JPS6282667A - Sodium-sulfur battery - Google Patents

Abstract

PURPOSE:To prevent breakage of battery caused in battery assembly or high temperature operation by pressing the inner circumference of circular cathode conductive material with a circular metal member, and filling molten-sulfur resistant material powder between the inner bottom of a container and the lower part of a solid electrolyte tube. CONSTITUTION:The inner circumference of a circular cathode conductive material 11 is pressed with a circular metal member 13. Molten-sulfur resistant material powder or particle or their mixture 14 is filled between the inner bottom 5' of the inside of the circular metal member 13 and the lower end 1' of a solid electrolyte tube 1. Thereby, shock in battery assembly is absorbed by the powder, particles, or the mixture 14. In high temperature operation, the cathode conductive material 11 expands in a central direction and the metal member 13 is pressed in a central direction and the solid electrolyte tube 1 is supported by the mixture 14. Thereby, breakage of the battery caused in battery assembly or high temperature operation can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to sodium-sulfur batteries, and more particularly to support structures for solid electrolyte tubes.

Prior art and its problems In a sodium-sulfur battery, sodium as a cathode active material and sulfur as an anode active material are separated in a battery case by a sodium ion conductive solid electrolyte tube such as r-alumina. It is a completely sealed secondary battery that operates at a temperature of .degree. C. to 350.degree. C., and has a structure as shown in the cross-sectional view of FIG. In FIG. 2, reference numeral 1 denotes a solid electrolyte tube in which a cathode chamber is formed and an α-alumina ring 2 is bonded to the upper end of the solid electrolyte tube.

Also, 3 is a cathode lid, 4 is an anode lid, and α-alumina ring 2
The anode lid 4 is bonded to the upper and lower surfaces by heat and pressure, respectively.
A battery case 5 is welded to the peripheral edge of the tube 1, and an anode chamber is formed in the gap between the battery case 5 and the solid electrolyte tube 1. In the cathode chamber described above, sodium as a cathode active material 7 held by metal fibers 6 is arranged, and in the anode chamber, sulfur as an anode active material 9 impregnated into an anode conductive material 8 made of graphite felt is arranged. and vacuum sealed.

In the sodium-sulfur battery having the above structure, the load of the solid electrolyte tube 1 is applied to the glass solder joint, so a disk-shaped support member 10 made of molten sulfur resistant material such as α-alumina is arranged at the inner bottom of the battery case 5. Although the lower end of the solid electrolyte tube 1 is supported, the battery has the disadvantage that the battery can be damaged due to impact during battery assembly or lateral displacement during high-temperature operation.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned drawbacks, and provides a sodium-sulfur battery that will not be damaged by preventing impact during battery assembly and lateral displacement during high-temperature operation from affecting the solid electrolyte tube. The purpose is to

Structure of the Invention In the sodium-sulfur battery of the present invention, an annular anode conductive material is brought into contact with the inner peripheral surface of the lower part of the battery case, and an annular metal member is pressed against the inner peripheral surface of the anode conductive material. Powder or granules of a molten sulfur-resistant substance, or a mixture thereof, is filled between the inside bottom of the tank and the lower end of the solid electrolyte tube.

EXAMPLES The present invention will be explained below using examples. FIG. 1 is a sectional view of essential parts of the sodium-sulfur battery of the present invention, and parts having the same functions as those in FIG. 2 are designated by the same reference numerals. In Figure 1, the annular anode conductive material in contact with [i] in the lower part of the battery case is 11, and the third electrode impregnated with sulfur is inserted from the bottom of the battery case made of chromium-diffused stainless steel with an inner diameter of 68 fins. A 7-item felt ring 12 with an inner diameter of 43 m5, an outer diameter of 70 m, and a thickness of 3 mm is interposed between the members 8. The annular anode conductive material 11 is made by impregnating graphite felt with sulfur, which is divided into two vertically and having a width of about 10 fins in the horizontal direction, and compression molding it to a width of about 5 mm, and an inner diameter of 56 fins. , has an outer diameter of 66fi, a longitudinal thickness of 8mm, and its inner peripheral surface is pressed by an annular metal member 15 with a lateral width of Q and 5wn. Further, the battery case 5 inside the annular metal member 16
The molten sulfur-resistant substance powder or granules or a mixture thereof filled between the inner bottom surface 5' and the lower end 1' of the solid electrolyte tube 1 is 14, and α-alumina with a particle size of 8 μm to 300 μm is It is densely packed.

With the above configuration, the impact during battery assembly is alleviated by the powder or granules of the molten sulfur resistant material, or a mixture thereof 14, and during high temperature operation, the annular @pole 1i
The solid electrolyte tube 1 is supported by the powder or granules of the molten sulfur-resistant material or the mixture 14 of the solid electrolyte tube 1 .

Ten batteries each of the present invention having the above configuration and a conventional battery as shown in FIG.
When the damage state of the battery was investigated by applying 3G vibration in the horizontal direction at °C, 3 out of 10 cells in the conventional battery were damaged at the glass solder joint, whereas in the battery of the present invention, the damage occurred at the glass solder joint. Effects of the Invention As detailed in the embodiments, the sodium-sulfur battery of the present invention has a structure in which the annular anode conductive material that is brought into contact with the inner peripheral surface of the lower part of the m-cell moves toward the center during high-temperature operation. The solid electrolyte tube is supported by expanding and pressing a powder or granules of molten sulfur-resistant material, or a mixture thereof through an annular metal member, and the impact is cushioned by the powder, granules, or a mixture thereof during battery assembly. This prevents battery damage during battery assembly and high-temperature operation.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a main part of the sodium-sulfur battery of the present invention, and FIG. 2 is a cross-sectional view of a conventional sodium-sulfur battery. 1... Solid m solute tube 5... vLmlo...
Disc-shaped support member 11... Annular anode IT conductor 13
... Ring-shaped metal member 14 ... Powder or granules of molten sulfur-resistant material or mixture thereof

Claims (2)

[Claims] (1) In a sodium-sulfur battery whose anode chamber is the gap between a battery case and a sodium ion-conducting solid electrolyte tube housed in the battery case, a ring-shaped anode conductive material is placed on the inner peripheral surface of the bottom of the battery case. The inner peripheral surface of the anode conductive material is pressed by the annular metal member, and powder or powder of a molten sulfur-resistant substance is placed between the inner bottom surface of the battery case inside the annular metal member and the lower end of the solid electrolyte tube. 1. A sodium-sulfur battery, characterized in that it is filled with sodium sulfur or a mixture thereof. (2) The sodium-sulfur battery according to claim 1, wherein the annular anode conductive material is impregnated with an anode active material and compressed in the lateral direction.