KR20070080868A - Pcm of assembling type structure and battery pack employed with the same - Google Patents

Abstract

A protective circuit module with a coupling structure for manufacturing a battery pack is provided to control over-recharge/discharge and over-current of battery, to be combined with battery cell and to assemble the battery pack easily by adopting a pair of connection elements with a groove form structure to be fitted with flat electrode terminals of the battery cell. A module PCM(400) comprises a pair of connection elements at the bottom end of PCM as electrically connected to a protective circuit and, each of the connection elements is formed in a groove type connection structure to which a flat electrode terminal of a battery cell(200) is fitted and coupled. PCM consists of PCB(printed circuit board) structure. The PCB is combined with the connection elements at the bottom end thereof, in order to connect the bottom end to an end side at which electrode terminals(230,232) of the battery cell are formed. The connection elements are in a cubic form and located at the both bottom ends of PCM. The groove of the connection structure is oriented in parallel to width of PCM.

Description

PCM of Assembling Type Structure and Battery Pack Employed with the Same}

1 is a perspective view of a battery pack including a fastening structure PCM according to an embodiment of the present invention;

2 is a perspective view of a fastened PCM according to one embodiment of the present invention;

3 and 4a are perspective views of one exemplary connecting member in a fastening PCM according to the invention, and FIG. 4b is a vertical cross sectional view taken along line A-A of FIG. 4a;

FIG. 5 is a vertical sectional view of a structure in which a compression spring is mounted on the connecting member structure of FIG. 4B according to another embodiment of the present invention; FIG.

6A to 6C are schematic diagrams illustrating a series of assembling processes for connecting a PCM to a battery cell in a battery pack.

The present invention relates to a protection circuit module (PCM) having a fastening structure and a battery pack including the same. More particularly, the present invention relates to a module including a protection circuit for controlling overcharge, overdischarge, and overcurrent of a battery. A pair of connection members are mounted at the bottom of the PCM in an electrically connected state with the protection circuit, and the connection member is a protection circuit module having a structure in which a plate-shaped electrode terminal of a battery cell can be inserted and fastened, and such protection circuit. Provided is a battery pack including a module.

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 PCM capable of effectively controlling an abnormal state such as overcharging is incorporated in a state connected to a 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 It prevents the explosion, overheating or leakage of the battery and deterioration of the charge and discharge characteristics, and suppresses the deterioration of the electrical performance and physical and chemical behavior, thereby removing the risk factors and extending the service life.

In general, PCM is connected to the battery cell by a strong welding or soldering method using a conductive material such as nickel plate. However, the welding or soldering method has a disadvantage of requiring a high-technical work and a large working space. In addition, when a physical shock is applied to the battery cell, it may cause an electrical short, etc., may cause a safety problem such as fire and explosion.

Therefore, a number of techniques for attaching and mounting a PCM to a battery cell without using a welding or soldering method have been proposed, but are easy to manufacture, have a simple connection structure, the bonding force between the battery cell and the PCM, and the electrode terminal and the PCM of the battery cell. The technology for the PCM structure that can effectively enhance the electrical connection between the liver has not been developed yet.

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.

The inventors have conducted extensive research and various experiments, and by connecting the PCM to the battery cell simply by inserting the electrode terminal of the battery cell into the connecting member having the groove-shaped connection structure, a lot of time and skill It has led to the development of a PCM structure that can omit the welding or soldering process that requires technology and can increase the bonding force between the battery cell and the PCM and the electrical connection force between the electrode terminal of the battery cell and the PCM.

Accordingly, it is an object of the present invention to provide a fastening type PCM comprising a connection member having a groove-shaped connection structure and which is easy to manufacture.

Still another object of the present invention is to provide a battery pack having excellent mechanical fastening and electrical connection to a battery cell by including the fastening PCM.

PCM (protective circuit module) of the fastening structure according to the present invention for achieving this object is a module including a protection circuit for controlling the overcharge, over-discharge and over-current of the battery, electrically connected to the protection circuit of the PCM In a state, a pair of connecting members are attached to the lower end of the PCM, and the connecting member has a groove-type connection structure in which the plate-shaped electrode terminals of the battery cell can be inserted and fastened.

Accordingly, the PCM according to the present invention can achieve electrical connection and mechanical fastening with the electrode terminal by a simple operation of inserting the plate-shaped electrode terminal into the fastening groove formed in the connecting member thereof.

In one preferred embodiment, the PCM of the present invention has a printed circuit board (PCB) structure, the connection member is a PCB so that the lower end of the PCB can be coupled to the end surface on which the electrode terminal of the battery cell is formed It may be a structure that is mounted on the bottom surface of the.

The connection member is not particularly limited as long as it is electrically connected to the protection circuit and has a fastening groove into which the electrode terminal is inserted. In a specific example, the connecting members are generally hexahedral and are respectively installed at both ends of the bottom surface of the PCM, and the fastening grooves are oriented side by side in the width direction of the PCM.

The fastening groove of the connection member is preferably in a state where the elastic plate member extending from the bottom surface of the connection member is bent inwardly so that the inserted plate-shaped electrode terminal can be brought into close contact with the inner surface thereof. A part of it (bending extension part) is in close contact with the inner side of the upper end surface opposite to the lower end surface, so that the elastic close contact portion between the bending extension part and the upper end surface acts as a fastening groove. Therefore, the plate-shaped electrode terminal is inserted into the elastic close contact between the bent extension and the top surface, thereby achieving a stable coupling.

Preferably, in order to facilitate insertion of the electrode terminal into the fastening groove, the end portion of the bent extension portion may be a structure that is bent upward to the rear beyond the elastic close contact with the top surface to form a pressing head. Therefore, by pressing the pressure head protruding upward from the rear end with respect to the direction in which the electrode terminal is inserted, the contact area between the bent extension and the upper surface is spaced apart and the plate-shaped electrode terminal is inserted therein, and then releases downward force on the pressure head. The electrode terminal is tightly coupled between the bending extension part and the upper end surface by the elastic force of the lower surface bent portion.

In some cases, in order to increase the coupling force of the connecting member to the electrode terminal, an opening having a predetermined size is further formed at the rear of the upper end surface, and an elastic protrusion protruding upwardly from the bending extension portion at the corresponding position is formed. Thus, when the plate-shaped electrode terminal is inserted between the bent extension and the top surface, at least a portion thereof engages the protrusion to induce a more stable coupling.

Another example of increasing the coupling force of the connection member to the electrode terminal is a structure in which an elastic member such as a compression spring is provided between the bottom surface and the bent extension portion.

The connection member is preferably made of a metal material, for example, by bending the metal plate, the lower surface, the upper surface, the bent portion, the bent extension can be produced in an integral form. Since this structure is novel in itself, the present invention also provides a connecting member having a structure as shown in FIG.

In some cases, only the bent portion requiring elasticity may be made of a metal sheet.

The manner of mounting the connecting member to the PCM body can vary and is preferably mounted in a welded manner to provide a high bonding force.

The present invention also relates to a battery pack comprising the PCM electrically connected to a battery cell.

The battery cell is preferably a pouch type battery cell in which a battery assembly of a positive electrode / separation membrane / cathode is incorporated in a pouch type case of a laminate sheet including a resin layer and a metal layer.

The connection method of the PCM to the battery cell may also vary. For example, after bending the upper sealing part protruding upward from the electrode terminal of the battery cell to be in close contact with the body of the battery cell, the electrode terminal is vertical. It can be achieved by bending downward and inserting into the fastening groove of the PCM. In some cases, after bending the upper sealing portion of the battery cell vertically in the state in which the electrode terminal of the battery cell is inserted into the fastening groove of the PCM, the PCM may be bent vertically downward.

In this way, a battery pack is manufactured by mounting a battery cell connected with a PCM to a pack case. Preferably, an electrically insulating resin is filled into the battery cell and the portion of the PCM by insert injection molding, thereby manufacturing a more stable battery pack. have.

Hereinafter, more specific details 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 a perspective view of a battery pack including a PCM of a fastening structure according to an embodiment of the present invention. For ease of understanding, the drawings show a combined state of the battery cell and the PCM in a state where the pack case is omitted.

Referring to FIG. 1, the battery pack 100 has a battery cell 200 in which a plate-shaped electrode terminal 230 protrudes from one side thereof, and a connection member 400 that may be coupled to the electrode terminal 230 thereof. It includes a PCM (300) attached to.

The battery cell 200 is manufactured by heat-sealing the case in a state in which an electrode assembly is embedded in a pouch type case of an aluminum laminate sheet. Due to such thermal fusion, sealing portions 210, 212, and 220 are respectively formed on both bottom and top surfaces thereof. The pair of plate-shaped electrode terminals 230 and 232 connected to the electrode assembly protrude from the upper sealing portion 220.

The sealing parts 210, 212, and 220 are bent vertically upward to closely contact the battery cell body, and the plate-shaped electrode terminals 230 and 232 are bent vertically downward again to form a connection member of the PCM 300. 400). More detailed structures of the PCM 300 and the connecting member 400 are shown in FIGS. 2 to 4.

First, FIG. 2 is a perspective view of a fastening PCM according to one embodiment of the present invention.

Referring to FIG. 2, the PCM 300 has a structure of a printed circuit board (PCB) in which a protection circuit for controlling overcharge, overdischarge, overcurrent, etc. of a battery is printed on a plate structure of an epoxy composite. One side 310 of the PCM 300 is attached with a connecting member 400 which is electrically connected to such a protection circuit and is formed with a fastening groove 410 into which a plate-shaped electrode terminal (not shown) can be inserted. On the other surface 320, an external input / output terminal (not shown) is formed. The connecting member 400 is preferably attached to the PCM 300 by welding.

The fastening grooves 410 of the connection member 400 are oriented side by side in one direction of the PCM 300. Therefore, the plate-shaped electrode terminals of the battery cell as shown in FIG. 1 can be inserted into the fastening groove 410 to be easily fastened.

3 and 4a show perspective views of one exemplary connecting member in a fastening PCM according to the invention, and in FIG. 4b a vertical cross section of line A-A of FIG. 4a is shown.

First, referring to FIG. 3, the connecting member 400 has an integral structure in which a metal plate is bent. That is, the metal plate is cut out in the shape of the connecting member 400 in the drawing, and then the plate portions 402 and 303 of both sides are vertically bent based on the base plate 401 to form sidewalls. In addition, a portion of the base plate 401 is bent inwardly so that an upper plate 404 parallel thereto is formed. Then, the end 405 of the short side plate portion 402 is bent inward, and the long side plate portion 403 is bent inward to form a cover 406 on the top plate 404. . Of course, the bending order of the metal sheet may be partially changed as long as the above structure can be formed.

Hereinafter, for convenience of description, the base plate 401 is referred to as a "lower end surface", the cover 406 is referred to as an "upper end surface", and the upper plate 404 is referred to as a "bend extension part".

4A and 4B, the metal plate constituting the connecting member 400 has a portion extending from the bottom surface 420 to be rolled inward to form an elastic bent portion 430, and a bent extension 440. ) Is in close contact with the inside of the top surface 450. The fastening groove 410 is a close contact between the bent extension 440 and the top surface 450, the plate-shaped electrode terminal (not shown) is inserted into their elastic close contact is made fastening. The bent portion 430 provides elastic fastening of the electrode terminal to the fastening groove 410, and its outer surface is rounded to facilitate insertion of the plate-shaped electrode terminal.

An end portion of the bending extension part 440 extends further to the rear beyond the elastic close contact with the upper end surface 450 and then bends upward to form the pressure head 460. Accordingly, when the pressing head 460 is pressed downward, a close contact portion between the bending extension part 440 and the top surface 450 is opened, and thus the plate-shaped electrode terminal can be easily inserted into the fastening groove 410. have.

An opening 452 having a predetermined size is formed at the rear end of the upper surface 450, and a protrusion 442 that is elastically upwardly protruding is formed at a position corresponding to the opening 452 among the bent extensions 440. The protrusion 442 is inclined in the direction of the fastening groove 410, so that the insertion of the electrode terminal is not significantly disturbed.

While pressing the pressure head 460 downward, the protrusion 442 is also spaced apart from the top surface 450, and a portion of the electrode terminal is positioned on the protrusion 442. Accordingly, when the downward force of the pressing head 460 is released after the insertion of the electrode terminal is completed, the pressing head 460 is raised again by the elastic restoring force of the bent portion 430. Is restored to the position of the opening 452, the electrode terminal interposed therebetween is fastened with a firm coupling force.

As a result, the coupling force of the electrode terminal to the fastening groove 410 of the connecting member 400 can be greatly affected by the elastic force of the bent portion 430, between the bent extension 440 and the bottom surface 420 Compression spring 470 may be additionally installed in the space of FIG. 5.

6A through 6C schematically illustrate a series of assembling processes for connecting a PCM to a battery cell in a battery pack.

First, referring to FIG. 6A, the side sealing part 210 and the upper sealing part 220 of the battery cell 200 are vertically bent upwardly and the electrode terminals 230 and 232 are bent vertically downward again. The upper sealing part 220 and the electrode terminals 230 and 232 are bent as described above, so that the size of the battery pack can be further reduced. It is preferable that the electrode terminals 230 and 232 form a slightly curved surface so that insertion of the PCM (not shown) into the groove for fastening is easy.

As shown in FIG. 6B, the PCM 400 is positioned so that the fastening groove 410 is adjacent to the lower bent electrode terminals 230 and 232 of the battery cell 200, and the pressure head 460 is pressed to fasten it. The dragon groove 410 is further opened.

Then, as shown in FIG. 6C, when the electrode terminals 230 and 232 are inserted into the fastening grooves 410 and release the downward force of the pressure head (not shown), the PCM 400 for the battery cell 200 is released. Connection is achieved.

Although described above with reference to the drawings according to an embodiment of the present invention, those of ordinary skill 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 PCM of the fastening structure according to the present invention includes a connection member having a simple connection structure, which is easy to manufacture, and a welding or soldering process that requires a lot of time and skill in manufacturing a battery pack. The connection of the PCM to the battery cell can be achieved by a simple assembly process, and the connection portion has an effect of providing a high coupling force and a stable electrical connection force.

Claims (14)

A module (PCM) including a protection circuit that controls overcharging, overdischarging, and overcurrent of a battery, wherein a pair of connecting members are attached to a lower end of the PCM in an electrically connected state with the protection circuit. The protective circuit module of the fastening structure consisting of a groove-shaped connection structure that can be fastened by inserting the plate-shaped electrode terminal of the battery cell. According to claim 1, wherein the PCM has a printed circuit board (PCB) structure, the connection member is the bottom surface of the PCB so that the lower end of the PCB can be coupled to the end surface of the electrode terminal of the battery cell is formed Protective circuit module, characterized in that mounted on. The protection circuit module according to claim 1, wherein the connection member is formed on both ends of the bottom surface of the PCM in a hexahedral form, and the fastening grooves are oriented side by side in the width direction of the PCM. The top surface according to claim 1, wherein the connecting member is a top surface whose part (bending extension) is opposite to the bottom surface in a state where an elastic sheet extending from its bottom surface is bent inwardly. Closely in contact with the protective circuit module, characterized in that the elastic close contact between the bent extension and the top surface acts as a fastening groove. The end portion of the bend extension portion is bent upwardly beyond the elastic contact portion with the upper end surface to form the pressure head so as to facilitate insertion of the electrode terminal into the fastening groove. Protective circuit module. According to claim 4, In order to increase the coupling force of the connecting member to the electrode terminal, an opening of a predetermined size is further formed in the rear of the upper end surface, the elastic projection protruding upwardly in the bending extension of the corresponding position A protective circuit module, characterized in that formed. The protection circuit module according to claim 4, wherein an elastic member is further provided between the bottom surface and the bend extension. The protective circuit module according to claim 1, wherein the connection member is attached to the PCM main body by welding. The protection circuit module according to claim 1, wherein the connection member is an integral structure manufactured by bending a metal plate. A connecting member mounted to the protective circuit module according to any one of claims 1 to 9, wherein the metal sheet is cut into a predetermined shape, and then the plate portions (a, b) of both sides of the plate are cut off based on the base plate of the sheet. Each bent vertically to form a sidewall, and a portion of the base plate is bent inwardly so that a top plate parallel to it is formed, and the end of the short side plate portion (a) is bent again to the inside, and the length is long. A connecting member having a structure in which a side plate portion (b) is bent inward to form a cover on the top plate. A battery pack comprising a PCM according to any one of claims 1 to 9 electrically connected to a battery cell. The battery pack according to claim 11, wherein the battery cell is a pouch type battery cell in which a battery assembly of positive electrode / separation membrane / cathode is incorporated in a pouch type case of a laminate sheet including a resin layer and a metal layer. 12. The method of claim 11, wherein the upper sealing portion protruding the electrode terminal of the battery cell vertically bent in close contact with the main body of the battery cell, and then the electrode terminal is vertically bent downwardly inserted into the groove for fastening the PCM. Battery pack, characterized in that by combining. The battery pack as claimed in claim 11, wherein an electrically insulating resin is filled into the battery cell and the PCM by insert injection molding.

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