JPS5817331Y2 - alkaline battery - Google Patents

Description

[Detailed description of the invention] The present invention relates to an explosion prevention structure for alkaline dry batteries.The invention relates to an explosion prevention structure for alkaline dry batteries. At least one sharp cut and raised part is provided in the part, and the tip part acts as a needle to pierce the synthetic resin sealing body when the internal pressure increases, and the remaining hole of the cut and raised part is used as a gas dissipation hole. .

Furthermore, by covering the gas dissipation holes drilled in the synthetic resin sealing body with an insulating ring such as an elastic synthetic resin or rubber ring provided on the outside, the electrolyte that tries to leak out with the gas can be suppressed. An object of the present invention is to provide an alkaline dry battery having an inexpensive sealed structure that is extremely safe.

When alkaline batteries are charged or over-discharged and polarized, a violent gas-generating reaction occurs inside them.

Of course, if charging is performed externally with a charger or the like that causes gas generation, but if a device that uses multiple batteries is loaded with the wrong polarity of one battery, for example, When operating a device or using a mixture of old and new batteries, a gas generation reaction may occur in reverse-loaded batteries or old batteries, which may lead to leakage or rupture. .

As a countermeasure to these problems, various burst prevention measures have been incorporated into the battery body in the past.

The simplest method is to weaken the sealing strength between the sealing members and allow gas to dissipate from the gap between the sealing members.
Generally, the caustic potash electrolyte used in alkaline batteries has a large creep property, so if the sealing strength is weakened, the electrolyte will leak from the gap between the sealing members just by storing it.
It becomes useless as a battery.

Conversely, if the sealing strength is increased and the degree of adhesion between the sealing members is increased, at the same time a part of the sealing member itself has a weaker strength part, the weaker strength part will be able to resist pressure above a certain level. A method of destroying the is also adopted.

For example, if a thin wall part is provided in a synthetic resin and gas is generated, there is a method in which the gas pressure causes deformation or cracks in the thin wall part to dissipate the gas, or a method in which a thin wall part is provided in the synthetic resin and the thin wall part is complicated. A method of destroying thin-walled parts by placing cut parts with different shapes facing each other, and using a sharp part cut and raised from a part of the outer plate usually made of pot metal to cut metal foil, thin-walled parts, or resin. □This is a method of destroying the inner sealing plate.

However, with these methods, the gas dissipation pressure is not constant, and although the gas dissipation function is reliable, the alkaline electrolyte that is the battery contents dissipates at the same time as the gas, causing leakage. It had the following drawback.

This invention does not require a special thin part in the synthetic resin.
By using at least one sharp cut-and-raised portion provided near the periphery of the terminal bottom plate as a breaking member of the sealing body,
When the sealing body deforms and bulges toward the terminal bottom plate when gas is generated, the synthetic resin sealing body is very easily and reliably perforated with the sharp cut and raised part to dissipate the gas and prevent liquid leakage at the same time. It is something to prevent.

Examples thereof will be described in detail below using figures.

FIG. 1 is a half-cut side view of an alkaline manganese battery embodying the present invention.

A positive electrode mixture 2 made of manganese dioxide and graphite is formed into a cylindrical shape in a battery case 1 that also serves as a positive electrode terminal, and a negative electrode gel material 3 made of caustic potash, a viscous substance, and unformed zinc is placed inside of it, and a separator 4 is placed therein. A groove is formed in a part 5 of the battery case 1 to form a resin sealing body 6. The negative electrode current collector 7 and the negative electrode terminal bottom plate 8 are inserted into the battery case 1, and the opening 9 of the case is rolled up to form a unit cell.

As shown in FIG. 2, a sharp cut-and-raised portion 10 is provided at the peripheral rising portion provided near the periphery of the negative electrode terminal bottom plate 8.
The tips thereof face the sealing body 6.

The remaining hole 10a of this cut-and-raised portion forms a gas dissipation hole, and this hole 10a is completely covered from the outside by a rubber insulating ring 12 placed between the outer edge 11 and the lower end of the battery case 1. It is being said.

Further, 13 is a heat-shrinkable tube that insulates the exterior edge 11 and the battery case 1, 14 is a positive electrode cap portion, and 15 is a sealant for preventing liquid leakage applied to the contact portion between the negative electrode current collector and the negative electrode terminal bottom plate. It is.

Exterior edge 11 that tightens the aforementioned rubber insulating ring 12
The bent end 16 ゛ is as long as possible for the insulating ring 12
It holds well, is highly effective in preventing electrolyte leakage, and works well as a valve body.

Further, the distance between the negative electrode terminal bottom plate 8 and the bent tip of the exterior edge is preferably 1.0 to 2.0 mm.

1. If the distance is closer than 0 mm, the electrical insulation between the exterior edge and the bottom plate will deteriorate; If the distance is more than 0 mm, the function of the insulating ring as a presser will be reduced, and the effect of preventing electrolyte leakage will be poor.

The LR20 type battery of this embodiment of the present invention is designated as A, and has the same structure as that in FIG. 1, with a part of the synthetic resin sealing body having a
Q. A conventional LR20 type battery with a thin wall of 5 mm is designated as B, and a battery with no thin wall at all is designated as C. One of the four batteries is reversely loaded, and three batteries have a resistance of 0.5 Ω. By charging one reverse-loaded battery through an external resistor, the effect of preventing battery explosion and leakage can be increased by 10%.
The test was conducted using 0 sets of batteries.

The effect is shown in the table below. As is clear from the table below, the invention has a significant effect.

The reason for this is thought to be that due to the molding technology of the synthetic resin sealing body, it was not possible to obtain a uniform thin part, and among them, the thick part similar to C burst.

In addition, the present invention has the advantage that the gas dissipation pressure can be adjusted by adjusting the length of the cut-and-raised part, and it is extremely difficult to create thin parts that break at a pressure of 20 kg/am2 or less in a plastic sealing body due to molding technology. However, in the case of the present invention, the destruction can be adjusted extremely easily.

Also, some of the contents may leak out at the same time as the gas dissipates, but the gas dissipation hole is covered with an elastic insulating ring.
Since this ring acts as a valve body, leakage can be reduced.

In the above-mentioned embodiment, only one cut-and-raised portion is provided, but in order to further ensure that the sealing body is not destroyed during deformation, two or three cut-and-raised portions may be provided.

Even in this case, all the cut-and-raised portion remaining holes can be closed with one elastic insulating ring.

As described above, the battery of the present invention has an extremely simple structure and excellent explosion-proof function.

[Brief explanation of drawings]

FIG. 1 is a half-cut side view of an alkaline manganese battery according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of the main parts of the battery. DESCRIPTION OF SYMBOLS 1...Battery case, 6...Synthetic resin sealing body, 8...Terminal bottom plate, 10...Cut and raised portion, 10a...・Remaining hole in cut and raised part, 12...Elastic insulating ring.

Claims (1)

[Scope of utility model registration request] The opening of the battery case is sealed with a synthetic resin sealing body, and at least one sharp cut-and-raised portion is provided near the periphery of a terminal bottom plate disposed outside the sealing body to face the sealing body, and the terminal bottom plate is provided with: An alkaline battery whose cut-and-raised hole is covered with an elastic insulating ring.