Abstract:
A battery pack including a can having an opening; an electrode assembly accommodated in the can; a cap plate closing the opening and including a protruding anchor portion; and an insulation plate having an anchor hole accommodating the anchor portion, wherein the anchor hole is a slot and is configured to allow movement of the anchor portion within the anchor hole when pressure is applied to the can and the cap plate.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of Korean Patent Application No. 10-2014-0016797, filed on Feb. 13, 2014, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    One or more embodiments of the present invention relate to battery packs. 
         [0004]    2. Description of the Related Art 
         [0005]    Developments in wireless Internet and wireless communication technology prompted a fast growth of the market for portable electronic equipment such as mobile phones, game consoles, portable multimedia players (PMP), mpeg audio layer-3 (MP3) players, smartphones, smart pads, electronic book terminals, flexible tablet computers, and wearable medical equipment. 
         [0006]    For example, mobile computers are compact and easy to carry, and are widely used for both work and personal purposes. Mobile computers generally include a battery pack as a power supply device. A typical battery pack may include a plurality of unit batteries that may be repeatedly charged and discharged in order to provide sufficient power output. 
         [0007]    Recent technological developments have increased the demand for battery packs suitable for many types of mobile electronic appliances, including, for example, curved battery packs suitable for curved mobile electronic appliances. 
       SUMMARY 
       [0008]    One or more embodiments of the present invention are directed to a battery pack that maintains stability during curving. 
         [0009]    Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments. 
         [0010]    According to one or more embodiments of the present invention, a battery pack includes: a can having an opening; an electrode assembly accommodated in the can; a cap plate closing the opening and including a protruding anchor portion; and an insulation plate having an anchor hole accommodating the anchor portion, wherein the anchor hole is a slot and is configured to allow movement of the anchor portion within the anchor hole when pressure is applied to the can and the cap plate. 
         [0011]    The anchor hole may be asymmetrical with respect to a central line along a lengthwise direction of the insulation plate. 
         [0012]    The cap plate may have a first concave lateral surface and a second convex lateral surface, and the first and second lateral surfaces may be substantially aligned with each other. 
         [0013]    A distance from the central line of the insulation plate to an end of the anchor hole near the second lateral surface may be smaller than a distance from the central line of the insulation plate to an end of the anchor hole near the first lateral surface. 
         [0014]    A plurality of anchor holes may be formed and may include: a first anchor hole at a first side of the insulation plate spaced from a center of the can; and a second anchor hole at a second side of the insulation plate opposite to the first side and spaced from the center of the can. 
         [0015]    A first distance between the center of the can and the first anchor hole and a second distance between the center of the can and the second anchor hole may be different. 
         [0016]    The first distance may be greater than the second distance. 
         [0017]    In the first anchor hole, a line passing through the center of the first anchor hole in a lengthwise direction is at a predetermined angle to the central line of the insulation plate. 
         [0018]    The insulation plate may include a mounting portion accommodating a terminal plate, wherein a distance between a side of the mounting portion adjacent to the first anchor hole and an inner edge of the first anchor hole decreases from the second lateral surface toward the first lateral surface. 
         [0019]    A width of the first anchor hole may increase from the second lateral surface toward the first lateral surface. 
         [0020]    The anchor portion may include a first anchor portion accommodated in the first anchor hole and a second anchor portion accommodated in the second anchor hole. 
         [0021]    A cross-section of the first anchor portion may be greater than a cross-section of the second anchor portion. 
         [0022]    The cap plate may include a first cap plate that electrically insulates the electrode assembly and a second cap plate on the first cap plate, wherein the anchor portion is on at least one of the first cap plate and the second cap plate. 
         [0023]    The anchor hole may include an open end accommodating the anchor portion and coupling the anchor portion to the insulation plate. 
         [0024]    The first lateral surface and the second lateral surface of the cap plate may have different curvature radii. 
         [0025]    A difference between the curvature radii of the first lateral surface and the second lateral surface may be about 10 mm to about 30 mm. 
         [0026]    The cap plate may be welded to the can from an upper portion of the cap plate along an external surface of the cap plate. 
         [0027]    According to one or more embodiments of the present invention, a battery pack includes: a can having an opening; an electrode assembly accommodated in the can; a cap plate closing the opening of the can, the cap plate including a protruding anchor portion; and an insulation plate having an anchor hole accommodating the anchor portion, wherein the cap plate is curved and includes a first concave lateral surface and a second convex lateral surface, wherein a shortest distance from the first lateral surface to an end of the anchor hole nearer the first lateral surface is smaller than a shortest distance between the second lateral surface and an end of the anchor hole nearer the second lateral surface. 
         [0028]    According to one or more embodiments of the present invention, a method of manufacturing a battery pack, includes: placing an electrode assembly inside a can having an opening; fixing an insulation plate to a cap plate and installing the cap plate to cover the opening of the can; bonding the cap plate and the can by welding along the edge of the opening of the can; and curving the can and the cap plate by applying pressure to the can and the cap plate, wherein the cap plate includes a protruding anchor portion, and the insulation plate includes an anchor hole accommodating the anchor portion, and the anchor portion moves within the anchor hole when applying a pressure to the can and the cap plate. 
         [0029]    The bonding of the cap plate and the can by welding may include bonding the cap plate and the can by welding the cap plate from an upper portion of the cap plate along an external surface of the cap plate. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which: 
           [0031]      FIG. 1  is a partially exploded perspective view illustrating a battery pack according to an embodiment of the present invention; 
           [0032]      FIG. 2  is a partially exploded perspective view illustrating the battery pack of 
           [0033]      FIG. 1 ; 
           [0034]      FIG. 3  is a bottom view schematically illustrating a cap plate of  FIG. 2 ; 
           [0035]      FIGS. 4 and 5  are bottom plan views illustrating an insulation plate of  FIG. 2  according to an embodiment of the present invention; 
           [0036]      FIG. 6  is a plan view illustrating a modified insulation plate of  FIG. 2  according to another embodiment of the present invention; and 
           [0037]      FIG. 7  is a plan view illustrating a modified insulation plate of  FIG. 2  according to another embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0038]    Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. Further, the use of “may” when describing embodiments of the present invention refers to “one or more embodiments of the present invention. 
         [0039]    As the inventive concept allows for various changes and many different forms, particular embodiments will be illustrated in the drawings and described in detail in the written description. The advantages and features of the present invention and methods of achieving the advantages and features will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. The invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. 
         [0040]    It will also be understood that although the terms “first”, “second”, etc. may be used herein to describe various components, these components should not be limited by these terms. These components are only used to distinguish one component from another. 
         [0041]    Singular expressions, unless defined otherwise, include plural expressions. 
         [0042]    It will be further understood that the terms “comprise” and/or “have” used herein specify the presence of stated features or components, but do not preclude the presence or addition of one or more other features or components. 
         [0043]    It will also be understood that when an element such as a layer, an area, or a component is referred to as being “on” or “on the top of” another element, it can be directly on or directly on the top of the other element, or intervening layers, areas, or components may also be present. 
         [0044]    In the embodiments below, an x-axis, a y-axis, and a z-axis are not limited to three axes on a rectangular coordinates system but may be construed as including these axes. For example, an x-axis, a y-axis, and a z-axis may be at right angles or may also indicate different directions from one another, which are not at right angles. 
         [0045]    In the drawings, for convenience of description, sizes of elements may be exaggerated or contracted. In other words, since sizes and thicknesses of components in the drawings are arbitrarily illustrated for convenience of description, the following embodiments are not limited thereto. 
         [0046]      FIG. 1  is a schematic exploded perspective view illustrating a battery pack  100  according to an embodiment of the present invention.  FIG. 2  is a schematic exploded perspective view illustrating the battery pack  100  of  FIG. 1 .  FIG. 3  is a bottom view schematically illustrating a cap plate  130  of  FIG. 2 . 
         [0047]    Referring to  FIGS. 1 through 3 , the battery pack  100  may include a can  110 , an electrode assembly  120 , a cap plate  130 , an insulation plate  140 , a terminal plate  150 , and an electrode pin  160 . The battery pack  100  may be a rechargeable secondary battery such as, for example, a lithium-ion battery. 
         [0048]    The case  110  may have an approximately hexahedral shape with an opening in an upper portion thereof, and the can  110  may be curved. The case  110  may be formed of a metallic material, in order to provide rigidity. For example, the can  110  may be formed of aluminum or an aluminum alloy, but the material for forming the can  110  is not limited thereto. After the electrode assembly  120  is inserted into the can  110  through the opening of the can  110 , the opening may be encapsulated using the cap plate  130 . 
         [0049]    The electrode assembly  120  may include a first electrode layer  121 , a second electrode layer  122 , and a separator  123  between the first electrode layer  121  and the second electrode layer  122 . The electrode assembly  120  may have a structure in which a plurality of first electrode layers  121 , second electrode layers  122 , and separators  123  are stacked. For example, the electrode assembly  120  may have a jelly-roll structure in which the first electrode layers  121 , the second electrode layers  122 , and the separators  123  are wound around one another, but the structure of the electrode assembly  120  is not limited thereto. Herein, solely for convenience of description, a jelly-roll structure of the electrode assembly  120  will be described. 
         [0050]    The first electrode layer  121  may be one of a positive electrode film and a negative electrode film. When the first electrode layer  121  is a positive electrode film, the second electrode layer  122  may be a negative electrode film, and when the first electrode layer  121  is a negative film, the second electrode layer  122  may be a positive electrode film. In other words, the first electrode layer  121  and the second electrode layer  122  may have different polarities and neither is limited to a specific polarity. However, solely for convenience of description, the first electrode layer  121  formed of a positive electrode film and the second electrode layer  122  formed of a negative electrode film will be described. 
         [0051]    The first electrode layer  121  may include a first metal collector and a first active material portion formed by coating a first active material on the surface of the first metal collector. Likewise, the second electrode layer  122  may include a second metal collector and a second active material portion formed by coating a second active material on the surface of the second metal collector. 
         [0052]    When the first electrode layer  121  is a positive electrode film, the first metal collector may be a positive electrode collector, and the first active material portion may be a positive active material portion. Accordingly, the second electrode layer  122  is a negative electrode film, and the second metal collector may be a negative electrode collector, and the second active material portion may be a negative active material portion. The material and structure of each of the positive electrode collector, the positive electrode active material portion, the negative electrode collector, and the negative electrode active material portion may be any material and structure suitable for use in a secondary battery, and thus detailed descriptions of the materials and structures of the positive electrode collector, the positive electrode active material portion, the negative electrode collector, and the negative electrode active material portion will not be provided here. 
         [0053]    The separator  123  may be a porous polymer layer such as a polyethylene film or a polypropylene film, and may be in the form of a woven or nonwoven fiber including, without limitation, polymer fibers. In addition, the separator  123  may include ceramic particles, and may be formed of a polymer solid electrolyte. The separator  123  may be a separately formed film or may be formed by forming a nonconductive porous layer on the first electrode layer  121  or the second electrode layer  122 . 
         [0054]    In one embodiment, the separator  123  electrically separates the first electrode layer  121  and the second electrode layer  122  from each other, and the form of the separator  123  may be different from the form of the first electrode layer  121  or the second electrode layer  122 . 
         [0055]    A first electrode plate  125  and a second electrode plate  127  having different polarities may be included. In one embodiment, the first and second electrode plates  125  and  127  enable the electrode assembly  120  to be electrically connected to the outside source. In one embodiment, the first electrode plate  125  is electrically connected to the first electrode layer  121  to have a positive polarity, and the second electrode plate  127  is electrically connected to the second electrode layer  122  to have a negative polarity. 
         [0056]    In one embodiment, the cap plate  130  hermetically seals the opening of the can  110  to protect the electrode assembly  120  installed in the can  110 . The cap plate  130  may include a first cap plate  131  that closes the opening of the can  110  and a second cap plate  132  on the first cap plate  131 . 
         [0057]    Similar to the can  110 , the cap plate  130  may be formed of aluminum or a metallic material such as an aluminum alloy. A region where the cap plate  130  and the can  110  contact may be welded from an upper portion of the cap plate  130  along an external surface of the cap plate  130  so as to bond the cap plate  130  and the can  110 , thereby tightly sealing the can  110 . 
         [0058]    In one embodiment, the cap plate  130  includes first lateral surfaces  131   a  and  132   a  that are concave (i.e. curved inward) and second lateral surfaces  131   b  and  132   b  that are convex (i.e. curved outward), and the first lateral surfaces and the second lateral surfaces are substantially aligned with each other, such that the concave portion of the first lateral surface corresponds to the convex portion of the respective second lateral surface. In one embodiment, the first lateral surfaces include a first cap plate inner surface and a second cap plate inner surface. The second lateral surfaces include a first cap plate outer surface and a second cap plate outer surface. In particular, the first cap plate inner surface is formed to correspond to the second cap plate inner surface, and the first cap plate outer surface is formed to correspond to the second cap plate outer surface. The first lateral surfaces  131   a  and  132   a  of the cap plate  130  may be concave, and the second lateral surfaces  131   b  and  132   b  of the cap plate  130  may be convex. A curvature radius of the first lateral surfaces  131   a  and  132   a  may be different from the curvature radius of the second lateral surfaces  131   b  and  132   b . In one embodiment, the difference between the curvature radii of the first lateral surfaces  131   a  and  132   a  and the second lateral surfaces  131   b  and  132   b  may be from about 10 mm to about 30 mm. If the difference in the curvature radii is less than 10 mm, the can  110  may be too narrow to install the electrode assembly  120 . If the difference in the curvature radii is greater than 30 mm, a relatively large external force has to be applied to the can  110  and the cap plate  130  in order to form a curvature in the battery pack  100 , thus increasing the risk of damage to the battery  100  due to the external force, as well as increasing energy consumption. 
         [0059]    In one embodiment, the first cap plate  131  electrically insulates the electrode assembly  120  from the outside. In one embodiment, the first cap plate  131  is formed of an insulating material and includes a first hole  135  through which the first electrode plate  125  passes and a second hole  137  through which the second electrode plate  127  passes. The first hole  135  and the second hole  137  are spaced apart from each other so as not to contact each other, and to separate the first electrode plate  125  and the second electrode plate  127  having different polarities. 
         [0060]    The first cap plate  131  may include a rib  131   c  protruding from the lateral surface of the first cap plate  131  and supporting the second cap plate  132 . When the second cap plate  132  is mounted on the first cap plate  131 , rib  131   c  may act to hold the first cap plate  131  and the second cap plate  132  together and to prevent (or reduce) separation of the first cap plate  131  from the second cap plate  132 . 
         [0061]    The second cap plate  132  may be installed on the first cap plate  131  to be electrically connected to the first electrode plate  125 . In addition, the electrode pin  160  may be positioned on the second cap plate  132 . The electrode pin  160  may be inserted into terminal through-holes  139   a ,  142 , and  151  respectively formed in the second cap plate  132 , the insulation plate  140 , and the terminal plate  150 , and the electrode pin  160  may be electrically connected to the second electrode plate  127  of the electrode assembly  120 . When the electrode pin  160  is inserted into the terminal through-hole  139   a  of the second cap plate  132 , the electrode pin  160  is electrically insulated from the second cap plate  132  via a gasket  139 . 
         [0062]    The first electrode plate  125  may be electrically connected to the second cap plate  132 , and the second electrode plate  127  may electrically contact the terminal plate  150 and thus may be electrically connected to the electrode pin  160 . Since the first electrode plate  125  and the second electrode plate  127  have different polarities, the second cap plate  132  and the electrode pin  160  respectively connected to the first electrode plate  125  and the second electrode plate  127  also have different polarities. 
         [0063]    In order to prevent a short circuit between the electrode pin  160  and the second cap plate  132 , the gasket  139  may be positioned between the electrode pin  160  and the second cap plate  132 . The gasket  139  may be formed of an insulating material and may prevent an electrical short circuit between the electrode pin  160  and the second cap plate  132 . 
         [0064]    In one embodiment, the terminal through-hole  139   a  is formed in a center portion of the second cap plate  132 . When the electrode pin  160  is inserted into the terminal through-hole  139   a , the electrode pin  160  is electrically insulated from the second cap plate  132  by the gasket  139 , and electrically contacts the terminal plate  150 . 
         [0065]    An electrolyte solution inlet  138  may be formed in the second cap plate  132 . In embodiments where the can  110  has been hermetically sealed, an electrolyte solution is injected into the can  110  through the electrolyte solution inlet  138 . After the electrolyte solution has been injected, the electrolyte solution inlet  138  may be sealed by using a sealing stopper. 
         [0066]    The cap plate  130  may include a first anchor portion  133  and a second anchor portion  134  that are protruding to support the insulation plate  140 . The first anchor portion  133  and the second anchor portion  134  may be formed on at least one of the first cap plate  131  and the second cap plate  132  and may be respectively inserted into a first anchor hole  143  and a second anchor hole  144  of the insulation plate  140 , such that the first anchor portion  133  and second anchor portion  134  are disposed between the first cap plate  131  and the second cap plate  132 . Hereinafter, solely for convenience of description, the focus will be on an embodiment in which the first anchor portion  133  and second anchor portion  134  are formed on the second cap plate  132 . 
         [0067]    The first anchor portion  133  and second anchor portion 134  may be included to support the insulation plate  140  within the cap plate  130 . In one embodiment, the insulation plate  140  is disposed on the second electrode plate  127  in order to insulate the second electrode plate  127  that is electrically connected to terminal plate  150  from the second cap plate  132 . The first anchor portion  133  is positioned away from a center and towards the edge of the can  110 , and the second anchor portion  134  is positioned near the center of the can  110 . In one embodiment, a cross-section of the second anchor portion  134  may be greater than a cross-section of the first anchor portion  133 , so that the insulation plate  140  may be firmly supported within the cap plate  130  in the center portion of the can  110 . 
         [0068]    The insulation plate  140  may be positioned between the first cap plate  131  and the second cap plate  132  and may be formed of the same insulation material as the gasket  139 , but the material for forming the insulation plate  140  is not limited thereto. The terminal through-hole  142 , through which the electrode pin  160  is inserted, is formed in the insulation plate  140  at a position substantially corresponding to the position of the terminal through-hole  139   a  of the second cap plate  132 . In one embodiment, a mounting portion  141  is formed on a lower surface of the insulation plate  140 . The mounting portion  141  may correspond to the size of the terminal plate  150 , such that the terminal plate  150  can be mounted on the insulation plate  140 . 
         [0069]    In one embodiment, the terminal plate  150  is formed of a nickel (Ni) alloy and is coupled to the lower surface of the insulation plate  140 . The terminal through-hole  151 , into which the electrode pin  160  is inserted, is formed in the terminal plate  150  at a position substantially corresponding to the position of the terminal through-hole  139   a  of the second cap plate  132 . In one embodiment, the electrode pin  160 , after passing through the terminal through-hole  139   a  of the second cap plate  132 , is inserted into the terminal through-hole  151 . Since the electrode pin  160  is electrically insulated from the second cap plate  132  via the gasket  139  and is electrically coupled to the terminal plate  150 , the terminal plate  150  may be electrically insulated from the second cap plate  132  and electrically connected to the electrode pin  160 . 
         [0070]      FIGS. 4 and 5  are exploded bottom plan views illustrating the insulation plate  140  of  FIG. 2 , according to one embodiment of the present invention.  FIG. 4  shows the structure of the insulation plate  140  and the first and second anchor portions  133  and  134  before the cap plate  130  is molded by applying an external force, and  FIG. 5  shows the structure of the first and second anchor portions  133  and  134  of the insulation plate  140  after the cap plate  130  is curvedly molded by applying an external force. 
         [0071]    Referring to  FIGS. 4 and 5 , according to one embodiment of the present invention, the insulation plate  140  may include a mounting portion  141  on which the terminal plate  150  is installed, a terminal through-hole  142  through which the electrode pin  160  is inserted, a first anchor hole  143  into which the first anchor portion  133  is inserted, and a second anchor hole  144  into which the second anchor portion  134  is inserted. In one embodiment, the first anchor hole  143  and the second anchor hole  144  may each be open at one end, and the first anchor portion  133  and the second anchor portion  134  may be inserted into the open ends of the first anchor hole  143  and second anchor hole  144 , respectively, to be coupled to the insulation plate  140 . 
         [0072]    In one embodiment, the first anchor hole  143 , formed at a first side of the insulation plate  140 , is positioned away from the center of the can  110 , and the second anchor hole  144 , formed at a second side of the insulation plate  140  opposite to the first side of the insulation plate  140 , is positioned near the center of the can  110 . 
         [0073]    Accordingly, when the insulation plate  140  is placed between the first cap plate  131  and the second cap plate  132 , a first distance S 1  between the center of the can  110  and the first anchor hole  143  is greater than a second distance S 2  between the center of the can  110  and the second anchor hole  144 . 
         [0074]    The first anchor hole  143  may be in the form of a slot such and may be larger in diameter than the first anchor portion  133 , such that the first anchor portion  133  may move along the edge of the first anchor hole  143 , when the can  110  and the cap plate  130  are being curved. In other words, when pressure is applied to the can  110  and the cap plate  130 , the second anchor portion  134  is substantially fixed inside the second anchor hole  144 , and the first anchor portion  133  may move along the edge of first anchor hole  143  between the first and second lateral surfaces, without interference from the insulation plate  140 . 
         [0075]    The first anchor hole  143  may be asymmetrically formed with respect to a central line A of the insulation plate  140  along a lengthwise direction of the insulation plate  140 , as illustrated in  FIGS. 4 and 5 . In other words, the distance from the central line A of the insulation plate  140  to the second end of the first anchor hole  143  closer to the second lateral surfaces  131   b  and  132   b  may be smaller than the distance from the central line A of the insulation plate  140  to the first end of the first anchor hole  143  closer to the first lateral surfaces  131   a  and  132   a . Accordingly, the first anchor hole  143  may extend toward the first lateral surfaces  131   a  and  132   a , and the first anchor portion  133  may move along the edge of the first anchor hole  143  toward the first lateral surfaces  131   a  and  132   a . In one embodiment, the shortest distance dl between the first lateral surfaces  131   a  and  132   a  and the first end of the first anchor hole  143  may be greater than the shortest distance d 2  between the second lateral surfaces  131   b  and  132   b  and the second end of the first anchor hole  143 . 
         [0076]    As illustrated in  FIG. 5 , the central line A of the insulation plate  140  and a central line B extending along a lengthwise direction of the first anchor hole  143  may be at a predetermined angle. In addition, the width of the first anchor hole  143  may gradually increase from the second lateral surfaces  131   b  and  132   b  toward the first lateral surfaces  131   a  and  132   a . Accordingly, the first anchor portion  133  can easily move toward the first lateral surfaces  131   a  and  132   a  along the edge of the first anchor hole  143 , when the cap plate  130  is curved. In one embodiment, the shortest distance 
         [0077]    G between a lateral surface  145  of the mounting portion  141  that is adjacent to the first anchor hole  143  and the inner edge of the first anchor hole  143  may gradually decrease from the second lateral surfaces  131   b  and  132   b  to the first lateral surfaces  131   a  and  132   a.    
         [0078]    In one embodiment, the battery pack  100  may be formed by manufacturing each of the respective elements for the battery pack  100  in a curved form and then assembling these elements. Alternatively, a flat battery pack may be assembled first and then an external force may be applied to the battery pack  100  to form the battery pack  100  having a curved form. Hereinafter, solely for convenience of description, the focus will be on a method of manufacturing a curved battery pack  100  by applying pressure to the flat battery pack  100 . 
         [0079]    In one embodiment, the electrode assembly  120  may be placed inside the can  110  through an opening in the can  110 . The insulation plate  140  may be fixed to the cap plate  130 , and the cap plate  130  together with the insulation plate  140  may be installed on the opening of the can  110 . The cap plate  130  and the can  110  may be bonded by welding along the edges of the opening of the can  110 , and then pressure. may be applied to the can  110  and the cap plate  130  to curve the can  110  and the cap plate  130 . 
         [0080]    When bonding the cap plate  130  and the can  110  by welding, the cap plate  130  may be welded from an upper portion of the cap plate  130  along an external surface of the cap plate  130 . A welding instrument and the cap plate  130  may be arranged to be perpendicular to each other, or the welding instrument may be obliquely placed at a predetermined angle with respect to the cap plate  130 . By bonding the cap plate  130  and the can  110  in the same plane and arranging the welding instrument at a predetermined height, welding time may be reduced to thereby increase operation efficiency. 
         [0081]    In embodiments where the pressure is applied to the can  110  and the cap plate  130 , the first anchor portion  133  protruding from the second cap plate  132  is inserted into the first anchor hole  143  of the insulation plate  140 , and the first anchor portion  133  moves along the edge of the first anchor hole  143 . The second anchor portion  134  is substantially fixed by the second anchor hole  144 . 
         [0082]    In embodiments where the first anchor portion  133  is guided along the edge of the first anchor hole  143 , the resulting battery pack  100  including the insulation plate  140  may maintain stability when the pressure is applied to the external surface of the battery pack  100  to curvedly form the battery pack  100 . 
         [0083]    In addition, when the first anchor hole  143  in which the first anchor portion  133  may move is formed, damage and separation of the insulation plate  140 , that may occur when the pressure is applied to the external surface of the battery pack  100 , may be minimized or reduced. 
         [0084]      FIG. 6  is a plan view illustrating an insulation plate  240  according to another embodiment of the present invention. The insulation plate  240  is a modified example of the insulation plate  140  of  FIG. 2 . Hereinafter, like reference numerals as above denote like elements. 
         [0085]    Referring to  FIGS. 1 through 3  and  6 , a battery pack according to the embodiment of the present invention illustrated in  FIG. 6  may include a can  110 , an electrode assembly  120 , a cap plate  130 , an insulation plate  240 , a terminal plate  150 , and an electrode pin  160 . The battery pack according to the present embodiment is the same as the battery pack according to the embodiment illustrated in  FIGS. 1 through 3 , except for the shapes of a first anchor hole  243  and a second anchor hole  244  of the insulation plate  240  and thus, the description of the repeated elements will not be provided again and should be apparent from the description provided above in connection with the previously discussed embodiment. 
         [0086]    The insulation plate  240  may include a mounting portion  241  on which the terminal plate  150  is installed, a terminal through-hole  124  through which the electrode pin  160  is inserted, a first anchor hole  243  into which a first anchor portion  233  is inserted, and a second anchor hole  244  into which a second anchor portion  234  is inserted. In one embodiment, the first anchor hole  243  and the second anchor hole  244  may each be open at one end, and the first anchor portion  233  and the second anchor portion  234  may be inserted into the open ends of the first anchor hole  243  and the second anchor hole  244 , respectively, to be coupled to the insulation plate  240 . 
         [0087]    The second anchor hole  244  may be in the form of a slot, such that the second anchor portion  234  may move along the edge of the second anchor hole  244 . In other words, when the pressure is applied to the can  110  and the cap plate  230  to curve the can  110  and the cap plate  230 , the first anchor portion  233  may be substantially fixed by the first anchor hole  243 , and the second anchor portion  234  may move toward a first lateral surface  230   a  of the cap plate  230  along the edge of the second anchor hole  244  without interference by the insulation plate  240 . 
         [0088]    The second anchor hole  244  may be asymmetrically formed with respect to a central line A of the insulation plate  240  along a lengthwise direction of the insulation plate  240 , as illustrated in  FIG. 6 , to extend toward the first lateral surface  230   a . In other words, the distance from the central line A of the insulation plate  240  to the second end of the second anchor hole  244  closer to the second lateral surface  230   b  may be smaller than the distance from the central line A of the insulation plate  240  to the first end of the second anchor hole  244  closer the first lateral surface  230   a . Accordingly, the second anchor hole  244  may extend toward the first lateral surface  230   a , and the second anchor portion  234  may move along the edge of the second anchor hole  244  toward the first lateral surface  230   a . In one embodiment, the shortest distance d 3  between the first lateral surfaces  230   a  and the first end of the second anchor hole  244  may be greater than the shortest distance d 4  between the second lateral surface  230   b  and the second end of the second anchor hole  244 . 
         [0089]    The battery pack according to the present embodiment is formed by using the same or similar method as the method of manufacturing the battery pack  100  described above, except for the difference in the structure and position of the insulation plate  240  based on the shape of the first and second anchor holes  243  and  244  via which the first and second anchor portions  233  and  234  are guided when the pressure is applied to the external surface of the battery pack. Thus, the description of the repeated elements and/or steps will not be provided again and should be apparent from the description provided above in connection with the previously discussed embodiment. 
         [0090]    In embodiments where an external force is applied to the battery pack, the second anchor portion  234  protruding from the cap plate  230  is inserted into the second anchor hole  244  of the insulation plate  240  and moves along the edge of the second anchor hole  244 . In one embodiment, the first anchor portion  233  is substantially fixed by the first anchor hole  243 . 
         [0091]    In embodiments where the second anchor portion  234  is guided along the edge of the second anchor hole  244 , the resulting battery pack including the insulation plate  240  may maintain stability when the pressure is applied to the external surface of the battery pack to curvedly form the battery pack. 
         [0092]    In addition, when the second anchor hole  244  in which the second anchor portion  234  may move is formed, damage and separation of the insulation plate  140 , that may occur when the pressure is applied to the external surface of the battery pack, may be minimized or reduced. 
         [0093]      FIG. 7  is a plan view illustrating an insulation plate  340  according to another embodiment of the present invention. The insulation plate  340  is a modified example of the insulation plate  140  of  FIG. 2 . Hereinafter, like reference numerals as above denote like elements. 
         [0094]    Referring to  FIGS. 1 through 3  and  7 , a battery pack according to the embodiment of  FIG. 7  may include a can  110 , an electrode assembly  120 , a cap plate  130 , an insulation plate  340 , a terminal plate  150 , and an electrode pin  160 . The battery pack of the present embodiment is the same as the battery packs of the embodiments described above, except for the shapes of a first anchor hole  343  and a second anchor hole  344  of the insulation plate  340 . Thus, the description of the repeated elements will not be provided again and should be apparent from the description provided above in connection with the previously discussed embodiments. 
         [0095]    The insulation plate  340  may include a mounting portion  341  on which the terminal plate  150  is installed, a terminal through-hole  342  through which the electrode pin  160  is inserted, the first anchor hole  343  into which a first anchor portion  333  is inserted, and the second anchor hole  344  into which a second anchor portion  334  is inserted. In one embodiment, the first anchor hole  343  and the second anchor hole  344  may each be open at one end, and the first anchor portion  333  and the second anchor portion  334  may be inserted into the open ends of the first anchor hole  343  and the second anchor hole  344 , respectively, to be coupled to the insulation plate  340 . 
         [0096]    The first anchor hole  343  may be formed as the first anchor hole  143  of the embodiment of  FIGS. 4 and 5 , and the second anchor hole  344  may be formed as the second anchor hole  244  of the embodiment of  FIG. 6 . 
         [0097]    Thus, when the battery pack is being curved, the first anchor portion  333  may move along the edge of the first anchor hole  343 , and at the same time, the second anchor portion  334  may move along the edge of the second anchor hole  344 . 
         [0098]    In embodiments where the first and second anchor portions  333  and  334  are respectively guided along the edges of the first and second anchor holes  343  and  344 , the resulting battery pack including the insulation plate  340  may maintain stability when the pressure is applied to the external surface of the battery pack to curvedly form the battery pack. 
         [0099]    In addition, when the first and second anchor holes  343  and  344 , along which the first and second anchor portions  333  and  334  may move, are formed, damage and separation of the insulation plate  340 , that may occur when the pressure is applied to the external surface of the battery pack, may be minimized or reduced. 
         [0100]    According to embodiments of the present invention, modifying the shape of the battery pack to form a curvature in the battery pack corresponding to the shape of the respective electronic device, may improve space use efficiency of the electronic device. 
         [0101]    The battery pack according to embodiments of the present invention may be curved by applying a bending force, thereby minimizing deformation of the insulation plate and maintaining the stability of the battery pack. 
         [0102]    While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims and equivalents thereof.