Abstract:
A battery pack includes a battery cell unit including a plurality of terminals for transmitting signals and current; an outer cover covering an upper portion of the battery cell unit to shield the terminals from surrounding factors; a flexible circuit board unit between the outer cover and the battery cell unit and contacting the terminals, the flexible circuit board unit including a first portion extending outward through a side of the outer cover in the first direction, a second portion bent from the first portion and around the edge of the outer cover, and a third portion bent from the second portion in a second direction, the third portion forming an angle with the upper surface of the outer cover; and a fixing part on the outer cover and accommodating the third portion of the flexible circuit board unit.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of Korean Patent Application No. 10-2014-0048878, filed on Apr. 23, 2014, in the Korean Intellectual Property Office, the entire content of which is incorporated herein by reference. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    One or more embodiments of the present invention are directed to a battery pack. 
         [0004]    2. Description of the Related Art 
         [0005]    The development of wireless communications increased the demand for small and portable electronic devices that are equipped with batteries and can be used when a power outlet is not available A battery pack may be made up of rechargeable unit cells in order to deliver sufficient output power. 
       SUMMARY 
       [0006]    One or more embodiments of the present invention are directed to a battery pack. 
         [0007]    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. 
         [0008]    According to one or more embodiments of the present invention, a battery pack includes a battery cell unit including a plurality of terminals; an outer cover covering an upper portion of the battery cell unit; a flexible circuit board unit between the outer cover and the battery cell unit and contacting the terminals, the flexible circuit board unit including a first portion extending outward through a side of the outer cover in the first direction, a second portion bent from the first portion and around an edge of the outer cover, and a third portion bent from the second portion in a second direction, the third portion forming an angle with the upper surface of the outer cover, and a fixing part on the outer cover and accommodating the third portion of the flexible circuit board unit. 
         [0009]    The outer cover may include a pullout slot through which the flexible circuit board unit may extend outward. 
         [0010]    The fixing part may form a right angle with the upper surface of the outer cover. 
         [0011]    The fixing part may include: a guide portion protruding from the upper surface of the outer cover in the second direction; a lateral portion bent from the guide portion; and a support portion bent from the lateral portion. 
         [0012]    The guide portion may be spaced from and may face the support portion. 
         [0013]    A distance between the guide portion and the support portion may be different from a thickness of a part of the third portion of the flexible circuit board unit. 
         [0014]    The distance between the guide portion and the support portion may be greater than the thickness of the part of the third portion of the flexible circuit board unit. 
         [0015]    The support portion may include: a first support portion; and a second support portion facing the first support portion. 
         [0016]    A shortest distance between the first and second support portions may be smaller than a width of the part of the third portion of the flexible circuit board unit. 
         [0017]    The support portion may be spaced from the upper surface of the outer cover. 
         [0018]    The distance between the upper surface of the outer cover and the support portion may be different from a thickness of the second portion of the flexible circuit board unit. 
         [0019]    The distance between the upper surface of the outer cover and the support portion may be greater than the thickness of the second portion of the flexible circuit board unit. 
         [0020]    The battery pack may further include a label surrounding the battery cell unit. 
         [0021]    A portion of the label may extend toward the upper surface of the outer cover so as to shield the side of the outer cover through which the flexible circuit board unit extends outward. 
         [0022]    The flexible circuit board unit may include: a contact part contacting the terminals; a cable part coupled to the contact part; and a connector part coupled to an end of the cable part and configured to be connected to an external device. 
         [0023]    According to one or more embodiments of the present invention, a battery pack includes: a unit cell; a protective circuit module electrically connected to the unit cell and including a plurality of terminals; an outer cover on the protective circuit module; a flexible circuit board unit between the outer cover and the protective circuit module and contacting the terminals, the flexible circuit board unit including a first portion extending outward through a side of the outer cover in the first direction, a second portion bent from the first portion and around an edge of the outer cover, and a third portion bent from the second portion in a second direction, the third portion forming an angle with the upper surface of the outer cover; and a fixing part formed on the outer cover and forming an angle with the upper surface of the outer cover, the fixing part securing a portion of the flexible circuit board unit while allowing for the movement of the portion of the flexible circuit board unit. 
         [0024]    The fixing part may include: a guide portion protruding from the upper surface of the outer cover in the second direction; a lateral portion bent from the guide portion; and a support portion bent from the lateral portion. 
         [0025]    The guide portion may be spaced from and may face the support portion. 
         [0026]    A distance between the guide portion and the support portion may be greater than a thickness of a part of the third portion of the flexible circuit board unit. 
         [0027]    The support portion may be spaced from the upper surface of the outer cover, and the distance between the support portion and the upper surface of the outer cover may be greater than the thickness of the second portion of the flexible circuit board unit. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    These and/or other aspects will become apparent from the following description of embodiments, taken in conjunction with the accompanying drawings in which: 
           [0029]      FIG. 1  is a perspective view illustrating a battery pack according to an embodiment of the present invention; 
           [0030]      FIG. 2  is a partially exploded perspective view illustrating the battery pack of  FIG. 1 ; 
           [0031]      FIG. 3  is a perspective view illustrating an outer cover of  FIG. 2 ; 
           [0032]      FIG. 4  is an enlarged perspective view illustrating a fixing part of  FIG. 3 ; 
           [0033]      FIG. 5  is a perspective view illustrating a protective circuit module and a flexible circuit board unit of  FIG. 2 ; 
           [0034]      FIG. 6  is a perspective view illustrating one step of positioning the flexible circuit board unit on the fixing part of  FIG. 3 ; and 
           [0035]      FIG. 7  is a perspective view illustrating another step of positioning the flexible circuit board unit on the fixing part of  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION 
       [0036]    Reference will now be made to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the 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.” In the following description, technical terms are used only for explaining exemplary embodiments, and not for purposes of limitation. Terms in the singular form may include the plural form unless specifically mentioned. The meaning of “comprises” and/or “comprising” specifies an element, a step, a process, an operation, and/or a device but does not exclude other elements, steps, processes, operations, and/or devices. It will be understood that although the terms such as “first” and “second” are used herein to describe various elements, these elements should not be limited by these terms. Terms are only used to distinguish one element from other elements. 
         [0037]      FIG. 1  is a perspective view illustrating a battery pack  100  according to an embodiment of the present invention.  FIG. 2  is an exploded perspective view illustrating the battery pack  100  illustrated in  FIG. 1 . 
         [0038]    Referring to  FIGS. 1 and 2 , the battery pack  100  may include a battery cell unit  110 , an outer cover  120 , a flexible circuit board unit  130 , a fixing part  140 , and a label  150 . 
         [0039]    The battery cell unit  110  may include a unit cell  111  and a protective circuit module  112 . The unit cell  111  may include a can having an accommodation space, an electrode assembly inserted into the accommodation space of the can, and a cap plate positioned on an upper side of the can. The electrode assembly may be a jelly-roll secondary battery electrode assembly. The can, the electrode assembly, and the cap plate may be identical or similar to those of conventional secondary batteries and should be apparent to those of ordinary skill in the art, and thus, detailed descriptions thereof will not be provided. 
         [0040]    In one embodiment, the protective circuit module  112  may be positioned on an upper surface of the unit cell  111  and may be electrically connected to the unit cell  111  so as to control the charging and discharging operations of the unit cell  111  and prevent (or reduce) overheating and explosion of the unit cell  111  that may be caused by overcharging, overdischarging, or an overcurrent. 
         [0041]    The protective circuit module  112  may include a circuit board  112   a , protection devices  112   b  on the circuit board  112   a , connection members  112   c , and external terminals  112   d . The external terminals  112   d  may be connected to an external device to either supply electricity from the unit cell  111  to the external device or to receive electricity from the external device, and to transmit or receive signals for controlling the charging and/or discharging of the unit cell  111 . The protection devices  112   b  may be positioned between the unit cell  111  and the circuit board  112   a  and may form a circuit for controlling the charging and discharging of the unit cell  111 . 
         [0042]    The connection members  112   c  may be placed on both ends of the circuit board  112   a  to electrically connect the circuit board  112   a  and the cap plate. In one embodiment, the connection members  112   c  are arranged such that the circuit board  112   a  is spaced from the cap plate. 
         [0043]    In addition to the above-described elements, the protective circuit module  112  may further include a temperature device  112   e  that electrically connects the unit cell  111  and the circuit board  112   a . In one embodiment, if the temperature of the unit cell  111  increases, the temperature device  112   e  may sever the connection between the unit cell  111  and the circuit board  112   a . The temperature device  112   e  may be identical or similar to those used in conventional secondary batteries and should be apparent to those of ordinary skill in the art, and thus, a detailed description thereof will not be provided. 
         [0044]    The outer cover  120  may be positioned on top of the protective circuit module  112 . In one embodiment, the outer cover  120  may entirely cover the protective circuit module  112  to shield the protective circuit module  112  from the surrounding environment. 
         [0045]    The flexible circuit board unit  130  may connect the external terminals  112   d  of the protective circuit module  112  to an external device. In one embodiment, the flexible circuit board unit  130  may be partially bent and may extend outward from the side of the outer cover  120  so as to be bent around the edges of the outer cover  120  and laid across an upper surface of the outer cover  120 . 
         [0046]    The flexible circuit board unit  130  may include a contact part  131 , and the contact part  131  may be in contact with the external terminals  112   d  and may be fixed to the external terminals  112   d . In one embodiment, the contact part  131  and the external terminals  112   d  may be soldered together or fixed together using a resin. In one embodiment, in order to facilitate the connection of the contact party  131  with the external terminals  112   d , the contact part  131  may have a plate shape and may include separate terminals respectively corresponding to the external terminals  112   d.    
         [0047]    The flexible circuit board unit  130  may include a cable part  132  connected to the contact part  131 . The cable part  132  may include a plurality of flexible cables that allow a flow of current and signals therethrough. 
         [0048]    The flexible circuit board unit  130  may further include a connector part  133  connected to the end of the cable part  132 . The connector part  133  may correspond to a connection unit of the external device. Specifically, the connector part  133  may have a protruded or grooved shape corresponding to the shape of the connection unit of the external device, so as to be connected and fixed to the connection unit. 
         [0049]    The flexible circuit board unit  130  may include a reinforcement part  134  positioned on a rear side of the connector part  133 . The reinforcement part  134  may have a plate shape and may be attached to the portion of the connector part  133  that is connected to the cable part  132 . 
         [0050]    The fixing part  140  may be formed on the upper surface of the outer cover  120  and may form an angle with the upper surface of the outer cover  120 . In one embodiment, the fixing part  140  may protrude upward from the upper surface of the outer cover  120 . The fixing part  140  may be coupled to and may hold in place the flexible circuit board unit  130 , while at the same time allowing for the movement of the flexible circuit board unit  130 . 
         [0051]    The label  150  may be wrapped around the unit cell  111 . The label  150  may be formed of an insulation material, and a portion of the label  150  may extend to cover the edges of the protective circuit module  112 . Referring to  FIG. 3 , the outer cover  120  may include a recess  121  formed around an outer edge of the outer cover  120 , and a portion of the label  150  may be placed inside the recess  121 . Accordingly, the outer cover  120  and the label  150  may shield the battery cell unit  110  and the protective circuit module  112  from the surrounding environment. 
         [0052]    Hereinafter, the outer cover  120  and the fixing part  140  will be described with reference to the figures. 
         [0053]      FIG. 3  is a perspective view illustrating the outer cover  120  illustrated in  FIG. 2 .  FIG. 4  is an enlarged perspective view illustrating the fixing part  140  illustrated in  FIG. 3 .  FIG. 5  is a perspective view illustrating the protective circuit module  112  and the flexible circuit board unit  130  illustrated in  FIG. 2 .  FIG. 6  is a perspective view illustrating a step in positioning the flexible circuit board unit  130  on the fixing part  140  illustrated in  FIG. 3 .  FIG. 7  is a perspective view illustrating another step in positioning the flexible circuit board unit  130  on the fixing part  140  illustrated in  FIG. 3 . 
         [0054]    Referring to  FIGS. 3 to 7 , the outer cover  120  may have an accommodation space therein, and the protective circuit module  112  may be placed in the accommodation space of the outer cover  120 . The outer cover  120  may include a first welding hole  122  for welding a terminal of the protective circuit module  112  and a portion of the temperature device  112   e . Furthermore, coupling protrusions may be formed on a rear (bottom) surface of the outer cover  120  around the welding hole  122  for coupling with second welding holes of the circuit board  112   a . The coupling protrusions may protrude from the rear (bottom) surface of the outer cover  120  toward the circuit board  112   a.    
         [0055]    The outer cover  120  may include a pullout slot  123 , and a portion of the flexible circuit board unit  130  may extend outward from the outer cover  120  through the pullout slot  123 . In one embodiment, the pullout slot  123  may be formed in a lateral (longer) side of the outer cover  120 . The width of the pullout slot  123  may be equal or approximately equal to the width W of the cable part  132 , as illustrated in  FIG. 6 . 
         [0056]    A shield plate  160  may be positioned on the first welding hole  122  of the outer cover  120 . To accommodate the shield plate  160 , the outer cover  120  may include a shield plate recess  124 , and the shield plate  160  may be positioned in the shield plate recess  124 . The shield plate  160  may be formed of a material identical or similar to a material used to form the outer cover  120 , or a material different from the one used to form the outer cover  120 . In one embodiment, the shield plate  160  and the outer cover  120  may be coupled to each other by any suitable welding or bonding method. 
         [0057]    The outer cover  120  may include stopper protrusions  125  protruding inward toward the middle of the outer cover  120 . The stopper protrusions  125  of the outer cover  120  may be brought into contact with or hooked on the protective circuit module  112  and/or the battery cell unit  110 , thus fixing the outer cover  120  to the protective circuit module  112  and/or the battery cell unit  110 . 
         [0058]    The fixing part  140  may be formed on the upper surface of the outer cover  120  and may form an angle with the upper surface of the outer cover  120 . In one embodiment, the fixing part  140  may protrude outward from the upper surface of the outer cover  120  and may form a right angle with the upper surface of the outer cover  120 . However the angle between the fixing part  140  and the upper surface of the outer cover  120  is not limited to a right angle. Hereinafter, solely for convenience of description, it will be assumed that the angle between the fixing part  140  and the upper surface of the outer cover  120  is a right angle. 
         [0059]    Referring to  FIGS. 3 and 4 , the fixing part  140  may include a guide portion  141  connected to the upper surface of the outer cover  120 . In one embodiment, the guide portion  141  may guide the flexible circuit board unit  130  to be positioned upright relative to the upper surface of the outer cover  120 . The fixing part  140  may further include a lateral portion  142  bent from the guide portion  141  to cover (surround) the side edges of the flexible circuit board unit  130 . 
         [0060]    The fixing part  140  may also include a support portion  143  bent from the lateral portion  142 . The support portion  143  may be spaced from the guide portion  141 . 
         [0061]    The lateral portion  142  may include a first lateral portion  142   a  bent from one side of the guide portion  141 , and a second lateral portion  142   b  bent from the other side of the guide portion  141  and facing the first lateral portion  142   a.    
         [0062]    A distance S 1  between the first and second lateral portions  142   a  and  142   b  may be equal or approximately equal to the width of the flexible circuit board unit  130 . Specifically, the distance S 1  between the first and second lateral portions  142   a  and  142   b  may be equal or approximately equal to the width W of the cable part  132 . 
         [0063]    As described above, the support portion  143  formed on the lateral portion  142  may face the guide portion  141 , and a space may be formed between the support portion  143  and the guide portion  141 . In one embodiment, a distance S 2  between the support portion  143  and the guide portion  141  may be different from the thickness of a portion of the flexible circuit board unit  130  inserted between the guide portion  141  and the support portion  143 . For example, the distance S 2  between the support portion  143  and the guide portion  141  may be greater than the thickness of the cable part  132  of the flexible circuit board unit  130 . 
         [0064]    In one embodiment, the fixing part  140  may include a plurality of support portions  143 . In one embodiment, the plurality of support portions  143  may include a first support portion  143   a  and a second support portion  143   b  facing the first support portion  143   a . The first support portion  143   a  may be bent from the first lateral portion  142   a  and may protrude inward toward the middle of the guide portion  141 , and the second support portion  143   b  may be bent from the second lateral portion  142   b  and may protrude inward toward the middle of the guide portion  141 . 
         [0065]    A distance between the first and second support portions  143   a  and  143   b  may be smaller than the width of the flexible circuit board unit  130 . For example, the shortest distance between the first and second support portions  143   a  and  143   b  may be smaller than the width W of the cable part  132  of the flexible circuit board unit  130 . 
         [0066]    At least one of the first and second support portions  143   a  and  143   b  may be spaced by a distance S 3  from the upper surface of the outer cover  120 . The distance S 3  from the upper surface of the outer cover  120  to the at least one of the first and second support portions  143   a  and  143   b  may be different from the thickness of the flexible circuit board unit  130 . For example, the distance S 3  from the upper surface of the outer cover  120  to the at least one of the first and second support portions  143   a  and  143   b  may be greater than the thickness of the cable part  132  of the flexible circuit board unit  130 . 
         [0067]    The battery pack  100  may be manufactured as follows. First, the unit cell  111  and the protective circuit module  112  may be manufactured and coupled to each other. At this time, the contact part  131  of the flexible circuit board unit  130  may be positioned on the external terminals  112   d  of the protective circuit module  112 . 
         [0068]    Then, the unit cell  111  may be covered with the label  150 , and the outer cover  120  may be attached to the unit cell  111 . At this time, the stopper protrusions  125  of the outer cover  120  may be brought into contact with or hooked on the circuit board  112   a , thus fixing the outer cover  120  to the circuit module  112  and the unit cell  111 . Part of the label  150  may be placed in the recess  121  formed on the outer edges of the outer cover  120 . Accordingly, the label  150  may shield the unit cell  111  and the protective circuit module  112  from the surrounding environment. 
         [0069]    The cable part  132  may be pulled out from inside the outer cover  120  through the pullout slot  123 . In order to shield the inside of the outer cover  120  exposed after the cable part  132  is pulled out, part of the label  150  may extend toward the outer cover  120  and may be spaced from a portion of the outer cover  120  in which the pullout slot  123  is formed. 
         [0070]    Thereafter, the cable part  132  may be bent around the edge of the outer cover  120  where the pullout slot  123  is formed and may be laid across the upper surface of the outer cover  120 . 
         [0071]    Thereafter, the cable part  132  may be inserted between the first and second lateral portions  142   a  and  142   b . Since the distance S 1  between the first and second lateral portions  142   a  and  142   b  is equal or approximately equal to the width W of the cable part  132 , the cable part  132  may be easily inserted between the first and second lateral portions  142   a  and  142   b.    
         [0072]    Herein, the cable part  132  may be bent again, along the side of the guide portion  141 , so as to form a right angle with the upper surface of the outer cover  120 . 
         [0073]    The bent cable part  132  may be positioned between the guide portion  141  and the first and second support portions  143   a  and  143   b . The distance S 2  from the guide portion  141  to the first and second support portions  143   a  and  143   b  may be greater than the thickness of the cable part  132 . Accordingly, the cable part  132  may move between the guide portion  141  and the first and second support portions  143   a  and  143   b.    
         [0074]    After the flexible circuit board unit  130  is positioned as described above, the connector part  133  may be positioned away from the upper surface of the outer cover  120 . 
         [0075]    Then, the battery pack  100  may be attached to an external device such as a cellular phone or a laptop computer. In this case, the connector part  133  may be connected to a connection unit of the external device to supply power to the external device. 
         [0076]    When the battery pack  100  is connected to an external device as described above, an impact on the external device or movement of the battery pack  100  may cause the cable part  132  to be bent or moved. However, since the fixing part  140  holds the cable part  132  in place, the fixing part  140  may prevent (or reduce) bending or movement of the cable part  132 , thus preventing (or reducing) damage to the cable part  132  or the possibility of the cable part  132  being disconnected from the external device. 
         [0077]    Furthermore, the fixing part  140  allows for movement of the cable part  132 . Accordingly, when the battery pack  100  is moved or the external device is hit (or otherwise impacted), the damage to the cable part  132  from the fixing part  140  itself may be prevented (or reduced). 
         [0078]    In other words, the flexible circuit board unit  130  may be securely fixed, and the separation of the flexible circuit board unit  130  may be prevented (or reduced), while still allowing movement of the flexible circuit board unit  130  within a predetermined range inside the fixing part  140 . 
         [0079]    Accordingly, the damage to the flexible circuit board unit  130  of the battery pack  100  can be prevented (or reduced), and a stable connection between the unit cell  111  and the external device may be established. 
         [0080]    In one embodiment, the structure of the fixing part  140  holding the flexible circuit board unit  130  may allow for the flexible circuit board unit  130  of the battery pack  100  to be easily assembled. 
         [0081]    It should be understood that the exemplary embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. 
         [0082]    While one or more embodiments of the present invention have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims and equivalents thereof.