JP2003288867A - Ceramic terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ceramic terminal for a storage battery capable of keeping a good airtightness at the inside of the storage battery by keeping a load enduring property of a terminal body against an external force and by effectively preventing the generation of crack on the ceramic base body. <P>SOLUTION: The ceramic terminal is composed of a bottomed cylinder-shaped or pole-shaped terminal body 3 made of Al alloy, inserted into and jointed to a cylinder-shaped ceramic base body 1 so as to protrude from both ends of the ceramic base body 1, having a flange part 3a at its lower end part; and a metal member 5, formed into approximately frame shape by forming an inner peripheral wall at the end part of the inner periphery, and an outer peripheral wall longer than the inner peripheral wall at the end part of the outer periphery respectively through whole peripheral part, inserted from the upper end part of the terminal body 3, to the outer peripheral surface of which, the inner peripheral wall is brazed, and the lower end part of the outer peripheral wall is brazed to the upper end part of the outer peripheral surface of the ceramic base body 1. The lower end part of the inner peripheral wall of the metal member 5 is made to contact with the upper surface of the ceramic body 1. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic terminal used as a terminal for a storage battery, which is attached to an electrolytic solution container such as a lithium ion battery to take out electricity.

[0002]

2. Description of the Related Art Conventionally, as shown in the cross-sectional view of FIG. 3, a ceramic terminal for a storage battery has a side portion joined by brazing or the like to a substantially circular opening of a container lid L of the storage battery so as to penetrate the inside and outside of the container. The through hole 21a is
₂ O ₃ ) Cylindrical ceramic base 21 made of ceramics or the like 21
It is equipped with. At the end of the through hole 21a of the ceramic base 21 on the outside of the container, a chamfered portion C is formed from the end surface of the ceramic base 21 on the outside of the container to the inner surface of the through hole 21a. Molybdenum (Mo) -manganese (M
A metallized layer 22a of n) or the like is applied.

[0003] A bottomed cylindrical terminal body made of an aluminum (Al) alloy, the bottom end of which is closed in the through hole 21a, the flange 23a is formed at the bottom end thereof, and the top end of which is open. 23 are inserted so that both ends thereof project from the ceramic base 21 and the flanges are locked to the lower surface of the ceramic base 21, and the metallized layer 22a and the terminal body 23 are interposed via the brazing material 24a containing aluminum as a main component. To be joined. Further, a metallized layer 22b formed in the central portion of the outer peripheral surface of the ceramic base 21 and an annular flange 25 made of a metal such as an Al alloy or an iron (Fe) -nickel (Ni) -cobalt (Co) alloy are provided. , The inside of the storage battery is hermetically sealed by joining through the brazing material 24b composed of a brazing material containing Al as a main component or a gold (approximately 37.5% by weight) -copper (approximately 62.5% by weight) brazing material. It

Further, inside the storage battery, the lower end surface of the terminal body 23 is connected to one electrode plate E of the storage battery, and the flange 25 is joined to the container lid L of the storage battery by welding, whereby one of the storage batteries Functioning as a terminal.

[0005]

However, in the above-mentioned conventional ceramic terminal, if the outer diameter of the terminal body 23 is increased in order to increase the current capacity, or if the hollow portion is eliminated to form a columnar shape, an Al alloy and a ceramic material are formed. Thermal expansion difference (alumina ceramics: 7 × 10 ^-6 / ° C, Al-Mn alloy: 23
(× 10 ⁻⁶ / ° C.), cracks are likely to occur at the outer peripheral end of the brazing portion of the ceramic base 21 due to the brazing material 24 a when the temperature of the brazing is lowered.

As a solution to this problem, a metallized layer 12a is formed on the upper end of the outer peripheral surface of the ceramic base 11 as shown in FIG. 2 so that a compressive stress, not a tensile stress, acts on the ceramic base when the brazing temperature is lowered. It is effective to use a substantially frame-shaped metal member 15 in which the inner peripheral end is brazed to the body 13 and the lower end of the outer peripheral wall is brazed to the metallized layer 12a.

However, when the metal member 15 is brazed in contact with the upper surface of the ceramic base 11, the terminal body 13
Due to vertical heat shrinkage during brazing and cooling of metal parts
15 is bound to the upper surface of the ceramic base 11. as a result,
When the outer peripheral wall of the metal member 15 contracts upward, there is a problem that cracks are generated in the ceramic base 11 from the brazed portion at the upper end of the outer peripheral surface of the ceramic base 11 upward.

Further, in FIG. 2, when the metal member 15 is brazed to the terminal body 13 so as not to come into contact with the upper surface of the ceramic substrate 11, the metal member 15 is plastically deformed by the load applied to the terminal body 13 from above. Resulting in. Worst case, metal member 15
There is a risk that cracking may occur in the brazed portion with the terminal body 13 due to the plastic deformation of, and poor airtightness may occur.

Therefore, the present invention has been completed in view of the above conventional problems, and an object thereof is to maintain the load bearing capacity of the terminal body against an external force and effectively prevent cracks from occurring in the ceramic substrate. By doing so, it is to provide a ceramic terminal for a storage battery, which can improve the airtightness inside the storage battery.

[0010]

A ceramic terminal according to the present invention is a cylindrical ceramic base body and an aluminum body which is inserted and joined to the ceramic base body so as to project from both ends of the ceramic base body and has a collar portion formed at a lower end thereof. A bottomed cylindrical or columnar terminal body made of an alloy, and an inner peripheral wall projecting downward at the inner peripheral end is formed over the entire circumference, and an outer peripheral wall longer than the inner peripheral wall projecting downward at the outer peripheral end is formed over the entire circumference. And is inserted from the upper end of the terminal body, the inner peripheral wall is brazed to the outer peripheral surface of the terminal body, and the lower end of the outer peripheral wall is brazed to the upper end of the outer peripheral surface of the ceramic base. And a lower end of the inner peripheral wall of the metal member is in contact with an upper surface of the ceramic base.

The ceramic terminal of the present invention, having the above-mentioned structure, can maintain the load resistance against external force of the terminal body and effectively prevent cracks in the ceramic base body, thus providing good airtightness inside the storage battery. can do. As a result, the performance of the storage battery is stable for a long period of time, and long life and high reliability are obtained.

In the ceramic terminal of the present invention, preferably, the metal member has a thickness of 0.8 to 1.5 mm, a vertical length of the inner peripheral wall of 0.5 to 4 mm, and a vertical direction of the inner peripheral wall and the outer peripheral wall. Is 2 to 5 mm, and the width between the inner peripheral edge and the outer peripheral edge is 1.2 to 9.5 mm.

With the above structure, the ceramic terminal of the present invention can more effectively prevent the occurrence of cracks in the ceramic substrate, and can further improve the airtightness inside the storage battery. As a result, the performance of the storage battery is stable for a long period of time, and long life and high reliability are obtained.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The ceramic terminal of the present invention will be described in detail below. FIG. 1 is a sectional view showing an example of an embodiment of a ceramic terminal of the present invention. In FIG. 1, 1 is a cylindrical ceramic substrate, 3 is a terminal body made of Al alloy, 5 is a metal member made of Al alloy, and 6 is a metal flange. The terminal body 3 and the metal member 5 are joined via the brazing material 4a, and the metallized layers 2a and 2b, the metal member 5 and the flange 6 are brazing materials 4b and 4c, respectively.
A ceramic terminal that hermetically seals the inside of the storage battery is configured by being bonded via the.

The ceramic substrate 1 has a cylindrical shape or a polygonal cylindrical shape made of ceramics such as alumina ceramics or the like having excellent electric insulation, and the terminal body 3 and the flange 6 are electrically insulated. keeping. Then, as shown in FIG. 1, the ceramic base 1 has side portions thereof joined to a substantially circular opening of the container lid L, and a through hole 1a penetrating the inside and the outside is formed at a substantially central portion thereof. Into the through hole 1a, the terminal body 3 is inserted and joined so that the upper end of the terminal body 3 on the outer side of the container protrudes, and the flange 3a formed on the lower end of the terminal body 3 on the inner side of the container is attached. The lower surface of the ceramic base 1 is brought into contact with and locked. Also,
A flange 6 is joined to the outer peripheral surface of the ceramic base 1,
It is joined and fixed to the container lid L via the flange 6. The flange portion 3a is provided so as to be flush with the lower end surface of the terminal body 3, but it is sufficient that it projects from the side surface of the lower end portion of the terminal body 3, and is not necessarily flush with the lower end surface of the terminal body 3. It doesn't have to be.

When such a ceramic substrate 1 is made of, for example, alumina ceramics, raw materials such as aluminum oxide (alumina: Al ₂ O ₃ ), silicon oxide (SiO ₂ ), calcium oxide (CaO), magnesium oxide (MgO), etc. Raw material powder prepared by adding a suitable organic binder to the powder, while filling the press mold of a predetermined shape,
It is manufactured by pressing this at a predetermined pressure and molding, and then calcining the obtained molded body in the atmosphere at a temperature of about 1600 ° C.

Further, the ceramic base 1 has a step portion for arranging the brazing material formed at the upper end of the outer peripheral surface thereof, and an annular metallization layer 2a is applied so as to extend from the step portion to the outer peripheral surface. There is. This metallized layer 2a is made of Mo
A base metal for joining the metal member 5 to the ceramic substrate 1, which is made of a metallized layer such as -Mn. The metal member 5 is joined to the metallized layer 2a via a brazing material 4b containing Al as a main component. It This metallized layer 2a is
For example, a metal paste obtained by adding and mixing an appropriate organic binder and a solvent to Mo powder and Mn powder and a metal oxide powder is applied from the stepped portion of the ceramic substrate 1 to the outer peripheral surface by a brush coating method or the like, and this is applied. By baking at a temperature of about 1400 ° C. in a reducing atmosphere, the ceramic substrate 1 is deposited from the step portion to the outer peripheral surface.

Further, a metallized layer 2b is formed on a part of the outer peripheral surface of the ceramic substrate 1 (center portion or lower portion in FIG. 1).
And the metallized layer 2b is composed of a metallized layer such as Mo—Mn similar to the metallized layer 2a.
A base metal for joining the flange 6 to the ceramic substrate 1, and the metallized layer 2b has a brazing material containing Al as a main component and gold (about 37.5% by weight) -copper (about 62.5% by weight).
It is joined via a brazing material 4c such as a brazing material. For the metallized layer 2b, similar to the metallized layer 2a, for example, a metal paste obtained by adding and mixing an appropriate organic binder and solvent to Mo powder, Mn powder, and metal oxide powder is used as a part of the outer peripheral surface of the ceramic substrate 1. It is applied to the outer peripheral surface of the ceramic substrate 1 by applying it by a brush coating method or the like and baking it at a temperature of about 1400 ° C. in a reducing atmosphere.

The surfaces of the metallized layers 2a, 2b are prevented from being oxidized and corroded by the metallized layers 2a, 2b and are improved in wettability with the brazing materials 4b, 4c. In order to prevent the bondability from being deteriorated by peeling, cracks, etc. due to the stress generated after the joining, the brazing material 4 has excellent corrosion resistance such as Ni.
It is preferable to deposit a metal having excellent wettability with b and 4c to a thickness of about 1 to 10 μm.

The terminal body 3, which is inserted into the through hole 1a of the ceramic substrate 1 and joined thereto, is a conductive path and is immersed in the electrolytic solution contained in the container of the storage battery. Because it needs to be stable,
It is made of an Al alloy having excellent corrosion resistance, preferably an Al alloy having excellent corrosion resistance and easy to braze (JIS H 4040 alloy No. 3003).

The terminal body 3 has a columnar shape such as a substantially columnar shape having a flange portion 3a formed at the lower end thereof, and a convex portion or the like may be provided on the upper surface for connection with an external conductor. Further, in order to reduce the stress due to the brazing on the outer peripheral surface of the ceramic base body 1, it is possible to form a bottomed cylindrical shape in which a hollow portion is formed downward from a substantially central portion of the upper surface of the terminal body 3.

Like the terminal body 3, the metal member 5 inserted into the terminal body 3 from the upper end and joined to the outer peripheral surface thereof is immersed in the electrolytic solution contained in the container of the storage battery, so that the metal member 5 is in a high electromotive force state. Since it is necessary to be electrochemically stable, it is composed of an Al alloy having excellent corrosion resistance, preferably an Al alloy having excellent corrosion resistance and easy to braze (JIS H 4040
Alloy No. 3003).

The metal member 5 has a substantially frame shape in which an inner peripheral wall protruding downward at the inner peripheral end is formed over the entire circumference, and an outer peripheral wall longer than the inner peripheral wall protruding downward at the outer peripheral end is formed over the entire circumference. , The inner peripheral wall is brazed to the outer peripheral surface of the terminal body 3 while being inserted from the upper end of the terminal body 3, the lower end of the outer peripheral wall is brazed to the upper end of the outer peripheral surface of the ceramic base 1, and the lower end of the inner peripheral wall is ceramic. It is in contact with the upper surface of the base 1. The metal member 5 preferably has a thickness of 0.8 to 1.5 m.
When the vertical length of the inner peripheral wall is 0.5 to 4 mm, the vertical length difference between the inner peripheral wall and the outer peripheral wall is 2 to 5 mm, and the width between the inner peripheral edge and the outer peripheral edge is 1.2 to 9.5 mm. Be good.

If the thickness of the metal member 5 is smaller than 0.8 mm, the Si component in the Al brazing material may diffuse and the periphery of the brazing portion may be melted due to the lower melting point. Also, 1.5
If the thickness is larger than mm, the stress on the outer peripheral surface of the ceramic substrate 1 due to thermal contraction during temperature reduction after brazing cannot be alleviated, and it becomes difficult to prevent cracking of the ceramic substrate 1.

Further, if the difference in length between the inner peripheral wall and the outer peripheral wall in the vertical direction is less than 2 mm, the joint length of the outer peripheral wall becomes short and the airtightness is apt to occur. Also,
When it is larger than 5 mm, the brazing material does not easily flow to the lower end of the outer peripheral wall, a uniform fillet of brazing material cannot be formed on the lower end of the outer peripheral wall, and cracks are likely to occur in the ceramic substrate 1 due to local stress concentration.

The inner wall has a vertical length of 0.5 mm.
When it is less than the lower limit, the lower main surface of the metal member 5 comes into contact with the upper surface of the ceramic base 1 due to the deformation during the temperature rise after brazing and the thermal contraction during the temperature decrease after brazing, and the metal member 5 is constrained and the ceramic base 5 is restrained. The tensile stress in the upward direction may act on the outer peripheral surface of No. 1 to cause cracks. On the other hand, if it is larger than 4 mm, thermal contraction of the outer peripheral wall becomes large when the temperature is lowered after brazing, and cracks are likely to occur on the outer peripheral surface of the ceramic substrate 1.

The width between the inner peripheral edge and the outer peripheral edge of the metal member 5 is
If it is less than 1.2 mm, the brazing material flows in between them, and the stress relaxation effect due to the compositional deformation of the metal member 5 is reduced, so that cracks are generated in the brazed portion on the outer peripheral surface of the ceramic substrate 1, which is unsuitable. When it exceeds mm, the heat shrinkage becomes large, so that the ceramic substrate 1
Is not suitable since the stress on the outer peripheral surface of the ceramic base becomes large and cracks are likely to occur on the outer peripheral surface of the ceramic substrate 1.

The brazing materials 4a and 4b are composed mainly of Al and have an Al--Si composition. A
Since the l-alloy has a bad brazing property because of its strong oxide film on the surface, magnesium (M) having a gettering action to remove the oxide film on the Al alloy surface and improve the brazing property is used.
It consists of a brazing material containing a small amount of g). In order to improve the flowability of the brazing material at the time of brazing, it is necessary that the brazing material contacts the terminal body 3 and the ceramic base 1, and the terminal body 3 and the metal member 5, respectively, over substantially the entire circumference.
It is preferable that a wire-shaped brazing material that is more likely to come into contact with a curved surface be wound in advance and brazed than a plate-shaped preform formed by a pressing method or the like is used.

The brazing material 4c is composed of a material containing Al as a main component or a brazing material containing gold (about 37.5% by weight) -copper (about 62.5% by weight) as a component. Since the brazing material needs to contact almost the entire circumference, wire-shaped brazing material that is easier to contact the curved surface than the plate-shaped preform formed by pressing etc. is pre-wound and brazed. It is preferable.

The method for manufacturing the ceramic terminal of the present invention will be described below.

When the terminal body 3 made of an Al alloy is bonded to the metallized layer 2a via the metal member 5 and the brazing materials 4a and 4b, the terminal body 3 is penetrated through the ceramic substrate 1 so that the upper end portion thereof projects. After being inserted into the hole 1a, the metal member 5 in which the wire-shaped Al brazing material is fitted in advance on the inner surface of the outer peripheral wall is attached to the terminal body 3 and the ceramic base 1, and the metal member 5 is attached.
The inner peripheral wall is inserted until it contacts the upper surface of the ceramic substrate 1. Then, the wire-shaped Al brazing material is arranged so as to be wound around the outer peripheral surface of the terminal body 3 so as to come into contact with the upper surface of the metal member 5. Thereafter, these Al brazing materials are heated at a temperature of about 600 ° C. in a vacuum atmosphere to be melted to braze the terminal body 3 and the metal member 5, and the metal member 5 and the metallized layer 2a. Join by. Then, the electrode plate E of the storage battery is attached to the lower end surface of the terminal body 3.
By connecting with, it functions as a ceramic terminal for electrically connecting the electrode plate E to the outside.

The flange 6 joined to the outer peripheral surface of the ceramic substrate 1 is a metal annular body made of an Al alloy, Fe-Ni-Co alloy, or the like. Brazing material 4c whose main component is
Are joined through. Then, by welding the flange 6 to the container lid L of the storage battery, the ceramic terminal of the present invention is fixed to the storage battery container.

In order to bond the flange 6 to the metallized layer 2b via the brazing material 4c, the ceramic base 1 is inserted inside the flange 6 and the wire-shaped brazing material is brought into contact with the metallized layer 2b and the flange 6. 4c is arranged so as to be wound around the metallized layer 2b, and this Al brazing material is heated at a temperature of about 600 ° C. in a vacuum atmosphere and melted, so that the flange 6 and the metallized layer 2b are brazed together To do.

As described above, the ceramic terminal of the present invention is
The terminal body 3 is inserted into the through hole 1a of the ceramic base body 1 so as to project from both ends of the ceramic base body 1, the metal member 5 is inserted into the terminal body 3, and the side surface of the terminal body 3 and the inner peripheral wall of the metal member 5, and It is manufactured by brazing and joining the outer peripheral wall of the metal member 5 and the outer peripheral surface of the ceramic base 1, and brazing the flange 6 to the outer peripheral surface of the ceramic base 1.

Further, by connecting the lower end surface of the terminal body 3 of the ceramic terminal to the electrode plate E and welding the flange 6 to the container lid L, the inside of the storage battery is kept airtight and the inside and outside of the storage battery are separated from each other. It functions as an electrically connected storage battery.

Thus, according to the present invention, when the metal member 5, the terminal body 3 and the ceramic substrate 1 are brazed and joined together,
It is possible to effectively alleviate the stress applied to the ceramic substrate 1 by the thermal contraction of the metal member 5 during the temperature reduction after brazing, and as a result, it is possible to effectively prevent the ceramic substrate 1 from cracking after brazing.

[0037]

EXAMPLES Examples of the present invention will be described below.

First, as a conventional ceramic terminal, as shown in FIG.
The structure described above was manufactured as follows. Consisting of a sintered body of aluminum oxide (Al ₂ O ₃ ) having a purity of 93% by weight,
A cylindrical ceramic substrate 11 having an outer diameter of 17 mm, an inner diameter of 11 mm and a height of 12 mm, and having a step portion with a diameter of 14.8 mm and a height of 1.5 mm on the outer peripheral surface was prepared. The surface of the stepped portion excluding the area of 0.5 mm from the upper surface of the ceramic base 11, the surface of the outer peripheral surface continuing from the stepped portion in the range of 3.5 mm in the height direction, and the height of the central portion of the outer peripheral surface of the ceramic base 11. 89% by weight of Mo, Mn
6% by weight and SiO ₂ at 5% by weight, a metal paste was applied by printing to a thickness of 10 μm, dried, and then baked at a temperature of 1400 ° C. in a humidified forming gas. Thus, a strip-shaped M is formed on a part of the step portion of the ceramic base 11, from the step portion to the outer peripheral surface, and on the central portion of the outer peripheral side surface.
Metallized layers 12a and 12b made of o-Mn alloy were deposited. Then, a Ni plating layer was deposited on the metallized layers 12a and 12b by electrolytic plating to a thickness of about 2 μm.

Next, in the through hole 11a of the ceramic substrate 11,
The outer diameter is 11 mm and the height is 20 mm.
alloy A3003 having a flange 13a with a height of 2 mm and a height of 2 mm
Was inserted into the terminal body 13. Then, the outer diameter is 19 mm, the inner diameter is 11 mm, the outer peripheral wall has a wall thickness of 1 mm, and the height (length in the vertical direction) is 3.5 mm. Al alloy A3003 (98.7% by weight)
A metal member 15 made of Al-1.3 wt% Mn) was prepared.

Next, a ring-shaped member having a diameter slightly larger than the inner diameter of the outer peripheral wall of the metal member 15 is used.
BA4003 (90 wt% Al-
7.5 wt% Si-2.5 wt% Mg) was pressed into the inner circumference of the outer peripheral wall of the metal member 15. The metal member 15 from the upper end to the terminal body
The metal member 15 was inserted until the outer peripheral wall of the metal member 15 was in contact with the upper end of the outer peripheral surface of the ceramic base 11 and the lower main surface was in contact with the upper surface of the ceramic base 11. Then, in advance, the terminal body 13
BA4003, which is an Al-Si alloy brazing material with a diameter of 1 mm, which was made into a ring shape with a diameter slightly smaller than the outer diameter of
It was arranged so as to contact the side surface of the terminal body 13 and the upper surface of the metal member 15.

Further, a ring shape having a diameter slightly smaller than the outer diameter of the ceramic base 11 is previously formed, and the diameter A is 1 mm.
BA4003, which is an l-Si alloy brazing material, is placed on the metallized layer 14b on the outer peripheral surface of the ceramic base 11. Then, on the outer peripheral surface of the ceramic base 11, an inner diameter of 17 mm and an outer diameter of 27
mm, wall thickness 1 mm, height 3 mm, a flange 16 made of A3003 is inserted and brought into contact with the brazing material.

Then, these were housed in a carbon jig and heated to 600 ° C. in a vacuum furnace to bond them. As a result, Sample 1 was manufactured.

Next, in the structure of FIG. 1, the thickness (thickness) of the metal member 5, the difference in vertical length between the inner peripheral wall and the outer peripheral wall (step), and the height of the inner peripheral wall (upper and lower) (Length in the direction), and the width between the inner peripheral edge and the outer peripheral edge were variously changed as shown in Table 1, and Samples 2 to 27 were produced in the same manner as in the above-mentioned conventional example. In Samples 21 to 27, the ceramic base 1
The inner diameter was 11 mm, and the wall thickness condition of the ceramic was changed by changing the outer dimensions.

The airtightness of these samples 1 to 27 was confirmed with a helium leak detector, and the leak amount was 1.3 × 10
^-10 Pa · m ³ / sec. The following were accepted.
After that, the Al alloy and the brazing material are melted with caustic soda,
After the metallized layer was dissolved in aqua regia, the penetrant flaw detection liquid was applied to the brazed portion and wiped off, and it was observed with a magnifying glass whether or not cracks were generated in the ceramic substrate 1. The results are shown in Table 1.

A metallized layer 4a was formed on the outer peripheral surface of the ceramic base 1 extending from the stepped portion in the same size as the height of the outer peripheral wall of the metal member 5.

[0046]

[Table 1]

From Table 1, in Sample 1 having the conventional structure, the ceramic substrate is cracked, and the thickness of the metal member 5, the step between the inner peripheral wall and the outer peripheral wall, the height of the inner peripheral wall, the inner peripheral end and the outer periphery. Whereas in Samples 2, 4, 8, 12, 12, 14 to 17, 20, 22, and 26 in which any of the widths between the edges is outside the scope of the present invention, poor airtightness and cracks in the ceramic substrate occurred. hand,
It was found that in all of the products of the present invention, the ceramic substrate did not crack and the airtightness was also good.

The present invention is not limited to the above-described embodiments and examples, and various modifications may be made without departing from the scope of the present invention.

[0049]

The ceramic terminal of the present invention is a bottomed cylinder made of a cylindrical ceramic base and an aluminum alloy which is inserted and joined to the ceramic base so as to project from both ends of the ceramic base and has a flange at the lower end. -Shaped or columnar terminal body, and an inner peripheral wall projecting downward at the inner peripheral end is formed over the entire circumference, and an outer peripheral wall longer than the inner peripheral wall projecting downward at the outer peripheral end is formed over the entire circumference. A metal member which is inserted from the upper end of the terminal body and whose inner peripheral wall is brazed to the outer peripheral surface of the terminal body and whose lower end is brazed to the upper end of the outer peripheral surface of the ceramic base. Since the lower end of the inner peripheral wall of the member is in contact with the upper surface of the ceramic base, the load bearing capacity of the terminal body against external force can be maintained, and the ceramic base can be effectively prevented from cracking. Airtightness parts can be made good. As a result, the performance of the storage battery is stable for a long period of time, and long life and high reliability are obtained.

The ceramic terminal of the present invention is preferably
The metal member has a thickness of 0.8 to 1.5 mm, a vertical length of the inner peripheral wall of 0.5 to 4 mm, and a vertical length difference between the inner peripheral wall and the outer peripheral wall of 2 to 5 mm. Since the width between the edge and the outer peripheral edge is 1.2 to 9.5 mm,
It is possible to more effectively prevent the occurrence of cracks in the ceramic substrate, and further improve the airtightness inside the storage battery. As a result, the performance of the storage battery is stable for a long period of time, and long life and high reliability are obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an embodiment of a ceramic terminal of the present invention.

FIG. 2 is a sectional view showing an example of a conventional ceramic terminal.

FIG. 3 is a sectional view showing another example of a conventional ceramic terminal.

[Explanation of symbols]

1: Ceramic substrate 2a, 2b: Metallized layer 3: Terminal body 3a: collar part 4a-4c: brazing material 5: Metal member

Claims (2)

[Claims] 1. A bottomed cylindrical or columnar terminal made of a cylindrical ceramic base and an aluminum alloy which is inserted and joined to the ceramic base so as to project from both ends of the ceramic base and has a flange at the lower end. The terminal body has a substantially frame shape in which an inner peripheral wall protruding downward at the inner peripheral end is formed over the entire circumference, and an outer peripheral wall longer than the inner peripheral wall protruding downward at the outer peripheral end is formed over the entire circumference. A metal member that is inserted from the upper end of the terminal body and the inner peripheral wall is brazed to the outer peripheral surface of the terminal body, and the lower end of the outer peripheral wall is brazed to the upper end of the outer peripheral surface of the ceramic base, A ceramic terminal, wherein a lower end of the inner peripheral wall of the metal member is in contact with an upper surface of the ceramic base. 2. The metal member has a thickness of 0.8 to 1.5 mm, a vertical length of the inner peripheral wall of 0.5 to 4 mm, and a vertical length difference between the inner peripheral wall and the outer peripheral wall of 2 to 2. The ceramic terminal according to claim 1, wherein the width between the inner peripheral edge and the outer peripheral edge is 5 mm and is 1.2 to 9.5 mm.