JPS6110866A - Sealed lead storage battery - Google Patents

Abstract

PURPOSE:To improve the reliability of a sealed lead storage battery by preventing any crack or pinhole from occuring in the fused external case by using plates made of lead alloy grids having an R or a tapered area at the corners. CONSTITUTION:Positive and negative plates 4 and 5 are Pb-Ca grids 8 each having a tapered area 8b and small R areas 8c at each corner. Then, a mat-like separator 6 is interposed between the positive and the negative plates 4 and 5 to make a plate group 7. Next, after the plate group 7 is inserted into a sach- like exterior case 2 formed by two acid-proof fusible polyethylene films 1 from the bottom opening 2a of the case 2, its opening 2a and electrode pole sections 3 and 3' are fused and pressed to seal them, thereby constituting a sealed lead storage battery. Because of the above structure, it is possible to improve the reliability of the battery by preventing any pinhole or crack from occuring in the areas of the exterior case 2 corresponding to the corners of the grids 8.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in sealed lead-acid batteries, and particularly to improvements in the shape of the grid.

Conventional configurations and their problems In order to reduce the cost of storage batteries, monoblock cases molded from synthetic resins such as ABS resin have been replaced by thermoplastic resins in the form of films or sheets, as shown in Figure 1.
For example, several proposals have been made to replace the bag-like exterior body with one made of polyethylene. In the figure, 1 is two polyethylene films, and 2 is a bag-like exterior body. In this case, a pole column 3. whose upper part is coated with resin. , 3' are welded to a positive electrode plate 4, a negative electrode plate 5, and a separator 6. An electrode plate group 7 is inserted into the bottom opening 2aJ of a bag-like exterior body 2 made of acid-resistant and heat-weldable polyethylene film: J
Insert it into the upper openings 2b and 2c of the bag-like exterior body 2.
The tips of the pole pillars 3 and 3' are made to protrude outward, and then the gap between the bag-like exterior body 2 and the pole pillar 3 and the bottom opening 2a are heat welded. A battery was prepared by injecting an electrolytic solution through the opening 2e of the unwelded convex portion 2d, which served as a safety valve of the bag-like exterior body. However, since the material of the exterior body is a thin film or sheet, it hits the corner part 8a of the lead alloy grid body 8 of the electrode plate group 7, and a pinhole is created in the bag-like exterior body 2 due to vibration or impact. , airtightness cannot be maintained. Furthermore, in the worst case, there was a problem in which the electrolyte inside the battery leaked out.

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

Structure of the Invention In order to achieve the above-mentioned object, the present invention comprises sandwiching an electrode plate group consisting of a positive electrode plate, a negative electrode plate, and a separator between two film-like or sheet-like synthetic resin bodies that are acid-resistant and heat-weldable. Including, the synthetic resin body around the electrode plate group is rounded at the corner part of the lead alloy lattice body of the electrode plate in a sealed lead-acid battery in which the - part is unwelded and the other part is heat-welded as an exterior body. Or it is characterized by being tapered. By providing this radius or taper, it is possible to eliminate edges at the corners of the lattice body, thereby preventing pinholes and hollows in the bag-like exterior body.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Second
The figure shows a lattice body 8 made of a Pb--Ga alloy with tapers 8b and small radius 8c at the four corners.

Figure 3 shows one positive electrode plate 4 obtained by filling this grid with a paste such as lead oxide, dilute sulfuric acid, etc., and a positive electrode plate 4 obtained by filling the grid with a paste such as lead oxide, dilute sulfuric acid, barium sulfate, etc. Two of the obtained negative electrode plates 5 are combined into an electrode plate group by interposing a mat-like separator 6 made of glass fiber with a fiber diameter of 10 μm or less between them, and the resulting electrode plate group is made to have a thickness that is acid-resistant and heat-weldable. Sa0.
Insert it into the bag-like exterior body 2 made of two 3ml polyethylene films through the bottom opening 2a, and remove the tips of the pole posts 3, 3' 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. d and the bottom opening 2a are heated from the outside using a heat welding press in an attempt to weld the polyethylene films to each other and create electricity;
A predetermined amount of dilute sulfuric acid is injected into the unwelded part 2e provided at one place on the upper part to form a battery.

Effects of the Invention As described above, according to the present invention, by rounding or tapering the corner portion of the lattice body in contact with the bag-like exterior body, it is possible to prevent the formation of pinholes or gaps in the bag-like exterior body. .

[Brief explanation of drawings]

Fig. 1 is a partial sectional view of a sealed lead-acid battery using a conventional bag-like exterior body, Fig. 2 is a perspective view of a lattice body in an embodiment of the present invention, and Fig. 3 is an embodiment of the present invention. FIG. 2 is a partial cross-sectional view of a sealed lead-acid battery using a bag-like exterior body in FIG. DESCRIPTION OF SYMBOLS 1...Film-like synthetic resin, 2...Exterior body, 4...Positive electrode plate, 5...Negative electrode plate, 8
・・・・・・Lattice, 8b1-9 tenoku, 8C...
9 are. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] An electrode plate group consisting of a positive electrode plate, a negative electrode plate, and a separator is sandwiched between two film-like or sheet-like synthetic resin bodies that are acid-resistant and heat-weldable, and the synthetic resin body surrounding the electrode plate group is one piece. A sealed lead-acid battery with an unwelded part formed in some places and heat welded in other parts to form an exterior body, characterized by rounded or tapered corner parts of the lead alloy grid of the electrode plate. lead-acid battery.