JP3254261B2 - Method of manufacturing battery rupture - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealed battery, and more particularly, to a novel method of manufacturing a rupture which operates immediately when the internal pressure of a battery can reaches a certain value or more and prevents the internal pressure of the battery can from increasing. it relates to.

[0002]

2. Description of the Related Art Recently, batteries such as lithium batteries and lithium ion batteries have been widely used in portable electronic devices and the like. By the way, in order to prevent the internal pressure from rising and the battery can exploding at the time of abnormality such as short circuit or heating, the generated gas is released outside the can when the internal pressure of the battery can reaches a certain value or more. A mechanism is installed for

[0003] For example, Japanese Patent Application Laid-Open No.
No. 252, a method of making an incision-type cut in a part of a battery can, a method of providing an opening in a part of a battery can, welding a metal foil to the part, and sealing the part.
A method has been devised for mounting a spring-type holding valve that opens when the internal pressure reaches a certain value or more.

[0004]

However, such a conventional safety mechanism has various problems.

[0005] That is, in the case of the method of making an incision-type notch, it is difficult to control the operating pressure, and the operation may not be performed until the internal pressure of the battery can becomes considerably high, so that a safety problem remains.

In the method of providing an opening in a part of a battery can and welding and sealing a metal foil to the part, there is a technical difficulty in welding a thin metal foil, and the metal foil is damaged during welding. Therefore, there is a problem that the operating pressure is not stable, or a pinhole or the like is generated and the sealing property is impaired. Also, in the case of the method of mounting a spring type holding valve, the sealing performance is not perfect, and there are problems such as mixing of water and volatilization of the electrolyte, and it is difficult to guarantee the performance of the battery.

The present invention has been made in view of the above points, and by devising a rupture structure in which the operating pressure is stable and the hermeticity is complete, gas can be prevented even in the event of an abnormality such as an increase in internal pressure. It is an object of the present invention to provide a battery which can prevent the battery can from being expelled and exploded.

[0008]

According to the present invention, there is provided a method for manufacturing a semiconductor device, comprising:
a metal foil having a thickness of 0.1 to 5.0 mm having an opening of at least 5 mm ² or more is clad.
The battery can lid is made using the clad material obtained by
By mounting the manufactured rupture, when the internal pressure of the battery rises, it operates accurately to prevent the battery from rupture or the like.

Referring specifically to the drawings, the drawings show an example in which the battery rupture of the present invention is provided on a battery can lid.

FIG. 1 is a plan view of this battery can lid material, and FIG. 2 is a sectional view taken along line AA in FIG. As shown in the drawing, a positive electrode pin 4 is provided via an insulating layer 5 at the center of a battery can lid material in which a metal plate 2 having an opening 3 and a metal foil 1 are clad.

[0011]

The metal foil used in the present invention must have a thickness in the range of 1 to 40 μm. Preferably, it is in the range of 3 to 30 μm, more preferably in the range of 5 to 25 μm.

[0012] The thickness of the metal foil greatly affects the operating pressure.
That is, when the thickness of the metal foil is less than 1 μm, the operating pressure becomes too low, which is preferable from the viewpoint of safety. Conversely 4
When a metal foil having a thickness exceeding 0 μm is used, the operating pressure becomes too high, which causes a problem in safety.

Although the material of the metal foil is not particularly limited, Ni, Al, Cu, SUS, Ti, Fe
And the like.

Next, the rupture structure referred to in the present invention can be obtained by cladding the above metal foil and a metal plate having a thickness of 0.1 to 5.0 mm having an opening of at least 5 mm ² or more. The method of cladding is not particularly limited. For example, Japanese Patent Publication No. 1-16,
No. 597, Japanese Patent Publication No. 1-35,918, Japanese Patent Publication No. 1-42,799, the method disclosed in Japanese Patent Publication No. 1-33,599 and the like are employed.

At this time, the metal plate must have at least an opening of 5 mm ² or more. If it is less than 5 mm ² , even if the rupture operates at a predetermined pressure, the area of the opening is too small, gas is not released smoothly, pressure remains in the battery can, and safety problems remain, which is preferable. Absent.

The thickness of the metal plate must be in the range of 0.1 to 5 mm. When the thickness is less than 0.1 mm, a disadvantage that the mechanical strength is weak is not preferable.

When the thickness exceeds 5 mm, although the strength is sufficient, the weight is unnecessarily increased, which is not preferable.

Although the material of the metal plate is not particularly limited, Ni, Al, Cu, SUS, Ti, Fe
And the like.

The method of attaching the material clad by the above method to a battery is not particularly limited, but may be a method of welding to a battery can side wall, a battery can bottom, a battery can lid, or a caulking method. And the like.

Generally, it is most rational to use the clad material as a battery can lid material.

[0021]

The present invention will be described in more detail with reference to the following examples.

Example 1 A battery can lid as shown in FIG. 1 was manufactured using a clad material of a SUS foil 1 having a thickness of 10 μm and a SUS plate 2 having an opening 3 having a size of 6 mm ² .

The hydrostatic breaking pressure of the rupture portion of the battery can lid was measured.

The results were as shown in Table 1. The measurement was performed at n = 10.

Examples 2 to 5, Comparative Examples 1 and 2 In Example 1, the thickness of the SUS foil, the thickness of the SUS plate,
Except that the area of the opening was changed as shown in Table 1, the same operation was performed. The rupture breaking pressure at that time is also shown in Table 1.

[0026]

[Table 1]

[0027]

As described above, the rupture in the condition range of the present invention can be set to an arbitrary operating pressure by selecting the thickness of the metal foil, and the variation of the set operating pressure is very small. Very useful as a safety mechanism.

[Brief description of the drawings]

FIG. 1 is a plan view of an example of a battery can lid having a battery rupture of the present invention;

FIG. 2 is a sectional view taken along line AA of the battery can lid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal foil 2 Metal plate 3 Metal plate opening 4 Positive electrode pin 5 Insulating layer

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasufumi Minato 1-31-1 Yoko, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Asahi Kasei Kogyo Co., Ltd. (72) Tsutomu Kinatsuna 3-22- Kirigaoka, Midori-ku, Yokohama-shi, Kanagawa-ken 14-202 (56) References JP-A-60-165040 (JP, A) JP-A-2-284350 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01M 2/12 101

Claims (1)

(57) [Claims] 1. A metal foil having a thickness of 1 to 40 μm, an opening of at least 5 mm ² or more, and a thickness of 0.1 to 5.0 m
m obtained by cladding a metal plate
A method for producing a battery rupture, comprising producing a battery can lid using a pad material .