JP2002117819A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent irregular noise generation when a pulsed current flows through a load. SOLUTION: A battery case 10 is constituted of a 2-division type composed of the body part 11 and a cap part 12, and the battery body 20 is housed inside. Reeds 25, 27 drawn out of the battery body 20 are connected with an external connection terminal 31, and silicon resin 35 has been made to flow and to solidify in order to fill up the reeds 25, 27, and PTC 26 has been also fixed in combination. The reeds 25, 27 are surely fixed by this, and that these are vibrated is eliminated even if an electromagnetic force acts between reeds 25, 27.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery pack having a battery body housed in a battery case.

[0002]

2. Description of the Related Art For example, in a battery pack of a portable telephone, a battery main body and a protection circuit are housed in a thin box-shaped two-part battery case, and leads led out from the battery main body are connected to a circuit of the protection circuit. In general, a connection is made to an external connection terminal on a substrate, and the external connection terminal faces the outside through an opening formed in the battery case.

[0003]

By the way, there are various communication systems in a portable telephone system, and in recent years, a transition from an analog system to a digital system is progressing. However, there are various types of digital systems, and a problem has been pointed out that abnormal noise may be generated from a battery pack during communication in a mobile phone employing a digital communication system called the GSM system of the European standard. Was.

According to the present inventors' investigation into the cause, in the digital system, a load current of a battery becomes a pulse current in order to transmit a signal in a burst manner.
In the method, the frequency of the pulse current is in the audible band,
In addition, it was found that the current value was large.
A pulse current having an audible frequency flows through the leads, and the leads vibrate due to the electromagnetic action between the leads, so that the leads are heard as abnormal noise.

The present invention has been completed in view of the above circumstances, and provides a battery pack capable of reliably preventing generation of abnormal noise even when a pulse current flows through a load. The purpose is to:

[0006]

In order to achieve the above object, according to the present invention, a battery body is housed in a battery case and a lead derived from the battery body is connected to an external connection terminal. The battery pack is characterized in that the leads are fixed by a resin filling the leads.

According to a second aspect of the present invention, a temperature-sensitive current-limiting element for interrupting a current according to the temperature is provided at an intermediate portion of the lead, and the temperature-sensitive current-limiting element is overlapped on the surface of the battery body by the resin. It is characterized by being fixed. Claim 3
In the invention, the battery case is formed into a two-part type with a main body and a lid, and the resin is poured in a state where the lid is opened.
The present invention is characterized in that the lid is closed while being in contact with the poured resin.

[0008]

According to the first aspect of the present invention, the resin does not move because the resin is solidified so as to fill the lead extending from the battery body. Therefore, even if a pulse current flows at a frequency in the audible frequency band as a load current and an electromagnetic force acts between the leads, generation of abnormal noise due to vibration of the leads can be reliably prevented. In addition, as the resin, a solvent type, a non-solvent type,
Various types such as a one-pack type, a two-pack type, and a hot-melt type can be widely used, but a non-solvent type silicone resin is most suitable.

<Invention of claim 2> In the invention of claim 2,
The temperature-sensitive current-limiting element is fixed with a resin together with the lead, and the temperature-sensitive current-limiting element is held in contact with the surface of the battery body. For this reason, the vibration of the lead can be prevented, and the temperature-sensitive current-limiting element is fixed to the battery main body, so that the positional relationship is stabilized and the heat conductivity is improved, so that the thermal response is improved. The temperature-sensitive current limiting element includes a temperature fuse and a PTC element, and may have any structure as long as it interrupts (limits) the current according to the temperature.

<Invention of claim 3>

According to the third aspect of the present invention, since the lid is closed by contacting the resin, the lid can be fixed using the resin for fixing the lead, and the user is inadvertent. Since the lid can be prevented from being opened, safety is enhanced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a battery pack for a portable telephone will be described below with reference to the drawings. The overall structure of this battery pack is shown in FIG. 1, in which a battery body 20 is housed in a thin box-shaped battery case 10. The battery case 10 is divided into two parts in the thickness direction. It comprises a part 11 and a lid part 12. In the battery case 10, a protection circuit 30 connected to the battery body 20 via the lead 21 is also housed, and an external connection terminal 31 provided in the protection circuit 30 is connected to the battery case 10 as shown in FIG. The window 13 formed in the lid 12 is exposed to the outside.

Note that, as shown in FIG.
The main body 11 has a plastic frame 14 having an opening 14A and a metal sheet 1 for closing the opening 14A.
4B and a fixing sheet 14C for fixing the metal sheet 14B to the frame 14. On the other hand, the lid 12
Also, a plastic frame 15 having an opening 15A
And a metal sheet 16 with an adhesive that closes the opening 15B. Further, the battery body 20 is formed by sealing a power generating element constituting, for example, a lithium ion type secondary battery with a resin film laminated with an aluminum foil into a flat shape, as shown in FIG. Sealing portions 21 and 22 formed by thermal fusion are provided at both ends. A pair of battery leads 23 extends from one sealing portion 21.

Now, the connection configuration between the battery body 20 and the protection circuit 30 will be described together with the operation procedure. First, an insulating tape 24 is attached to the sealing portion 21 of the battery body 20, and the lead 25 is welded to one of the battery leads 23.
The lead 25 is connected to a PTC 26 which is a temperature-sensitive current limiting element, and this is connected to the PTC 26 as shown by an arrow in FIG.
At the lead 26A. Then, as shown in FIG. 5, the battery body 20 is turned over, one connection terminal 32 of the protection circuit 30 is connected to the lead terminal 26A of the PTC 26, and the other connection terminal 32 is connected to the other battery of the battery body 20 via the lead 27. Connect to terminal 23. In this state, as shown in FIG. 6, the surface of the protection circuit 30 opposite to the external connection terminal 31 is in contact with the battery main body 20. .

Then, the battery body 20 is turned over again, and FIG.
As shown in FIG. 3, a non-solvent type silicone resin 35 is applied on the insulating tape 24, and the protection circuit 30 is rotated about 180 degrees in the direction shown by the arrow in FIG. Let it. Then, as shown in FIG. 8, the PTC 26 is
0 on the sealing portion 21. Therefore, this is accommodated in the main body 11 of the battery case 10, and the silicon resin 35 is again flown on the leads 25 and 27 together with the PTC 26 so that the leads 25 and 27 are embedded with the resin. When the main body 11 of the battery case 10 is closed by the lid 12, the back surface of the lid 12
The silicon resin 35 is solidified in a state in which the silicon resin 35 is in contact with the silicon resin 35.

According to the above-described embodiment, the leads 25 and 27 are completely fixed in the battery case 10 by the solidified silicon resin 35. For this reason, even if a large pulse current flows as the load current of the battery and this is the frequency in the audible band, the lead 25,
27, the leads 25, 27
It is possible to reliably prevent vibrations from generating abnormal noise. Moreover, in the present embodiment, the PTC 26 is made of the silicon resin 35 together with the leads 25 and 27, and
PTC2 is fixed so as to overlap the surface of PTC2.
6 and the thermal relationship between the battery body 20 and the thermal relationship is stabilized, so that even if a short circuit accident or overcharging occurs and the battery body 20 is overheated, the PTC 26 is reliably operated. The current can be interrupted early. Furthermore, in this embodiment, since the lid 12 of the battery case 10 is closed in contact with the silicone resin 35,
The lid 12 cannot be opened, so that it is possible to reliably prevent the user from inadvertently opening the lid 12, and the safety is high.

<Other Embodiments>

The present invention is not limited to the embodiment described above with reference to the drawings. For example, the following embodiment is also included in the technical scope of the present invention, and further departs from the gist in addition to the following. Various changes can be made without departing from the scope of the present invention.

(1) In the above embodiment, a non-solvent type silicone resin is used as the resin for fixing the lead. However, the present invention is not limited to this. Any type of resin can be used as long as it has a property of being hard enough to fix the lead to the lead. In addition, even if it has some elasticity in a solidified state, it is sufficient that vibration of the lead can be suppressed. In addition, among various resins, one-part adhesives are easy to handle,
The solventless type is preferable from the viewpoint of environmental protection, and the room temperature curing type is preferable because damage to the protection circuit 30 can be suppressed.

(2) In the above embodiment, the PTC 26 is fixed together with the silicon resin 35. However, even if only the leads 25 and 27 are fixed, generation of abnormal noise from the leads can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a battery pack showing one embodiment of the present invention.

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is a perspective view showing an assembling process and showing a state before attaching an insulating tape;

FIG. 4 is a perspective view showing a state after the lead 25 is attached.

FIG. 5 is a perspective view showing a state before the protection circuit 30 is attached.

FIG. 6 is a perspective view showing a state after the protection circuit 30 is mounted.

FIG. 7 is a perspective view showing a state after application of a resin.

FIG. 8 is a perspective view showing a state in which the lead 25 is embedded in a resin.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Battery case 11 ... Main body part 12 ... Lid part 20 ... Battery main body 25,27 ... Lead 26 ... PTC (temperature-sensitive current limiting element) 30 ... Protective circuit 35 ... Silicon resin

Claims (3)

[Claims] 1. A battery pack comprising a battery body housed in a battery case and connecting a lead derived from the battery body to an external connection terminal, wherein the lead is fixed by a resin filling the lead. Battery pack characterized by the following: 2. A temperature-sensitive current-limiting element for interrupting a current in accordance with a temperature is provided at an intermediate portion of the lead, and the temperature-sensitive current-limiting element is fixed by being superposed on the surface of the battery body by the resin. The battery pack according to claim 1, wherein 3. The battery case is configured as a two-piece type having a main body portion and a lid portion. The resin is poured in a state where the lid portion is opened, and then the lid portion is brought into contact with the poured resin. The battery pack according to claim 1, wherein the lid is closed in a state where the battery pack is closed.