JP2001210307A - Connecting method of ptc element, jig for connecting ptc element and ptc element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable that the soldering of lead wire with a metal-electrode plate of PTC element directly without raising the initial resistor value of the PTC element, and aim at a cost reduction, and eliminate the failure due to resistance welding. SOLUTION: In a connecting method of PTC element 2 to have a metal- electrode plate 2b, the soldering of lead wire 5 with a connecting part of this metal-electrode plate 2b is made in the state that heat radiation plates 20, 22 are surface contacted between PTC element main body 2a side and the connecting part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of connecting a PTC element which incorporates a plurality of lithium ion secondary batteries and is suitable for use in manufacturing a battery pack.
The present invention relates to a jig for connecting a TC element and a PTC element.

[0002]

2. Description of the Related Art Conventionally, a battery pack using a plurality of, for example, six, lithium ion secondary batteries has been proposed. The configuration of this battery pack is, for example, as shown in FIG. 5, in which three sets of six lithium ion secondary batteries 1a to 1f connected in parallel are connected in series, and the positive electrode is connected to the PTC element 2 and the temperature. The negative electrode of three sets of serial circuits of two lithium ion secondary batteries 1a to 1f connected in parallel to each other through a series circuit of fuses 3 and connected to the positive terminal 4a of this battery pack is connected to the negative electrode of this battery pack. This is connected to the terminal 4b.

The PTC element 2 is a metal electrode plate 2b made of, for example, a nickel plate on a conductive polymer material (element body) 2a having a characteristic that the resistance value increases as the temperature rises as shown in FIG. Are used as overcurrent and overheat protection elements.

That is, in the PTC element 2, when an overcurrent flows or is overheated, the electric resistance increases, and the current between the positive and negative terminals 4a and 4b of the battery pack is minutely limited to protect a circuit and the like. can do.

When the power is turned off and the temperature of the PTC element 2 drops, the resistance value of the PTC element 2 drops, so that the PTC element 2 can be used again without replacement.

However, when the PTC element 2 is heated to, for example, 130 ° C. or more and has a high resistance value, there is a phenomenon that the initial resistance value increases even when the temperature returns to room temperature. For example, the initial resistance value is 30 mΩ. When the PTC element 2 temporarily overheats to, for example, 130 ° C. or more and becomes a high resistance value, the initial resistance value becomes 40 mΩ even when the temperature returns to the normal temperature.

Therefore, when the lead wire 5 is soldered to the metal electrode plate 2b of the PTC element 2 in order to connect the PTC element 2 in a circuit as shown in FIG. As described above, there is a disadvantage that the initial resistance value of the PTC element 2 is increased. Therefore, conventionally, as shown in FIG. 7, one end of the lead wire 5 is first inserted into the hole 6a of the tab 6, and then the other end of the lead wire 5 is connected. After soldering to the tab 6, the tab 6 is attached to the metal electrode plate 2 of the PTC element 2.
The connection portion b was connected by resistance welding.

[0008]

Therefore, conventionally, this P
To connect the TC element 2 in the circuit, first, the lead wire 5 is soldered to the tab 6, and then the tab 6 is connected to the PTC element 2.
Resistance welding to the metal electrode plate 2b of
Compared to a device that is directly soldered to the metal electrode plate 2b of the TC element 2, the number of connection steps and the number of parts used are increased, so that the cost of the product (battery pack) increases. Also, there was a problem that a defect occurred, which caused a decrease in reliability and yield.

In view of the above, the present invention enables a lead wire to be directly soldered to a metal electrode plate of a PTC element without increasing the initial resistance value of the PTC element, thereby reducing costs and using resistance welding. The purpose is to eliminate defects.

[0010]

According to the present invention, there is provided a method of connecting a PTC element, the method comprising the steps of: connecting a heat radiating plate between the PTC element body side of the metal electrode plate and the connecting portion; In this state, the lead wire is soldered to the connection portion of the metal electrode plate.

According to the present invention, the lead wire is soldered to the connection portion in a state where the heat radiating plate is in surface contact between the PTC element body side of the metal electrode plate and the connection portion. The heat is radiated through the plate, and even if the lead wire is directly soldered to the connection portion of the metal electrode plate, the heat of the PTC element main body does not increase up to, for example, 130 ° C., and the initial resistance value of the PTC element increases. Never.

The jig for connecting a PTC element according to the present invention comprises an upper block and a lower block, at least one of which is made of a metal having good heat conductivity, and a connection portion of the upper block with a lead wire of a metal electrode plate of the PTC element. A hole for soldering is formed in a portion corresponding to the above, and the blocks made of metal of the upper block and the lower block are brought into surface contact between the PTC element body side of the metal electrode plate and the connection portion.

According to the present invention, the block made of the metal of the upper block and the lower block is replaced with the PT of the metal electrode plate.
Since the C-element body and the connecting portion are in surface contact with each other, the heat generated when the lead wire is soldered to the connecting portion of the metal electrode plate is radiated through the block made of the metal, and Even if a lead wire is directly soldered to the connection part, the heat of the PTC element main body does not increase up to, for example, 130 ° C., and the initial resistance value of the PTC element does not increase.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
Method for connecting C element, jig for connecting PTC element, and PTC
An example of an embodiment of the device will be described.

First, an example of an embodiment of a method for connecting a PTC element according to the present invention will be described with reference to FIGS. In the present example, as shown in FIG. 1A, as shown in FIG. 6, a hole 10 for inserting the lead wire 5 is formed in the connecting portion of the lead wire 5 of the metal electrode plate 2b of the PTC element 2.
In this case, solder plating can be applied to the connection portion of the lead wire 5 of the metal electrode plate 2b.

When connecting the PTC element 2 in, for example, a battery pack manufacturing process, first, as shown in FIG. 1B, one end of the lead wire 5 is inserted into the hole 10 of the metal electrode plate 2b of the PTC element 2, and then PTC as shown in FIG.
One end of the lead wire 5 is connected to the connection portion of the metal electrode plate 2b using a jig for connecting the elements. FIG. 1A,
In B, 3 is a thermal fuse.

In FIG. 4, reference numeral 20 denotes a rectangular parallelepiped upper block made of a metal having good heat conductivity, for example, aluminum, copper, metal silicon, germanium, and alloys mainly including these metals. Metal electrode plate 2
b of the metal electrode plate 2b.
The upper block 2 is added to a portion corresponding to the portion where 0 is formed.
A soldering hole 21 having a predetermined size penetrating through 0 is formed.
A PTC element body 2a is provided on the lower surface of the upper block 20.
And recesses 20a and 20b for accommodating the thermal fuse 3 are formed.

In FIG. 4, reference numeral 22 denotes a rectangular parallelepiped lower block made of a metal having good heat conductivity, for example, aluminum, copper, silicon metal, germanium, or an alloy mainly containing these metals. A PTC element body 2a and a metal electrode plate 2b of the PTC element 2;
A recess for accommodating the thermal fuse 3 is formed.

The upper block 20 is fixed to the lower block 22 via a hinge so as to be openable and closable. Also, an elastic heat conductive material such as synthetic rubber or silicon is disposed on a portion of the concave portion on the upper surface of the lower block 22 corresponding to a portion between the PTC element body 2a side of the PTC element 2 and the connection portion of the PTC element 2;
The PTC element 2 is arranged at a predetermined position on the upper surface of the lower block 22, and when the upper block 20 is closed, the lower surface of the upper block 20 contacts the metal electrode plate 2 of the PTC element 2.
b so as to make good surface contact between the PTC element body 2a side and the connection portion.

Reference numerals 23a and 23b denote magnets provided on the lower surface of the upper block 20 and the upper surface of the lower block 22, respectively. The magnets 23a and 23b attract each other when the upper block 20 is closed. Things.

Next, a case where the lead wire 5 is directly soldered to the connection part of the metal electrode plate 2b of the PTC element 2 using the jig for connecting the PTC element as shown in FIG. 4 will be described.

First, as shown in FIG.
With the PTC element 2 open,
a and the metal electrode plate 2b are placed at predetermined positions of the recesses on the upper surface of the lower block 22, and the tips of the one lead wire 5 and the other lead wire 5 with the thermal fuse 3 are respectively connected to the one and the other metal electrode plate 2b. And 2b are respectively inserted into holes 10 and 10 formed in the connection portions, and are mounted at predetermined positions of the concave portions on the upper surface of the lower block 22.

In this case, one and the other metal electrode plates 2b
2b, that is, the holes 10 and 10 are formed, and the portions where the lead wires 5 and 5 are inserted correspond to the soldering holes 21 and 21 of the upper block 20.

Next, the upper block 20 is closed and chucked by the magnets 23a and 23b. At this time, the PTC element body 2 of the metal electrode plate 2b of the PTC element 2
a and the connecting portion are in surface contact with the lower surface of the upper block 20.

Next, the soldering holes 2 of the upper block 20
Through 1 and 21, the connection portion of the metal electrode plate 2b and the lead wire 5 are directly soldered. In this case, heat at the time of soldering is radiated through the upper block 20 and the lower block 22 of a metal having good heat conductivity, such as aluminum, copper, metal silicon, germanium, and alloys mainly including these metals. Almost no heat is transferred to the PTC element main body 2a, and the PTC element main body 2a is not heated to, for example, 130 ° C., and the initial resistance value does not increase.

Therefore, according to this embodiment, the lead wire 5 can be directly soldered to the metal electrode plate 2b of the PTC element 2, so that the tab 6 is not required and the need for resistance welding is eliminated as compared with the prior art. The number of parts is reduced and the number of connection steps is reduced, so that cost can be reduced and defects due to resistance welding can be eliminated.

In this case, it is not necessary to provide the hole 10 at the connection portion of the metal electrode plate 2b of the PTC element 2, but it is faster to provide the hole 10 and insert the lead wire 5 into the hole 10. Solderable.

In the example of FIG. 1, the metal electrode plate 2 of the PTC element 2
2A and 2B, cutouts 11 are formed on both sides of the connection portion of the metal electrode plate 2b, and the cutouts 11 are formed as shown in FIGS.
As shown in FIG. 2B, after the lead wire 5 is wound, soldering may be performed in the same manner as described above, or as shown in FIGS. Extension piece 1 extending in a direction perpendicular to electrode plate 2b
2 may be provided, and the extension piece 12 may be bent as shown in FIG.

In the above example, both the upper block 20 and the lower block 22 are formed of a metal having good heat conductivity. However, one of the upper block 20 and the lower block 22 is formed of a metal having good heat conductivity. The other may be formed by bakelite or the like. In this case, the surface of the block formed of a metal having good heat conductivity is the P of the metal electrode plate 2b of the PTC element 2.
Surface contact is made between the TC element body 2a side and the connection part.

In the above example, a metal block having good heat conductivity is used. However, a heat radiating plate having good heat conductivity is used, and this heat radiating plate is used as the P electrode of the metal electrode plate 2b of the PTC element 2.
It can be easily understood that the same operation and effect as described above can be obtained even if the TC element main body 2a is brought into surface contact between the connection portion and the lead wire 5 is directly soldered to this connection portion.

Further, the present invention is not limited to the above-described example, but may adopt various other configurations without departing from the gist of the present invention.

[0032]

According to the present invention, the lead wire is soldered to the connection part in a state where the heat radiating plate (metal block) is in surface contact between the connection part and the PTC element body side of the metal electrode plate of the PTC element. The heat generated by the soldering is dissipated through the heat radiating plate (metal block), and even if the lead wire is directly soldered to the connection portion of the metal electrode plate, the heat of the PTC element main body is, for example, 130 ° C. Does not increase, and the initial resistance value of the PTC element does not increase.

Therefore, according to the present invention, the lead wire can be directly soldered to the metal electrode plate of the PTC element, so that no tab is required and there is no need for resistance welding as compared with the prior art, so that the number of parts used is small. In addition, the number of connection steps is reduced, cost can be reduced, and defects due to resistance welding can be eliminated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an example of a main part of a process of a method for connecting a PTC element of the present invention.

FIG. 2 is a configuration diagram showing another example of the main part of the steps of the method for connecting a PTC element of the present invention.

FIG. 3 is a configuration diagram showing another example of the main part of the steps of the method for connecting a PTC element of the present invention.

FIG. 4 is a configuration diagram showing an example of an embodiment of a connection jig for a PTC element of the present invention.

FIG. 5 is a connection diagram illustrating an example of a battery block.

FIG. 6 is a plan view showing an example of a PTC element.

FIG. 7 is a configuration diagram showing a connection example of a conventional PTC element.

[Explanation of symbols]

2 ‥‥ PTC element, 2a ‥‥ PTC element body, 2b ‥‥
Metal electrode plate, 5mm lead wire, 10mm hole, 11mm notch, 12mm extension piece, 20mm upper block, 21mm
{Soldering hole, 22} Lower block, 23a, 23b}
‥magnet

Continuation of the front page (72) Inventor Fumiya Sato 1-1 Shimosugishita, Takakura, Hiwada-cho, Koriyama-shi, Fukushima F-term in Sony Energy Tech Co., Ltd. (reference) 5H022 AA09 AA19 BB13 CC12 KK01

Claims (8)

[Claims] 1. A method of connecting a PTC element having a metal electrode plate, wherein a lead wire is connected to the connection part of the metal electrode plate in a state in which a heat sink is in surface contact between the PTC element body side of the metal electrode plate and the connection part. A method of connecting a PTC element, wherein the PTC element is soldered. 2. The method of connecting a PTC element according to claim 1, wherein a hole is provided in a connection portion of the metal electrode plate, and soldering is performed after inserting the lead wire into the hole. Method of connecting PTC elements. 3. The method for connecting a PTC element according to claim 1, wherein a notch is provided in a connection portion of the metal electrode plate, and soldering is performed after the lead wire is wound around the notch. Characteristic connection method of PTC element. 4. The method for connecting a PTC element according to claim 1, wherein an extension piece extending in a direction perpendicular to the metal electrode plate is provided at a connection portion of the metal electrode plate, and the extension piece is bent to form the lead wire. A method of connecting a PTC element, wherein soldering is performed after the PTC element is sandwiched. 5. A soldering hole is provided at a portion corresponding to a connection portion of a metal electrode plate of a PTC element of the upper block with at least one of which is made of a metal having good heat conductivity. And a block made of metal of the upper block and the lower block is brought into surface contact between the metal electrode plate and the PTC element body side and the connecting portion. Utensils. 6. A PTC element having a metal electrode plate, wherein a hole for inserting the lead wire is provided in a connection portion of the metal electrode plate where the lead wire is connected. 7. A PTC element having a metal electrode plate, wherein a notch for winding the lead wire is provided at a connection part of the lead wire of the metal electrode plate. 8. A PTC element having a metal electrode plate, wherein an extension piece extending in a direction orthogonal to the metal electrode plate that sandwiches the lead wire is provided at a connection portion of the lead wire of the metal electrode plate. PTC element.