CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to and the benefit of U.S. Provisional Application No. 61/287,663, filed on Dec. 17, 2009, the entire content of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    The present invention relates to a rechargeable battery, and more particularly, to a separator finishing structure of a laminate type of electrode assembly. 
         [0004]    2. Description of the Related Technology 
         [0005]    A rechargeable battery differs from a primary battery in that it can be repeatedly charged and discharged, while the latter can only irreversibly convert chemical energy to electrical energy. A low-capacity rechargeable battery is typically used as a power supply for small electronic devices, such as cellular phones, notebook computers, and camcorders, while a high-capacity rechargeable battery is typically used as a power supply for driving motors in hybrid vehicles and the like. 
         [0006]    A rechargeable battery generally includes an electrode assembly with a positive electrode plate, a separator, and a negative electrode plate, and a case receiving the electrode assembly. The case is formed with a cylindrical or prismatic metal can, or with a laminate sheet having a resin sheet layer and a metal sheet layer. The electrode assembly may be formed as a spiral-wound type or a laminate type depending upon the shape of the case. 
         [0007]    With the laminate type of electrode assembly in which several sheets of positive electrode plates, separators, and negative electrode plates are laminated, the edges of the separators protruded to the outside of the positive and negative electrode plates are typically tightly adhered to each other, and wrapped by an adhesive tape, thereby holding the shape of the electrode assembly. 
         [0008]    However, if the rechargeable battery with a finishing structure based on the adhesive tape is used for a long period of time, the adhesion of the separators can weaken due to deterioration of the adhesive tape. As a result, the electrode assembly does not hold the initial bonding and the alignment thereof may be broken so that the bonding between the positive and negative electrode plates is weakened and the performance characteristics of the rechargeable battery are significantly deteriorated. 
       SUMMARY 
       [0009]    Embodiments of the present invention have been made in an effort to provide a rechargeable battery having advantages of allowing the electrode assembly to hold an initial fixation characteristic even after long-time usage to achieve high battery durability and long life span characteristics. 
         [0010]    An embodiment of the present invention provides a rechargeable battery comprising: an electrode assembly comprising a plurality of positive electrode plates, a plurality of negative electrode plates, and a plurality of separators; and an case enclosing the electrode assembly; wherein each separator in the plurality of separators comprises a central portion facing at least one of the positive and negative electrode plates and an extended portion that extends past the positive and negative electrode plates, and wherein each of the extended portions comprises an adhered portion that is adhered to adjacent extended portions. 
         [0011]    The extended portions of the separators may further comprise bent portions that are not adhered and that extend from the central portions toward the adhered portions. 
         [0012]    The electrode assembly may have a cross section, and the bent portions are bent from the central portions towards a center of the cross section, and the adhered portions are positioned at the center of the cross section. 
         [0013]    The bent portions may be bent from the central portions towards a plane of a top surface or a bottom surface of the electrode assembly, and the adhered portions are positioned over the plane. 
         [0014]    The adhered portions may be further bent. 
         [0015]    The adhered portions may be further bent in a direction substantially perpendicular to a top surface or a bottom surface of the electrode assembly. 
         [0016]    The electrode assembly may comprise a plurality of stacks of positive electrode plates, negative electrode plates and separators, and wherein the stacks are adhered together by outermost separators on each stack. 
         [0017]    The stacks may be adhered together at the adhered portions of the outermost separators. 
         [0018]    The electrode assembly may comprise a first stack and a second stack, wherein the bent portions of the first stack are bent from the central portions toward a plane of a top surface of the first stack, wherein the bent portions of the second stack are bent from the central portions toward a plane of a bottom surface of the second stack, and wherein the first and second stacks are adhered together such that the adhered portions are positioned at a center of a cross section of the electrode assembly. 
         [0019]    Each electrode plate having the same polarity may be interposed between pairs of separators, and each electrode plate of opposite polarity may be interposed between adjacent pairs of separators. The separators in each pair of separators may be adhered to each other along preliminary adhered portions in the extended portions, and adjacent pairs of separators may be adhered to each other to form the adhered portions. 
         [0020]    The adhered portions of the separators may be smaller than the preliminary adhered portions in length in a direction from the central portions toward an edge of the extended portions. 
         [0021]    The rechargeable battery may further comprise electrode terminals coupled with the electrode assembly on opposite sides of the electrode assembly, wherein the adhered portions of the separators extend from opposite sides of the electrode assembly adjacent to the sides from which the electrode terminals extend. 
         [0022]    The rechargeable battery may further comprise electrode terminals coupled with the electrode assembly on opposite sides of the electrode assembly, wherein the adhered portions of the separators extend from all sides of the electrode assembly except for in the areas from which the electrode terminals extend. 
         [0023]    The adhered portions may extend throughout entire lengths of opposite sides of the electrode assembly. 
         [0024]    The extended portions may extend throughout entire lengths of opposite sides of the electrode assembly, and the adhered portions extend throughout only a part of the lengths of each opposite side of the electrode assembly. 
         [0025]    The adhered portions may be positioned at a center of each opposite side of the electrode assembly. 
         [0026]    The adhered portions may be positioned at ends of each opposite side of the electrode assembly. 
         [0027]    The adhered portions may alternate with extended portions that are not adhered throughout the lengths of each opposite side of the electrode assembly. 
         [0028]    Another embodiment of the present invention provides a method of forming a rechargeable battery comprising: providing an electrode assembly comprising a plurality of positive electrode plates, a plurality of negative electrode plates, and a plurality of separators; and enclosing the electrode assembly with an case; wherein each separator in the plurality of separators comprises a central portion facing at least one of the positive and negative electrode plates and an extended portion that extends past the positive and negative electrode plates, and wherein each of the extended portions comprises an adhered portion that is adhered to adjacent extended portions. 
         [0029]    The adhered portions may be formed by a heat treatment or an ultrasonic process. 
         [0030]    According to an embodiment, the extended portions are welded to each other so as to form adhered portions, thereby simplifying the finishing process of the separators and rigidly bonding the electrode assembly. Accordingly, for the rechargeable battery, the bonding between the positive and the negative electrode plates may be held even after long-time usage so that the alignment thereof can be prevented from being broken and high structural stability and rigidity can be achieved. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]      FIG. 1  is a partial cut-away perspective view of a rechargeable battery according to an embodiment of the present invention. 
           [0032]      FIG. 2  is a perspective view of an electrode assembly and electrode terminals in the rechargeable battery shown in  FIG. 1 . 
           [0033]      FIG. 3  is a partial amplified sectional view of the electrode assembly shown in  FIG. 2 . 
           [0034]      FIG. 4  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
           [0035]      FIG. 5  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
           [0036]      FIG. 6  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
           [0037]      FIG. 7  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
           [0038]      FIG. 8  is a perspective view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
           [0039]      FIG. 9  is a perspective view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
           [0040]      FIG. 10  is a perspective view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
           [0041]      FIG. 11  is a perspective view of an electrode assembly in a rechargeable battery according to another embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0042]    Certain embodiments will now be described more fully hereinafter with reference to the accompanying drawings. 
         [0043]    Embodiments of the present invention will be described more fully hereinafter with reference to the accompanying drawings. 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. 
         [0044]      FIG. 1  is a partial cut-away perspective view of a rechargeable battery according to a first embodiment of the present invention, and  FIG. 2  is a perspective view of an electrode assembly and electrode terminals in the rechargeable battery shown in  FIG. 1 . 
         [0045]    Referring to  FIG. 1  and  FIG. 2 , the rechargeable battery  100  according to the illustrated embodiment includes an electrode assembly  10  with positive electrode plates  11 , separators  20 , and negative electrode plates  12 , a case  30  receiving the electrode assembly  10 , and electrode terminals  41  and  42  connected to the electrode assembly  10  and drawn out of the case  30 . 
         [0046]    The separator  20 , the positive electrode plate  11 , the separator  20 , the negative electrode plate  12 , and the separator  20  may be sequentially and repeatedly laminated so as to form the electrode assembly  10 . In this sequence, the positive electrode plate  11  may be replaced by the negative electrode plate  12  and the negative electrode plate  12  by the positive electrode plate  11 . One sheet of the separators  20  may be disposed between the positive and negative electrode plates  11  and  12  such that two sheets of the separators  20  do not overlap each other. 
         [0047]    The electrode terminals  41  and  42  may include a positive electrode terminal  41  connected to the positive electrode plates  11 , and a negative electrode terminal  42  connected to the negative electrode plates  12 . The positive and negative electrode plates  11  and  12  may include current collecting regions  13  and  14 , respectively, which are protruded to the outside of the separators  20  and tightly adhered to each other through pressurizing them. The positive and negative electrode terminals  41  and  42  may be connected to the current collecting region  13  of the positive electrode plates  11  and the current collecting region  14  of the negative electrode plates  12 , respectively. 
         [0048]    The positive and negative electrode terminals  41  and  42  may be drawn out to one side of the case  30  or to both sides thereof.  FIG. 1  and  FIG. 2  illustrate the case in which the current collecting region  13  of the positive electrode plates  11  and the current collecting region  14  of the negative electrode plates  12  are formed opposite to each other, and the positive and negative electrode terminals  41  and  42  are drawn out to both sides of the case  30 . 
         [0049]    The case  30  may include an upper case  31  with a concave center, and a lower case  32 . The upper and lower cases  31  and  32  may be formed with laminate sheets. The upper and lower cases  31  and  32  can receive an electrolyte-impregnated electrode assembly  10  therein, and may be adhered, e.g., thermally welded, to each other at the edges thereof so as to seal the electrode assembly  10 . The shape and material of the case  30  are not limited to as above-described, but may be altered in various manners. 
         [0050]    The electrode assembly  10  may be roughly formed in the shape of a rectangular solid. The electrode assembly  10  can include a pair of first sides  101  facing each other in a first direction (in the y axis direction), and a pair of second sides  102  facing each other in a second direction (in the x axis direction). The current collecting regions  13  and  14  and the electrode terminals  41  and  42  may be placed on at least one of the pair of first sides  101 . The first sides  101  may be the short sides of the electrode assembly  10 , and the second sides  102  may be the long sides thereof. 
         [0051]      FIG. 3  is a partial amplified sectional view of the electrode assembly shown in  FIG. 2 . 
         [0052]    Referring to  FIG. 1  to  FIG. 3 , the separators  20  can each include a center  21  facing at least one of the positive and negative electrode plates  11  and  12  and overlapped therewith, and a pair of extensions, including bent portions  22  and adhered portions  23 , extended from the center  21  to the outside of the positive and negative electrode plates  11  and  12 . The pair of extensions, including portions  22  and  23 , may be placed at the second sides  102  where the current collecting regions  13  and  14  and the electrode terminals  41  and  42  are absent. 
         [0053]    The extensions may be overlapped with each other at the second sides  102 , and may be tightly adhered to each other at the edges thereof in a body so as to form adhered portions  23 . The adhered portions  23  may be formed by melting and pressing the surfaces of the separators  20  together, for example, through thermal welding or ultrasonic welding, such that the positive and negative electrode plates  11  and  12  are stably fixed between the centers  21  of the separators  20 . 
         [0054]    The adhered portions  23  are connected to the bent portions  22  of all the separators  20  provided in the electrode assembly  10  so as to bind them into one. That is, a single adhered portion  23  may exist in the thickness direction of the electrode assembly  10  (in the z axis direction). Consequently, the finishing process of the separators  20  can be simplified, and the bonding of the electrode assembly  10  may become reinforced overall. The adhered portions  23  can have excellent adhesive strength and air tightness, and hence the extensions may not be separated from each other even after long-time usage so that the durability of the rechargeable battery  100  may be effectively improved. 
         [0055]    The extensions may be symmetrically gathered in the thickness direction of the electrode assembly  10  (in the z axis direction) so that the adhered portion  23  can be formed at the center of the electrode assembly  10  in the thickness direction of the electrode assembly  10  (in the z axis direction). In this case, the adhered portion  23  may be formed while uniformly pressurizing the extensions so that the shape stability of the electrode assembly  10  can be enhanced. 
         [0056]    The adhered portions  23  may be provided at the second sides  102  with a longer length than that of the first sides  101 . Accordingly, the bonded area can become enlarged along the edge of the electrode assembly  10 , and the fixation of the electrode assembly  10  can be enhanced. Particularly, as the adhered portions  23  have the same length as the second sides  102 , the fixation of the electrode assembly  10  can be maximized. 
         [0057]    In this way, with the rechargeable battery  100  according to the first embodiment, the electrode assembly  10  can rigidly bond the extensions of the separators  20  over the entire area of the pair of second sides  102  by way of the adhered portions  23 . Consequently, even after long-time usage of the rechargeable battery  100 , the bonding of the positive and negative electrode plates  11  and  12  may be maintained therebetween so that the alignment thereof is prevented from being broken, thereby securing high structural stability and rigidity. 
         [0058]      FIG. 4  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to a second embodiment of the present invention. 
         [0059]    Referring to  FIG. 4 , the rechargeable battery according to the second illustrated embodiment has the same structural components as those of the rechargeable battery according to the first illustrated embodiment, except that extensions, including bent portions  221  and adhered portions  231 , are asymmetrically gathered in the thickness direction of the electrode assembly  110  (in the z axis direction), and an adhered portion  231  is biased to one side of the electrode assembly  110  in the thickness direction of the electrode assembly  110  (in the z axis direction). 
         [0060]    Reference numeral  201  of  FIG. 4  refers to the separator, and reference numeral  211  refers to the center of the separator. The same reference numerals as with the rechargeable battery according to the first illustrated embodiment are used to refer to the structural components other than the separator. 
         [0061]    The extensions according to the second illustrated embodiment may be gathered toward the outermost extension, and the adhered portion  231  may be located at the extended top or bottom side of the electrode assembly  110 . It is illustrated in  FIG. 4  that the adhered portion  231  is located at the extended bottom side of the electrode assembly  110 . 
         [0062]    The extensions may be disposed between a pair of heating plates (not shown) provided at a welder, and pressurized and welded by way of the heating plates so as to form adhered portions  231 . In this process, for the first illustrated embodiment, the pair of heating plates can simultaneously move so as to form the adhered portions  23 , whereas for the second illustrated embodiment, only one heating plate can move while the other heating plate is fixed so as to form the adhered portions  231 . Therefore, the case according to the second embodiment is more suitable for mass production. 
         [0063]      FIG. 5  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to a third embodiment of the present invention. 
         [0064]    Referring to  FIG. 5 , the rechargeable battery according to the third illustrated embodiment may have the same structural components as those of the rechargeable battery according to the second illustrated embodiment, except that an adhered portion  232  may be biased to one side of the electrode assembly  120  in the thickness direction of the electrode assembly  120  (in the z axis direction), i.e., to the lower side of  FIG. 5 , while being bent to the other side of the electrode assembly  120 , i.e., to the upper side of  FIG. 5 , so as to form a folded portion  24  at the end thereof. 
         [0065]    Reference numeral  202  of  FIG. 5  refers to the separator, reference numeral  212  refers to the center of the separator, and reference numeral  222  refers to the bended portions of the extension of the separator. The same reference numerals as with the rechargeable battery according to the second illustrated embodiment are used to refer to the structural components other than the separator. 
         [0066]    As the width of the adhered portion  232  is increased, the bonding area of the extensions is enlarged so that the bonding between the separators  202  is reinforced. However, because the adhered portion  232  of the electrode assembly  120  participates in battery reaction, when the width of the adhered portion  232  is increased in comparison with the same-dimensioned case  30 , the electrode area can be reduced. 
         [0067]    In this connection, for the structure where the adhered portion  232  is bent so as to form a bent portion  24  parallel to the thickness direction of the electrode assembly  10  (in the z axis direction), the area of the positive and negative electrode plates  11  and  12  can be widened in comparison with the same-dimensioned case  30  while enlarging the width of the adhered portion  232  to reinforce the bonding between the separators  202 , thereby enhancing battery efficiency. 
         [0068]      FIG. 6  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to a fourth embodiment of the present invention. 
         [0069]    Referring to  FIG. 6 , the rechargeable battery has the same structural components as those of the rechargeable battery according to the first illustrated embodiment of the present invention, except that the electrode assembly  130  has a laminate structure with a first electrode assembly part  131  having at least one positive electrode plate  11 , at least one negative electrode plate  12 , and a preliminary adhered portion  25 , and a second electrode assembly part  132  having at least one positive electrode plate  11 , at least one negative electrode plate  12 , and a preliminary adhered portion  25 . The preliminary adhered portion  25  of the first electrode assembly part  131  and the preliminary adhered portion  25  of the second electrode assembly part  132  are again adhered so as to form a adhered portion  233 . 
         [0070]    It is illustrated in  FIG. 6  that the electrode assembly  130  includes two electrode assembly parts  131  and  132 , but the rechargeable battery according to the fourth illustrated embodiment may include three electrode assembly parts or more, each with a preliminary adhered portion  25 , and the preliminary adhered portions  25  of the electrode assembly parts may be again adhered so as to form a adhered portion  233 . 
         [0071]    Reference numeral  203  of  FIG. 6  refers to the separator, reference numeral  213  refers to the center of the separator, and reference numeral  223  refers to bent portions of the extension of the separator. The same reference numerals as with the rechargeable battery according to the first illustrated embodiment are used to refer to the structural components other than the separator  203 . 
         [0072]    The edges of the separators  203  may be adhered to each other with respect to the respective first and second electrode assembly parts  131  and  132  to form preliminary adhered portions  25 . The first and second electrode assembly parts  131  and  132  may be laminated, and the two preliminary adhered portions  25  may be adhered to each other so as to form the adhered portion  233 . In this case, two separators  203  exist at the contact area of the first and second electrode assembly parts  131  and  132 . That is, the outermost separator of one of the electrode assembly parts may be overlapped with the outermost separator of the other electrode assembly part. 
         [0073]    In this way, when the electrode assembly  130  is divided into two parts or more and preliminary adhered portions  25  are formed, the electrode assembly  130  may be effectively prevented from being distorted or defective during the welding process, thereby enhancing the quality of the electrode assembly  130 .  FIG. 6  illustrates that the first and second electrode assembly parts  131  and  132  are provided with six sheets of separators  203 , but the number of separators  203  contained in the respective electrode assembly parts is not limited to as illustrated. 
         [0074]      FIG. 7  is a partial amplified sectional view of an electrode assembly in a rechargeable battery according to a fifth embodiment of the present invention. 
         [0075]    Referring to  FIG. 7 , the rechargeable battery according to the fifth illustrated embodiment has the same structural components as those of the rechargeable battery according to the first illustrated embodiment, except that the electrode assembly  140  has a laminate structure with a plurality of constructions each having one positive electrode plate  11  or negative electrode plate  12 , two sheets of separators  204 , and a preliminary adhered portion  251 , and a plurality of negative electrode plates  12  or positive electrode plates  11  disposed between the constructions while being tightly adhered thereto. The preliminary adhered portions  251  laminated by the number of constructions  141  may again be welded to each other so as to form a adhered portion  234 . 
         [0076]    Reference numeral  214  of  FIG. 7  refers to the center of the separator, and reference numeral  224  the extension of the separator. The same reference numerals as for the rechargeable battery according to the first illustrated embodiment are used to refer to the structural components other than the separator  204 . 
         [0077]    A positive electrode plate  11  or negative electrode plate  12  may be disposed between two sheets of separators  204 , and the edges of the two separator extensions  224  may be adhered to each other so as to form the preliminary adhered portion  251 . In this way, a plurality of constructions  141  may be formed and sequentially laminated together with a plurality of negative electrode plates  12  or positive electrode plates  11 . The laminated preliminary adhered portions  251  may be again adhered to each other so as to form the adhered portion  234 . In this case, the length L 1  of the preliminary adhered portion  251  measured at each construction  141  may be larger than the length L 2  of the adhered portion  234  measured at the electrode assembly  140  as a whole. 
         [0078]    As described above, when the electrode assembly  140  is formed with a plurality of constructions  141 , the electrode assembly  140  is prevented from being distorted or defective during the welding process, thereby enhancing the quality of the electrode assembly, as with the fourth illustrated embodiment. 
         [0079]      FIG. 8  is a perspective view of an electrode assembly in a rechargeable battery according to a sixth embodiment of the present invention. 
         [0080]    Referring to  FIG. 8 , the rechargeable battery according to the sixth illustrated embodiment has the same structural components as those of the rechargeable battery according to any one of the first to fifth illustrated embodiments of the present invention, except that extensions  22  may be formed at the first sides  101  of the electrode assembly  150  except for the current collecting regions  13  and  14  as well as at the second sides  102  of the electrode assembly  150 , and an adhered portion  23  may be formed at the edge of each extension  22 .  FIG. 8  illustrates the case in which the features according to the sixth illustrated embodiment are combined with the structure according to the first illustrated embodiment. 
         [0081]    With the sixth illustrated embodiment, the adhered portions  23  are formed over the entire area of the first sides  101  except for the current collecting regions  13  and  14 , and the second sides  102 . Accordingly, compared with the first to fifth illustrated embodiments, the bonded area along the edge of the electrode assembly  150  may be enlarged so as to achieve excellent structural stability and rigidity. 
         [0082]      FIG. 9  is a perspective view of an electrode assembly in a rechargeable battery according to a seventh illustrated embodiment of the present invention. 
         [0083]    Referring to  FIG. 9 , the rechargeable battery according to the seventh illustrated embodiment has the same structural components as those of the rechargeable battery according to any one of the first to fifth illustrated embodiments, except that the adhered portion  235  has a shorter length than that of the second side  102  and is located at the center of the second side  102 .  FIG. 9  illustrates the case in which the features according to the seventh illustrated embodiment are combined with the structure according to the first illustrated embodiment. 
         [0084]      FIG. 10  is a perspective view of an electrode assembly in a rechargeable battery according to an eighth embodiment of the present invention. 
         [0085]    Referring to  FIG. 10 , the rechargeable battery according to the eighth illustrated embodiment has the same structural components as those of the rechargeable battery according to any one of the first to fifth illustrated embodiments, except that two adhered portions  236  are formed at the respective second sides  102  while being spaced apart from each other by a distance.  FIG. 10  illustrates the case in which the features according to the eighth illustrated embodiment are combined with the structure according to the first illustrated embodiment. 
         [0086]    With the electrode assemblies  160  and  170  according to the seventh and eighth illustrated embodiments, the extensions  22  are laminated through pressurizing at the second sides  102  except for the adhered portions  235  and  236 , but are not adhered so that a predetermined gap is formed between the laminated extensions  22 . 
         [0087]    When the rechargeable batteries according to the seventh and eighth illustrated embodiments are compared with the rechargeable batteries according to the first to sixth illustrated embodiments, the adhered portions  235  and  236  have a shorter length than that of the second sides  102  so that the electrode assemblies  160  and  170  have lowered rigidity, but they have enhanced electrolyte impregnation characteristic as the electrode assemblies  160  and  170  are easily impregnated with the electrolyte through the gap between the extensions  22 . 
         [0088]      FIG. 11  is a perspective view of an electrode assembly in a rechargeable battery according to a ninth illustrated embodiment of the present invention. 
         [0089]    Referring to  FIG. 11 , the rechargeable battery according to the ninth illustrated embodiment has the same structural components as those of the rechargeable battery according to any one of the first to fifth illustrated embodiments, except that three or more adhered portions  237  are formed at the respective second sides  102  while being spaced apart from each other by a distance.  FIG. 11  illustrates the case in which the features according to the ninth illustrated embodiment are combined with the structure according to the first illustrated embodiment. 
         [0090]    With the electrode assembly  180  according to the ninth illustrated embodiment, the extensions  22  are laminated through pressurizing at the second sides  102  except for the adhered portions, but are not adhered so that a predetermined gap is formed between the laminated extensions  22 . 
         [0091]    Three or more adhered portions  237  are formed at the second side  102  while being spaced apart from each other by a distance so that uniform fixation occurs in the longitudinal direction of the second side  102 , and the electrode assembly  180  is uniformly impregnated with the electrolyte through the gap between the laminated extensions  22 . Accordingly, the rechargeable battery according to the ninth illustrated embodiment properly has excellent rigidity that is the advantage of the rechargeable batteries according to the first to sixth illustrated embodiments, and an excellent electrolyte impregnation characteristic that is the advantage of the rechargeable batteries according to the seventh and eighth illustrated embodiments. 
         [0092]    While this invention 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.
A rechargeable battery comprises: an electrode assembly comprising a plurality of positive electrode plates, a plurality of negative electrode plates, and a plurality of separators; and a case enclosing the electrode assembly; wherein each separator in the plurality of separators comprises a central portion facing at least one of the positive and negative electrode plates, and an extended portion that extends past the positive and negative electrode plates, and wherein each of the extended portion comprises an adhered portion that is adhered to adjacent extended portions.