Connecting tab of battery pack, coupling structure between the connecting tab and wire, and coupling method thereof

Embodiments of the present invention provide a connecting tab of a battery pack, which allows a wire to be firmly coupled to a battery cell or a protective circuit module, a coupling structure between the connecting tab and a wire, and coupling method thereof. In one embodiment of the present invention, the connecting tab coupled to a battery cell or a protective circuit module includes a first conductive layer electrically connected to the battery cell or the protective circuit module, and a second conductive layer formed on the first conductive layer and coupled to a wire. The second conductive layer may include a pair of coupling protrusions upwardly protruding for connection of the wire. A solder may further be formed on the coupling protrusions and the wire.

DETAILED DESCRIPTION OF THE INVENTION

1. Technical Field

Embodiments of the present invention relate to a connecting tab of a battery pack, a coupling structure between the connecting tab and a wire, and coupling method thereof.

2. Background Art

In general, it is often difficult to use a single battery cell as a power supply for electronic equipment or electrically powered equipment such as a notebook computer, an electrically powered tool, an electric bicycle or an electrically powered scooter. Therefore, a battery pack used as a power supply for such electronic equipment or electrically powered equipment includes a plurality of battery cells connected in series/parallel.

In order to control charging and discharging operations of the battery cells or to prevent the battery cells from being over-charged or over-discharged, the battery pack may further include a protective circuit module. A conductive wire is connected between each of the battery cells and the protective circuit module.

SUMMARY

Embodiments of the present invention provide a connecting tab of a battery pack, which allows a wire to be firmly coupled to a battery cell or a protective circuit module, a coupling structure between the connecting tab and a wire, and coupling method thereof.

Embodiments of the present invention also provide a connecting tab of a battery pack, which can quickly and safely couple a wire to be firmly coupled to a battery cell or a protective circuit module, a coupling structure between the connecting tab and a wire, and coupling method thereof.

According to a first embodiment of the present invention, a connecting tab coupled to a battery cell or a protective circuit module includes a first conductive layer electrically connected to the battery cell or the protective circuit module, and a second conductive layer formed on the first conductive layer and coupled to a wire.

In this first embodiment, a connecting region through which the first conductive layer and the second conductive layer are connected to each other may further be formed at each of an end of the first conductive layer and an end of the second conductive layer.

In this first embodiment, the first conductive layer and the second conductive layer may be made of the same material or different materials each including a clad.

In this first embodiment, the second conductive layer may include a pair of coupling protrusions upwardly protruding for connection of the wire. A solder may further be formed on the coupling protrusions and the wire. A hole or a recess may be formed in the second conductive layer for the purpose of preventing the solder from excessively spreading.

According to a second embodiment of the present invention, a coupling method may include preparing a connecting tab including a first conductive layer and a second conductive layer connected to each other through a connecting region, and a pair of coupling protrusions upwardly protruding from the second conductive layer, attaching the connecting tab to a battery cell or a protective circuit module, and coupling a wire to the pair of coupling protrusions of the connecting tab.

Allowing the second conductive layer and the pair of coupling protrusions to be positioned in the second embodiment on the first conductive layer by bending the connecting region may further be performed between the preparing of the connecting tab and the attaching of the connecting tab.

The coupling of the wire may be performed in the second embodiment such that the pair of coupling protrusions are clamped after the wire is inserted into the pair of coupling protrusions.

The coupling of the wire may be performed in the second embodiment such that a solder is formed on each of the pair of coupling protrusions and the wire after the wire is inserted into the pair of coupling protrusions.

The coupling of the wire may be performed in the second embodiment such that the pair of coupling protrusions is clamped and a solder is formed on each of the pair of coupling protrusions and the wire after the wire is inserted into the pair of coupling protrusions.

Since the connecting tab of a battery pack according to an embodiment of the present invention includes a more planar first conductive layer, the first conductive layer is more easily welded to the battery cell or the protective circuit module. In addition, since a second conductive layer and a pair of fixing protrusions are formed on the first conductive layer, a wire can be more easily coupled to the second conductive layer and the pair of fixing protrusions.

In the connection tab of a battery pack according to another embodiment of the present invention, a wire is coupled to a pair of coupling protrusions provided in the connection tab. In another embodiment of the present invention, after coupling the wire to the pair of coupling protrusions, a solder may be formed. In an alternative embodiment of the present invention, after coupling the wire to the pair of coupling protrusions, protrusions are clamped and a solder is formed. Therefore, the coupling structure between the connecting tab and the wire can allow the connecting tab and the wire to be firmly coupled to each other.

Further, with the coupling structure, even when the temperature of the coupling structure rises due to a large current flowing through the wire, resulting in melting of the solder, the wire coupled to the pair of coupling protrusions inhibits the wire from being easily separated from the connecting tab.

In the coupling method of the wire and the connecting tab of the battery pack according to another embodiment of the present invention, the connecting tab is connected to a battery cell or a protective circuit module and the wire is coupled to a pair of coupling protrusions provided in the connection tab. In an alternative embodiment of the present invention, after coupling the wire to the pair of coupling protrusions, a solder may be formed. In a further embodiment of the present invention, after coupling the wire to the pair of coupling protrusions, the coupling protrusions are clamped. Furthermore, after clamping the coupling protrusions, a solder may be formed. Therefore, the time required for coupling the connecting tab and the wire to each other is shortened. In addition, since there is no dangerous factor for the entire coupling time, improved working safety is ensured.

In another embodiment, the invention comprises a connector for electrically connecting a wire to at least one battery to a protective circuit module. In this embodiment, the connector comprises a first connecting member having a first and a second surface that electrically connects to the at least one battery or the protective circuit module via the first surface. In this embodiment, the connector further comprises a second connecting member having a first and second surface that is coupled to the first connecting member so that the first surface of the second connecting member is positioned adjacent the second surface of the first connecting member and wherein the wire is electrically coupled to the second connecting member.

In another embodiment, the invention comprises a method securing a wire to either at least one battery or a protective circuit module. In this embodiment, the method comprises positioning a second connecting member with respect to a first connecting member so that a first side of the second connecting member is positioned proximate the second side of the first connecting member where the first and second members are electrically interconnected. In this embodiment, the method further comprises electrically connecting the first connecting member to the at least one battery or the protection circuit module and electrically connecting a wire to the second side of the second connecting member.

DETAILED DESCRIPTION

Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments are described below in order to explain the present invention by referring to the figures.

FIG. 1is a circuit diagram schematically illustrating a battery pack according to an embodiment of the present invention, andFIG. 2is a perspective view schematically illustrating the battery pack shown inFIG. 1.

As shown inFIGS. 1 and 2, the battery pack100includes a plurality of battery cells110, connecting tabs120A,120B and120C, a protective circuit module130, and wires141A and141B.

Each of the battery cells110may be a rechargeable battery. In an exemplary embodiment, the battery cell110may be any one selected from a lithium ion battery, a lithium polymer battery, a lithium ion polymer battery, and equivalents thereof, but aspects of the present invention are not limited thereto. In addition, the battery cell110may have any one shape selected from a cylindrical shape, a prismatic shape, a pouch-type shape, equivalents thereof, but aspects of the present invention are not limited thereto.

The connecting tabs120A,120B and120C electrically connect the battery cells110to one another in series or parallel. AlthoughFIGS. 1 and 2illustrate that a plurality of battery cells110are connected to one another in the 5-series-2-parallel configuration by the connecting tabs120A,120B, and120C, aspects of the present invention are not limited thereto.

The protective circuit module130is electrically connected to the battery cells110, and controls charging and discharging operations of the battery cells110. Here, the protective circuit module130includes a positive electrode pad131A and a negative electrode pad131B to be electrically connected to the battery cells110. The protective circuit module130controls the battery cells110not to be over-charged, and include various electronic elements133, such as ICs, transistors, resistors, capacitors, or the like, for controlling the over-charging operation of the battery cells110. A connector134may be installed in the protective circuit module130to allow the protective circuit module130to be connected to a charger (not shown) or a load (not shown).

The wire141A and141B electrically connect the battery cells110to the protective circuit module130. The wires141A and141B are wrapped by insulating coatings141aand141b, respectively. The wire includes a positive electrode wire141A and a negative electrode wire141B. The positive electrode wire141A connects a connecting tab120A connected to a positive electrode terminal111of one having the highest potential among the battery cells110to a positive electrode pad131A of the protective circuit module130. That is to say, one end of the positive electrode wire141A is coupled, connected or soldered to the connecting tab120A, and the other end of the positive electrode wire141A is soldered to the positive electrode pad131A. The negative electrode wire141B connects a connecting tab120B connected to a negative electrode terminal112of one having the lowest potential among the battery cells110to a negative electrode pad131B of the protective circuit module130. That is to say, one end of the negative electrode wire141B is coupled, connected or soldered to the connecting tab120B, and the other end of the negative electrode wire141B is soldered to the negative electrode pad131B.

Here, the connecting tab120A connected to a positive electrode terminal111of the battery cell110having the highest potential may have a two-layered structure including a first conductive layer121and a second conductive layer122. That is to say, the first conductive layer121is welded to the positive electrode terminal111of the battery cell110, and the positive electrode wire141A is coupled, connected or soldered to the second conductive layer122. In addition, the connecting tab120B connected to the battery cell110having the lowest potential has the same configuration as the connecting tab120A, a detailed description thereof will be omitted.

Meanwhile, the other connecting tab120C, to which the positive electrode wire141A or the negative electrode wire141B is not coupled, may have a single-layered structure including only one conductive layer. The connecting tab120C including only one conductive layer is welded to the positive electrode terminal111or the negative electrode terminal112of the battery cell110, thereby electrically connecting the plurality of battery cells110to one another in series and parallel.

Each of the connecting tab120C having a single-layered structure and the connecting tabs120A and120B having a two-layered structure may be any one selected from nickel, nickel-plated copper, and equivalents thereof, but aspects of the present invention are not limited thereto. Each of the connecting tabs120A,120B, and120C may be formed of a metal clad including nickel and copper. In alternative embodiments, only the second conductive layer122of each of the two-layered connecting tabs120A and120B may be formed of a metal clad. As well known in the related art, the metal cladding may be formed by welding, rolling, casting or extruding rather than plating. Thus, the metal cladding may have newly improved properties compared to its base material, for example, improved wettability of the solder.

As described above, in the battery pack100according to the embodiment of the present invention, since the connecting tabs120A,120B, and120C, specifically, the connecting tabs120A and120B coupled, connected or soldered with the wires141A and141B, have a two-layered structure, rather than a single-layered structure, a coupling force between each of the battery cells110and each of the connecting tabs120A and120B may be enhanced. Further, a coupling force between each of the wires141A and141B and each of the connecting tabs120A and120B may also be enhanced. The reason of the foregoing is that the first conductive layer121of the connecting tab120A is first coupled to the battery cell110and the wire141A is then coupled to the second conductive layer122, for example. In other words, coupling between the first conductive layer121and the battery cell110is not interfered by coupling between the second conductive layer122and the wire141A.

The connecting tab120B coupled or soldered with the wire141B is disposed on the bottom surface of the battery cell110B (seeFIG. 2). That is to say, the connecting tab120B is attached to a negative electrode of the battery cell110B disposed on the bottom surface thereof. Therefore, the connecting tab120B is not seen fromFIG. 2because it is shielded by the battery cell110B. However, since the connecting tab120B has the same configuration and shape as the connecting tab120A, it is not separately illustrated in the drawing.

FIG. 3is a perspective view schematically illustrating a battery pack according to another embodiment of the present invention.

As shown inFIG. 3, in the battery pack101according to the embodiment of the present invention, connecting tabs220A and220B may be coupled to a protective circuit module130. That is to say, the connecting tab220A is connected to a positive electrode pad131A of the protective circuit module130, while the connecting tab220B is connected to a negative electrode pad131B of the protective circuit module130. Further, a positive electrode wire141A is connected or soldered to the connecting tab220A, while a negative electrode wire141B is connected or soldered to the connecting tab220B. Since the connecting tabs220A and220B are substantially the same as the aforementioned connecting tabs120A and120B, detailed descriptions of the connecting tabs220A and220B will be omitted.

As described above, according to the illustrated embodiment, the connecting tabs220A and220B are applied not only to the battery cells110but also to the protective circuit module130, thereby further enhancing a coupling force between each of the wires141A and141B and the protective circuit module130.

FIG. 4is a partially perspective view illustrating a coupling structure according to an embodiment of the present invention for coupling a wire and a connecting tab of a battery pack.

As shown inFIG. 4, the connecting tab120A of the battery pack100shown inFIG. 1includes a first conductive layer121welded to the battery cell110, a second conductive layer122formed on the first conductive layer121, a connecting region123through which the first conductive layer121and the second conductive layer122are connected to each other, a pair of coupling protrusions124formed on the second conductive layer122and upwardly protruding by a predetermined length, and a pressing part125formed on the first conductive layer121and pressing the second conductive layer122. Here, the connecting region123and the pressing part125are formed in opposite directions. In addition, the pair of coupling protrusions124are disposed such that a distance therebetween upwardly decreases.

In the connecting tab120A, the first conductive layer121may be welded to a positive electrode terminal111of the battery cell110, and a conductive wire141A may be coupled to the pair of coupling protrusions124provided in the second conductive layer122. In addition, a solder150may further be formed on each of the conductive wire141A and coupling protrusions124.

FIG. 5is a partially perspective view illustrating a coupling structure according to another embodiment of the present invention for coupling a wire and a connecting tab of a battery pack.

As shown inFIG. 5, the connecting tab220A of the battery pack101shown inFIG. 3includes a first conductive layer121welded to the protective circuit module130, a second conductive layer122formed on the first conductive layer121, a connecting region123through which the first conductive layer121and the second conductive layer122are connected to each other, a pair of coupling protrusions124formed on the second conductive layer122and upwardly protruding by a predetermined length, and a pressing part125formed on the first conductive layer121and pressing the second conductive layer122.

In addition, in the connecting tab220A, the first conductive layer121may be welded to a positive electrode pad131A of the protective circuit module130, and a conductive wire141A may be coupled to the pair of coupling protrusions124provided in the second conductive layer122. In addition, a solder150may further be formed on each of the conductive wire141A and coupling protrusions124.

The connecting tab120A connected to the battery cell110and the connecting tab220A connected to the protective circuit module130may have substantially the same configuration. In the following, it should be noted that the connecting tab120A, the coupling structure between the connecting tab120A and the wire141A, and the coupling method of the connecting tab120A and the wire141A, which will be described below, are all applied to the previous embodiments.

FIG. 6Ais a plan view of the coupling structure between a wire and a connecting tab according to an embodiment of the present invention,FIG. 6Bis a cross-sectional view taken along the line6b-6bofFIG. 6A,FIG. 6Cis a cross-sectional view taken along the line6c-6cofFIG. 6A, andFIG. 6Dis another cross-sectional view taken along the line6c-6cofFIG. 6A.

Referring toFIGS. 6A through 6C, the connecting tab120A includes a includes a first conductive layer121connected to the battery cell110or the protective circuit module130, a second conductive layer122formed on the first conductive layer121, a connecting region123through which the first conductive layer121and the second conductive layer122are connected to each other, a pair of coupling protrusions124formed on the second conductive layer122and upwardly protruding by a predetermined length, and a pressing part125formed on the first conductive layer121and pressing the second conductive layer122.

The first conductive layer121includes a substantially planar body121a, and a substantially planar extension121bextending in opposite directions from the body121a. In addition, recesses121cand121dare formed in the body121aand the extension121b, respectively. During welding, a welding tool is placed on each of the recesses121cand121d. Thus, the connecting tab120A is easily welded to the battery cell110or the protective circuit module130. A cut portion121eis formed between the body121aand the extension121b. Therefore, heat generated by the welding tool is concentrated in the recesses121cand121dwithout spreading during welding. Accordingly, welding efficiency can be further enhanced. The first conductive layer121may be made of any one selected from nickel, nickel-plated copper, and equivalents thereof, but aspects of the present invention are not limited thereto.

The second conductive layer122is substantially planar and is formed on the first conductive layer121. The second conductive layer122may be formed to be slightly narrower than the body121aof the first conductive layer121, but aspects of the present invention are not limited thereto. Holes122aeach having a predetermined size may be formed at opposite sides of the second conductive layer122. That is to say, the second conductive layer122may have the holes122aformed at opposite sides of the wire141A. A surface of the first conductive layer121is exposed upwardly through the holes122a. The holes122aaccommodate a solder material excessively formed when forming the solder150, thereby preventing the solder150from flowing to the outside of the connecting tab120A. Like the first conductive layer121, the second conductive layer122may also be made of any one selected from nickel, nickel-plated copper, and equivalents thereof, but aspects of the present invention are not limited thereto.

The connecting region123allows one end of the first conductive layer121and the second conductive layer122to be connected to each other. In addition, the connecting region123is substantially bent and may be made of the same material as the first conductive layer121or the second conductive layer122.

The pair of coupling protrusions124upwardly protrude from the second conductive layer122by a predetermined length. The pair of coupling protrusions124is formed such that a portion of the second conductive layer122is cut and bent upwardly. The holes122aare also formed in the second conductive layer122by cutting. The pair of coupling protrusions124may be made of substantially the same material as the second conductive layer122. In addition, the pair of coupling protrusions124may be formed at opposite sides of the wire141A. Further, the pair of coupling protrusions124becomes closer to each other upwards. Therefore, the pair of coupling protrusions124is configured to roughly wrap the wire141A. Accordingly, the wire141A is firmly coupled, fastened or connected to the connecting tab120A. In addition, the pair of coupling protrusions124may be clamped by means of a separate tool. In other words, top ends of the pair of coupling protrusions may closely contact each other to then be clamped by, for example, a plier. Accordingly, a coupling force between the pair of coupling protrusions and the wire141A is further enhanced.

The pressing part125is upwardly bent from the first conductive layer121, and is further bent in a horizontal direction to then press an end of the second conductive layer122. The pressing part125is formed at the opposite side of the connecting region123. In addition, the pressing part125is formed at a region corresponding to the one end of the wire141A. Therefore, the pressing part125limits a coupling depth of the wire141A. Accordingly, the coupling depth of the wire141A relative to the connecting tab120A is controlled to be kept uniformly.

Meanwhile, the wire141A is inserted into a space between the pair of coupling protrusions124and then coupled or connected to the pair of coupling protrusions124. In addition, in order to enhance a coupling force between the wire141A and the connecting tab120A, the solder150may further be formed in each of the wire141A and the pair of coupling protrusions124. Further, the wire141A is inserted into the space between the pair of coupling protrusions124and then coupled or connected to the pair of coupling protrusions124, followed by clamping the pair of coupling protrusions124. Following the clamping of the pair of coupling protrusions124, the solder150may further be formed in the wire141A and the pair of coupling protrusions124.

The solder150may cover portions of the first conductive layer121and the second conductive layer122as well as the wire141A and the pair of coupling protrusions124. A surplus solder material remaining after being used in forming the solder150may be accommodated in the holes122aformed in the second conductive layer122. To this end, a width of each of the holes122ais larger than that of each of the coupling protrusions124, so that the surplus solder material may be easily accommodated in the holes122a. In such a manner, the wire141A is coupled, fastened or connected to the pair of coupling protrusions124formed in the connecting tab120A and is wrapped by the solder150, thereby further enhancing the coupling force between the wire141A and the connecting tab120A

As shown inFIG. 6D, the recess122b, instead of the hole122a, may be formed in the second conductive layer122. Since the surplus solder material is accommodated in the recess122b, the recess122balso prevents the surplus solder material from flowing to the outside of the connecting tab120A.

As described above, according to one embodiment, the wire141A is coupled, fastened or connected to the pair of coupling protrusions124formed in the connecting tab120A. In addition, according to another embodiment of the present invention, after coupling the wire141A to the pair of coupling protrusions124provided in the connecting tab120A, the protrusions124may be clamped. In an alternative embodiment of the present invention, after coupling the wire141A to the pair of coupling protrusions124provided in the connecting tab120A, a solder150may be formed in each of the wire141A and the pair of coupling protrusions124. In a further embodiment of the present invention, after coupling the wire141A to the pair of coupling protrusions124provided in the connecting tab120A and clamping the pair of coupling protrusions124, a solder150may be formed in each of the wire141A and the pair of coupling protrusions124. Therefore, according to embodiments of the present invention, the coupling force between the connecting tab120A and the wire141A can be further enhanced.

Further, according to an embodiment of the present invention, even when the solder150is melted by a high-temperature heat generated due to a large current flowing through the wire141A, the wire141A coupled to the pair of coupling protrusions124may prevent the wire141A from being easily separated from the connecting tab120A.

FIGS. 7A through 7Fare perspective view sequentially illustrating a coupling method of a wire using a connecting tab, according to an embodiment of the present invention.

Referring toFIGS. 7A through 7F, the coupling method according to the embodiment of the present invention for coupling a connecting tab120A and a wire141A of a battery pack100include preparing the connecting tab120A, bending the connecting tab120A, electrically connecting the connecting tab120A to the battery cell and/or the protective circuit module, and coupling the wire141A to the connecting tab120A.

The coupling method may further include clamping a pair of coupling protrusions124provided in the connecting tab120A.

The coupling method may further include forming a solder150in the wire141A. Here, the solder150may be formed after the coupling of the wire141A. Alternatively, the solder150may be formed after the clamping of the pair of coupling protrusions124.

As shown inFIG. 7A, the preparing of the connecting tab120A may include preparing a connecting tab120A including a first conductive layer121, a second conductive layer122, a connecting region123, a pair of coupling protrusions124and a pressing part125. Here, the first conductive layer121and the second conductive layer122are formed to be substantially planar. The connecting region123is slightly recessed along the boundary line of the first conductive layer121and the second conductive layer122so as to be easily bent. Since the connecting region123is yet to be bent, the pair of coupling protrusions124are formed to be directed to the bottom side, rather than the upper side. In addition, a pressing part125formed at the opposite side of the connecting region123is also yet to be bent upwardly, the pressing part125and the first conductive layer121are substantially parallel to each other.

In addition, since recesses121cand121dfor welding, respectively formed in a body121aand an extension121bforming the first conductive layer121, a cut portion121efor preventing heat from spreading, and holes122aformed in the second conductive layer122, for preventing a solder material from excessively spreading are substantially the same as described above, detailed descriptions thereof will be omitted.

As shown inFIG. 7B, the bending of the connecting tab120A includes bending the first conductive layer121or the second conductive layer122to allow the second conductive layer122to be positioned on the first conductive layer121. The connecting region123, through which the first conductive layer121and the second conductive layer122are connected to each other, is bent, thereby allowing the second conductive layer122to be positioned on the first conductive layer121. Here, a pressing part125protruding from the first conductive layer121in a horizontal direction is also upwardly bent. That is to say, the pressing part125is bent in a substantially “U” shape. In other words, the pressing part125is bent such that one end of the pressing part125covers one end of the second conductive layer122, thereby preventing a gap from being created between the first conductive layer121and the second conductive layer122. As described above, the pressing part125allows the first conductive layer121and the second conductive layer122to closely contact each other. In addition, the pressing part125limits a coupling depth of the wire141A, which will later be described. Further, in the bending of the connecting tab120A, the holes122aformed in the second conductive layer122are allowed to be positioned on the first conductive layer121. Therefore, a predetermined region of the first conductive layer121corresponding to the hole122ais exposed to the upper side.

As shown inFIG. 7C, electrically connecting the connecting tab120A to the battery cell and/or the protective circuit module includes electrically connecting the first conductive layer121of the connecting tab120A to the battery cell110and/or the protective circuit module (not shown). For example, the first conductive layer121of the connecting tab120A is poisoned on the battery cell110. More specifically, the body121aand the extensions121bof the first conductive layer121are positioned on the battery cell110. The welding tool240is positioned on the recesses121cand121dthat are already formed on the body121aand the extensions121b. Energy of the welding tool240is transferred to the recesses121cand121dand battery cell110, and then the recesses121cand121dare welded to the battery cell110. Here, the cut portion121eformed between the body121aand the extension121bmakes the heat generated by the welding tool240concentrate to the recesses121cand121dwithout spreading during welding. Accordingly, welding efficiency can be further enhanced.

As shown inFIG. 7D, the coupling of the wire141A includes coupling the wire141A to a space between the second conductive layer122and the pair of coupling protrusions124. Here, since the coupling depth of the wire141A is limited by the pressing part125, the wire141A is coupled to the pair of coupling protrusions124by a predetermined length. In such a manner, the wire141A is coupled, fastened or connected to the connecting tab120A.

As described above, the coupling method of the connecting tab120A and the wire141A according to the embodiment of the present invention may be completed by the coupling of the wire141A.

Alternatively, the coupling method for coupling the connecting tab120A and the wire141A may be completed after additionally performing forming a solder after the coupling of the wire141A. In other words, the solder is formed in each of the wire141A and the pair of coupling protrusions124wrapping the wire141A, thereby allowing the wire141A to be more firmly coupled to the connecting tab120A. Here, the solder may be formed to cover portions of the first conductive layer121and the second conductive layer122as well as the wire141A and the pair of coupling protrusions124. Here, a surplus of the solder that is excessively used is accommodated in the hole122aformed in the second conductive layer122, thereby preventing the excessively used solder from flowing to the outside of the connecting tab120A.

As shown inFIG. 7E, the clamping of the pair of coupling protrusions124includes clamping the pair of coupling protrusions124formed outside the wire141A. For example, top ends of the pair of coupling protrusions124are clamped by a tool230, such as a plier, thereby allowing the top ends of the pair of coupling protrusions124to make contact with the wire141A more closely.

In such a manner, the coupling method according to the illustrated embodiment of the present invention may be completed immediately after the clamping of the pair of coupling protrusions124. That is to say, even if the solder is not formed, the coupling protrusions124allow the wire141A to be firmly coupled, fastened or connected to the connecting tab120A.

As shown inFIG. 7F, the forming of the folder150includes forming the solder150in each of the wire141A and the pair of coupling protrusions124. Here, the solder150may be formed in portions of the first conductive layer121and the second conductive layer122as well as the wire141A and the pair of coupling protrusions124. Since the solder material excessively used in the forming of the solder150is accommodated in the hole122aformed in the second conductive layer122, thereby preventing the surplus solder material from flowing to the outside of the connecting tab120A. In such a manner, the wire141A is coupled, fastened or connected to the pair of coupling protrusions124formed in the connecting tab120A and is wrapped by the solder150, thereby further enhancing a coupling force between the wire141A and the connecting tab120A.

As described above, in the coupling method of the wire141A and the connecting tab120A of the battery pack100according to the embodiment of the present invention, the connecting tab120A is primarily coupled to the wire141A using the coupling protrusions124provided in the connection tab120A and secondarily coupled to the wire141A using the solder150, thereby shortening the entire coupling time and eliminating dangerous factors for the entire coupling time, ultimately ensuring improved working safety.

Although a connecting tab of a battery pack, a coupling structure between the connecting tab and a wire, and coupling method thereof according to a few embodiments of the present invention have been shown and described, it should be understood by those of ordinary skill in the art that various replacements, modifications and changes in the form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.