JP2000077048A - Pack battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance productivity and reliability of a protecting circuit by fitting housing components of a lead, a metal terminal plate, a protecting element, a protecting circuit board, and a unit cell to a recessed part of a lower case, then joining the lower case and an upper case. SOLUTION: Terminal plates 10a-10c corresponding to terminal windows 9a-9c are fit to projection formed in the inner bottom of a terminal groove 33 of a lower case 30, and a protecting circuit board 7 is also fitted to the terminal groove 33. A lead 5 for connecting a positive terminal of a unit cell 1a and the protecting circuit board 7 is fitted to a lead groove 34a, and a lead 4 is fitted to a lead groove 32. Similarly, a lead 6 for connecting a negative terminal of a unit cell 1b and the protecting circuit board 7 is fitted to a lead groove 34b. Finally, unit cells 1a, 1b are fitted to battery grooves 31a, 31b respectively. A joining surface 35 of the lower case 30 side is applied with a solvent for case resin, an upper case 20 is fitted to the lower case 30, as a lid, and both cases are joined by applying pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery pack in which one or more unit cells and components such as a protection element, a protection circuit board, and connection terminals are incorporated in a resin case. The present invention relates to a battery pack in which at least one of a resin case divided into two cases is provided with a concave portion into which a unit cell and a component are fitted.

[0002]

2. Description of the Related Art As a structure of a battery pack, a structure shown in FIG. 4 is generally known. In FIG. 4, reference numeral 1 denotes a unit cell, and two cells are connected in series. 20 is the upper case, 30
Is a lower case, and these are combined to form a casing of the battery pack. The battery pack is created according to the following procedure.

[0003] An insulating tape 2 having heat resistance is attached to the body of one unit cell 1a. An adhesive 3 is applied to the surface of the insulating tape 2 and fixed to the body of the other unit cell 1b.

In order to electrically connect the unit cells 1a and 1b, a negative electrode terminal surface of the unit cell 1a and a unit cell 1b
Lead 4 is spot-welded to the positive electrode terminal surface of Also, one end of the conducting wire 5f is connected to the positive electrode terminal surface of the unit cell
One end of the conducting wire 6f is spot-welded to the negative electrode terminal surface.

The other ends of the lead 4, the conducting wire 5 f, and the conducting wire 6 f are soldered to predetermined positions on the side of the unit cell of the protection circuit board 7, and the metal terminal plate 10 is moved to each predetermined position on the surface of the protection circuit board 7. Solder.

[0006] Double-sided tapes 11a and 11b are attached to the inner bottom surface of the lower case 30 divided into two parts.

Insulating paper 8 is interposed between the unit cell 1 and the protection circuit board 7, and while holding these three members, the metal terminal plates 10 a, 10 b, 10 c are connected to the corresponding positive electrode output terminals of the resin case 9. Window 9a, charging terminal window 9b, fit into the projections provided inside negative electrode output terminal window 9c, press the unit cell group against the adhesive surface of double-sided tape 11a, 11b,
The protection circuit board 7, the insulating paper 8, and the unit cell group are housed and fixed in 9.

[0008] Double-sided tapes 11a and 11b are attached to portions of the unit cell 1 that are in contact with the inner surface of the upper case 20.

A solvent is applied to the upper surface edge of the lower case 30 and the upper case 20 is pressure-bonded to obtain a finished product.

[0010]

In recent years, the demands for the cost of products have become strict, and the productivity of the battery pack, which is a component of the product, has been improved in the manufacturing process of the battery pack. In addition, the structure must be simplified. In addition, with the increase in energy density of unit cells,
Since appropriate charge / discharge control for unit cells is required, high reliability of a protection circuit incorporated in a battery pack is required.

However, since the connection between the components is performed by spot welding or soldering, it takes a long time for careful work, which is against the improvement of productivity. As a countermeasure, it was necessary to reduce the work time and the number of parts required for the entire process. Also, it is not preferable to solder a lead, a conductive wire, or a protective element to a protective circuit board on which elements that are vulnerable to high heat are densely mounted, in order to ensure high reliability of the protective circuit.

The present invention has been made in order to solve such a problem.
It is an object of the present invention to provide a battery pack that is excellent in productivity and reliability of a protection circuit.

[0013]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention provides a lead case, a metal terminal plate, a metal terminal plate, and a recess formed in at least one of a resin case housing divided into an upper case and a lower case. A predetermined circuit is formed by fitting the protection element, the protection circuit board, and the unit cell. As a result, higher productivity and higher reliability of the protection circuit can be obtained than before.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a battery pack for accommodating a unit cell in a resin case housing formed by combining an upper case and a lower case, wherein the lower case has a concave portion. After fitting a lead, a metal terminal plate, a protection element, a protection circuit board, and a storage part of a unit cell to the recess, and joining the lower case and the upper case to each other, A predetermined circuit is formed in the double-sided tape, adhesive,
It has the effect of eliminating the need for spot welding work, soldering work, and insulating paper and insulating tape required for insulating parts.

According to a second aspect of the present invention, all of the electrical connection points between the components are pressed against each other, and are housed in a space where the components cannot be separated after the resin case serving as the lid is joined. Even if it is not welded or soldered, or if it is dropped or vibrated, it has the function of maintaining continuous conductivity only by being pressed.

According to the third and fourth aspects of the present invention, the surface of the electrical connection between the parts to be in pressure contact with one or both surfaces is roughened, made uneven, or adhered, or pressed into contact. The parts have elasticity. In other words, it has the effect of strengthening the friction and the degree of compression of the pressed surface against the displacement of the component on the pressed surface which may be caused by dropping or vibration, thereby more reliably maintaining continuous conductivity.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of the battery pack in this embodiment. The external dimensions, the built-in unit cells and the components are the same as those of the conventional battery pack shown in FIG.
Detailed description is omitted.

Hereinafter, the structure of the battery pack will be described along the assembly procedure. First, each component is fitted into a groove provided in the lower case 30. A groove is formed in the lower case 30 made of the bisected polycarbonate resin, and a positive electrode output terminal window 9a, a charging terminal window 9b, and a negative electrode output are formed on protrusions provided on the inner bottom of the terminal groove 33 dug down to near the bottom of the lower case. After fitting the corresponding gold-plated nickel terminal plates 10a, 10b, and 10c in the same order into the terminal windows 9c, the protection circuit board 7 is also fitted into the terminal grooves 33.

Next, after the nickel lead 5 for connecting the positive terminal of the unit cell 1a and the protection circuit board 7 is fitted into the lead groove 34a, the unit cell 1a, the unit cell 1b and the protection circuit are inserted into the lead groove 32. The nickel lead 4 for three-way connection with the substrate 7 is fitted. Similarly, the negative electrode terminal of the unit cell 1b and the protection circuit board 7 are also provided in the lead groove 32b.
Is fitted with a nickel lead 6 for connection.

Finally, the unit cells are placed in the lower case into which the leads, terminals, and protection circuit board have been fitted. The unit cells 1a and 1b are respectively fitted in semicircular battery grooves 31a and 31b formed in the center of the lower case corresponding to the external shape of the battery. A solvent for dissolving the polycarbonate resin is applied to the joint surface 35 on the lower case 30 side, and the upper case 20, which is the other polycarbonate resin case, is used as a lid and pressure-bonded to complete the product.

The dimensions and shape of each groove of the lower case 30 are designed so that the parts are always pressed against each other after the upper case 20 is joined. It is also possible to implement a method of fitting components into a passage provided on the inner surface of the resin case, for example, one in which holding guides are scattered so as to be easily fitted.

FIG. 2 is an exploded perspective view of a battery pack showing another embodiment of the battery pack according to the present invention. This figure 2
5 shows a state immediately before the upper case 20 and the lower case 30 are joined by pressure, and the unit cell 1, the protection circuit board 7, and the leads are fitted into the respective grooves of the lower case 30.
The inner surface shape of the upper case 20 has a groove. These hold down the protection circuit board 7 and the unit cell 1 after pressure bonding the bonding surface 35 of the lower case and the bonding surface 23 of the upper case. That is, it is also fitted into the battery groove 21 and the circuit board groove 22 of the upper case, and has an action of preventing the parts at the electrical connection points from being detached from each other even if they are dropped or vibrated.

If the built-in components are held, the inner surfaces of both cases are flat in order to completely fit the protection circuit board and the unit cell to the top, or the heat generated by the unit cell is reduced. Various means can be implemented, such as one in which an air passage for escaping to the outside is provided at a location on the inner surface of any resin case that is not adversely affected by falling or vibration.

FIG. 3 is a diagram showing the surface shape of the electrical connection portion, and FIG. 3A shows the tip shape of the lead terminal. In this figure, a nickel lead terminal surface 1 is shown.
3, 14, 15, and 16 are roughened, knurled,
The surface is made elastic by bending and bending. Also,
FIG. 3 (b) is a diagram showing a connection state between the protection circuit board and the terminals. The solder surface 17a of the protection circuit board 7 and the nickel lead terminal surface 17b in contact therewith are each formed with a fold and minute. The contact area of the portion is enlarged and the surface is made uneven. These have the effect of increasing the friction and compression of the contact surface and preventing the components at the electrical connection points from shifting even when subjected to a drop or vibration.

In the above, examples of surface processing that are easy to understand in appearance have been described. However, other methods such as quenching or annealing a metal material to increase elasticity, or using a part having a contact surface coated with a conductive adhesive, etc. In addition, processing effective for dropping and vibration can be performed.

Next, a specific example of the present invention will be described. The product of the present embodiment and the conventional product whose appearance is shown in FIG. 5 were produced by 1000 pieces, and the average working time per one piece was produced, the number of parts and materials for producing one piece, and obtained from the inspection of the finished product. The number of protection circuit board abnormalities and the number of component connection failures were compared. These results are shown in (Table 1).

[0028]

[Table 1]

As is clear from Table 1, the product of the present embodiment can provide superior effects on the productivity and the reliability of the protection circuit as compared with the conventional product.

[0030]

As described above, according to the present invention, the work time can be reduced, the number of parts can be reduced, and the work of soldering to the protection circuit board is not required. The advantageous effect that the reliability of the substrate can be significantly improved can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the structure of a battery pack according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the structure of a battery pack according to another embodiment of the present invention.

FIG. 3A is a perspective view showing a tip shape of a lead terminal. FIG. 3B is a perspective view showing a connection state between the protection circuit board and the lead terminal.

FIG. 4 is a perspective view showing the structure of a conventional battery pack.

FIG. 5 is an external view of a battery pack.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Unit cell 2 Insulating tape 3 Adhesive (not shown) 4, 5, 6 Lead 7 Protection circuit board 8 Insulation paper 9 Terminal surface 10 Terminal board 20 Upper case 30 Lower case

Claims (4)

[Claims] 1. A battery pack for accommodating a unit cell in a resin case housing combining an upper case and a lower case, wherein the lower case has a concave portion, and a lead, a metal terminal plate, A battery pack wherein the lower case and the upper case are joined to each other after the protection element, the protection circuit board and the storage parts of the unit cell are fitted. 2. The storage component according to claim 1, wherein the storage component is pressed against each other at an electrical connection portion of the storage component fitted into the concave portion, and after the upper case is joined, the storage component cannot be removed from the concave portion. Battery pack. 3. The battery pack according to claim 2, wherein at least one side of the storage component at the electrical connection point is roughened. 4. The battery pack according to claim 2, wherein at least one of the storage components at the electrical connection portion is provided with elasticity.