JPS5841630B2 - sealed alkaline storage battery - Google Patents

Description

[Detailed description of the invention] The present invention relates to an alkaline storage battery with improved sealing.

Conventionally, in a sealed alkaline storage battery equipped with a mesh seal, the creep or twisting phenomenon of the internal alkaline electrolyte through the seal during use cannot be avoided.
There were no reliable preventive measures to prevent this.

That is, conventionally, this type of battery has a pole penetrating the battery container wall, usually the metal lid wall! In AI5, an annular ceramic body is interposed between the through hole and a pole pillar passing through the hole, and there is a gap between the pole pole and the inner circumferential surface of the ceramic body and between the inner circumference of the metal lid hole and the outer circumferential surface of the ceramic body. In between, each solder has a seal part with a bonded structure, but the solder part often has extremely fine holes in the seal part due to manufacturing, and in some cases, the ceramic body itself also has extremely fine holes. Has holes.

Therefore, due to electrophoresis of the alkaline electrolyte, a creep phenomenon inevitably occurs in the ceramic seal portion.

The amount of helium gas leak is I x 10' atmc
Even if the battery is at about c/see, electrolyte leakage or fluting occurs when the storage battery is left for a long period of time.

Usually, a metal battery lid including the hermetic part is manufactured before being assembled into a storage battery, and brazing metal, ie, Ag, is used in the gap between the ceramic body and the pole column and the gap between the ceramic body and the metal lid.

Aup Ni-Ag alloy, Ag-Cu alloy, etc. acid solder is inserted, and these parts are soldered and sealed through high-temperature heat treatment to obtain a lid with a so-called hermetic seal, but this heat treatment process During brazing, extremely fine pores are generated in places due to decomposition gas, etc.

In the past, the formation of such micropores was unavoidable, but even if a synthetic resin liquid is applied to the surface of the seal and dried to form a coating layer of sealant, it is difficult to prevent cracks from forming during use. If this occurs, the sealing action may be destroyed and the above-mentioned sealing portion may easily undergo creep or twisting phenomena through the cracks, and the prevention effect thereof is insufficient and lacks reliability.

The present invention provides a highly reliable and even better sealed alkaline storage battery that reliably prevents such inconveniences and sufficiently maintains the preventive effect over a long period of time. The seal part is impregnated with an alkali-resistant fluid by vacuum suction.

The alkali-resistant fluid is usually made into a liquid or viscous state by heating and melting epoxy resin, silicone resin, or other synthetic resin, or by dissolving it in a solvent.
It is more preferable that the material filled in the sealing portion be in a solidified state.

Usually, the coating is applied to the entire sealing part, and if there are micropores in the ceramic body, the coating is impregnated into them.

The impregnation means is vacuum reduction.

The present invention is usually carried out when manufacturing battery lids for alkaline storage batteries, and after manufacturing a battery lid with a hermetic seal part by a conventional method, it is subjected to the above-mentioned impregnation treatment to fill the ultra-fine pores in the seal part. It is obtained in a state filled with the impregnating agent.

An example of this will be explained with reference to the attached drawings. In the drawings, 1 is an iron battery cover, 2 is a metal pole inserted into the through hole, and 3 is an annular ceramic body fitted and interposed between these.
The inner and outer peripheral surfaces of the ceramic body are previously subjected to metal surface treatment.

4, a seal portion is brazed by a conventional method between the outer circumferential surface of the pole column 2 and the inner circumferential surface of the ceramic body 3, and between the outer circumferential surface of the ceramic body 3 and the circumference of the hole of the metal lid 1. show.

The hermetic seal portion a of the lid manufactured in this way
A small amount of molten resin 5 is applied over the entire upper surface.

In this state, the lower surface is exposed to exhaust suction by a vacuum pump.

In such a case, the resin 5 and the soldering material invade the seal portion 4 and the ceramic body 3 accordingly.

After performing vacuum suction impregnation for a while, a sealed battery lid is obtained. This is integrated by welding to the top of the battery case containing the electrode plate group in the usual cell assembly process, and Alka I The liquid is injected through the liquid injection port, and the liquid injection port is also sealed by welding.

Fifty percent of the thus manufactured batteries of the present invention and conventional batteries were stored at 40'C for one year and tested for electrolyte leakage or twisting from the pole sections.

As a result, in the battery of the present invention, no electrolyte leakage or twisting was observed, whereas in the conventional battery, 5 leaks, or 10%, occurred.

In this way, according to the present invention, the brazing provided on the wall of the battery container has the sealed part impregnated with an alkali-resistant fluid by vacuum suction, so that not only the surface of the sealed part but also the inside of the sealed part is liquid-tight for a long period of time. This has the effect of producing an alkali I cell that has a significantly extended service life without electrolyte leakage.

[Brief explanation of drawings]

The drawing shows a cross-sectional view of the main parts of a battery lid equipped with a seal portion of the present invention. 1...Battery cover, 2...Pole pole, 3...
...Resin-impregnated ceramic body, 4...Resin-impregnated brazing part, a...Hermetic seal part, 5
...Fermented resin.

Claims (1)

[Claims] 1. A sealed alkaline storage battery whose brazing part on the battery container wall is impregnated with an alkaline-resistant fluid by vacuum suction.