JPH0582163A - Manufacture of sealed secondary battery - Google Patents

Abstract

PURPOSE:To improve the productivity of a sealed secondary battery. CONSTITUTION:An anode cover 3 and a cathode cover 4 comprising aluminum alloy, iron alloy, nickel alloy, and a clad steel plate or plated steel material are joined to an upper surface of an alpha-alumina ring 2 having inclined parts 21, 22 on the inner side and outer side of the upper surface and having metal brazing material fused at least in the inclined parts under a temperature of 400 deg.C or less by ultrasonic waves respectively. A battery can thus be manufactured without a stress by a heat cycle given to a glass solder joined part of a solid electrolyte tube with the alpha-alumina ring, so the productivity can be improved. Joining by the ultrasonic waves can be secured by the inclined parts and the metal brazing material fused at least in the inclined parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sealed secondary battery, and more specifically, it comprises a cathode chamber inside an ion conductive solid electrolyte tube and an anode chamber outside. The present invention relates to a method for manufacturing a sealed secondary battery.

[0002]

2. Description of the Related Art As a sealed secondary battery in which a cathode chamber is formed inside an ion conductive solid electrolyte tube and an anode chamber is formed outside, sodium as a cathode active material is placed in the cathode chamber and There is a battery using sulfur as an anode active material.

A conventional method for manufacturing such a sealed type secondary battery will be described with reference to FIG. 2 which is a sectional view of an essential portion of a sodium-sulfur battery.

That is, in FIG. 2, the solid electrolyte tube 1
The α-alumina ring 2 is glass-soldered on the upper part of the
The anode lids 4 are respectively thermocompression bonded to the lower surface. A cathode terminal 5 is welded to the cathode lid 3, a cathode pipe 6 serving as a cathode current collector is welded through the central portion thereof, and the lower portion thereof is inserted into the solid electrolyte tube 1. Metal fibers 7 are arranged in the solid electrolyte tube 1, and the inside of the solid electrolyte tube 1 is evacuated from the cathode pipe 6 while keeping the temperature at about 150 ° C. Then, sodium 8 melted at the same temperature is vacuum filled. After filling, the upper end of the cathode terminal 5 is sealed. In such a cathode chamber structure, a cylindrical sulfur molded body 10 is inserted, and the anode current collector terminal 11 is welded and inserted into a battery case 9 which also functions as an anode current collector. 4 is vacuum welded and completely sealed.

[0005]

In the above-described method for manufacturing a sealed secondary battery, the α-alumina ring 2 has an upper surface to which the cathode lid 3 and a lower surface to which the anode lid 4 is attached by thermocompression bonding.
There was a problem that the glass solder joint between the alumina ring 2 and the solid electrolyte tube 1 was cracked and the solid electrolyte tube 1 was damaged when the battery was used.

Further, in the method of manufacturing such a sealed type secondary battery, there is a problem that the solid electrolyte tube 1 is cracked due to the thermal cycle during the process and the solid electrolyte tube 1 is damaged during use of the battery. It was

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides an α-type solid electrolyte tube at the upper part of an ion conductive solid electrolyte tube.
-A step of bonding an alumina ring to glass solder, and
-Bonding a cathode lid and an anode lid to the upper surface of the alumina ring to form a cathode chamber sealed by the cathode lid and an anode chamber sealed by the anode lid, and manufacturing a sealed secondary battery. A method in which the α-alumina ring is provided with inclined portions on the inner and outer sides of the upper surface, and a metal brazing material is fused to at least the inclined portions. Is made of an aluminum alloy, an iron alloy, a nickel alloy, a clad steel material or a plated steel material, and the cathode lid and the anode lid are ultrasonically bonded to the α-alumina ring at a temperature of 400 ° C. or less. is there.

[0008]

Therefore, according to the present invention, the cathode lid and the anode lid made of an aluminum alloy, an iron alloy, a nickel alloy, a clad steel material or a plated steel material are fused at a temperature of 400.degree. -Because it is ultrasonically bonded to the alumina ring, it is possible to prevent stress due to thermal cycles from being applied to the glass solder bonding portion.

Further, it is possible to prevent the solid electrolyte tube from cracking due to the thermal cycle.

[0010]

1 is a cross-sectional view of a main portion of a sodium-sulfur battery as a sealed secondary battery obtained by the manufacturing method of the present invention, in which the same parts as those in FIG.

The present invention is characterized by the step of glass-bonding the α-alumina ring 2 to the upper portion of the solid electrolyte tube 1, and the cathode lid 3 and the anode made of nickel-plated iron on the upper surface of the α-alumina ring 2. A step of joining the lid 4 by ultrasonic waves in the atmosphere, wherein the α-
Inclined portions 2 inside and outside the upper surface of the alumina ring 2
1, 22 are provided, the metal brazing material 12 is fused to at least this inclined portion, and the cathode lid 3 is attached to the inner inclined portion 21.
The anode lid 4 is joined to the outer inclined portion 22. In addition, the above-mentioned joining is performed by ultrasonic vibration (frequency: 35 kHz) in a torsional rotation direction perpendicular to the surfaces of the cathode lid 3 and the anode lid 4.
z, torsional rotation amplitude: about 35 μm, pressure: about 1.7 kg /
cm ² and time: 3 seconds), but ultrasonic vibration (frequency: 40 kHz, amplitude: about 40 μm, pressure: about 1) in the circumferential direction with respect to the surfaces of the cathode lid 3 and the anode lid 4 is performed. 0.5 Kg / cm ² , time: 1 second). The torsional rotation amplitude may be 2 μm to 100 μm, preferably 25 μm.
It is preferable that the thickness is ˜50 μm.

A cathode terminal 5 is welded to the cathode lid 3, a cathode pipe 6 as a cathode current collector is welded through the central portion thereof, and the lower portion thereof is inserted into the solid electrolyte tube 1. A cathode chamber assembly is formed similar to the battery of FIG.

In this cathode chamber structure, a cylindrical sulfur former 10 is inserted, and an anode current collector terminal 11 is inserted into a welded battery case 9 which also serves as an anode current collector, and its upper end is It is vacuum-welded to the anode lid 4 and completely sealed.

Although the ultrasonic bonding is performed in the atmosphere, in a battery operated at a high temperature such as a sodium-sulfur battery, the operating temperature is 400 ° C. or lower, preferably 300 ° C. It may be carried out at a temperature of ˜380 ° C.

Further, as the cathode lid 3 and the anode lid 4,
In addition to nickel-plated iron, aluminum alloy, iron alloy, clad steel material, and plated steel material may be used.

Next, ten batteries manufactured by the manufacturing method of the present invention, which are bonded by applying ultrasonic vibrations in the direction of vertical twist rotation to the surfaces of the cathode lid 3 and the anode lid 4, and the conventional battery as shown in FIG. A heat cycle test from room temperature to 350 ° C. was carried out on 10 batteries manufactured by the manufacturing method of 1. and the number of damaged batteries was investigated, and the results shown in Table 1 were obtained.

[0017]

[Table 1]

It can be seen from Table 1 that in the battery prepared by the conventional method, 2 cells were damaged at the 10th cycle, whereas in the battery prepared by the method of the present invention, only 1 cell was damaged at the 15th cycle.

A similar test was carried out when the surfaces of the cathode lid 3 and the anode lid 4 were bonded by applying ultrasonic vibration in the circumferential direction, and the same results as in Table 1 were obtained.

Further, when the same test was performed in the case where ultrasonic vibration was applied at a temperature of 350 ° C. and the bonding was performed, the same results as in Table 1 were obtained.

[0021]

As described above, according to the method of manufacturing a sealed secondary battery of the present invention, stress due to thermal cycle is not applied to the glass solder joint between the solid electrolyte tube and the α-alumina ring. The productivity of can be improved. Further, ultrasonic bonding can be surely performed by the inclined portion and at least the metal brazing material fused to the inclined portion.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a sealed secondary battery manufactured by a manufacturing method of the present invention.

FIG. 2 is a cross-sectional view of a main part of a sealed secondary battery manufactured by a conventional manufacturing method.

[Explanation of symbols]

 1 Solid Electrolyte Tube 2 α-Alumina Ring 3 Cathode Lid 4 Anode Lid 12 Metal Brazing Material 21 Inclined Part 22 Inclined Part

Claims (4)

[Claims] 1. An α-ion is formed on the top of an ion-conducting solid electrolyte tube.
-A step of bonding an alumina ring to glass solder, and
-Bonding a cathode lid and an anode lid to the upper surface of the alumina ring to form a cathode chamber sealed by the cathode lid and an anode chamber sealed by the anode lid, and manufacturing a sealed secondary battery. A method in which the α-alumina ring is provided with inclined portions on the inner and outer sides of the upper surface, and a metal brazing material is fused to at least the inclined portions. Is made of an aluminum alloy, an iron alloy, a nickel alloy, a clad steel material or a plated steel material, and the cathode lid and the anode lid are ultrasonically bonded to the α-alumina ring at a temperature of 400 ° C. or less. Manufacturing method of secondary battery. 2. The hermetically sealed structure according to claim 1, wherein the cathode lid, the anode lid and the α-alumina ring are joined by ultrasonic waves in a direction of vertical twist rotation with respect to the surfaces of the cathode lid and the anode lid. Type secondary battery manufacturing method. 3. The closed type according to claim 1, wherein the cathode lid, the anode lid and the α-alumina ring are joined to the surfaces of the cathode lid and the anode lid by ultrasonic waves in the circumferential direction. Manufacturing method of secondary battery. 4. A β-ion as a solid electrolyte tube having ion conductivity, which has a step of storing sodium as a cathode active material in a cathode chamber and a step of storing sulfur as an anode active material in an anode chamber. The method for manufacturing a sealed secondary battery according to claim 1, further comprising a step of glass-bonding an α-alumina ring on top of alumina or β ″ -alumina.