JPH0955212A - Alkaline battery and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alkaline battery with high capacity by improving the shape of a positive mix in the opening part of a battery can. SOLUTION: An alkaline battery has a battery can 1 of a cylinder shape with bottom, a cylindrical positive mix 2 arranged on the inside of the battery can 1 through a separator 4, a cylindrical negative mix 3, a sealing member 10 for sealing the opening part 7 at one end of the battery can 1, and a current collector pin 5 inserted into a through hole 11 of the sealing member 10. The shape of the positive mix 2 in the opening part 7 of the battery can 1 is formed so as to have a differential step cross section along the sealing member 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkaline battery used as a power source for portable electronic devices, cordless electronic devices and the like, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, there have been remarkable improvements in the performance and miniaturization of electronic devices such as video cameras and headphone stereos, and the demand for higher capacity batteries for powering such electronic devices has also increased. There is. Manganese dry batteries have been conventionally used as batteries for such applications.
Alkaline batteries using an alkaline electrolyte such as potassium hydroxide have come to be widely used to obtain a larger capacity.

By the way, since this alkaline battery uses a strong alkaline solution as an electrolytic solution which may affect human skin, eyes, etc., it is generally sealed so that the alkaline electrolytic solution does not leak out. There is. For example, a sealing member made of nylon, polypropylene or the like is fitted into an opening of a metal battery can body to seal the opening.

A safety device such as a safety valve for preventing the battery from bursting, and a cushion portion are provided at the center of the opening member so that the sealing member is not largely deformed when the opening portion of the battery can body is caulked. It is provided. Since the reinforcing member is located under the sealing member, the sealing member is generally convex toward the inside of the battery can body.

FIG. 6 shows a cross-sectional view of a constitutional example of a conventional alkaline battery. The alkaline battery shown in FIG. 6 has a bottomed cylindrical battery can body 41 made of a nickel-plated iron plate, and the outer periphery of the battery can body 41 is the inside of the battery can body 4.
1, a cylindrical positive electrode mixture 42 made of manganese dioxide and graphite is provided, and the cylindrical positive electrode mixture 42 is separated by a separator 44 made of a non-woven fabric to form granular zinc and an aqueous potassium hydroxide solution. A gelled negative electrode mixture 43 composed of a thickener or the like is placed.

In this case, the opening side of the positive electrode mixture 42 of the battery can body 41 is formed flat at a position where its end surface is in contact with the tip of the sealing member 46 described later.

The opening 50 at one end of the battery can body 41 is
A sealing member 46 made of, for example, polypropylene for sealing the opening 50, a reinforcing member 47 made of nickel-plated iron, a spring 48, and a cover 49 made of nickel-plated iron serving as a negative electrode terminal are assembled in this order and covered. The outer peripheral end of the cover 49 is attached to the battery can body 4.
1 is attached so as to hold the sealing member 46 via the gasket portion 46d.

A through hole 46a is formed in the center of the sealing member 46, and a nail-shaped current collecting pin 45 made of brass is press-fitted into the through hole 46a.
Is inserted into the negative electrode mixture 43 as a negative electrode current collector. In this case, the head of the collector pin 45 is attached to the spring 48.
Then, the spring 48 is elastically pressed into contact with the negative electrode terminal which is the cover 49 so as to be electrically connected.

When sealing the opening 50 of the battery can body 41, the diameter of the end of the opening 50 of the battery can body 41 is reduced and caulked.

In this case, the sealing member made of polypropylene is provided with a safety valve 46b for preventing the battery from bursting at the central portion thereof, and when the opening 50 of the battery can body 41 is caulked, the sealing member becomes large. A cushion portion 46c is provided so as not to be deformed.

[0011]

By the way, in order to increase the capacity of the alkaline battery as described above, it is necessary to fill a larger amount of the positive electrode mixture and the negative electrode mixture. Among them, since the sealing member 46 occupies a relatively large volume, it is difficult to achieve a higher capacity than the current one.

In view of this point, the present invention has an object to further increase the capacity of the alkaline battery as described above.

[0013]

The alkaline battery of the present invention comprises a cylindrical battery can body having a bottom, a positive electrode mixture arranged in a cylindrical shape on the outer peripheral side of the battery can body, and the cylindrical positive electrode. Alkaline battery having a negative electrode mixture arranged via a separator in the mixture, a sealing member for sealing the opening at one end of the battery can body, and a collector pin press-fitted into the through hole of the sealing member In the above, the shape of the opening of the positive electrode mixture is a stepped cross section along the sealing member.

Further, in the method for producing an alkaline battery of the present invention, a battery can body having a bottomed cylindrical shape is filled with a predetermined amount of the positive electrode material mixture, and thereafter, a hollow cylindrical upper punch having a convex tip is used for this battery. Set it in the can, then through the hole in the center of this upper punch,
The inner punch is pushed to a predetermined position of the battery can body, and the shape of the positive electrode mixture is a hollow cylindrical shape having a stepped cross section at the opening of the battery can body.

According to the present invention, since the opening of the positive electrode mixture in the battery can has a stepped cross section along the sealing member, a larger amount of the positive electrode mixture can be filled. Higher capacity can be achieved.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the alkaline battery of the present invention and its manufacturing method will be described below with reference to the drawings. FIG. 1 shows a cross-sectional view of a configuration example of an alkaline battery according to this example.
The alkaline battery according to the present embodiment has a bottomed cylindrical battery can body 1 made of a nickel-plated plate, and the inside of the battery can body 1 contacts the battery can body 1 on the outer peripheral side thereof to form manganese dioxide. Cylindrical positive electrode mixture 2 composed of graphite
A cylindrical negative electrode mixture 2 is separated by a separator 4 made of a nonwoven fabric, and a gelled negative electrode mixture 3 made of granular zinc, an aqueous solution of potassium hydroxide, a thickener and the like is placed.

The shape of the opening 7 of the battery can body 1 of the positive electrode mixture 2 is a stepped shape in cross section along a sealing member 10 described later.

An example of the above manufacturing method will be described with reference to FIGS. First, as shown in FIG. 2, 85 parts by mass of manganese dioxide, 8 parts by mass of graphite, and 7 parts by mass of 38% potassium hydroxide aqueous solution were mixed to prepare a positive electrode mixture, and a predetermined amount of this positive electrode mixture was mixed with this battery. Fill the can body 1.

Next, as shown in FIG. 3, a hollow cylindrical upper punch 30 having a convex tip (stepped cross section) is set in the opening 7 of the battery can 1. In this case, this upper punch 30
The outer diameter "a" of the tip end portion is, for example, 10.5 mm, the outer diameter "b" of the body portion is, for example, 13.2 mm, the height c of the convex portion (step portion) is, for example, 3 mm, and the central hole diameter d is, for example, 9. 02
mm. The tip of the upper punch 30 is set at a position, for example, 40 mm from the bottom of the battery can body 1.

Next, as shown in FIG. 4, a cylindrical middle punch 31 having an outer diameter of, for example, 9 mm was pushed through the central hole of the upper punch 30 to a position of, for example, 1.5 mm from the bottom of the battery can body 1. . In this case, this mixture is pushed up toward the opening 7 side of the battery can body 1 by the middle punch 31 and hits the upper punch 30 to change the shape of this opening of the positive electrode mixture 2 to this upper punch 30. The cross-section has a step shape.

Next, the upper punch 30 and the middle punch 31 are removed. At this time, the shape of the positive electrode mixture 2 in the battery can body 1 becomes a hollow cylindrical shape having a stepped cross section at the opening 7 of the battery can body 1, as shown in FIG.

The hollow cylindrical positive electrode mixture 2 is separated by a separator 4 made of a non-woven fabric so as to contain a gelled negative electrode mixture 3 made of granular zinc, an aqueous potassium hydroxide solution, a thickener and the like.

Next, the opening 7 of the battery can 1 is closed with the sealing member 10.
So that it will be sealed. The sealing member 10 is made of a plastic material such as nylon or polypropylene.

The sealing member 10 is formed around the through hole 11 formed in the center of the cylindrical portion 12 and around the cylindrical portion 12, and a sealing portion 15 for blocking the inside and the outside of the battery can body 1.
And a safety valve portion 18 in which a part of the seal portion 15 is thinned, and a cushion portion 1 for preventing a large deformation when caulking the opening 7 of the battery can body 1.
7 and a gasket portion 14 that comes into contact with the inner peripheral surface of the metal battery can body 1.

The cushion portion 17 is located on the bottom side from the opening 7 side of the battery can 1, and the sealing member 10 is integrally formed in a convex shape as a whole from the opening 7 toward the bottom side. It is a thing. In this case, the height of the cushion portion 17 is, for example, 3.5 mm, the diameter of the cushion portion 17 is, for example, 10.2 mm, and the outer diameter when the opening 7 of the battery can body 1 of the sealing member 10 is caulked and sealed. For example, it is set to 13.3 mm.

Further, a reinforcing member 20 for reinforcing the sealing member 10 is installed, and further, a metal spring 9 and a disk-shaped iron forming a negative electrode terminal for covering the reinforcing member 20 are plated with nickel, for example. The metal cover 6 is attached.

The reinforcing member 20 is made of a metal plate having higher strength than the sealing member 10, for example, an iron plate plated with nickel. Further, a nail-shaped negative electrode current collecting pin 5 made of, for example, brass is press-fitted into the through hole 11 of the sealing member 10 into which the reinforcing member 20 is fitted, and the current collecting pin 5 is inserted into the negative electrode mixture 3 and the current collecting pin 5 is inserted. The head 5a of the electricity pin 5 is pressed by a metal spring 9 so that the electricity collection pin 5 is electrically connected to the spring 9 and the negative electrode terminal 6.

In this case, the shape of the opening 7 of the battery can body 1 of the positive electrode mixture 2 is a stepped shape in cross section along the sealing member 10. That is, the inner diameter of the hollow cylindrical central portion 2a of the positive electrode mixture 2 is, for example, 9 mm, the inner diameter of the tip portion 2b of the battery can 1 on the opening 7 side is, for example, 10.5 mm, and the outer diameter is, for example, 1 mm.
The height of the outer peripheral portion of the positive electrode mixture 2 was, for example, 43 mm, and the height of the inner peripheral portion thereof was, for example, 40 mm. The mass of the positive electrode mixture 2 in this example was 10.5 g, for example.

Further, in FIG. 1, 13 is the battery can body 1.
Is a positive electrode terminal made of a metal such as an iron plate plated with nickel on the outside of the bottom of the battery can body 1, and a predetermined portion of the outer periphery of the battery can body 1 is covered with an outer label 8 such as a synthetic resin.
To cover.

According to this embodiment, the shape of the opening 7 of the battery can body 1 of the positive electrode mixture 2 in the battery can body 1 has a stepped cross section along the sealing member 10. There is an advantage that a larger amount can be filled and a higher capacity can be achieved.

Incidentally, although the mass of the positive electrode mixture 2 was 10.5 g in the above-mentioned embodiment, the battery can body 41 having the same size as that in the above-mentioned embodiment is used and the similar sealing member 46 is used.
When a conventional structure as shown in FIG. 6 was used, the mass of the positive electrode mixture 42 was 10 g.

Further, the alkaline battery of the present example and the alkaline battery of the conventional example were continuously discharged under a load of 10Ω,
When the time until the battery voltage reached 1.0 V was measured, the alkaline battery of this example had a discharge time of 16.0 hours, and the alkaline battery of the above-mentioned conventional example had a discharge time of 15.3 hours.

In the above-mentioned FIGS. 2 to 5, the upper punch 30 was set and then the middle punch 31 was pushed in. Instead of this, the battery can body 1 was filled with a predetermined amount of the positive electrode mixture 2, and then the middle punch 31 was pressed. The punch 31 is inserted into the battery can body 1 to a predetermined position and set, and then the hollow cylindrical upper punch 30 having a convex tip through the central hole is inserted into the battery can body 1. Of course, the positive electrode mixture 2 may be pushed into a hollow cylindrical shape having a stepped cross section at the opening of the battery can 1.

Further, in the above-mentioned embodiment, the example in which the positive electrode mixture is directly filled in the battery can body 1 as shown in FIG. 2 has been described. The battery can body 1 may be filled.

The present invention is not limited to the above embodiment,
It goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0036]

EFFECTS OF THE INVENTION According to the present invention, it is possible to easily obtain a positive electrode mixture having a hollow cylindrical shape having a stepped cross section at the opening of the battery can body.

Further, according to the present invention, since the shape of the opening of the battery can body of this positive electrode mixture has a stepped shape in cross section along the sealing member, it is possible to fill a larger amount of the positive electrode mixture. There is an advantage that the capacity can be increased.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the alkaline battery of the present invention.

FIG. 2 is a cross-sectional view showing the steps of an embodiment of the method for manufacturing an alkaline battery of the present invention.

FIG. 3 is a cross-sectional view showing the steps of an embodiment of the method for manufacturing an alkaline battery of the present invention.

FIG. 4 is a cross-sectional view showing the steps of an embodiment of the method for manufacturing an alkaline battery of the present invention.

FIG. 5 is a cross-sectional view showing the steps of one embodiment of the method for manufacturing an alkaline battery of the present invention.

FIG. 6 is a cross-sectional view showing an example of a conventional alkaline battery.

[Explanation of symbols]

 1 Battery Can 2 Positive Electrode Mixture 3 Negative Electrode Mixture 4 Separator 5 Collector Pin 6 Negative Electrode Terminal (Metal Cover) 7 Opening 8 Exterior Label 9 Spring 10 Sealing Member 11 Through Hole 13 Positive Electrode Terminal

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hideaki Tokugawa 1-1-1 Shimosugishita, Takakura, Hiwada-cho, Koriyama-shi, Fukushima Prefecture Sony Energy Tech Co., Ltd.

Claims (3)

[Claims] 1. A bottomed cylindrical battery can body, a positive electrode mixture arranged in a cylindrical shape on the outer peripheral side of the battery can body, and a separator arranged in the cylindrical positive electrode mixture. In the alkaline battery having a negative electrode mixture, a sealing member that seals the opening at one end of the battery can body, and a current-collecting pin press-fitted into the through hole of the sealing member, the opening of the positive electrode mixture An alkaline battery, wherein the shape of the portion is a stepped shape in cross section along the sealing member. 2. A bottomed cylindrical battery can body is filled with a predetermined amount of a positive electrode mixture, and then a hollow cylindrical upper punch having a convex tip is set on the battery can body, and The middle punch is pushed to a predetermined position of the battery can body through a hole in the center of the upper punch, and the shape of the positive electrode mixture is a hollow cylindrical shape having a stepped cross section at the opening of the battery can body. Method for manufacturing alkaline battery. 3. A bottomed cylindrical battery can body is filled with a predetermined amount of a positive electrode mixture, and then a middle punch is inserted and set to a predetermined position of the battery can body, and then the center punch is placed at the center. A hollow cylindrical upper punch having a convex tip through a hole is pushed into the battery can body, and the shape of the positive electrode mixture is a hollow cylindrical shape having a stepped cross-section at the opening of the battery can body. A method for manufacturing an alkaline battery, comprising: