JPS58129748A - Enclosed cell - Google Patents

Abstract

PURPOSE:To prevent deformation of a sealing plate at sealing and improve the leakproof of liquid, by modifying the shape of a molded positive pole. CONSTITUTION:When a positive pole compound is molded, a slope of 5-15 deg. (theta in the drawing) is provided in a positive pole ring as shown by the drawing correspondingly to a finished shape of a molded positive pole. If the positive pole ring in such a shape is used, density of the positive pole compound is relatively equalized to prevent separation of the positive pole ring due to buckling in the upper periphery of the positive pole compound and enable the improvement of moldability. While in case of using said positive pole ring, when a slope corresonding to the slope of the positive pole ring is provided to the upper periphery also of a primary molded article (positive pole pellet) of the positive pole compound, a better molded positive pole can be obtained. That is, reaction of said sloped surface causes a seal plate and seal packing not to deform for the force which tends to internally deform the seal plate and seal packing at sealing, and a sealing condition as designed can be realized to improve leakproof of liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for making the opening of a battery case containing all power generating elements, such as a silver oxide battery, mercury battery, lithium battery, etc., liquid-tight with a sealing plate through an insulating sealing packing. Regarding sealed batteries, by improving the shape of the molded positive electrode, we can prevent the sealing plate from deforming during sealing, eliminate incomplete sealing caused by deformation of the sealing plate, and improve leakage resistance. Another object of the present invention is to reduce the internal resistance of the battery by eliminating the sagging of the electrolyte-impregnated material and the cell plate due to deformation of the sealing plate.

The present invention will be described below with reference to drawings showing a fourth embodiment thereof.

FIG. 1 is a schematic cross-sectional view of a conventional button-type silver oxide battery.

FIG. 2 is a schematic cross-sectional view of a button-type silver oxide battery using the positive electrode ring according to the present invention, and FIG. 3 is a cross-sectional view of the positive electrode ring according to the present invention. 1 is a cylindrical metal case with one bottom, and 2 is a positive electrode mixture placed at the inner bottom of the case 1, which is made by press-molding a mixed powder of silver oxide, graphite, etc. 3 is a separator placed on the positive electrode mixture 2, and 4 is an electrolyte-impregnated material placed on the separator 3 and impregnated with an alkaline electrolyte. Reference numeral 5 denotes a negative electrode mixture disposed on the lubricating material 4, which is made of a mixed powder of frozen zinc, a thickener, and the like. 6 and 6' are ring-shaped insulating seals/gucking with a cross section of 2 and a letter shape, and are made of synthetic rubber with excellent elasticity and flexibility or synthetic resin with excellent aging resistance and mechanical strength.

7 H sealing n A single metal sealing plate having a substantially inverted dish shape that closes the opening of the case 1 with the backing 6 interposed therebetween, and the periphery thereof is provided with a bulging portion 7a and a U-shaped continuous portion 7b. There is. 8
, 8' are positive electrode rings used because the strengths of the molded jfF electrodes are similar.

In the case of a conventional battery (FIG. 1), the horizontal component of the force acting on the battery during sealing is directed toward the center of the battery as shown by arrow A, and the sealing plate 7 deforms inward together with the sealing and lagging 6.

As a result, the compressibility of the sealing backing 6 was not as designed, and an ideal sealing condition could not be obtained, which was the cause of liquid leakage. Also, the sealing plate 7. Along with the inward deformation of the sealing 6, the separator 3 and electrolyte impregnating agent 4 placed on the positive electrode mixture 2 are also pushed toward the center, causing wrinkles on the positive electrode mixture 2. The internal resistance of the battery was increased because an air layer was formed there.

On the other hand, in the case of the battery of the present invention (Fig. 2), the part corresponding to the lower surface of the sealing/tacking on the upper outer periphery of the molded positive electrode is 5° to 15° ( An inclination of θ) in the figure is provided.The sealing plate, sealing plate, sealing plate, sealing plate, sealing plate, sealing plate, etc. are inclined due to the reaction force of the slope shown in the figure. The gasket does not deform and can be sealed as designed, resulting in improved leakage resistance. Also, Ce Greta.

It also eliminates sagging of the impregnating agent, and since there is no air layer, the internal resistance of the battery can be lowered.

When molding the positive electrode mixture as in the present invention, the positive electrode ring is inclined at an angle of 5 to 15 degrees (θ in the figure), as shown in FIG. 3, to correspond to the shape of the formed positive electrode. When such a positive electrode ring 4 is used, the density of the positive electrode mixture becomes relatively uniform, it is possible to prevent separation of the positive electrode ring due to the pack ring on the upper outer periphery of the positive electrode mixture, and it is possible to improve moldability.

Additionally, when using the above positive electrode ring, a better molded positive electrode can be obtained if the primary molded product of the positive electrode mixture (positive electrode baglet) is also provided with a slope corresponding to the slope of the positive electrode ring on the upper outer periphery. confirmed experimentally.

Table 1 shows silver oxide battery A according to the present invention and silver oxide battery B using a conventional molded positive electrode with a flat top surface.
The results of comparing the number of batteries that caused leakage when 100 of each battery were stored in an atmosphere with a humidity of 45° C. and a relative humidity of 80 to 90% are shown.

<Table 1> R44 Fig. 4 shows the change over time in the average value of internal resistance of 50 batteries each of batteries A and B.

As described above, according to the present invention, a sealed battery with excellent leakage resistance and low internal resistance can be obtained.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of a battery using a conventional positive electrode ring.
FIG. 2 is a schematic cross-sectional view of a battery using the positive electrode ring according to the present invention, and FIG. 3 is a graph showing changes over time in the internal resistance of the positive electrode according to the present invention. 1...Battery case, 2,2'...Positive electrode mixture, 3...
・Secretator, 4... Electrolyte-containing lubricant, 5... Negative electrode mixture, 6.6'... Sealing/zocking, 7... Sealing plate,
7a... Sealing plate bulging part, 7b... Sealing plate rising part,
8, 8'... Positive electrode ring. Patent applicant Matsushita Electric Industrial Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 2' Figure 4 1 2 3 4 shares 4 period (th)

Claims (1)

[Claims] The battery case and the seal that seals the opening of this case [-]
A sealed battery in which the power generating element is sealed by sealing the power generating element by the -1 plate, the battery case and the seal [-1 plate interposed between the battery case and the seal [-1 backing], the outer periphery of which is inclined in the [- direction] This is a sealed battery that uses a positive electrode ring.