JPS58198871A - Button type air cell - Google Patents

Abstract

PURPOSE:To prevent any scratch to the inner wall of a case from occurring at the time of inserting a catalytic layer into the case, by setting up two-step parts at the bottom part of a positive pole case in a constricted form, while installing a water-repellent membrane and the catalytic layer in the first step part and a separator in the second step part respectively. CONSTITUTION:Two-step parts 1a and 1b are set up at the bottom part of a positive pole case 1 in a constricted form, and an air diffusion paper sheet 3 is inserted into the positive pole case 1 making up an air hole 2. Next, in the first step part 1a, a water-repellent membrane 4 and a catalytic layer 5 are disposed, then likewie a separator 6 is installed in the second step part 1b and assembly body at the positive pole side is thus completed. And, an elastic sealing ring 7 is attached to the periphery of a sealing plate 8 and then this button type air cell being combined with a negative pole sealing body where a negative pole 9 and an electrolyte are inset inside is formed up. Accordingly, when the catalytic layer 5 is inserted into the cell case, there are no scratches to the inner wall of the positive pole case 1 by a metal core material so that a rise in internal resistance based on a solution leakage or a contact failure can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a button-type air battery with improved leakage resistance and discharge performance by providing two constricted steps at the bottom of the positive electrode case.

A conventional button-type air cell was constructed as shown in FIG. That is, an air diffusion paper 3 is placed on the inner bottom of a positive electrode case 1 having an air supply hole 2 at the bottom, and a fluororesin water-repellent film 4 is placed on top of this from the bottom side of the positive electrode case 1. Catalyst layer5.
Separators 6 are stacked in this order to complete the positive electrode assembly.

The negative electrode sealing body is completed by filling a sealing plate 8 with a sealing ring 7 fitted around the periphery with a negative electrode active material 2 made of zinc (red 9) and an alkaline electrolyte.

By fitting the positive electrode side assembly and the negative electrode sealing body and caulking the opening of the positive electrode case 1 inward, one button-type air battery is completed.

However, when such a positive electrode case is used, it is difficult to insert the catalyst layer 5 into the case if the outer diameter of the catalyst layer 6 is the same as or larger than the inner diameter of the positive electrode case 1. Furthermore, when the catalyst layer is inserted, scratches may occur on the inner wall of the positive electrode case due to the metal core material of the catalyst layer, and these scratches make it impossible to completely seal the case against sunlight, which has the disadvantage of poor leakage resistance. was there. In addition, when the outer diameter of the catalyst layer is smaller than the inner diameter of the positive electrode case, poor contact between the positive electrode case and the catalyst layer and an increase in internal resistance.

This resulted in low discharge performance, etc., making it undesirable.

In order to solve this problem, the present invention provides two constricted steps at the bottom of the positive electrode case, and configures the positive electrode part using this positive electrode case.

According to the present invention, the inner wall of the positive electrode case is not damaged when the catalyst layer is inserted, and the contact between the catalyst layer and the positive electrode case is prevented by the tightening force when sealing the battery. ■Low internal resistance and improved leakage resistance.

It is possible to stabilize the discharge performance.

The present invention will now be explained in detail with reference to an embodiment of a button-type air cell as shown in FIG.

First, an air diffusion paper 3 made of cellulose is placed in a positive electrode case 1 which has two constricted steps 1a and 1b at the bottom and an air hole 2, which is a feature of the present invention.

Next, the water-repellent film 4 is inserted into the first step 1a from the bottom of the positive electrode case 1. Then, on top of that, a catalyst layer 6 filled with a dissolving material made of a nickel net mixed with activated carbon, acetylene black, and polytetrafluoroethylene as a binder.
Insert. Finally, the separator 6 is installed on the second step 1b from the bottom of the positive electrode case 1 to complete the positive electrode side assembly. Apart from this, synthetic resin or
An elastic sealing ring 7 made of synthetic rubber is attached, and a negative electrode 9 made of frozen zinc powder with a binder added and an aqueous potassium hydroxide solution are injected into the ring to complete the negative electrode sealing body.

Both the negative electrode sealing body and the positive electrode assembly manufactured in this way are fitted together, the opening of the positive electrode case 1 is bent inward, and the periphery of the sealing plate 80 is tightened via the sealing ring 7, thereby forming a catalyst layer. The periphery of 6 is pressed against the constricted inner bottom surface of the case via a separator to complete a button-type air battery.

As shown in the table below, the leakage resistance and internal resistance value of the battery of the present invention are as shown in the table below. Significant differences were found in gender. Furthermore, a difference in internal resistance was observed when compared with a battery using a method in which the outer diameter of the catalyst layer was reduced so that it did not come into contact with the inner wall of the positive electrode case.

The battery of the present invention is A, the battery using the conventional positive electrode case is B, and the battery in which the outer diameter of the catalyst layer is smaller than the inner diameter of the positive electrode case is C. Leakage rate and 2o°9 矧2 when stored for 2 weeks
The following table shows a comparison of internal resistance values measured after storage for 4 hours or more.

As is clear from the results of 6 Behmi or more, the present invention was able to solve the problem of the increase in internal resistance caused by leakage and poor contact between the catalyst layers during storage of the battery.

In this example, the second step from the bottom of the positive electrode case is 0.2 trrm smaller than the maximum outer diameter of the positive electrode case.
A positive electrode case was used that was formed at a position 5 mm higher than the bottom of the first step. Furthermore, although a nickel-plated steel plate was used as the material for the positive electrode case, a stainless steel plate is also applicable.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a conventional button-type air battery, and FIG. 2 is a cross-sectional view of a button-type air battery according to an embodiment of the present invention. 6 beko! 1...Positive electrode case, 1a, 1b...Stepped portion, 2...Air hole, 3...Air diffusion paper, 4... Water repellent film, 6... Catalyst L 6.
...Separator, 7...Sealing ring,
9...Negative electrode. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure q8 Figure 2

Claims (1)

[Claims] The positive electrode case has two constricted steps at the bottom, a water-repellent membrane and a catalyst layer are installed at the first step from the bottom, and a separator is installed at the second step. Button type air battery.