Abstract:
A battery pack includes a battery cell including an electrode assembly, a case accommodating the battery cell inside the battery pack, an external terminal at an upper outside portion of the case, the external case being electrically connected to the battery cell, the external terminal having a protruding end, a foreign substance receiver at the upper outside portion of the case, the foreign substance receiver being between the protruding end of the external terminal and the case being positioned to trap foreign substances generated at the external terminal, and a magnetic body installed inside the foreign substance receiver, the magnetic body being spaced apart from the external terminal.

Description:
BACKGROUND 
       [0001]    1. Field 
         [0002]    Embodiments relate to a battery pack. 
         [0003]    2. Description of the Related Art 
         [0004]    In general, it may be difficult to adopt a single battery call as a power supply for electric equipment such as a notebook computer, an electronic device, an electric bicycle or an electric scooter. Therefore, a battery pack used as a power supply in such electric equipment or electronic device may include a plurality of battery cells connected in series/parallel. 
       SUMMARY 
       [0005]    According to embodiments, there is provided a battery pack including a battery cell including an electrode assembly, a case accommodating the battery cell inside the battery pack, an external terminal at an upper outside portion of the case, the external terminal being electrically connected to the battery cell and having a protruding end, a foreign substance receiver at the upper outside portion of the case, the foreign substance receiver being between the protruding end of the external terminal and the case and being positioned to trap foreign substances generated at the external terminal, a magnetic body installed inside the foreign substance receiver, the magnetic body being spaced apart from the external terminal. 
         [0006]    The external terminal may be a clip type terminal, and may protrude in a direction toward or above the foreign substance receiver. 
         [0007]    The foreign substance receiver may include a bottom portion shaped as a rectangular plate, and side portions upwardly extending from three edges of the bottom portion, the bottom portion and side portions being integrally formed. 
         [0008]    The foreign substance receiver may have one open side and an open top portion. The protruding end of the external terminal may be positioned above the foreign substance receiver through the one open side. 
         [0009]    The battery pack may further include a circuit board disposed between the external terminal and the case. A support portion for supporting a bottom of the circuit board may be provided at an end of at least one of the side portions of the foreign substance receiver. 
         [0010]    The foreign substance receiver may further include barrier walls upwardly extending to form right angles with respect to the one open side. The foreign substance receiver may include a fixing slit at an exterior side of at least one of the side portions. The fixing slit may be coupled to a protrusion in the interior case such that the foreign substance receiver may be mounted in the interior case. 
         [0011]    The magnetic body may be a rubber magnet. The magnetic body may be adhered to an inside of the foreign substance receiver by an adhesive tape. The magnetic body may be adhered to a top surface of the bottom portion of the foreign substance receiver. 
         [0012]    The battery pack may further include a circuit board disposed between the external terminal and the case. The battery cell and the external terminal may be electrically connected to each other through a wire pattern in the circuit board. The external terminal may be coated with nickel, iron, cobalt, alloys thereof, or combinations thereof. 
         [0013]    The battery pack may further include an external case accommodating the case and the external terminal, the external case having a terminal hole to expose the external terminal to an outside of the battery pack. 
         [0014]    The battery pack may include a plurality of battery cells. 
         [0015]    The battery cell may include a plurality of external terminals, each being a clip type terminal and protruding in a direction toward or above the foreign substance receiver. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    Features will become apparent to those of ordinary skill in the art by describing in detail exemplary embodiments with reference to the attached drawings in which: 
           [0017]      FIG. 1  illustrates a perspective view of an exemplary electronic device having a battery pack according to an embodiment mounted therein; 
           [0018]      FIGS. 2A to 2C  illustrate a perspective view, a plan view and a front view of a battery pack according to an embodiment, and  FIG. 2D  is a cross-sectional view taken along the line D-D′ of  FIG. 2A ; 
           [0019]      FIGS. 3A and 3B  illustrate a perspective view and a plan view of a case, a foreign substance receiver, an external terminal and a circuit board accommodated inside an external case of the battery pack shown in  FIG. 2A ; 
           [0020]      FIG. 4  illustrates a perspective view of an exemplary foreign substance receiver mounted in the case shown in  FIG. 2A ; and 
           [0021]      FIG. 5  illustrates a perspective view of another exemplary foreign substance receiver mounted in the case shown in  FIG. 2A . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Korean Patent Application No. 10-2012-0018726, filed on Feb. 23, 2012, in the Korean Intellectual Property Office, and entitled: “Battery Pack,” is incorporated by reference herein in its entirety. 
         [0023]    Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope thereof to those skilled in the art. 
         [0024]    In the drawing figures, the dimensions of features may be exaggerated for clarity of illustration. Like reference numerals refer to like elements throughout. 
         [0025]      FIG. 1  illustrates a perspective view of an exemplary electronic device having a battery pack according to an embodiment mounted therein. 
         [0026]    Referring to  FIG. 1 , the exemplary electronic device  10 , such as, for example, a power tool, may include a housing  11  having a built-in rotation driver system and a handle  12  extending from the housing  11  in a substantially vertically downward direction. A driver bit  14 , such as, for example, a drill bit, may be fixed to the housing  11  by a holder  13 . The driver bit  14  may be driven by the rotation driver system incorporated in the housing  11 . A switch trigger  15  is provided in the handle  12 . If the switch trigger  15  is pressed, the rotation driver system is driven to rotate the driver bit  14 . 
         [0027]    The battery pack  100  may be mounted at a bottom end of the handle  12 , and the rotation driver system may be driven by the power applied from the battery pack  100 . 
         [0028]    A configuration of the battery pack  100  will now be described with reference to  FIGS. 2A to 2D . 
         [0029]      FIGS. 2A to 2C  illustrate a perspective view, a plan view and a front view of a battery pack according to an embodiment, and  FIG. 2D  is a cross-sectional view taken along the line D-D′ of  FIG. 2A . 
         [0030]    Referring to  FIGS. 2A to 2D , the battery pack  100  may include a battery cell  110 , an interior case  120 , a circuit board  130 , an external terminal  140 , a foreign substance receiver  150  and an external case  160 . 
         [0031]    The battery cell  110  may be a rechargeable secondary battery. For example, a cylindrical lithium secondary battery cell having a high operating voltage of 3.6 V or greater and a high energy density per unit weight may be used as the battery cell  110 . The battery cell  110  may be plural in number. While  FIG. 1D  illustrates four battery cells  110 , in other implementations, other numbers of battery cells  110  may be provided. The plurality of battery cells  110  may have different polarities at their top and bottom surfaces, and adjacent battery cells  110  may connected in series using connection leads or connection plates (not shown). 
         [0032]    Referring to  FIG. 2D , the interior case  120  may have a top interior case portion  121  and a bottom interior case portion  122 . In the interior case  120 , the top interior case portion  121  and the bottom interior case portion  122  may be connected to or disconnected from each other to accommodate the battery cells  110  therein. The interior case  120  may be made of an insulating material such as plastic. In addition, guide rails  121   a  and  122   a  corresponding in shape to the plurality of battery cells  110  may be provided inside the interior case  120 , thereby preventing the battery cells  110  from vibrating inside the interior case  120 . In addition, the top interior case portion  121  may have at least two protruding parts  121   b  upwardly protruding. The protruding part  121   b  of the interior case  120  may be formed at a location corresponding to the edge of the circuit board  130 , but aspects are not limited thereto. 
         [0033]    The circuit board  130  may have a substantially plate-like shape and may be installed on the top interior case portion  121 . The circuit board  130  may be mounted on the protruding part  121   b  upwardly extending from the top interior case portion  121  of the interior case  120 . The circuit board  130  may be spaced apart from the top surface of the interior case  120  by a distance corresponding to a height of the protruding part  121   b.    
         [0034]    The circuit board  130  may be electrically connected to the battery cells  110  accommodated in the interior case  120  through a through-hole (not shown) formed in the interior case  120 . The circuit board  130  may be a printed circuit board having a plate made of a resin, a wire pattern (not shown) and a plurality of electric circuits (not shown). The wire pattern of the circuit board  130  may be a pattern for electrically connecting the battery cells  110  to the external terminal  140 . In addition, the electric circuits of the circuit board  130  may include a circuit (not shown) for controlling charging and discharging of the battery cells  110  and a protection circuit (not shown) for preventing over-charge/over-discharge. 
         [0035]    The external terminal  140  electrically connected to the circuit board  130  may be installed on the circuit board  130 . The external terminal  140  may have a proximal side  140   a  fixed to the circuit board  130  and a distal side  140   b  shaped as a plane and protruding to the outside of the circuit board  130 . An end of the distal side  140   b  of the external terminal  140  may be positioned on the foreign substance receiver  150 . In addition, the external terminal  140  may be electrically connected to the wire pattern formed in the circuit board  130  and may be electrically connected to the battery cells  110  through the wire pattern. The external terminal  140  may be exposed to the outside of the external case  160  through the terminal hole  161   a  formed in the external case  160 . In addition, the external terminal  140  may be formed as a clip type terminal to be engaged with a terminal of the electronic device  10  that may be in the shape of a bar. In addition, the external terminal  140  may include two clips  141  and  142  arranged in a vertical direction to increase a coupling force of the electronic device  10 . The external terminal  140  may be electrically connected to the terminal of the electronic device  10  through the terminal hole  161 . The battery pack  100  may supply power to the electronic device  10  through the external terminal  140 . A configuration of the external terminal  140  is shown in detail in  FIGS. 3A and 3B , which will be described below in detail. 
         [0036]    The foreign substance receiver  150  may be installed at a lower portion of a region where the end of the distal side  140   b  of the external terminal  140  is positioned and may have a predetermined height. A magnetic body  170  may be mounted within the foreign substance receiver  150 . A configuration of the foreign substance receiver  150  is shown in detail in  FIGS. 3A and 3B , which will be described below in detail. 
         [0037]    The external case  160  may have a top exterior case portion  161  and a bottom exterior case portion  162 . The external case  160  accommodates the interior case  120 , the circuit board  130 , the external terminal  140  and the foreign substance receiver  150  as the top exterior case portion  161  and the bottom exterior case portions  162  are combined with each other. The top exterior case portion  161  may be formed with a step such that a top surface of one side is vertically higher than a top surface of the other side. The circuit board  130 , the external terminal  140  and the foreign substance receiver  150  may positioned inside the exterior case  160  below the higher side of the top exterior case portion  161 . The terminal hole  161  a may be provided at a protruding edge to expose the external terminal  140  accommodated within the external case  160  to the outside of the external case  160  by the step formed in the external case  160 . The terminal hole  161   a  may be an “L” shaped slit formed at the protruding edge. 
         [0038]    In addition, one or more fixing protrusions  161   b  and  161   c  may be provided in the top case  161  for coupling and fixing the top external case portion  161  to the electronic device  10 . The fixing protrusions  161   b  and  161   c  may be formed on the outer periphery of the terminal hole  161   a  to be symmetrical to each other with respect to the terminal hole  161 , but in other implementations, other configurations are possible. 
         [0039]      FIGS. 3A and 3B  illustrate a perspective view and a plan view of the internal case  120 , the foreign substance receiver  150 , the external terminal  140  and the circuit board  130  accommodated inside the external case  160  of the battery pack  100  shown in  FIG. 2A .  FIG. 4  is a perspective view illustrating an exemplary foreign substance receiver  150  mounted in the exterior case  160  shown in  FIG. 2A . 
         [0040]    Hereinafter, configurations of the circuit board  130 , the external terminal  140  and the foreign substance receiver  150  will be described with reference to  FIGS. 3A ,  3 B, and  4 . 
         [0041]    The circuit board  130  may be mounted and fixed to the protruding part  121   b  formed on the interior case  120 . The circuit board  130  may be spaced apart from the top surface of the top interior case  121  portion by the protruding part  121   b  by a distance corresponding to a height of the protruding part  121   b.  The circuit board  130  may have a substantially rectangular-plate shape having one edge  130   a,  another edge  130   b  parallel to the one edge  130   a,  and two side edges  130   c  connecting the one edge  130   a  to the other edge  130   b  in parallel. The protruding part  121   b  of the interior case  120  may support the two side edges  130   c  from the bottom. The protruding part  121   b  may also support the one edge  130   a  of the circuit board  130 , but in other implementations, other configurations are possible. 
         [0042]    The external terminal  140  mounted on the circuit board  130  may protrude toward the other edge  130   b  of the circuit board  130 . In addition, the foreign substance receiver  150  may be mounted at a lower portion of the other edge  130   b  of the circuit board  130 . The foreign substance receiver  150  may be mounted at a region corresponding to the lower portion of the external terminal  140  protruding to the other edge  130   b  of the circuit board  130 . 
         [0043]    The proximal side  140   a  of the external terminal  140  may be fixed to the circuit board  130  and the distal side  140   b  thereof may be formed as an elastic clip type terminal. The distal side  140   b  of the external terminal  140  may be an elastic clip type terminal in the shape of tongs. The clip type external terminal  140  may include two clips  141  and  142  arranged in a vertical direction. The vertically arranged clips  141  and  142  may increase a coupling force with respect to a bar-shaped terminal of an electronic device. The external terminal  140  may be plated with a magnetic metal such as nickel (Ni), iron (Fe), cobalt (Co), or alloys thereof. 
         [0044]    In addition, the foreign substance receiver  150  may have a bottom portion  151  shaped as a rectangular plate and side portions  152  upwardly extending from three edges of the bottom portion  151  to have a predetermined height. The bottom portion  151  and the side portions  152  may be integrally formed. The side portions  152  and the bottom portion  151  together may form a “U” shape. In addition, the foreign substance receiver  150  may be configured to include one open side  150   a,  that is a side without a side surface, and an open top portion. The one open side  150   a  of the foreign substance receiver  150  may be positioned under the other side  130   b  of the circuit board  130 . The distal side  140   b  of the external terminal  140  may be positioned above the foreign substance receiver  150  through the one open side  150   a  of the foreign substance receiver  150 . In addition, the one open side  150   a  of the foreign substance receiver  150  may further include a partial side surface portion  153  for preventing foreign substances induced into the foreign substance receiver  150  from escaping from the foreign substance receiver  150  through the one open side  150   a.    
         [0045]    The end of the side portion  152  of the foreign substance receiver  150  may be formed stepwise, and the end may correspond to a support portion  152   b  for supporting the other side  130   b  of the circuit board  130 . The support portion  152   b,  that is, the end of the side portion  152  of the foreign substance receiver  150 , may be lower than the remainder of the side portion  152  of the foreign substance receiver  150 . The support portion  152   b  may be formed to the same height as the protruding part  121   b  formed on the interior case  120 . The support portion  152   b  of the foreign substance receiver  150  may support and fix the other side  130   b  of the circuit board  130  from the bottom. 
         [0046]    In addition, the magnetic body  170  may be installed within the foreign substance receiver  150 . The magnetic body  170  may be adhered to a top surface of the bottom portion  151  of the foreign substance receiver  150  using an adhesive tape  171 . The magnetic body  170  may be made of a rubber magnet, such as a soft plastic magnet. 
         [0047]    A fixing slit  152   a  may be formed on the side portions of the foreign substance receiver  150  that face each other. The foreign substance receiver  150  may be fixed to the interior case  120  by the fixing slit  152   a.  A protrusion  121   c  corresponding to the fixing slit  152   a  may further be formed in the interior case  120 . The protrusion  121   c  may be formed on the side portion of the protruding part  121   b  formed in the interior case  120 . The side portions  152  of the foreign substance receiver  150  facing each other may be supported using the protrusion  121   c . The foreign substance receiver  150  may be slidably attached to/detached from the top surface of the interior case  120  using the fixing slit  152   a.    
         [0048]    The foreign substance receiver  150  may receive the foreign substance generated due to abrasion between the external terminal  140  of the battery pack  100  and the terminal of the electronic device  10  when the battery pack  100  is repeatedly attached to and detached from the electronic device  10 . In addition, the foreign substance receiver  150  may have the magnetic body  170  provided therein. Accordingly, even if the battery pack  100  is moved, it may be possible to prevent the foreign substance created by abrasion of the external terminal from being introduced into the battery pack  100  by attaching and fixing the foreign substance on a surface of the magnetic body  170  using a magnetic force. The foreign substance between the terminals having magnetic and conductive properties may be prevented from being introduced into the battery pack  100  by the foreign substance receiver  150  and the magnetic body  170 . Therefore, an electric short circuit due to the introduction of the conductive foreign substance may be prevented. 
         [0049]      FIG. 5  illustrates a perspective view of another exemplary foreign substance receiver  250  mounted in the case shown in  FIG. 2A . 
         [0050]    Referring to  FIG. 5 , the foreign substance receiver  250  may be substantially the same as the foreign substance receiver  150  shown in  FIG. 4  in view of configurations of the bottom and side portions. Therefore, the following description will focus on differences between the foreign substance receiver  150  shown in  FIG. 4  and the foreign substance receiver  250  shown in  FIG. 5 , that is, barrier walls  254  of the foreign substance receiver  250 . The barrier walls  254  may extend from the one open side of the foreign substance receiver  250  at a predetermined angle to be integrally formed with the side portion  152  and the bottom portion  151 . The barrier walls  254  may be formed perpendicular to the one open side of the foreign substance receiver  250  to the same height as the side portion  152 . A support portion  254   a  for supporting the other side  130   b  of the circuit board  130  may further be formed at an end of each of the barrier walls  254 . The inside of the foreign substance receiver  250  may be divided into multiple compartments according to the number of the barrier walls  254  formed in the foreign substance receiver  250 . A magnetic body  270  may be adhered to a top surface of the bottom portion  151  in each of the multiple compartments of the foreign substance receiver  250  using an adhesive tape  271 . The magnetic body  270  may be formed to correspond in shape to the bottom portion  151  of each of the multiple compartments of the foreign substance receiver  250 , and may be adhered to the top surfaces of the respective bottom portions  151  divided by the barrier walls  254 . 
         [0051]    By way of summation and review, when the battery pack used in the electronic device is repeatedly attached to or detached from a charger or electronic device to be charged or to drive the tool, the external terminals of the battery pack may be abraded. The external terminal may have conductivity. Accordingly, when foreign substance of the external terminal is introduced into the battery pack, a safety problem, such as an electric short circuit, may be generated. 
         [0052]    The embodiments may provide a battery pack that can improve safety by preventing foreign substance generated due to abrasion of external terminals from being induced into the battery pack. In more detail, a foreign substance receiver may be provided at a lower portion of the external terminal of the battery pack. Accordingly, conductive foreign substances, which may be produced due to abrasion of the external terminal occurring when the battery pack is repeatedly attached to or detached from other devices, can be prevented from being induced into the battery pack. 
         [0053]    In the battery pack according to embodiments, a magnetic body may be attached to the inside of a foreign substance receiver and the external terminal may be plated with a magnetic metal. Accordingly, the foreign substance abraded from the external terminal may have a magnetic property and may be adhered to the magnetic body provided inside the foreign substance receiver. Therefore, even if the battery pack is moved, the safety of the battery pack can be improved by preventing an electric short circuit that may otherwise be generated when the foreign substance is induced into the battery pack. 
         [0054]    Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope as set forth in the following claims.