JP2560364Y2 - Sealed lead-acid 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 sealed lead-acid battery, and more particularly, to a sealed lead-acid battery in which three or more unit cells each comprising an electrode group wrapped in a synthetic resin film or sheet are assembled. Related to storage batteries.

[0002]

2. Description of the Related Art With the miniaturization of portable electric equipment on which a secondary battery is mounted, there is a strong demand for miniaturization of the secondary battery itself. As a lead storage battery corresponding to such miniaturization, a unit cell formed by enclosing an electrode plate group (a structure in which a positive electrode plate, a negative electrode plate, and a separator separating the both electrode plates are stacked) with a synthetic resin film or sheet is used. Japanese Patent Application Laid-Open No. Sho 61-114446 proposes a structure in which layers are stacked in the thickness direction and housed in a rigid case in a pressurized state.

[0003]

[Problems to be Solved by the Invention] In the above-mentioned technology, the rigid case is heavy and the thickness is also thick. It is in a situation where it is unavoidable. In such situations, due to the case deflection,
A gap is formed between the side wall surface of the case and the unit cell. As a result, pressurization of the stacked unit cells at both ends becomes insufficient, and the performance of the unit cells at both ends deteriorates quickly between the central unit cell and the unit cells at both ends, resulting in a difference in battery life. The problem to be solved by the present invention is to make it possible to sufficiently press all the stacked unit cells when the stacked unit cells are housed in a case and pressed, even if the case is slightly bent.

[0004]

In order to solve the above-mentioned problems, a sealed lead-acid battery according to the present invention has the following configuration. A group of electrodes comprising a positive electrode plate, a negative electrode plate, and a separator for separating the two electrode plates is wrapped with a synthetic resin film or sheet to form a unit cell. Three or more of the unit cells are stacked in the thickness direction and housed in a case in a pressurized state. Only the both end cells of the stacked unit cells are separately pressed in the thickness direction.

[0005]

In the sealed lead-acid battery according to the present invention, since only the unit cells at both ends of the unit cells stacked three or more are separately pressed, the rigidity of the case is reduced and the case is slightly bent.
The pressure on the unit cells at both ends does not decrease. Even if the rigidity of the case is reduced and the thickness of the case is reduced to reduce the size and weight, the pressure is applied to all the stacked unit cells well, and the life of each unit cell varies. It is possible to reduce the size.

[0006]

FIG. 1 shows an embodiment of the present invention.
The unit cell 1 is obtained by enclosing an electrode group with a synthetic resin film or sheet having gas barrier properties. After pre-welding the electrode lugs of the electrode group to the terminal 2 insert-molded in the polypropylene molded product, the upper end of the synthetic resin film or sheet enclosing the electrode group is thermally welded to the polypropylene molded product and sealed, The unit cell is 1.

[0007] Five unit cells 1 are stacked in the thickness direction to form an assembled battery with a voltage of 10 V which is connected in series. The unit cells at both ends of the stack are each formed of a stainless steel band 3 having a thickness of 0.3 mm. Two places were tightened and pressed in the thickness direction. The five unit cells thus laminated were housed under pressure in a case 4 made of aluminum having a thickness of 0.4 mm. In the stacked central unit cell, adjacent unit cells come into close contact with each other and are always pressed. However, even when the case 4 is bent and a gap is formed between the unit cells at both ends and the side wall surface of the case 4. The pressure applied to the unit cells at both ends does not decrease due to the action of the band 3.

When the unit cells at both ends are fastened with a band, a plate-like body is brought into contact with the side facing the case side wall, so that when the case is bent, the pressing force on the unit cells at both ends is further increased. It will be good.

[0009]

As described above, in the sealed lead-acid battery according to the present invention, when three or more unit cells stacked in the thickness direction are accommodated in a case in a pressurized state, even if the case is slightly bent, both ends of the battery can be used. By maintaining the pressure applied to the electrode plate group of the unit cell, the life of the entire unit cell housed in the case can be made uniform. Since some bending of the case can be tolerated, the thickness of the case can be reduced and the weight can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a sealed lead-acid battery according to the present invention.

[Explanation of symbols]

 1 is a unit cell 2 is a terminal 3 is a band 4 is a case

Continuation of the front page (72) Inventor Toshiichi Iwase 2-1-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Examiner, Shinkobe Electric Co., Ltd. Chikako Aoki (56) References JP-A-60-195865 (JP, A ) Actually open 60-124856 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A unit cell comprising a positive electrode plate, a negative electrode plate and an electrode plate group formed by laminating separators for separating the two electrode plates, wrapped with a synthetic resin film or sheet, and three or more unit cells are laminated in the thickness direction. In the case where the case is housed in a pressurized state, the case has a strength that bends in the pressurized state.
There is a gap between the unit cells at both ends and the side wall of the case.
A sealed type lead-acid battery, wherein only the cells at both ends of the stacked unit cells are separately pressed in the thickness direction.