JPS60207251A - Enclosed type cell - Google Patents

Abstract

PURPOSE:To improve the leaktightness of the captioned cell by specifying the straightness of the upper end horizontal part of a metal spacer to a particular value. CONSTITUTION:Provided that the straightness of a metal spacer 4 is larger, sealing pressure gets nonuniform whereby an electrolyte leaks out of a cell while passing through between a gasket and a sealing cover or between the gasket and a case. However, with the straightness being made smaller, the pressure becomes uniform whereby the electrolyte is prevented from leaking out. According to the present invention, the straightness f of the upper end horizontal part of the metal spacer 4 is limited to within 0.04mm. whereby the sealing pressure is uniformized and thus the leaktightness of the cell is improved. A good straightness metal spacer can be provided by properly selecting elongation differences among the directionalities of rolling of a raw material plate as well as the processes of batren and drawing, keeping metal mold accuracy, and improving the setting of a metal mold.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a sealed battery in which a positive electrode material is fixed in a metal case using a metal spacer with an inverted cross-section.
It can be used in mercury oxide batteries, silver oxide batteries, alkaline manganese batteries, etc.

Conventional Structure and Problems There will be explained a general structure of a sealed battery with reference to FIGS. 1, 2, and 3. FIG. 1 shows a so-called button-type battery, FIG. 2 shows a metal spacer used therein, and FIG. 3 is a half-sectional view of a cylindrical battery.

In FIG. 1, reference numeral 1 denotes a steel case whose surface is nickel-plated, and has a cylindrical rising portion 2 at its periphery. 3 is a positive electrode material, 4 is an inverted cross section with a lower end 6 reaching the bent part of the inner bottom surface of the metal case, a side surface inscribed in the cylindrical rising part 2 of the metal case, and a horizontal part 6t extending inward at the upper end. It is a square-shaped spacer, and is usually made of nickel-plated steel plate or
Or made of stainless steel. The positive electrode material 2 is fixed within the case 1 by this spacer. 7 is a separator containing an electrolytic solution, and 8 is a negative electrode material made of an electrolytic solution and zinc particles. Ganai filling, 1 metal crack □l a, that. Tsu edge;. .

It is supported by an insulating gasket 11 made of Naishin or the like. In the final process of battery assembly, the tip 12 of the cylindrical rising portion 2 of the metal case 1 is bent inward.

The gasket 11 and the edge 10 of the sealing lid are pressed to seal liquid-tightly.

Figure 3 shows an example of a cylindrical type, in which the positive electrode material 3', the separator 7', and the negative electrode material 9' are arranged vertically in concentric circles from the outside to the inside, so that the separator is sandwiched between the spacer casket and the negative electrode material 9'. Although not unusual, the structure of the seal is basically the same as that of the button-type battery shown in FIG.

Due to the sealing, the tip of the cylindrical rising portion of the metal case presses inward to the gasket 11 and the sealing lid edge 10i, but at the same time, the downward pressing force also moves. Since the positive electrode material 3 is made of hardened powder and is not a body, the surrounding area is dented without being able to withstand this pressure, so the sealing pressure does not increase and it is difficult to become liquid-tight. The spacer stops this deformation of the positive electrode material, receives the sealing pressure at the upper horizontal part, and is supported by the cylindrical part 4 and the lower end 5.

Now, if the shape of the spacer is uneven in the height direction as shown in Figure 4, the pressure will be particularly uneven, and the sealing lid will not be able to remain horizontal to the inner bottom surface of the metal case 1. As a result, the leakage resistance becomes poor.

OBJECTS OF THE INVENTION The present invention is intended to eliminate such conventional drawbacks.
1 or less.

According to J Engineering 5Bo621 "Definition and Indication of Shape and Position Accuracy", straightness is defined as "straightness".

It is defined as the amount of deviation of a straight line from a geometric straight line. In the metal spacer shown in FIG. 4, the straightness of its upper horizontal portion is represented by j, and in the present invention, this j' is within 0.04 n+m.

DESCRIPTION OF THE EMBODIMENTS As already mentioned, in FIG.
If the straightness of the spacer is large, the sealing pressure will be uneven, and the electrolyte will flow between the gasket and the sealing lid or between the gasket and the case from a place where the pressure is low, generally the rising part of the spacer. leaks to the outside through the space between the If the straightness is small, the pressure will be uniform and no leakage will occur.

Machined parts require not only so-called dimensional accuracy.

The accuracy of shape and position is also extremely important, but the present invention is suitable for the straightness of the upper horizontal part of the metal spacer.
By keeping the pressure within this range, the sealing pressure can be made uniform and the leakage resistance of the battery can be improved.

A metal spacer with good straightness is determined by the difference in elongation due to the direction of rolling of the plate material, by selecting an appropriate punching and drawing process, by maintaining mold accuracy, and by improving mold setting. etc. can be obtained.

The reason why the straightness was set to within 0.04 mm was that a battery leakage test revealed that a straightness within 0.04 [11 m] would not cause any practical problems.

Now, the outer diameter of the battery is 11.6mm, the height is j4ff1m + the height of the spacer is 2. A mercury oxide battery of O, mm was used for testing.

The test method is to test the battery at a temperature of 46±2°C, relative humidity of 9.
Continuously stored at 0-96% for 100 hours.

After taking it out and leaving it at room temperature and humidity for 3 days, it was observed under a 10x microscope to determine the presence or absence of leakage.

Upper horizontal part of the spacer. Straightness classification Cheat x number m liquid number 0-02 mm
Below 20 0 0+021~0+030mm 20 00-031~0
．． 040 碓 20 0 0.041 mm or more 20 6 Effects of the Invention In this way, the straightness of the upper horizontal portion of the metal spacer can be reduced to 0.
Setting the distance within 0.4fl1 m has a very significant effect in improving the leakage resistance of the battery.

[Brief explanation of the drawing]

Fig. 1 is a half-sectional view of a button-type battery using a metal spacer with an inverted cross-section, and Fig. 2 is a half-sectional view of the same metal spacer.
Figure 3 is a half-sectional view of a cylindrical battery using a metal spacer.
FIG. 4' is a half sectional view for explaining the straightness of the metal spacer. 1... Cylindrical metal case, 2... Group cylindrical rising part, 3, 3'... Positive electrode material, 4...
Gold maple spacer with inverted cross-section, 6...Lower end of spacer, 6...Horizontal part of upper end, 7, 7'...
Separator, 8...Sealing lid, 9°9'...
- Negative electrode material, 11... Insulating gasket. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] In a cylindrical metal case having a rising portion on the periphery, the lower end reaches the bent portion of the inner bottom surface of the metal case, the side surface is inscribed in the cylindrical rising portion of the metal case, and the upper end extends inward. The positive electrode material is fixed by a metal spacer with a horizontal section and an inverted cross section, and an insulating gasket that supports the sealing lid is placed on the horizontal part of the spacer, and the gasket and the sealing lid are placed in the 9th part of the metal case. A sealed battery in which the tip of the metal spacer is tightened by bending the entire end inward, and the power generation element is sealed, the straightness of the horizontal part of the upper end of the metal spacer being within 0.04 mm.