JP6202753B2 - Battery container, film packaging battery, and battery container manufacturing method - Google Patents

Description

The present invention relates to a battery container, a film package battery, and a method for manufacturing the battery container .

Conventionally, as a battery container that houses battery elements such as lithium ion secondary batteries and electric double layer capacitors (all charging and power generation elements including electrolytes), a deep-drawn metal container having excellent water vapor barrier properties A metal sealed container having a welded structure in which a lid is welded and sealed is often used. However, a metal sealed container with a welded structure is heavy, bulky, has a problem that the welding process is complicated and lacks productivity. In particular, the welding process between the metal container main body and the lid requires a large number of man-hours and is problematic from the viewpoint of productivity. Moreover, since lithium batteries for electric vehicles have a large number of battery containers mounted on the vehicle, it is desired to make the battery containers as light and compact as possible.
In response to these demands, a pouch-shaped container in which a laminated body in which a base material layer, a metal foil such as aluminum, and a sealant layer are laminated in order is formed into a bag shape, or a concave portion is formed by press molding the laminated body. However, film-wrapped batteries such as embossed containers (also referred to as “drawn-molded containers”) that store lithium ion battery bodies in the recesses have been developed (see, for example, Patent Documents 1 and 2).
A battery container using a draw-molded container can accommodate even a battery element having a certain thickness and is easy to fill and wrap the battery element. Volume efficiency (volume efficiency is the volume of the battery element relative to the total volume of the battery container. The ratio is high, the weight is easily reduced, and the price is low.

JP 2002-216713 A JP 2010-262932 A

By the way, as described in Patent Documents 1 and 2, when a battery container using a draw-molded container is used with a lubricant such as fatty acid amide or liquid paraffin, the embossing mold and the surface of the laminate are formed. Since the slipping property is increased, the squeezing property can be improved. However, even if the drawability is improved, since the metal foil is drawn into a three-dimensional shape, there is a limit to the drawing depth, and the upper limit is about 10 mm as the depth of the draw-molded container. Therefore, the battery container using the draw-molded container has a problem that it cannot accommodate a battery element having a large capacity and a large thickness.
Further, since the corner of the draw-molded container is particularly greatly stretched, the metal foil becomes thin at the corner, causing a small crack or a pinhole. When moisture enters from a small crack portion or pinhole in the metal foil, the electrolytic solution reacts with moisture to generate hydrofluoric acid or the like. For this reason, there existed a problem that the welding part of an electrode member etc. corroded and deteriorated and electrolyte solution leaked.

The present invention has been made in view of the above circumstances, and, like a battery container using a draw-molded container, is lightweight, has high volumetric efficiency, and can easily accommodate a battery element having a large capacity and a large thickness. It is an object of the present invention to provide a battery container that has high productivity and can be manufactured at low cost, a film package battery using the battery container, and a manufacturing method thereof.
In addition, in this specification, although the concave wall of a battery container may be described as a side wall for convenience of explanation, the same part is pointed out.

The present invention provides the following battery containers.
(1) A battery container having a container main body formed from a laminated film having a metal foil and a welded layer, and a lid member, and the peripheral wall of the container main body has a welded layer of the laminated film on the storage unit side. are squeezed molded so as to be convex, and, welding layer of both end faces of the concave wall are a pair of opposing that rises folded from the bottom of the recess is formed the container body outer surface, it is folded from the bottom of the container body A battery container that is welded and connected to the welded layers on both side edges of a pair of opposing wall surfaces that rise.
(2) the concave wall, the welding layer of the folds folded portion to the bottom portion of the container body, the battery container according to the welding (1) to the welding layer of the bottom portion of the container body.
(3) The battery container according to (1) or (2), wherein a reinforcing resin is filled in the concave portion of the concave wall.

Moreover, this invention provides the following film packaging batteries.
(4) A film package battery using the battery container according to any one of (1) to (3), housing the battery element to the container body, a sealed film package battery the cover material .

Moreover, this invention provides the manufacturing method of the following battery containers.
(5) It has a container body formed from a laminated film having a metal foil and a welded layer, and the peripheral wall of the container body is drawn so that the welded layer of the laminated film is convex toward the storage part , Further, both sides of the pair of opposing wall surfaces, which are formed with concave portions on the outer surface and are folded from the bottom portion of the container body and rise on both side end surfaces of the opposing concave walls, are folded from the bottom portion of the container body. A method of manufacturing a battery container which is welded and connected to a welded layer at an edge, wherein the parts serving as the bottoms of a plurality of container bodies arranged at regular intervals in the longitudinal direction of the long laminated film Between the two sides of the laminated film in the width direction, the drawing film is formed by drawing at an interval longer than the length of the portion welded to the two opposite side surfaces of the adjacent recessed walls. Process and Width of the laminated film is the width of the bottom portion of the container body, and the concave wall provided a notch in the laminated film of the diaphragm molded portion not surrounding the concave wall so as to spread outwardly as a plurality of free end Concave shape that rises by bending from the root of the folded portion with respect to the bottom portion of the container body so that the welded layers face each other, the concave walls on both sides of the laminated film, and the film notch step A wall rising step and an end wall of the laminated film where the concave wall does not exist is bent and raised from the root of the end of the concave wall with respect to the bottom portion of the container body . And a step of connecting the wall surfaces forming the peripheral wall of the container main body by connecting the end walls and the concave walls by welding both side edges of the end walls on the welding layers on both side end surfaces of the concave walls. Process Method for producing a battery container, characterized in that.

Since the battery container and the film packaging battery of the present invention are composed of a laminated film containing a thin metal foil, the bottom of the container body and the peripheral wall of the battery container are similar to the battery container using the draw-molded container. The container has a high gas barrier property, is lightweight, and has a high volumetric efficiency.
In addition, unlike the battery container using the draw-molded container, the battery container and the film-wrapped battery of the present invention have a welded layer on both side end surfaces of a pair of opposing concave walls that rise when the peripheral wall is folded from the bottom. Since it is welded and connected to the welded layers on both side edges of the pair of opposing end walls that stand up, the watertight structure can be formed and the shape retention is excellent.
Moreover, the battery container and film packaging battery of this invention can accommodate the battery element of arbitrary thickness by bend | folding the laminated | multilayer film containing metal foil with a fold line. As a result, it is possible to accommodate a large-capacity thick battery element, so there is no need to emboss deeply into a three-dimensional shape, so even if the metal foil is thin, cracks and pinholes may occur in the metal foil. There is nothing.
In addition, the battery container and the film packaging battery of the present invention are laminated using a metal foil having low malleability and low drawability, which cannot be used for a draw-molded container when the thickness of the metal foil is reduced in the prior art. Film can also be used.
Furthermore, since the concave wall and the lid are welded, at least two opposing sides of the film-packed battery can be sealed by welding the lid to the concave wall. Thereby, since the welding part of a cover material does not extend outside a battery container, a battery becomes compact and the volume of an accumulation body can be made small when using a plurality of battery containers integrated. Moreover, it is excellent in the handleability at the time of storage and integration of a plurality of battery containers.
In addition, since the seal width can be sufficiently increased when the concave wall and the lid member are welded, the welding is easy and reliable, and the gas barrier property is also improved.

  According to the second aspect of the present invention, the welded layer of the folded portion that folds over the bottom of the concave wall is welded to the welded layer of the bottom, so that a watertight structure is formed and shape retention is more excellent. . In addition, it is easy and reliable to weld the welded layers on the both end faces of the concave wall and the welded layers on the both side edges of the wall surface that is folded from the bottom.

  According to the third aspect of the invention, since the concave resin is filled with the reinforcing resin, the shape retention is more excellent. Further, it is easy and reliable to weld the welded layers on both end surfaces of the concave wall and the welded layers on both side edges of the wall surface that is folded from the bottom.

  Moreover, according to the manufacturing method of the battery container and film packaging battery of this invention, a some battery container main body can be continuously formed using a elongate laminated film. Thereby, a battery container and a film packaging battery can be continuously manufactured, rewinding the laminated film wound up by roll, bobbin winding, and cassette winding, and the laminated film by which the part used as a concave wall was draw-molded. Therefore, productivity of a battery container and a film packaging battery can be improved.

It is a perspective view which shows the external shape of the battery container of a 1st form example. It is a side view of the battery container of a 1st form example. (A) is the side view of the II-II direction of FIG. 1, and (b) is the side view which expanded the part. It is sectional drawing of the battery container of a 1st form example. (A) is the arrow sectional drawing of the II direction of FIG. 1, (b) is sectional drawing to which the one part was expanded. It is an external view of the film packaging battery using the battery container of the 1st form example. (A) is a perspective view, (b) is the figure which expanded a part of side view. In manufacture of the battery container of a 1st example, it is a perspective view which shows formation of the recessed part of the concave wall by drawing. In manufacture of the battery container of a 1st form example, it is a perspective view which shows the resin molding formed in the recessed part of a concave wall. It is a perspective view which shows a film notch process in manufacture of the battery container of a 1st form example. It is a schematic cross section which shows an example of the metal mold | die of the injection molding machine used for a drawing molding process in manufacture of the battery container of a 1st form example. FIG. 5 is a schematic cross-sectional view showing a drawing process in manufacturing the battery container of the first embodiment. In manufacture of the battery container of a 1st form example, it is a schematic cross section which shows formation of the resin molding to the recessed part of a concave wall. In manufacture of the battery container of a 1st form example, it is a schematic cross section which shows mold release from the metal mold | die of the draw-processed laminated film. It is a perspective view which shows the standing-up process of a concave wall in manufacture of the battery container of a 1st form example. It is a perspective view which shows the connection process of a wall surface in manufacture of the battery container of a 1st form example. It is a perspective view which shows a draw molding process in manufacture of the battery container of the 1st form example using a elongate laminated film. It is a perspective view which shows a film notch process in manufacture of the battery container of the 1st form example using a elongate laminated film. In manufacture of the battery container of the 1st form example using a elongate laminated film, it is a perspective view which shows the standing-up process of a concave wall. It is a top view for demonstrating the state of a film notch in manufacture of the battery container of the 1st form example using a elongate laminated film. In manufacture of the battery container of the 1st form example using a elongate laminated film, it is a perspective view which shows a part of standing-up process of a concave wall. It is a perspective view which shows a part of connection process of a wall surface in manufacture of the battery container of a 1st form example using a elongate laminated film. It is a perspective view which shows the storage process of a battery element in manufacture of the battery container of a 1st form example using a elongate laminated film. It is a perspective view which shows a sealing process in manufacture of the battery container of the 1st form example using a elongate laminated film. It is a figure which shows the external shape of the battery container of a 2nd form example. (A) is a perspective view, (b) is the figure which expanded a part of side view. It is a figure which shows the external shape of the battery container of a 3rd form example. (A) is a perspective view, (b) is a side view. It is the figure which expanded a part of side view of the battery container of a 4th form example.

Embodiments of the present invention will be described below with reference to the drawings.
<First embodiment>
The battery container 10 of the first embodiment shown in FIGS. 1 to 3 has a container body 4 made of a laminated film 1 having a metal foil and a welded layer.
The battery container 10 of the first embodiment is a film package battery 20 of the first embodiment shown in FIG. 4 with the lid 3 attached after the battery element 5 is stored in the container body 4. The film packaging battery 20 of the first embodiment is suitably used as a battery container such as a secondary battery or an electric double layer capacitor.

The film packaging battery 20 of the first embodiment has a battery element 5 having a positive electrode plate, a negative electrode plate, a separator, and an electrolytic solution inside the battery container 10. The battery element 5 includes all elements necessary for charging and power generation including the electrolyte.
In the film-packed battery 20 of the first embodiment, electrode leads 47 made of a positive electrode lead and a negative electrode lead, which are electrically connected to positive and negative electrode plates, protrude from the battery container 10 in opposite directions. The electrode lead 47 is attached to and electrically connected to the positive and negative electrode plates.
As the separator, a sheet-like member that can be impregnated with an electrolytic solution, such as a porous film made of a thermoplastic resin such as polyolefin, a nonwoven fabric, or a woven fabric, is used.

The battery container 10 of the first embodiment shown in FIGS. 1 to 3 has a container body 4 made of a laminated film 1 having a metal foil and a welded layer.
The container body 4 has a bottom 41 formed in a rectangular shape in plan view, a pair of end walls 42 and 42 rising from the end edge of the bottom 41, and a concave wall 45 formed on the outer surface, which is convex toward the storage side. A pair of concave walls 43, 43 that are drawn and raised from the side edge of the bottom 41, the plate-shaped resin molded body 2 formed in the concave 45 of the concave wall 43, and the outer edges of the end walls 42, 42 from the upper edge Lead sandwiching portions 44, 44 extending in the direction.

The peripheral wall of the container main body 4 is formed by end walls 42 and 42 and concave walls 43 and 43 being folded at a fold line made of a straight line, rising from a rectangular bottom 41, and being connected at the side ends. So it can be water-tight structure.
Since the container body 4 is formed of the laminated film 1 in which the portion where the peripheral wall rises from the bottom 41 is folded along a straight fold line, the embossing for narrowing the metal foil into a three-dimensional shape on the portion rising from the bottom 41 is performed. There is no need to apply.
Therefore, there is no numerical limitation on the depth at which the container body 4 can be adopted. In addition, the corner of the container body 4 is particularly greatly stretched to make the metal foil thinner, and no small cracks or pinholes are generated in the metal foil.

The laminated film 1 forming the container body 4 is a laminated film in which a metal foil and a welding layer having a thermoplastic resin layer as an innermost layer are laminated.
In the first embodiment, the laminated film 1 has a welded layer only on one side of the metal foil. In the laminated film 1, the welding layer is the innermost layer of the container body 4.
In the laminated film 1 used in the first embodiment, a protective layer made of a resin is preferably laminated on the surface of the metal foil opposite to the side on which the welding layer is laminated.
The protective layer prevents the outer surface of the metal foil from being corroded by moisture or an electrolytic solution, or the outer surface of the metal foil from coming into contact with other articles and being damaged. The protective layer is preferably formed of a thermoplastic resin or a thermosetting resin having a higher melting point than the weld layer.

Specific examples of the laminated film 1 include, for example, a protective layer formed of a resin such as polyester such as polyethylene terephthalate or polybutylene naphthalate or polyamide such as 6 nylon or 66 nylon, and a metal foil such as stainless steel or aluminum. In addition, a laminate in which a welding layer formed of polyolefin such as polyethylene or polypropylene is laminated in order can be given.
As the protective layer, it is preferable to use a biaxially stretched film because heat resistance and strength are increased, and a plurality of layers may be laminated.
As a method of laminating each layer constituting the laminated film 1, a known method such as dry lamination, extrusion lamination, thermocompression lamination, or the like can be adopted.

The metal foil of the laminated film 1 functions as a gas barrier layer that gives the laminated film 1 gas barrier properties such as oxygen and water vapor. Examples of the metal foil include aluminum foil (aluminum foil), aluminum alloy foil (aluminum alloy foil), stainless steel foil, iron foil, nickel foil, copper foil and lead foil.
Among these metal foils, an aluminum foil or an aluminum alloy foil is preferable because of its small specific gravity and excellent extensibility (easiness of extension) and thermal conductivity. When a metal foil excellent in thermal conductivity is used, the heat dissipation when the battery element generates heat is improved. When aluminum foil is used, the thickness of the aluminum foil is preferably in the range of 6 μm to 200 μm in view of ensuring gas barrier properties, processability, and the like. If the thickness of the aluminum foil is less than 6 μm, there is a concern that pinholes increase and the gas barrier property is lowered.

Stainless steel foil is inferior in thermal conductivity to aluminum foil, but is excellent in terms of high tensile strength and corrosion resistance. The metal foil having high corrosion resistance maintains the gas barrier property because the weld layer inside the metal foil in the container body 4 is damaged and the electrolyte filled in the battery container 10 is hardly corroded even if it contacts the metal foil. It is preferable in that it can be performed. When using a stainless steel foil, austenitic stainless steel such as SUS304 or SUS316, which is excellent in corrosion resistance, is preferable. As the stainless steel foil, SUS316 is particularly preferable. The thickness of the stainless steel foil is preferably in the range of 10 μm to 150 μm.
If the thickness of the stainless steel foil is less than 10 μm, the occurrence of pinholes is increased, and there is a concern that the gas barrier property is lowered. Moreover, when the thickness of the stainless steel foil exceeds 150 μm, it is difficult to process due to high rigidity.

  Examples of the resin used for the welded layer of the laminated film 1 include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear linear polyethylene, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, and ethylene- Polyethylene (PE) resins such as ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ionomer, ethylene-vinyl acetate copolymer, carboxylic acid-modified polyethylene; propylene homopolymer, propylene-ethylene random copolymer, Examples thereof include polyolefins such as ethylene-propylene block copolymers, propylene-α-olefin block copolymers, and polypropylene (PP) resins such as carboxylic acid-modified polypropylene.

As shown in FIG. 4, the film-packed battery 20 has a battery element 5 housed in a container body 4 of a battery container 10 and is sealed with a lid member 3. The lid member 3 is welded to the lid member welding surface of the concave wall 43, the lead holding portion 44, and the electrode lead 47. The lead holding portion 44 and the lid member 3 are welded with the electrode lead 47 interposed therebetween.
The lead sandwiching portion 44 of the container body 4 extends outward from the container body 4 by folding the laminated film 1 at the upper end of the end wall 42.
The lid member 3 is welded to the upper end surface of the concave wall 43 and the lead holding portion 44 to hold the electrode lead 47 and close the opening of the container body 4.
In the first embodiment, a member having the same laminated structure as the laminated film 1 of the container body 4 is used as the lid 3.

In the first embodiment, the lid member 3 has the same width as the container body 4. For this reason, the upper end of the concave wall 43 of the container body 4 is covered with the lid member 3. Therefore, if the concave wall 43 has a sufficient thickness, the container body 4 and the lid member 3 are welded with a sufficient welding width, so that the welding strength is high and the gas barrier property at the interface of the welding part can be increased. .
The lid member 3 may be formed wider than the width of the container body 4, and both side edge portions of the container body 4 may be covered with the lid member 3 that protrudes from the container body 4. In this case, a part of the lid member 3 is preferably fixed to the outer surface of the concave wall 43.

The structure of the laminated film used for the lid member 3 may not be the same as the laminated structure of the laminated film 1 of the container body 4. When the lid material 3 is a laminated film having a metal foil and a welded layer, the film packaging battery 20 can be reduced in weight and the volume ratio is increased, which is preferable. However, when a thick resin plate having a gas barrier property equivalent to that of the metal foil is used for the lid member 3, the metal foil need not be used.
When the lid 3 is a laminated film having a metal foil and a welded layer, it is preferable to laminate a protective layer similar to the laminated film 1 on the lid 3.

As shown in FIGS. 1 to 3, the side walls 43, 43 on both sides of the container body 4 are formed by drawing so that a concave portion 45 is formed on the outer surface and the storage portion side is convex. As for the laminated film 1 which comprises the side wall 43, the welding layer is orient | assigned to the accommodating part side.
As shown in FIGS. 2 and 3, the side wall 43 includes a folded portion 43 a in which the laminated film 1 is folded at the side edge of the bottom portion 41 toward the storage portion, and a rising portion 43 b that rises from the inner edge of the folded portion 43 a. The upper extending portion 43c extending outward from the upper edge of the rising portion 43b and the end extending portion 43d extending outward from both ends in the length direction of the rising portion 43b (FIG. 2 ( b)).
The folded portion 43 a is overlapped with the bottom portion 41. The welded layer of the folded portion 43a is preferably welded to the welded layer of the bottom portion 41 so that the folded portion 43a is fixed to the bottom portion 41.

The concave portion 45 on the outer surface of the side wall 43 is formed by a folded portion 43a, a rising portion 43b, an upper extending portion 43c, and an end extending portion 43d.
It is preferable that the depth of the recessed part 45 is a depth which can ensure the width | variety of the welding part with the cover material 3 and the end wall 42 to about 2-5 mm. When the width of the welded portion is 2 mm or more, the welding strength with the lid member 3 and the end wall 42 and the gas barrier property at the welded portion interface are enhanced.
On the other hand, even if the width of the welded portion exceeds 5 mm, further improvement in welding strength and gas barrier property cannot be expected, and the volumetric efficiency of the battery container 10 is lowered.

The recess 45 is preferably provided with a plate-shaped resin molded body 2 filled with a reinforcing resin and laminated. From the viewpoint of reinforcing the shape retention, the resin molded body 2 preferably has a shape in contact with the folded portion 43a of the concave portion 45 of the side wall 43, the upper extension portion 43c, and the end extension portions 43d on both sides. .
In the first embodiment, the resin molded body 2 has a rectangular plate shape having a lower end surface on the bottom 41 side, an upper end surface on the opening side, and side end surfaces on both ends in the length direction. The main surface is in contact with the rising portion 43b, the lower end surface is in contact with the folded portion 43a, the side end surface that is the end surface in the length direction is in contact with the end extension portion 43d, and the upper end surface is in the upper extension portion 43c. Abut.
In the present specification, the “main surface” means the widest surface among a plurality of surfaces.

As the resin used for the resin molded body 2, a resin that can be used for the protective layer of the laminated film 1 can be used. The resin used for the resin molded body 2 is preferably the same as the resin of the protective layer of the laminated film 1, but may be different.
Further, since the resin used for the resin molded body 2 does not necessarily have to be bonded to the protective layer of the laminated film 1 with high adhesive strength, the resin molded body 2 molded in advance into a plate shape may be bonded with an adhesive. Good.
The thickness of the resin molded body 2 is preferably thin as long as desired shape retention is obtained. If the resin molded body 2 is thick, the battery container 10 becomes heavy, and the volumetric efficiency decreases.
The resin molded body 2 can be reduced in weight by forming a recess along the length direction of the laminated film 1 on the outer surface.

In the first embodiment, the end wall 42 of the container main body 4 shown in FIG. 1 is not reinforced with a resin plate and is substantially made of the laminated film 1.
Both ends of the end wall 42 are welded to the end extending portion 43d of the side wall 43 as shown in FIG. Thereby, the end wall 42 is fixed and connected to the side wall 43, the peripheral wall of the main body container 4 is formed, and a watertight structure is formed. Even if the end wall 42 is not reinforced with a resin plate, the shape retention of the end wall 42 is enhanced by the end extension 43d.
Since the end wall 42 is welded to the outer surface (side end surface) of the end extending portion 43d of the side wall 43 having a sufficient thickness, the deterioration of the gas barrier property at the welded portion interface is small.

As an example of the manufacturing method of the battery container 10 of the first invention, an example of manufacturing one independent container body 4 will be described with reference to FIGS. The battery container 10 according to the first invention is manufactured, for example, through the steps (1) to (4) in order as follows.
<(1) Drawing process>
As shown in FIG. 5, the recessed part 45 is formed in the both-sides side part of the laminated | multilayer film 1 by each drawing process. As a method of forming the recess 45, for example, it can be formed by performing drawing using a mold of an injection molding machine.
Further, according to the procedure as described below, after forming the concave portion 45 by the drawing molding process using the mold of the injection molding machine, the concave portion 45 is subsequently filled with the reinforcing resin and the resin molding is performed. The body 2 can be stacked (see FIGS. 6 and 8-11).
FIG. 8 is a schematic cross-sectional view showing an example of a mold of an injection molding machine used for drawing.
8 includes a male die 71 having a core 71a conforming to the inner surface shape of the recess 45, and a female die 72 having a cavity 72a conforming to the outer surface shape of the side wall 43.
A flow path 75 (sprue, runner) for guiding the molten resin 73 (see FIG. 10) supplied from the injection molding nozzle 74 is formed in the male mold 71.
A molding space 76 (see FIG. 9) is formed between the core 71a of the male mold 71 and the cavity 72a of the female mold 72.

A sliding hole 62 that slidably accommodates the pressing portion 60 is formed in the peripheral edge 78 outside the core 71a of the male mold 71. At the time of mold clamping, as shown in FIG. 9, the pressing portion 60 is urged by the pressing means 61 to insert the laminated film 1 inserted between the male mold 71 and the female mold 72 into the peripheral edge on the female mold 72 side. The portion 79 can be pressed.
The contact surface 60 a in contact with the laminated film 1 of the pressing portion 60 is preferably a smooth surface in order to reduce friction with the laminated film 1.
The core 71a of the male mold 71 can be shaped by pressing the laminated film 1 during mold clamping.

The pressing means 61 is accommodated in a pressing means accommodating space 63 formed in communication with the sliding hole 62, and the direction in which the laminated film 1 faces the male mold 71 and the female mold 72 during molding (in FIGS. 8 to 11). (Up and down direction) is suppressed.
The laminated film 1 in a state of being pressed by the pressing portion 60 is allowed to move to the molding space 76 side by a force received from the male mold 71, the resin 73, and the like. That is, the pressing force by the pressing portion 60 is within the limit of the tensile strength of the laminated film 1, and when a force stronger than this pressing force is applied to the laminated film 1, the laminated film 1 is against the pressing portion 60. Can slide.
The pressing means 61 is preferably capable of applying an elastic pressing force to the laminated film 1, and a spring, an air cylinder, or the like can be used.

  As shown in FIGS. 9 and 10, the bottom surface 62 a of the sliding hole 62 serves as a receiving seat for the pressing portion 60 during mold clamping, and restricts the retreating of the pressing portion 60 (upward movement in FIGS. 9 and 10). .

In order to mold the laminated film 1 using the mold 70, first, as shown in FIG. 8, the laminated film 1 is disposed between a male mold 71 and a female mold 72 that are separated from each other.
Next, as shown in FIG. 9, the laminated film 1 is sandwiched between the male mold 71 and the female mold 72. Thereby, a part of the laminated film 1 is pressed against the core 71a and is deformed into a concave shape along the shape of the core 71a in the molding space 76.

  As shown in FIG. 10, molten resin 73 is injected from an injection molding nozzle 74 into a molding space 76 formed between the core 71 a of the male mold 71 and the cavity 72 a of the female mold 72. Due to the injection pressure of the molten resin 73, the laminated film 1 is pushed toward the surface of the cavity 72 a of the female mold 72 and is shaped along the surface of the cavity 72 a, thereby forming the recess 45. The molten resin 73 is filled in the inner surface of the recess 45 (injection molding). In this embodiment, the molten resin 73 has a recess along the core 71a.

Since the pressing force of the pressing portion 60 is sufficiently smaller than the force that deforms the laminated film 1, the laminated film 1 that has received the pressure of the molten resin 73 is between the pressing portion 60 and the peripheral portion 79 of the female die 72. And is drawn to the molding space 76 side.
When the molten resin 73 is cooled, the molten resin 73 is cured and becomes the resin molded body 2. The resin molded body 2 is integrated with the laminated film 1.

  As shown in FIG. 11, when the female mold 72 is moved in a direction away from the male mold 71, the laminated film 1 is pushed away from the male mold 71 by the pressing portion 60, so that the laminated film 1 can be easily released. Can do.

<(2) Film notch process>
The side part including the four corners of the laminated film 1 of the laminated film 1 in which the resin molded body 2 is formed in the drawn concave parts 45 and 45 shown in FIG. As shown in FIG. 7, the side portions 43 and 43 are cut out by cutting out the unnecessary side portion 48 of FIG. 6 to the end extension portion 43d.
As a method of excising the side part of the laminated film 1, for example, a known method such as a method of punching using a punching die or a cutting using a laser beam can be employed. As shown in FIG. 7, the laminated film 1 has a side wall 43, 43, a central portion 46 that is sandwiched between the concave portions 45, 45 to become the bottom 41, and a central portion 46, by cutting away unnecessary side portions 48. And has a shape having an end wall 42 and free ends 53 and 53 to be the lead holding portion 44.
The free end 53 is a portion without the side wall 43 in the length direction of the laminated film 1.
In the present specification, the “free end” means an end that can move freely.

<(3) Concave wall and end wall rising process>
As shown in FIG. 12, the laminated film 1 is placed in a posture in which the opening of the concave portion 45 faces downward, and the laminated film 1 formed by drawing and forming the concave portions 45, 45 is the root of the folded portion 43a (the root of the central portion 46). ) Accordingly, as shown in FIG. 13, the concave wall (side wall) 43 rises on the central portion 46 that becomes the bottom 41.
And the welding layer of the folding | returning part 43a of the laminated | multilayer film 1 in which the recessed parts 45 and 45 were formed and the welding layer of the laminated | multilayer film 1 of the center part 46 are heated and welded from the bottom 41 side.
As a result, the portion including the pair of concave portions 45, 45 of the laminated film 1 becomes concave walls (side walls) 43, 43 erected so that the convex welding layers face each other (see FIG. 3).
Further, in a state where the side wall 43 shown in FIG. 13 rises on the central portion 46 that becomes the bottom 41, the free ends 53 and 53 are bent up from the root of the end extending portion 43d of the side wall 43, and are raised. Walls 42 and 42 are formed (see FIGS. 1 and 2).

<(4) Wall surface connection process>
The side edges of the formed end walls 42, 42 are overlapped with the respective end extension portions 43d of the concave walls (side walls) 43, 43, and the weld layer of the end wall 42 and the weld layer of the end extension portion 43d are joined together. Then, they are heated from the end wall 42 side and welded together.
Of the free ends 53, 53, the portions raised from the central portion 46 and having the same height as the side walls 43 become the end walls 42, 42, and the remaining portions become the lead clamping portions 44, 44. The end walls 42 and 42 are erected so that the welding layers face each other (see FIG. 2).

Then, the remaining portion of the free end 53 that extends from the end wall 42 is horizontally bent outward to form a lead clamping portion 44, and the wall surface of the end wall 42 and the side wall 43 are connected to each other by welding. As the peripheral wall of the container body 4, the battery container 10 of the first embodiment shown in FIG. 1 is obtained.
The formation of the lead holding portion 44 may be performed simultaneously with the formation of the end wall 42.

  The battery element 5 is placed in the obtained battery container 10, the lid member 3 is placed in the opening, and the upper end surface of the resin molded body 2 of the battery container 10, the lead holding portion 44, and the electrode lead 47 are covered with the lid member 3. To weld. In this way, when the electrode lead 47 is sandwiched between the lid member 3 and the lead sandwiching section 44 and the opening of the battery container 10 is closed, the film package battery 20 of the first embodiment shown in FIG. 4 is obtained.

According to the battery container and the film packaging battery manufacturing method according to the present invention, the battery container 10 and the film packaging battery 20 of the first embodiment are manufactured continuously and efficiently using the long laminated film 1. Is possible. In the present invention, the term “long” means that the length is from 1 m to 10,000 m.
Hereinafter, an example of the manufacturing method will be described with reference to FIGS.
The manufacturing method of the battery container 10 of the first embodiment performed using the long laminated film 1 is generally the same as the manufacturing method of the single independent container body 4 described above.
Hereinafter, only points different from the manufacturing method of one independent container main body 4 will be described for each process.
The manufacturing method of the battery case 10 of the first embodiment when the long laminated film 1 is used is performed through the steps (a) to (g) as follows.

<(A) Drawing process>
As shown in FIG. 14, the concave portions 45 are formed by drawing at both sides of the long laminated film 1, and the resin molded body 2 is laminated by filling the concave portions 45 with a reinforcing resin.
The formation method of the recessed part 45 is the same as the formation method of the recessed part 45 in the manufacturing method of one independent container main body 4. FIG. The method for laminating the resin molded body 2 is also the same as the method for laminating the resin molded body 2 in the independent manufacturing method of the container body 4 (see FIGS. 5 to 11).
The recessed part 45 is a part (see FIG. 15 etc.) welded to the recessed walls 43 and 43 (refer FIG. 15 etc.) adjacent to the length direction of the elongate laminated film 1 between the parts (center part 46) used as the bottom part 41. It is formed with a longer interval than the length of the side edge of the end wall 42.

<(B) Electrode opening step>
The long laminated film 1 is formed with an opening 50 (electrode lead portion) for exposing the electrode lead 47 serving as an electrode.
The opening 50 is for applying the band of the container main body 4 obtained in the wall surface connecting step, which will be described later, to the manufacturing method of the film-packed battery 20 as it is.
As a method of forming the opening 50, for example, a method of punching using a punching die or a cutting using a laser beam can be employed.
In addition, when manufacturing the film packaging battery 20 by cutting out several independent container main bodies 4 from the belt | band | zone of the container main body 4 formed in the elongate laminated film 1, the opening 50 does not need to be.
The opening 50 may be formed at any stage of the manufacturing process of the container body 4, but when the opening 50 is formed in a film notch process described later, the position of the film notch and the opening 50 becomes accurate. In addition, when the opening 50 is formed in the film notching step, the notch of the long laminated film 1 and the formation of the opening 50 are both work for cutting the film, and therefore the work becomes efficient, which is preferable.

<(C) Film notch process>
As shown in FIG. 15, in the same manner as the film notch process in the method of manufacturing one independent container body 4, a plurality of long laminated films 1 formed by drawing and forming a plurality of pairs of recesses 45, 45. A part of the side of the long laminated film 1 (unnecessary side portion 48 in FIG. 14) is cut away, leaving the pair of concave portions 45, 45 to be free ends.
As shown in FIG. 17, the long laminated film 1 from which the unnecessary side portion 48 has been cut is a center that is sandwiched between a plurality of pairs of side walls 43 and 43 and a plurality of pairs of recesses 45 and 45 to form the bottom 41. It has a shape having a portion 46 and a portion 49 that extends outward from the central portion 46 and becomes the end wall 42 and the lead clamping portion 44.

As shown in FIG. 17, a portion 49 that becomes the end wall 42 and the lead clamping portion 44 includes a connecting portion 51 having an opening 50, a lead clamping portion 44, 44, and an end wall planned portion 52 that becomes the end walls 42, 42. It consists of
Therefore, the length between the portions that become the bottom portions 41 of the plurality of container main bodies 4, that is, the lengths of the portions 49 that become the end walls 42 and 42 and the lead clamping portions 44 and 44 become the end walls 42 and 42. It is longer than the length of the portion by the length of the lead holding portions 44 and 44 and the opening 50.
The width of the connecting portion 51 and the planned end wall portion 52 is preferably equal to the width of the bottom portion 41.

With reference to FIG. 17, the shape of the elongate laminated film 1 which passed through the opening process of the electrode lead opening (electrode opening process) and the film notch process will be described in detail.
Two two-dot chain lines 1 a and 1 a extending outward from the edge of the opening 50 of the long laminated film 1 are virtual cut lines for cutting and removing the connecting portion 51. The planned cutting lines 1a and 1a divide the band in which a plurality of completed container bodies 4 or film packaging batteries 20 are connected by cutting and removing the connecting portions 51 sandwiched between the two sets of planned cutting lines 1a and 1a. The widths of the two sets of cutting lines 1a and 1a may be narrower than the width of the opening 50 as long as the connecting portion 51 can be cut and removed.
The two-dot chain line 1 b connecting the end extension portions 43 d is a boundary line between the central portion 46 that becomes the bottom portion 41 and the end wall planned portion 52. The boundary line 1 b is folded when the laminated film 1 of the planned end wall portion 52 is welded to the side wall 43 to form the end wall 42.
Further, a two-dot chain line 1c between the boundary line 1b and the planned cutting lines 1a and 1a is a boundary line between a portion to be the end wall 42 of the end wall planned portion 52 and a portion to be the lead holding portion 44. This boundary line 1c is mountain-folded when the end wall 42 is formed.
14 to 21 illustrate an example in which two continuous battery containers 10 are formed on the long laminated film 1, but usually three or more battery containers 10 are formed. The
In the first embodiment, not only the portion between the end wall planned portions 52, 52 but also the portion on the end portion side from the end wall planned portion 52 located closest to the end portion of the long laminated film 1. Is also referred to as a connecting portion 51.

<(D) Rising process of concave wall and end wall>
As shown in FIG. 16, in the same manner as the step of raising the concave wall and the end wall in the independent manufacturing method of the container body 4, the long laminated film 1 is set in a posture in which the opening of the concave portion 45 faces downward. The long laminated film 1 formed by drawing and forming a plurality of pairs of concave portions 45, 45 is bent so as to stand on the central portion 46 from the root of the folded portion 43a, thereby forming a concave wall as shown in FIG. Start up.
The folded portion 43a and the central portion 46 of the long laminated film 1 in which a plurality of pairs of concave portions 45, 45 are formed are heated and welded from the central portion 46 side. Thereby, a plurality of concave walls (side walls) 43 are formed.
In addition, the valley is vertically folded along the alternate long and two short dashes line 1b shown in FIG. 17, and the mountain is horizontally folded along the alternate long and two short dashes line 1c. The part which becomes the end wall 42 of the laminated film 1 is brought into close contact with the end extension part 43d of the concave wall (side wall) 43 to form the end wall 42 (see FIG. 19).

<(E) Wall surface connecting step> Similar to the wall surface connecting step in the independent manufacturing method of one container body 4, both side edges of the long laminated film 1 are connected to the end extending portion of the concave wall (side wall) 43. When the battery container 10 is formed by overlapping the welding layers 43d and 43d on the outer surface (both end faces) and forming a plurality of container main bodies 4 on the long laminated film 1 shown in FIG. A belt is obtained.
Moreover, if the connection part 51 of the strip | belt of the battery container 10 formed in the elongate laminated film 1 is cut off and divided, the battery container 10 of the 1st form example shown in FIG. 1 will be obtained.
Moreover, the band of the battery container 10 formed in the elongate laminated film 1 can also be used for manufacture of the film packaging battery 20 without dividing.

Next, the manufacturing method of the film packaging battery 20 performed without dividing the strip | belt of the battery container 10 formed in the elongate laminated film 1 is demonstrated.
The manufacturing method of the film packaging battery 20 of the first embodiment is obtained by adding a battery element storing step and a sealing step to the manufacturing method of the battery container 10 of the present invention. Hereinafter, the battery element storage step and the sealing step will be described.

<(F) Battery element storing step>
First, as shown in FIG. 20, the manufacturing method of the film packaging battery 20 of the first embodiment is applied to the container body 4 of each battery container 10 in the band of the battery container 10 formed on the long laminated film 1. The battery element 5 is accommodated.
When the battery element 5 is stored in the container body 4, the ends of the positive electrode lead and the negative electrode lead that protrude in opposite directions from the container body 4 of the battery container 10 are positioned in the opening 50 of the connecting portion 51. Storing as you do.

<(G) Sealing process>
As shown in FIG. 21, in the first embodiment, a long lid member 3 in which a plurality of lid members 3 are connected is used. This lid member 3 has a connecting portion 31 having an opening 30, similarly to the connecting portion 51 of the band of the battery container 10 formed on the long laminated film 1. The size of the opening 30 may be different from the connecting portion 51 of the band of the battery container 10 formed in the long laminated film 1, but is preferably the same. A plurality of independent lid members 3 can also be used.
The connecting portion 31 of the long lid 3 used in the first embodiment has the same width and length as the connecting portion 51 of the band of the container body 4 formed on the long laminated film 1 and is the same as the opening 50. Shaped openings 30 are formed at the same intervals as the openings 50. Normally, the lengths of the bands do not have to match.

The lid 3 is overlapped so that the opening 50 of the band of the battery container 10 formed in the long laminated film 1 in which the battery element 5 is housed is aligned with the opening 30 of the long lid 3. From the material 3 side, the welding layer of each lid material 3 is welded to both the welding layer of the upper extension portion 43 c of the side wall 43 of each container body 4 and the welding layer of the lead holding portion 44.
In this way, when the leads are sandwiched between the respective lid members 3 and the lead sandwiching portions 44 of the respective battery containers 10 and the openings of the respective battery containers 10 are closed, as shown in FIG. In addition, a band in which a plurality of packaging batteries 20 are formed on the long laminated film 1 is obtained.
Moreover, if the connection parts 31 and 51 of the belt | band | zone in which the several film packaging battery 20 was formed in the elongate laminated film 1 are cut and removed, the film packaging battery 20 shown in FIG. 4 will be completed.
Moreover, the belt | band | zone in which the several film packaging battery 20 was formed in the elongate laminated film 1 is good also as a finished product as it is.

The battery container 10 according to the present invention manufactured as described above is composed of the laminated film 1 in which the bottom 41 and the peripheral wall of the container body 4 include a thin metal foil, similarly to the battery container using the draw-molded container. Therefore, the battery container 10 has a high gas barrier property, is lightweight, and has a high volumetric efficiency. Moreover, unlike the battery container using the draw-molded container, the concave wall 43 constituting the peripheral wall of the container body is welded and connected to the end wall 42, so that even if the container body 4 is deep, a watertight structure is obtained. Can be formed and has excellent shape retention. Moreover, the battery container 10 can manufacture the battery container of arbitrary depths by bend | folding the laminated | multilayer film 1 containing metal foil with a fold line.
As a result, the battery container 10 according to the present invention does not need to be deeply squeezed into a three-dimensional shape even when accommodating a large-capacity thick battery element 5, so that even if the metal foil is thin, the metal foil is cracked. And pinholes do not occur.
In addition, the battery container 10 according to the present invention is a metal foil that has not been used for a draw-molded container when the thickness of the metal foil is reduced so far, or a metal foil that is not suitable for drawing because of low elongation. The laminated film used can also be used.
Further, in the battery container 10 according to the present invention, since the lid member 3 is welded to the concave wall 43, at least two opposite sides of the film-packed battery 20 are attached to the upper extending portion 43 c of the concave wall 43. Can be sealed by welding. Thereby, since the welding part of the lid | cover material 3 does not extend outside the battery container 10, a battery becomes compact and the volume of an integrated body can be made small when using several battery containers integrated. . Therefore, it is excellent in handleability when storing or accumulating a plurality of battery containers.
Moreover, since the concave wall 43 has a concave structure, the battery container 10 concerning this invention can fully enlarge the seal width at the time of welding of the cover material 3. FIG. For this reason, welding is easy and reliable, and the gas barrier property at the welded portion interface is also improved.

  Further, in the battery case 10 according to the present invention, the welded layer of the folded portion 43a of the concave wall 43 is welded to the welded layer of the bottom portion 41, so that the shape retaining property is more excellent. Further, the welded layer of the end extending portion 43d of the concave wall 43 and the welded layer on both side edges of the end wall 42 can be easily and reliably welded. Further, in the battery container 10, the concave shape 45 of the concave wall 43 is filled with the reinforcing resin and the resin molded body 2 is laminated.

  Moreover, according to the manufacturing method of the battery container 10 concerning this invention, the some container main body 4 can be formed continuously using the elongate laminated film 1. FIG. Thereby, while rewinding the long laminated film 1 wound up in a roll, bobbin winding or casket winding, or the long laminated film 1 in which the concave portion 45 is drawn, the battery container and the film packaging battery are continuously connected. Can be manufactured. Therefore, the manufacturing method of the battery container 10 according to the present invention can increase the production efficiency.

<Second embodiment>
FIG. 22 shows the battery case 110 of the second embodiment.
The battery container 110 of the second embodiment is different from the battery container 10 of the first embodiment only in that a frame body in which the central portion of the resin molded body 2 is cut out is used.
The battery container 110 according to the second embodiment can be manufactured in the same manner as the first embodiment except that the resin molded body 2 is formed to be a frame body by, for example, injection molding.
The battery container 110 of the second embodiment can be reduced in weight because the resin molded body 2 is a frame.

<Third embodiment>
FIG. 23 shows the battery case 120 of the third embodiment.
The battery container 120 of the third embodiment differs from the battery container 10 of the first embodiment only in that the length of the lower end surface of the concave wall 43 is shorter than the length of the upper end surface. .
The battery case 120 of the third embodiment is formed such that the end extension parts 43d and 43d of the concave wall 43 are inclined at an acute angle with respect to the upper extension part 43c. Thereby, the concave wall 43 is trapezoidal.
The battery case 120 of the third embodiment is the same as the first embodiment except that the concave wall 43 is formed so that the length of the folded portion 43a is shorter than the length of the upper extension portion 43c. Can be produced.

In the third embodiment, the end extending portion 43d of the concave wall 43 is inclined at an acute angle with respect to the upper extending portion 43c. Therefore, the bottom 41 of the end wall 42 is compared with the first embodiment. And the bending angle with respect to the lead clamping portion 44 is small.
Therefore, even when the rigidity of the laminated film 1 is high, peeling of the concave wall 43 and the end wall 42 from the lid member 3 hardly occurs. Therefore, the battery case 120 of the third embodiment is suitable when a highly rigid stainless steel foil is used as the gas barrier layer for the laminated film 1 and the lid material 3.
Moreover, since the opening part of the container main body 4 is wider than the bottom part 41, workability | operativity is good when accommodating the battery element 5. FIG.
In addition, since the angle of the tip formed by the upper extension portion 43c and the end extension portion 43d of the concave wall 43 is reduced, it is advantageous in sealing the lid member 3 in an airtight manner.

<Fourth embodiment>
FIG. 24 shows the battery case 130 of the fourth embodiment.
In the battery case 130 of the fourth embodiment, the end extension part 43d of the concave wall 43 has an inclination angle (inclination angle with respect to the upper extension part 43c) that is 90 as it goes from the upper extension part 43c toward the folded part 43a. Curved to be close to degrees.
In this case, since the angle of the tip formed by the upper extension portion 43c and the end extension portion 43d of the concave wall 43 is reduced, it is advantageous in sealing the lid member 3 in an airtight manner. Moreover, since the inclination angle of the end extension 43d is large at the lower part of the battery case 130, a high volume ratio can be ensured.

Or conversely, the end extension part 43d of the concave wall 43 may be curved so that the inclination angle approaches 90 degrees as it goes from the folded part 43a to the upper extension part 43c.
In addition, the concave wall 43 does not necessarily need to be formed so that both end extension parts 43d and 43d are inclined, and one of the end extension parts 43d and 43d has an acute angle with respect to the upper extension part 43c. The other may be formed perpendicular to the upper extension 43c as in the first embodiment.

As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to these form examples, In the range which does not change the summary of this invention, a various change is possible. .
As described above, in the battery containers 10, 110, 120, and 130 in the first to fourth exemplary embodiments illustrated, the resin molded body 2 is laminated on the concave portion 45 of the concave wall 43. Can be ensured, a configuration in which the resin molded body 2 is not laminated in the recess 45 is also possible.
Moreover, the shape of the resin molded body 2 is not limited to the above example, and may be a bridge shape such as two or three or more bridge piers and floor boards used in the structure of the bridge.
Furthermore, although the mode in which the positive and negative electrode leads extend in opposite directions is shown, the positive and negative electrode leads may extend from one side in the same direction.

DESCRIPTION OF SYMBOLS 1 ... Laminated film, 2 ... Resin molded object, 3 ... Cover material, 4 ... Container main body, 41 ... Bottom of (container main body), 42 ... End wall of (container main body), 43 ... Concave wall (of main body of container) (Side wall), 44 ... (the container body) lead sandwiching part, 45 ... recess, 47 ... electrode lead, 5 ... battery element, 10, 110, 120, 130 ... battery container, 20 ... film packaging battery, 50 ... opening, 70 …Mold.

Claims (5)

A battery container having a container body formed from a laminated film having a metal foil and a welding layer, and a lid ,
The peripheral wall of the container main body is formed by drawing so that the welded layer of the laminated film protrudes toward the storage portion , and has a pair of opposing surfaces that are formed with a concave portion on the outer surface and folded from the bottom of the container main body. A battery container characterized in that weld layers on both side end surfaces of the concave wall are welded and connected to weld layers on both side edges of a pair of opposing wall surfaces that are folded and raised from the bottom of the container body . Wherein the concave wall, the welding layer of the folds folded portion to the bottom portion of the container body, the battery container according to claim 1 which is welded to the welding layer of the bottom portion of the container body.   The battery container according to claim 1, wherein the concave portion of the concave wall is filled with a reinforcing resin. A film packaging battery using the battery container according to claim 1,
Accommodating the battery element to the container body, a sealed film package battery the cover material. A container body formed of a laminated film having a metal foil and a weld layer, and the peripheral wall of the container body is drawn so that the weld layer of the laminate film protrudes toward the storage section , and the outer surface Welding layers on both side edges of a pair of opposing concave walls that rise from the bottom of the container body and have recesses formed on the opposite sides of the pair of opposing walls that rise from the bottom of the container body A method of manufacturing a battery container welded and connected to a layer,
The concave walls that are adjacent to each other on both sides in the width direction of the laminated film between the portions that become the bottoms of the plurality of container main bodies that are arranged at regular intervals in the longitudinal direction of the long laminated film. A draw molding process in which a concave wall is formed by drawing a gap longer than the length of the portion welded to two opposing side surfaces;
A cutout is provided in the laminated film around the concave wall so that the width of the laminated film becomes the width of the bottom of the container body and the concave wall spreads outward as a plurality of free ends. Film notch process,
A step of raising the concave wall on the both sides of the laminated film by bending from the base of the folded portion and rising up with respect to the bottom portion of the container main body so that the respective welding layers face each other. ,
The step of standing up the end wall of the portion of the laminated film where the concave wall does not exist is bent and raised from the root of the end extension portion of the concave wall with respect to the bottom portion of the container body, and
A wall surface connecting step of overlapping both side edges of the end wall on the weld layers on both side end surfaces of the concave wall and connecting the end wall and the concave wall to form a peripheral wall of the container body. A method for producing a battery container.

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