JPH04149957A - Sealed-type lead secondary battery - Google Patents

Abstract

PURPOSE:To improve the reliability of air-tightness by containing and sealing a group of electrode plates attached to a thermally plastic resin plate, in which a safety valve system is installed, in a bag-like casing body by thermally melting and sticking the outer periphery of a film-like synthetic resin. CONSTITUTION:A resin plate is a thermally plastic resin having terminal-piercing sealing parts 6, 6' which seal an anode and a cathode terminals 3, 3' connected with an anode and a cathode and a safety valve system 7 composed of a cylindrical gas discharging part and a safety valve made of rubber and attached to the gas discharging part. In order to improve the properties of thermal melting and sticking to a film bag-like casing body 1, extruded parts 8 are formed in the periphery of the resin plate. Open parts 9, 10, 10' corresponding to the terminal-piercing sealing parts of the resin plate 4 and the safety valve system are previously formed in the bad-like casing body 1 and the film-like synthetic resin 5 and the resin plate 4 are pushed to a hot plate to be molten and stuck each other and next, when the film-like synthetic resin is stuck like a bag, the resin plate 4 is so put as to be in the botton inside of the bag-like casing body 1. Finally, a group of electrodes are inserted and the part not yet melted and stuck of the bag-like casing body is thermally melted and stuck.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a sealed lead acid battery, and in particular to an improved film bag-shaped battery case.

BACKGROUND ART Conventional technology and its problems Conventional sealed lead-acid batteries are composed of an electrode plate group consisting of positive and negative electrode plates and a separator, an electrolytic solution, and a container made of synthetic resin that houses these.

With such a structure, different battery cases, lids, etc. are required for each model, and the cost and preparation of molding molds are time-consuming, making it difficult to respond flexibly.

Therefore, recently, lead-acid batteries using a bag-like container made of synthetic resin instead of a synthetic resin container have been proposed.

For example, there is a proposal as shown in FIG. 4 disclosed in Japanese Patent Laid-Open No. 60-230354. In this method, the electrode plate group 2 is thermally welded around the opening of a bag-like exterior body made of sheet-like or film-like synthetic resin, leaving an unwelded part at the opening.

Although airtightness is maintained by thermally welding it to the housing 1, it requires complicated processing and techniques, and there are also doubts about its reliability. In addition, in order to solve this problem, we have developed
In the device disclosed in the above issue, positive and negative electrode terminals are inserted, and the periphery of a synthetic resin cap that is integrally molded including the safety valve mechanism and the opening of a bag-like exterior body containing a group of electrode plates are heated. Something has been proposed that has settled down. However, in this case, it is difficult to thermally weld the area around the opening at the same time, causing wrinkles and poor airtightness.

Means for Solving the Problems The present invention solves the above-mentioned problems of sealed lead-acid batteries, and provides a sealed lead-acid battery equipped with a bag-like exterior body made of a film-like synthetic resin that has excellent airtightness and mass productivity. It is something to do.

That is, at least the outer periphery of the upper surface of the thermoplastic resin plate provided with the terminal penetration sealing part and the safety valve mechanism part is heat welded to a film-like synthetic resin, the electrode plate group is attached to the resin plate, and the electrode plate group is attached to the film. It is housed and sealed inside a bag-like exterior body formed by thermally welding the outer periphery of a synthetic resin.

Example The present invention will be explained below based on examples.

FIG. 1 is a perspective view showing an embodiment of a sealed lead-acid battery according to the present invention, in which a group of electrode plates 2 is housed in a bag-like exterior body 1 made of a heat-weldable synthetic resin film. The positive and negative terminals 3.3' connected to the positive and negative electrode plates are sealed with terminal through-hole sealing portions 6, 6' shown in FIG. Note that the sealing parts 6 and 6' are sealed in advance.

A negative if child may be inserted.

FIG. 2 is a perspective view of the resin plate 4 in FIG.
It is made of thermoplastic resin and has terminal penetration sealing parts 6, 6' for sealing the positive and negative terminals connected to the negative electrode plate, and a safety valve mechanism part 7 in which a rubber safety valve is attached to a cylindrical exhaust part.

Furthermore, it is preferable to provide projections 8 around the resin plate in order to improve thermal weldability with the film bag-like exterior body.

As shown in FIG. 3(1), the bag-like exterior body 1 is first prepared with openings 9, 10, and 10' corresponding to the terminal penetration sealing part and the safety valve mechanism part of the resin plate 4, and is made of film-like synthetic resin. 5 is pressed against the resin plate 4 and the hot plate and then welded, and then as shown in FIG. Heat weld it so that it is placed on the inner surface. Finally, the electrode plate group was inserted, and the unwelded portion of the bag-like exterior body was heat welded. Note that the electrode plate group may be wrapped in a film-like synthetic resin and then heat welded on three sides. In the example, in order to prevent gas permeation and increase film strength, a laminate film was used in which the film-like synthetic resin had a polyethylene terephthalate layer as the outermost layer, a polypropylene layer on the welding surface, and a polyvinylidene chloride layer between these layers.

All of the above thermal welding can be easily carried out using a flat hot plate, and the welding can be performed satisfactorily with high reliability.

Effects of the Invention As is clear from the above-mentioned examples, the sealed lead-acid battery of the present invention does not require complicated processing compared to the conventional ones, and can have extremely high airtight reliability, and its industrial value is Very large.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the sealed lead-acid battery of the present invention, FIG. 2 is a perspective view of the resin plate 4 in FIG. 1, and FIG. FIG. 4 is a perspective view of a conventional sealed lead acid battery. 1... Bag-shaped exterior body, 2... Plate group, 3.3'...
Positive and negative terminals, 4...Resin plate, 5...Film-like synthetic resin, 6'...Terminal penetration sealing part, 7...Safety valve mechanism part,...Protrusion, 9, 10 10'... Opening part, 11... Hot plate, 12' 13... Welded part Fig.

Claims (1)

[Claims] 1. At least the outer periphery of the upper surface of the thermoplastic resin plate provided with the terminal penetration sealing part and the safety valve mechanism part is heat welded to the film-like synthetic resin that forms the bag-like exterior body of the storage battery, and the electrode attached to the resin plate is 1. A sealed lead-acid battery, wherein a group of plates is housed and sealed in a bag-like exterior body formed by heat-welding the outer periphery of the film-like synthetic resin.