JPH07122254A - Cylindrical alkaline battery - Google Patents

Abstract

(57) [Summary] [Purpose] The explosion-proof function operates normally even if a resin with a large elongation is used for the sealing body, or the resin of the sealing body is softened and the elongation becomes large when the battery is exposed to high temperature. In addition, a highly safe tubular alkaline battery that can prevent the battery from bursting under high pressure is provided. [Structure] An annular support 7 serving as a support for the sealing body 6 is provided with a triangular projection 72 whose tip faces the sealing body 6 side. For example, when the protrusion 72 is formed by punching out a part of the annular support 7 in a triangular shape to form the gas vent hole 71, one side of the protrusion 72 is left, and the end of the punched portion faces the sealing body 6 side. It is made by folding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical alkaline battery, and more specifically, even if the resin of the sealing body has a large elongation, the explosion-proof function operates normally to prevent the battery from bursting under high pressure. The invention relates to a highly safe tubular alkaline battery.

[0002]

2. Description of the Related Art In a cylindrical alkaline battery, if it is accidentally charged or becomes over-discharged, gas is generated inside the battery, the pressure inside the battery rises abnormally, and the battery bursts under high pressure. Come to do.

For this reason, conventionally, as shown in FIG. 5, the sealing body 6 is provided with an explosion-proof thin portion 66, and when the internal pressure of the battery rises to reach a predetermined pressure, the thin portion 66 is broken. The gas inside the battery to the broken portion of the thin portion 66,
The battery may be provided with a so-called explosion-proof function of preventing the battery from rupturing under high pressure by passing through the gas vent hole 71 of the annular support 7 and the gas vent hole 81 of the negative electrode terminal plate 8 and discharging the gas to the outside of the battery. (For example, JP-A-63-2
No. 36255).

However, in order to break the thin portion 66 of the sealing body 6 and release the gas inside the battery to the outside of the battery as described above, the vicinity of the thin portion 66 is also bent upward depending on the gas pressure inside the battery. Therefore, a thinner connecting portion 63 is provided between the central portion 61 of the sealing body 6 and the thick outer peripheral edge portion 62, and the thickness of the connecting portion 63 is 0.2 to
It is thinned to about 0.5 mm.

Therefore, when a resin having a large elongation is used for the sealing body 6 or the resin of the sealing body 6 is softened by the exposure of the battery to a high temperature and the elongation becomes large, the pressure inside the battery becomes relatively large. Before the thin portion 66 is destroyed at low pressure,
As shown in FIG. 5, the connecting portion 63 expands and bulges upward due to the pressure increase inside the battery, and abuts on the annular support body 7, thereby
Since 3 closes the gas vent hole 71 of the annular support 7, even if the internal pressure of the battery rises and the thin portion 66 breaks, the gas vent hole 71 is closed, so that the gas inside the battery is not exposed to the outside. The battery will burst under high pressure.

[0006]

DISCLOSURE OF THE INVENTION According to the present invention, in the conventional cylindrical alkaline battery, the connecting portion 63 of the sealing body 6 has the annular support 7 before the explosion-proof thin portion 66 is destroyed as described above.
The gas vent hole 71 of is blocked, the explosion-proof function does not operate normally,
Even when the problem that the battery bursts under high pressure is solved and a resin with a large elongation is used for the sealing body 6 or the resin of the sealing body 6 is softened and the elongation becomes large when the battery is exposed to a high temperature, An object of the present invention is to provide a highly safe tubular alkaline battery that has a normal explosion-proof function and can prevent the battery from bursting under high pressure.

[0007]

1 and 2 corresponding to the first embodiment of the structure of the present invention for achieving the above object.
According to the present invention, the annular support 7 is provided with a triangular projection 72 whose tip faces the sealing body 6 side.

Annular support 7 having protrusions 72 as described above
Is produced, for example, by drawing a thin plate of metal such as iron with a press, and the projection 72 leaves one side thereof when the gas vent hole 71 is produced by punching out a part of the annular support 7 in a triangular shape. It is prepared by bending the punched part so that the tip end faces the sealing body 6 side.

[0009]

In the tubular alkaline battery of the present invention, the connecting portion 63 of the sealing body 6 expands and bulges upward due to the pressure increase inside the battery until the explosion-proof thin portion 66 breaks, and the gas of the annular support 7 expands. If the hole 71 is closed,
Since the tips of the triangular protrusions 72 provided on the annular support member 7 pierce the connection portion 63 and destroy the connection portion 63, the gas inside the battery can be reliably discharged to the outside of the battery. Therefore, destruction of the battery under high pressure is prevented, and high safety is ensured.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. However, the present invention is not limited only to the examples.

FIG. 1 is a partial sectional view showing a first embodiment of a cylindrical alkaline battery of the present invention, and FIG. 2 shows an annular support used in the battery shown in FIG. Is a plan view thereof, and (b) is a half sectional view thereof. In the figure showing the battery, if the contour line behind the cross section of each member is illustrated, it is rather complicated, so only the cross section is shown except for the ones particularly necessary, and the contour line behind the cross section is omitted. ing.

In the figure, 1 is a positive electrode mixture, 2 is a negative electrode agent, 3 is a separator, 4 is a positive electrode can, 5 is a negative electrode current collector, 6 is a sealing body,
Reference numeral 7 is an annular support, 8 is a negative electrode terminal plate, and 9 is an exterior material.

The positive electrode mixture 1 is formed by pressure molding a powder mainly containing manganese dioxide and graphite into a cylindrical shape, and the negative electrode agent 2 is a mixture prepared by mixing zinc powder, an alkaline electrolyte and a gelling agent. It consists of The separator 3 is made of non-woven fabric and separates the positive electrode mixture 1 and the negative electrode agent 2.

The positive electrode can 4 is made of iron and has a surface plated with nickel, and the power generating elements such as the positive electrode mixture 1, the negative electrode agent 2 and the separator 3 are contained in the positive electrode can 4. The negative electrode current collector 5 is made of brass and is inserted into the through hole 64 of the sealing body 6, and its head is fixed to the center portion of the inner surface of the negative electrode terminal plate 8 by welding.

The sealing body 6 is made of a resin obtained by injection molding a polyolefin resin, a nylon resin or the like, and its shape is a central portion 61 having a through hole 64 into which the negative electrode current collector 5 is inserted. And an outer peripheral edge portion 62 that contacts the inner peripheral surface of the open end of the positive electrode can 4, and a connecting portion 63 that connects the central portion 61 and the outer peripheral edge portion 62, and the outer peripheral edge portion 62 of the connecting portion 63. A V-shaped portion 65 having a role of guiding the opening end portion of the separator 3 is provided in the vicinity of.

The connecting portion 63 has an annular support 7 which will be described later.
In order to be able to penetrate by piercing the protrusion 72 of
In this embodiment, the thickness is 0.4 mm.
In the present invention, the connecting portion 6 of the protrusion 72 of the annular support 7 is
Since the gas inside the battery is released to the outside of the battery by puncturing the battery 3, the explosion-proof thin wall portion is not always necessary, but may be left as the thin wall portion 66 as shown in FIG.

The annular support 7 is made of an iron plate having a thickness of 0.3 mm and has a surface plated with nickel, and is provided with a gas vent hole 71 and a protrusion 72. This annular support will be described in more detail with reference to FIG. 2. An inner cylindrical portion 73 externally fitted to the central portion 61 of the sealing body 6 and an outer peripheral edge portion 62 of the sealing body 6.
The outer cylindrical portion 74 is inscribed in and the connecting portion 75 that connects the inner cylindrical portion 73 and the outer cylindrical portion 74 to each other, and has a substantially N-shaped cross section. The gas vent hole 71 and the protrusion 72 are provided on the connecting portion 75.

The annular support 7 is manufactured by drawing an iron plate by a press, and the projections 72 are formed on the annular support 7.
When a part of the gas is punched out in a triangular shape to form the gas vent hole 71, one side thereof is left, and the punched part is bent so that the tip faces the sealing body 6 side.

The number of the gas vent holes 71 and the number of the protrusions 72 may be one or more, but it is preferable to provide about four in practice.

Since the tip of the protrusion 72 has a triangular vertex and faces the sealing body 6 side, the pressure inside the battery rises and the connecting portion 63 of the sealing body 6 extends. When it bulges upward and comes into contact with the annular support 7, the projection 72 pierces the connecting portion 63 of the sealing body 6,
As a result, the connecting portion 63 is destroyed.

As a result, the gas inside the battery is discharged to the outside of the battery through the broken portion of the connecting portion 63, the gas vent hole 71 of the annular support 7, and the gas vent hole 81 of the negative electrode terminal plate 8. Since the connecting portion 63 of the sealing body 6 blocking the gas vent hole 71 of the annular support 7 as seen in a conventional battery, the battery does not burst under high pressure, ensuring high safety. To be done.

The direction of the triangle of the gas vent hole 71 may be any direction, but in view of workability during battery assembly, the protrusion 72 may cause a catch on the flow when the annular supports 7 are automatically selected. Therefore, it is better that the protrusion 72 does not protrude from the outer cylindrical portion 74.
In the case of manufacturing, the protrusion of the triangle-shaped gas vent hole 71 is that the apex faces the inner circumference side, the opposite side of the apex is on the outer circumference side, and the tip is bent toward the sealing body 6 side at that side. This is preferable because the tip of 72 can be set to an appropriate position that is closest to the connecting portion 63, which is the puncture breaking point of the sealing body 6.

The negative electrode terminal plate 8 is made of iron and has a surface plated with nickel. Is provided with a gas vent hole 81, the head portion of the negative electrode current collector 5 is welded to the central portion of the inner surface of the ceiling portion, and the peripheral edge portion is bent inward at the opening end portion of the positive electrode can 4. Due to
The upper end portion of the outer peripheral edge portion 62 of the sealing body 6 allows the annular support 7
Is pressed and fixed to the outer peripheral edge of the.

The exterior material 9 is made of a resin-metal composite sheet in which aluminum is vapor-deposited, and insulates the outer peripheral portion of the positive electrode can 4.

FIG. 3 is a partial cross-sectional view showing a second embodiment of the cylindrical alkaline battery of the present invention. The cylindrical alkaline battery of the second embodiment is shown in FIG. 1 except that the shape of the annular support 7 is different. It is constructed similarly to the cylindrical alkaline battery of the first embodiment shown.

The annular support 7 in the cylindrical alkaline battery of the second embodiment has a substantially U-shaped cross section, and the vent holes 71 and the protrusions 72 are produced in the first embodiment. It is manufactured by a method similar to that of Niimono.

FIG. 4 is a partial sectional view showing a third embodiment of the cylindrical alkaline battery of the present invention. The cylindrical alkaline battery of the third embodiment is shown in FIG. 1 except that the shape of the annular support 7 is different. It is constructed similarly to the cylindrical alkaline battery of the first embodiment shown.

The annular support 7 in the cylindrical alkaline battery of the third embodiment has a semi-reverse cross section of a substantially inverted U-shape, and the degassing holes 71 and the protrusions 72 are produced in the first embodiment. It is manufactured by a method similar to that of the example.

Next, the batteries of the first to third embodiments and FIG.
As shown in (4), a battery having a conventional structure in which only the thin portion 66 has an explosion-proof function (conventional example) was examined for burst resistance when the battery was forcibly charged. The details are shown in Test Examples 1 and 2.

First, the batteries to be tested are
It is divided into A series and B series. In A series, a sealing body made of polypropylene with a large elongation (elongation at 23 ° C: 600%) is used, and a forced charge test is performed at 23 ° C. Then, a sealing body made of nylon 66 (elongation 200% at 23 ° C.) was used, and a forced charge test was performed at a high temperature of 120 ° C., which was referred to as Test Example 2. Details of Test Example 1 and Test Example 2 are as follows.

Test Example 1: Polypropylene (2
A product made from an elongation of 3% at 600%) was used, and a forced charge test was performed at 23 ° C.

All batteries have an outer diameter of 14.5 mm and a total height of 5
It is a 0.5 mm LR6 type cylindrical alkaline battery, and the number of batteries used in the test was 20 each. In the test, the number of batteries that ruptured, the number of batteries that swelled and the connection part of the sealing body were The number of batteries that expanded and swelled upward and contacted the annular support was examined.

The results are shown in Table 1.
In order to make it easy to understand the number of batteries that have burst in all the batteries used in the test, the denominator indicates the total number of batteries used in the test, the number of batteries that have burst in the numerator (the number of batteries that have burst), and the The number of generated batteries (number of swelling-generated batteries) and the number of batteries in which the connecting portion of the sealing body extends and swells upward to contact the annular support (contact battery number) are shown.

[0034]

[Table 1]

As is clear from the results shown in Table 1, the batteries of Examples 1 to 3 of the present invention were
In all cases, there was no rupture or blistering, and we were able to secure high safety. On the other hand, in the battery having the conventional structure, swelling occurred in 11 out of 20 batteries used in the test, and 6 batteries ruptured.

From the results shown in Test Example 1, according to the present invention, even when polypropylene which has a large elongation and is inexpensive is used for the sealing body 6, the battery is prevented from bursting under a high pressure due to forced charging or the like, so that the safety is high. It is understood that it is possible to secure the sex.

This is because the pressure inside the battery rises, the connecting portion 63 of the sealing body 6 expands and bulges upward, and the annular support 7
When it comes into contact with the circular support 7, the projection 72 provided on the annular support 7 pierces the connecting portion 63 of the sealing body 6 and destroys the connecting portion 63. The gas vent hole 71 of the support 7 is not completely blocked by the connecting portion 63 of the sealing body 6,
As a result, the gas inside the battery can go out of the battery through the broken portion of the connecting portion 63, the gas vent hole 71 of the annular support 7 and the gas vent hole 81 of the negative electrode terminal plate 8. .

Test Example 2: Nylon 66 (23
Use a product made from 200% elongation at ℃) and force charging 1
A forced charge test was performed on a B series battery under the same conditions as in Test Example 1 except that the test was performed at a high temperature of 20 ° C. The results are shown in Table 2. The method of displaying the test results is the same as in Test Example 1.

[0039]

[Table 2]

As is clear from the results shown in Table 2, in the case of forced charging at high temperature, in the battery having the conventional structure, swelling occurred in 9 out of the 20 batteries tested.
Although three batteries ruptured, all of the batteries of the first to third embodiments of the present invention showed no rupture or blistering,
We were able to ensure high safety even when forcedly charged at high temperatures.

The results shown in Test Example 2 show that even when nylon 66 having a small elongation is used for the sealing body 6, when the battery is exposed to a high temperature and the resin of the sealing body 6 softens to increase the elongation, the conventional structure is obtained. When the internal pressure of the battery rises due to gas generation inside the battery due to forced charging,
Although the connecting portion 63 of the sealing body 6 expands and bulges upward, the gas vent hole 71 of the annular support 7 is closed and the battery bursts under high pressure. However, according to the present invention, the battery may be ruptured under such high temperature. Even during forced charging, the protrusions 72 provided on the annular support 7 can break the connecting portion 63 of the sealing body 6 and release the gas inside the battery to the outside of the battery. Therefore, it is possible to prevent the battery from bursting under high pressure. , Shows that high safety can be secured.

[0042]

As described above, according to the present invention, the triangular protrusion 72 of which the front end faces the sealing body 6 side is provided on the annular support 7.
Due to the provision of the above, the explosion-proof function operates normally even when a resin with a large elongation is used for the sealing body 6 or when the resin of the sealing body 6 is softened and the expansion becomes large when the battery is exposed to a high temperature. As a result, the battery is prevented from bursting under high pressure and high safety can be secured.

That is, even when an inexpensive resin having a large elongation such as polypropylene is used for the sealing body 6, the pressure inside the battery rises and the connecting portion 63 of the sealing body 6 expands and bulges upward to form the annular support 7. When it comes into contact with the annular support member 7 to close the gas vent hole 71 of the annular support member 7, the annular support member 7
The protrusion 72 provided at the end pierces the connecting portion 63 of the sealing body 6 to destroy the connecting portion 63, and allows gas inside the battery to pass through the destroyed portion, the gas vent hole 71 of the annular support 7 and the like to outside the battery. Since it is released, it is possible to prevent the battery from bursting under high pressure and ensure high safety.

Even when the battery is exposed to a high temperature and the resin of the sealing body 6 is softened and the elongation becomes large, the explosion-proof function normally operates in the same manner as described above, and the battery does not burst under high pressure. It can be prevented and high safety can be secured.

[Brief description of drawings]

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

2A and 2B show an annular support used in the battery of the first embodiment shown in FIG. 1, in which FIG. 2A is a plan view thereof, and FIG. 2B is a half sectional view thereof.

FIG. 3 is a partial cross-sectional view showing a second embodiment of the cylindrical alkaline battery of the present invention.

FIG. 4 is a partial cross-sectional view showing a third embodiment of the cylindrical alkaline battery of the present invention.

FIG. 5 is a partial cross-sectional view showing a conventional cylindrical alkaline battery.

FIG. 6 shows a state in which the connecting portion of the sealing body of the conventional cylindrical alkaline battery shown in FIG. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Positive electrode mixture 2 Negative agent 3 Separator 4 Positive electrode can 5 Negative electrode current collector 6 Sealing body 61 Central portion 62 Outer peripheral edge portion 63 Connection portion 64 Through hole 65 V-shaped portion 66 Thin wall portion 7 Annular support body 71 Gas vent hole 72 Protrusion 8 Negative electrode terminal plate 81 Gas vent hole

Claims (5)

[Claims] 1. A sealing member 6 made of a resin, an annular support 7 having a gas vent hole 71 and serving as a support for the sealing member 6, an opening of a positive electrode can 4 containing a power generating element, and the sealing member. In a cylindrical alkaline battery, which is sealed with the negative electrode current collector 5 inserted into the through hole 64 of the central portion 61 of the body 6, a triangular protrusion 72 whose tip faces the sealing body 6 side is provided on the annular support 7. A cylindrical alkaline battery characterized by being provided. 2. The annular support 7 is produced by drawing a thin metal plate, and the projection 72 thereof punches out a part of the annular support 7 in a triangular shape to form a gas vent hole 71.
2. The cylindrical alkaline battery according to claim 1, wherein one side is left when manufacturing, and the punched portion is bent so that the tip faces the sealing body 6 side. 3. The cylindrical alkaline battery according to claim 1, wherein the half-section cross section of the annular support 7 is substantially N-shaped. 4. The tubular alkaline battery according to claim 1, wherein the half-section of the annular support 7 is substantially U-shaped. 5. The tubular alkaline battery according to claim 1, wherein the half-section of the annular support 7 is substantially inverted U-shaped.