JPH0917408A - Alkaline dry battery - Google Patents

Abstract

PURPOSE: To improve shock resistance, and increase the effective volume of a gel negative electrode by providing insulation bottom paper having a stepped shape along the inside bottom face of a positive electrode can. CONSTITUTION: The shape of an insulation bottom plate isolating a positive electrode can 3 and a gel negative electrode 6 is the stepped shape along the inside bottom face of the positive electrode can 3. Thereby, against a shock by a continuous vibration and a strong shock by dropping down when an alkaline dry battery is transported or carried, even if the gel negative electrode 6 moves inside the alkaline dry battery, insulation bottom paper is fitted to two steps, the recessed portion of the inside bottom face of the positive electrode can 3 and the inside wall face of a separator 5, so as not to move. Accordingly, the isolation between the positive electrode can 3 and the gel negative electrode 6 is maintained so that no inside short occurs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkaline dry battery having improved impact reliability and increased effective volume of a reaction active material.

[0002]

2. Description of the Related Art Alkaline dry batteries are superior in continuous discharge and high load discharge characteristics as compared with manganese dry batteries using zinc chloride electrolyte. Therefore, it has been used as a power source for recording / playback devices and flashlights for cameras that have been heavily loaded, and with the increasing performance of today's electrical equipment, the proportion of alkaline batteries in dry batteries has increased year by year. It is desired to further improve the performance of alkaline dry batteries.

A conventional alkaline dry battery will be described below. FIG. 5 shows the structure of a conventional alkaline dry battery. In FIG. 5, 11 is a flat plate-shaped insulating bottom paper. Reference numeral 2 is an outer label, 3 is a positive electrode can, 4 is a positive electrode mixture, 5 is a separator, 6 is a gelled negative electrode, 7 is a current collector, 8 is a resin sealing body, 9 is an insulating washer, and 10 is a bottom plate.

Here, the insulating bottom paper 11 separates the positive electrode can 3 and the gelled negative electrode 6 from each other. If the separation is incomplete, the positive electrode can 3 and the gelled negative electrode 6 come into contact with each other, that is, a short circuit occurs. , The battery is defective.

[0005]

Since the conventional insulating bottom paper has a flat shape, the alkaline dry battery is resistant to the shock caused by continuous vibration when carrying or carrying the alkaline dry battery and the strong shock caused by dropping. As the gelled negative electrode moves inside, the insulating bottom paper also easily moves, and there is a risk that the positive electrode can comes into contact with the gelled negative electrode, that is, an internal short circuit occurs due to the movement.

In order to prevent the internal short circuit due to the movement of the insulating bottom paper, a means for bending the lower end of the separator 5 as shown in FIG. 6 is used, but it is not sufficient as a means for suppressing the movement of the insulating bottom paper. Also, this means has a drawback that the effective volume of the gelled negative electrode is reduced by the amount corresponding to the bending of the separator.

In addition, as a means for preventing the above-mentioned internal short circuit, a means for injecting a heat-fusible substance into the lower end of the separator instead of the insulating bottom paper (Japanese Patent Laid-Open No. 58-154177) has been implemented. Although an internal short circuit does not occur, there is a problem that the manufacturing process becomes complicated and the cost increases.

The present invention solves the above problems,
An object of the present invention is to provide an alkaline dry battery in which reliability against impact is improved, that is, movement of an insulating bottom paper due to impact is suppressed and an effective volume of a reaction active material is improved.

[0009]

To achieve this object, the alkaline dry battery of the present invention comprises a stepped bottomed cylindrical positive electrode can also serving as a positive electrode terminal, and a hollow cylindrical cylindrical can arranged in the positive electrode can. A positive electrode mixture and a gelled negative electrode filled in the hollow part of the positive electrode mixture through a tubular separator, and the lower end opening of the tubular separator is closed with a bottom paper to form the positive electrode can and gel. An alkaline dry battery in which the cathode and the cathode are isolated from each other is characterized in that the bottom paper has a stepped shape along the shape of the inner bottom surface of the cathode can.

The bottom paper having a planar shape is inserted into a battery by using an insertion punch having a convex portion along the shape of the inner bottom surface of the positive electrode can, and the bottom paper having the planar shape is inserted into the positive electrode can. It may be formed by pressing against the inner bottom surface of.

[0011]

In the alkaline dry battery of the present invention, the shape of the insulating bottom plate that separates the positive electrode can from the gelled negative electrode is stepped along the shape of the inner bottom surface of the positive electrode can so that the alkaline dry battery is transported or carried. Even if the gelled negative electrode moves inside the alkaline dry battery against the impact of continuous vibration when dropping, or the strong impact of dropping, the insulating bottom paper will not separate the concave part of the inner bottom surface of the positive electrode can from the inner wall surface of the separator. Since they are assembled in two stages, they do not move, the separation between the positive electrode can and the gelled negative electrode is maintained, and no internal short circuit occurs.

Further, by forming the insulating bottom paper into a stepped shape that follows the shape of the inner bottom surface of the positive electrode can, the effective volume of the gelled negative electrode can be increased as compared with the conventional planar shape.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of an alkaline dry battery using an insulating bottom paper having a stepped shape according to the present invention.

In FIG. 1, reference numeral 1 is an insulating bottom paper having a stepped shape. 2 is an outer label, 3 is a positive electrode can, 4 is a positive electrode mixture, 5 is a separator, 6 is a gelled negative electrode, 7 is a current collector,
Reference numeral 8 is a resin sealing body, 9 is an insulating washer, and 10 is a bottom plate. The insulating bottom paper 1 has a stepped shape along the shape of the inner bottom surface of the positive electrode can 3.

In producing the alkaline dry battery of the present invention, it was produced by the following two methods. That is, an insulating bottom sheet having a stepped shape before the battery construction (FIG. 2A and FIG. 2B is used (this is Example 1)) and a planar shape similar to the conventional product before the battery construction. Use an insulating bottom paper (FIGS. 3 (a) and 3 (b)) with a convex insertion punch 12 (FIG. 4) along the shape of the inner bottom surface of the positive electrode can when inserting it into the battery. Then, the one manufactured as shown in FIG. 1 (Example 2) was manufactured.

The results of impact resistance characteristics of the alkaline dry batteries of the above two examples and the conventional alkaline dry battery having the planar bottom paper are shown in Table 1 below.

[0018]

[Table 1]

Here, the impact resistance means that the + electrode of an alkaline dry battery is placed on the upper side and a vibration of 60 times per minute is performed for 50 m.
This is a test for determining the presence or absence of an internal short circuit by measuring the voltage after applying an amplitude of m for 1 hour and varying the voltage measured value before and after applying the vibration.

As can be seen from this (Table 1), in the conventional alkaline dry battery having the planar insulating bottom paper, an internal short circuit occurs, whereas in the stepped shapes according to Examples 1 and 2, In the alkaline dry battery provided with the insulating bottom paper, the excellent effect is obtained in the impact resistance property.

[0021]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, by providing an insulating bottom paper having a stepped shape corresponding to the shape of the inner bottom surface of the positive electrode can, the impact resistance can be improved and the gelled negative electrode can be obtained. It is possible to realize an excellent alkaline dry battery capable of increasing the effective volume of

[Brief description of the drawings]

FIG. 1 is a side sectional view of an alkaline dry battery of the present invention.

FIG. 2 (a) is a top view of the stepped insulating bottom sheet of the present invention. (B) is a side view of the stepped insulating bottom sheet of the present invention.

FIG. 3A is a top view of a planar insulating bottom paper, and FIG. 3B is a side view of a planar insulating bottom paper.

FIG. 4 is a side view of an insulating bottom sheet insertion punch used in Example 2;

FIG. 5 is a side sectional view of a conventional cylindrical alkaline battery LR6.

FIG. 6 is a cross-sectional view near the positive electrode terminal of an alkaline dry battery LR6 in which a conventional separator is bent.

[Explanation of symbols]

 1 Stepped Insulating Bottom Paper 2 Label Exterior 3 Positive Electrode Can 4 Positive Electrode Mixture 5 Separator 6 Gel Negative Electrode 7 Current Collector 8 Resin Sealing Body 9 Insulating Washer 10 Bottom Plate 11 Planar Insulating Bottom Paper 12 Insert Punch

Claims (2)

[Claims] 1. A positive electrode can having a bottomed cylindrical positive electrode can, which also serves as a positive electrode terminal, a hollow cylindrical positive electrode mixture arranged in the positive electrode can, and a hollow of the positive electrode mixture through a cylindrical separator. In the alkaline dry battery, the bottom end of the tubular separator is closed with a bottom paper to separate the positive electrode can from the gel negative electrode. An alkaline dry battery having a stepped shape that conforms to the shape of the inner bottom surface of the. 2. The bottom paper having a planar shape is inserted into a battery by using an insertion punch having a convex portion along the shape of the inner bottom surface of the positive electrode can, and the bottom paper having the planar shape is removed. The alkaline dry battery according to claim 1, which is formed by being pressed against the inner bottom surface of the positive electrode can.