Abstract:
A rechargeable battery that can improve heat dissipating characteristics is provided. The rechargeable battery comprises: an electrode group including a positive electrode; an electrode group that has at least one terminal; a case that defines a recess that receives the electrode group wherein the case includes an opening that provides access to the recess; a film cover that extends over the opening so as to secure the electrode group within the recess of the case; and a heat dissipating member positioned on the case so as extend outward from the case to dissipate heat from the recess containing the electrode group. 
     A battery assembly comprises: a plurality of battery modules wherein each of the battery modules include an electrode group positioned within a recess in a case wherein the case defines an opening that is covered by a film cover and wherein the case includes at least one first heat dissipating member that extends outward from the case; wherein the plurality of battery modules are stacked and coupled together so that the film covers are protected from external impacts.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of Provisional Patent Application No. 61/234,893 filed on Aug. 18, 2009 in the U.S. Patent and Trademark Office, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    The described technology relates generally to a rechargeable battery and a battery module. More particularly, the described technology relates generally to a rechargeable battery and a battery module having a case with an improved structure. 
         [0004]    2. Description of the Related Technology 
         [0005]    A rechargeable battery can be recharged and discharged, in contrast to a primary battery that cannot be recharged. A low capacity rechargeable battery is generally used as a power source for a small portable electronic device, such as a mobile phone, a laptop computer, and a camcorder, etc., and a large capacity rechargeable battery is generally used as a power source for driving a motor such as for a hybrid vehicle. 
         [0006]    A large capacity high power rechargeable battery with high energy density using a non-aqueous electrolyte has been developed, and the rechargeable battery is generally formed with a large capacity high power rechargeable battery module by coupling a plurality of rechargeable batteries in series or in parallel in order to use it to drive a device, for example, a motor such as an electric vehicle requiring a large amount of electric power. 
         [0007]    Further, a high power rechargeable battery is generally formed with a plurality of rechargeable batteries that are coupled in series or in parallel, and the rechargeable battery may be formed in a cylindrical shape or a square shape. 
         [0008]    A conventional rechargeable battery includes an electrode group in which a positive electrode and a negative electrode are positioned with a separator interposed therebetween, a metal can having a space that houses the electrode group, a cap plate that closes and seals the metal can and in which a terminal hole that has a terminal inserted therein is formed, and a terminal that is electrically connected to the electrode group and that is inserted into the terminal hole to protrude to the outside of a case. 
         [0009]    A lithium ion battery among existing rechargeable batteries is used as a small mobile terminal battery, uses a small metal can or a film type pouch sheath material, and has a secure sealing structure through welding or fusing in order to isolate the outside from the inside of the battery. 
         [0010]    However, a pouch type battery is weak with respect to external impact and cannot easily discharge heat. Further, because the pouch type battery has no structure that fixes its external shape, it is difficult to manufacture the pouch type batteries with a battery module by stacking. 
         [0011]    A metal can type battery has high strength, but has a heavy weight and has a difficulty in discharging internal heat to the outside. 
         [0012]    The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
       SUMMARY 
       [0013]    The described technology has been made in an effort to provide a rechargeable battery and a battery module improving output per unit weight and improving heat dissipating characteristics. 
         [0014]    An embodiment of the present invention provides a rechargeable battery including: an electrode group including positive electrodes, negative electrodes, and separators that are disposed between the positive electrodes and the negative electrodes; a mounting recess that houses the electrode group; a case that has a heat dissipating flange formed at an upper end of the mounting recess; and a film cover that is installed at the upper end of the mounting recess to seal the mounting recess. 
         [0015]    A bent heat dissipating plate may be formed in the heat dissipating flange, and a terminal recess in which a terminal that is electrically connected to the electrode group is inserted may be formed in the heat dissipating flange. 
         [0016]    An insulation layer that encloses a circumference of the terminal may be formed in the terminal, the insulation layer may be inserted into the terminal recess, and a sealing layer to which the film cover is attached may be formed in the heat dissipating flange. 
         [0017]    The sealing layer may be patterned in a check pattern or a stripe pattern, a positive terminal may be electrically connected to a positive electrode of the electrode group, a negative terminal may be electrically connected to a negative electrode of the electrode group, and the positive terminal or the negative terminal may be attached to an inner surface of the mounting recess. 
         [0018]    An insulation film may be coated on an inner surface of the case, and the film cover may include a metal foil and a polymer layer that is disposed at both surfaces of the metal foil. 
         [0019]    The case may include a bottom heat dissipating portion that is formed in the bottom of the mounting recess, and a cooling flow path that circulates a coolant may be formed within the bottom heat dissipating portion. A protruding heat dissipating fin may be formed in an external wall surface of the mounting recess, and the protruding heat dissipating fin may be formed in the heat dissipating flange. 
         [0020]    Another embodiment of the present invention provides a battery module including: an electrode group including positive electrodes, negative electrodes, and separators that are disposed between the positive electrodes and the negative electrodes; a mounting recess that houses the electrode group, a case that has a heat dissipating flange that is formed at an upper end of the mounting recess; a plurality of rechargeable batteries including a film cover that is installed at an upper end of the mounting recess to seal the mounting recess; and a fixing member that puts pressure on the rechargeable batteries. 
         [0021]    A hollow spacer that receives a fixing member may be installed between heat dissipating flanges of neighboring rechargeable batteries, and the rechargeable battery may be disposed to contact the film cover with a rechargeable battery of one side and to contact the bottom of the mounting recess with a rechargeable battery of the other side. 
         [0022]    The rechargeable battery may include a positive terminal that is electrically connected to a positive electrode of the electrode group and a negative terminal that is electrically connected to a negative terminal of the electrode group, the positive terminal may be opposite to a positive terminal of a neighboring rechargeable battery, the negative terminal may be opposite to a negative terminal of a neighboring rechargeable battery, the positive terminal may be welded to a positive terminal of a neighboring rechargeable battery, and the negative terminal may be welded to a negative terminal of a neighboring rechargeable battery. 
         [0023]    The rechargeable battery may include a positive terminal that is electrically connected to a positive electrode of the electrode assembly and a negative terminal that is electrically connected to a negative electrode of the electrode assembly, and at one side thereof, the positive terminal and a negative terminal of a neighboring rechargeable battery may be bonded by welding, and at the other side thereof, the negative terminal and a positive terminal of a neighboring rechargeable battery may be bonded by welding. 
         [0024]    The case may include a bottom heat dissipating portion that is formed in the bottom of the mounting recess, and a cooling flow path that circulates a coolant may be formed within the bottom heat dissipating portion. 
         [0025]    According to an embodiment of the present invention, heat dissipating characteristics of a rechargeable battery are improved and output per unit weight thereof is improved. Further, a battery module is easily fastened and assembled. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]      FIG. 1  is a perspective view illustrating a rechargeable battery according to a first embodiment of the present invention. 
           [0027]      FIG. 2  is a cross-sectional view of the rechargeable battery taken along line II-II of  FIG. 1 . 
           [0028]      FIG. 3A  is a top plan view illustrating a case according to a first embodiment of the present invention, and  FIG. 3B  is a top plan view illustrating a modified example of a case according to a first embodiment of the present invention. 
           [0029]      FIG. 4  is a cross-sectional view illustrating a battery module according to a first embodiment of the present invention. 
           [0030]      FIG. 5  is an exploded perspective view illustrating a rechargeable battery according to a second embodiment of the present invention. 
           [0031]      FIG. 6  is a side view illustrating a battery module according to a second embodiment of the present invention. 
           [0032]      FIG. 7  is a side view illustrating a battery module according to a third embodiment of the present invention. 
           [0033]      FIG. 8  is an exploded perspective view illustrating a rechargeable battery according to a fourth embodiment of the present invention. 
           [0034]      FIG. 9  is a perspective view illustrating a rechargeable battery according to a fifth embodiment of the present invention. 
           [0035]      FIG. 10  is a rear view illustrating a rechargeable battery according to a fifth embodiment of the present invention. 
           [0036]      FIG. 11  is a cross-sectional view illustrating a case and a film cover of a rechargeable battery according to a sixth embodiment of the present invention. 
           [0037]      FIG. 12  is a cross-sectional view illustrating a case and a film cover of a rechargeable battery according to a seventh embodiment of the present invention. 
           [0038]      FIG. 13  is a perspective view illustrating a rechargeable battery according to the eighth embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0039]    Embodiments of the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the specification and drawings, like reference numerals designate like elements. 
         [0040]      FIG. 1  is a perspective view illustrating a rechargeable battery according to a first embodiment of the present invention, and  FIG. 2  is a cross-sectional view of the rechargeable battery taken along line II-II of  FIG. 1 . 
         [0041]    Referring to  FIGS. 1 and 2 , a rechargeable battery  100  according to the illustrated embodiment includes an electrode assembly  10  in which separators  13  may be interposed between positive electrodes  11  and negative electrodes  12 , a case  20  that houses the electrode assembly  10 , a positive electrode terminal  31  and a negative electrode terminal  32  that are electrically connected to the electrode assembly  10 , and a film cover  40  that seals the case  20 . As an example of the rechargeable battery  100  according to the illustrated embodiment, a lithium-ion rechargeable battery is described. 
         [0042]    The positive electrode  11  may be formed in a structure in which a positive active material is coated on a positive current collector, and the negative electrode  12  formed in a structure in which a negative active material is coated on a negative current collector. The electrode assembly  10  may be formed in a structure in which a plurality of positive electrodes  11  and negative electrodes  12  are alternately stacked with the separators  13  interposed therebetween. 
         [0043]    However, embodiments of the present invention are not limited thereto, and the electrode assembly  10  may be formed in a structure of interposing the separators  13  between the positive electrodes  11  and the negative electrodes  12  of a belt shape and spiral-winding them. 
         [0044]    In the stacked electrode assembly  10 , a positive uncoated region and a negative uncoated region may be positioned at one side end thereof, the positive electrode terminal  31  may be attached to the positive uncoated region by welding, and the negative electrode terminal  32  may be attached to the negative uncoated region by welding. In the positive electrode terminal  31  and the negative electrode terminal  32 , an insulation layer  36  for insulation from the case  20  may be formed to enclose a circumference of the terminals  31  and  32 . 
         [0045]    The case  20  can include a mounting recess  21  that houses the electrode assembly  10 , and a heat dissipating flange  25  that is extended to the outside from an upper end of the mounting recess  21 . The mounting recess  21  may have an approximately quadrangular shape, and be disposed at the center of the case  20 . The case  20  may be formed with a plate shape, and the mounting recess  21  may be formed by bending a plate-shaped case. The case may include aluminum, stainless steel, nickel, or an alloy thereof. 
         [0046]    The heat dissipating flange  25  may be formed along a circumference of the mounting recess  21 , and a fastening hole  25   b  may be formed at the corner of the heat dissipating flange  25 . A terminal recess  26  in which the terminals  31  and  32  are inserted may be formed in the heat dissipating flange  25 , and the terminal recess  26  may be formed from an external end portion of the heat dissipating flange  25  to the mounting recess  21 . The insulation layer  36  may be inserted into the terminal recess  26  to seal between the case  20  and the film cover  40 . 
         [0047]    Further, in the heat dissipating flange  25 , a sealing portion  25   a  that attaches the film cover  40  may be formed in a portion contacting with the mounting recess  21 . 
         [0048]    As shown in  FIG. 3A , in the sealing portion  25   a , an adhesive  27  may be patterned in a check form and coated. Further, as shown in  FIG. 3B , in a sealing portion  28   a  that is formed in a heat dissipating flange  28  of a case  20 ′, the adhesive  29  may be patterned in a stripe form. When the sealing portions  25   a  and  28   a  are patterned in a check form or a stripe form, the film cover  40  more closely contacts with the sealing portions  25   a  and  28   a  to stably seal the mounting recess  21 . 
         [0049]    The film cover  40  may be bonded to the sealing portion  25   a , be formed in an approximately quadrangular shape, and may cover entirely an opening of the mounting recess  21 . Accordingly, the mounting recess  21  entirely sealed by the film cover  40 . The film cover  40  may be made of a polymer, or be formed in a structure in which a polymer is coated on both surfaces of a metal foil. 
         [0050]    A bent heat dissipating plate  23  entirely formed at one end of the heat dissipating flange  25 . The heat dissipating plate  23  may be bent toward a bottom direction of the mounting recess  21 , and be formed at a position that is separated from the mounting recess  21 . 
         [0051]    Accordingly, by discharging a heat through the heat dissipating plate  23 , the case  20  can be efficiently cooled. The heat dissipating plate  23  can be formed integrally with the heat dissipating flange  25 , and heat that is generated within the case  20  can be rapidly discharged through the heat dissipating flange  25  and the heat dissipating plate  23 . 
         [0052]      FIG. 4  is a cross-sectional view illustrating a battery module according to a first embodiment of the present invention. 
         [0053]    Referring to  FIG. 4 , a battery module  500  according to the first illustrated embodiment includes a plurality of stacked rechargeable batteries  100 , end plates  46  and  47  that are installed at the outermost sides of the rechargeable batteries  100 , and a fixing member  42  that penetrates through and is fastened to the end plates  46  and  47  and the case  20  of the rechargeable batteries  100 . 
         [0054]    The rechargeable batteries  100  may be stacked so that the bottom of the mounting recess  21  contacts with a heat dissipating flange  25  of a neighboring rechargeable battery  100 , and the bottom of a neighboring rechargeable battery  100  is positioned on a film cover  40 . Accordingly, the film cover  40  can be safely protected from an external impact. Further, walls of the mounting recess  21  may be arranged in a line in order to support a load that is transferred through a neighboring case  20 . 
         [0055]    A fixing member  42  may be inserted into a fastening hole  25   b  that is formed in the heat dissipating flange  25 , and the fixing member  42  may penetrate through and be fastened to the end plates  46  and  47  and the heat dissipating flange  25 . 
         [0056]    The fixing member  42  may include a connecting bar  42   b  in which a head portion  42   a  is formed at one side thereof and a nut  42   c  that is fastened to the connecting bar  42   b . The fixing member  42  may be integrally fixed by putting pressure on the cases  20 . 
         [0057]    A spacer  45  may be installed between the heat dissipating flanges  25  of neighboring rechargeable batteries  100 , and formed with a hollow shape in order to insert the fixing member  42  therein. 
         [0058]    The end plates  46  and  47  may be installed in an upper part and a lower part of the battery module  100 , respectively, the end plate  47  that is installed at one side thereof can closely contacts the bottom of the case  20 , and the end plate  46  that is installed at the other side thereof can cover the film cover  40 . 
         [0059]    According to the present illustrated embodiment, by stacking the cases  20 , the battery module  500  can be easily manufactured, and when an error occurs in some rechargeable battery  100 , the rechargeable battery  100  can be easily replaced and repaired. Further, heat can be easily discharged through the heat dissipating flange  25  that is formed in the cases  20 . 
         [0060]      FIG. 5  is an exploded perspective view illustrating a rechargeable battery according to a second embodiment of the present invention. 
         [0061]    Referring to  FIG. 5 , a rechargeable battery  110  according to the present illustrated embodiment includes an electrode assembly  51  in which separators are interposed between positive electrodes  51   a  and negative electrodes  51   b , a case  50  that houses the electrode assembly  51 , a positive electrode terminal  61  and a negative electrode terminal  62  that are electrically connected to the electrode assembly  51 , and a film cover  40  that seals the case  50 . 
         [0062]    The electrode assembly  51  may be formed by interposing a separator between the positive electrode  51   a  and the negative electrode  51   b  of a belt shape, and spiral-winding them. In the spiral-wound electrode assembly  51 , a positive uncoated region may be formed at one side end thereof and a negative uncoated region formed at the other side end thereof. In the electrode assembly  51 , the positive electrode terminal  61  may be attached to the positive uncoated region by welding, and the negative electrode terminal  62  attached to the negative uncoated region by welding. Accordingly, the positive electrode terminal  61  and the negative electrode terminal  62  can protrude in opposite directions. 
         [0063]    In the positive electrode terminal  61  and the negative electrode terminal  62 , insulation layers  64  and  65  for insulation from the case  50  may be formed to enclose circumferences of the terminals  61  and  62 . 
         [0064]    The case  50  can include a mounting recess  52  that houses the electrode assembly  51 , and a heat dissipating flange  55  that is extended to the outside from an upper end of the mounting assembly  52 . The mounting assembly  52  may have an approximately quadrangular shape and be disposed at the center of the case  50 . 
         [0065]    The heat dissipating flange  55  may be formed along a circumference of the mounting assembly  52 , and a fastening hole  55   b  formed at the corner of the heat dissipating flange  55 . A terminal recess  56  in which the terminals  61  and  62  are inserted may be formed in the heat dissipating flange  55 , and the terminal recess  56  formed from an external end portion of the heat dissipating flange  55  to the mounting recess  52 . An insulation layer  65  may be inserted into the terminal recess  56  to seal between the case  50  and the film cover  40 . 
         [0066]    Further, a sealing portion  55   a  may be formed in the heat dissipating flange  55  so that the film cover  40  may be attached to a portion contacting the mounting recess  52 . A bent heat dissipating plate  53  may be formed at one end of the heat dissipating flange  55 . The heat dissipating plate  53  may be bent in a bottom direction of the mounting recess  52  from the heat dissipating flange  55 , and formed at a position that is separated from the mounting recess  52 . 
         [0067]    A coolant may be supplied to a space between the heat dissipating plate  53  and the mounting recess  52  to efficiently cool the case  50 . The heat dissipating plate  53  may be integrally formed with the heat dissipating flange  55 , and heat that is generated within the case  50  can be rapidly discharged through the heat dissipating flange  55  and the heat dissipating plate  53 . 
         [0068]      FIG. 6  is a side view illustrating a battery module  600  according to a second embodiment of the present invention. 
         [0069]    Referring to  FIG. 6 , a battery module  600  according to the present illustrated embodiment includes a plurality of rechargeable batteries  110  and connection members  65  and  67  that electrically connect the rechargeable batteries  110 . 
         [0070]    One rechargeable battery  110  may be disposed to contact via a film cover  40  with a rechargeable battery  110  of one side and to contact in the bottom of a mounting recess  52  with a rechargeable battery  110  of the other side. Accordingly, because the film cover  40  is disposed between the heat dissipating flanges  55 , the film cover  40  can be prevented from being damaged by an external impact. In this case, a positive electrode terminal  61  is opposite to a positive electrode terminal  61  of a neighboring rechargeable battery  110 , and a negative electrode terminal  62  is opposite to a negative electrode terminal  62  of a neighboring rechargeable battery  110 . 
         [0071]    The positive electrode terminal  61  may be welded to the negative electrode terminal  62  of a neighboring rechargeable battery  110  and the negative electrode terminal  62  may be welded to the negative electrode terminal  62  of a neighboring rechargeable battery  110 , and thus two rechargeable batteries  110  may be coupled in parallel. The connection members  65  and  67  can electrically connect two rechargeable batteries  110 , and in the present illustrated embodiment, the rechargeable batteries  110  are coupled in parallel. According to the present illustrated embodiment, by electrically connecting a plurality of small rechargeable batteries  110 , a large capacity battery module can be formed and structural stability of the battery module and an output to weight ratio thereof can be improved. 
         [0072]    However, embodiments of the present invention are not limited thereto, and the connection members  65  and  67  may connect six rechargeable batteries  110  with a 2P3S structure by coupling two rechargeable batteries  110  in series. 
         [0073]      FIG. 7  is a side view illustrating a battery module  700  according to a third embodiment of the present invention. 
         [0074]    Referring to  FIG. 7 , a rechargeable battery  110  according to the present illustrated embodiment is formed in the same structure as that of the rechargeable battery  110  according to the second described embodiment, and therefore a detailed description thereof will not be presented. 
         [0075]    One rechargeable battery  110  may be disposed to contact via a film cover  40  with a rechargeable battery  110  of one side and to contact in the bottom of a mounting recess  52  with a rechargeable battery  110  of the other side. In this case, a positive electrode terminal  61  is opposite to a negative electrode terminal  62  of a neighboring rechargeable battery  110 , and a negative electrode terminal  62  is opposite to a positive electrode terminal  61  of a neighboring rechargeable battery  110 . 
         [0076]    At one side, adjacent positive and negative electrode terminals  61  and  62  may be bonded by welding, and at the other side, distant negative and positive electrode terminals  62  and  61  may be bonded by welding. Accordingly, the rechargeable batteries  110  can be coupled in series without interposing a separate member. 
         [0077]      FIG. 8  is an exploded perspective view illustrating a rechargeable battery according to a fourth embodiment of the present invention. 
         [0078]    Referring to  FIG. 8 , a rechargeable battery  120  according to the present illustrated embodiment includes an electrode assembly  51  in which a separator is interposed between a positive electrode  51   a  and a negative electrode  51   b , a case  70  that houses the electrode assembly  51 , a positive electrode terminal  76  and negative electrode terminal  78  that are electrically connected to the electrode assembly  51 , and a film cover  40  that seals the case  70 . 
         [0079]    The electrode assembly  51  according to the present embodiment may be formed in the same structure as that of the electrode assembly according to the second embodiment, and therefore a detailed description thereof will not be presented. 
         [0080]    The case  70  can include a mounting recess  71  that houses the electrode assembly  51 , and a heat dissipating flange  75  that is extended to the outside from an upper end of the mounting recess  71 . The mounting recess  71  may have an approximately quadrangular shape, and is disposed at the center of the case  70 . 
         [0081]    In the electrode assembly  51 , the positive electrode terminal  76  may be attached to the positive electrode  51   a  thereof by welding, and the negative electrode terminal  78  may be attached to the negative electrode  51   b  thereof by welding. Accordingly, the positive electrode terminal  76  and the negative electrode terminal  78  can protrude in opposite directions. 
         [0082]    In the positive electrode terminal  76 , an insulation layer  79  for insulation from the case  70  may be formed to enclose a circumference of the positive electrode terminal  76 . The negative electrode terminal  78  may be bent toward the bottom of the mounting recess  71  and attached to an inner wall surface of the mounting recess  71  by welding. Accordingly, the case  70  can have negative polarity. Therefore, the rechargeable batteries  120  can be stacked, and the rechargeable batteries  120  can be easily coupled in series by simply attaching the positive electrode terminal  76  to a case  70  of a neighboring rechargeable battery  120  by welding. 
         [0083]    The heat dissipating flange  75  may be formed along a circumference of the mounting recess  71 , and a fastening hole  75   b  may be formed at the corner of the heat dissipating flange  75 . A terminal recess  74  in which the positive electrode terminal  76  may be inserted may be formed in the heat dissipating flange  75 , and the insulation layer  79  may be inserted into the terminal recess  74  to seal between the case  70  and the film cover  40 . 
         [0084]    Further, a sealing portion  75   a  may be formed in the heat dissipating flange  75  so that the film cover  40  may be attached to a portion contacting the mounting recess  71 . A bent heat dissipating plate  73  may be formed at one end of the heat dissipating flange  75 . The heat dissipating plate  73  may be bent in a bottom direction of the mounting recess  71  from the heat dissipating flange  75 , and formed at a position that is separated from the mounting recess  71 . 
         [0085]      FIG. 9  is a perspective view illustrating a rechargeable battery according to a fifth embodiment of the present invention, and  FIG. 10  is a rear view illustrating a rechargeable battery according to the fifth illustrated embodiment of the present invention. 
         [0086]    Referring to  FIGS. 9 and 10 , a rechargeable battery  130  according to the present illustrated embodiment includes a case  85 , an electrode assembly  88  that is inserted into the case  85 , a positive electrode terminal  81  and negative electrode terminal  82  that are electrically connected to the electrode assembly  88  and that protrude to the outside of the case  85 , and a film cover  84  that seals the case  85 . 
         [0087]    The case  85  can include a mounting recess  86  that houses the electrode assembly  88 , and a heat dissipating flange  87  that is extended to the outside from an upper end of the mounting recess  86 . The mounting recess  86  can have an approximately quadrangular shape, and disposed at the center of the case  85 . 
         [0088]    The heat dissipating flange  87  may be formed along the circumference of the mounting recess  86 , and a bent heat dissipating plate  89  may be formed at one side end of the heat dissipating flange  87 . 
         [0089]    The positive electrode terminal  81  may be electrically connected to a positive electrode  88   a  of the electrode assembly  88  to penetrate through a wall surface of the mounting recess  86  and to protrude to the outside, and the negative electrode terminal  82  may be electrically connected to a negative electrode  88   b  of the electrode assembly  88  to penetrate through a wall surface of the mounting recess  86  and to protrude to the outside. In this case, a gasket  83  for insulation may be installed between the case  85  and the terminals  81  and  82 . 
         [0090]      FIG. 11  is a cross-sectional view illustrating a case and a film cover of a rechargeable battery according to a sixth embodiment of the present invention. 
         [0091]    Referring to  FIG. 11 , a case  220  according to the present illustrated embodiment includes a mounting recess  221  that houses an electrode assembly and a heat dissipating flange  250  that is extended to the outside from an upper end of the mounting recess  221 . The mounting recess  221  may have an approximately quadrangular shape and be disposed at the center of the case  220 . 
         [0092]    The heat dissipating flange  250  may be formed along a circumference of the mounting recess  221 , and a bent heat dissipating plate  223  may be formed at one side end of the heat dissipating flange  250 . 
         [0093]    An insulation film  230  for insulation may be coated on an inner surface of the case  220 . The insulation film  230  may be made of a polymer, as an example. Further, in the heat dissipating flange  250 , an adhesive layer  260  may be formed in an upper surface of the heat dissipating flange  250  to which a film cover may be attached, and thus the film cover  240  can be stably attached to the heat dissipating flange  250 . 
         [0094]    The film cover  240  can include a metal foil  241  that is disposed at the center thereof, and polymer layers  242  and  243  that are disposed at both surfaces of the metal foil  241 . Accordingly, because the polymer layers  242  and  243  and the adhesive layer  260  are bonded by thermo-compression, the film cover  240  can be stably fixed to the case  220 , and the metal foil  241  can provide predetermined strength to the film cover  240 . 
         [0095]      FIG. 12  is a cross-sectional view illustrating a case and a film cover of a rechargeable battery according to a seventh embodiment of the present invention. 
         [0096]    Referring to  FIG. 12 , a case  320  according to the present illustrated embodiment includes a mounting recess  321  that houses an electrode group, and a heat dissipating flange  325  that is extended to the outside from an upper end of the mounting recess  321 . The mounting recess  321  may have approximately a quadrangular shape, and disposed at the center of the case  320 . A film cover  340  that covers the mounting recess  321  may be installed in the case  320 . 
         [0097]    The heat dissipating flange  325  may be formed along a circumference of the mounting recess  321 , and a bent heat dissipating plate  327  may be formed at one side end of the heat dissipating flange  325 . A bottom cooling part  324  may be formed in the bottom of the mounting recess  321 , and a cooling flow path  324   a  in which a coolant can move may be formed within the bottom cooling part  324 . Further, a heat dissipating fin  328  protruded in parallel to the heat dissipating flange  325  may be formed in an external wall surface of the mounting recess  321 . 
         [0098]    A heat dissipating fin  329  protruded in parallel to the heat dissipating plate  327  may be formed in the heat dissipating flange  325  in which the heat dissipating plate  327  may be formed. 
         [0099]    According to the present illustrated embodiment, the heat dissipating fins  328  and  329  and the cooling flow path  324   a  may be formed in the case  320  to easily discharge heat generated within the case  320 . 
         [0100]      FIG. 13  is a perspective view illustrating a rechargeable battery according to the eighth embodiment of the present invention. 
         [0101]    Referring to  FIG. 13 , a case  201  of a rechargeable battery according to the present illustrated embodiment does not include a heat dissipating plate (reference numeral  23  of  FIG. 1 ). As such, the case  201  has a simple structure, thereby reducing the time and the cost for manufacturing the case  201 . 
         [0102]    In  FIG. 13 , the elements other than the case are the same as those of the first embodiment shown in  FIG. 1 . The present invention, however, is not limited thereto. Thus, the case not having the heat dissipating plate can be applied to the second to seventh embodiments. 
         [0103]    While this disclosure has been described in connection with what is presently considered to be practical 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.