JPH0475251A - Battery pack - Google Patents

Abstract

PURPOSE:To integrate battery members as a whole by holding a terminal holder by means of a pair of cases in such a manner that the cases each having a recess in its inner face surround the holder from the circumference thereof, and covering a flat cell with the cases with the inner surface of each case in sticking contact with the cell. CONSTITUTION:A terminal holder 10 which has terminal plates 8, 9 electrically connected to each other by spot welding opposite to current collecting plates 4, 5 is disposed on the side face of a flat cell 7. A pair of cases 11, 12 are each recessed at its inner face and the outer peripheral portions of the cases 11, 12 have respective portions to be fitted with each other. The fitting portions are joined together by means of ultrasonic welding. A battery pack formed therefore has almost no space in the internal structure of the cell 7 nor between the cell 7 and each case 11, 12, providing an integrated structure as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a battery pack, and more particularly to the structure of a battery pack used as a power source for portable equipment and the like.

BACKGROUND OF THE INVENTION Conventionally, in a conventional battery pack of this type, a plurality of cylindrical batteries 23 having positive and negative electrodes 21 and 22 at both ends are arranged.
Connect the lead plates 24 to each pole by spot welding, further connect the lead wires 25, 26 to the positive and negative terminals of the battery at both ends, and connect the lead wires 25, 26 to the terminal boards 28, 29 provided on the case 27, respectively. It had a structure as shown in Figure 5, in which electricity was extracted from the system. Therefore, the unit cell 23 had a structure that was fitted between the upper and lower cases 27.

Problems to be Solved by the Invention In such a conventional structure, it takes many man-hours to connect the unit cells 23, the lead wires 25 and 26 for connection take up space, and the fixation of the unit batteries 23 is unstable. This caused problems in soldering between the lead wires 25 and 26 and the terminal plates 28 and 29.

As a result, the external dimensions of the case 27 become large, resulting in a battery with poor volumetric efficiency. Furthermore, as a power source for portable devices, two to three spare battery packs are required, and these are often carried around. Therefore, the battery bank must have a structure that is resistant to drop impact.

In this respect as well, the conventional battery pack consists of a unit cell 23 and a case 2.
7 was large, and the thinner the case was, the weaker it became.

If the unit cell was a small sealed lead-acid battery, the battery itself would be heavy, so it was necessary to eliminate the gap between the contents and the case and increase the overall strength by integrating them.

The present invention solves these problems, and aims to provide a battery pack with good volumetric efficiency and excellent impact resistance.

Means for Solving the Problem In order to solve this problem, the battery of the present invention is provided by holding a terminal holder so as to surround it from the periphery with a pair of split cases having recesses on the inner surface, and In a battery pack, the case and the flat cell are integrated by fixing the surfaces of the case and the flat cell with an adhesive, and by ultrasonic welding the joints of the case, on the surface of the case, A label is pasted across the joint of the case.

Effect With this configuration, the battery pack of the present invention holds the terminal holder so as to surround it from the periphery with a pair of cases having recesses on the inner surface, and the inner surface of the case closely covers the flat unit cell, thereby making it possible to securely hold the terminal holder. There is almost no gap between the cell and its case, and the terminal holder is firmly held by the pair of cases, resulting in an integrated structure.

In order to prevent the current collector plate and the inner surface of the case from coming into close contact with each other due to the bulge of the terminal plate spot-welded to the surface of the current collector plate of the flat unit cell, a bulge of the terminal plate on the inner surface of the case is provided. By providing a shallow recess, the battery pack can be more closely bonded, and both inner surfaces of the case and the surface of the current collector plate are fixed with adhesive, and the mating portion of the case is ultrasonically welded. By affixing a label to the surface of the case across the joint portion of the case, the joint strength of the case is further strengthened.

EXAMPLE A battery pack according to an example of the present invention will be described below with reference to the drawings. In Figures 1.2.3 and 4, 1 is a positive electrode plate, 2 is a negative electrode plate, 3 is a separator, these are combined to form an electrode plate group, and 4 and 5 are a synthetic resin film material on one side. A current collector plate made of a laminated metal plate, sandwiched from both sides with a synthetic resin film facing the surface in contact with the electrode plate group, and the current collector plates 4 and 5 are electrically connected to the positive electrode plate 1 or the negative electrode plate 2, respectively. do. Reference numeral 6 denotes a synthetic resin body surrounding the electrode plate group, which is thermally welded to the current collecting plates 4 and 5, which are laminated with a synthetic resin film material and a metal plate on one side, to form a flat cell 7.
shall be. A terminal holder 10 having terminal plates 8 and 9 which are electrically connected to each other by spot welding is disposed on the side surface of the flat cell 7, facing the current collector plates 4 and 5. Reference numeral 11.12 denotes a pair of upper and lower cases that surround and hold the terminal holder 10 from the periphery and at the same time cover the entire surface of the flat cell 7 in close contact with the cell.The inner surfaces of the pair of cases 11.12 are recessed. , the outer peripheries of the cases 11 and 12 have portions that fit into each other. These mating parts are joined by ultrasonic welding.

17 is the joint portion thereof. Therefore, the completed battery pack has an entirely integrated structure with almost no gaps between the flat cell 7 and its cases 11 and 12, as well as the internal structure of the flat cell 7.

The current collector plate 4.5 and the inner surface of the case 1 are connected by the bulges of the terminal plates 8 and 9 spot-welded to the surface of the current collector plate 4.5 of the unit cell 7.
In order to prevent the terminals 1' and 12' from coming into close contact with each other, shallow recesses 13 and 14 are provided on the inner surfaces of the case 11' and 12' to correspond to the terminal plate bulges, so that the battery pack can be firmly attached. Become.

Also, both inner surfaces 11'12' of the case 11.12
A label 16 is attached to the surface of the pair of cases 11.12 across the joint 17 where the current collecting plates 4 and 5 are fixed with adhesive 15.16 and the fitting portion of the pair of cases 11.12 is ultrasonically welded. Paste it to make the joint 17 stronger.

Effects of the Invention As is clear from the above description of the embodiments, the battery pack of the present invention, unlike the conventional structure, greatly simplifies the number of man-hours required to electrically connect the flat unit cells. There is no need for lead wires, which eliminates wasted space and allows for a compact design. The fixation of the flat battery is stable, and the connection between the lead wire and terminal plate is completed by simple spot welding instead of soldering. This eliminates many troubles that often occur in soldering.

As a result, the external dimensions of the case are reduced, making it possible to provide a battery with good volumetric efficiency. In addition, the battery pack used as a power source for portable devices has a structure that is resistant to impact from being dropped. In this respect as well, it is possible to reduce the gap between the flat cell and the case, which could not be achieved with conventional battery punctures, making it possible to create a strong battery pack even if the case is thin.

Even if the battery is heavy, such as a small sealed lead-acid battery, the overall strength can be increased by eliminating the gap between the battery and the case, and by integrating the case, battery, and other parts.

By pasting a label on the case surface across the joint between a pair of cases, the joint strength of the cases can be further strengthened.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing the structure of a battery pack according to an embodiment of the present invention, and Fig. 2 is an external appearance 7 of the battery pack.
Flat cell, 10...Terminal holder 11.1
2... Case, 15... Adhesive, 16
·····label.

Claims (1)

[Claims] A group of electrode plates consisting of a positive electrode plate, a negative electrode plate and a separator,
A current collector plate consisting of a metal plate laminated with a synthetic resin film material on one side is sandwiched with the synthetic resin film facing the electrode plate group, and the current collector plate is connected to the positive electrode plate or the negative electrode plate, respectively. At the same time, a terminal holder having a terminal plate connected to the current collector plate is disposed on the side surface of the flat unit cell, which is thermally welded to the synthetic resin body surrounding the electrode plate group, and a pair of The terminal holder is held so as to be surrounded from the periphery by a split case having a recess on the inner surface, and the inner surface of the case and the surface of the flat cell are fixed with adhesive, and the joints of the case are treated with ultrasonic waves. A battery pack in which the case and the flat cell battery are integrated by welding, and a label is affixed to the surface of the case across the joint portion of the case.