JPS61232561A - Button type alkaline battery - Google Patents

Abstract

PURPOSE:To increase storage life and productivity by blanking a horizontal central part of a positive supporting ring having opposite L-shaped cross section from a negative electrode direction, and fixing burr or sharp edge produced by blanking to a positive electrode. CONSTITUTION:The contact part of the edge a of a positive supporting ring and a positive mix 1 is pressed so as to form a circular groove from the direction of negative electrode 5 to the direction of positive electrode to prevent the contact of burr or sharp edge of the positive supporting ring with a separator. Since the ring 3 is pressed so as to form a circular groove against the positive mix, molding ability of the positive electrode is improved. When this positive electrode is used for a button type alkaline battery, damage of the separator 4 is prevented and storage life is increased since the central blanking part, which is in contact with separator 4, of the supporting ring 3 is pressed so as to form a circular groove against the positive mix. Productivity is also increased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in button batteries using alkaline electrolytes.

The general structure of a conventional button-type alkaline battery will be explained with reference to FIG. 2 for a silver oxide battery.

1 in the figure is a positive electrode mixture made of silver oxide powder, phosphorous graphite as a conductivity imparting agent, and manganese dioxide to improve moldability. Positive electrode case 2 is made of iron plated with nickel.
It is filled and molded inside.

3 is a positive electrode pedestal made of nickel-plated iron or iron alloy; 4 is a microporous film made of polyethylene, etc., a separator layer made of cellophane, and a liquid-containing layer made of nylon nonwoven fabric, etc.; 6 is a negative electrode; It is composed of zinc chloride powder, a thickening agent such as carboxymethyl cellulose, and an alkaline electrolyte. 6 is a gasket made of nylon, and 7 is a negative electrode sealing plate. In the silver oxide battery having the above configuration, the positive electrode pedestal indicated by 3 uniformly receives the pressure applied to the positive electrode part when the battery is sealed and caulked, thereby preventing the positive electrode part from collapsing. It has important functions such as preventing deterioration when pressed against the positive electrode mixture 1 and preventing internal short circuits.

However, as shown in FIG. 3, in the conventionally used positive electrode pedestal 3, the center punched part is punched from the positive electrode toward the negative electrode, and burrs appear on part a, which is the edge of the opening.
Even if it does not reach IJ-1, it has a very sharp blade shape.

Problems to be Solved by the Invention However, after the battery is assembled, part a of the edge of the pedestal comes into contact with the separator layer 4 in Figure 2, damaging the separator and causing a decrease in the storage performance of the battery. .

Therefore, in the past, in order to solve this phenomenon, methods were proposed in which the central punched part of the positive electrode pedestal was punched out from the negative electrode toward the positive electrode, so that the burrs did not protrude toward the separator side, but toward the positive electrode side, and A positive electrode pedestal was used in which a punched portion was punched from the positive electrode toward the negative electrode, and the burrs or sharp cross-sections generated by the punching were pressed to give a rounded shape.

However, in these methods, during the process of fixing and crimping the positive electrode mixture 1 and the positive electrode pedestal 3 to the positive electrode case 2, the positive electrode part may crack due to burrs appearing on the positive electrode side, and the positive electrode part may not be configured in a normal state. It was difficult.

Furthermore, as the positive electrode pedestal 3 becomes thinner and smaller in size, it becomes difficult to uniformly press burrs or sharp cross-sections caused by punching, making it unsuitable for practical use.

The present invention solves the above-mentioned problems, and aims to eliminate damage to the separator due to burrs on the positive electrode pedestal and provide a stable positive electrode section.

Means to Solve the Problems The present invention fixes and presses the positive electrode mixture and the positive electrode pedestal to the positive electrode case, and eliminates burrs or sharp cross-sections generated from the positive electrode toward the negative electrode in the horizontal central punched part of the positive electrode pedestal. The tip is fixed and crimped to the annular groove.

Function If the burr or cross-sectional tip is fixed and crimped in the shape of an annular groove in this way, the positive electrode mixture will not be damaged, the positive electrode will have excellent moldability, and the connection between the central punched part of the positive electrode pedestal and the separator layer will be excellent. It is possible to prevent damage to the separator by preventing direct contact, and to provide a button-shaped battery with excellent storage reliability.

Example Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 1 shows an embodiment of the present invention, in which the burr or cross-sectional tip of the positive electrode pedestal is fixed and crimped into an annular groove shape. To explain this, the contact point between the mouth edge a and the positive electrode mixture 1 is pressed from the negative electrode direction toward the positive electrode part in an annular groove shape, and the burrs and sharp blade-like ends that have occurred at the tip of the cross section are removed. This prevents it from coming into contact with the separator. In addition, since pressure is applied to the annular groove at the same time as crimping, the moldability of the positive electrode is also excellent.

When a positive electrode part having the above shape is used in a button-type alkaline battery, for example, a silver oxide battery shown in Fig. 2, the central punched part of the positive electrode pedestal in the part that contacts the separator is shaped like an annular groove. Furthermore, there is no risk of damaging the separator layer, and a battery with excellent storage reliability can be obtained.

A silver oxide battery 5kt44 was made using the positive electrode part of the present invention, and the size of the shape *1 between this and the conventional product of the same shape shown in Fig. 2 was measured after fixing and crimping in the annular groove shape. be. In addition, *2 storage capacity remaining rate (the number of discharged units is 1 each)
0 pieces), the discharge resistance 15 is Ω, the discharge time immediately after manufacture is 1oo% for the discharge time up to the final voltage 1.4V,
On the other hand, the discharge time after each storage day is expressed as a percentage. Furthermore, in the case of the molded product fixed and crimped in a Larrat shape used as the conventional product mentioned above, there is always a risk that the separator may be cut due to the pressure during battery construction during mass production. Furthermore, as the thickness becomes thinner, the moldability deteriorates. However, in the present invention, these problems can be solved because the burrs and sharp blade-like ends are fixed and crimped in the annular groove shape.

As described above, the button 9 alkaline battery according to the present invention has excellent storage reliability and is suitable for mass production.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view showing an example of a positive electrode molding part used in the button-type alkaline battery of the present invention, Figure 2 is a cross-sectional view of a silver oxide battery using a positive electrode pedestal, and Figure 3 is a cross-sectional view of a conventional positive electrode molding part. FIG. 1... Positive electrode mixture, 2... Positive electrode case,
3... Positive electrode pedestal, a... Mouth rim. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure I Figure 3

Claims (1)

[Claims] The horizontal central punching part of the positive electrode pedestal with an inverted L-shaped cross section is punched out from the positive electrode toward the negative electrode, and the burr or sharp cross-sectional tip produced by this punching is pressed against the positive electrode to form an annular groove. A button-shaped alkaline battery characterized by being fixed and crimped in a shape.