JPH06104008A - Sealed secondary battery - Google Patents

Abstract

PURPOSE:To provide sealed secondary battery, which can enhance the connection strength of a connection part, and 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 aluminum layer 12 containing silicon and at least one metal chosen from iron and nickel. Iron oxide and nickel oxide are formed on the connected part between the negative electrode lid 3 and the alpha-alumina ring 2, and on the connected part between the positive electrode lid 4 and the alpha-alumina ring 2, and the connection can thus be carried out under a good condition.

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 for suppressing the formation of the above-mentioned corrosion phase, it is conceivable to reduce the content rate of silicon, but if the content rate of silicon is reduced, there is a problem that the strength of the joint portion becomes small.

[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 consisting of, the cathode lid and α-alumina ring and the anode lid and α-alumina ring are silicon and at least iron,
It is characterized by being joined together with an aluminum layer containing one metal selected from nickel interposed.

[0009]

[Operation] In the present invention, the cathode lid, the α-alumina ring, the anode lid and the α lid are provided with the interposition of aluminum containing silicon and at least one metal selected from iron and nickel.
-Because it is joined with the alumina ring, iron oxide and nickel oxide are generated on the surface of aluminum by the iron and nickel in the aluminum at the time of thermocompression bonding in air,
It is possible to bond through the iron oxide and the nickel oxide.

[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 an α-alumina ring 2 are joined together with an aluminum layer 12 containing silicon and at least one metal selected from iron and nickel interposed.

The aluminum layer 12 has a thickness of 0.2 to
2 mm, silicon content 10 to 100 PPM, iron content 40 to 10000 PPM, nickel content 50
Each of the aluminum layers is arranged at a temperature of about 600 to 625 ° C. at a temperature of about 600 to 625 ° C. at a pressure of not more than 00 PPM and each aluminum layer is arranged between the cathode lid 3 and the α-alumina ring 2.
A battery of the present invention was manufactured by holding under a pressure of about 1200 to 1600 kg / cm ² for 5 to 30 minutes and thermocompression bonding in air.

5 from the battery of the present invention shown in FIGS. 1 and 2 using the aluminum layer 12 containing the above-mentioned substances.
Individual pieces were extracted and the tensile strength test was performed to compare the bonding strength between the α-alumina ring 2 and the cathode lid 3 and between the α-alumina ring 2 and the anode lid 4 with the conventional batteries of FIGS. 3 and 4.

Table 1 shows that the content of silicon is 40 PPM,
It shows the rate of increase in the bonding strength of the battery of the present invention with respect to the conventional battery when the iron content is 40 to 10000 PPM and the nickel content is 5000 PPM or less.

[0015]

[Table 1]

From Table 1, it can be seen that when the silicon content is 40 PPM, if the iron content is 40 to 8000 PPM and the nickel content is 3000 PPM or less, the rate of increase in bonding strength can be increased.

Table 2 shows the case where the rate of increase in bonding strength is the highest in Table 1, the iron content is 8000 PPM and the nickel content is 3000 PPM, and the silicon content is 3
It shows the rate of increase of the bonding strength of the battery of the present invention with respect to the conventional battery in the case of -100 PPM.

[0018]

[Table 2]

From Table 2, the iron content is 8000 PPM,
It can be seen that when the nickel content is 3000 PPM and the silicon content is 3 to 100 PPM, the rate of increase in bonding strength can be increased.

From Table 2, the iron content is 8000P.
It can be seen that if the PM and silicon contents are 100 PPM and the nickel content is 3000 PPM, the rate of increase in the bonding strength can be maximized. However, if the nickel content is reduced to 100 PPM under these conditions, the bonding strength increases. The rate was 35% in all cases, and it was found that even if the rate was further decreased to 0 PPM, it was unchanged.

From Table 2, the iron content is 8000P.
If the content ratio of PM and silicon is 3PPM and the content ratio of nickel is 3000PPM, the increase rate of the bonding strength is 8%. However, if the content ratio of nickel is reduced to 100PPM under these conditions, the increase of the bonding strength is increased. It was found that the rate further decreased, and under the conditions of Table 2, the silicon content rate was 10 to 100.
PPM is preferred.

Table 3 shows that the content of silicon is 40 PPM, the content of iron is 8000 PPM, and the content of nickel is 50 PPM.
2 shows the rate of increase in the bonding strength of the battery of the present invention with respect to the conventional battery when the value is 0 to 3000 PPM.

[0023]

[Table 3]

From Table 3, the iron content is 8000 PPM,
When the content rate of silicon is 40 PPM, it can be seen that if the content rate of nickel is 500 to 3000 PPM, the rate of increase in the bonding strength can be increased, and even if the content rate of nickel is reduced to 0%, it remains unchanged. Under the conditions of Table 3, the nickel content is preferably 3000 PPM or less.

Table 4 shows that the silicon content is 40 PPM, the nickel alloy content is 3000 PPM, and the iron content is 10.
It shows the rate of increase in the bonding strength of the battery of the present invention with respect to the conventional battery in the case of 0.00 to 8000 PPM.

[0026]

[Table 4]

From Table 4, the nickel content is 3000P.
When the PM and silicon contents are 40 PPM, if the iron content is 1000 to 8000 PPM, the rate of increase in bonding strength can be increased, and even if the iron content is reduced to 40 PPM, it may remain unchanged. Obviously, under the conditions shown in Table 4, the iron content is preferably 40 to 8000 PPM.

[0028]

As described above, according to the sealed secondary battery of the present invention, the iron oxide and the oxide are added to the joint between the cathode lid and the α-alumina ring and the joint between the anode lid and the α-alumina ring. Since nickel is generated and good bonding can be performed, 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. 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 chamber, wherein the cathode lid and α- The alumina ring and the anode lid and the α-alumina ring are silicon and at least iron,
A sealed secondary battery, which is joined with an aluminum layer containing one metal selected from nickel interposed therebetween. 2. The sealed secondary battery according to claim 1, wherein the content of silicon is 10 to 100 PPM. 3. The sealed form 2 according to claim 1, wherein the content of silicon is 10 to 100 PPM, the content of iron is 40 to 8000 PPM, and the content of nickel is 3,000 PPM or less. Next battery. 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.