JP3906046B2 - Pack battery and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND 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 and a method for manufacturing the battery pack in which a battery is temporarily fixed in a molding chamber of a mold and connected to the battery to form a plastic resin molded portion.
[0002]
[Prior art]
A battery pack has been developed in which an outer case of the battery pack is used as a resin molded part, and the battery is insert-molded and fixed when the resin molded part is molded. In insert molding, a battery or a printed board is temporarily fixed in a molding room of a mold for molding a synthetic resin, and the battery or printed board temporarily fixed with a synthetic resin injected into the molding chamber is formed in close contact with the mold. To do. For this reason, a battery and a printed circuit board can be integrally fixed to the shape | molded resin molding part. This method has an advantage that the battery and the printed circuit board can be firmly fixed in place when the resin molding part is molded. It is possible to omit an assembling step of storing a battery or the like in a separately molded plastic case. That is, since molding and fixing can be performed simultaneously, there is a feature that mass production can be performed efficiently at low cost. A battery pack manufactured by this method is described in Japanese Patent Application Laid-Open No. 2000-315483. As shown in FIG. 1, the battery pack temporarily holds the printed circuit board 5 and the battery 2 in the molding chamber 11 of the mold 10 when the resin molding portion serving as the outer case is molded, and is melted in the molding chamber 11. It is manufactured by injecting synthetic resin. In this battery pack, a part of the printed circuit board 5 or the battery 2 is insert-molded and fixed to a resin molding portion. Unlike conventional battery packs, this battery pack does not require the battery and printed circuit board to be assembled in a separately molded case, and is a process of forming a resin molded part corresponding to the case. Can be fixed in place.
[0003]
[Problems to be solved by the invention]
However, it is difficult for the battery pack of this structure to operate the safety valve normally as compared with the conventional battery pack in which the battery is housed in a separately molded case. In a conventional battery pack in which a battery is housed in a separately molded case, gas discharged from the safety valve can be discharged into the case when the battery safety valve is opened. The gas discharged to the case passes through the gap of the case and is discharged to the outside. For this reason, the battery pack of this structure can operate the safety valve normally. However, it is difficult to quickly exhaust the gas discharged from the opened safety valve in a battery pack manufactured by insert molding a printed circuit board or the like in a resin molded portion. This is because the gap between the resin-molded portion and the battery is narrowed so that gas cannot pass smoothly. For this reason, when the internal pressure of the battery increases, the safety valve cannot be opened to promptly prevent the increase in the internal pressure of the battery. This problem can be solved by fixing the resin molding part to a part without the safety valve. However, since the battery pack with this structure exposes the opening of the safety valve to the outside, the safety valve may be accidentally destroyed from the outside. Since the safety valve is weakly manufactured so as to be easily destroyed by internal pressure, for example, when a needle-like foreign material comes into contact therewith, the safety valve is destroyed and cannot be used as a battery pack.
[0004]
The present invention has been 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 that can reliably prevent a rise in internal pressure of the battery by accurately operating the safety valve while protecting the safety valve.
[0005]
[Means for Solving the Problems]
[0006]
The battery pack according to claim 1 of the present invention includes 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 temperature protection element that is fixed at a fixed position of the battery 2. A holder 4 for fixing 6 in a fixed position; and a plastic resin molding portion 1 for fixing the holder 4 to the battery 2 by insert molding the holder 4 and the battery 2. The holder 4 includes a peripheral wall 4A and a resin injection blocking wall 4B that closes the opening of the peripheral wall 4A. The peripheral wall 4A and the resin injection wall 4B form a resin intrusion blocking portion 9. In the battery pack, the resin intrusion prevention unit 9 forms a discharge path that allows the safety valve 21 to communicate with the outside. In this battery pack, the safety valve 21 is provided on the electrode end surface of the battery 2 having the convex electrode 2B, and the holder 4 and the resin molded portion 1 can be fixed to the electrode end surface. Furthermore, this battery pack can be fixed by insert molding the holder 4 connecting the printed circuit board 5 at a fixed position to the resin molding portion 1.
[0008]
The battery pack manufacturing method of the present invention includes 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 temperature protection element 6 that is fixed at a fixed position of the battery (2). The holder 4 fixed at a fixed position is temporarily fixed to the molding chamber 11 of the mold 10, and the resin molding portion 1 is molded on the end surface of the battery 2 where the safety valve 21 is provided in the molding chamber 11 of the mold 10. The holder 4 has a peripheral wall 4A and a resin injection blocking wall 4B that closes the opening of the peripheral wall 4A. The peripheral wall 4A and the resin injection wall 4B form a resin intrusion blocking portion 9.
[0009]
Furthermore, manufacturing methods of the present invention, the molding chamber 11 for molding the resin molded portion 1, in addition to the battery 2, and temporarily held the e Ruda 4 by molding a resin molded portion 1, a resin intrusion prevention unit 9 A discharge path that communicates the safety valve 21 to the outside is formed.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. However, the examples shown 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. .
[0011]
Further, in this specification, in order to facilitate understanding of the scope of claims, the numbers corresponding to the members shown in the examples are referred to as “the scope of claims” and “the means for solving the problems”. It is added to the member shown by. However, the members shown in the claims are not limited to the members in the embodiments.
[0012]
In the battery pack shown in FIGS. 2 to 6 and FIG. 11, the resin molding portion 1 is molded and fixed to the peripheral portion of the battery 2. 2 to 6, the resin molding part 1 is fixed to the electrode end face provided with the convex electrode 2B of the battery 2, and the battery pack of FIG. 11 is resin-molded on three sides including the electrode end face. Part 1 is fixed. As shown in FIGS. 7 and 8 and FIGS. 12 to 14, the resin molding part 1 inserts and fixes the holder 4 and the temperature protection element 6. 7, 8, 12, and 13 show a battery pack in which the resin molded portion 1 is not molded in order to make the holder 4 built in the resin molded portion 1 easier to understand. 8 and 13 show perspective views with parts disassembled.
[0013]
The battery pack shown in these figures includes a battery 2, a temperature protection element 6 connected to the battery 2, a printed circuit board 5 on which a protection circuit is mounted, the printed circuit board 5 and the temperature protection element 6 in place. And a resin molding part 1 that connects the holder 4 to the battery 2.
[0014]
The battery 2 is a rechargeable secondary battery such as a lithium ion battery, a nickel-hydrogen battery, or a nickel-cadmium battery. The battery 2 in the figure is a thin prismatic battery, and has a shape in which both sides of the outer can 2A are curved surfaces and the corners of the four corners of the outer can 2A are chamfered. When a lithium ion battery is used for a thin prismatic battery, there is an advantage that the charge capacity with respect to the capacity of the whole pack battery can be increased. In this battery 2, a safety valve 21 is provided on a sealing plate 2C located on an electrode end face on which the convex electrode 2B is provided. The illustrated battery 2 is provided with a convex electrode 2B at the center of the sealing plate 2C and a safety valve 21 at one end. The battery can also incorporate a safety valve 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, and stops the increase in internal pressure of the outer can 2A. The safety valve 21 is a rupture film 22 that is airtightly adhered to an opening portion opened in the sealing plate 2C. The destruction film 22 is destroyed 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 destructive membrane, a safety valve can be used that has a structure in which a portion of the outer can is processed to be easily broken. Furthermore, as the safety valve built in the convex electrode, as shown in FIG. 16, a structure in which the elastic body 27 presses the valve body 28 against the valve seat 29 can be used. The safety valve 21 is opened when the valve body 28 is pushed by the internal pressure, and gas or the like is discharged from the discharge hole 30.
[0015]
The printed circuit board 5 is mounted with an electronic component that realizes a protection circuit for the battery 2. In the battery pack of this figure, the protection circuit is mounted on the printed circuit board 5, but the protection circuit can be arranged as a small IC in the resin molding portion. This battery pack can omit a printed circuit board. Further, the battery pack of FIGS. 4 and 11 has the output terminal 3 fixed to the printed circuit board 5.
[0016]
The battery pack includes a holder 4 for temporarily fixing the temperature protection element 6 and the printed circuit board 5 to an accurate position of the mold and insert-molding and fixing the temperature protection element 6 and the printed circuit board 5 at a fixed position of the resin molding portion 1. The holder 4 is molded from plastic separately from the resin molding part 1. This holder 4 is insert-molded and fixed to the resin molding part 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 synthetic resin in a molten state is injected into the molding chamber of the mold to mold the resin molding part 1. The holder 4 and the battery 2 temporarily secured in the molding chamber are partially embedded in the resin molding portion 1 and fixed.
[0017]
In the battery pack shown in the figure, the holder 4 is insert-molded into the resin molding portion 1 while the printed circuit board 5 and the temperature protection element 6 are held in place. In the battery pack, a resin intrusion prevention portion 9 that prevents intrusion of a synthetic resin that forms the resin molding portion 1 is provided in the holder 4 or the resin molding portion 1. The resin intrusion prevention unit 9 forms a discharge path that allows the safety valve 21 to communicate with the outside of the resin molding unit 1. This discharge path discharges the gas and electrolyte discharged from the opened safety valve 21 and the fragments of contents such as electrode plates and separators to the outside. The battery pack of FIGS. 7 and 8 is provided with a resin intrusion prevention portion 9 in the holder 4. The resin intrusion prevention unit 9 opens at one end (right end in the figure) and communicates the opening of the safety valve 21 to the outside. The resin intrusion prevention unit 9 is not necessarily provided in the holder 4. As shown in FIG. 11, a resin intrusion prevention unit 9 can be provided in the resin molding unit 1. This battery pack opens to the side (upper surface in the drawing) of the resin molding portion 1 and communicates the opening of the safety valve 21 to the outside.
[0018]
As shown in FIGS. 7 and 8, the resin intrusion prevention unit 9 can be provided with a temperature protection element 6. The temperature protection element 6 is an element that is connected in series with the battery 2 and cuts off current when the battery 2 becomes higher than a set temperature, and is a PTC or a temperature fuse. The temperature protection element 6 does not necessarily need to be disposed in the resin intrusion prevention unit 9 that communicates the opening of the safety valve 21 to the outside. As shown in FIG. 14, the battery pack of FIG. 11 is provided with two resin intrusion prevention portions 9, one resin intrusion prevention portion 9 forms a discharge path that communicates the safety valve 21 to the outside, and the other resin intrusion prevention portion 9. A temperature protection element 6 is disposed in the blocking portion 9. The resin intrusion prevention unit 9 that communicates the safety valve 21 to the outside is provided in the resin molding unit 1, and the resin intrusion prevention unit 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 does not necessarily need to communicate with the resin intrusion prevention portion 9 in which the temperature protection element 6 is disposed.
[0019]
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. . 7 and 8, the resin intrusion prevention unit 9 opens at the right end and discharges gas or the like that passes through the safety valve 21 and is discharged to the outside. The resin intrusion prevention unit 9 has an opening on the surface facing the battery 2, but the opening is closed with the battery 2. In order to close the opening with the battery 2, the peripheral wall 4 </ b> A is formed into a shape that closely contacts the end face of the battery 2 without a gap, in other words, a shape that follows the end face of the battery 2. The resin intrusion prevention unit 9 that closes the opening with the battery 2 can bring the temperature protection element 6 disposed here closer to the surface of the battery 2. Further, there is nothing that cuts off the temperature between the temperature protection element 6 and the battery 2. For this reason, the temperature protection element 6 can quickly detect an abnormal temperature rise of the battery 2 and interrupt the current.
[0020]
The temperature protection element 6 disposed in the resin intrusion prevention unit 9 of the holder 4 in FIGS. 7 and 8 is connected by soldering one lead 6B to the convex electrode 2B. Further, the other lead 6 </ b> A of the temperature protection element 6 is drawn out from the opening at the right end of the resin intrusion prevention unit 9 in order to connect to the printed circuit board 5. The lead 6 </ b> A drawn out of the resin intrusion prevention unit 9 is connected to the lead 5 </ b> A connected to one end of the printed circuit board 5 by spot welding. Further, the printed circuit board 5 has the opposite end connected to the battery 2 via the electrode lead 8. The printed circuit board 5 spot welds the electrode lead 8 to the lead 5B connected to the other end. Therefore, both ends of the printed board 5 are connected to the battery 2 by the electrode lead 8 and the temperature protection element 6. Since the holder 4 is disposed between the printed board 5 and the battery 2, the holder 4 is also disposed at a fixed position of the battery 2. The holder 4 is sandwiched between the printed circuit board 5 and the battery 2 and arranges the printed circuit board 5 at a fixed position of the battery 2.
[0021]
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 circuit board 5 is provided with an insertion portion 24 by notching a position facing the holding convex portion 23. The printed circuit board 5 and the holder 4 are connected at a predetermined position by inserting the holding convex portion 23 into the fitting portion 24. Further, the printed circuit board 5 shown in FIGS. 7 and 8 has a resin injection port 19 through which the molten resin enters to embed and fix the holder 4 and the printed circuit board 5 in the resin molding portion 1. The resin injection port 19 shown in the figure 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.
[0022]
In the battery pack holder 4 of FIG. 11, as shown in FIG. 13, the opening portion of the peripheral wall 4A is closed by the resin injection prevention wall 4B to form the resin intrusion prevention portion 9. The resin intrusion prevention unit 9 has an opening on the surface facing the battery 2, but the opening is closed with the battery 2. In order to close the opening with the battery 2, the peripheral wall 4 </ b> A is formed into a shape that closely contacts the side surface of the battery 2 without a gap, in other words, a shape along the side surface of the battery 2. The resin intrusion prevention unit 9 can also approach the surface of the battery 2 with the temperature protection element 6 disposed here, so that the temperature protection element 6 can quickly detect an abnormal temperature rise of the battery 2 and interrupt the current. .
[0023]
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 that houses the temperature protection element 6. The temperature protection element 6 is disposed in the resin intrusion prevention unit 9 in contact with the convex portion 16 locally. The temperature protection element 6 disposed in the resin intrusion prevention unit 9 with this structure can cut off the current very quickly when the battery temperature rises. This is because the temperature protection element 6 is locally in contact with the resin injection prevention wall 4B and heat conduction to the resin intrusion prevention part 9 can be reduced.
[0024]
Further, the holder 4 of FIG. 13 has a connection window 17 for connecting the lead 6A of the temperature protection element 6 in a part of the resin injection blocking wall 4B. The connection window 17 is closed by closely contacting the printed circuit board 5. The printed circuit board 5 that closes the connection window 17 is exposed inside the resin intrusion prevention unit 9. The exposed portion of the printed circuit board 5 is connected by soldering one lead 6A of the temperature protection element 6. Further, in order to connect the other lead 6 </ b> B of the temperature protection element 6 to the battery 2, a through hole 18 is also opened in the peripheral wall 4 </ b> A. The through-hole 18 has a slit shape through which the lead 6B of the metal plate can be inserted without a gap, and is closed by inserting the lead 6B. The lead 6 </ b> B drawn through the through-hole 18 to the outside of the resin intrusion prevention unit 9 is spot-welded to the convex electrode 2 </ b> B of the battery 2 via the electrode lead 7.
[0025]
Further, the holder 4 in FIGS. 12 and 13 is integrally formed with a support wall 4C for supporting the printed circuit board 5 at the same height as the peripheral wall 4A constituting the resin intrusion prevention unit 9. The support wall 4 </ b> C is provided at a position that supports both sides of the printed circuit board 5. The support wall 4 </ b> C has a resin inlet 19 in the middle in order to embed and fix the printed circuit board 5 in the resin molding portion 1. The resin injection ports 19 are opened on both sides of the printed circuit board 5 so that the molten resin is also injected into the back surface of the printed circuit board 5. Further, the holder 4 shown in the figure is provided with a lead guide 20 for holding the electrode lead 8 at the left end 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 at a fixed position of the holder 4 through the electrode lead 8. The printed circuit board 5 shown in the figure is connected to the battery 2 via the temperature protection element 6 at the opposite end. The printed circuit board 5 is connected to the battery 2 at both ends by an electrode lead 8 and a temperature protection element 6. Since the holder 4 is disposed between the printed board 5 and the battery 2, the holder 4 is also disposed at a fixed position of the battery 2. The holder 4 is sandwiched between the printed circuit board 5 and the battery 2, and the printed circuit board 5 is disposed at a fixed position of the battery 2.
[0026]
The resin molding part 1 insert-molds the holder 4 and the battery 2 in the process of molding the synthetic resin. Since the temperature protection element 6 and the printed board 5 are connected to the holder 4, the resin molding unit 1 integrally connects the holder 4, the temperature protection element 6, the printed board 5, and the battery 2 at a fixed position. In the above battery pack, the entire battery 2 is embedded in the resin molding portion 1 and is not inserted. The battery pack shown in FIGS. 2 to 6 has a molded resin portion 1 formed on the end face 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. Further, the battery pack may be a battery pack having a firm and strong structure by inserting a part or almost the whole battery so as to be embedded in the resin molding portion.
[0027]
As the synthetic resin for molding the resin molding portion 1, polyamide or polyurethane is used. Since these synthetic resins have a low softening temperature and a low viscosity when melted, they can be molded at a lower temperature and lower pressure than general synthetic resins. As described above, the resin molded portion 1 molded at a low temperature and a low pressure can shorten the time required for molding, and can reduce adverse effects on electronic components due to heat and injection pressure during resin molding. In particular, in the battery pack in which the temperature protection element 6 is disposed in the resin intrusion prevention unit 9, the influence of heat on the temperature protection element 6 due to the molten resin can be further reduced.
[0028]
The above battery pack is manufactured as follows.
(1) The printed circuit board 5 is connected to the battery 2 by the temperature protection element 6 and the electrode lead 8, and the temperature protection element 6, the printed circuit board 5, and the holder 4 are disposed at fixed positions of the battery 2. In this state, the holder 4 is 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 a battery assembly 15.
[0029]
(2) The battery assembly 15 is set in the molding chamber 11 of the mold 10. In the battery pack shown in FIGS. 2 to 6, the resin molding part 1 is molded by the mold 10 having the structure shown in FIGS. 9 and 10. Further, in the battery pack shown in FIG. 11, the resin molding part 1 is molded by the mold 10 shown in FIGS. After the battery assembly 15 is set in the molding chamber 11, the mold 10 is clamped. The mold 10 thus clamped is formed with a molding chamber 11 for molding the resin molding part 1. A synthetic resin heated and melted is injected into the molding chamber 11 to mold the resin molding portion 1. The melted synthetic resin is injected from a liquid injection hole 12 opened in the mold 10. The liquid injection hole 12 is provided in communication with the molding chamber 11.
[0030]
Furthermore, the mold 10 shown in FIGS. 9 and 10 has a positioning protrusion 13 that temporarily holds 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 positioned up and down press the surface of the holder 4 and temporarily hold it in place. These positioning protrusions 13 sandwich the holder 4 from above and below to prevent vertical displacement. Furthermore, the holder 4 abuts the four corners against the inner surface of the corner portion of the mold 10 to prevent lateral displacement. Furthermore, the mold 10 in FIG. 9 presses the surface of the output terminal 3 of the printed circuit board 5 with the positioning convex portion 13, and the bottom of the battery 2 is brought into contact with the inner surface of the molding chamber 11 of the mold 10. The vertical displacement of the battery assembly 15 is prevented. Further, the positioning convex portion 13 that presses the surface of the output terminal 3 causes the output terminal 3 to be exposed to the outside from the molded resin molded portion 1.
[0031]
Furthermore, the mold 10 shown in FIG. 9 has an intrusion prevention convex portion 25 that prevents the molten synthetic resin from entering the resin intrusion prevention portion 9. The intrusion prevention convex portion 25 is provided so as to protrude at a position to close 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 unit 9 in which the intrusion of the molten resin is prevented by the intrusion prevention convex part 25 reliably communicates the safety valve 21 to the outside of the resin molding part 1.
[0032]
The mold 10 shown in FIGS. 14 and 15 includes a central convex portion 14 and a positioning convex portion 13 that temporarily hold the battery assembly 15 in place. The central convex portion 14 is in contact with the front side surface and the back side surface of the battery 2, and the battery 2 is sandwiched between the upper and lower central convex portions 14 to prevent the vertical displacement of the battery 2. 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 projection 13 and the opposite side surface of the battery 2 is brought into contact with the inner surface of the molding chamber 11 so that the battery assembly 15 is positioned in the front-rear direction. Prevent deviation. Further, the positioning convex portion 13 that presses the surface of the output terminal 3 causes the output terminal 3 to be exposed to the outside from the molded resin molded portion 1.
[0033]
Furthermore, the holder 4 shown in the figure makes the four corners 4D abut against the inner surface of the corner portion of the molding chamber 11 of the mold 10 to prevent the holder 4 and the printed board 5 from being displaced in the vertical and horizontal directions. As described above, the mold 10 has the central convex portion 14 in contact with the battery 2, the positioning convex portion 13 in contact with the surface of the printed circuit board 5, and the corner corner 4 </ b> D of the holder 4 is connected to the mold 10. The battery assembly 15 is temporarily fixed in place by contacting the inner surface.
[0034]
Further, the mold 10 shown in FIG. 15 has a molding convex portion 26 that forms the resin intrusion prevention portion 9 in the resin molding portion 1. The molding convex portion 26 is provided so as to protrude from the inner surface of the mold 10. The molding convex portion 26 is provided at a position where the opening of the safety valve 21 of the battery 2 set in the molding chamber 11 is closed while the mold 10 is clamped. The molding convex portion 26 prevents the opening of the safety valve 21 from being blocked by the resin when the molten resin is injected into the molding chamber 11, and prevents resin intrusion that allows the safety valve 21 to communicate with the outside of the resin molding portion 1. Part 9 is formed.
[0035]
(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 enters the molding chamber 11 and does not enter the resin intrusion prevention unit 9. The resin molding part 1 molded in the molding chamber 11 connects the printed circuit board 5, the holder 4 and the battery 2 in an integrated structure and fixes them. Synthetic resin is not injected into the resin intrusion prevention unit 9, and the safety valve 21 communicates with the outside of the resin molding unit 1 by the resin intrusion prevention unit 9.
[0036]
(5) Through the above steps, the battery assembly 15 is fixed in place by inserting the printed circuit board 5, the holder 4 and the battery 2 into the resin molding portion 1. Thereafter, the battery assembly 15 formed with the resin molded portion 1 is covered with a tube to obtain a completed battery pack. Use a heat-shrinkable tube. The heat-shrinkable tube is brought into close contact with the surface by heating and shrinking after the battery assembly 15 with the molded resin part 1 is formed.
[0037]
【The invention's effect】
The battery pack of the present invention and the manufacturing method thereof effectively prevent the safety valve from being accidentally destroyed by the resin molding part in which the battery or the like is insert-molded, and protect the safety valve by the resin molding part. It has the feature that the internal pressure of the battery can be prevented reliably by operating the safety valve accurately. The present invention provides a resin intrusion prevention portion for preventing the invasion of a synthetic resin in a resin molding portion in which a battery or the like is insert-molded, and a discharge that communicates a safety valve to the outside of the resin molding portion at the resin intrusion prevention portion. This is because a path is formed to discharge gas or the like discharged from the opened safety valve to the outside.
[Brief description of the drawings]
1 is a perspective view showing a conventional battery pack manufacturing process. FIG. 2 is a plan view of a battery pack according to an embodiment of the present invention. FIG. 3 is a right side view of the battery pack shown in FIG. 2 is a front view of the battery pack shown in FIG. 2. FIG. 5 is a cross-sectional view of the battery pack shown in FIG. 4 taken along line BB. FIG. 6 is a cross-sectional view of the battery pack shown in FIG. Fig. 8 is an enlarged cross-sectional view of a battery assembly in which the resin molded portion of the battery pack shown is not molded. Fig. 8 is an exploded perspective view of the battery assembly in which the resin molded portion of the battery pack shown in Fig. 2 is not molded. FIG. 10 is an exploded perspective view of a mold for molding a resin molding part of the battery pack shown in FIG. 10. FIG. 11 is a cross-sectional view showing a state in which the resin molding part is molded with the mold shown in FIG. Fig. 12 is a plan view of such a battery pack. Fig. 12 is a perspective view of a battery assembly in which the resin molding part of the battery pack shown in Fig. 11 is not formed. 13 is an exploded perspective view of the battery assembly shown in FIG. 12. 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. FIG. 16 is an exploded perspective view of a mold for molding a resin molding part. FIG. 16 is a sectional view showing another example of a safety valve.
DESCRIPTION OF SYMBOLS 1 ... Resin molding part 2 ... Battery 2A ... Exterior can 2B ... Convex part electrode 2C ... Sealing board 3 ... Output terminal 4 ... Holder 4A ... Peripheral wall 4B ... Resin injection | pouring prevention wall 4C ... Support wall 4D ... Corner corner 5 ... Printed circuit board 5A ... Lead 5B ... Lead 6 ... Temperature protection element 6A ... Lead 6B ... Lead 7 ... Electrode lead 8 ... Electrode lead 9 ... Resin intrusion prevention part 10 ... Mold 11 ... Molding chamber 12 ... Injection hole 13 ... Positioning convex part 14 ... Central convex part 15 ... Battery assembly 16 ... Convex part 17 ... Connection window 18 ... Through hole 19 ... Resin injection port 20 ... Lead guide 21 ... Safety valve 22 ... Destruction film 23 ... Holding convex part 24 ... Insertion groove 25 ... Intrusion prevention convex part Part 26 ... Molding convex part 27 ... Elastic body 28 ... Valve body 29 ... Valve seat 30 ... Discharge hole

Claims (4)

When the internal pressure of the battery (2) is higher than the set pressure and battery having a safety valve (21) to be opened (2), place a temperature protection device (6) is fixed in place of the battery (2) A battery pack including a holder (4) that is fixed to a battery, and a resin molded part (1) that insert-molds the holder (4) and the battery (2) to fix the holder (4) to the battery (2). And
The holder (4) has a peripheral wall (4A) and a resin injection blocking wall (4B) that closes the opening of the peripheral wall (4A), and the peripheral wall (4A) and the resin injection wall (4B) A battery pack in which a resin intrusion prevention portion (9) is formed, and a discharge path for communicating the safety valve (21) with the resin intrusion prevention portion (9) is formed.   The battery (2) is provided with a safety valve (21) on an electrode end face having a convex electrode (2B), and a holder (4) and a resin molding part (1) are fixed to the electrode end face. Battery pack.   The battery pack according to claim 1, wherein the resin molding part (1) inserts and fixes the holder (4) connecting the printed circuit board (5) in a fixed position. When the internal pressure of the battery (2) is higher than the set pressure and battery having a safety valve (21) to be opened (2), place a temperature protection device (6) is fixed in place of the battery (2) The holder (4) fixed to the mold (10) is temporarily secured in the molding chamber (11) of the mold (10), and the safety valve (21) of the battery (2) is provided in the molding chamber (11) of the mold (10). A battery pack manufacturing method for forming a resin molded part (1) on an end surface of the battery pack,
The holder (4) has a peripheral wall (4A) and a resin injection blocking wall (4B) that closes the opening of the peripheral wall (4A), and the peripheral wall (4A) and the resin injection wall (4B) Form a resin intrusion prevention part (9),
In the molding chamber (11) for molding the resin molding part (1), in addition to the battery (2), the holder (4) is temporarily fixed to mold the resin molding part (1), and the resin intrusion prevention part (9) A battery pack manufacturing method for forming a discharge path for communicating the safety valve (21) with the outside.

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