JP2008159351A - Battery device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a safe and secure battery device. <P>SOLUTION: This battery device is equipped with an electric circuit 12 and an external electrode 13 which are connected to a battery body 11, and a temperature fuse 14 mounted to the battery body 11 though the electric circuit 12 and the external electrode 13. The temperature fuse 14 has a first insulating film to which a first metal terminal 15 and a second metal terminal 16 are mounted, and a soluble alloy positioned in the upper part of the first insulating film and connected between one end part of the first metal terminal 15 and one end part of the metal terminal 16, the other end part of the first metal terminal 15 is connected to the electric circuit 13, the other end part of the second metal terminal 16 is connected to the external electrode 13, and the thermal conductivity of the first metal terminal 15 is made smaller than the thermal conductivity of the second metal terminal 16. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a battery device using a thermal fuse used to prevent damage to equipment due to excessive temperature rise.

  In recent years, as portable information devices such as mobile phones and mobile PCs have become smaller and more functional, battery devices used for the power supply have also been reduced in size and energy density. For this reason, in addition to miniaturization, thermal fuses used in these battery devices are required to have a highly safe fuse design that matches the design of the battery device.

  As shown in FIG. 7, this type of conventional battery device includes a battery body 1, an electric circuit 2 and an external electrode 3 connected to the battery body 1, and a thermal fuse 4 attached to the battery body 1. It has. Further, a first metal terminal 5 and a second metal terminal 6 are provided at both ends of the thermal fuse 4, and the first metal terminal 5 is connected to the electric circuit 2 and the second metal terminal 6. Is connected to the external electrode 3.

As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.
JP 2004-831426 A

  However, in the above-described conventional battery device, the heat of the electric circuit 2 in the normal state is transmitted to the temperature fuse 4 through the first metal terminal 5, and the temperature fuse 4 is operated and opened. In this case, the temperature fuse 4 does not operate even if the battery main body 1 abnormally generates heat thereafter, and as a result, the safety of the battery device cannot be ensured.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a highly safe battery device.

  In order to achieve the above object, the present invention has the following configuration.

  According to a first aspect of the present invention, there is provided a battery main body, an electric circuit and an external electrode connected to the battery main body, and a thermal fuse attached to the battery main body through the electric circuit and the external electrode. The thermal fuse includes a first insulating film to which a first metal terminal and a second metal terminal are attached, and one end portion of the first metal terminal positioned above the first insulating film. The first alloy so as to form a space between a fusible alloy connected between one end of the second metal terminal and the fusible alloy and the first insulating film. A second insulating film attached to the insulating film, connecting the other end of the first metal terminal and the electric circuit, and the other end of the second metal terminal and the external An electrode, and further, the first metal terminal The conductivity is smaller than the thermal conductivity of the second metal terminal. According to this configuration, the thermal conductivity of the first metal terminal is smaller than the thermal conductivity of the second metal terminal. In normal times, the heat of the electric circuit is not easily transmitted to the thermal fuse, and as a result, the thermal fuse will not operate in normal times. The effect that it can be obtained is obtained.

  The invention according to claim 2 of the present invention is particularly the one in which the first metal terminal is provided with a notch, and according to this configuration, the effect of being able to easily reduce the thermal conductivity of the first metal terminal. Is obtained.

  According to the third aspect of the present invention, in particular, the cross-sectional area of the first metal terminal is made smaller than the cross-sectional area of the second metal terminal. According to this configuration, the heat of the first metal terminal is The effect that the conductivity can be easily reduced is obtained.

  In the invention according to claim 4 of the present invention, in particular, a heat insulating layer is formed on the first metal terminal. According to this configuration, the heat of the electric circuit transmitted through the first metal terminal is inhibited by the heat insulating layer. As a result, it is possible to obtain an effect that the heat of the electric circuit in normal times is hardly transmitted to the thermal fuse.

  In the invention according to claim 5 of the present invention, in particular, the diameter of the soluble alloy located on the first metal terminal side is made larger than the diameter of the soluble alloy located on the second metal terminal side. According to this configuration, even if the heat of the electric circuit reaches the thermal fuse through the first metal terminal, the fusible alloy is difficult to melt because the diameter of the fusible alloy is large, and thus the electric alloy is normally discharged. It is possible to obtain an effect that the thermal fuse can be prevented from operating due to the heat of the circuit.

  As described above, in the battery device of the present invention, the thermal conductivity of the first metal terminal in the thermal fuse is made smaller than the thermal conductivity of the second metal terminal. As a result, it is difficult for the thermal fuse to be transmitted to the thermal fuse, and as a result, the thermal fuse does not operate in normal times, so that the thermal fuse can be reliably operated during abnormal heating of the battery body. .

  Hereinafter, a battery device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view of a battery device according to an embodiment of the present invention.

  As shown in FIG. 1, the battery device according to an embodiment of the present invention includes a battery main body 11, an electric circuit 12 and an external electrode 13 connected to the battery main body 11, and the electric circuit 12 and the external electrode 13. And a thermal fuse 14 attached to the battery main body 11. The battery body 11 includes a power generation element and a battery can containing the power generation element, and the electric circuit 12 includes a protection circuit that controls charging and discharging of the battery body 11. It is electrically connected to the battery body 11.

  FIG. 2 is a top view of a thermal fuse used in the battery device according to the embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along line AA in FIG.

  As shown in FIGS. 2 and 3, the thermal fuse 14 used in the battery device according to the embodiment of the present invention is a first insulating film to which a first metal terminal 15 and a second metal terminal 16 are attached. 17, a fusible alloy 18 located above the first insulating film 17 and connected between one end of the first metal terminal 15 and one end of the second metal terminal 16, A second insulating film 19 located above the fusible alloy 18 and attached to the first insulating film 17 so as to form a space with the first insulating film 17; Yes. The other end of the first metal terminal 15 is connected to the electric circuit 12, and the other end of the second metal terminal 16 is connected to the external electrode 13. Further, the first metal terminal 15 is provided with a notch 20.

  In the above configuration, the first metal terminal 15 and the second metal terminal 16 are made of a flat metal having good conductivity such as iron, copper, nickel, and the surface thereof is solder plated, tin plated, Copper plating etc. are given. The first metal terminal 15 and the second metal terminal 16 may not be flat but may be linear. One end of each of the first metal terminal 15 and the second metal terminal 16 is provided on the upper surface of the first insulating film 17. The first metal terminal 15 is provided with a notch 20 so that the thermal conductivity of the first metal terminal 15 is smaller than the thermal conductivity of the second metal terminal 16.

  The first insulating film 17 and the second insulating film 19 are formed in a flat plate shape from a resin such as polyethylene terephthalate (hereinafter referred to as PET), and the first insulating film 17 and the second insulating film 19 A space is formed between the two films 17 and 19 by bonding the film 19 by ultrasonic welding or the like. In the space, the fusible alloy 18 is electrically connected to the first metal terminal 15 and the second metal terminal 16, respectively. And is composed of an alloy of two or more metals such as tin, bismuth, and indium. Further, a flux 21 mainly composed of rosin is applied around the soluble alloy 18. The battery device described above is sealed in an insulating case or the like and used as a battery pack such as a mobile phone.

  The temperature fuse used in the battery device according to the embodiment of the present invention is a temperature fuse in which the first metal terminal 15 and the second metal terminal 16 are positioned on the upper surface of the first insulating film 17. However, the first insulating film 17 having through holes at both ends thereof is positioned on the upper surfaces of the first metal terminal 15 and the second metal terminal 16 having protrusions whose front ends protrude upward. In addition, the present invention can also be applied to a thermal fuse in which the first metal terminal 15 and the second metal terminal 16 are connected to both end portions of the fusible alloy 18 by passing the protrusion through the through hole. It is.

  Next, a method for manufacturing a battery device according to an embodiment of the present invention will be described with reference to FIGS.

  First, as shown in FIG. 1, a battery body 11 including an electric circuit 12 and an external electrode 13 is prepared.

  Next, as shown in FIG. 2 and FIG. 3, after forming the notch 20 in the first metal terminal 15 by processing such as punching, the first metal terminal is formed at both ends of the upper surface of the first insulating film 17. 15 and the second metal terminal 16 are arranged.

  Next, a soluble alloy 18 is bridged between one end of the first metal terminal 15 and one end of the second metal terminal 16. Then, the flux 21 is applied around the fusible alloy 18.

  Next, a second insulating film 19 is formed on the upper surface of the first insulating film 17 so as to cover the fusible alloy 18. In addition, the adhesion method of the 1st insulating film 17 and the 2nd insulating film 19 makes a predetermined jig contact | abut to the lower surface of the 1st insulating film 17 in the adhesion part, and the upper surface of the 2nd insulating film 19, respectively. It is performed by ultrasonic welding or thermocompression bonding.

  Finally, the other end of the first metal terminal 15 is connected to the electric circuit 12, and the other end of the second metal terminal 16 is connected to the external electrode 13, and the thermal fuse 14 is attached to the battery body 11. .

  As described above, in the battery device according to the embodiment of the present invention, the first metal terminal 15 has the notch 20 so that the first metal terminal 15 has the thermal conductivity of the second metal terminal 16. Therefore, the heat of the electric circuit 12 is difficult to be transmitted to the thermal fuse 14 in normal times. As a result, since the temperature fuse 14 does not operate normally, the temperature fuse 14 operates only with abnormal heat generation of the battery main body 11, thereby providing a highly safe battery device. An effect is obtained.

  Further, in order to make the thermal conductivity of the first metal terminal 15 smaller than the thermal conductivity of the second metal terminal 16, a notch 20 is provided in the first metal terminal 15, and this notch 20 is punched or the like. It can be easily formed by simple processing.

  As a method for making the thermal conductivity of the first metal terminal 15 smaller than the thermal conductivity of the second metal terminal 16, as shown in FIG. It is made thinner than the thickness of the metal terminal 16. Furthermore, the cross-sectional area of the first metal terminal 15 may be made smaller than the cross-sectional area of the second metal terminal 16, such as making the width of the first metal terminal 15 narrower than the width of the second metal terminal 16.

  Further, as shown in FIG. 5, a heat insulating layer 22 may be formed on the first metal terminal 15, and in this case, the heat of the electric circuit 12 in a normal state is hardly transmitted to the thermal fuse 14.

  Furthermore, as shown in FIG. 6, the diameter of the soluble alloy 18 located on the first metal terminal 15 side may be larger than the diameter of the soluble alloy 18 located on the second metal terminal 16 side, In this case, even if the heat of the electric circuit 12 is transmitted through the first metal terminal 15 and reaches the temperature fuse 14, the soluble alloy 18 on the first metal terminal 15 side has a large diameter. Therefore, the thermal fuse 14 is not operated by the heat of the electric circuit 12 in normal times.

  In FIG. 6, the second insulating film 19 and the flux 21 are omitted for ease of explanation.

  The battery device according to the present invention can increase safety, and is particularly useful in a battery device using a thermal fuse used to prevent damage to equipment due to excessive temperature rise. .

The perspective view of the battery apparatus in one embodiment of this invention Top view of thermal fuse used in the battery device AA line sectional view of FIG. Sectional drawing of the other example of the thermal fuse used for the battery apparatus Sectional drawing of the other example of the thermal fuse used for the battery apparatus Top view of the main part of another example of thermal fuse used in the battery device A perspective view of a conventional battery device

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Battery main body 12 Electric circuit 13 External electrode 14 Thermal fuse 15 1st metal terminal 16 2nd metal terminal 17 1st insulation film 18 Soluble alloy 19 2nd insulation film 20 Notch 22 Heat insulation layer

Claims (5)

A battery main body, an electric circuit and an external electrode connected to the battery main body, and a temperature fuse attached to the battery main body through the electric circuit and the external electrode, the temperature fuse being a first metal terminal And a first insulating film to which a second metal terminal is attached, and between the one end of the first metal terminal and the one end of the second metal terminal located above the first insulating film. A second insulating film which is attached to the first insulating film so as to form a space between the connected fusible alloy and the fusible alloy and between the first insulating film and the first insulating film. And connecting the other end of the first metal terminal and the electric circuit, connecting the other end of the second metal terminal and the external electrode, and further connecting the first metal The thermal conductivity of the terminal is the heat of the second metal terminal. Smaller than Shiruberitsu the cell apparatus. The battery device according to claim 1, wherein the first metal terminal is provided with a notch. The battery device according to claim 1, wherein a cross-sectional area of the first metal terminal is smaller than a cross-sectional area of the second metal terminal. The battery device according to claim 1, wherein a heat insulating layer is formed on the first metal terminal. The battery device according to claim 1, wherein the diameter of the fusible alloy located on the first metal terminal side is larger than the diameter of the fusible alloy located on the second metal terminal side.

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