JP2003077434A - Battery pack and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent inner pressure from rising by operating a safety valve properly while protecting the safety valve. SOLUTION: This battery pack is equipped with a battery 2 having a safety valve 21 which opens when its inner pressure gets higher than a set pressure, and a resin molding part 1 formed by insert molding the cell 2. The resin molding part 1 has a resin intrusion blocking part 9 to block intrusion of synthetic resin molding the resin molding part 1. The battery pack forms an exhaust path which communicates the safety valve 21 with the outside of the resin molding part 1 in the resin intrusion blocking part 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery pack and a method for manufacturing the battery pack, and more particularly, to a battery pack in which a battery is temporarily fixed in a molding chamber of a mold and is connected to the battery to form a plastic resin molding portion. The manufacturing method is related.

[0002]

2. Description of the Related Art A battery pack has been developed in which an outer case of a battery pack is used as a resin molding part and the battery is insert-molded and fixed when molding the resin molding part. Insert molding is performed in the molding chamber of the mold that molds synthetic resin.
The battery, the printed circuit board, and the like are temporarily fixed, and the synthetic resin injected into the molding chamber is temporarily fixed and the battery and the printed circuit board are molded so as to be in close contact with each other. Therefore, the battery and the printed circuit board can be integrally fixed to the molded resin molding portion. This method has a feature that the battery or the printed circuit board can be firmly fixed in place when the resin molding part is molded. It is possible to omit the assembly process of storing the battery and the like in a fixed position in a separately molded plastic case. That is, since molding and fixing can be performed at the same time, there is a feature that mass production can be performed inexpensively and efficiently. The battery pack manufactured by this method is described in JP-A-2000-315483. As shown in FIG. 1, this battery pack has a printed circuit board 5 and a battery 2 when a resin molding part which becomes an outer case is molded.
Is temporarily fixed to the molding chamber 11 of the mold 10 and a molten synthetic resin is injected into the molding chamber 11. In this battery pack, the printed circuit board 5 and a part of the battery 2 are insert-molded and fixed to the resin molding portion. Unlike conventional battery packs, this battery pack does not require the battery and printed circuit board to be separately assembled in a case, and is a process of molding a resin molding part that corresponds to the case. Can be fixed in place.

[0003]

However, in the battery pack having this structure, it is more difficult to normally operate the safety valve than the conventional battery pack in which the battery is housed in a separately molded case. The old battery pack, which contains the battery in a separately molded case, opens when the battery safety valve opens.
The gas discharged from the safety valve can be discharged inside the case. The gas discharged to the case passes through the gap of the case and is discharged to the outside. Therefore, in the battery pack having this structure, the safety valve can operate normally. However, in a battery pack manufactured by insert molding a printed circuit board or the like in a resin molding portion, it is difficult to quickly exhaust the gas discharged from the opened safety valve. This is because the gap between the resin molded part and the battery becomes narrow and gas cannot pass smoothly. Therefore, when the internal pressure of the battery rises, the safety valve cannot be opened to quickly prevent the internal pressure of the battery from rising. This adverse effect can be eliminated by fixing the resin molding portion to the portion without the safety valve. However, in the battery pack of this structure, the opening of the safety valve is exposed to the outside, so the safety valve may be accidentally destroyed from the outside. Since the safety valve is made weak so that it is easily broken by the internal pressure, if a needle-shaped foreign substance comes into contact with the safety valve, it will be broken and cannot be used as a battery pack.

The present invention was developed for the purpose of solving such drawbacks. An important object of the present invention is to provide a battery pack and a method of manufacturing the battery pack, in which the safety valve can be operated accurately while the internal pressure of the battery is reliably prevented while protecting the safety valve.

[0005]

The battery pack of the present invention comprises:
A battery 2 having a safety valve 21 that opens when the internal pressure of the battery 2 becomes higher than a set pressure, and a plastic resin molding part 1 formed by insert molding the battery 2 are provided. The resin molding portion 1 has a resin intrusion prevention portion 9 that prevents invasion of the synthetic resin that molds the resin molding portion 1. In this battery pack, the resin intrusion prevention portion 9 forms a discharge path for connecting the safety valve 21 to the outside of the resin molding portion 1.

Further, the battery pack according to claim 2 of the present invention has a battery 2 having a safety valve 21 that opens when the internal pressure of the battery 2 becomes higher than a set pressure, and the battery 2 is fixed at a fixed position. And a plastic resin molding part 1 made of plastic that insert-molds the holder 4 and the battery 2 to fix the holder 4 to the battery 2. Holder 4
Has a resin intrusion prevention portion 9 for preventing intrusion of the synthetic resin forming the resin molding portion 1. In the battery pack, the resin intrusion prevention portion 9 forms a discharge path that connects the safety valve 21 to the outside. This battery pack has a convex electrode 2B of the battery 2.
It is possible to provide the safety valve 21 on the end surface of the electrode having the and to fix the holder 4 and the resin molding portion 1 to the end surface of the electrode.
Further, in this battery pack, the holder 4 that connects the printed circuit board 5 to a fixed position can be insert-molded and fixed to the resin molding portion 1.

Further, in the battery pack of the present invention, the temperature protection element 6 can be arranged in the resin intrusion prevention section 9.
The temperature protection element 6 can be a PTC or a thermal fuse. Furthermore, in the battery pack, the surface of the battery 2 can be exposed to the resin intrusion prevention part 9 so that the temperature protection element 6 arranged in the resin intrusion prevention part 9 can be brought close to the battery 2.

The method of manufacturing a battery pack according to the present invention includes a battery 2
Safety valve 21 that opens when the internal pressure of the valve becomes higher than the set pressure
Temporarily hold the battery 2 having the following in the molding chamber 11 of the mold 10,
In the molding chamber 11 of the mold 10, the resin molding portion 1 is molded on the end surface of the battery 2 where the safety valve 21 is provided. Furthermore, the manufacturing method according to the present invention is applied to the molding chamber 1 in which the battery 2 is temporarily fixed.
When the resin molding part 1 is molded with 0, a resin intrusion prevention part 9 for preventing intrusion of a synthetic resin in a molten state for molding the resin molding part 1 is provided, and the resin invasion prevention part 9 causes the safety valve 21 to be exposed to the outside. A communicating discharge path is formed.

Further, the manufacturing method of claim 9 of the present invention is
In addition to the battery 2, a holder 4 having a resin intrusion prevention portion 9 for preventing intrusion of a molten synthetic resin for molding the resin molding portion 1 is temporarily fixed to a molding chamber 11 for molding the resin molding portion 1 by resin. The molding portion 1 is molded, and the resin intrusion prevention portion 9 forms a discharge path for communicating the safety valve 21 to the outside. Further, according to this manufacturing method, the temperature protection element 6 is provided in the resin intrusion prevention portion 9 of the holder 4, and the holder 4 is temporarily fixed to the molding chamber 11 of the mold 10 and is melted in the molding chamber 11 of the mold 10. The resin molding part 1 can be molded by injecting the synthetic resin of.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. However, the examples described below exemplify the battery pack and its manufacturing method for embodying the technical idea of the present invention, and the present invention does not specify the battery pack and its manufacturing method as follows. .

Further, in this specification, in order to facilitate understanding of the claims, the numbers corresponding to the members shown in the embodiments are referred to as "the claims column" and "to solve the problems. It is added to the members shown in "Means column".
However, the members shown in the claims are not limited to the members of the embodiment.

In the battery pack shown in FIGS. 2 to 6 and 11, the resin molding portion 1 is molded and fixed to the peripheral portion of the battery 2. The battery pack of FIGS. 2 to 6 has the resin molding portion 1 fixed to the electrode end surface where the convex electrode 2B of the battery 2 is provided, and the battery pack of FIG. 11 has resin molding on three sides including the electrode end surface. The part 1 is fixed. As shown in FIGS. 7 and 8 and FIGS. 12 to 14, the resin molding portion 1 includes a holder 4
The temperature protection element 6 is fixed by insert molding.
7, FIG. 12, FIG. 12, and FIG. 13 show a battery pack in which the resin molding portion 1 is not molded in order to make the holder 4 incorporated in the resin molding portion 1 easy to see. 8 and 13 show perspective views in which the parts are disassembled.

The battery pack shown in these figures is the battery 2
A temperature protection element 6 connected to the battery 2, a printed circuit board 5 on which a protection circuit is mounted, a holder 4 for fixing the printed circuit board 5 and the temperature protection element 6 in place, and the holder 4 for the battery 2 The resin molding part 1 connected to the.

The battery 2 is a rechargeable secondary battery such as a lithium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery or the like. The battery 2 in the figure is a thin prismatic battery, and has a shape in which both sides of the outer can 2A have curved surfaces and four corners of the outer can 2A are chamfered. Using a lithium-ion battery for the thin prismatic battery has the feature that the charging capacity relative to the capacity of the entire battery pack can be increased. In this battery 2, a safety valve 21 is provided on a sealing plate 2C located on the electrode end surface on which the convex electrode 2B is provided. In the battery 2 shown in the figure, the convex electrode 2B is provided at the center of the sealing plate 2C, and the safety valve 21 is provided at one end. The battery may have a safety valve built in the convex electrode. The safety valve 21 opens when the internal pressure of the battery 2 becomes higher than the set pressure. The opened safety valve 21 discharges internal gas and the like to stop the rise of the internal pressure of the outer can 2A. The safety valve 21 is a rupture film 22 that is airtightly adhered to the opening of the sealing plate 2C. The breaking film 22 is broken when the internal pressure of the battery 2 reaches the set pressure, and the safety valve 21 is opened. The breaking film 22 is a metal foil, a laminated film of a metal foil and a plastic film, a plastic film, or the like so as to be broken at a set pressure. Instead of a rupture film, the safety valve may have a structure in which a part of the outer can is thinly processed to make it easier to break. Further, as the safety valve built in the convex electrode, as shown in FIG. 16, one having a structure in which the valve body 28 is pressed against the valve seat 29 by the elastic body 27 can be used. The safety valve 21 opens when the valve body 28 is pushed by the internal pressure and discharges gas or the like from the discharge hole 30.

The printed circuit board 5 is mounted with electronic parts for realizing a protection circuit for the battery 2. In the battery pack shown in this figure, the protection circuit is mounted on the printed circuit board 5, but the protection circuit may be provided as a small IC in the resin molding portion. This battery pack can omit the printed circuit board. Furthermore, in the battery packs of FIGS. 4 and 11, the output terminal 3 is fixed to the printed circuit board 5.

In the battery pack, the temperature protection element 6 and the printed circuit board 5 are temporarily fixed to an accurate position of the mold and the resin molding part 1 is provided.
The holder 4 for insert molding and fixing is provided at a fixed position. The holder 4 is molded of plastic separately from the resin molding part 1. The holder 4 is insert-molded and fixed to the resin molding portion 1 together with the battery 2. That is, the holder 4 and the battery 2 are temporarily fixed to a mold for molding the plastic resin molding part 1, and the molten synthetic resin is injected into the molding chamber of the mold to mold the resin molding part 1.
The holder 4 and the battery 2 temporarily fixed in the molding chamber are partially embedded in the resin molding portion 1 and fixed.

In the battery pack shown in the figure, the holder 4 is insert-molded in the resin molding portion 1 with the printed circuit board 5 and the temperature protection element 6 being held in place. The battery pack is
The holder 4 or the resin molding portion 1 is provided with a resin intrusion prevention portion 9 that prevents intrusion of the synthetic resin that molds the resin molding portion 1. The resin intrusion prevention portion 9 forms a discharge path that connects the safety valve 21 to the outside of the resin molding portion 1. This discharge path discharges gas and electrolyte discharged from the opened safety valve 21 and further fragments of contents such as electrode plates and separators to the outside. The battery pack shown in FIGS. 7 and 8 has a holder 4
A resin invasion preventing portion 9 is provided on the. The resin invasion preventing portion 9 has one end (the right end in the drawing) opened, and the safety valve 21
The opening of is communicated with the outside. The resin intrusion prevention section 9
It is not always necessary to provide the holder 4. As shown in FIG. 11, the resin molding part 1 may be provided with a resin intrusion prevention part 9. The battery pack has an opening beside the resin molding portion 1 (upper surface in the drawing) so that the opening portion of the safety valve 21 communicates with the outside.

As shown in FIGS. 7 and 8, the resin intrusion prevention section 9 may be provided with the temperature protection element 6. The temperature protection element 6 is an element that is connected in series with the battery 2 and interrupts current when the battery 2 becomes higher than a set temperature, and is a PTC or a thermal fuse. The temperature protection element 6 does not necessarily have to be arranged in the resin intrusion prevention portion 9 that communicates the opening of the safety valve 21 with the outside. As shown in FIG. 14, the battery pack of FIG. 11 is provided with two resin intrusion prevention parts 9 and one of the resin intrusion prevention parts 9 forms a discharge path for communicating the safety valve 21 to the outside, and the other resin intrusion prevention part 9 is formed. The temperature protection element 6 is provided in the blocking unit 9.
Are installed. The resin intrusion prevention part 9 for communicating the safety valve 21 to the outside is provided in the resin molding part 1, and the resin intrusion prevention part 9 for disposing the temperature protection element 6 is provided in the holder 4. The battery pack provided with the two resin intrusion prevention portions 9 is
The resin intrusion prevention portion 9 in which the temperature protection element 6 is arranged does not necessarily need to be communicated with the outside.

In the holder 4 shown in FIGS. 7 and 8, a resin intrusion prevention portion 9 is formed by a U-shaped peripheral wall 4A that contacts the electrode end surface of the battery 2 and a resin injection prevention wall 4B that closes the opening of the peripheral wall 4A. is doing. 7 and 8, the resin invasion prevention portion 9 has an opening at the right end, and discharges the gas or the like that passes through the safety valve 21 and is discharged to the outside. The resin intrusion prevention portion 9 has an opening on the surface facing the battery 2, but the opening is closed by the battery 2. In order to close the opening with the battery 2, the peripheral wall 4A is shaped so as to be in close contact with the end surface of the battery 2 without any gap, in other words, to have a shape along the end surface of the battery 2. The resin intrusion prevention portion 9 that closes the opening portion with the battery 2 allows the temperature protection element 6 disposed therein to approach the surface of the battery 2. Further, there is nothing that shuts off the temperature between the temperature protection element 6 and the battery 2. Therefore, the temperature protection element 6 can quickly detect an abnormal temperature rise of the battery 2 and cut off the current.

The temperature protection element 6 arranged in the resin intrusion prevention portion 9 of the holder 4 of FIGS. 7 and 8 is connected by soldering one lead 6B to the convex electrode 2B. Further, the other lead 6A of the temperature protection element 6 is drawn out from the opening at the right end of the resin intrusion prevention portion 9 in order to connect to the printed circuit board 5. The lead 6A drawn out of the resin intrusion prevention portion 9 is spot-welded and connected to the lead 5A connected to one end of the printed board 5. Furthermore, the printed circuit board 5 has the opposite end connected to the battery 2 via the electrode lead 8. The printed circuit board 5 has an electrode lead 8 spot-welded to a lead 5B connected to the other end.
Therefore, both ends of the printed circuit board 5 are connected to the battery 2 by the electrode lead 8 and the temperature protection element 6. Since the holder 4 is arranged between the printed circuit board 5 and the battery 2, the holder 4 is also arranged at a fixed position of the battery 2. Holder 4
Is sandwiched between the printed circuit board 5 and the battery 2 to dispose the printed circuit board 5 at a fixed position on the battery 2.

Further, the holder 4 of FIG. 8 is provided with a holding convex portion 23 at the opening edge facing the printed circuit board 5. The printed board 5 is provided with a fitting portion 24 by cutting out a position facing the holding convex portion 23. The printed board 5 and the holder 4 are connected at a predetermined position by fitting the holding convex portion 23 into the fitting portion 24. Further, in the printed circuit board 5 shown in FIGS. 7 and 8, the holder 4 and the printed circuit board 5 are mounted on the resin molding part 1.
A resin injection port 19 through which the molten resin is introduced is opened in order to bury and fix the resin. The resin injection port 19 shown in the drawing is opened at the end of the printed circuit board 5, and the molten resin is also injected into the back surface of the printed circuit board 5.

The battery pack holder 4 shown in FIG.
As shown in FIG.
The resin is blocked by B to form the resin intrusion prevention portion 9. The resin intrusion prevention portion 9 has an opening on the surface facing the battery 2, but the opening is closed by the battery 2. In order to close the opening with the battery 2, the peripheral wall 4A is formed into a shape that closely adheres to the side surface of the battery 2 without any gap, in other words, a shape that extends along the side surface of the battery 2. Since this resin invasion preventing portion 9 can also bring the temperature protection element 6 disposed therein close to the surface of the battery 2,
The temperature protection element 6 can promptly detect an abnormal temperature rise of the battery 2 to interrupt the current.

Further, as shown in FIG. 14, the holder 4 is provided with a convex portion 16 on the inner surface of the resin molding portion 1 for accommodating the temperature protection element 6. The temperature protection element 6 is provided in the resin intrusion prevention portion 9 by locally contacting the convex portion 16. With this structure, the temperature protection element 6 arranged in the resin intrusion prevention portion 9 can interrupt the current very quickly when the battery temperature rises. The temperature protection element 6 is a resin injection blocking wall 4B.
This is because the heat conduction to the resin invasion blocking portion 9 can be reduced by locally contacting the resin.

Further, in the holder 4 of FIG. 13, a connection window 17 for connecting the lead 6A of the temperature protection element 6 is opened in a part of the resin injection blocking wall 4B. This connection window 1
The printed circuit board 5 is in close contact with and closed. Connection window 1
The printed circuit board 5 that closes 7 is exposed inside the resin intrusion prevention portion 9. The exposed portion of the printed circuit board 5 is connected to one lead 6A of the temperature protection element 6 by soldering.
Further, in order to connect the other lead 6B of the temperature protection element 6 to the battery 2, a through hole 18 is also opened in the peripheral wall 4A. The through hole 18 has a slit shape that allows the lead 6B of the metal plate to be inserted without a gap, and the lead 6B is inserted into the through hole 18 to be closed. The lead 6 </ b> B that has passed through the through hole 18 and is drawn out of the resin intrusion prevention portion 9 is spot-welded and connected to the convex electrode 2 </ b> B of the battery 2 via the electrode lead 7.

Further, the holder 4 shown in FIGS. 12 and 13 is
A support wall 4C that supports the printed circuit board 5 is integrally formed at the same height as the peripheral wall 4A that constitutes the resin intrusion prevention portion 9. The support wall 4C is provided at a position that supports both sides of the printed circuit board 5. This support wall 4C is a printed circuit board 5
A resin injection port 19 is opened in the middle so as to be embedded and fixed in the resin molding portion 1. The resin injection port 19 is opened on both sides of the printed circuit board 5 so that the molten resin is filled with the printed circuit board 5.
Also infuse on the back side of. Further, the holder 4 in the drawing is provided with a lead guide 20 for holding the electrode lead 8 at the left end portion in FIG. The lead guide 20 holds the electrode lead 8 connected to the printed circuit board 5 and the battery 2, and holds the printed circuit board 5 in a fixed position of the holder 4 via the electrode lead 8. The printed circuit board 5 in the figure has the opposite end connected to the battery 2 via the temperature protection element 6. Both ends of the printed circuit board 5 are connected to the battery 2 by an electrode lead 8 and a temperature protection element 6. Since the holder 4 is disposed between the printed circuit board 5 and the battery 2, the holder 4
Is also arranged at a fixed position of the battery 2. The holder 4 is sandwiched between the printed circuit board 5 and the battery 2, and
Is arranged at a fixed position of the battery 2.

The resin molding portion 1 insert-molds the holder 4 and the battery 2 in the step of molding a synthetic resin. Since the temperature protection element 6 and the printed circuit board 5 are connected to the holder 4, the resin molding part 1 is provided with the holder 4 and the temperature protection element 6.
And the printed circuit board 5 and the battery 2 are integrally connected in a fixed position. In the above-mentioned battery pack, the entire battery 2 is made up of the resin molding part 1
Do not insert by embedding in. In the battery pack of FIGS. 2 to 6, the resin molding portion 1 is molded on the end surface of the battery 2.
This battery pack has a feature that the outer shape can be reduced. However, in the battery pack, the resin molding portion 1 can be molded on three sides of the battery 2 as shown in FIG. Furthermore, the battery pack may be inserted so that a part or almost all of the battery is embedded in the resin molding portion to form a battery pack having a solid and tough structure.

Polyamide or polyurethane is used as the synthetic resin for molding the resin molding portion 1. Since these synthetic resins have a low softening temperature and a low viscosity at the time of melting, they can be molded at a lower temperature and a lower pressure than general synthetic resins. Thus, the resin molding part 1 molded at low temperature and low pressure
Has the advantages that the time required for molding can be shortened and that adverse effects on the electronic parts and the like due to heat and injection pressure during resin molding can be reduced. Particularly, in a battery pack in which the temperature protection element 6 is arranged in the resin intrusion prevention portion 9, the influence of heat on the temperature protection element 6 due to the molten resin can be further reduced.

The above battery pack is manufactured as follows. (1) Printed circuit board 5 with temperature protection element 6 and electrode lead 8
Is connected to the battery 2, and the temperature protection element 6 and the printed circuit board 5 are connected.
The holder 4 is arranged at a fixed position of the battery 2. In this state, the holder 4 is located between the printed circuit board 5 and the battery 2, and the printed circuit board 5 and the battery 2 are connected to each other at an accurate relative position. Through the above steps, the printed circuit board 5, the holder 4, the temperature protection element 6, and the battery 2 are integrally connected to form the battery assembly 15.

(2) The battery assembly 15 is set in the molding chamber 11 of the mold 10. The battery pack shown in FIGS. 2 to 6 has a resin molding part 1 formed by a mold 10 having a structure shown in FIGS. 9 and 10.
To mold. Furthermore, the battery pack shown in FIG.
The resin molding part 1 is molded with the mold 10 shown in FIG.
After setting the battery assembly 15 in the molding chamber 11, the mold 10 is clamped. A mold chamber 11 for molding the resin molding part 1 is formed in the mold 10 that has been clamped. This molding room 1
1, the synthetic resin which is heated and melted is injected to mold the resin molding portion 1. The molten synthetic resin is the mold 10
It is injected from a liquid injection hole 12 opened in the. Injection hole 12
Are provided in communication with the molding chamber 11.

Further, the mold 10 shown in FIGS. 9 and 10 is
It has a positioning protrusion 13 for temporarily fixing the battery assembly 15 in place. The positioning protrusion 13 abuts on the surface of the holder 4 or the printed circuit board 5 to temporarily fix the battery assembly 15 at an accurate position. In FIG. 10, the positioning protrusions 13 located above and below press the surface of the holder 4 and temporarily fix it in place. These positioning projections 13 sandwich the holder 4 between the upper and lower portions and prevent the vertical displacement. Further, the holder 4 brings the four corners into contact with the inner surfaces of the corners of the mold 10 to prevent the lateral displacement. Furthermore, in the mold 10 of FIG. 9, the surface of the output terminal 3 of the printed board 5 is pressed by the positioning protrusion 13 and the bottom of the battery 2 is fixed to the mold 1.
It is brought into contact with the inner surface of the molding chamber 11 of 0 to prevent the battery assembly 15 from being displaced in the vertical direction. Furthermore, the positioning protrusion 13 that presses the surface of the output terminal 3 is formed by the molded resin molding portion 1.
To output the output terminal 3 to the outside.

Further, the mold 10 shown in FIG. 9 has an intrusion prevention convex portion 25 for preventing the molten synthetic resin from invading the resin intrusion prevention portion 9. The intrusion prevention convex portion 25 is provided so as to protrude to a position that closes the opening of the resin intrusion prevention portion 9 of the battery assembly 15 set in the molding chamber 11 in a state where the mold 10 is clamped. The resin intrusion prevention portion 9 in which the intrusion of the molten resin is prevented by the intrusion prevention convex portion 25 is provided in the safety valve 21.
Is surely communicated with the outside of the resin molding portion 1.

The mold 10 shown in FIGS. 14 and 15 has a central convex portion 14 and a positioning convex portion 13 for temporarily fixing the battery assembly 15 in place. The central convex portion 14 contacts the front side surface and the back side surface of the battery 2 to sandwich the battery 2 between the upper and lower central convex portions 14 and prevent the battery 2 from being displaced in the vertical direction. The positioning protrusion 13 presses the surface of the output terminal 3 provided on the printed circuit board 5. In this mold 10, the surface of the printed circuit board 5 is pressed by the positioning protrusions 13, and the side surface on the opposite side of the battery 2 is brought into contact with the inner surface of the molding chamber 11 so that the battery assembly 15
Prevents the positional displacement in the front-back direction. Furthermore, output terminal 3
The positioning protrusion 13 that presses the surface of the resin exposes the output terminal 3 from the molded resin molding portion 1 to the outside.

Further, the holder 4 shown in the figure has four corners.
D is brought into contact with the inner surface of the corner portion of the molding chamber 11 of the die 10 to prevent the holder 4 and the printed circuit board 5 from being displaced in the vertical and horizontal directions. In this manner, in the mold 10, the central convex portion 14 is brought into contact with the battery 2, the positioning convex portion 13 is brought into contact with the surface of the printed circuit board 5, and further, the corner 4D of the holder 4 is provided.
Is brought into contact with the inner surface of the mold 10 to temporarily fix the battery assembly 15 in place.

Further, the mold 10 shown in FIG. 15 has a molding convex portion 26 for forming the resin intrusion prevention portion 9 in the resin molding portion 1. The molding convex portion 26 is provided so as to project from the inner surface of the mold 10. The molding convex portion 26 is provided at a position that closes the opening of the safety valve 21 of the battery 2 set in the molding chamber 11 when the mold 10 is clamped. This molding convex portion 26
Is a safety valve 2 when the molten resin is injected into the molding chamber 11.
The opening of 1 is blocked by the resin, and the safety valve 21
A resin intrusion prevention portion 9 that communicates with the outside of the resin molding portion 1 is formed.

(4) The synthetic resin melted by heating is pressed into the molding chamber 11. As shown in FIGS. 7 and 14, the molten synthetic resin penetrates into the molding chamber 11 and does not penetrate into the resin invasion blocking portion 9. The resin molding part 1 molded in the molding chamber 11 is
The printed board 5, the holder 4, and the battery 2 are connected and fixed in an integrated structure. The synthetic resin is not injected into the resin intrusion prevention portion 9, and the safety valve 21 is communicated with the outside of the resin molding portion 1 by the resin intrusion prevention portion 9.

(5) Through the above steps, the battery assembly 15 is fixed in place by inserting the printed board 5, the holder 4 and the battery 2 into the resin molding portion 1. Then, the surface of the battery assembly 15 in which the resin molding portion 1 is molded is covered with a tube to complete the battery pack. Use heat-shrink tubing. After the battery assembly 15 in which the resin molding portion 1 is molded is put in the heat shrinkable tube, the heat shrinkable tube is heated and shrunk to be brought into close contact with the surface.

[0037]

The battery pack of the present invention and the manufacturing method thereof are as follows.
With a resin molding part that insert-molds batteries etc.,
The safety valve can be effectively prevented from being accidentally destroyed, and the safety valve can be protected by the resin molding part, and at the same time, the safety valve can be operated accurately to reliably prevent the internal pressure of the battery from rising.
According to the present invention, a resin intrusion preventing portion for preventing the intrusion of a synthetic resin is provided in a resin molding portion for insert molding of a battery or the like, and at the same time, the safety valve communicates with the outside of the resin molding portion by the resin intrusion prevention portion. This is because the path is formed and the gas discharged from the opened safety valve is discharged to the outside.

[Brief description of drawings]

FIG. 1 is a perspective view showing a manufacturing process of a conventional battery pack.

FIG. 2 is a plan view of a battery pack according to an embodiment of the present invention.

3 is a right side view of the battery pack shown in FIG.

4 is a front view of the battery pack shown in FIG.

5 is a cross-sectional view of the battery pack shown in FIG. 4 taken along the line BB.

6 is a sectional view of the battery pack shown in FIG. 2 taken along the line AA.

FIG. 7 is an enlarged cross-sectional view of a battery assembly in which the resin molding portion of the battery pack shown in FIG. 2 is not molded.

8 is an exploded perspective view of a battery assembly in which a resin molding portion of the battery pack shown in FIG. 2 is not molded.

9 is an exploded perspective view of a mold for molding a resin molding part of the battery pack shown in FIG.

10 is a cross-sectional view showing a state in which a resin molding portion is molded with the mold shown in FIG.

FIG. 11 is a plan view of a battery pack according to another embodiment of the present invention.

FIG. 12 is a perspective view of a battery assembly in which the resin molding portion of the battery pack shown in FIG. 11 is not molded.

13 is an exploded perspective view of the battery assembly shown in FIG.

14 is a cross-sectional view showing a state where the resin molding portion of the battery pack shown in FIG. 11 is molded with a mold.

15 is an exploded perspective view of a mold for molding a resin molding portion of the battery pack shown in FIG.

FIG. 16 is a sectional view showing another example of the safety valve.

[Explanation of symbols]

1 ... Resin molding part 2 ... Battery 2A ... Exterior can 2
B: convex electrode 2C: sealing plate 3 ... output terminal 4 ... holder 4A ... peripheral wall 4
B ... Resin injection blocking wall 4C ... Supporting wall 4D ... Corner 5 ... Printed circuit board 5A ... Lead 5
B ... Lead 6 ... Temperature protection element 6A ... Lead 6
B ... Lead 7 ... Electrode lead 8 ... Electrode lead 9 ... Resin invasion blocking portion 10 ... Mold 11 ... Molding chamber 12 ... Liquid injection hole 13 ... Positioning convex portion 14 ... Central convex portion 15 ... Battery assembly 16 ... Convex portion 17 ... Connection window 18 ... Through hole 19 ... Resin injection port 20 ... Lead guide 21 ... Safety valve 22 ... Breakage film 23 ... Holding projection 24 ... Fitting groove 25 ... Intrusion prevention projection 26 ... Molding projection 27 ... Elastic body 28 ... Valve Body 29 ... Valve seat 30 ... Discharge hole

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Mikitaka Tamai             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. F-term (reference) 5H040 AA33 AY04 AY08 DD10 DD26                       JJ05

Claims (10)

[Claims] 1. A battery (2) having a safety valve (21) which opens when the internal pressure of the battery (2) becomes higher than a set pressure, and this battery.
Resin molding part (1) formed by insert molding of (2)
In the battery pack including the resin molding part (1), the resin molding part (1) has a resin penetration blocking part (9) for blocking the penetration of the synthetic resin molding the resin molding part (1), and A battery pack in which a discharge passage is formed which connects the safety valve (21) to the outside of the resin molding portion (1) at 9). 2. A battery (2) having a safety valve (21) which opens when the internal pressure of the battery (2) becomes higher than a set pressure, and this battery.
Holder (4) fixed in place in (2) and holder (4)
Insert the battery (2) and insert the holder (4) into the battery (2)
A battery pack comprising a resin molding part (1) fixed to a holder, and a holder (4) having a resin intrusion prevention part (9) for preventing the intrusion of the synthetic resin molding the resin molding part (1). A battery pack having the resin intrusion prevention part (9) and a discharge path communicating the safety valve (21) with the outside. 3. A battery (2) is provided with a safety valve (21) on an electrode end surface having a convex electrode (2B), and a holder is provided on this electrode end surface.
The battery pack according to claim 2, wherein the resin molding portion (1) and the resin molding portion (1) are fixed. 4. The battery pack according to claim 2, wherein the resin molding part (1) insert-molds and fixes a holder (4) connecting the printed circuit board (5) in a fixed position. 5. The temperature protection element (6) is provided on the resin intrusion prevention part (9).
The battery pack according to claim 1, wherein the battery pack is provided. 6. The battery pack according to claim 5, wherein the temperature protection device (6) is a PTC or a thermal fuse. 7. The surface of the battery (2) is exposed to the resin intrusion prevention part (9), and the temperature protection element (6) arranged in the resin intrusion prevention part (9) approaches the battery (2). The battery pack according to claim 5, wherein 8. A mold (10) temporarily holds a battery (2) having a safety valve (21) that opens when the internal pressure of the battery (2) becomes higher than a preset pressure, A method for manufacturing a battery pack, in which a resin molding part (1) is molded on the end surface of the battery (2) provided with the safety valve (21) in the molding chamber (11) of (10), and the battery (2) is Resin molding part (1) in the molding chamber (11) temporarily fixed
At the time of molding the resin molding part (1), a resin intrusion prevention part (9) for preventing the intrusion of the molten synthetic resin for molding the resin molding part (1) is provided, and the safety valve (21) is provided at this resin intrusion prevention part (9). A manufacturing method of a battery pack, which forms a discharge path communicating with the outside. 9. A mold (10) temporarily holds a battery (2) having a safety valve (21) which opens when the internal pressure of the battery (2) becomes higher than a set pressure, and the mold (10) is fixed to the mold chamber (11). A method for manufacturing a battery pack, in which a resin molding part (1) is molded on an end surface of a battery (2) provided with a safety valve (21) in a molding chamber (11) of (10), In addition to the battery (2), a holder (4) having a resin intrusion prevention part (9) for preventing intrusion of a molten synthetic resin for molding the resin molding part (1) is provided in a molding chamber (11) for molding ) To the resin molding part (1)
(9) A method of manufacturing a battery pack, wherein a discharge path for communicating the safety valve (21) with the outside is formed. 10. A temperature protection element (6) is arranged on a resin intrusion prevention part (9) of a holder (4), and the holder (4) is temporarily fixed to a molding chamber (11) of a mold (10), The method for manufacturing a battery pack according to claim 9, wherein a synthetic resin in a molten state is injected into the molding chamber (11) of the mold (10) to mold the resin molding portion (1).