JPS6038826B2 - Alkaline battery manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the improvement of alkaline batteries such as silver batteries, mercury batteries, nickel cadmium batteries, and alkaline manganese batteries, and its purpose is to improve leakage resistance.

Advantageously, the gasket that seals the opening of the battery container and the surface of the sealing plate are filled with a sealing agent such as polyamide resin, polyethylene resin, asphalt pitch, etc. to prevent leakage of the electrolyte from the above-mentioned surface. Various things have been proposed, but
When applying the sealant to the gasket and/or sealing board, the sealant may not fully penetrate into the minute recesses on the surface, or the surface of the sealant layer may become uneven due to uneven application or pinholes. The effect of the sealant may not be fully demonstrated and leakage may occur from the contact surface between the gasket and the sealing plate.

This invention eliminates the above-mentioned drawbacks, and embodiments thereof will be described below with reference to the drawings.

As shown in FIG. 1A, a folded hanging part 2 is provided around the periphery of a metal sealing plate 1 that also serves as a cathode terminal, and the outer surface of the hanging part 2 is made of fatty polyamide, polyethylene, etc. A sealant solution made of a thermoplastic resin such as asphalt pitch is applied and dried to form a sealant layer 3.

On the other hand, the gasket 4 has an L-shaped cross section, as shown in FIG. It is made of elastic synthetic resin such as polyamide resin, polypropylene resin, or polyethylene resin.

The inner cover b of the rising portion 5 is designed to be slightly smaller than the outer cover a of the sealing plate 1, and when the gasket 4 is placed sideways on the sealing plate 1, the rising portion 5 of the gasket 4 is pushed outward and expanded. The sealant layer 3 is pressed over the entire surface by the anti-rolling force. Next, as shown in FIG. 2, when the central part of the sealing plate 1 is held between the heating jig 7 from above and below and heated, the heat is transmitted through the sealing plate 1 and softens the sealant layer 3, and the gasket 4
The sealant softened by the pressure is pushed into the fine recesses formed on the surface of the sealing plate 1 and gasket 4 and adheres well, and even if the sealant layer 3 has uneven coating or pinholes, By being softened by heating and being pressed by the gasket 4, it forms a uniform thin layer and comes into liquid-tight contact with the gasket 4.

FIG. 3 shows a button-type alkaline battery using the assembly of the sealing plate 1 and gasket 4 made in this way, in which silver oxide, mercury oxide, manganese dioxide, etc. Main body: anode 9, separator 10, absorbent paper 1
1 are inserted one after another, and the sealing plate 1 and gasket 4 filled with the cathode agent 12 made of a mixture of zinc powder and gelled alkaline electrolyte are iron-bonded into the opening of the anode can 8. Curl the closed end inward to seal the battery. A button-type alkaline battery A according to this example and a subordinate alkaline IJ battery B of the same type with a sealant layer applied and formed were 45oo and 20
The following table shows the rate of leakage when left for several days. This invention has the above-mentioned structure, and the softening of the sealant layer due to heating and the pressing of the gasket work together to modify the film state of the sealant layer and tightly adhere to the sealing plate and the gasket. As is clear from the above table, excellent leakage resistance can be obtained.

Among sealants, fatty polyamide resins in particular have functional groups such as amine groups and carboxyl groups in their molecular structure, so they have good adhesion to metals such as sealing plates, and are therefore useful.

Brief Description of the Drawings Figures 1A and B are sectional views of the sealing plate and gasket used in this invention, Figure 2 is a sectional view showing the state of manufacture of this invention, and Figure 3 is a button-type alkaline battery according to this invention. FIG.

1...Sealing board, 3...Sealant layer, 4...Gasket"
a...Inner diameter, b...Outer diameter.

Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. The inner diameter b of the gasket 4 is designed to be slightly smaller than the outer diameter a of the sealing plate 1, and the inner surface of the gasket 4 that contacts the sealing plate 1 and/or the peripheral part of the sealing plate 1 that contacts the gasket 4 is made of thermoplastic material. After forming the sealant layer 3 made of resin and fitting the gasket 4 to the peripheral part of the sealing plate 1,
The sealing plate 1 is heated from the outside to soften the sealant layer 3, and the elasticity of the gasket 4 is used to modify the film condition of the sealant layer 3, so that the sealant layer 3 is able to seal the gap between the gasket 4 and the sealing plate 1. A method for producing an alkaline battery characterized by having a closed contact surface.