JPH0582164A - Manufacture of sealed secondary battery - Google Patents

Abstract

PURPOSE:To improve the productivity of a sealed secondary battery. CONSTITUTION:An anode cover 3 and cathode cover 4 are formed by joining a metal material comprizing aluminum alloy, iron alloy, nickel alloy, and a clad steel plate or plated steel material to an upper surfaces of an alpha-alumina ring having inclined parts 21, 22 on the inner side and the outer side of the upper surface under a temperature of 400 deg.C or less by ultrasonic waves, and joining at least one layer of a metal material of the same sort or a differnt sort on it under a temperature of 400 deg.C or less by ultrasonic waves. 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. In addition, the anode cover and the cathode cover can be joined to the alpha-alumina ring surely by the plural layers of the metal materials.

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 cover and an anode cover made of a plurality of layers of metal material to the upper surface of the alumina ring to form a cathode chamber and an anode chamber closed by the cathode cover and the anode cover, respectively. A method of manufacturing a sealed secondary battery, wherein the α-alumina ring is provided with an inclined portion inside and outside the upper surface, and the inclined portion is made of an aluminum alloy, an iron alloy, a nickel alloy, a clad steel material, or plated. After a metal material made of steel is ultrasonically bonded at a temperature of 400 ° C. or lower, a metal material of the same kind or a different kind is ultrasonically bonded thereon at least one layer at a temperature of 400 ° C. or lower to form a cathode lid and an anode. It is characterized in that it constitutes a lid.

[0008]

Therefore, according to the present invention, a metal material made of an aluminum alloy, an iron alloy, a nickel alloy, a clad steel material or a plated steel material is ultrasonically bonded at a temperature of 400 ° C. or lower, and then the same or different metal Since the materials are bonded by ultrasonic waves in at least one layer at a temperature of 400 ° C. or less, it is possible to prevent stress due to thermal cycle 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.

A feature of the present invention is that a step of glass-bonding the α-alumina ring 2 to the upper part of the solid electrolyte tube 1 and a plurality of layers of metal material on the upper surface of the α-alumina ring 2 by ultrasonic wave in the atmosphere. And a step of forming the cathode lid 3 and the anode lid 4 by bonding the inclined lids 21 and 22 inside and outside the upper surface of the α-alumina ring 2.
Is provided, the cathode lid 3 is formed on the inner inclined portion 21, and the anode lid 4 is formed on the outer inclined portion 22. Although two layers of nickel-plated iron are used as the metal material, the number of layers is not limited. Further, the joining is performed by ultrasonic vibration (frequency: 35 kHz, torsional rotation amplitude: about 35 μm, in a torsional rotation direction perpendicular to the surface of the metal material).
The pressure is about 1.7 kg / cm ² and the time is 3 seconds, but ultrasonic vibration in the circumferential direction (frequency: 40 kHz, amplitude: about 40 μm) is applied to the surface of the metal material.
m, pressure: about 1.5 Kg / cm ² , time: 1 second). The torsional rotation amplitude may be 2 μm to 100 μm, preferably 2 μm to 100 μm.
It is preferably 5 μm to 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.

As the metal material, aluminum alloy, iron alloy, clad steel material, plated steel material other than nickel-plated iron may be used, or different kinds of metals may be combined. In this case, α-alumina ring 2
It is possible to ensure the joining by lowering the melting point of the metal material to be joined to the lower than the melting point of the metal to be joined thereon.

Next, 10 batteries were manufactured by the manufacturing method of the present invention in which the cathode lid 3 and the anode lid 4 were formed by ultrasonic waves in the vertical twist rotation direction, and the conventional manufacturing method as shown in FIG. A heat cycle test from room temperature to 350 ° C. was carried out on 10 batteries, and the number of damaged batteries was investigated. 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. Also, the ultrasonic bonding can be reliably performed by the inclined portion. Furthermore, since the cathode lid and the anode lid are formed by joining a plurality of layers of metal materials to the inclined portion, the cathode lid and the anode lid can be joined securely to the α-alumina ring.

[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 21 Inclined Part 22 Inclined Part

Claims (5)

[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 cover and an anode cover made of a plurality of layers of metal material to the upper surface of the alumina ring to form a cathode chamber and an anode chamber closed by the cathode cover and the anode cover, respectively. A method of manufacturing a sealed secondary battery, wherein the α-alumina ring is provided with an inclined portion inside and outside the upper surface, and the inclined portion is made of an aluminum alloy, an iron alloy, a nickel alloy, a clad steel material, or plated. After a metal material made of steel is ultrasonically bonded at a temperature of 400 ° C. or lower, a metal material of the same kind or a different kind is ultrasonically bonded thereon at least one layer at a temperature of 400 ° C. or lower to form a cathode lid and an anode. A method of manufacturing a sealed secondary battery, which comprises forming a lid. 2. The hermetically sealed secondary according to claim 1, wherein the metal material, the α-alumina ring, and the metal materials are joined together by ultrasonic waves in a direction of torsional rotation perpendicular to the surface of the metal material. Battery manufacturing method. 3. The sealed secondary battery according to claim 1, wherein the metal material, the α-alumina ring, and the metal materials are bonded to each other by ultrasonic waves in a circumferential direction on the surface of the metal material. Manufacturing method. 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. 5. The manufacture of a sealed secondary battery according to claim 1, wherein the melting point of the metal material to be joined to the α-alumina ring is lower than the melting point of the metal material to be joined thereon. Method.