JP3286524B2 - Battery pack - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection between cases of a battery pack.

[0002]

2. Description of the Related Art A battery pack has a Ni-C
In order to store a battery such as a d-battery, the case is divided into two parts. The two divided cases are closed by joining their outer peripheral edges to form a battery pack.

For joining between cases, for example, joining by ultrasonic welding or an adhesive is known. FIG. 3 shows a joining method between cases by ultrasonic welding. In this method, one case A and the other case B are adjusted to predetermined positions. At this time, for example, a rib or the like is provided on the outer peripheral edge of the case A so that the rib contacts the outer peripheral edge of the case B. Then, the case A and the case B are set on the ultrasonic receiving jig 10, and the ultrasonic horn 11 is applied from the case B side to apply a sufficient ultrasonic vibration. At this time, the joint surfaces between the cases are welded by ultrasonic vibration, and the cases are firmly joined.

[0004] Joining by ultrasonic welding can save the trouble of applying an adhesive and can achieve more robust joining than joining by an adhesive. However, the joining by ultrasonic welding may have a bad influence on parts and the like housed in the case due to the vibration of the ultrasonic horn.

In recent years, lithium-ion batteries have been commercialized, and a battery pack containing a lithium-ion battery houses a printed circuit board on which a protection circuit is mounted together with the battery in order to prevent overcharge and overdischarge. are doing. For this reason, in a battery pack containing a printed circuit board, if the cases are joined by ultrasonic welding, circuit components may be lost due to ultrasonic vibrations, which may make it difficult to perform joining by ultrasonic welding. was there.

On the other hand, bonding with an adhesive does not adversely affect parts and the like housed in a case, but requires a considerable amount of time until the adhesive is cured.
There is a problem that production efficiency is reduced. Further, it is necessary to prevent the displacement of the joining surface of the case until the adhesive is cured. For example, FIGS. 4 and 5
As shown in (1), after joining the case A and the case B with an adhesive, the case A and the case B had to be temporarily fixed with, for example, a rubber band 20 or a tape 21.

[0007]

Accordingly, the present invention eliminates the need for temporary fixing with a rubber band or tape as in the case of joining the cases with an adhesive, thus reducing the time and labor required for manufacturing. Provided is a battery pack that can be shortened.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a battery,
In a battery pack including a battery case for accommodating a battery, the battery case is formed into at least two parts, and each divided case constitutes a battery case by joining outer peripheral edges to each other. A joining rib for joining to the other split case with an adhesive and a temporary fixing rib for joining are formed.

[0009] The temporary fixing rib is characterized in that it is a rib for temporarily fixing to the other case by ultrasonic welding. In this case, since the ultrasonic vibration applied to the temporary fixing rib is temporarily fixed, a weak vibration that does not adversely affect the internal components of the battery pack is applied.

[0010] A groove for inserting the joining rib and the temporary fixing rib provided in the one divided case is formed on the outer peripheral edge of the other divided case.

[0011]

According to the present invention, the temporary fixing rib formed on the outer peripheral edge of one of the divided cases performs the temporary fixing when the divided cases are joined. Therefore, the temporary fixing with the rubber band or the tape which has been required until the adhesive is cured can be eliminated.

Further, by applying ultrasonic vibration to the temporary fixing rib and performing temporary fixing by ultrasonic welding, the temporary fixing can be performed very easily. Note that the ultrasonic vibration applied to the temporary fixing rib may be very weak vibration.
There is no problem that adversely affects internal parts.

Further, by forming a groove for inserting the joining rib and the temporary fixing rib provided on the one divided case on the outer peripheral edge of the other divided case, the positioning of the rib can be facilitated. Also, it is possible to prevent the adhesive from flowing out.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 are exploded perspective views of a battery case constituting a battery pack of the present invention. The battery case 1 is divided into two parts, one case A and the other case B. Although not shown, one lithium-ion battery and a protection circuit for protecting the lithium-ion battery from being overcharged or overdischarged are housed between the two cases A and B. Two or more lithium ion batteries may be stored in accordance with the voltage of the equipment to be used.
The protection circuit is mounted on a printed circuit board, and is electrically connected to the battery by a lead plate. A battery pack is formed by these built-in batteries and protection circuits, and the battery case.

The battery pack is used as a power source for portable equipment such as a mobile phone and a personal computer, and is mounted on a charger when charging. Therefore, this battery pack is provided with engaging claws 2 for attachment to a portable device or a charger at four places on the side surface of the case B. Reference numeral 3 denotes an external terminal for electrical connection during charging and discharging.

As described above, the battery pack does not need to take out the built-in battery, and is stored in the case.
It can be attached to equipment and connected electrically. Furthermore, since the built-in lithium ion battery is a rechargeable battery that can be used repeatedly, there is no need to replace the battery. Therefore, the case A and the case B, which are divided into two parts, are firmly joined so that once they are joined, they cannot be easily disassembled.

Next, the outer peripheral edges 4 and 5 of the case A and the case B are formed in a substantially rectangular frame shape, and the battery case is assembled by joining them together. A joining rib 6 and a temporary fixing rib 7 are formed on the outer peripheral edge 4 of the case A. A total of four temporary fixing ribs 7 are formed on each of the two left and right sides, and the joining ribs 6 are formed substantially all around except for the temporary fixing ribs 7. A portion where no rib exists is provided between the joining rib 6 and the temporary fixing rib 7. On the other hand, a groove 8 into which the joining rib 6 is inserted and a groove 9 into which the temporary fixing rib 7 is inserted are formed on the outer peripheral edge 5 of the case B.

When joining the case A and the case B to each other, first, a printed circuit board on which a lithium ion battery or a protection circuit is mounted is housed in the case B. And case A
The joining rib 6 or the groove 8 for inserting the rib 6
Apply adhesive to Then, the two cases A and B are joined by inserting the joining ribs 6 into the groove portions 8. At this time, due to the presence of the groove 8, even if the adhesive is sufficiently applied, the adhesive does not protrude from the outer peripheral edge of the case and does not flow out from the inside of the groove 8 until the adhesive is hardened. Strong bonding can be performed.
At this time, the temporary fixing rib 7 is in a state of being inserted into the groove 9.

Next, until the adhesive is cured, the two cases are temporarily fixed so as not to be displaced from each other. The temporary fixing is performed by ultrasonic welding of the portion of the temporary fixing rib 7. When performing ultrasonic welding, a battery case is set on an ultrasonic receiving jig 10 as shown in FIG. 3, and an ultrasonic horn 11 is applied from the case B side to apply ultrasonic vibration. The position where the ultrasonic horn 11 is applied is the position of the engaging claw 2, which is exactly the position facing the temporary fixing rib 7. The ultrasonic vibration at this time is a very weak vibration due to temporary fixing, so that components are not dropped from the built-in printed circuit board.

When the temporary fixing is performed by the temporary fixing ribs 7, it is not necessary to fix the battery case with a rubber band or a tape until the adhesive is hardened as in the conventional case. The performance is improved.

The recesses 12 formed in the case B,
13 is for positioning with the device and the charger,
At the time of mounting, it is designed to fit into a projection provided on the device or the charger side. Although not shown, the aperture 14 is provided with a slide switch.
The switch is switched to two positions so that a charge state and a discharge state can be displayed, so that the user can know the state of the battery. Furthermore, two round holes 15
Is a hole for inspecting the continuity of the protection circuit or the like after the lithium ion battery and the printed circuit board on which the protection circuit is mounted in the battery case. After the inspection, a label sticker is attached, so that the appearance is not noticeable.

[0022]

According to the present invention, the temporary fixing rib formed on the outer peripheral edge of one of the divided cases performs the temporary fixing when the divided cases are joined. Therefore, the temporary fixing with the rubber band or the tape which has been required until the adhesive is cured can be eliminated.

Further, by applying ultrasonic vibration to the temporary fixing ribs and performing temporary fixing by ultrasonic welding, the temporary fixing can be performed very easily. Since the ultrasonic vibration applied to the temporary fixing ribs is temporarily fixed, it may be a very weak vibration. Therefore, even when a circuit component or the like is incorporated in the battery pack, the internal components are adversely affected. there is no problem.

Further, by forming a groove for inserting the joining rib and the temporary fixing rib provided in the one divided case on the outer peripheral edge of the other divided case, the positioning of the rib can be facilitated. Also, it is possible to prevent the adhesive from flowing out.

As a result, for example, even for a battery pack of a lithium ion battery having a built-in circuit component or the like, the joining between the cases can be performed easily and reliably without causing the missing of the built-in circuit component or the like. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state where a battery case of the present invention is divided.

FIG. 2 is a perspective view of the battery case of FIG. 1 viewed from below.

FIG. 3 is a diagram showing a joining method between cases by ultrasonic welding.

FIG. 4 is a perspective view of a state where the battery case is temporarily fixed with a rubber band and a tape.

FIG. 5 is a perspective view of the battery case of FIG. 4 as viewed from below.

[Explanation of symbols]

 A One divided case B The other divided case 2 Engagement claw 4, 5 Outer edge 6 Joining rib 7 Temporary fixing rib 8, 9 Groove

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazushi Komaru 2-5-1-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (56) References JP-A-1-135649 (JP, U) (58 ) Surveyed field (Int.Cl. ⁷ , DB name) H01M 2/10

Claims (1)

(57) [Claims] 1. A battery pack comprising a battery and a battery case for housing the battery, wherein the battery case is formed into at least two parts, and each divided case forms a battery case by joining outer peripheral edges to each other. , At least one of the split cases is temporarily fixed between the other case by an adhesive and a joining rib for bonding to the other split case by an adhesive.
A temporary fixing ribs for the formed and the other minute
The outer peripheral edge of the split case is
Grooves are formed for inserting joint ribs and temporary fixing ribs
Battery pack, characterized in that it is.