JPH05174805A - Improvement in battery - Google Patents

Abstract

PURPOSE: To provide a battery in which reliability is high, a pressure relief property occupying only a small place is equipped in the battery, and gas pressure is released without damaging the battery. CONSTITUTION: A battery is equipped with a one-direction relief valve which releases gas stored in the battery 10 when inside gas pressure reaches a predetermined value, and is closed when the gas pressure becomes a predetermined value or less. The battery comprises a relief hole 26 which is arranged in the recessed portion of a housing, an elastic member 28 which is arranged in the recessed portion and at least one part of which is on the relief hole 26, and a cover plate 32 which closes the relief hole 26 normally and when the pressure exceeds the predetermined pressure, the elastic member 28 is caused to deform so as to open the relief hole 26.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to batteries, and more particularly, but not exclusively, to button-cell batteries.

[0002]

Batteries such as nickel cadmium button cells are known. Such a battery can be used in a power calculator, a television remote control unit, and the like. One problem with these batteries is that they have a large electromotive force (EM).
F) is the internal pressure created by the accumulation of gas generated as a result of the electrochemical reaction that gives rise to F). This is clearly undesirable, and it is common to provide battery relief to allow such gas to escape.

The conventional method for releasing the battery is to provide a weakened portion in the case of the battery, and weaken the portion when the internal pressure of the battery exceeds a predetermined pressure. Is to explode. However, this has the drawback of making the battery dry and causing it to fail relatively early.

[0004]

SUMMARY OF THE INVENTION One object of the invention is to provide a battery in which the gas pressure can be released without causing any damage to the battery.

Another object of the present invention is to provide a pressure relief feature that is reliable and occupies a small space in the battery.

[0006]

SUMMARY OF THE INVENTION According to one aspect of the present invention, a wall has a housing with a one-way relief valve that releases gas above a predetermined pressure. A battery is provided that is adapted to open at the same time and close when gas pressure is reduced.

One advantage of the present invention is that the accumulated pressure in the battery can be released while the battery is in an intact condition, without drying the battery and causing failure. It is something that will be done.

The relief valve has a relief hole disposed in a recess in the housing, an elastic member substantially disposed in the recess and at least a portion of which is above the relief hole, and the elastic member is deformed. And a cover adapted to normally close the escape hole and to deform the elastic member to open the escape hole when a predetermined pressure is exceeded. The deformable elastic member includes a dish-shaped disc having a convex side facing the relief hole. This allows a reliable arrangement that requires only a small space.

Further objects, features and advantages will become apparent from the following description of a preferred embodiment of the invention, given by way of non-limiting example.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a battery, generally designated 10, includes a metal body can 12, which is substantially a circular cylinder. A gasket 14 is inserted inside the body can, the gasket being made of an electrically insulating material. The internal components of the battery are located in section 16 and are not shown here. However, one of ordinary skill in the art will recognize that these internal components may be similar to those found in other button cell batteries.

A contact spring 18 is located on top of internal components within the battery portion 16. Top cap 2
A zero is attached to the top of this contact spring. The perimeter 22 of this cap is located in a groove 24 in the gasket. In this way, the portion 16 of the battery is sealed away from the aperture 26 located in the top cap. A relief plug 28, which is in the form of a slightly concave plastic disc, is located over the hole 26 in the top cap portion 30. The cover plate 32 is this part 3
Mounted on the zero and spot welded at four points (only two of which are shown). Mounting the cover plate 32 in this manner causes the relief plug 28 to be slightly compressed to seal the hole 26 and thus the portion 16.

In use, the internal components of the battery undergo an electrochemical reaction. As already mentioned, these reactions generate a gas which gradually causes an accumulation of gas pressure in the portion 16. At a predetermined pressure, these gases are sufficiently high in pressure to cause the relief plug 28 to deform. This flattens the relief plug 28 and reduces its concave shape, which allows gas to enter the portion 30, ie the space between the top cap and cover plate. Since the top cap and cover plate are only spot welded at four points, the gas is allowed to pass through other locations on this surface between these four points. As a result, the gas pressure in the portion 16 is released. When the pressure drops below a predetermined pressure value to open the relief plug, the relief valve is closed and the battery continues to operate normally. The act of letting gas escape from portion 16 occurs whenever the pressure in portion 16 reaches the predetermined value required to open the relief plug.

A PVC cover 36 of electrically insulating material may be attached to the battery to insulate the positive contact area of the battery from the substrate.

The following battery components, namely contact springs, cover plates, top caps and body cans are preferably made of metal. Both the gasket and the relief plug are preferably made of insulating material. However, the relief plug can be replaced by any resilient material that deforms due to the pressure exerted through the hole 26 to open the hole.

Although the present invention has been described with reference to nickel cadmium batteries, the basic design is applicable to any other type of battery in which gas accumulation in portion 16 likewise occurs. You must be careful that you can do it.

The PVC cover is of any nature that may not be provided whether or not the area of the positive contact needs to be insulated from the battery body.

In some applications, the top cap 2
It is also possible to provide one or more similar relief valve assemblies as described above, which are arranged on the surface of zero.

In the illustrated assembly, the cover plate is spot welded to the top cap at four locations, which merely indicates the desired number of welds. More or less spot welds can be applied depending on the required application.

In the portion where spot welding is performed,
It is also possible that the metal structure on one of these surfaces is slightly deformed to allow gas to escape from the battery between the top cap and cover plate.

It should be understood that many modifications and developments can be made without departing from the spirit and scope of the invention as limited by the claims.

[0021]

Since the present invention is constructed as described above, it has a reliable, pressure-relieving property that occupies a small space in the battery, and the internal structure without causing any damage to the battery. It is possible to obtain an excellent effect of providing a battery in which gas pressure can be released.

[Brief description of drawings]

1 is a cross-sectional view of a battery according to the present invention.

2 is a sectional view of the battery of FIG. 1 taken along section A;

FIG. 3 is a top view of the battery of FIG.

[Explanation of symbols]

 10 Battery 12 Main Body Can 14 Basket 16 Part in Battery 18 Contact Spring 20 Top Cap 24 Groove in Gasket 26 Hole in Top Cap 20 28 Disc-shaped Escape Plug 30 Part of Top Cap 20 32 Cover Plate 36 PVD Cover

Claims (9)

[Claims] 1. A battery having a housing with a one-way relief valve on one wall, wherein the relief valve is opened to release gas above a predetermined pressure from the housing, the gas pressure The battery is designed to be closed when the battery is reduced. 2. The battery is a dry cell.
Battery described in. 3. The battery according to claim 1, wherein the battery is a nickel-cadmium battery. 4. The battery according to claim 1, wherein the battery is a button cell. 5. A battery according to claim 1 provided with more than one relief valve. 6. A relief hole in which said relief valve or a respective relief valve is arranged in a recess in said housing, and a relief hole substantially arranged in said recess, at least a part of which is above said relief hole. An elastic member and a cover configured to normally close the escape hole, but when the predetermined pressure is exceeded, the elastic member is deformed to open the escape hole. The battery according to claim 1, comprising: 7. The battery of claim 6, wherein the cover is secured to the housing at one or more points. 8. The battery according to claim 7, wherein the fixing of the cover to the housing is performed by spot welding at the points or the respective points. 9. The battery according to claim 6, wherein the deformable elastic member includes a dish-shaped disc having a convex side portion facing the escape hole.