JP4721335B2 - Terminal board and secondary battery protection circuit unit having the same - Google Patents

Description

  The present invention relates to a terminal board attached to various electronic circuit units by soldering, and a protection circuit unit for a secondary battery including the terminal board.

  In general, a secondary battery used as a power source of a mobile phone, a portable personal computer, or the like is equipped with a protection circuit unit for preventing overcharge and overdischarge.

As shown in FIG. 5A, in the conventional protection circuit unit 104, an electronic component 146 (not shown in detail) such as an IC chip is mounted on a wiring pattern (not shown) arranged on the electronic circuit board 145. A terminal plate 147 is soldered on the land 141. In the protection circuit unit 104, the terminal plate 147 is electrically connected to the terminal 133 of the secondary battery unit 103 by welding or the like, as shown in FIG. 4B.
Finally, as shown in FIG. 4A, the protection circuit unit 104 is housed together with the secondary battery unit 103 in a box-shaped battery case 102 whose one side is open, and then sealed by a case cover 105, and then the secondary battery unit 103 is sealed. The battery 101 is integrated.
JP 2004-303618 A

Incidentally, as shown in FIG. 4A, the protection circuit unit 104 is provided with a connection terminal 142 on the surface on the battery case 102 side for connection to an electronic device such as a mobile phone. It is necessary to be accommodated in the battery case 102 so as to be exposed from the window 122 provided in the battery.
That is, when the terminal board 147 soldered to the protection circuit unit 104 and the terminal 133 connected to the secondary battery unit 103 are welded, the alignment of the protection circuit unit 104 with respect to the secondary battery unit 103 is controlled. It was necessary to carry out accurately using tools etc., resulting in deterioration of workability and cost increase.

Furthermore, the soldering of the terminal board 147 and the land 141 soldered to the protection circuit unit 104 is a bonding between the flat surfaces, and the bonding area is limited. Therefore, the bonding strength is weak, and the terminal board 147 is peeled off. It sometimes occurred.
Further, as a countermeasure, as shown in FIG. 5B, a protection circuit unit 204 is proposed in which an opening 200 is provided at the joint portion of the terminal plate 247 to increase the joint area (see Patent Document 1), but reflow, etc. Since the solder for joining may scatter or wrap around the upper surface of the terminal board 247 from the opening 200 during heating by the above, a defect in appearance occurs, and a correction work has been invited.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a secondary battery unit (electronic device unit) while being soldered to a protection circuit unit (electronic circuit unit) of a secondary battery. The terminal plate is electrically connected to the terminals of the electronic circuit unit, and the bonding strength with the electronic circuit unit substrate is enhanced, and when the electronic circuit unit is connected to the terminal of the electronic device unit, the alignment is performed. It is an object of the present invention to provide a terminal board that can be facilitated, and a secondary battery protection circuit unit including the terminal board.

  In order to solve the above problems, a terminal plate of the present invention is a terminal plate that is soldered to an electronic circuit unit and electrically connected to a terminal of an electronic device unit, and the soldering is performed. And at least one concave portion is formed on the surface of the electronic device unit, and a protruding portion on which the electronic circuit unit can be positioned in contact with the terminal is formed on the surface connected to the terminal of the electronic device unit. It is characterized by.

  In the above configuration, it is preferable that one surface of the terminal plate is a surface on which the solder joint is made, and the other surface is a surface connected to the terminal of the electronic device unit.

  Moreover, in order to solve the said subject, the secondary battery protection circuit unit of this invention was provided with said terminal board.

According to the present invention configured as described above, since the concave portion formed in the joint portion with the land becomes a solder pool, the solder joint area is increased and the joint strength is increased as compared with the case where there is no concave portion. Can be made.
In addition, since the concave portion is completely closed with respect to the protruding portion side of the terminal plate, the solder does not scatter or sneak into the protruding portion side of the terminal plate during heating by reflow or the like. The above defects and correction work can be avoided.

In addition, according to the present invention, when the electronic circuit unit is electrically connected to the electronic device unit, the protruding portion of the terminal plate and the tip of the terminal of the electronic device unit are brought into contact with each other, thereby easily aligning them. It can be carried out.
Therefore, it is not necessary to perform alignment using a separate jig or the like, so that the workability in the assembling work can be improved and the cost can be reduced.

Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.
1A and 1B are diagrams showing a protection circuit unit provided with a terminal board according to the present invention, FIG. 1A is a perspective view thereof, FIG. 1B is a perspective view showing a bottom side thereof, and FIG. 1C is a XX line in FIG. It is a principal part expanded sectional view in alignment with. 2A is an exploded perspective view showing each configuration of the secondary battery to which the protection circuit unit shown in FIG. 1 is applied, and FIG. 2B is an enlarged plan view showing the main part of the secondary battery. Here, the secondary battery is obtained by integrating the secondary battery unit and the protection circuit unit with a case.
In FIG. 1 and FIG. 2, various electronic components mounted and solder at each joint are omitted for convenience.

  As shown in FIG. 2A, the secondary battery 1 according to this embodiment includes a secondary battery unit 3 and a protection circuit unit 4 that are electrically connected in a box-shaped battery case 2 that is open on one side. The open surface is closed by a flat plate-like case cover 5.

As shown in FIG. 2A, the secondary battery unit 3 is a flat battery body 31 having a flat rectangular parallelepiped shape made of a lithium ion battery, and a plate shape extending from electrodes (not shown) provided on both side surfaces 32 thereof. Terminal 33.
2A and 2B, the terminal 33 is bent in an L shape along the corner of the secondary battery body 31 and extends to the front surface 34 of the secondary battery body 31. 4 is electrically connected.

  As shown in FIG. 1, the protection circuit unit 4 has a wiring pattern (not shown) and a soldering land 41 formed on one surface of an electronic circuit board 45, and the secondary battery unit 3 is protected on the wiring pattern. It is composed of various electronic components 46 (not shown in detail) mounted to form a circuit and a terminal plate 47 soldered to the land 41, and on the other surface (see FIG. 1B) A connection terminal 42 for connecting to an electronic device is formed.

The terminal plate 47 is made of a known material, for example, nickel, and is formed in a plate shape as shown in FIG. 1, and at least a part of the terminal plate 47 is pressed and deformed so that the concave portion 48 and the protruding portion 49 are integrated. Is formed. As shown in FIG. 1C, the terminal board 47 is disposed so that the recess 48 is on the land 41, and is attached to the electronic circuit board 45 by soldering.
At this time, as shown in FIG. 2B, the position of the protrusion 49 comes into contact with the tip of the terminal 33 in the secondary battery unit 3 so that the protection circuit unit 4 can be positioned with respect to the secondary battery unit 3. ing.

  The protection circuit unit 4 configured as described above is disposed on the front surface 34 of the secondary battery unit 3 as shown in FIG. 2B, and the protrusion 49 is brought into contact with the tip of the terminal 33 of the secondary battery unit 3. Thus, positioning with respect to the secondary battery unit 3 is performed. Thereafter, the protection circuit unit 4 is electrically connected to the secondary battery unit 3 by welding and joining the terminal plate 47 and the terminals 33 of the secondary battery unit 3.

  As shown in FIG. 2A, the battery case 2 has a rectangular window 22 on the front surface 21, and when the secondary battery unit 3 and the protection circuit unit 4 are stored in the battery case 2, the protection circuit unit 4. The connection terminal 42 is exposed from the window 22 so that the connection terminal 42 can be connected to an electronic device (not shown) such as a mobile phone.

  The secondary battery 1 configured as described above is connected to an electronic device such as a mobile phone, and is used while being protected from overcharge and overdischarge by the protection circuit unit 4.

As shown in FIG. 1C, the terminal plate 47 joined to the protection circuit unit 4 has a concave portion 48 formed in the joint portion with the land 41 as a solder pool. The solder bonding area is increased, and the bonding strength to the land 41 is enhanced.
In addition, since the recessed part 48 is completely closed with respect to the protrusion part 49 side of the terminal board 47, at the time of the heating by reflow etc., a solder scatters or wraps around to the protrusion part 49 side of the terminal board 47. Therefore, there is no appearance defect and correction work can be avoided.

  2B, when the protection circuit unit 4 is electrically connected to the secondary battery unit 3, the projection 49 in the terminal plate 47 is brought into contact with the tip of the terminal 33 in the secondary battery unit 3. It is easily positioned by touching. Therefore, it is not necessary to perform positioning using a separate jig, so that workability in assembling work can be improved and cost can be reduced.

As mentioned above, although embodiment of this invention was described, demonstrating a specific example, this invention is not limited to these specific examples.
As shown in FIG. 3A, another protrusion 49 ′ may be provided on the surface of the terminal board 47 on the land 41 side so that the terminal board 47 can be easily aligned with the electronic circuit board 45 at the time of joining. .
A plurality of recesses 48 formed in the terminal board 47 may be provided. In this case, it is possible to further increase the bonding area and the bonding strength.
Moreover, although the recessed part 48 and the protrusion part 49 are integrally formed by the press in this embodiment, you may form separately, respectively. In this case, as shown in FIG. 3B, the recess 48 and the protrusion 49 may be formed on the same surface of the terminal plate 47.
Moreover, the terminal board concerning this invention is applicable not only as a protection circuit unit of a secondary battery but as a terminal board of various electronic circuit units.

FIG. 1A is a perspective view of the protection circuit unit according to the present embodiment, FIG. 1B is a perspective view of the bottom surface side thereof, and FIG. 1C is an enlarged cross-sectional view of a main part along line XX in FIG. It is. It is a figure which shows the structure of the secondary battery concerning this embodiment, FIG. 2A is the disassembled perspective view, FIG. 2B is the principal part enlarged plan view. It is a top view which shows the modification of the terminal board concerning this embodiment. It is the disassembled perspective view which shows the structure of the conventional secondary battery, and the Z arrow enlarged view which shows the principal part. It is a perspective view which shows the conventional protection circuit unit.

Explanation of symbols

1 Secondary battery 2 Battery case 3 Secondary battery unit (electronic equipment unit)
4 Protection circuit unit (electronic circuit unit)
5 Case Cover 21 Case Cover Front 22 Window 31 Secondary Battery Main Body 32 Secondary Battery Main Body Side 33 Terminal 34 Secondary Battery Main Body Front 41 Land 42 Connection Terminal 45 Electronic Circuit Board 46 Electronic Component 47 Terminal Plate 48 Recess 49 49 ′ Projection 101 Secondary battery 102 Battery case 103 Secondary battery unit 104 Protection circuit unit 105 Case cover 122 Window 133 Terminal 141 Land 142 Connection terminal 145 Electronic circuit board 146 Electronic component 147 Terminal board 200 Opening 204 Protection circuit unit 241 Land 245 Electronic circuit board 246 Electronic component 247 Terminal board

Claims (3)

A terminal plate that is soldered to the electronic circuit unit and electrically connected to the terminals of the electronic device unit,
At least one recess is formed on the surface where the solder joint is made, and the protrusion on which the electronic circuit unit can be positioned by contacting the terminal on the surface connected to the terminal of the electronic device unit The terminal board characterized by the above.   2. The terminal board according to claim 1, wherein one surface of the terminal board is a surface to be soldered and the other surface is a surface connected to a terminal of the electronic device unit.   A protection circuit unit for a secondary battery, comprising the terminal plate according to claim 1.

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