JP2003045406A - Sealed battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealed battery suppressed in the total height by lowering the output terminal in a battery using a hermetic sealing plate formed by insulating by fixing the output terminal to a sealing plate with glass, and increased in capacity. SOLUTION: A positive terminal 4 has an upper flat surface 4a to facilitate connection of a positive electrode connection lead 10 by providing a flange part 14 on the outer exposed side; and a lower flat surface 4b on the side positioning inside a battery can 1 to facilitate connection of a positive electrode lead 6. The total height of the battery is suppressed by the positive terminal 4 structure having a T-shaped cross section, and the amount of a power generating element 2 is increased to increase the battery capacity. A projection part 11 is formed in the flange part 14, and this prevents generation of cracks caused by adhesion of glass 5 to the flange part 14 when the positive terminal 4 is hermetic-sealed with glass 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealed battery in which a battery can containing a power generating element is completely sealed from the outside air so that stable energy can be taken out for a long period of time.

[0002]

2. Description of the Related Art A lithium thionyl chloride battery is known as a battery capable of obtaining a stable output voltage over a relatively long period of time. The thionyl chloride used as a reactant in this battery decomposes in the air, so a completely sealed structure that shields it from the outside air is adopted to enable stable use over a long period of time. In a battery having a completely sealed structure such as this lithium thionyl chloride battery, generally, the positive electrode terminal is insulated and fixed to the negative electrode by a glass hermetic seal to improve airtightness.

FIG. 4 is a cross-sectional view showing a conventional structure of a sealed battery, in which a power generating element 32 is housed in a battery can 31 formed in a cylindrical shape with a bottom and insulated by an upper insulating ring 38 and a lower insulating ring 39. The open end of the battery can 31 is sealed by the hermetic sealing plate 33. In the hermetic sealing plate 33, a positive electrode terminal 34 is provided by penetrating into the battery can 31 at an opening opened at the center of the sealing plate 33a, and by filling the opening 40 with glass 40, the positive electrode terminal 34 is closed. Insulation is fixed to. Hermetic sealing plate 33
Is welded to the open end of the battery can 31, and the resin 42 is filled in the recess on the outer surface side, so that the inside of the battery can 31 has a completely sealed structure that is shielded from the outside air.

In this battery, the positive electrode lead 34 connected to the positive electrode of the power generating element 32 is welded to the positive electrode terminal 34 protruding into the battery can 31, and the negative electrode of the power generating element 32 is connected to the battery can 31 to form the battery can. 31 constitutes a negative electrode terminal. Since the positive electrode terminal 34 protruding to the outside is cylindrical, the positive electrode connecting lead 41 is wound and connected to the positive electrode terminal 34 by welding. The cylindrical positive electrode terminal 34 is used to inject the electrolytic solution into the battery can 31 through the cylindrical cylinder after sealing the battery can 31 with the hermetic sealing plate 33. After the injection, the inner cylinder is closed by the sealing plug 35.

[0005]

As shown in the above-mentioned conventional structure, in the glass hermetic seal, the positive electrode terminal 34 is formed in a rod shape so that it can be insulated and fixed by the glass 40, and penetrates the sealing plate 33a to inside the battery can 31. So that the lead connection can be made between the inside of the battery can 31 and the external connection. If such a rod-shaped positive electrode terminal 34 projects into the battery can 31 and the outside, the overall height of the battery becomes large, and not only is the space for accommodating the battery wasted, but also the power generating element 32 in the battery can 31. However, there is a problem in that the storage space is restricted and the battery capacity is reduced.

Further, it is not easy to connect a lead to the rod-shaped positive electrode terminal 34, and particularly, since the positive electrode connection lead 41 is often connected to the positive electrode terminal 34 by a user, the connection work is easier. Is desired. That is, since the battery can 31 also serves as the negative electrode terminal of the battery, the negative electrode connection is generally made on the bottom surface of the battery can 31 and can be welded to a flat surface, which facilitates the connection work, and the positive electrode is also welded on the flat surface. The desired structure is desirable.

The object of the present invention is to improve the volume efficiency by shortening the length of the output terminal attached to the hermetically sealed plate by the glass seal, and at the same time, to provide a sealed battery having a structure for facilitating the terminal connection. To provide.

[0008]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a hermetic sealing in which an opening of a battery can accommodating a power generating element is insulated and fixed with glass by an output terminal penetrating the opening in a sealing plate. In the sealed battery which is sealed by a plate, the output terminal has a flat surface on which an lead connected to an electrode plate is welded at an end located inside the battery can, and a flange is provided at an end exposed to the outside. It is formed in a T-shaped cross section having a flat surface for welding a lead for external connection, and a protrusion projecting toward the glass is formed on the inner surface side of the flange. And

In the sealed battery according to the present invention, the output terminal attached to the hermetic sealing plate is formed in a T-shaped cross section, and the lead for connecting to the electrode plate is welded to the flat surface in the battery can and externally connected. Externally connected leads can be welded to a wide flat surface with a flange on the exposed part, so not only is lead processing easy, but also the height of the output terminal can be made small, reducing the overall height of the battery. Since the protruding height into the battery can is reduced, it is possible to increase the storage volume of the power generation element and increase the battery capacity.

When the hermetic sealing plate is formed by using the output terminal having the T-shaped cross section as described above, if the output terminal is insulated and fixed to the sealing plate by the molten glass, the glass is solidified on the flange of the output terminal when the glass is solidified. If adhered, cracks may occur due to the difference in stress during solidification, but since the protrusion is provided on the inner surface side of the flange, the glass does not advance beyond the protrusion due to its surface tension, It is possible to carry out hermetic sealing by the output terminal provided with.

It is preferable that the protrusion has a ring-shaped protrusion having a triangular cross section, and the glass cannot move into the recess formed by the protrusion due to the surface tension of the glass, and the glass is stopped at the tip of the protrusion. It is possible to prevent the occurrence of cracks during solidification without contacting the flange.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention.
The embodiments described below are examples of embodying the present invention and do not limit the technical scope of the present invention.

FIG. 1 shows a structure of a sealed battery according to an embodiment, in which a power generating element 2 is insulated by an upper insulating ring 8 and a lower insulating ring 9 in a battery can 1 having a cylindrical shape with a bottom. And the open end of the battery can 1 is sealed by a hermetic sealing plate 3. The hermetic sealing plate 3
Insulates and fixes the positive electrode terminal (output terminal) 4 formed in a T-shaped cross section in the opening formed in the center of the sealing plate 3a with glass 5, and the peripheral portion of the sealing plate 3a and the opening of the battery can 1. The battery can 1 is sealed by laser welding the ends.

The hermetic sealing plate 3 is formed on the carbon jig 12 as shown in FIG.
The positive electrode terminal 4, the glass pellets 5a, and the sealing plate 3a as shown in (c) are positioned and arranged, and the glass pellets 5a are melted by passing them through a high temperature furnace. It is manufactured in a state where the positive electrode terminal 4 is insulated and fixed.

The positive electrode terminal 4 is, as shown in FIG.
As its material, ferritic stainless steel (SUS44
4), tantalum, titanium or the like is used to form the flange portion 14 on one end side, and the lower flat surface 4 is formed on the side located inside the battery can 1.
On the side where b is exposed to the outside, a large upper flat surface 4a including the flange portion 14 is formed. Also, the flange portion 1
A protrusion 11 having a triangular cross section is formed on the lower surface of 4 in a ring shape.

The sealing plate 3a is a nickel-plated steel plate or austenitic stainless steel (SUS304).
L), and as shown in FIG. 3C, an opening 16 for hermetically sealing the positive electrode terminal 4 is formed, and the periphery of the opening 16 is a plate surface to increase the adhesion area with the glass 5. Is drawn. In addition, the peripheral edge portion of the battery can 1 that fits into the open end has a plate surface drawn to increase the welding area with the battery can 1 and increase the strength.

The glass 5 used for glass hermetically sealing the positive electrode terminal 4 to the sealing plate 3a is made of SiO ₂
· To B a ₂ O ₃ · SrO mainly ASF700 or ASF20 composed mainly of _{SiO 2 · B 2 O 3 ·} BaO
0 is preferable, as shown in FIG.
2a, the carbon jig 12 is disposed between the positive electrode terminal 4 and the sealing plate 3a as shown in FIG.

When the positive electrode terminal 4 penetrating the sealing plate 3a is hermetically sealed by the glass 5 as described above, when the positive electrode terminal 4 is provided with the flange portion 14, the glass 5 is melted and the positive electrode terminal 4 and When it adheres to the sealing plate 3a and is solidified by cooling, as shown in FIG. 2B, it adheres to the part sandwiched between the positive electrode terminal 4 and the sealing plate 3a, the positive electrode terminal 4 and the flange portion 14 thereof. A stress difference occurs between the parts and the parts during solidification, and cracks 13 may occur at the boundary between the parts, as shown in the figure, and the hermeticity of the glass hermetic seal is impaired. The generation of the crack 13 is a problem that can occur when the positive electrode terminal 4 having the T-shaped cross section is used by providing the flange portion 14.
In order to solve this, the positive electrode terminal 4 has a protrusion 11 formed on the inner surface of the flange 14 toward the glass 5.

Since the protrusion 11 is provided, as shown in FIG. 2A, when the positive electrode terminal 4 is arranged on the carbon jig 12 and the glass 5 is placed thereon, the glass 5 is formed. Is arranged so as not to contact the flange portion 14 by the protrusion portion 11. When the glass 5 is melted in this state, the glass 5 does not flow down below the protrusion 11 due to its surface tension, and when it solidifies, the glass 5 does not come into contact with the flange 14 as shown in FIG. 1B. Therefore, there is no fear that the crack 13 will occur.

As shown in FIG. 1A, the lower flat surface 4b of the positive electrode terminal 4, which is insulated and fixed to the hermetic sealing plate 3 formed as described above, is formed from the positive electrode plate which constitutes the power generating element 2. The positive electrode lead 6 pulled out of the upper insulating ring 8 is welded and joined, and the hermetic sealing plate 3 is used for the battery can 1
Is attached to the open end of the battery can 1 and the periphery of the sealing plate 3a and the inner wall of the open end of the battery can 1 are laser-welded to hermetically seal the inside of the battery can 1. Since the positive electrode lead 6 can be joined to the positive electrode terminal 4 by welding to the lower flat surface 4b of the positive electrode terminal 4, it is not necessary to project the positive electrode terminal 4 into the battery can 1, and the power generation to be housed in the battery can 1 can be performed. The capacity of the element 2 can be increased to increase the battery capacity. Compared with the sealed battery having the conventional structure shown in FIG. 4, the sealed battery according to the present embodiment has an AA size (diameter 14 mm, total height 4 mm).
In the case of a 9.5 mm) cylindrical manganese dioxide lithium battery, a capacity increase of about 10% was realized.

Further, the externally exposed portion of the positive electrode terminal 4 has the flange portion 14 formed therein, so that the upper flat surface 4 having a large bonding area which facilitates the bonding of the positive electrode connecting lead 10.
a is formed. Since the joining of the positive electrode connecting lead 10 to the battery is often done by the user's hand, it is desired that the work can be carried out easily and surely.
Welding is difficult when lead-bonding to a conventional round bar, but since welding is performed on a flat surface, general welding equipment can be used for easy welding. In addition, there is no useless protrusion on the battery, and the total height of the battery can be reduced.

As shown in FIG. 1A, the recess formed in the upper part of the hermetic sealing plate 3 is filled with a resin 15 to enhance hermeticity. As the resin 15, a two-component epoxy compound resin or the like can be applied.

[0023]

As described above, according to the present invention, when the positive electrode terminal is insulated and fixed to the sealing plate by the glass hermetic seal, the positive electrode terminal formed in the T-shaped cross section having the upper and lower flat surfaces is used. Since the amount of protrusion of the positive electrode terminal to the outside of the battery is reduced, the total height of the battery is suppressed, and by reducing the amount of protrusion to the inside of the battery, the capacity of the power generation element is increased and the battery capacity is increased. You can Further, since both the battery internal connection and the battery external connection to the positive electrode terminal can be performed on a flat surface, lead bonding can be performed easily and reliably. When glass hermetic sealing is performed using such a positive electrode terminal having a T-shaped cross section, the risk of cracks in the glass can be prevented by the protrusion provided on the flange portion of the positive electrode terminal.

[Brief description of drawings]

FIG. 1 shows a structure of a sealed battery according to an embodiment (a).
Is a sectional view, (b) is a partially enlarged sectional view.

2A is a cross-sectional view showing a method for manufacturing a hermetic sealing plate, and FIG. 2B is a cross-sectional view illustrating the occurrence of cracks.

FIG. 3 (a) is a positive electrode terminal, (b) is a glass pellet,
FIG. 6C is a perspective view showing each configuration of the sealing plate.

FIG. 4 is a cross-sectional view showing a configuration of a sealed battery according to a conventional technique.

[Explanation of symbols]

1 battery can 2 power generation elements 3 Hermetic sealing plate 3a Seal plate 4 Positive terminal (output terminal) 4a Upper flat surface 4b Lower flat surface 5 glass 11 protrusion 14 Flange

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takeshi Inui             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Takayuki Tanahashi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 5H011 AA03 AA17 EE04 FF04 GG01                       HH09 KK01                 5H022 AA09 CC02 CC08 CC16                 5H024 AA12 CC02 CC14 DD11 FF12                       FF31 HH15

Claims (2)

[Claims] 1. A hermetic seal formed by closing an opening of a battery can having a bottomed cylindrical shape and accommodating a power generation element by a hermetic sealing plate having an output terminal penetrating the sealing plate insulated and fixed by glass. In the battery, the output terminal is formed with a flat surface on which an lead connected to an electrode plate is welded at an end located inside the battery can, and a flange is provided at an end exposed to the outside to provide a lead for external connection. A sealed battery, which is formed in a T-shaped cross section having a flat surface for welding and has a protrusion protruding toward the glass on the inner surface side of the flange. 2. The sealed battery according to claim 1, wherein the protrusion has a ring-shaped protrusion having a triangular cross section.