10, and Figure 15 is a cross-sectional view of line X-X in Figure 14. Figure 15 shows the layer structure of the package 100. As shown in Figure 14, the packages molded in Examples 1 to 7 and Comparative Examples 1 to 4 were cut in the thickness direction along a straight line L passing through corner P1 of the connecting portion 26b and corner P2 of the opening 20a when viewed from above in a plan view of the opening 20a, using a microtome (manufactured by Daiwa Koki Kogyo Co., Ltd., product number: REM-710 ritratome) to divide the package into two. The cross section obtained was observed with a laser microscope (manufactured by Keyence Corporation, product number: VK-9700) to measure the thickness of the barrier layer 102, and the results are shown in Table 1.

The thickness of the barrier layer 102 was measured at the junction between the side panel and the flange panel (indicated by A in Table 1), at the midpoint of the height of the side panel (indicated by B in Table 1), and at the junction between the side panel and the bottom panel (indicated by C in Table 1). In addition, for the packages 10 of Examples 1 to 7, the thickness of the barrier layer 102 was measured at the junction between the connecting portion 24a and the connecting portion 26b (indicated by A in Table 1), at the midpoint of the height of the connecting portion 24a (indicated by B in Table 1), and at the junction between the connecting portion 24a and the bottom panel 21 (indicated by C in Table 1).

From the measured thicknesses A to C at each position, the ratio (%) of the thickness of A to C was calculated by (A/C) x 100 and summarized in Table 1. The ratio (%) of the thickness of B to C was calculated by (B/C) x 100 and summarized in Table 1. The barrier layer 102 after molding was visually checked for cracks by shining light on it in a dark room. The presence or absence of cracks was checked for 10 samples, and when no cracks were found in any of the samples, it is indicated by "O", and when cracks were found in any of the samples, it is indicated by "X".

As is clear from Table 1, by forming the package 10 along the valley fold lines 11 and mountain fold lines 12 formed by creasing, the depth of the main body 20 can be increased, thereby increasing the capacity of the package 10. In addition, the ratio of the thickness of A to C and the ratio of the thickness of B to C (%) are 100±2% or less, and the thickness of the barrier layer 102 is approximately the same in the height direction, making it possible to form a package 10 with high volumetric efficiency while preventing a decrease in strength.

The present invention can be used for battery packaging that packages battery elements.

1 Battery 10 Battery packaging (packaging)
11 Valley fold line 12 Mountain fold line 20 Main body portion 20a Opening 21 Bottom plate 22a to 22d Side plate 23a to 23d Flange plate 24a to 24d Connecting portion (first connecting portion)
26a to 26h connecting portion (second connecting portion)
30 Lid 40 Battery element 41a, 41b Metal tab 100 Packaging material 101 Base material layer 102 Barrier layer 103 Thermal adhesive layer (thermally adhesive resin layer)
104 Adhesive layer 105 Adhesive layer K1 Notch F Flange P Corner L Straight line

Claims (6)

A battery packaging body is constructed of a laminate including at least a barrier layer and a heat-sealable resin layer disposed as an innermost layer, the battery packaging body including a main body having an opening on an upper surface thereof for accommodating a battery element, and a lid for closing the opening,
The main body portion has a rectangular bottom plate, side plates bent from four sides of the bottom plate and erected, first connecting portions connecting adjacent side plates, flange plates bent outward from upper ends of the four side plates, and second connecting portions disposed on both ends of the flange plates,
The lid portion has an outer periphery bonded to the flange plate,
The first connecting portion is substantially square, and is folded in half by a valley fold on the thermally adhesive resin layer side at a first fold line that extends from a corner of the bottom plate at an inclination outwardly upward, and is bonded to the bottom plate;
The upper end of the first fold line is disposed at the same height as the upper end of the side panel,
The second connecting portion is connected to an upper end of the first connecting portion via a second fold line formed by folding the heat-sealable resin layer side in a mountain or valley manner,
A battery packaging body characterized in that the end of the flange plate is folded back and adhered at an angle by a valley fold on the heat-sealable resin layer side, and the second connecting portion adjacent to the end of the flange plate is overlapped on top of it. The battery packaging body according to claim 1, characterized in that the first fold line is inclined at 45° to the vertical direction. The battery packaging body according to claim 1 or 2, characterized in that the ratio of the thickness of the barrier layer at the intermediate position in the height direction of the side panel to the thickness of the barrier layer at the joint between the side panel and the bottom panel is 100±10% or less. A battery comprising a battery element having at least a positive electrode, a negative electrode, and an electrolyte housed within the main body of the battery packaging according to any one of claims 1 to 3. A battery comprising a battery element including at least a positive electrode and a negative electrode and integrated with a solid electrolyte, the battery element being housed within the main body of the battery packaging according to any one of claims 1 to 3. 6. The battery according to claim 4, wherein metal tabs of the positive and negative electrodes protrude from between the flange plate and the lid portion, and the flange plate from which the metal tabs do not protrude is bent downward.

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