JPH0714552U - Square sealed battery - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent the welded part of the metal sealing plug from protruding from the outer side surface of the bottomed square outer can in a square sealed battery. This makes it possible to reduce the battery storage space of the device. [Structure] An electrolyte injection hole (2) is formed on a side surface of a bottomed rectangular outer can (1) which also serves as a unipolar terminal. The liquid injection hole is hermetically sealed by a metal sealing plug (3). The bottomed rectangular outer can is formed with a concave peripheral portion of the liquid injection hole.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rectangular sealed battery as a power source for driving a portable device, and more particularly to a battery storage space when it is mounted on a device.

[0002]

[Prior art]

 In recent years, large currents and large outputs are required for batteries as power sources, such as laptop computers, portable information devices such as word processors, camera-integrated VTRs, AV devices such as LCD TVs, mobile communication devices such as mobile phones, etc. There is a wide variety of developing devices and there is a demand for batteries with higher energy density.

At present, the cylindrical type, which is widely used as a sealed battery, has a circular portion in its cross section, and therefore, when mounted in a device, there is a lot of waste in the storage portion in terms of volume. From the viewpoint of effectively utilizing a small space, it is preferable to use a prismatic sealed battery.

On the other hand, in the rectangular sealed battery, a method of welding a metal sealing lid plate to a metal bottomed rectangular opening having a built-in power generation element by using a laser beam has a high productivity and reliability. It has been confirmed as the best performance in terms of points.

In general, a rectangular sealed battery is manufactured by stacking a strip-shaped positive electrode plate and a negative electrode plate with a separator interposed therebetween, and taking out the positive electrode lead and the negative electrode lead that are previously attached to the sealing lid plate from the positive electrode plate and the negative electrode plate. Welded to a lead and integrated as an electrode group, and the electrode group is gradually inserted into the bottomed rectangular outer can where the electrolyte is injected so that the electrolyte does not jump out of the opening of the bottomed rectangular outer can. To insert. After the insertion, the bottomed rectangular outer can and the sealing cover plate are laser-welded.

However, in the rectangular sealed battery, when the bottomed rectangular outer can and the lid plate are laser-welded after the electrolytic solution is injected, if the electrolytic solution adheres to the welded portion, welding failure occurs. And the liquid leaks from that part.

Further, in the process of inserting the electrode group integrated with the sealing lid plate into the bottomed rectangular outer can, if the insertion is faster than the impregnation speed of the electrolytic solution into the electrode, the bottomed rectangular The electrolyte is pushed out of the outer can. Therefore, this method has a limit in terms of productivity improvement.

In view of the above problems, therefore, a method has been adopted in which a liquid injection hole is provided on the side surface of the bottomed rectangular outer can and the electrolytic solution is injected from the liquid injection hole. That is, the bottomed rectangular outer can having the built-in power generation element and the battery lid are laser-welded, and the electrolytic solution is injected through the injection hole. Then, a metal sealing plug is pressed against the liquid injection hole, and its head is welded to be integrated with the bottomed rectangular outer can and hermetically sealed.

[0009]

[Problems to be solved by the device]

 However, if the welded part of the sealing plug protrudes from the outer side surface of the bottomed square outer can and is mounted on a portable device, the space for accommodating the battery must also consider the protruding part, and the device can be made smaller. However, there is a problem in obtaining a battery in which the welded portion of the metal sealing plug does not protrude from the outer side surface of the bottomed rectangular outer can.

[0010]

[Means for Solving the Problems]

 The present invention solves the above-mentioned problems by forming a liquid injection hole provided on the side surface of a bottomed rectangular outer can that also serves as a one-polarity terminal having a built-in power generation element and its peripheral portion into a concave shape.

[0011]

[Action]

 According to the battery of the present invention, the liquid injection hole and the peripheral portion provided on the side surface of the bottomed rectangular outer can are made concave so that the liquid injection hole is sealed by the metal sealing plug, and the metal sealing plug is welded. The part does not protrude from the outer side surface of the bottomed square outer can.

[0012]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a top view and a side sectional view of an essential part of a rectangular sealed battery according to the present invention. In FIG. 1, reference numeral 1 denotes a bottomed rectangular outer can that also serves as a negative electrode terminal and is a power generating element (not shown). ) Is built in. Reference numeral 2 denotes a liquid injection hole provided on the side surface of the bottomed rectangular outer can, and the liquid injection hole 1 and its peripheral portion are processed into a concave shape inside the bottomed rectangular outer can. Reference numeral 4 denotes a sealing lid plate that is conductively fixed to the opening of the bottomed rectangular outer can 1, and the joint between the two is welded by laser welding. Reference numeral 5 is an insulating member of a gas seal. Reference numeral 6 denotes a positive electrode terminal pin, which is fixed through the insulating member 5 having a glass seal. 3 is a stainless steel ball sealing plug, which is filled with an electrolytic solution through a liquid injection hole, and then the sealing plug 3 is pressed into the liquid injection hole 2, and the head portion is resistance-welded to be integrated with an outer can to hermetically seal. To be done.

The battery assembled as described above is referred to as Battery A of the present invention.

Next, a cross-sectional view of an upper surface and a side surface of a conventional battery B assembled in the same manner as the battery of the present invention except that the liquid injection hole of the bottomed rectangular outer can and its peripheral portion are not concave. Is shown in FIG.

Table 1 shows the results of measuring the amount X of protrusion of the sealing plug welded portion from the outer side surface of the bottomed rectangular outer can of Battery B. FIG. 3 shows measurement points of the amount of protrusion X of the battery B at this time. Also for the battery A of the present invention, the amount Y of protrusion from the outer side surface of the bottomed rectangular outer can was measured in the same manner as the battery B. The measurement points are shown in FIG. In the case of Battery A, since the sealing plug welded portion is not protruded from the outer side surface of the bottomed rectangular outer can and is recessed inward, the amount of protrusion Y is indicated by a negative sign.

[0017]

[Table 1] It can be seen from Table 1 that the battery A of the present invention has no protrusion of the sealing plug weld portion as compared with the conventional battery B.

[0018]

[Effect of device]

 From the above, according to the present invention, when the liquid injection hole and the peripheral portion of the bottomed rectangular outer can are made to be concave, and the liquid injection hole is sealed by the sealing plug, the welded portion of the sealing plug is However, it does not protrude from the outer side surface of the bottomed rectangular outer can, and the battery storage space can be made small, and its practical value is extremely large.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an upper surface and a side surface of a prismatic sealed battery according to the present invention.

FIG. 2 is a cross-sectional view of an upper surface and a side surface of a conventional rectangular sealed battery.

FIG. 3 is a view showing measurement points of a protrusion amount of a sealing plug weld portion of a conventional rectangular sealed battery.

FIG. 4 is a view showing measurement points of a protrusion amount of a sealing plug welded portion of a rectangular sealed battery of an example.

[Explanation of symbols]

 1 Square bottomed outer can 2 Filling hole 3 Stainless steel ball sealing plug 4 Sealing lid plate 5 Gas seal insulating member 6 Positive electrode terminal pin 11 Bottomed rectangular outer can 12 Injection hole 13 Stainless steel ball sealing plug 14 Sealing lid plate 15 Insulating member of glass seal 16 Positive electrode terminal pin X Protrusion amount of sealing plug welding part Y Protrusion amount of sealing plug welding part

Claims (1)

[Scope of utility model registration request] 1. An electrolytic solution injection hole (2) is formed on a side surface of a bottomed rectangular outer can (1) that also serves as a unipolar terminal, and the injection hole (2) is a metal sealing port. A closed prismatic battery, which is hermetically sealed by a stopper (3), and has a bottomed rectangular outer can (1) in which a peripheral portion of a liquid injection hole is formed in a concave shape.