JPH0471309B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to improvements in sealed lead-acid batteries, and more particularly to improvements in a case for housing a single cell or a plurality of cells with an exterior.

Construction of conventional examples and their problems As a measure to reduce the cost of storage batteries, monoblock cases molded from synthetic resins such as ABS resin have been replaced with thermoplastic resins in the form of films or sheets, such as polyethylene 1, as shown in Figure 1. Several proposals have been made to replace the bag-like exterior body 2 made of. In this case, an electrode plate group 7 consisting of a positive electrode plate 4 with a resin-coated pole post 3 welded to the upper part, a negative electrode plate 5 with a pole post 3' welded to the upper part, and a separator 6 is made of an acid-resistant and heat-weldable material. They are inserted through the bottom opening 2a of a film-like or sheet-like synthetic resin bag-like exterior body 2, and the tips of the pole columns 3, 3' are made to protrude outward from the openings 2b, 2c at the top of the bag-like exterior body 2. Next, the bag-like exterior body 2 and the pole pillar 3,
3' and the bottom opening 2a are sealed by heat welding. After sealing, a predetermined amount of electrolyte was injected through the opening 2e of the unwelded convex portion 2d, which served as a safety valve of the bag-like exterior body, to form a battery. However, since the material of the exterior body is film-like or sheet-like, it easily deforms and has no self-retention properties at all. In recent years, in sealed lead-acid batteries, retainer type batteries in which a liquid electrolyte is retained in a mat-like separator made of glass fiber or the like have been increasingly used. However, since these separators have elasticity, there is a problem that the capacity cannot be fully extracted unless a certain pressure is applied.For this reason, cases made of ABS resin or polypropylene are used as shown in Figure 2. A plurality of cells were electrically connected and housed in 11, covered with a cover 13 to which terminals 12 were attached, and fixed with adhesive or the like. However, in this case, the case 11 becomes thicker. There were problems such as the electrode group being easy to move.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and aims to provide a lightweight and highly reliable sealed lead-acid battery at a low cost.

Composition of the Invention In order to achieve the above-mentioned object, the present invention is made by sandwiching an electrode group consisting of a positive electrode plate, a negative electrode plate, and a separator between film-like or sheet-like synthetic resins that are acid-resistant and heat-weldable. The synthetic resin around the electrode plate group is thermally welded leaving some unwelded parts to form the exterior body, and the single cell or multiple cells are placed in a separate case with the unwelded parts serving as injection ports and safety valves. In a housed sealed lead-acid battery, a plurality of ribs, grooves, and other irregularities are formed on the inner surface of the case that contacts the electrode plates of a single cell or multiple cells in a direction transverse to the safety valve. The formation of this unevenness increases the strength of the case, suppresses the thinning of the case and the movement of the electrode plate group, especially in the direction of the safety valve within the case, and prevents closure due to bending of the safety valve part. .

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

Figure 3 shows an electrode plate group 7 consisting of one positive electrode plate 4, two negative electrode plates 5, and a glass fiber mat 6, as in the conventional case, with a thickness of 0.3 mm, which is acid-resistant and heat-weldable.
Insert it through the bottom opening 2a of the bag-like exterior body 2 made of two polyethylene films of mm size, take out the tips of the pole columns 3, 3' from the openings 2b, 2c at the top of the bag-like exterior body 2, and then The bag-like exterior body 2 and the pole pillars 3, 3'
and between the films at the bottom opening 2a from the outside using a heat welding press to weld the polyethylene films to each other to generate electricity, and then pour a predetermined dilute sulfuric acid electrolyte from the partially unwelded part 2d. It is injected into a battery. After preparing a plurality of these batteries and connecting the pole columns of the batteries, a plurality of ribs 1 are formed on the inner surface of the battery, as shown in FIG.
It is housed in a two-part case 9 made of ABS resin, polypropylene, or the like with a 0. Also, a hole 11 is provided in the terminal drawer part of this case 9, and a hole 11 is provided in the terminal drawer part of this case 9,
was exposed from here and used as a terminal. Next, the other case 9', which has a plurality of ribs 10' formed on its inner surface like the case 9, has the pole post 3' exposed through the hole 11' of the terminal drawer part, and this case 9' is replaced with the case 9'.
By fitting them together, they become integrated as shown in FIG. 5, and the electrode plate group 7 is held and fixed by the ribs 10 from both left and right sides.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

(1) The strength of the case itself can be increased by providing multiple unevenness on the inner surface of the case, and the thickness has been reduced by 2/3 compared to previous cases without unevenness.
The weight of the case can be reduced by 1/2,
Material costs can be reduced.

(2) Provide multiple unevenness in the direction across the safety valve,
Since the electrode plate group is sandwiched and fixed from the left and right sides by the unevenness, movement of the electrode plate group, especially in the direction of the safety valve, can be prevented after the case is stored, and closure due to bending of the safety valve does not occur. Furthermore, it is possible to prevent the film or sheet from tearing when storing the cell in the case.

(3) If the internal pressure of the battery increases due to charging, etc.
In the part of the electrode plate group arranged to face the inner surface of the case in the recessed part excluding the convex parts such as ribs, the electrode plate swells to fit into the recessed part and the film separates from the outside of the electrode plate, so that the negative electrode plate The absorption of oxygen gas from the side of the film is improved, the gas dissipation ability is improved, the amount of gas released to the outside of the battery is reduced, and the overcharge resistance is improved.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view of a conventional sealed lead-acid battery using a bag-like exterior body, Fig. 2 is a perspective view of a storage case that stores the battery, and Fig. 3 is a perspective view of a case according to the present invention. FIG. 4 is a partially cutaway perspective view of a sealed lead-acid battery using a bag-like exterior body in an example, and FIG.
FIG. 5 is a perspective view of a completed battery in which the same battery is housed inside a case. 2...Bag-shaped exterior body, 3,3'...Pole pillar, 4...
Positive electrode plate, 5...Negative electrode plate, 6...Separator, 7...
...Electrode plate group, 9,9'... Storage case, 10... Rib.

Claims (1)

[Claims] 1 An electrode plate group consisting of a positive electrode plate, a negative electrode plate, and a separator is sandwiched between acid-resistant and heat-weldable film-like or sheet-like synthetic resin bodies, and the synthetic resin body around the electrode plate group becomes a part of it. Leave the unwelded part, heat weld everything else, and package the single cell or multiple cells with the unwelded part serving as the injection port and safety valve, and store it in a separately prepared two-piece case made of synthetic resin. A sealed lead-acid battery, in which a plurality of unevenness such as ribs or grooves are formed in a direction transverse to the safety valve on the inner surface of each case that comes into contact with the electrode plate of a single cell or multiple cells, and the thickness of the cell is A sealed lead-acid battery characterized by a case that is split in two directions and assembled into an integrated unit.