JPS6337461B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a dry battery, in which asphalt or a mixture thereof is injected as an internal sealing filler into a zinc can filled with a power generation element through a flange paper.
The purpose of this invention is to improve the sealing method for dry batteries that are sealed with synthetic resin sealing lids with molded anode terminal caps, thereby preventing the sealing portion from bursting due to an increase in internal pressure of the battery. The sealing and exterior structure of a conventional small dry battery is as shown in Fig. 4, in which a cathode zinc can 1 filled with power generating elements such as an anode mixture, carbon rods, and an isolation layer is filled with asphalt or a mixture thereof as an internal sealing filler 2. Inject through the flange paper 3 and anode terminal cap 4
A molded synthetic resin sealing lid 5 was attached to the upper side of the zinc can 1 to seal it, and the outer periphery of the zinc can 1 was covered with an exterior resin tube 6. In this structure, the internal sealing filler 2 is provided to prevent moisture from escaping from the mixture and the isolation layer, and the internal sealing filler 2 and the flange supporting it are provided to improve the sealing effect. Because Paper 3 was not designed to vent gas, accidents often occurred in which the sealing part burst due to the rapidly increasing gas pressure inside the battery during abnormal discharges such as short circuits or reverse connection discharges. . In order to solve these problems, attempts have been made in the past to eliminate the internal sealing filler and seal the seal with only a resin sealing lid, but in that case, it was not possible to sufficiently prevent moisture from escaping, and the battery However, due to the voltage and current deterioration due to internal drying, it has not yet been implemented. The dry battery manufacturing method of the present invention largely eliminates the above-mentioned drawbacks, and one embodiment thereof will be described below with reference to the drawings. Reference numeral 1 in FIG. 1 is a zinc can filled with a power generation element, and an internal sealing filler 2 is injected through a flange paper 3 as in the conventional example. A filler 2' is also applied to the upper peripheral surface of the carbon rod 7 as shown in FIG. As shown in Fig. 3, the inner surface of the synthetic resin sealing lid 5 on which the anode terminal cap 4 is molded has a gas vent cutout for removing gas, etc., which increases rapidly in the battery during abnormal discharge such as short circuit or reverse connection discharge. 8 is provided in a part of the carbon rod through hole 9, and this degassing notch 8 opens on the lower surface of the sealing lid 5, and its inner end is connected to the tip of the flange 10 of the resin-molded anode terminal cap 4. has reached. To seal the dry battery, asphalt or its mixture as the internal sealing filler 2 is injected into the zinc can 1 through the flange paper 3, and asphalt or its mixture is also injected into the upper circumferential surface of the carbon rod 7 as the internal sealing filler 2'. The mixture is applied in an annular shape, and then the anode terminal cap 4 molded on the resin sealing lid 5 is fitted onto the upper end of the carbon rod 7. At this time, a part of the internal sealing filler 2' applied annularly to the upper circumferential surface of the carbon rod 7 is removed from a degassing notch 8 provided in a part of the carbon rod through hole 9 of the resin sealing lid. Fill in the zinc can 1
It is meant to seal. In a dry cell manufactured by the method described above, the gas pressure inside the battery increases when an abnormal discharge such as a short circuit or a reverse connection discharge occurs. It is pushed up into the gas venting notch 8 provided in the anode terminal cap 5, and is pushed out around the tip of the flange paper 10 of the anode terminal cap 4, thereby lowering the pressure inside the battery. This resin sealing lid 5
The degassing notch 8 provided on the inner surface of the gas vent 8 is normally completely filled with asphalt or a mixture thereof as the internal sealing filler 2', thereby maintaining the sealing effect completely. As described above, the present invention eliminates accidents such as rupture of the sealing part due to an increase in gas pressure inside the battery that occurs during abnormal discharge such as short circuit or reverse connection discharge, and also maintains the sealing effect under normal conditions. This ensures storage performance. The effects will be explained below in comparison with the conventional example. A is a UM-4 type dry cell manufactured by the manufacturing method of the present invention, and B is a conventional UM with the structure shown in Figure 4.
-It is a type 4 dry battery. (1) Rupture test of the sealing part (15Ω load continuous discharge, 1 out of 4 connected in reverse, situation 2 hours after discharge)

[Table] Storage performance test (Batteries immediately after manufacture and after storage at room temperature for 12 months are intermittently discharged at a rate of 10 minutes/day under a 15Ω load, and the average cumulative discharge duration until the final voltage reaches 0.85V ( (X ) and variation (R), and the number of sample batteries was 70 in each case.)

【table】 [Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of a dry battery manufactured in an example of the present invention, FIG. 2 is a partial cross-sectional view of the opening of a zinc can sealed with an internal sealing filler, and FIG.
The figure is a bottom view of a synthetic resin sealing lid in which an anode terminal cap is molded, and FIG. 4 is a partially cutaway side view of a conventional dry battery. 1... Zinc can filled with power generation elements, 2, 2'...
... Internal sealing filler, 3 ... Flange paper, 4 ... Anode terminal cap, 5 ... Synthetic resin sealing lid, 7 ... Carbon rod, 8 ... Gas venting notch, 9 ... Carbon rod through hole , 10... Cap's rim.

Claims (1)

[Claims] 1. Into a zinc can filled with power generation elements such as anode mixture, carbon rods, and isolation layers, asphalt or its mixture is injected as an internal sealing filler through flange paper, and the upper part of the carbon rod protrudes above the mixture. A synthetic resin sealing lid with a molded anode terminal cap that fits onto the carbon rod is attached to the carbon rod. A method for manufacturing a dry battery, comprising: providing a gas venting notch that opens and reaches the terminal cap; and sealing the gas venting notch with asphalt or a mixture thereof applied to the upper peripheral surface of the carbon rod.