JP5036239B2 - Battery pack and manufacturing method thereof - Google Patents

Description

  The present invention relates to a chargeable / dischargeable nonaqueous electrolyte secondary battery, specifically a lithium ion secondary battery, which is mainly used as a power source for portable electronic devices such as a video camera, a mobile computer, a mobile phone, etc. The present invention relates to a battery pack housed in a container and a manufacturing method thereof.

  In recent years, as power sources for portable electronic devices such as video cameras, mobile computers, and mobile phones, which are rapidly spreading, chargeable / dischargeable rectangular parallelepiped nonaqueous electrolyte secondary batteries such as lithium ion secondary batteries are mainly used. It has been. BACKGROUND ART A lithium ion secondary battery is configured such that a power generation element in which a positive electrode and a negative electrode are wound via a separator is made of aluminum or an aluminum alloy and housed in a rectangular parallelepiped case.

  On the side surface of the lithium ion secondary battery (unit cell), a circuit wiring unit having an external output terminal and including a protection circuit board and a lead plate for controlling the battery voltage to prevent overcharge and overdischarge is disposed. Thus, an assembled battery is configured. The assembled battery is attached to an electronic device as a battery pack in which at least a side surface is covered with an insulating outer body made of, for example, a synthetic resin. The protective circuit board and the unit cell are electrically connected by the lead plate.

Patent Document 1 discloses an invention of a battery pack in which a circuit wiring portion is coated on a side surface of a unit cell by resin molding.
Patent Document 2 discloses an invention of a method for manufacturing a battery pack in which assembled batteries are housed in various cylindrical cases, and resin is filled and sealed from the opening of the case.

In Patent Document 3, the circuit wiring part is positioned with respect to the side surface of the unit cell while the protective circuit board is held by the molding holder, and a resin molding part (exterior body) is formed so as to cover the circuit wiring part by insert molding. An invention of a battery pack and a method for manufacturing the battery pack is disclosed.
In Patent Document 4, a claw portion is provided on a protective circuit board, and the circuit wiring portion is covered with a resin by filling the mold with a resin in a state where the capping portion holds the circuit wiring portion in a molding die. An invention of a battery pack for forming a resin molded portion and a method for manufacturing the same is disclosed.

Patent Document 5 discloses a battery pack in which a protective circuit board is positioned in a mold by positioning pins provided in the mold, and then the mold is filled with a resin to form a resin molding portion that covers a circuit wiring portion. And an invention of its manufacturing method is disclosed.
In Patent Document 6, an assembled battery is movably stored in a mold, a protective circuit board is positioned by injection pressure when filling the resin, and then the mold is filled with resin to cover the circuit wiring portion. An invention of a battery pack for forming a resin molded part and a manufacturing method thereof is disclosed.
In Patent Document 7, the top cover on which the protective circuit board is positioned is fitted into the opening of the unit cell having the upper and lower ridges, and the top cover is placed on the same surface as the surface on which the external output terminal of the protective circuit board is located. An invention of a battery pack in which a resin is injected from a provided resin injection hole, and the inside of a top cover is filled and cured, and a method for manufacturing the same are disclosed.
JP 2000-315483 A JP 2002-134077 A JP 2003-17022 A JP 2003-229105 A JP 2003-288872 A JP 2004-362873 A JP 2005-166644 A

  In the case of the battery pack of Patent Document 1, as pointed out in detail in Patent Document 3, it is difficult to accurately place the protective circuit board in the mold and mold the resin. It is unsuitable for the structure installed in the molding part, and is suitable for a battery pack for connecting a connector having an external output terminal at the tip of a lead wire to an assembled battery. This battery pack has a drawback that the lead wire is easily disconnected.

  Many examples of the battery pack of Patent Document 2 are shown. However, since each of the battery packs has a structure in which the assembled battery is housed in a cylindrical case, there is a problem that there is a limit to downsizing.

Patent Documents 3 to 6 all describe a method for preventing the external output terminal portion of the protective circuit board from being covered with the filled resin, but what is common is that the mold is used. The protruding portion provided is abutted against the surface of the external output terminal portion, thereby preventing the resin from entering the surface. In this structure, the convex portion is required to have heat resistance, wear resistance, and insulation, but materials satisfying the required performance are limited to ceramics and fluororesins.
Ceramics and fluorine-based resins are expensive, and there is a problem that the cost of mold parts increases. Furthermore, since ceramic is very hard and has poor processability, it is difficult to process with high precision, and fine irregularities and corners may remain after processing. For this reason, there is a problem in that when the projection is abutted against the external output terminal portion during molding, the external output terminal portion is frequently damaged. Further, since the fluororesin does not have sufficient wear resistance required for mold parts, it has a problem that it wears out early and the resin wraps around the surface side of the external output terminal portion.

  In any of the battery pack manufacturing methods of Patent Documents 3 to 5, in order to prevent the external output terminals from being covered with the filled resin, each of the protection circuit boards including the external output terminals is molded. Although it is held by a holder, a claw portion provided on the substrate, and a movable pin that protrudes into the molding chamber at the time of molding, a hollow shape remains in the protective circuit board holding portion in the molded resin portion after molding (Patent Documents 3 and 5) ), Since the nail portion is exposed on the upper surface of the resin molded portion (Patent Document 4), there is a problem that the appearance is not good.

Each of the battery packs of Patent Documents 3 to 5 is characterized in that a resin molded portion made of a filled resin forms an exterior of the battery pack. In such a battery pack, polyamide, polyurethane, and the like are generally used as resins that can be molded at low temperatures and low pressures. These resins are polycarbonates (PC) that are conventionally used as an outer package of a battery pack. , Acrylonitrile butadiene styrene (ABS), and PC / ABS, which is a synthetic material thereof, have poor mechanical strength. For this reason, there is a problem that the resin molded part may be broken by a drop impact, or may be worn by being attached to or detached from the mobile phone to expose the inside of the battery pack.
Polyamide, polyurethane, etc. are usually transparent with a tortoiseshell color, or translucent with a milky white color, and the resin molded parts molded with these resins can be seen through the internal parts, so that the concealability In order to increase the color, a colorant was added in advance to adjust the color to a color such as black. For this reason, there is a problem that not only the cost is increased but also the material becomes brittle due to the influence of the colorant and the fluidity is deteriorated.

  Patent Documents 3 and 5 describe a structure for holding a protection circuit board having an external output terminal. However, this structure is complicated and there is a problem that the cost of a mold is increased.

  In the method of Patent Document 6, since the protective circuit board is positioned by the injection pressure when filling the resin, not only the resin injection port is limited, but the resin is filled so as to surround the entire side surface of the unit cell. There is a problem that there is a limit to downsizing of the battery pack.

  Each of the battery packs of Patent Documents 1 to 6 has a structure in which the resin molding portion forms a part of the battery pack outer package. In such a structure, when the assembled battery is put into and out of the mold, it is inevitable that the battery contacts with the mold, the protective circuit board is scraped off and the substrate is scraped and remains in the mold. For this reason, there is a problem that foreign matters remaining in the substrate scrap and the mold may appear on the surface of the resin molded portion, resulting in a defective appearance.

  In the battery pack manufacturing method of Patent Document 7, since the resin is injected from the resin injection port provided on the same surface as the surface where the external output terminal of the top cover is provided, the resin is also passed through the internal protection circuit board. If the hole is not opened, there is a problem that the resin does not go around to the back side of the substrate. Therefore, the wiring space of the protection circuit board is limited, and it is necessary to take measures such as multilayering of the board, resulting in a problem that the cost of the protection circuit board increases. Further, there is a problem that burrs are easily generated on the surface after resin molding due to metal wear or the like, the surface does not become flat, and the connection with the mobile phone becomes unstable.

  The present invention has been made in view of such circumstances, and at least one resin injection hole is provided in a side surface covering body that covers the side surface of the assembled battery, and the side surface covering body contains resin from the resin injection hole. By being configured to be connected to the side surface of the assembled battery in a filled and cured state, the resin does not appear, so the color is not limited, and it is not necessary to perform toning beforehand, and as a material for the side surface covering body PC, ABS, PC / ABS, etc. can be used, so it has excellent mechanical strength such as drop strength and wear resistance, and the mold structure is simple and the cost can be reduced. It is an object of the present invention to provide a battery pack having a good appearance and a manufacturing method thereof, in which foreign matter remaining inside does not appear on the surface of a side surface covering after molding.

  Further, according to the present invention, the surface on which the resin injection hole is provided is different from the terminal exposed surface, or the resin injection hole has an axis substantially parallel to the plane of the protection circuit board. It is not necessary to provide a hole through which the resin flows in the protective circuit board, and burrs after resin molding due to wear of the mold or the like are formed at the connecting portion between the side surface covering body and the side surface of the assembled battery. An object of the present invention is to provide a battery pack that is easily generated and does not occur on a terminal exposed surface, and is flat, so that the connection state with a main device such as a mobile phone is well maintained.

  And this invention suppresses that an external output terminal is covered with resin filled by having a holding part which contacts a surface which has an external output terminal of a protection circuit board to a terminal exposure surface, An object of the present invention is to provide a battery pack capable of simplifying the structure of the mold and reducing the cost of the mold, and a manufacturing method thereof.

  Furthermore, an object of this invention is to provide the battery pack which can be shape | molded at low temperature and low pressure by using a polyamide-type resin or a polyurethane-type resin as resin, and its manufacturing method.

  Further, according to the present invention, the side surface covering body is a box-shaped body having an opening on one side, and is connected to the side surface in a state where the opening edge portion on the one side is in close contact with the peripheral edge portion on one side surface of the assembled battery. An object of the present invention is to provide a battery pack that can be reduced in size by being configured.

The battery pack according to the onset Ming, the side surface of the unit cell constituting a rectangular parallelepiped having two planar and opposing sides, arranged circuit wiring portion including a protection circuit board having an external output terminal, and the lead plate, the lead An assembled battery formed by connecting the protection circuit board and a terminal of the unit cell via a plate, and a terminal exposed surface having a window part for exposing the external output terminal, and includes the circuit wiring part. In the battery pack including the side surface covering body that covers the side surface, the side surface covering body is provided with at least one resin injection hole, and the side surface covering body is made of resin filled inside from the resin injection hole. It is connected to the side surface of the assembled battery in a cured state.

The battery pack of the present invention has a configuration in which a resin is filled in and molded into a side surface covering body as an exterior body. As a material for the side surface covering body, a PC used for a conventional battery pack exterior body, Since ABS, PC / ABS, and the like can be used, they are excellent in mechanical strength such as drop strength and wear resistance.
And even if the resin with which the inside is filled is transparent or translucent, it is covered with the side surface covering body, so that the internal parts do not show through. Therefore, the color of the resin is not limited, and there is no need to perform color matching beforehand.
Further, in the present invention, since the side surface of the assembled battery is covered with the side surface covering body, the resin is filled only inside thereof, so that a convex portion is provided on the mold with ceramic and fluororesin, etc. There is no need to hit it. Accordingly, the structure of the mold is simple, the cost can be reduced, and the surface of the external output terminal can be prevented from being damaged, and the resin can be suppressed from entering the surface side.
And since it is the structure which fills the inside of a side surface covering body, the foreign material which remained in metal molds, such as a substrate scrap, does not appear on the surface of a side surface covering body after a shaping | molding, but an external appearance is favorable. .

The battery pack according to the present onset Ming, surface pre Symbol resin injection holes are provided, characterized in that it is a surface different from the said terminal exposed surfaces.

  When the surface on which the resin injection hole is provided is the same surface as the terminal exposed surface, it is necessary to provide a hole through which the resin flows in the protection circuit board in order to fill the resin to the back side of the protection circuit board. In the present invention, since the surface on which the resin injection hole is provided is a surface different from the terminal exposed surface, it is not necessary to provide the hole on the protection circuit board. Further, even when burrs are generated after resin molding due to die wear or the like, the burrs are mainly generated at the connecting portion between the side surface covering and the side surface of the assembled battery, and are not generated on the terminal exposed surface. The surface is flat, and the connection state with the main device such as a mobile phone can be well maintained.

The battery pack according to the present onset Ming, before Symbol resin injection hole, characterized in that the axis is substantially parallel to the plane of the protection circuit board.

  In the present invention, since the resin injection hole is provided so that the axis is substantially parallel to the plane of the protection circuit board, it is not necessary to provide a hole for allowing the resin to flow through the protection circuit board. In addition, even if burrs are generated after resin molding due to mold wear, etc., the burrs are mainly generated at the connecting portion between the side surface covering and the side surface of the assembled battery, and not on the terminal exposed surface. The connection state with the device can be maintained well.

The battery pack according to the present onset Ming, before SL side surface covering member, the surface having the external output terminal of the protection circuit board being in contact with the said terminal exposed surfaces, to hold the protection circuit board It has a holding part.

In the present invention, the filled resin is prevented from going around the surface and covering the external output terminal.
And like a conventional battery pack, a hollow shape does not remain in the holding part after molding, and the holding part is formed inside the side surface covering body and is not exposed to the outer surface of the side surface covering body. So the appearance is good.
Further, since the resin is filled from the resin injection hole of the side surface covering body with the protective circuit board held by the holding portion, the mold structure is simple and the mold cost can be reduced. .

  In the present invention, molding is possible at low temperature and low pressure.

The battery pack according to the present onset Ming, before SL side is one side, the side surface covering member is a box-shaped body, one side of which is an opening, the peripheral edge portion of the side surface of the opening edge portion of said one surface It is characterized by being connected to the side surface in a state of being in close contact with the surface.

  In the present invention, since the side cover does not protrude in the thickness direction of the battery pack, the battery pack can be downsized.

The manufacturing method of the present onset Ming battery pack, the side surface of the unit cell constituting a rectangular parallelepiped having two planar and opposing sides, distribution circuit wiring portion including a protection circuit board having an external output terminal, and a lead plate In the battery pack manufacturing method including the step of connecting the protection circuit board and the unit cell terminal via the lead plate to obtain a battery pack, a terminal exposed surface having a window portion for exposing the external output terminal A side surface covering process that includes the circuit wiring portion and covers the side surface of the assembled battery, and a side surface covering body that includes at least one resin injection hole on a surface different from the terminal exposed surface. The process of installing the assembled battery with the side surface covered by the mold in the mold, the process of injecting the resin from the resin injection hole and filling the resin in the side surface covering body, and the process of curing the filled resin And Characterized in that it.
The manufacturing method of the present onset Ming battery pack, the side surface of the unit cell constituting a rectangular parallelepiped having two planar and opposing sides, distribution circuit wiring portion including a protection circuit board having an external output terminal, and a lead plate In the battery pack manufacturing method including the step of connecting the protection circuit board and the unit cell terminal via the lead plate to obtain a battery pack, a terminal exposed surface having a window portion for exposing the external output terminal A side surface covering step including the circuit wiring portion and covering the side surface of the assembled battery by a side surface covering body provided with at least one resin injection hole whose axis is substantially parallel to the plane of the protective circuit board. , A process of installing the assembled battery whose side surface is covered by the side surface covering body in a mold, a process of injecting resin from the resin injection hole, and filling the inside of the side surface covering body, and filling Cure resin And having a process of.
Further, the production method of the present onset Ming battery pack, the side surface of the unit cell constituting a rectangular parallelepiped having two planar and opposing sides, distribution circuit wiring portion including a protection circuit board having an external output terminal, and a lead plate In the battery pack manufacturing method including the step of connecting the protection circuit board and the unit cell terminal via the lead plate to obtain a battery pack, a terminal exposed surface having a window portion for exposing the external output terminal And including at least one resin injection hole and a side cover that is a box-shaped body with one side open, and includes an opening edge on one side of the side cover and the circuit wiring part . From the resin injection hole, a side surface covering process for covering the side surfaces so as to be connected in close contact with each other, a process of installing the assembled battery whose side surface is covered by the side surface covering body in the mold, and Before injecting resin And having a step of filling the resin into the inside of the side surface covering member, and a step of curing the filled resin.

In the present invention, since the battery pack is manufactured by filling the inside of the side surface covering body as the exterior body, the material of the side surface covering body is PC or ABS used for the exterior body of the conventional battery pack. , And PC / ABS can be used, and a battery pack excellent in mechanical strength such as drop strength and wear resistance can be obtained.
Further, in the present invention, since the side surface of the assembled battery is covered with the side surface covering body, the resin is filled only inside thereof, so that a convex portion is provided on the mold with ceramic, fluorine resin, or the like, and the external output terminal is provided. There is no need to hit it. Accordingly, the cost of the mold can be reduced, and the surface of the external output terminal can be prevented from being damaged, and the resin can be prevented from flowing out to the external output terminal side in the process of filling the resin. It is.
And since resin is filled in the inside of the side surface covering body, the foreign matter remaining in the mold such as substrate scraps does not appear on the surface of the side surface covering body after molding, and the appearance is good.

Method for producing a battery pack of the present invention, the prior SL side surface covering member, in a state in which the surface having the external output terminal of the protection circuit board is brought into contact with the terminals exposed surfaces, holding for holding the protection circuit board The side surface covering step is a step of covering the side surface of the assembled battery with the side surface covering body in a state where the protection circuit board is held by the holding portion.

In the present invention, the filled resin is prevented from going around the surface of the protective circuit board having the external output terminals and covering the external output terminals.
And, unlike the conventional method of manufacturing a battery pack, no concave shape remains in the holding portion after molding, and the holding portion is formed inside the side surface covering body and exposed to the outer surface of the side surface covering body. Because it is not, the appearance is good.
Furthermore, since the battery pack is manufactured by filling the resin from the resin injection hole of the side surface covering body with the protective circuit board held in the holding portion, the mold structure is simple and the mold cost is reduced. I can do it.

  According to the present invention, at least one resin injection hole is provided in the side surface covering body that covers the side surface of the assembled battery, and the side surface covering body is in a state where the resin filled inside from the resin injection hole is cured. Since the resin is not exposed, the color of the resin is not limited and it is not necessary to perform color matching in advance. PC, ABS, PC / ABS, etc. can be used as the material for the side surface covering body, and the mechanical strength such as drop strength and abrasion resistance is excellent, and the cost of the mold can be reduced. The foreign matter remaining in the mold does not appear on the surface of the side surface covering after molding, and the appearance is good.

  According to the present invention, the surface on which the resin injection hole is provided is a surface different from the terminal exposed surface, or the resin injection hole has an axis substantially parallel to the plane of the protection circuit board. By providing as such, there is no need to provide a hole through which the resin flows in the protective circuit board, and even if burrs occur after resin molding due to wear of the mold, etc., it does not occur on the exposed terminal surface. Since the surface is flat, a battery pack can be obtained in which the connection state with the main device such as a mobile phone is well maintained.

  And according to this invention, since it has a holding part which contacts the surface which has an external output terminal of a protection circuit board to a terminal exposure surface, it is suppressed that an external output terminal is covered with resin with which it filled up. The mold structure can be simplified and the mold cost can be reduced.

  Furthermore, according to the present invention, since a polyamide-based resin or a polyurethane-based resin is used as the resin filled in the side surface covering body, it can be molded at a low temperature and a low pressure.

  Further, according to the present invention, the side surface covering body is a box-shaped body having an opening on one surface, and the opening edge portion on the one surface is connected to the side surface in a state of being in close contact with the peripheral edge portion on one side surface of the assembled battery. Therefore, the thickness of the assembled battery and the height of the side surface covering body substantially coincide with each other, and the battery pack can be reduced in size.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
Embodiment 1 FIG.
FIG. 1 is a perspective view showing a battery pack 1 according to Embodiment 1 of the present invention, and FIG. 2 is an exploded perspective view showing the battery pack 1.
The unit cell 21 of the assembled battery 2 of the battery pack 1 has a rectangular plate shape, and includes a non-aqueous electrolyte secondary battery including a power generation element in which a positive electrode and a negative electrode are wound via a separator, specifically, for example, A secondary battery such as a lithium ion secondary battery, in which a power generation element is housed in a case made of aluminum or aluminum alloy. A negative electrode terminal 21a is provided at the center of one side surface of the unit cell 21 via an insulating plate (not shown), and a positive electrode terminal 21b is provided adjacent to the negative electrode terminal 21a.

  A double-sided adhesive double-sided tape 24 is affixed to the side of the unit cell 21 opposite to the side where the positive electrode terminal 21 b is provided. An insulating plate 23 is attached to the double-sided tape 24 in a state where the negative electrode terminal 21a is exposed from the exposure window 23a.

The circuit wiring portion 22 includes a protection circuit board 22a, a first lead plate 22d, and a second lead plate 22e.
A circuit element 22b for preventing overcharge or overdischarge of the unit cell 21 is mounted on the surface of the protection circuit board 22a facing the unit cell 21, and the opposite side, that is, the outer side, is connected to the outside. Positive and negative external output terminals 22c, 22c and 22c for taking out electric power and taking in electric power from outside for charging are provided by gold plating.

A protective element 22f is attached to the first lead plate 22d. One end portion of the first lead plate 22d is spot welded to the electrode of the protection circuit board 22a, and the other end portion is spot welded to the negative electrode terminal 21a in contact with the insulating plate 23. Examples of the protective element 22f include a single element or a composite element selected from the group consisting of PTC, fuse, and bimetal. The electrode of the protective circuit board 22a and the negative electrode terminal 21a may be directly connected by the first lead plate 22d without using the protective element 22f.
One end of the second lead plate 22e is spot welded to the electrode of the protection circuit board 22a, and the other end is spot welded to the positive terminal 21b.
The protection circuit board 22a is electrically connected to the unit cell 21 via the first lead plate 22d and the second lead plate 22e, whereby the assembled battery 2 is configured.

For example, the side surface covering 3 made of PC, ABS, PC / ABS, or the like is connected to the side surface of the unit cell 21 while covering the circuit wiring portion 22. As the material of the side surface covering 3, a reinforcing material to which about 10 to 30% of glass fibers are added may be used in order to improve resistance to the resin filled inside.
FIG. 3 is a perspective view of the side cover 3 as seen from the back side.
The side surface covering 3 has a terminal exposed plate portion (terminal exposed surface) 31 having windows 31a, 31a, 31a for exposing the external output terminals 22c, 22c, 22c, an upper plate portion 32, and a lower plate portion 33. A box having a single-sided opening, in which a first side plate portion 34 and a second side plate portion 35 are provided.
Near the opening of the first side plate portion 34, a resin injection hole 34a for injecting resin is provided.

At both ends in the longitudinal direction of the lower plate portion 33 near the terminal exposed plate portion 31, substantially triangular prism-shaped holding portions 33 a and 33 a extending in the longitudinal direction are projected. A substantially triangular prism-shaped holding portion 32 a extending in the longitudinal direction is suspended from a substantially central portion of the upper plate portion 32 near the terminal exposed plate portion 31. The protection circuit board 22a is held by the holding portions 32a, 33a, and 33a while being in contact with the terminal exposed plate portion 31.
The shape of the holding portions 32a, 33a, 33a is not limited to a substantially triangular prism shape, and the cross-sectional shape may be a rectangle, a trapezoid, a semicircle, or the like. Further, the holding portions 32a, 33a, 33a are not limited to the above-described configuration, and are provided at least one place above and below the side surface covering body 3 so that the protective circuit board 22a contacts the terminal exposed plate portion 31. That's fine.
The side surface covering body 3 covers the circuit wiring portion 22 and the resin is filled into the internal space from the resin injection hole 34a, and the resin is hardened to form a resin molding portion 4 (see FIG. 4) described later. Is generated and bonded to the side surface of the unit cell 21.

Below, the manufacturing method of the battery pack of this Embodiment is demonstrated.
First, one end of each of the first lead plate 22d and the second lead plate 22e is spot welded to the electrode of the protection circuit board 22a.
Then, the insulating plate 23 is fixed to the side surface of the unit cell 21 having the negative electrode terminal 21 a with a double-sided tape 24.
Next, the other end portions of the first lead plate 22d and the second lead plate 22e attached to the protection circuit board 22a are spot-welded to the negative terminal 21a and the positive terminal 21b, respectively.
One end portions of the first lead plate 22d and the second lead plate 22e are bent by 180 °, and the protective circuit board 22a is arranged so that the external output terminals 22c, 22c, and 22c are substantially parallel to the side surface of the unit cell 21.
Further, the side cover 3 is placed on the circuit wiring portion 22 in a state where the protection circuit board 22a is held in contact with the terminal exposed plate portion 31 by the holding portions 32a, 33a, 33a.
Then, the assembled battery 2 whose side surface is covered with the side surface covering 3 is mounted on the mold.

4 is a partial longitudinal sectional view showing a state in which the assembled battery 2 is mounted on the mold 5, and FIG. 5 is a plan sectional view showing a state in which the assembled battery 2 is mounted on the mold 5.
The mold 5 includes an upper mold 51 and a lower mold 52. The assembled battery 2 whose side surface is covered with the side surface covering 3 is closely attached to an upper mold 51 and a lower mold 52.
A polyamide resin having a softening point of 195 ° C. is heated to approximately 220 ° C. and melted, and the gap between the side cover 3 is filled through the sprue 53 and the runner 54 through the resin injection hole 34a. The holding pressure for injection is 0.3 MPa. In addition, a polyurethane resin or the like can be used as the resin, and any resin that can be molded at a low temperature and a low pressure may be used.
Since the protection circuit board 22a is brought into contact with the back surface of the terminal exposed plate part 31 by the holding parts 32a, 33a, 33a, the resin is a surface on which the external output terminals 22c, 22c, 22c of the protection circuit board 22a are provided. The space on the side where the circuit element 22b is provided is filled. The filled resin is cured to form the resin molded portion 4, and the side surface covering 3 is bonded to the side surface of the assembled battery 2.

In the manufacturing method of the present embodiment, the protection circuit board 22a is held in advance in the side cover 3 by holding portions 32a, 33a, 33a provided in the side cover 3. Since it is the structure which fills the inside of the side surface covering body 3 and molds it with the side surface of the unit cell 21 covered, the structure of the mold 5 can be simplified and the cost of the mold 5 is reduced. I can do it.
And the resin molding part 4 is not the exterior body of the battery pack 1, but is formed inside the side surface covering body 3 as the exterior body. Will not show through. Therefore, the color of the resin is not limited, and it is not necessary to perform toning in advance.
Moreover, as the material of the side surface covering body 3, since PC, ABS, PC / ABS, etc. which were used for the exterior body of the conventional battery pack can be used, the battery pack 1 has the drop strength and the wear resistance. Excellent mechanical strength.

  Furthermore, since the mold is not configured to have a convex portion made of ceramic, fluorine resin, or the like and abut against the external output terminals 22c, 22c, 22c, the external output terminals 22c, 22c, 22c are damaged during molding, The resin does not wrap around the external output terminals 22c, 22c, and 22c. The foreign matter remaining in the mold such as substrate scrap does not appear on the surface of the side surface covering 3 after molding, and the appearance of the obtained battery pack 1 is good.

  Since the resin is filled in the state where the protection circuit board 22a is held by the holding portions 32a, 33a, and 33a at the time of molding, the external output terminals 22c, 22c, and 22c are prevented from being covered with the filled resin. In addition, no concave shape remains in the holding portions 32a, 33a, and 33a after molding, and the holding portions 32a, 33a, and 33a are not exposed on the outer surface of the side surface covering body 3, so that the appearance is good.

Further, since the resin injection hole 34a is provided in the first side plate portion 34 different from the terminal exposed plate 31, it is not necessary to provide a hole for allowing the resin to flow through the protective circuit board 22a, and the burr is mainly formed on the side surface. Since it occurs in the connecting portion between the cover 3 and the side surface of the unit cell 21 and not in the terminal exposed plate portion 31, the surface of the terminal exposed plate portion 31 is flat, and the connection state with the main body device such as a mobile phone is set. It can be held well.
Further, the obtained battery pack 1 has the side cover 3 having the opening having substantially the same shape as the side face of the unit cell 21 and connected to the side face. The battery 2 does not protrude in the thickness direction and can be reduced in size.

  In the above-described embodiment, the case where the resin injection hole is provided in the first side plate portion 34 has been described. However, the present invention is not limited to this and may be provided in another plate portion. Is not limited to one. However, when it is provided in the terminal exposed plate portion 31, it is necessary to provide a hole through which the resin flows in the protection circuit board 22a. Therefore, the wiring space of the protection circuit board 22a is limited, and the protection circuit board 22a is multilayered. Therefore, it is preferable that the protective circuit board 22a is provided on a plate portion other than the terminal exposed plate portion 31.

Embodiment 2. FIG.
6 is a perspective view showing a battery pack 11 according to Embodiment 2 of the present invention, and FIG. 7 is an exploded perspective view showing the battery pack 11. In the figure, the same parts as those in FIG. 1 and FIG.

The circuit wiring part 25 of the battery pack 11 according to the present embodiment is horizontally provided on the surface of the unit cell 21 having the negative electrode terminal 21a.
The circuit wiring part 25 includes a protection circuit board 25a, a first lead plate 25d, and a second lead plate 25e.
A circuit element 25b for preventing overcharge or overdischarge of the unit cell 21 is mounted on the back surface of the protection circuit board 25a. On the front side, power is taken out to the outside, and conversely for charging. Positive and negative external output terminals 25c, 25c, 25c for taking in electric power from the outside are provided by gold plating.

A protective element 25f is attached to the first lead plate 25d. One end of the first lead plate 25d is spot-welded to the electrode of the protection circuit board 25a, and the other end is spot-welded to the negative electrode terminal 21a in contact with the insulating plate 23. Examples of the protective element 25f include a single element or a composite element selected from the group consisting of PTC, a fuse, and a bimetal. The electrode of the protective circuit board 25a and the negative electrode terminal 21a may be directly connected by the first lead plate 25d without using the protective element 25f.
One end of the second lead plate 25e is spot welded to the electrode of the protection circuit board 25a, and the other end is spot welded to the positive electrode terminal 21b.
The protection circuit board 25a is electrically connected to the unit cell 21 via the first lead plate 25d and the second lead plate 25e, whereby the assembled battery 2 is configured.

For example, the side surface covering 6 made of PC, ABS, PC / ABS, or the like is connected to the side surface of the unit cell 21 in a state where the circuit wiring portion 25 is covered. As a material of the side surface covering 6, a reinforcing material to which about 10 to 30% of glass fibers are added may be used in order to improve resistance to the resin filled inside.
FIG. 8 is a perspective view of the side cover 6 as seen from the back side.
The side surface covering 6 has a terminal exposed plate portion (terminal exposed) having window portions 62a, 62a, and 62a for exposing the external output terminals 25c, 25c, and 25c to the side surface facing plate portion 61 that faces the side surface of the unit cell 21. Surface) 62, a lower plate portion 63, a first side plate portion 64, and a second side plate portion 65.

Resin injection holes 61 a and 61 a for injecting resin are provided at both ends of the side facing plate portion 61. On the back surface of the side facing plate portion 61, a holding portion 61b is provided that extends in the longitudinal direction of the side facing plate portion 61 and on which the end portion on the side facing plate portion 61 side of the protection circuit board 25a is placed.
Holding portions 63a and 63a that extend in a direction orthogonal to the longitudinal direction and support the protection circuit board 25a from below are provided on both end sides of the lower plate portion 63 near the side facing plate portion 61 in the longitudinal direction. .
The protection circuit board 25a is held by the holding portions 61b, 63a, and 63a in contact with the terminal exposed plate portion 62.
The side surface covering body 6 covers the circuit wiring portion 25 and is filled with a resin inside the resin injection holes 61a and 61a. The resin is cured and adhered to the side surface of the unit cell 21. Yes.

Below, the manufacturing method of the battery pack 11 of this Embodiment is demonstrated.
First, one end of each of the first lead plate 25d and the second lead plate 25e is spot welded to the electrode of the protection circuit board 25a.
Then, the insulating plate 23 is fixed to the side surface of the unit cell 21 having the negative electrode terminal 21 a with a double-sided tape 24.
Next, the other end portions of the first lead plate 25d and the second lead plate 25e attached to the protection circuit board 25a are spot-welded to the negative terminal 21a and the positive terminal 21b, respectively.
One end portions of the first lead plate 25d and the second lead portion 25e are bent by 90 °, and the protective circuit board 25a is arranged so that the external output terminals 25c, 25c, 25c are substantially parallel to the plane of the unit cell 21.
Further, the side cover 6 is placed on the circuit wiring portion 25 in a state where the protective circuit board 25a is held in contact with the terminal exposed plate portion 62 by the holding portions 61b, 63a, 63a.
The assembled battery 2 whose side surface is covered with the side surface covering body 6 is attached to the mold.

FIG. 9 is a partial longitudinal sectional view showing a state in which the assembled battery 2 is mounted on the mold 8.
The mold 8 includes an upper mold 81 and a lower mold 82. The assembled battery 2 whose side surface is covered with the side surface covering body 6 is tightly attached to an upper mold 81 and a lower mold 82.
A polyamide-based resin having a softening point of 195 ° C. is heated to approximately 220 ° C. and melted, and the gap between the side cover bodies 6 is filled through the sprue 83 and the runner 84 through the resin injection holes 61a and 61a. . The holding pressure for injection is 0.3 MPa. In addition, a polyurethane resin or the like can be used as the resin, and any resin that can be molded at a low temperature and a low pressure may be used.
Since the protection circuit board 25a is in contact with the back surface of the terminal exposed plate part 62 by the holding parts 61b, 63a, 63a, the resin is a surface on which the external output terminals 25c, 25c, 25c of the protection circuit board 25a are provided. The space on the side where the circuit element 25b is provided is filled. The filled resin is cured to form the resin molded portion 7, and the side surface covering 6 is adhered to the side surface of the assembled battery 2.

In the manufacturing method of the present embodiment, the protection circuit board 25 a is held in advance in the side surface covering body 6 by holding portions 61 b, 63 a, 63 a provided in the side surface covering body 6. The structure of the side cover 6 is filled with a resin while the side surface of the unit cell 21 is covered, so that the structure of the mold 8 can be simplified and the cost of the mold 8 can be reduced. I can do it.
And the resin molding part 7 is not the exterior body of the battery pack 11, but is formed in the inside of the side surface covering body 6 as the exterior body. There is no see-through. Therefore, the color of the resin is not limited, and it is not necessary to perform toning in advance.
Moreover, as the material of the side surface covering body 6, since PC, ABS, PC / ABS, etc. which were used for the exterior body of the conventional battery pack can be used, the battery pack 11 has a drop strength and wear resistance. Excellent mechanical strength.

  In addition, since the mold is not configured to have a convex portion made of ceramic, fluorine resin, or the like and abut against the external output terminals 25c, 25c, 25c, the external output terminals 25c, 25c, 25c are damaged during molding, The resin does not wrap around the external output terminals 25c, 25c, 25c. And the foreign material which remained in metal molds, such as a substrate scrap, does not appear on the surface of the side surface covering body 6 after shaping | molding, but the external appearance of the side surface covering body 6 obtained is favorable.

  In addition, since the resin is filled in the state where the protective circuit board 25a is held by the holding portions 61b, 63a, and 63a at the time of molding, the external output terminals 25c, 25c, and 25c are prevented from being covered with the filled resin. In addition, no concave shape remains in the holding portions 61b, 63a, and 63a after molding, and the holding portions 61b, 63a, and 63a are not exposed on the outer surface of the side surface covering body 63, so that the appearance is good.

Further, since the resin injection holes 61a and 61a are provided in the side facing plate portion 61 different from the terminal exposed plate 62, it is not necessary to provide a hole in the protection circuit board 25a, and the burr is mainly used for the side surface covering 6. Occurs at the connection portion between the battery cell 21 and the side surface of the unit cell 21 and does not occur at the terminal exposed plate portion 62. Therefore, the surface of the terminal exposed plate portion 62 is flat and maintains a good connection state with the main device such as a mobile phone. I can do it.
Further, the obtained battery pack 11 has the side surface covering body 6 in which the side surface covering body 6 is connected to the side surface with the opening having substantially the same shape as that of the side surface of the unit cell 21. The battery 2 does not protrude in the thickness direction, and is downsized.

  In the above embodiment, the case where the resin injection hole is provided in the side facing plate portion 61 is described. However, the present invention is not limited to this and may be provided in another plate portion. Is not limited to one. However, when it is provided in the terminal exposed plate portion 62, it is necessary to provide a hole through which the resin flows in the protective circuit board 25a. Therefore, the wiring space of the protective circuit board 25a is limited, and the protective circuit board 25a is multilayered. Therefore, it is preferable that the protective circuit board 25a is provided on a plate portion other than the terminal exposed plate portion 62.

It is a perspective view which shows the battery pack which concerns on Embodiment 1 of this invention. It is a disassembled perspective view which shows a battery pack. It is the perspective view which looked at the side surface covering body from the back side. It is a partial longitudinal cross-sectional view which shows the state which mounted | wore the assembled battery with the metal mold | die. It is a plane sectional view showing the state where an assembled battery was attached to a metallic mold. It is a perspective view which shows the battery pack which concerns on Embodiment 2 of this invention. It is a disassembled perspective view which shows a battery pack. It is the perspective view which looked at the side surface covering body from the back side. It is a partial longitudinal cross-sectional view which shows the state which mounted | wore the assembled battery with the metal mold | die.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,11 Battery pack 2 Assembly battery 21 Unit cell 21a Negative electrode terminal 21b Positive electrode terminal 22, 25 Circuit wiring part 22a, 25a Protective circuit board 22b, 25b Circuit element 22c, 25c External output terminal 22d, 25d 1st lead board 22e, 25e Second lead plate 22f, 25f Protective element 23 Insulating plate 24 Double-sided tape 3, 6 Side cover 31, 62 Terminal exposed plate portion 32 Upper plate portion 33, 63 Lower plate portion 34, 64 First side plate portion 34a, 61b Resin injection Hole 32a, 33a, 61b, 63a Holding part 35, 65 Second side plate part 61 Side facing plate part 4, 7 Resin molding part 5, 8 Mold

Claims (8)

On the side surface of the unit cell having a rectangular parallelepiped shape having two opposing flat surfaces and side surfaces,
An assembled battery comprising a protective circuit board having an external output terminal, and a circuit wiring portion including a lead plate, and connecting the protective circuit board and the terminal of the unit cell via the lead plate;
In the battery pack, comprising: a terminal exposed surface having a window portion that exposes the external output terminal; and a side surface covering that includes the circuit wiring portion and covers a side surface of the assembled battery.
The side surface covering body is provided with at least one resin injection hole,
The side surface covering body is connected to the side surface of the assembled battery in a state where the resin filled inside from the resin injection hole is cured ,
The battery pack is characterized in that the surface on which the resin injection hole is provided is a surface different from the terminal exposed surface . On the side surface of the unit cell having a rectangular parallelepiped shape having two opposing flat surfaces and side surfaces,
An assembled battery comprising a protective circuit board having an external output terminal, and a circuit wiring portion including a lead plate, and connecting the protective circuit board and the terminal of the unit cell via the lead plate;
In the battery pack, comprising: a terminal exposed surface having a window portion that exposes the external output terminal; and a side surface covering that includes the circuit wiring portion and covers a side surface of the assembled battery.
The side surface covering body is provided with at least one resin injection hole,
The side surface covering body is connected to the side surface of the assembled battery in a state where the resin filled inside from the resin injection hole is cured ,
The battery pack , wherein the resin injection hole has an axis substantially parallel to a plane of the protection circuit board . On the side surface of the unit cell having a rectangular parallelepiped shape having two opposing flat surfaces and side surfaces,
An assembled battery comprising a protective circuit board having an external output terminal, and a circuit wiring portion including a lead plate, and connecting the protective circuit board and the terminal of the unit cell via the lead plate;
In the battery pack, comprising: a terminal exposed surface having a window portion that exposes the external output terminal; and a side surface covering that includes the circuit wiring portion and covers a side surface of the assembled battery.
The side surface covering body is provided with at least one resin injection hole,
The side surface covering body is connected to the side surface of the assembled battery in a state where the resin filled inside from the resin injection hole is cured ,
The side surface is one side surface,
The side cover is a box-shaped body having an opening on one side, and the battery pack is connected to the side in a state where the opening edge of the one side is in close contact with the peripheral edge of the side .   The said side surface covering body has a holding part which hold | maintains this protection circuit board in the state which contact | abutted the surface which has the said external output terminal of the said protection circuit board in contact with the said terminal exposure surface. The battery pack described in 1. A protective circuit board having an external output terminal and a circuit wiring portion including a lead plate are arranged on the side surface of the unit cell having a rectangular parallelepiped shape having two opposing flat surfaces and side surfaces, and the protective circuit board and the above-mentioned through the lead plate In a method for manufacturing a battery pack including a process of obtaining a battery pack by connecting a terminal of a unit cell,
The assembly includes the circuit wiring portion by a side surface covering provided with a terminal exposed surface having a window portion for exposing the external output terminal and having at least one resin injection hole on a surface different from the terminal exposed surface. A side coating process covering the side of the battery;
Installing the assembled battery whose side surface is covered with the side surface covering body in a mold;
Injecting resin from the resin injection hole, filling the resin inside the side cover,
A process for producing a battery pack, comprising: curing a filled resin. A protective circuit board having an external output terminal and a circuit wiring portion including a lead plate are arranged on the side surface of the unit cell having a rectangular parallelepiped shape having two opposing flat surfaces and side surfaces, and the protective circuit board and the above-mentioned through the lead plate In a method for manufacturing a battery pack including a process of obtaining a battery pack by connecting a terminal of a unit cell,
The circuit wiring includes a terminal covering surface having a window portion for exposing the external output terminal, and a side surface covering body provided with at least one resin injection hole whose axis is substantially parallel to a plane of the protective circuit board. A side surface covering process that includes a portion and covers the side surface of the assembled battery;
Installing the assembled battery whose side surface is covered with the side surface covering body in a mold;
Injecting resin from the resin injection hole, filling the resin inside the side cover,
A process for producing a battery pack, comprising: curing a filled resin. A protective circuit board having an external output terminal and a circuit wiring portion including a lead plate are arranged on the side surface of the unit cell having a rectangular parallelepiped shape having two opposing flat surfaces and side surfaces, and the protective circuit board and the above-mentioned through the lead plate In a method for manufacturing a battery pack including a process of obtaining a battery pack by connecting a terminal of a unit cell,
An opening edge of one surface of the side surface covering body is provided by a side surface covering body which is a box-shaped body provided with a terminal exposure surface having a window portion for exposing the external output terminal, provided with at least one resin injection hole, and having one surface opened. A side surface covering process that covers the first and second peripheral edges of the assembled battery in close contact with each other, and the circuit wiring portion.
Installing the assembled battery whose side surface is covered with the side surface covering body in a mold;
Injecting resin from the resin injection hole, filling the resin inside the side cover,
A process for producing a battery pack, comprising: curing a filled resin. The side surface covering body has a holding portion for holding the protection circuit board in a state where the surface of the protection circuit board having the external output terminal is in contact with the terminal exposed surface.
The battery pack according to any one of claims 5 to 7 , wherein the side surface covering step is a step of covering the side surface of the assembled battery with the side surface covering body in a state where the protection circuit board is held by the holding portion. Production method.

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