JPH11144589A - Manufacture of foil connecting conductor and manufacture of alloy type thermal fuse - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a foil connecting conductor safely weldable to the plate electrode of a super-thin type alloy thermal fuse by welding and connecting a foil conductor to a shaft-like conductor having a width smaller than the width of the foil conductor, a thickness larger than the thickness of the foil conductor and a melting point lower than the foil conductor, and foiling the connections and the shaft-like conductor by compression. SOLUTION: A substantially circular sectional shaft-like conductor 2 having a melting point lower than a copper foil 1 and a sectional area substantially equal to the sectional area of the copper foil 1 is welded to the copper foil 1. For the heating in welding, heating by contact of a heating block, hot air heating, or direct current-carrying heating is employed. The weld part and the shaft-like conductor are pressurized and molded into a foil having the same thickness as the copper foil. The foiling is performed by passing it to a rolling roll having a gap set to the thickness of the copper foil, compressing it by a press or the like. After the foiling, both the lateral sides are trimmed so as to be equal to the copper foil width, whereby a copper foil-low melting point metal foil connected body is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a foil-like connecting conductor useful as a fuse element of an ultra-thin alloy type temperature fuse and a method for manufacturing an alloy type temperature fuse.

[0002]

2. Description of the Related Art In an alloy type temperature fuse, a fuse is used.
A low-melting-point fusible alloy piece is used for the element, and the power supply to the equipment is cut off by fusing the low-melting-point fusible alloy piece due to abnormal heat generation of the equipment, thereby protecting the equipment. In recent years, with the miniaturization of devices, thinner temperature fuses have been required. For example, in a lithium ion secondary battery, it has been proposed that a flat temperature fuse is sandwiched between the end of a positive electrode lid fixed by caulking through a gasket at the upper end of a negative electrode can and the end of a safety valve plate. However, the thickness required for the flat temperature fuse is an ultrathin thickness of 1 mm or less in terms of the size of the battery.

FIG. 6 shows an example of the above-mentioned flat type temperature fuse. Plate electrodes 4 'and 4' are provided above and below an insulating spacer 3 'having a central hole 31'. A low melting point fusible alloy piece 20 'as a fuse element is bridged between the electrodes 4', 4 '. To make the flat temperature fuse ultra-thin, it is effective to make the low melting point fusible alloy piece into a foil shape. For example, a circular section having a diameter of 700 μm has the same sectional area as a section of a foil having a thickness of 100 μm and a width of 4000 μm. By adopting such a foil shape, the thickness of the low melting point fusible alloy piece can be reduced to 1/7, and the temperature hue can be reduced. It is effective to make a low melting point fusible alloy piece into a foil for an ultra-thin alloy.

[0004]

In the alloy type temperature fuse incorporated in the above-mentioned battery, even under normal conditions, thermal stress is applied due to, for example, daily or seasonal temperature changes. In order to ensure stable electrical contact between the plate and the plate electrode, it is necessary to weld the contact point. However, when welding the low-melting-point fusible alloy foil and the plate electrode by abutment of the heating block, the low-melting-point fusible alloy foil is melted quickly, and before the temperature reaches a temperature at which the plate electrode can be welded. The low melting point fusible alloy foil melts,
Welding is very difficult. In contrast, the instantaneous welding, for example, spot resistance welding or laser welding, does not easily cause the fusing, but the welding spot of the low melting point fusible alloy foil is scattered by strong concentrated heat energy, which is satisfactory. Welding cannot be expected.

It is an object of the present invention to produce a foil-like connecting conductor which can be safely welded to an ultra-thin alloy-type temperature fuse plate electrode.

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided a method for manufacturing a foil-shaped connection conductor, comprising: a foil-shaped conductor; a foil having a lower melting point than the foil-shaped conductor; Is characterized in that a shaft-like conductor smaller than the width of the foil-like conductor is connected by welding, and then the connecting portion and the shaft-like conductor are compressed to form a foil. The method for producing an alloy-type temperature fuse according to the present invention comprises the steps of: disposing a low-melting metal foil having a foil-like conductor at both ends, which is produced by the above-described method for producing a foil-like connection conductor, between plate electrodes; The structure is characterized by welding between the plate-shaped conductor and each plate electrode.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 (a) to 1 (c) show an example of a method for manufacturing a foil-like connection conductor according to the present invention. The foil-like connection conductor has a thickness of 50 to 200 μm.
It is a low melting point metal foil connector. In order to manufacture this copper foil / low melting point metal foil connection body, first, as shown in FIG.
An axial conductor 2 having a melting point lower than that of the copper foil 1 and a cross section substantially equal to the cross sectional area of the copper foil 1 (approximately 0.7 to 1.5 times) and having a substantially circular cross section is welded to the copper foil 1. As the heating at the time of welding, heating by contact of a heating block, hot air heating, direct current heating (upset welding), or the like can be used. Next, as shown in FIG. 1B, the welded portion and the shaft-shaped conductor are pressed to form a foil having the same thickness as the copper foil. For the formation of the foil, a method of passing the gap through a rolling roll set to a copper foil thickness, a method of compressing with a press, and the like can be used. After completion of the formation of the foil, as shown in FIG. 1C, both ends of the width are trimmed so as to be equal to the width of the copper foil, thereby completing the production of the copper foil / low melting point metal foil connection body. . In the above, a metal foil having a higher melting point than the low melting point metal foil other than the copper foil, for example,
The use of aluminum foil is also possible. In addition, the foil-shaped conductor has a low-melting-point shaft conductor having a rectangular cross section (for example, a square or a rectangle) or an ellipse whose thickness is larger than the thickness of the foil conductor and whose width is smaller than the width of the foil conductor. Can also be used.

In the method for manufacturing a foil-shaped connection conductor according to the present invention, the low-melting-point metal conductor is welded to the high-melting-point foil conductor in a shaft shape before being formed into a foil, and the same cross-sectional area is used. The shaft shape is higher in strength than the foil shape, and even if the low melting point metal softens at the welding temperature, it is less likely to break under the shaft shape than the foil shape. Can be easily welded by preventing the low-melting metal conductor from being melted.
Furthermore, since the shaping of the welded low-melting metal conductor is a rolling process and does not receive a tensile force, the low-melting metal conductor can be easily formed into a foil without breaking. Therefore, according to the present invention, a foil-like connection conductor such as a copper foil / low-melting-point metal foil connection conductor can be easily manufactured.

FIG. 2 shows an example of a thin temperature fuse using a copper foil / low melting point metal foil connecting conductor A manufactured according to the present invention as a fuse element. In FIG. 2, reference numeral 3 denotes an insulating spacer having a central hole 31, which uses a heat-resistant plastic film (for example, polyethylene terephthalate, polyamide, polyimide, polyphenylene sulfide, etc.) or a ceramic plate. it can. Reference numerals 4 and 4 denote plate electrodes fixed to the upper and lower surfaces of the insulating spacer 3 with an adhesive 41, and a metal foil such as a copper foil can be used. a
Denotes a foil-shaped connection conductor manufactured according to the present invention, which has a structure in which copper foil pieces 10 are provided at both ends of a low-melting metal foil 20, the low-melting metal foil 20 is accommodated in a central hole 31, and each copper foil piece 10 is It is sandwiched between the upper and lower end surfaces of the insulating spacer 3 and the respective plate electrodes 4, and the copper foil pieces 10 and the respective plate electrodes 4 are welded by spot resistance welding or laser welding. It is. Reference numeral 5 denotes a flux filled in the central hole 31.

In order to produce the alloy type temperature fuse shown in FIG. 2, copper foil pieces 1 at both ends manufactured according to the invention of claim 1 are used.
The low-melting metal foil 20 having 0 is placed in the central hole 31 of the insulating spacer 3 and the hole 31 is filled with the flux 5, and then the plate electrode 4 is attached to the upper and lower surfaces of the insulating spacer 3 with the adhesive 41. And each copper foil piece 10 is clamped between each plate electrode 4 and the upper and lower surfaces of the insulating spacer 3, and then each copper foil piece 10 and each plate electrode 4 are spot-resistant. The welding is performed by welding or laser welding, and the production of the alloy-type temperature fuse is completed. The copper foil piece 10 and the pre-
Since welding with the electrode 4 is performed instantaneously and in a spot manner, heat conduction to the low melting point metal foil 20 during this welding can be sufficiently eliminated, and the low melting point metal foil 20 can be stably held. Therefore, the alloy type temperature heater manufactured by the invention of claim 2 is provided.
In the case of the alloy type temperature fuse shown in FIG. 6, the low melting point metal foil 20 'is formed by welding the spot directly to the plate electrode 4' by concentrating heat energy in a spot manner. Scattering of the melting point metal can be eliminated, and stable electrical conduction can be ensured through safe welding between the low melting point metal foil and the plate electrode.

FIG. 3 shows another example of the alloy type temperature fuse manufactured according to the second aspect of the present invention. In order to manufacture the alloy type temperature fuse according to the second aspect of the present invention, the low melting point metal foil 20 having the copper foil pieces 10 at both ends manufactured according to the first aspect of the present invention is used as an insulating spacer. 3
The central hole 31 is filled with a flux 5 and the plate electrodes 4 are fixed to the upper and lower surfaces of the insulating spacer 3 with an adhesive 41. 4 and each copper foil piece 10 are welded by spot resistance welding, laser welding, or the like, whereby the alloy mold temperature hue is welded.
The production of the game ends.

The alloy type temperature hue shown in FIG. 2 and FIG.
The thickness of the plate electrode 4 is 50 μm to 200 μm.
μm, the thickness of the low melting point metal foil 20 and the copper foil piece 10 is 50 μm.
m to 200 μm, and the thickness of the insulating spacer 3 is almost 100 to
900 μm, the thickness of the adhesive layer 41 is 50 to 200 μm,
The total thickness is approximately 300 to 1000 μm, and as shown in FIG. 4A and FIG. Used in. In FIG. 4, reference numerals 61 and 62 denote an upper end portion 631 of a negative electrode can 63 and a positive electrode lid and a safety valve plate whose outer periphery is fixed via a gasket 64, and a denotes an annular ultra-thin temperature fuse sandwiched therebetween. Are respectively shown. Numeral 31 indicates a central hole of the insulating spacer.

As shown in FIG. 5, an annular part is an ultra-thin temperature fuse a and another part b is an ultra-thin temperature fuse a.
It can also be used in the form of an auxiliary insulating spacer having the same thickness as the above.

[0014]

According to the present invention, the thickness is 50 to 200 μm.
And a high-melting-point metal foil of the same thickness welded to both ends of the ultra-thin low-melting-point metal foil can be easily manufactured, and such a connecting conductive foil is used as a fuse element of a flat temperature fuse. By doing so, it is possible to manufacture an ultra-thin temperature fuse having a thickness of 1000 μm or less.

[Brief description of the drawings]

FIG. 1 is a drawing showing a method for manufacturing a foil-shaped connection conductor according to the present invention.

FIG. 2 is a drawing showing an example of a temperature fuse using a foil-shaped connection conductor manufactured according to the present invention.

FIG. 3 is a drawing showing another example of a temperature fuse using a foil-shaped connection conductor manufactured according to the present invention.

FIG. 4 is a drawing showing an example of a state in which the temperature fuse shown in FIG. 2 or 3 is installed in a battery.

FIG. 5 is a drawing showing another example of a state in which the temperature fuse shown in FIG. 2 or 3 is installed in a battery.

FIG. 6 is a view showing a conventional flat temperature fuse.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Foil conductor 2 Axial conductor A Copper foil / low melting point metal foil connection conductor 10 Copper foil 20 Low melting point metal foil 3 Insulating spacer 31 Central hole of insulating spacer 4 Plate electrode

Claims (2)

[Claims] 1. A method for welding a foil conductor to a shaft conductor having a lower melting point than the foil conductor, a thickness larger than the thickness of the foil conductor, and a width smaller than the width of the foil conductor. , And thereafter, the connecting portion and the shaft-shaped conductor are compressed into a foil to form a foil-shaped connecting conductor. 2. A low-melting metal foil having a foil-like conductor at both ends, which is produced by the method for producing a foil-like connection conductor according to claim 1, is disposed between the plate electrodes. A method for producing an alloy-type temperature fuse, characterized in that the temperature is welded to a metal electrode.