JPH0727051U - Sealed storage battery - Google Patents

Abstract

(57) [Abstract] [Purpose] A sealed type storage battery that does not cause welding defects between the terminal cap and the flat plate of the rivet terminal even if the caulking amount of the rivet terminal is increased to improve the sealing performance. provide. [Structure] An electrode group is housed in a rectangular case body 4. The lid 5 that closes the opening of the case body 4 is provided with a terminal unit that also serves as a valve. The rivet-shaped terminal 20 of the terminal unit has a flat plate portion 20b at one end of a tubular portion 20a penetrating the lid body 5, and the other end of the tubular portion 20a is caulked to the back surface side of the lid body 5 to form an electrode plate. Caulking portion 20c electrically connected to the terminals of the group
Have. The flat plate portion 20b has a shape in which the dimension L1 in the long side direction in which the long side of the lid 5 extends is longer than the dimension L2 in the short side in which the short side of the lid 5 extends. The cross-sectional shape of the tubular portion 20a in the direction orthogonal to the axis is set such that the dimension L11 in the direction in which the long side of the lid 5 extends is longer than the dimension L22 in the direction in which the short side of the lid 5 extends.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sealed storage battery in which a plate group is housed in a flat battery case.

[0002]

[Prior art]

 3 (A) and 3 (B) are a partial sectional view of a terminal portion and a partial sectional view of an electrode plate group used in a conventional sealed alkaline storage battery as disclosed in Japanese Utility Model Laid-Open No. 62-1369. Shows. This sealed alkaline storage battery has a structure in which an electrode group 2 is housed in a prismatic sealed battery case 1 that also serves as a cathode, and a valve / terminal unit 3 is provided on the surface in the thickness direction of the battery case 1. Has become. The battery case 1 is composed of a case body 4 in the shape of a rectangular box with one end open, and a lid that closes the opening of the case body 4. The lid 5 is hermetically attached to the case body 4 by laser welding or the like. The electrode plate group 2 has a flat structure in which a plurality of plate-shaped anode plates 6 and cathode plates 7 are laminated via a separator 8. A rivet-type terminal 10 having a through hole forming a valve hole 9 is attached to the lid 5 via a seal packing 11. The rivet-shaped terminal 10 before use has a shape as shown in FIG. 3C, and has a flat plate portion 10b at one end of the tubular portion 10a. The rivet-type terminal 10 has a caulking portion 10c formed by inserting one end of a tubular portion 10a penetrating the lid body 5 into the through hole of the lid body 5 and then expanding the front end portion thereof. There is. The tubular portion 10a has a circular cross-section in the direction orthogonal to the axial direction. A washer-shaped lead member 12 is fitted between the crimped portion 10c and the seal packing 11, and the lead member 12 is connected to the anode output terminal of the electrode plate group 2. Further, a rubber valve body 13 is arranged on the flat plate portion 10b of the rivet-shaped terminal 10 so as to close the valve hole 9, and a terminal cap that also serves as a valve body retainer so as to press the rubber valve body 13. 14 is covered. The terminal cap 14 has a flange portion 14a, and the flange portion 14a is partially welded to the flat plate portion 10b of the rivet-type terminal 10. In order to improve the weldability of the terminal cap 14, the flat plate portion 10b has a shape in which the dimension in the long side direction in which the long side of the lid extends is longer than the dimension in the short side in which the short side of the lid extends. have. Specifically, the flat plate portion 10b has a shape in which both ends of a rectangle are rounded.

[0003]

[Problems to be solved by the device]

 When the length of the flat plate portion 10b is increased to improve the weldability of the terminal cap 14 as in the conventional storage battery, the caulking portion 10c of the rivet-type terminal 10 is used for the purpose of enhancing the sealability of the seal packing 11. When the caulking amount is increased, as shown in FIG. 3 (D), both end portions in the longitudinal direction of the flat plate portion 10b are lifted, and a welding failure occurs when the flange portion 14a of the terminal cap 14 is welded to the flat plate portion 10b. Is more likely to occur. Further, since both ends of the flat portion 10b are lifted, the terminal cap 14 is also lifted, which causes a problem that the height dimension of the storage battery is increased. Since such a problem occurs, conventionally, the caulking amount of the caulking portion 10c is suppressed within an appropriate range, so that the sealing performance of the seal packing 11 cannot be sufficiently enhanced.

An object of the present invention is to provide a sealed storage battery that does not cause welding defects between the terminal cap and the flat plate portion of the rivet terminal even if the caulking amount of the rivet terminal is increased to improve the sealing performance. To provide.

[0005]

[Means for Solving the Problems]

 The sealed storage battery to be improved by the present invention includes a battery case in which a lid is attached to an opening of a prismatic case body, an electrode plate group housed in the battery case, and a lid penetrating the battery. A rivet type in which one end of the tubular part has a flat plate part that constitutes the electrode part, and the other end of the tubular part is caulked to the back side of the lid and electrically connected to one output terminal of the electrode plate group. A terminal cap welded to the flat plate portion of the rivet-type terminal; and a valve body that is arranged so as to close one end of the tubular portion of the rivet-type terminal and is sandwiched between the flat plate portion and the terminal cap. ing. The flat plate portion of the rivet-shaped terminal has a shape in which the dimension in the long side direction in which the long side of the lid extends is longer than the dimension in the short side in which the short side of the lid extends.

In such a sealed type storage battery, in the present invention, the shape of the tubular portion of the rivet-shaped terminal has a cross-section in a direction orthogonal to the axis thereof as compared with the dimension in the direction in which the short side of the lid extends. The shape is such that the dimension in the direction in which the long side of the body extends is longer. Due to the formation of the caulked portion, the cross-sectional shape of this tubular portion must be such that cracks do not easily enter when the end of the tubular portion is expanded. If there are sharp bends or corners, it is difficult to crimp and cracks are likely to occur. Therefore, it is preferable to have a shape that does not have sharp bends or corners and is capable of crimping. Specifically, an oval shape (a shape in which both ends of a rectangle are rounded), an elliptical shape, or the like is preferable.

[0007]

[Action]

 As in the present invention, when the cross-sectional shape of the tubular portion of the rivet-shaped terminal is made such that the dimension in the direction in which the long side of the lid extends is longer than the dimension in the direction in which the short side of the lid extends, the tubular portion It is possible to shorten the distance from the boundary portion between the flat plate portion and the end portion in the long side direction of the flat plate portion. Therefore, in order to improve the sealing performance, even if the caulking amount is increased when forming the caulking portion, the end portion in the long side direction of the flat plate portion hardly rises. Therefore, it is possible to significantly reduce welding defects that occur when the terminal cap is welded to the flat plate portion.

[0008]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 (A) shows a cross-sectional view of the main part of the embodiment of the present invention, and FIG. 1 (B) shows a cross-sectional view taken along the line BB of FIG. 1 (A). C) shows a perspective view of the rivet-shaped terminal 20 before use. The flat plate portion 20b of the rivet-type terminal 20 used in this embodiment has an oblong outline shape in which both ends of a rectangle are rounded by hemispheres. As a result, the long sides 5a and 5b of the lid 5 extend. The length dimension L1 in the direction (long side direction) is longer than the length dimension L2 in the direction (short side direction) in which the short sides 5c and 5d of the lid 5 extend. The cross-sectional shape of the tubular portion 20a in the direction orthogonal to the axial direction is also oval like the contour shape of the flat plate portion 20b, and the length dimension L11 in the long side direction is the length dimension L22 in the short side direction. Is longer than. In accordance with this, the outlines of the collar portions 21a and 21b of the seal packing 21 are also oval.

The rubber valve body 23 is sandwiched by a fitting portion 23 a fitted into the valve hole 19 formed by the through hole of the tubular portion 20 a of the rivet-shaped terminal 20, the flat plate portion 20 b and the terminal cap 24. And a main body 23b. A cross-sectional view of the fitting portion 23a in a direction orthogonal to the axial direction is similar to the cross-sectional shape of the tubular portion 20a of the rivet-shaped terminal 20. The shape of the main body portion 23b may be any shape as long as it can be housed in the terminal cap 24 and can be deformed by an increase in internal pressure in the battery case.

The terminal cap 24 is composed of a dish-shaped portion 24b for accommodating the main body portion 23b of the rubber valve body 23, and a flange portion 24a that extends outward from the peripheral portion so as to surround the opening of the dish-shaped portion 24b. ing. The flange portion 24a of the terminal cap 24 is welded to the flat plate portion 20a of the rivet-type terminal 20 by an appropriate welding technique such as spot welding. This welding is performed so that a gas vent passage is formed between the flat plate portion 20a and the flange portion 24a.

Next, in order to confirm the effect of the present embodiment, a storage battery in which the cross-sectional shape of the tubular portion of the rivet-shaped terminal 20 in the direction orthogonal to the axial direction is circular as in the conventional case and other configurations are the same. We made a valve and terminal unit to measure the frequency of welding defects. FIG. 2 (A) shows the dimensions of each part of the valve / terminal unit of this embodiment used in the experiment, and FIG. 2 (B) shows the dimensions of each part of the conventional type valve / terminal unit. The unit is mm. In this experiment, the gap formed between the flat plate portion 20a of the rivet-type terminal 20 and the surface of the seal packing 21 when the caulking portion 20c is formed so that the compression force of the seal packing 21 becomes 0.4 MPa. The maximum size G and the number of occurrence of welding defects of the terminal cap were measured. As a result of making an experiment with 20 samples, the average value of the maximum gap size G is 0.11 mm in the structure of this embodiment shown in FIG. In the structure, the average value of the maximum gap size G is 0. It was found to be 42 mm. With a maximum gap size G, there was a four-fold difference between both structures. When the number of defective welding of the terminal caps was measured, 1 in 20 of the structures of FIG. 2 (A) had defective welding, but 8 of 20 in the structure of FIG. 2 (B). Welding failure occurred in each piece. Regarding the occurrence of welding defects, there was an 8-fold difference between the two structures.

From this experiment, even when the shape of the flat plate portion 20b of the rivet-shaped terminal 20 is increased in order to improve the weldability of the terminal gap, the long side of the cross-sectional shape of the tubular portion 20a as in the present embodiment. It has been found that by increasing the length in the direction, it is possible to prevent the flat plate portion 20a from rising and to suppress the occurrence of welding defects.

[0013]

[Effect of device]

 According to the present invention, since the cross-sectional shape of the tubular portion of the rivet-shaped terminal is such that the dimension in the direction in which the long side of the lid extends is longer than the dimension in the direction in which the short side of the lid extends. Even if the caulking amount is increased when forming the caulking part to improve performance, the long-side end of the flat plate part hardly lifts up, and occurs when the terminal cap is welded to the flat plate part. This has the advantage of significantly reducing welding defects.

[Brief description of drawings]

1A is a sectional view of a main part of an embodiment of the present invention, FIG. 1B is a sectional view taken along line BB of FIG. 1A, and FIG. Figure 5 shows a perspective view of the front rivet terminal.

FIG. 2A is a diagram showing the dimensions of each part of the valve / terminal unit of this embodiment used in the experiment, and FIG. 2B is a diagram showing the dimensions of each part of a conventional type valve / terminal unit. is there.

3A and 3B are a partial sectional view of a terminal portion and a partial sectional view of an electrode plate group used in a conventional sealed alkaline storage battery, and FIG. 3C is a conventional rivet. It is a perspective view of a shaped terminal, and (D) is a sectional view showing a state when a rivet-shaped terminal is strongly crimped.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery case 2 Electrode plate group 4 Case body 5 Lid body 10,20 Rivet type terminal 10a, 20a Cylindrical part 10b, 20b Flat plate part 10c, 20c Caulking part 11,21 Seal packing 12,22 Lead member 13,23 Rubber valve Body 14,24 Terminal cap

Claims (1)

[Scope of utility model registration request] 1. A battery case in which a lid is attached to an opening of a rectangular case body, an electrode plate group housed in the battery case, and an electrode at one end of a cylindrical portion penetrating the lid. A rivet-type terminal that has a flat plate portion that constitutes a portion and is crimped to the other end of the tubular portion on the back surface side of the lid body and electrically connected to one output terminal of the electrode plate group; A terminal cap to be welded to the flat plate portion of the terminal and a valve element that is arranged so as to close one end of the tubular portion of the rivet terminal and is sandwiched between the flat plate portion and the terminal cap. The flat plate portion of the rivet-shaped terminal has a shape in which a dimension in a long side direction in which a long side of the lid extends is longer than a dimension in a short side in which a short side of the lid extends. In the sealed storage battery, the tubular portion of the rivet-shaped terminal is Hermetically sealed battery, wherein a direction of the cross section perpendicular to the line have the the long side dimension than the dimension in the short side direction is longer shape.