JPH06104009A - Sealed secondary battery - Google Patents

Abstract

PURPOSE:To prevent leakage at a connecting part, and to provide a sealed secondary battery, which can extend life and improve reliability. CONSTITUTION:An alpha-alumina ring 2 is connected to the opening part of a solid electrolytic tube 1 by glass soldering, and a negative electrode lid 3 is connected to one surface of the alpha-alumina ring 2, while a positive electrode lid 4 is connected to the other surface of the ring 2. The connection is carried out by interposing an aluminium layer 12 containing silicon and at least one metal chosen from among manganese, copper, magnesium, and calcium. Since an aluminium layer of the connected part between the negative electrode lid 3 and the alpha-alumina ring 2 and aluminum of the connected part between the positive electrode lid 4 and the alpha-alumina ring 2 can be activated, airtightness can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealed secondary battery, and more particularly to a sealed secondary battery having a cathode chamber inside an ion conductive solid electrolyte tube and an anode chamber outside. It relates to the next 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 sodium is used in the anode chamber. There is a battery using sulfur as an anode active material.

A conventional structure of such a sealed type secondary battery will be described with reference to FIG. 3 and FIG.

That is, in the sealed secondary battery shown in FIG. 3, the α-alumina ring 2 is glass-soldered to the upper end of the solid electrolyte tube 1, and the cathode lid 3 is provided on the upper surface of the α-alumina ring 2.
However, the anode lid 4 is thermocompression bonded to the lower surface thereof, the cathode terminal 5 is welded to the cathode lid 3, and the cathode pipe 6 as a cathode current collector is welded through the central portion thereof. The lower part is inserted into the solid electrolyte tube 1 in which the metal fibers 7 are arranged, and the inside of the solid electrolyte tube 1 is evacuated from the cathode pipe 6 while keeping the temperature at about 150 ° C. 8 is vacuum-filled, and after filling, the upper end of the cathode terminal 5 is sealed to form a cathode chamber constituent body. This cathode chamber constituent body is inserted with a cylindrical sulfur molded body 10 and the anode current collecting terminal 11 is welded. It is inserted into a battery case 9 which also serves as an anode current collector, and its upper end is vacuum-welded to the anode lid 4.

On the other hand, the sealed secondary battery of FIG. 4 is the same as the sealed secondary battery of FIG. 3 except that the cathode lid 3 and the anode lid 4 are thermocompression bonded to the upper surface of the α-alumina ring 2. Is.

[0006]

In the sealed secondary battery having the above-described structure, the α-alumina ring 2 and the cathode lid 3 or the anode lid 4 are thermocompression bonded via high-purity aluminum, and aluminum is removed. α-alumina ring 2 and cathode lid 3
Alternatively, while being mutually diffused with the anode lid 4, a corrosion phase composed of aluminum, sodium, and silicon is formed in the joint portion by sodium as a cathode active material, sodium polysulfide as a reaction product, and silicon in the α-alumina ring. There is a problem that airtightness is generated and poor airtightness occurs.

As a method of suppressing the formation of the above-mentioned corrosion phase, it is possible to reduce the content rate of silicon. However, when the content rate of silicon is reduced, the surface activation performance of aluminum is deteriorated and the joint portion is deteriorated. There is a problem that the affinity is reduced and the airtightness is reduced.

[0008]

In order to solve the above-mentioned problems, the present invention comprises an α-alumina ring bonded to the opening of an ion conductive solid electrolyte tube, wherein one surface of the α-alumina ring is And a cathode chamber sealed with the cathode lid, and an anode chamber bonded with one side or the other side of the α-alumina ring and sealed with the anode lid. In the sealed secondary battery, the aluminum layer in which the cathode lid, the α-alumina ring and the anode lid and the α-alumina ring contain silicon and at least one metal selected from manganese, copper, magnesium and calcium. It is characterized by being joined by interposing.

[0009]

[Operation] The present invention relates to silicon and at least manganese, copper,
Since the cathode lid and the α-alumina ring and the anode lid and the α-alumina ring are joined with the aluminum layer containing one metal selected from magnesium and calcium interposed, a solid solution is formed in the aluminum. The manganese, copper, magnesium, and calcium that are contained in the aluminum activate the surface of aluminum to enhance the affinity of the joint.

[0010]

1 and 2 are sectional views of a sealed secondary battery according to the present invention. The same parts as those in FIGS. 3 and 4 are designated by the same reference numerals and the following description will be omitted.

The feature of the present invention is that, as shown in FIGS. 1 and 2, the cathode lid 3, the α-alumina ring 2 and the anode lid 4 are provided.
And α-alumina ring 2 is silicon and at least manganese,
The aluminum layer 12 containing one metal selected from copper, magnesium, and calcium is interposed and joined.

The aluminum layer 12 has a thickness of 0.2 to
2 mm, silicon content 10 to 100 PPM, manganese content 5000 PPM or less, copper content 30 to 1
5000PPM, magnesium content is 15000P
Below PM, the calcium content is 2 to 700 PPM,
Each aluminum layer is arranged between the cathode lid 3 and the α-alumina ring 2 and between the anode lid 4 and the α-alumina ring 2, and the temperature is about 600 to 625 ° C. and the pressure is about 1200 to 1.
The battery of the present invention was manufactured by holding at 600 kg / cm ² for 5 to 30 minutes and performing thermocompression bonding in air.

Ten cells of the battery of the present invention shown in FIGS. 1 and 2 were manufactured using the aluminum layer 12 containing each of the above-mentioned substances, and the airtightness was examined by the amount of helium leak. The results are shown in Table 1.

Table 1 compares airtightness between the battery of the present invention and the conventional battery when the content of silicon is 10 PPM and the content of copper is 30 PPM and the content of calcium is changed.

[0015]

[Table 1]

From Table 1, when the silicon content is 10 PPM and the copper content is 30 PPM, the airtightness can be increased and the silicon content can be increased if the calcium content is 2 to 700 PPM. 100PPM, copper content 15
000PPM, and manganese 5000PPM,
The same was true when magnesium was contained at 15,000 PPM. In addition, there was no difference between the batteries of FIGS. 1 and 2.

Table 2 compares the airtightness of the battery of the present invention with the conventional battery when the content of silicon is 10 PPM and the content of calcium is 2 PPM and the content of copper is changed.

[0018]

[Table 2]

From Table 2, when the silicon content is 10 PPM and the calcium content is 2 PPM, if the copper content is 30 to 15,000 PPM, the airtightness can be increased and the silicon content can be increased. 100PPM, calcium content 700PPM, and manganese 5000
The same was true when PPM and magnesium were contained at 15,000 PPM. In addition, there was no difference between the batteries of FIGS. 1 and 2.

Table 3 shows the airtightness between the battery of the present invention and the conventional battery when the content of magnesium is changed to 10 PPM, the content of calcium is 2 PPM, the content of copper is 30 PPM, and the content of magnesium is changed. It is a comparison.

[0021]

[Table 3]

From Table 3, the silicon content is 10 PPM, the calcium content is 2 PPM, and the copper content is 30 PPM.
In case of, magnesium content rate is 15000PP
If it is M or less, the airtightness can be enhanced, the content rate of silicon is 100 PPM, and the content rate of calcium is 700 PP.
The same was true when the M and copper contents were 15,000 PPM. In addition, there was no difference between the batteries of FIGS. 1 and 2.

Table 4 shows the airtightness between the battery of the present invention and the conventional battery when the content of manganese is varied with the content of silicon being 10 PPM, the content of calcium being 2 PPM and the content of copper being 30 PPM. It is a comparison.

[0024]

[Table 4]

From Table 4, silicon content is 10 PPM, calcium content is 2 PPM, and copper content is 30 PPM.
In this case, if the manganese content is 5000 PPM or less, the airtightness can be improved, the silicon content is 100 PPM, the calcium content is 700 PPM, the copper content is 15000 PPM, and the magnesium is 15000 PPM. It was the same even if it was contained. Also,
There was no difference between the batteries of FIGS. 1 and 2.

[0026]

As described above, according to the sealed secondary battery of the present invention, the aluminum layer at the joint between the cathode lid and the α-alumina ring and the aluminum layer at the joint between the anode lid and the α-alumina ring are used. Since the layer can be activated and the airtightness can be enhanced, the reliability and life of the sealed secondary battery can be improved.

[Brief description of drawings]

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

FIG. 2 is a cross-sectional view of a main part of a sealed secondary battery of the present invention.

FIG. 3 is a sectional view of a main part of a conventional sealed secondary battery.

FIG. 4 is a sectional view of a main part of a conventional sealed secondary battery.

[Explanation of symbols]

 1 Solid Electrolyte Tube 2 α-Alumina Ring 3 Cathode Lid 4 Anode Lid 12 Aluminum Layer

Claims (4)

[Claims] 1. A cathode which is formed by joining an α-alumina ring to an opening of an ion conductive solid electrolyte tube, a cathode lid being joined to one surface of the α-alumina ring, and a cathode which is sealed by the cathode lid. In a sealed secondary battery comprising a chamber and an anode chamber joined to one surface or the other surface of the α-alumina ring and sealed by the anode lid, the cathode lid and α- An alumina ring, an anode lid, and an α-alumina ring are joined together with an aluminum layer containing silicon and at least one metal selected from manganese, copper, magnesium, and calcium interposed therebetween. Secondary battery. 2. The sealed secondary battery according to claim 1, wherein the content of silicon is 10 to 100 PPM. 3. The content of silicon is 10 to 100 PPM, the content of manganese is 5000 PPM or less, the content of copper is 30 to 15,000 PPM, the content of magnesium is 15,000 PPM or less, and the content of calcium is 2 to 2.
The sealed secondary battery according to claim 1, wherein the sealed secondary battery is 700 PPM. 4. The cathode active material housed in the cathode chamber is sodium, the anode active material housed in the anode chamber is sulfur, and the ion conductive solid electrolyte tube is β-alumina or β ″ -alumina. The sealed secondary battery according to claim 1, wherein the sealed secondary battery is provided.