JP2592655Y2 - Thin sealed storage battery - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin sealed storage battery called a so-called film pack storage battery, and more particularly to an improvement in a pressure relief valve structure.

[0002]

2. Description of the Related Art In a conventional film pack type storage battery disclosed in Japanese Patent Application Laid-Open No. 63-174265, an electrode plate group is disposed between two film-shaped or sheet-shaped synthetic resin bodies so as to surround the battery. Joining, providing a pressure-release through hole in one of the two synthetic resin bodies, discontinuously joining the periphery of the pressure-release through hole to the other synthetic resin body to form a partial joint consisting of a plurality of unit joints. The pressure relief valve structure is constructed by making. In addition,
In order to maintain good airtightness, silicone oil may be placed around the small holes.

[0003]

In the conventional structure, the contact portion between the two synthetic resin bodies located near the partial joint between the synthetic resin bodies separates when the internal pressure of the battery rises. Opens and closes when the internal pressure is less than or equal to the external pressure. In the conventional structure, the bending of the synthetic resin body due to the repetition of such valve opening and valve closing is prevented as much as possible by making the partial joint a discontinuous joint composed of a plurality of discontinuous unit joints, Had increased reliability. In this case, the two synthetic resin bodies are separated from each other at a non-joining portion between the unit joining portions constituting the discontinuous joining portion or a non-joining portion between the discontinuous joining portion and the surrounding joining portion due to an increase in the internal pressure. It takes shape. At this time, as the length of the non-joined part becomes longer, the synthetic resin body in that part separates earlier than the other non-joined parts, so that the synthetic resin body of the other non-joined part is pulled. It is hard to separate. Therefore,
Depending on the position of the unit junction, the synthetic resin body in the part where the pressure release through-hole, which is the exhaust hole, is difficult to separate, causing the valve opening pressure to increase, causing the battery to bulge or burst. I do.

[0004] An object of the present invention is to provide a thin sealed battery that can reduce the valve opening pressure.

[0005]

This invention SUMMARY OF THE INVENTION may, through the two sheets of film or retainer and the anode plate and the cathode plate around the joined becomes conductive tank by thermal welding of the sheet-shaped synthetic resin body
The stacked electrode plates are housed, and at least one pressure-release through-hole is formed in one of the two synthetic resin bodies, and the pressure-release through-hole is not connected to the peripheral joint of the battery case. It is an object of the present invention to improve a thin sealed storage battery in which a partial joining portion for partially joining two synthetic resin bodies with an electrode plate group is formed to form a pressure relief valve structure. In the present invention, the partial joints are composed of a plurality of unit joints formed at predetermined intervals, and the length of the non-joint portion between each unit joint, the peripheral joint, and the unit adjacent to the peripheral joint Among the lengths of the non-joining portions between the joining portions, the length of the non-joining portion closest to the pressure-release through hole is made longer than the lengths of the other non-joining portions. Even if the length of the non-joined portion closest to the pressure-release through-hole is increased, other pressures within a range that can obtain a valve-opening pressure sufficient to maintain the function as a safety valve or a pressure-release valve can be obtained. It is longer than the length of the non-joined part. Further, when an oil for improving airtightness such as silicone oil is arranged around the pressure release through hole, free movement of the oil to the electrode plate group side can be suppressed in determining the length of each non-joined portion. Needless to say, it is necessary to determine the length of each non-joined portion as described above.

[0006]

As described above, if the length of the non-joined portion closest to the pressure-release through-hole is made longer than the length of the other non-joined portions, the internal pressure of the pressure-release through-hole is increased when the internal pressure increases. Since the part of the synthetic resin body is most easily separated, the valve is opened at a low pressure. Therefore, it is possible to prevent a problem that the battery case is swollen or ruptured as in the related art.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; FIG. 1 is a schematic partial plan view of an embodiment in which the present invention is applied to a thin sealed lead-acid battery. In this figure, 1
Is a battery case, and the battery case 1 is formed by joining peripheral portions of two film-shaped or sheet-shaped synthetic resin bodies 2 and 2 by heat welding to form a peripheral joint portion 3. In this figure, the two synthetic resin bodies 2 and 2 are drawn as transparent, and the peripheral joint 3 is hatched for easy understanding. Inside the container 1, an electrode group 7 formed by laminating an anode plate 4 and a cathode plate 5 via a retainer 6 is housed and arranged. The output terminal portions 4 a and 5 a of the electrode plate group 7 protrude from the peripheral joint portion 3. A pressure release through hole 8 is formed in the front part of the synthetic resin body 2 at a portion away from the electrode plate group 7. A partial joint portion 9 for partially joining the two synthetic resin bodies 2 and 2 is formed between the plate group 7 and the pressure release valve structure.

The partial joints 9 are composed of unit joints 9a to 9d which are formed so as not to be continuous with each other. The unit joints 9 a to 9 d are formed so as to form a linear row along the side where the terminals of the battery case 1 or the electrode plate group 7 are output, and the peripheral joint between the partial joint 9 and the battery case 1 is formed. Silicone oil (oil for improving airtightness) is used to improve the airtightness at the time of pressure reduction in the area surrounded by the part 3.
10 are filled. This silicone oil is not indispensable. When the internal pressure of the battery rises above a predetermined level, the two synthetic resin bodies 2, 2 between the unit joints are separated and open, and when the internal pressure is equal to or less than the external pressure, the two synthetic resin bodies in this region are opened. The resin bodies 2 and 2 come into close contact and close the valve.

In the figures, a to e denote each unit joint 9a.
To 9d, the length of the non-joined portions and the unit joined portions 9a and 9
The length of the non-joined portion between d and the peripheral joint 3 is shown. In this embodiment, the length c of the non-joining portion (the portion between the unit joining portions 9b and 9c) closest to the pressure-release through hole 8 is changed to the lengths a, b, and It is longer than d and e. With such a dimensional configuration, the valve opening pressure can be reduced. In order to confirm this, the valve opening pressure when the length of each non-joined portion was changed was measured. Table 1 shows the results. The lengths a to e of the non-joined portions are changed within a range where the filled silicone oil 10 does not easily move to the electrode plate group 7 side.

[0010]

[Table 1] From the above results, when the length c of the non-joined portion closest to the pressure-release through hole 8 is the longest, the valve-opening pressure shows a stable low value regardless of the length of the other non-joined portions. When the lengths a, b, d, and e of the other non-joined portions are longer than the length c of the non-joined portion, the valve opening pressure is increased.

In the above embodiment, a plurality of unit joining portions 9a to 9a
9d are arranged in a straight line to form a partial joint 9,
The shape of the partial joint is not limited to the example,
For example, a plurality of unit joints may be formed so as to surround the periphery of the pressure release through hole 8. Even in such a case, the length of the non-bonded portion located closest to the pressure-release through hole 8 among the non-bonded portions formed between the unit bonded portions may be longer than the lengths of the other non-bonded portions.

[0012]

According to the invention present invention, by longer than the length of the unbonded portion of the length of the other non-bonded portion positioned closest to discharge pressure through hole, when the internal pressure rises, release Since the synthetic resin body in the portion where the pressure through hole exists is most easily separated, the valve opening pressure can be reduced. According to the present invention therefore, as in the prior art, can be prevented or blisters battery container, or the occurrence of problem that burst,
A highly reliable pressure relief valve structure can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic partial plan view of an embodiment in which the present invention is applied to a thin sealed lead-acid battery.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery case 2 Film or sheet-like synthetic resin body 3 Peripheral joining part 4 Anode plate 5 Cathode plate 6 Retainer 7 Electrode group 8 Discharge through-hole 9 Partial joining part 9a-9d Unit joining part 10 Silicone oil

Claims (1)

(57) [Scope of request for utility model registration] An anode plate is provided in a battery container formed by joining the periphery of two film-shaped or sheet-shaped synthetic resin bodies by heat welding.
And a cathode plate are housed through a retainer, and at least one pressure-release through hole is formed in one of the two synthetic resin bodies. A thin sealed type in which a partial joining portion that partially joins the two synthetic resin bodies is formed between the pressure releasing through hole and the electrode plate group without being continuous to form a pressure relief valve structure. In the storage battery, the partial junction is formed of a plurality of unit junctions formed at predetermined intervals, and the length of the non-junction between each unit junction and the peripheral junction and the peripheral junction Among the lengths of the non-joining portions between the adjacent unit joining portions, the length of the non-joining portion closest to the pressure-release through hole is longer than the length of the other non-joining portions. Thin sealed battery.