KR20070075945A - Protection circuit module of no-welding, contacting-connection type and battery pack employed with the same - Google Patents

Abstract

A protection circuit module of a non-welding and contact-connection type, and a battery pack including the same are provided to reduce the assembling process of a battery pack, the working time and consequently the production cost owing to omission of a welding or soldering process. The protection circuit module(100) of a non-welding and contact-connection type includes a printed circuit board(PCB) on which a protection circuit for controlling the overcharge, overdischarge and overcurrent of a secondary battery is printed, a pair of shafts(120) which are attached in a state of being electrically connected to the protection circuit, onto a bottom side of the PCB, a washer(130) combined to the shaft(120) and a compressive spring(140) which is installed between the PCB and the washer(130) to elastically support the washer(130).

Description

Protection circuit module of non-welding contact connection type and battery pack including same {Protection Circuit Module of No-welding, Contacting-connection Type and Battery Pack Employed with the Same}

1 is an exploded perspective view of a protection circuit module according to an embodiment of the present invention;

2 is a schematic diagram of a process of mounting the protection circuit module of FIG. 1 in a battery cell;

3 is a perspective view of a battery pack according to an embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protection circuit module of a non-welding contact connection method and a battery pack including the same. More specifically, a printed circuit board (PCB) on which a protection circuit for controlling overcharge, overdischarge, and overcurrent of a secondary battery is printed. A pair of shafts attached to the lower end of the PCB in an electrically connected state to the protection circuit, a washer coupled to the shaft, and a compression spring mounted between the PCB and the washer in a state in which the washer is elastically supported. It provides a protective circuit module consisting of.

With the development of technology and increasing demand for mobile devices, the demand for secondary batteries is also rapidly increasing. Among them, lithium secondary batteries with high energy density, high operating voltage, and excellent storage and life characteristics are used for various mobile devices as well as various electronic products. It is widely used as an energy source.

However, the lithium secondary battery contains various combustible materials, and there is a danger of overheating or explosion due to overcharging, overcurrent, other physical external impact, etc., and thus has a serious safety drawback. Therefore, in the lithium secondary battery, a protection circuit module (PCM) capable of effectively controlling abnormal conditions such as overcharging is embedded in a state connected to the battery cell.

PCM is composed of field effect transistor (FET) as a switching element to control current, and passive elements such as voltage detector, resistor and capacitor, and overcharge, overdischarge, overcurrent, short circuit, reverse voltage of battery By preventing the explosion, overheating or leakage of the battery and deterioration of the charge / discharge characteristics, and by suppressing the degradation of the electrical performance and physicochemical abnormal behavior, the risk factor is eliminated and the service life is extended. This PCM is mainly in the form of a printed circuit board, and the stabilizers are mounted on its outer surface.

In general, the PCM is connected to the battery cell by a welding or soldering method through a conductive nickel plate. That is, the nickel plate is connected to the terminal of the PCM by welding or soldering, and then the nickel plate is welded or soldered to the electrode terminal of the battery cell to connect the PCM to the battery cell to manufacture a battery pack.

In this case, a large number of welding or soldering is required in order to configure the battery pack, and such welding, etc., must be performed in a very precise work due to the small structure of the secondary battery, and thus the likelihood of defects is high. In addition, the addition of such a process during the manufacturing process of the product acts as a factor that increases the product cost.

Therefore, there is an urgent need for a method of assembling a PCM and a battery cell without undergoing a spot welding or soldering process.

Accordingly, an object of the present invention is to solve the problems of the prior art as described above and the technical problems that have been requested from the past.

Specifically, the object of the present invention is to shorten the assembly process and work time of the battery pack by eliminating the welding or soldering process that requires a lot of time and skilled technology when the electrical connection between the battery cell and PCM, ultimately lower the manufacturing cost It is to provide a protection circuit module of a contactless contact connection method.

Still another object of the present invention is to provide a battery pack having a stable coupling structure comprising such a protection circuit module.

The protection circuit module of the contactless contact connection method according to the present invention for achieving the above object is a substrate (PCB) printed with a protection circuit for controlling overcharge, overdischarge and overcurrent of the secondary battery, connected to the protection circuit A pair of shafts attached to the lower end of the PCB in a closed state, a washer coupled to the shaft, and a compression spring mounted between the PCB and the washer in a state in which the washer is elastically supported. It consists of.

Therefore, the protective circuit module according to the present invention is connected to the electrode terminal of the battery cell by a contact method by a shaft formed on the lower end of the PCB constituting the protective circuit module and a washer elastically coupled thereto, so as to connect a nickel plate or the like. Electrical connections can be made without welding or soldering the members.

In the present invention, the PCB has a structure in which a protection circuit for controlling overcharging, overdischarging, and overcurrent of a secondary battery (battery cell) is printed on a resin composite in a board form. The back is mounted on a part of its outer surface. Representative examples of the resin composites include epoxy resin composites. External input and output terminals are formed on the upper surface of the PCB, and the shaft is attached to its opposite surface, that is, the lower surface.

The shaft is connected to the protection circuit of the PCB, and a pair is provided to be connected to the positive and negative terminals of the battery cell, respectively. The position at which the two shafts are attached depends on the position of the electrode terminals in the battery cell. For example, in a typical square battery, the negative electrode terminal is formed at the center of the protruding shape and the positive electrode terminal is entirely formed on the top surface of the battery cell insulated from it, so in this battery cell structure, one of the shafts is in the center and the other is in the center. It is attached to the bottom surface of the PCB at a distance from it by a predetermined distance.

In one preferred example, the shaft consists of a relatively large diameter end facing the PCB so that attachment to the PCB can be achieved more stably.

The form of attachment of the shaft to the PCB can vary and can be attached, for example, by welding, soldering, or integrally forming.

In addition, the coupling end of the shaft in contact with the washer may preferably be of a projection structure to be coupled in an interference fit manner.

The washer is coupled to one end of the shaft in contact with the electrode terminal of the battery cell to make an electrical connection, the electricity from the battery cell to the PCB is mainly achieved via the washer and the shaft.

The form of engagement of the washer to the shaft may vary, in which the through-hole is formed in the center of the washer so that it can be coupled to the end of the shaft (“engagement end”) in an interference fit manner.

In one preferred example, the washer is a main body having a through-hole formed in the center so that the engaging end of the shaft can be coupled in an interlocking manner, and the main body so that the engaging end of the shaft does not protrude while being coupled to the shaft. It may be a structure consisting of a connection diameter of a larger diameter.

The compression spring mounted between the PCB and the washer serves to resiliently support the washer coupled to the shaft. Preferably, the compression spring may also be made of a metal material to assist in energizing through the washer and shaft.

The present invention also provides a battery pack comprising the protective circuit module.

In general, a battery pack has a structure in which a protection circuit module is mounted on a battery cell capable of charging and discharging, and the outside thereof is wrapped in a pack case.

The battery cell has a structure in which the electrode assembly of the anode / separator / cathode structure is embedded in the cell case in the state in which the electrolyte is impregnated, the battery pack of the present invention in a pouch-shaped case of a rectangular metal can or aluminum laminate sheet A battery cell in which the electrode assembly is built in may be preferably used. In particular, a rectangular battery cell in which an electrode assembly is built in a rectangular metal can can be preferably used.

The pack case may have various structures, and in one preferred example, the battery pack may be manufactured by assembling the protective circuit module and the battery cell in a box or frame pack case.

Hereinafter, a protective circuit module and a battery pack according to an embodiment of the present invention will be described with reference to the drawings, but this is for easier understanding of the present invention, and the scope of the present invention is not limited thereto.

1 is an exploded perspective view of a protection circuit module according to an embodiment of the present invention.

Referring to FIG. 1, the protection circuit module 100 includes a protection circuit board (PCB) 110, a pair of shafts 120, a washer 130, and a compression spring 140. The PCB 110 is printed with a protection circuit for controlling overcharge, overdischarge, overcurrent, etc. of a battery cell (not shown) on an electrically insulating substrate having a predetermined thickness. An external input / output terminal (not shown) is formed on the top surface of the PCB 110.

A pair of shafts 120 are attached to the bottom surface of the PCB 110 at a distance away from the center thereof. The shaft 120 has a relatively large diameter at the end 122 facing the PCB 110, so that attachment to the PCB 110 can be more stably achieved. In addition, the opposite end or coupling end 124 of the shaft 120 has a rather coarse protrusion structure, providing a stable engagement with the washer 130 assembled in an interference fit manner.

Washer 130 is formed in the form of a loudspeaker, the main body 134 is formed with a through hole 132 in the center so that the end 124 of the shaft 120 can be coupled in a force-fit method, It is composed of a connection extension 136 of a larger diameter than the body 134 so that its end 124 does not protrude when coupled to the shaft 120.

Accordingly, when the through hole 132 of the washer 130 is inserted into the end portion 124 of the shaft 120 in the state where the compression spring 140 is opened, the washer 130 is formed by the compression spring 140. It is elastically coupled to the shaft 120 by the support force. When the protective circuit module 100 assembled as described above is mounted on a battery cell (not shown), the washer 130 makes electrical connection to the electrode terminal of the battery cell in a contact manner, and the PCB 110 from such an electrode terminal. The energization of the furnace is mainly achieved by the washer 130 and the shaft 120 and assisted by the energization by the compression spring 140.

2 schematically illustrates a process of mounting a protection circuit module in a battery cell according to an embodiment of the present invention.

The battery cell 200 has a structure in which an electrode assembly in which an electrolyte is impregnated is sealed in the metal can 210 of a rectangular shape, and electrode terminals (not shown) are formed on an upper end thereof. In addition, the safety vent 220 is formed on the outer surface of the metal can 210 to effectively discharge the battery cell 200 when it is expanded by the gas generated therein.

The protection circuit module 100 is mounted on the top of the battery cell 200, and may make an electrical connection with the battery cell 200 in the same manner as described above. In addition, since the connection portion between the protection circuit module 100 and the battery cell 200 is elastically supported by the compression spring 140, it is possible to maintain a stable connection state even when an external shock or the like is applied.

3 is a view schematically showing the shape of a battery pack according to an embodiment of the present invention.

Referring to FIG. 3, the battery pack 300 has a structure in which a rectangular frame 310 surrounds the outer circumferential surface of the battery cell 200. That is, in the same process as in FIG. 2, a battery pack 300 may be manufactured by mounting a protection circuit module (not shown) on the top of the battery cell 200 and mounting it on the frame 310. Accordingly, the protection circuit module can be electrically connected to the battery cell 200 without welding or soldering a connection member such as a nickel plate.

Although described above with reference to the drawings according to an embodiment of the present invention, those skilled in the art will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

As described above, the protection circuit module according to the present invention reduces the assembly process and the working time of the battery pack ultimately the manufacturing cost by eliminating the welding or soldering process that requires a lot of time and skilled technology when electrical connection with the battery cell It is possible to lower, to implement the automation of the assembly process, as well as to improve the structural stability of the battery pack.

Claims (8)

A protective circuit module of a contactless contact connection method, comprising: a printed circuit board (PCB) on which a protection circuit for controlling overcharging, overdischarging, and overcurrent of a secondary battery is printed; And a pair of shafts, a washer coupled to the shaft, and a compression spring mounted between the PCB and the washer while resiliently supporting the washer. The protection circuit module according to claim 1, wherein the shaft has a relatively large diameter at an end facing the PCB. The protective circuit module according to claim 1, wherein the shaft has a protruding structure so that the coupling end with the washer can be coupled in an interference fit manner. 4. The protection circuit module according to claim 3, wherein a through hole is formed in a center of the washer to which the coupling end of the shaft can be coupled in an interference fit manner. According to claim 1, The washer is the main body is formed with a through-hole in the center so that the engaging end of the shaft can be coupled in a clamping manner, and the engaging end of the shaft in the state coupled to the shaft so as not to protrude Protective circuit module, characterized in that consisting of a connection extension of a larger diameter than the main body. A battery pack comprising a protective circuit module according to any one of claims 1 to 4. The battery pack according to claim 6, wherein the battery cell is a rectangular battery cell in which an electrode assembly is built in a rectangular metal can. The battery pack as claimed in claim 6, wherein the battery pack is manufactured by assembling the protective circuit module and the battery cell in a box type or frame type pack case.

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