JP2003197168A - Jacket case for battery pack and its manufacturing method, and battery pack using jacket case and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce cost and realize thin size and light weight of a jacket case of a battery pack used in cellular phones or the like. <P>SOLUTION: An embossed tape is formed by repeatedly forming recessed parts 11 in a synthetic resin tape-shaped sheet material 10 by vacuum forming, pressure forming, or a press forming. After a battery unit 3 is housed in each recessed part 11, by blanking out the sheet material 10 along a blanking line 14 enveloping the periphery of a top surface opening of the recessed part 11, the recessed part 11 is formed in a housing container part, a cover part 15 and a projection piece part 16 for exposing an outside connection terminal are integrally formed at the upper end of the housing container part. The cover part 15 is bent in the connection part of the housing container part and the upper end part, the upper end part of the housing container part and the cover part 15 are bonded on the back surface, and thereby, a case inside which the battery unit is housed is assembled. The thinner case than a case formed by conventional injection molding is provided and working time is remarkably shortened. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer case for a battery pack, a battery pack using the outer case, a method for manufacturing the outer case, and a method for manufacturing a battery pack using the outer case.

[0002]

2. Description of the Related Art As a power source for a portable electronic device such as a mobile phone, a battery pack which is detachable from the device body is used. The battery pack is a case in which a secondary battery such as a lithium ion battery and a protection circuit such as an overcharge prevention circuit are housed inside an outer case. This type of battery pack is roughly classified, for example, as disclosed in JP 2001-93496 A, a part of the outer case constitutes a part of the outer surface of the device (that is, the outer case of the battery pack is There is one that is exposed to the outside of the device) and one that the entire battery pack is housed inside the device, but in recent years, in order to commonly use the same battery pack regardless of the model change of the device,
The latter built-in type is becoming mainstream.

[0003]

The outer case of such a conventional battery pack usually forms a flat rectangular parallelepiped box body by a combination of two members made of a synthetic resin such as ABS resin. Each member is generally formed by a processing method such as injection molding or extrusion molding in which a synthetic resin melted by heating is introduced into a mold having a predetermined shape and then cooled and solidified. However, since such a molding method requires a relatively long time to mold one member, and the mold for molding is complicated, the cost required for the mold is high and the manufacturing period thereof is long. Therefore, the cost of the conventional battery pack outer case is relatively high although it is a mass-produced product, and there is a strong demand to reduce the cost.

Further, although there is a limit in reducing the wall thickness of the molded product as described above, in a battery pack for a mobile phone or a portable information terminal device, in order to reduce the thickness and weight of the device body, it is further improved. It is required to be thinner and lighter, and the thickness of the outer case is required to be thinner and lighter.

The present invention has been made to solve these problems, and an object of the present invention is to provide an outer case for a battery pack which can be made thinner and lighter at a lower cost than ever before. An object of the present invention is to provide a method for manufacturing an outer case and a battery pack using the outer case.

[0006]

An outer case for a battery pack according to the present invention made to solve the above problems accommodates a battery unit inside and exposes external connection terminals of the battery unit to the outer surface. Alternatively, in an outer case for a battery pack that has an opening for drawing out the external connection wire to the outside, a) A substantially rectangular parallelepiped box shape with the entire top surface opened, and a synthetic resin sheet material A storage container portion formed by separating a recess formed by deforming along the sheet material from the sheet material; and b) fixed to the storage container portion so as to close an upper opening of the storage container portion. It is characterized by having a lid part.

Further, in the battery pack according to the present invention made to solve the above-mentioned problems, the battery unit is housed in the housing container portion of the outer case according to the present invention, and the upper opening is formed by the lid portion. While being sealed, the external connection terminal of the battery unit is exposed to the outer surface through the opening, or the external connection wire is drawn out to the outside through the opening.

In addition, in the method of manufacturing the battery pack outer case according to the present invention, which is made to solve the above-mentioned problems, the battery unit is housed inside and the external connection terminals of the battery unit are exposed to the outside. Or a method for manufacturing an outer case for a battery pack having an opening for pulling out the external connection wire to the outside, which comprises: a) denting the sheet material by deforming a synthetic resin sheet material along a molding die. A step of forming a portion, b) a step of separating the recessed portion from the sheet material to form a substantially rectangular parallelepiped box-shaped storage container portion having an almost entire upper surface opened, and c) a sheet material formed After the battery unit is stored inside the recessed portion or the storage container portion separated from the sheet material, a sealing step of fixing the lid portion so as to close the upper opening of the battery unit is included. It

Further, a method for manufacturing a battery pack according to the present invention, which has been made to solve the above-mentioned problems, is the same as the method for manufacturing an outer case for a battery pack according to the present invention, wherein before the sealing step. After the molding step or the cutting step, a battery accommodating step of accommodating the battery unit is added to the inside of the recess formed in the sheet material or the storage container part in which the recess is separated from the sheet material. I am trying.

The forming method by "deforming along the forming die" here is, for example, placing the forming die under close or close contact with the sheet material, and pressing the sheet material against the forming die. Or, conversely, the sheet material is drawn into the forming die, or is deformed into a shape along the forming die by sandwiching it from both sides. Specifically, for example, a vacuum forming method, a compressed air forming method, a press. A molding method or the like corresponds to this.

The term "battery unit" as used herein means
As described above, in addition to the battery and the electric circuit for the battery, the battery may include only a plurality of batteries. Further, the battery is one or a plurality of primary batteries or secondary batteries, and the electric circuit includes, for example, a circuit for controlling charging and discharging of the secondary battery.

Further, in the above manufacturing method, the order of the cutting step and the sealing step is not defined, and the sealing step may be performed first, and then the cutting step may be performed.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the outer case for a battery pack and the method for manufacturing the same according to the present invention, the accommodating container portion has a recessed shape having a depth substantially equal to or slightly larger than the height of the battery unit. This shape is formed by deforming a synthetic resin sheet material along a molding die. According to this, the storage container part is formed extremely quickly, and does not require a complicated mold as in the injection molding method.
Therefore, the cost required for the molding die can be reduced, and the processing time per outer case can be significantly reduced, and at the same time, the cost can be significantly reduced. Further, since the thickness of the outer case can be reduced, the outer case itself can be made thinner than in the conventional case, and thus the weight can be reduced. Therefore, the battery pack using the outer case according to the present invention is particularly suitable for small and lightweight electronic devices such as mobile phones.

Conventionally, as disclosed in Japanese Unexamined Patent Publication No. 10-21890, there is known a battery pack in which a thin sheet material is bent to form a box-shaped outer case. With such a configuration, it is difficult to avoid sharp corners. On the other hand, in the exterior case of the present invention, the corners can be rounded like the exterior case formed by the conventional injection molding, so that it is possible to reduce the risk of the user's finger being injured when handling. There is also an advantage. Furthermore, there is an additional effect that the degree of freedom in design is high.

In the outer case for a battery pack according to the present invention, the lid may be integrated with the storage container or may be a separate body, but is preferably connected to the upper edge of the storage container. Then, the lid portion is formed, and the lid portion may close the opening of the upper surface of the storage container portion by bending in the vicinity of the connecting portion. As a manufacturing method therefor, in the cutting step, the storage container part in which the lid part is integrally connected is formed by separating the periphery of the upper surface opening of the recessed part and the lid part integrated with the same from the sheet material. In the sealing step, the upper opening of the storage container section can be closed by the lid section by bending near the connecting section.

Thus, when the concave portion is separated from the sheet material, the storage container portion and the lid portion can be obtained at the same time by separating the outer frame of the lid portion together with the concave portion from the sheet material. Therefore, it is not necessary to fabricate the lid portion separately from the storage container portion, and the manufacturing procedure can be omitted to further reduce the cost.

Further, in the battery pack outer case according to the present invention, an opening for exposing the external connection terminal of the battery unit to the outer surface or forming the external connection wire to the outside is formed in the storage container. Therefore, when forming the recessed portion in the sheet material, a portion corresponding to the opening is projected outward or inward, and when the recessed portion is separated from the sheet material, the protruding portion is cut off to form a cut-off surface. The structure may be the opening. According to this, it is possible to provide an opening of an arbitrary size at an arbitrary position on the side wall surface of the storage container portion, and it is not necessary to add a special step for providing the opening, so that the cost can be suppressed. You can

Further, when the external connection terminals of the battery unit are exposed on the outer surface, it is necessary to partition the openings so as to separate the plurality of external connection terminals, but as one mode, they are adjacent to each other. A window frame member having a partition corresponding to the gap between the external connection terminals may be fixed to the opening. As another aspect, a projecting piece corresponding to a part of the window frame member may be integrally provided on the lid, and the projecting piece may be bent and fixed to form the partitioned opening. With such a configuration, even if it is difficult to integrally form the opening in the lid by a cutting process such as punching, the window opening having the thin partition can be provided at an arbitrary position.

Various methods can be used to fix the lid portion to the storage container portion. However, at least one of the storage container portion and the lid portion is provided with an adhesive margin, and an adhesive is applied to the adhesive margin. Alternatively, a double-sided adhesive tape may be attached so that the surfaces to be in close contact with each other are fixed to each other. In this case, as one mode, the sheet material is formed in advance to have a three-layer structure in which a base layer and a protective layer are provided with a double-sided adhesive layer sandwiched therebetween, and the protective layer is removed after the storage container is formed from the sheet material. The adhesive layer may be exposed by using the adhesive layer, and the lid portion and the battery unit may be fixed by using the adhesive layer. With this configuration, it is not necessary to apply an adhesive or attach a double-sided adhesive tape to fix the lid, and the process is simplified. At the same time, since the battery unit is also fixed in the storage container portion, even if there is a gap between the outer surface of the battery unit and the inner surface of the outer case, the rattling of the battery unit is eliminated.

[0020]

The method of manufacturing a battery pack according to the first embodiment of the present invention will be described below, and the structure of the outer case of the battery pack will be described in detail.

FIG. 1 is a flow chart showing the flow of steps of the manufacturing method, FIGS. 2 and 3 are perspective views showing the assembled state of the battery pack in each step, and FIG. 4 is a battery unit housed in the outer case 1. 3 is an external perspective view of FIG. 3, and FIG.
FIG. 3 is a plan view and a front view of FIG. Here, the surface where the external connection terminals 33 of the battery unit 3 are exposed on the outer surface of the outer case 1 is referred to as the front surface.

In this manufacturing method, a sheet material made of polycarbonate resin is used as a main material of the outer case 1. As a material, in addition to workability, flame retardancy, high insulation, heat resistance, etc. are required, and other materials satisfying these conditions, for example, a synthetic resin such as PET (polyethylene terephthalate) may be used. For the reason of processing efficiency and the like, the present sheet material is, for example, a tape having a predetermined width wound in a roll shape, but it may have a wide area other than that. A sheet material having a thickness of, for example, about 0.2 mm can be used.

As a first step in manufacturing the outer case 1, a recess 11 as shown in FIG. 2A is formed in the sheet material 10 by a vacuum forming method or the like (step S1). Specifically, a molding die in which the outer shape of the recessed portion 11 is formed on the inner surface is provided in close contact with the lower portion of the sheet material 10 and the sheet material 10 is formed.
Is heated to an appropriate temperature to be softened, and the air in the gap between the mold and the sheet material 10 is sucked. Then, the softened sheet material 10 is drawn into the forming die and deformed into a shape along the inner surface of the forming die. When this is cooled and solidified, the concave portion 11 is completed. Of course, other molding methods such as a compressed air (compressed air) molding method and a press molding method may be used for molding into the same shape.

As shown in FIG. 2A, the shape of the recessed portion 11 is a shape in which a second rectangular parallelepiped 13 smaller than this is connected to one side wall surface of the first rectangular parallelepiped 12. While the tape-shaped sheet material 10 is sequentially fed, the concave portions 11 are formed one after another. Of course, a plurality of recesses 11 may be formed simultaneously in the width direction or the length direction. By such a molding process, an embossed tape having a large number of concave portions 11 formed at predetermined intervals is completed.

Next, as shown in FIG. 2B, one battery unit 3 having a substantially rectangular parallelepiped outer shape is housed in each recess 11 of the embossed tape (step S2).
As shown in FIG. 4, the battery unit 3 has a flat rectangular parallelepiped lithium-ion secondary battery 31 and a control circuit 32 integrated with each other, and an external connection terminal (in this example, an external connection terminal) is provided on one end surface of the control circuit 32. 3) 33 are exposed. The control circuit 32 includes, for example, an overcharge prevention circuit, an overdischarge prevention circuit,
It includes a temperature fuse cutoff circuit for abnormal heat generation, a temperature monitoring control circuit including a thermistor, and a charge timer circuit. The inner height of the recess 11 is formed to be substantially the same as or slightly larger than the height of the battery unit 3. Therefore, the upper surface of the battery unit 3 housed in the recess 11 is substantially flush with or slightly lower than the upper surface of the sheet material 10.

Next, for each part corresponding to one exterior case 1 including the recessed part 11 in which the battery unit 3 is housed,
The sheet material 10 along the punching line 14 shown in FIG.
Is punched out (step S3). In consideration of such punching, the adjacent recessed portion 1 at the time of the above-mentioned molding is performed.
The interval of 1 is fixed. After being punched in this way, one member has a shape shown in FIG.

That is, a portion of the concave portion 11 corresponding to the second rectangular parallelepiped 13 is cut off to form a large cutout portion 18 that hangs down from the upper edge of the box-shaped storage container portion 17 whose entire upper surface is open. Further, a lid portion 15 extending in a tongue shape is connected to the upper edge of the wall surface facing the wall surface in which the cutout portion 18 is formed. Furthermore, three notches 16a are formed on the edge of the lid 15 on the side opposite to the connection with the storage container 17.
The projecting piece portion 16 in which is formed is formed.

Incidentally, at the time of punching (or another independent process may be used), the storage container portion 17 and the lid portion 15 are formed.
Bending lines may be added to the connecting points (first bending line described below) and the connecting points (second bending line described below) between the lid portion 15 and the projecting piece portion 16, respectively.

Further, by the above punching, the storage container portion 1
A collar portion 19 is formed at an upper edge of the longitudinal direction 7 to spread outward. Next, the double-sided adhesive tape 2 is attached to the upper surface of the collar portion 19.
0 is adhered (step S4). In addition, the storage container part 17
The double-sided adhesive tape 21 is also adhered to the periphery of the notch portion 18. 5A and 5B are a top plan view and a front plan view showing a state in which the double-sided adhesive tapes 20 and 21 are attached.

Then, as shown in FIG. 3B, the lid 1
5, the back surface (lower surface when folded) of the lid portion 15 is along the first bending line L1 and is the collar portion 19 of the storage container portion 17.
Bend until it touches. Further, the projecting piece 16 is bent along the second bending line L2 until it comes into contact with the outside of the side wall surface provided with the cutout portion 18 of the storage container portion 17 (step S).
5). Since the double-sided adhesive tapes 20 and 21 are attached to the portions facing the bent surfaces, the bent surfaces are fixed to the facing surfaces by the adhesiveness of the double-sided adhesive tapes 20 and 21, whereby the lid portion 15 is formed. Is the storage container section 17
In addition to closing the upper surface opening, the projecting piece portion 16 closes the cutout portion 18 while forming three window openings 22.

FIGS. 5C and 5D are a top plan view and a front plan view showing the state of the outer case 1 at this time. The outer case 1 has a flat rectangular parallelepiped shape as a whole, and has three window openings 22 that are separated from each other by a cross section of the sheet material 10 at a position corresponding to the external connection terminal 33 of the battery unit 3. Therefore, the external connection terminals 33 of the battery unit 3 are exposed in the window openings 22, respectively.

As described above, the battery pack having the battery unit 3 inside and the outer case 1 in which only the external connection terminals 33 of the battery unit 3 are exposed to the outside is completed.

The order of some of the above steps can be changed as appropriate. For example, before the battery unit 3 is housed in the recessed portion 11, the members corresponding to one outer case are separated (punched), and then the battery unit 3 is housed in each housing container portion 17. Good.

The outer case 1 described in the first embodiment can be modified into various forms. The modification will be described below.

In the first embodiment, the lid 15 and the projecting piece 16 for forming the window opening 22 are integrated with the storage container 17, but one or two of them are used. A member different from the storage container unit 17 is provided, and the storage container unit 1 will be used later.
It may be configured to be fixed to 7.

FIG. 6 is a top plan view and a front plan view of the outer case 1 according to the second embodiment. In FIG.
(A) and (B) are top plan views and front plan views showing a state immediately after punching from the sheet material 10, and (C) and (D) are top plan views and front views showing a state after being bent into a predetermined shape. A plan view, (E) is a front plan view of a window forming member 23 which is a member different from the above member.

In the second embodiment, instead of providing the collar portion at the upper edge of the storage container portion 17, as shown in FIGS. A bent piece 15a is provided. A double-sided adhesive tape (not shown) is attached to the upper surface of the bent piece 15a (the upper surface in the state before being bent), and the tape is bent inward along the third bending line L3 to the upper side wall surfaces of the storage container portion 17. Can be pasted. On the other hand, in order to form the window opening 22, a window forming member 23, which is a member different from the lid portion 15, is prepared and attached to the periphery of the opening portion 16b formed by bending the projecting piece portion 16. Thereby, the three window openings 22 separated from each other can be formed.

That is, in any of the outer casings 1 of the first and second embodiments, formation of the storage container portion 17 by vacuum forming or pressure forming along a forming die, separation by punching, bending, etc. are involved. By fixing the lid portion, the outer case 1 having a substantially rectangular parallelepiped shape containing the battery unit 3 can be assembled.

Further, in this type of battery pack, one surface of the double-sided adhesive tape is adhered to the inner bottom portion of the outer case and the battery unit is adhered to the opposite side so that the battery unit does not rattle in the outer case. Although it may be attached, the battery unit 3 can be more easily fixed by adopting the following configuration.

That is, as the sheet material 10 for forming the storage container portion 17, as shown in FIG. 7A, the resin base film 10a made of polycarbonate or the like is used as the lowermost layer, and the adhesive layer 10b is provided as the intermediate layer. As the uppermost layer, a sheet material 10 having a three-layer structure having a protective separation film 10c is used.
Then, for example, the recessed portion 11 is formed according to the manufacturing procedure as described in the first embodiment (see FIG. 7B), and the recessed portion 11 and the lid portion 15 are separated from the sheet material 10 (see FIG. 7C). )reference). After that, the protective separation film 10c on the entire surfaces of the separated storage container portion 17 and lid portion 15 is peeled off. Then, the inner surface of the storage container portion 17 and the back surface of the lid portion 15 (the back surface when assembled as the outer case 1) all become the adhesive layer 10b. Therefore, the battery unit 3 should be stored in the storage container portion 17 in that state. Accordingly (see FIG. 7D), the battery unit 3 has the adhesive layer 10 inside the storage container portion 17.
Since there is no backlash due to being stuck to b, and the adhesive layer 10b is also exposed at the contact surface between the lid portion 15 and the storage container portion 17, the lid portion 15 and the protruding piece portion 16 can be stuck as they are. (See FIG. 7E).

In the above embodiment, the double-sided adhesive tapes 20 and 21 are used as a method for fixing the lid 15 and the protruding piece 16.
Although the pressure-sensitive adhesive layer 10b and the pressure-sensitive adhesive layer 10b are used, various other fixing methods can be used. For example,
A method using an adhesive or a method using heat welding may be used.

The external connection terminal 33 of the battery unit 3
The window opening 22 for exposing the battery to the outer surface may be provided at an appropriate position according to the battery unit 3 housed inside. Depending on the type of the battery unit 3, the external connection line (cable line) may be drawn out instead of the planar external connection terminal 33, and a connector or the like may be provided at the end thereof. In such a case, as described above, the window opening 22 provided with the crosspiece that separates the external connection terminals from each other.
In addition, the structure becomes simpler because it is only necessary to provide a simple opening through which the external connection line can be led out.

Further, in the above embodiment, the procedure for manufacturing a battery pack in units of one unit has been described. However, in the case of mounting such a battery pack inside a device in an assembly factory of a mobile phone or the like, for example, It is desirable to deliver to the assembly plant in a form that can be easily handled by an automatic mounting device or the like. For example, as one form thereof, a recessed portion as described in the first embodiment is continuously formed on a tape-shaped sheet material, and a battery unit is housed inside each recessed portion, and then the upper surface opening of each recessed portion is opened. And seal it so that it is covered with another sheet material.
As a result, a so-called embossed carrier tape in which a large number of battery packs in which the battery units are housed in the outer case are connected is completed. However, the normal embossed carrier tape is only a temporary container for transporting electronic components and mounting components, but the embossed carrier tape of this battery pack is for protecting the battery unit during transportation, or In addition to being a container for easy handling, they are individually separated during packaging to form an outer case. Therefore, the cost of individual battery packs can be reduced, and the cost of mounting on a device can be reduced.

In addition to the above description, it is obvious that the present invention can be variously modified and modified. For example, the type of battery housed inside is not limited. Further, the material and the like of the members forming the outer case are not limited.

[Brief description of drawings]

FIG. 1 is a flowchart showing a manufacturing procedure of a battery pack outer case according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an assembled state in each step of manufacturing the battery pack outer case according to the first embodiment.

FIG. 3 is a perspective view showing an assembled state in each step in manufacturing the battery pack outer case according to the first embodiment.

FIG. 4 is an external perspective view showing an example of a battery unit housed in an outer case for a battery pack according to the present invention.

FIG. 5 is a top plan view and a front plan view of the battery pack outer case according to the first embodiment.

6A and 6B are a top plan view and a front plan view of an outer case for a battery pack according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view showing an assembled state in each step of manufacturing an outer case for a battery pack according to still another embodiment of the present invention.

[Explanation of symbols]

1 ... Exterior case 3 ... Battery unit 31 ... Lithium-ion secondary battery 32 ... Control circuit 33 ... External connection terminal 10 ... Sheet material 10a ... Resin base film 10b ... Adhesive layer 10c ... Protective separation membrane 11 ... Recess 12 ... 1st rectangular parallelepiped 13 ... Second rectangular parallelepiped 14 ... Perforated line 15 ... Lid 15a ... bent piece 16 ... Projection part 16a ... notch 16b ... opening 17 ... Storage container part 18 ... Notch 19 ... Tsubabe 20, 21 ... Double-sided adhesive tape 22 ... Window opening 23 ... Window forming member L1, L2, L3 ... Bending line

Claims (9)

[Claims] 1. An outer case for a battery pack, which accommodates a battery unit inside and has an opening for exposing the external connection terminal of the battery unit to the outer surface or for pulling out the external connection wire to the outside, a) A substantially rectangular parallelepiped box shape in which the entire upper surface is substantially open, and a storage container portion formed by separating a recess formed by deforming a synthetic resin sheet material along a molding die from the sheet material. And b) a lid part fixed to the storage container part so as to close an upper surface opening of the storage container part. 2. The lid is formed so as to be connected to the upper edge of the storage container, and the lid closes the upper opening of the storage container by bending in the vicinity of the connection. The outer case for a battery pack according to claim 1, wherein 3. When forming a recessed portion in the sheet material,
The portion corresponding to the opening is projected outward or inward,
The outer case for a battery pack according to claim 1 or 2, wherein, when the concave portion is separated from the sheet material, the projecting portion is cut off so that a cut-off surface serves as the opening portion. 4. A window frame member having a partition corresponding to a gap between adjacent external connection terminals in the battery unit is fixed to the opening in accordance with the opening. The outer case for a battery pack according to any one of 1 to 3. 5. A projecting piece corresponding to a window frame part having a partition corresponding to a gap between adjacent external connection terminals in the battery unit is integrally provided on the lid part, and the projecting piece is bent to form the projecting piece. The outer case for a battery pack according to any one of claims 1 to 3, wherein the outer case is fixed according to the opening. 6. The sheet material has a three-layer structure in which a base layer and a protective layer are provided in advance with a double-sided adhesive layer sandwiched therebetween, and the protective layer is removed after the storage container is formed from the sheet material. The exterior case for a battery pack according to claim 1, wherein the adhesive layer is exposed to expose the adhesive layer, and the adhesive layer is used to fix the lid portion and the battery unit. 7. The battery unit is housed in the housing container portion of the outer case according to claim 1, the upper opening is sealed by the lid portion, and the external connection terminal of the battery unit is opened. The battery pack is characterized in that it is exposed to the outside through the external connection line or is drawn out to the outside through the opening. 8. A method of manufacturing an outer case for a battery pack, which accommodates a battery unit inside thereof and has an opening for exposing the external connection terminal of the battery unit to the outside or for drawing out the external connection wire to the outside. Then, a) a molding step of forming a recess in the sheet material by deforming a synthetic resin sheet material along a molding die, and b) separating the recess portion from the sheet material and A cutting step of forming a substantially rectangular parallelepiped box-shaped storage container portion, and c) the battery unit is stored inside the recess formed in the sheet material or the storage container portion separated from the sheet material. And a sealing step of fixing a lid part so as to close the opening of the upper surface thereof. 9. The method for manufacturing an outer case for a battery pack according to claim 8, wherein a recess formed in the sheet material after the forming step or the cutting step before the sealing step,
Alternatively, a method for manufacturing a battery pack is characterized in that a battery accommodating step of accommodating the battery unit is added inside the accommodating container part in which the recess is separated from the sheet material.