Abstract:
A rechargeable battery including an electrode assembly including a first surface; a case containing the electrode assembly and an electrolyte solution; a cap plate covering an opening of the case and including a first surface spaced apart in a first direction from and facing the first surface of the electrode assembly; and an electrolyte solution absorption member inside the case and located between the first surface of the electrode assembly and the first surface of the cap plate in the first direction, the electrolyte solution absorption member configured to absorb a portion of the electrolyte solution.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of U.S. Provisional Application No. 61/809,798, filed on Apr. 8, 2013 in the U.S. Patent and Trademark Office, the entire content of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    Aspects of embodiments of the present invention relate to a rechargeable battery. 
         [0004]    2. Description of the Related Art 
         [0005]    A rechargeable battery is a battery that can be charged and discharged, unlike a primary battery that cannot be charged. A low-capacity rechargeable battery has been used for small portable electronic devices, such as a mobile phone, a laptop computer, and a camcorder, and a large-capacity battery has been used as a power supply for driving a motor, such as for an electric vehicle, a hybrid vehicle, and the like, or a large-capacity power storage device. 
         [0006]    In recent years, a high-output rechargeable battery using a non-aqueous electrolytic solution having a high energy density has been developed. The high-output rechargeable battery is configured as a large-capacity battery module by connecting a plurality of rechargeable batteries in series to be able to be used to drive a motor of a device requiring large power, such as an electric vehicle, and the like. The rechargeable battery may be formed having a shape of a cylinder, a square, or the like. 
         [0007]    In order to smoothly operate the rechargeable battery, an appropriate amount of electrolytic solution needs to be filled or injected into an electrode assembly of the rechargeable battery. 
         [0008]    Therefore, an amount of the electrolytic solution injected into the rechargeable battery may be more than an amount of the electrolytic solution appropriately filled into an electrode assembly, or an electrolytic solution equal to an amount of the electrolytic solution appropriately filled into the electrode assembly may be injected into a case. 
         [0009]    However, when the electrolytic solution is larger than the amount of the electrolytic solution appropriately filled into the electrode assembly, a residual electrolytic solution E that is not contained within the electrode assembly is generated in the case, and may thereby cause a short circuit in the case. 
         [0010]    Further, in order to inject the electrolytic solution equal to the amount of the electrolytic solution appropriately filled into the electrode assembly into the rechargeable battery, there is a need to stop injecting the electrolytic solution and then measure the amount of the electrolytic solution supplied to the rechargeable battery, such that an injection process time of the electrolytic solution may be increased. 
       SUMMARY 
       [0011]    According to an aspect of embodiments of the present invention, an absorption member is capable of absorbing a residual electrolytic solution in a rechargeable battery and shortening an injection process time of the electrolytic solution. According to another aspect of embodiments of the present invention, a rechargeable battery includes a structure capable of minimizing or reducing a residual electrolytic solution in a case. 
         [0012]    According to one or more embodiments of the present invention, a rechargeable battery includes: an electrode assembly including a first surface; a case containing the electrode assembly and an electrolyte solution; a cap plate covering an opening of the case and including a first surface spaced apart in a first direction from and facing the first surface of the electrode assembly; and an electrolyte solution absorption member inside the case and located between the first surface of the electrode assembly and the first surface of the cap plate in the first direction, the electrolyte solution absorption member configured to absorb a portion of the electrolyte solution. 
         [0013]    The electrolyte solution absorption member may be made of an insulating material. 
         [0014]    The electrolyte solution absorption member may include an electrolyte solution absorbing material. 
         [0015]    The electrolyte solution absorption member may be attached to the cap plate via an adhesive. 
         [0016]    The electrolyte solution absorption member may include a thin plate or sheet. 
         [0017]    The electrolyte solution absorption member may include a porous film or a fiber fabric. 
         [0018]    The electrolyte solution absorption member may have a plurality of nano-sized openings. 
         [0019]    The electrolyte solution absorption member may include a porous film of at least one of polyolefin or polyvinylidene fluoride. 
         [0020]    The rechargeable battery may further include a terminal electrically coupled to the electrode assembly and protruding through the cap plate, and the electrolyte solution absorption member may have a first opening through which the terminal passes. 
         [0021]    The cap plate may have an electrolyte injection opening, and the electrolyte solution absorption member may have a third opening at a location corresponding to the electrolyte injection opening of the cap plate. 
         [0022]    The cap plate may have a vent opening, and the electrolyte solution absorption member may have a fourth opening at a location corresponding to the vent opening of the cap plate. 
         [0023]    The electrolyte solution absorption member may be coupled to the first surface of the cap plate. The rechargeable battery may further include an auxiliary electrolyte solution absorption member inside the case and coupled to a side wall of the case. 
         [0024]    The auxiliary electrolyte solution absorption member may be on a portion of the side wall of the case at a location between the first surface of the electrode assembly and the first surface of the cap plate in the first direction. 
         [0025]    The auxiliary electrolyte solution absorption member may have a ring shape corresponding to a shape of an inner surface of the side wall of the case. 
         [0026]    The electrolyte solution absorption member may include a flat portion and a protruding portion surrounding a periphery of the flat portion. 
         [0027]    The flat portion may be coupled to the first surface of the cap plate, and the protruding portion may protrude in a direction toward the first surface of the electrode assembly. The protruding portion may protrude from an edge of the flat portion. 
         [0028]    The protruding portion may contact an inner surface of a side wall of the case. 
         [0029]    A surface of the protruding portion facing the first surface of the electrode assembly may be angled with respect to the flat portion. 
         [0030]    According to one or more embodiments of the present invention, a rechargeable battery includes an electrode assembly, a case for mounting the electrode assembly and an electrolyte solution therein, and a cap plate for closing an opening of the case, and an electrolyte solution absorption member is provided inside the case coupled to the cap plate. 
         [0031]    According to an aspect of embodiments of the present invention, the residues of the electrolytic solution in the case can be minimized or reduced by the absorption member disposed in the case to absorb the residual electrolytic solution to prevent or substantially prevent an internal short circuit from occurring due to the residual electrolytic solution and shortening the operation time for controlling an amount of the residual electrolytic solution in the case, thereby improving the productivity of the rechargeable battery. 
         [0032]    In an exemplary embodiment, the absorption member is provided on the surface of the cap plate facing the electrode assembly. In this way, the electrolyte solution can be absorbed at a location spaced apart from the electrode assembly, thereby reducing the risk of a short circuit. 
         [0033]    In one exemplary embodiment, the electrolyte solution absorption member is attached to the cap plate via an adhesive, thereby simplifying the assembly of the battery and the fixing of the electrolyte solution absorption member to the cap plate. 
         [0034]    In one embodiment, the electrolyte solution absorption member includes or consists of an electrolyte solution absorbing material. That is, the material of the electrolyte solution absorption member provides the electrolyte solution absorbing effect more than the shape of the electrolyte solution absorption member. In an exemplary embodiment, the electrolyte solution absorption member includes a porous film or a fiber fabric. The porous film and the fiber fabric may be formed of at least one of porous materials, and may have a plurality of nano-sized openings to absorb and contain an electrolyte solution therein. The porous film may be formed of at least one of polyolefin and polyvinylidene fluoride. 
         [0035]    The electrolyte solution absorption member, in an exemplary embodiment, is a thin absorption sheet. 
         [0036]    The battery may further include a first terminal rivet coupled to a first electrode of the electrode assembly and protruding from the inside of the case through the cap plate, and the electrolyte solution absorption member may include a first groove for passing the first terminal rivet therethrough. 
         [0037]    In one embodiment, the rechargeable battery may further include a second terminal rivet coupled to a second electrode of the electrode assembly and protruding from the inside of the case through the cap plate, and the electrolyte solution absorption member may include a second groove for passing the second terminal rivet therethrough. 
         [0038]    The cap plate may include an electrolyte injection port, and the electrolyte solution absorption member may include an electrolyte injection port groove formed at a location corresponding to the location of the electrolyte injection port. 
         [0039]    The cap plate may include a vent hole, and the electrolyte solution absorption member may include a vent hole groove formed at a location corresponding to the location of the vent hole. 
         [0040]    The rechargeable battery may further include an auxiliary electrolyte solution absorption member coupled to at least one side surface of the case at a vertical location above the electrode assembly and below the cap plate. 
         [0041]    The auxiliary electrolyte solution absorption member, in an exemplary embodiment, includes an electrolyte solution absorbing material, and may be a similar electrolyte solution absorbing material as the electrolyte solution absorption member. 
         [0042]    The auxiliary electrolyte solution absorption member may have a shape of a ring or a shape corresponding to a lateral cross-section of the case and may be fixed or laminated to the interior of the case. 
         [0043]    The electrolyte solution absorption member may comprise a flat part, and a protruding part protruding in a direction away from the cap plate toward the electrode assembly. 
         [0044]    The protruding part may protrude along an edge of the flat part, and the flat part may be coupled to the cap plate. The protruding part may form a closed curve on the edge of the flat part. An inner circumference of the protruding part may be angled with respect to the flat part. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0045]    The accompanying drawings, together with the specification, illustrate some exemplary embodiments of the present invention, and, together with the description, serve to explain principles and aspects of the present invention. 
           [0046]      FIG. 1  is a perspective view of a rechargeable battery according to an exemplary embodiment of the present invention. 
           [0047]      FIG. 2  is a cross-sectional view of the rechargeable battery of  FIG. 1 , taken along the line II-II. 
           [0048]      FIG. 3  is a partial exploded perspective view of the rechargeable battery of  FIG. 1 . 
           [0049]      FIG. 4  is a bottom perspective view illustrating a state in which an absorption member and a cap plate of the rechargeable battery of  FIG. 1  are coupled with each other. 
           [0050]      FIG. 5  is a cross-sectional view illustrating a state in which a residual electrolytic solution in the rechargeable battery of  FIG. 1  is absorbed in the absorption member of  FIG. 4 . 
           [0051]      FIG. 6  is a partial exploded perspective view of a rechargeable battery according to another exemplary embodiment of the present invention. 
           [0052]      FIG. 7  is a cross-sectional view of the rechargeable battery of  FIG. 6 , taken along the line VII-VII, illustrating a state in which a residual electrolytic solution is absorbed in an absorption member. 
           [0053]      FIG. 8  is a partial exploded perspective view of a rechargeable battery according to another exemplary embodiment of the present invention. 
           [0054]      FIG. 9  is a cross-sectional view of the rechargeable battery of  FIG. 8 , taken along the line IX-IX, illustrating a state in which a residual electrolytic solution is absorbed in an absorption member. 
           [0055]      FIG. 10  is a cross-sectional view of the rechargeable battery of  FIG. 8 , taken along the line X-X, illustrating a state in which a residual electrolytic solution is absorbed in an absorption member. 
       
    
    
     DETAILED DESCRIPTION 
       [0056]    In the following detailed description, certain exemplary embodiments of the present invention have been shown and described, simply by way of illustration. 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. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive. 
         [0057]      FIG. 1  is a perspective view illustrating a rechargeable battery according to an exemplary embodiment of the present invention; and  FIG. 2  is a cross-sectional view of the rechargeable battery of  FIG. 1 , taken along the line II-II. 
         [0058]    Further,  FIG. 3  is a partial exploded perspective view of the rechargeable battery of  FIG. 1 ; and  FIG. 4  is a bottom perspective view illustrating a state in which an absorption member and a cap plate of the rechargeable battery of  FIG. 1  are coupled with each other. 
         [0059]      FIG. 5  is a cross-sectional view illustrating a state in which a residual electrolytic solution in the rechargeable battery of  FIG. 1  is absorbed in the absorption member of  FIG. 4 . 
         [0060]    Referring to  FIGS. 1 and 2 , a rechargeable battery  100  according to an exemplary embodiment of the present invention includes an electrode assembly  10 , a case  25  in which the electrode assembly  10  is embedded or contained, a first terminal part  30  and a second terminal part  40  that are electrically connected with the electrode assembly  10 , a cap plate  20 , first and second lower insulating members  60  and  80 , and an electrolyte solution absorption member  90 , or absorption member  90 , that is coupled with the cap plate  20 . 
         [0061]    The rechargeable battery  100  according to an exemplary embodiment of the present invention is a lithium ion rechargeable battery and will be described as a square or prismatic rechargeable battery, by way of example. However, embodiments of the present invention are not limited thereto, but may be applied to a battery, such as a lithium polymer battery, and the like. 
         [0062]    The electrode assembly  10  according to an embodiment of the present invention has a jelly roll form in which a first electrode  11 , a second electrode  12 , and a separator  13  are wound. 
         [0063]    Further, a surface of the electrode assembly  10  according to an embodiment of the present invention may be coupled with an insulating tape  14  to insulate the electrode assembly  10  from the case  25 . 
         [0064]    According to an embodiment of the present invention, the first electrode  11  is a negative electrode, and the second electrode  12  is a positive electrode. 
         [0065]    However, the present invention is not limited thereto, and, in another embodiment, the first electrode  11  may be used as a positive electrode, and the second electrode  12  may be as a negative electrode. 
         [0066]    The first electrode  11  is wound to be disposed at an outermost side of the electrode assembly  10  according to an embodiment of the present invention. 
         [0067]    In addition, the first electrode  11  and the second electrode  12  are partitioned into a coated part in which a current collector is coated with an active material, and a first electrode uncoated part  11   a  and a second electrode uncoated part  12   a  that are disposed at opposite sides of the coating part in the jelly roll state and on which the current collector is not coated with the active material. 
         [0068]    The first electrode uncoated part  11   a  of the electrode assembly  10  is electrically connected with the first terminal part  30  via a first electrode current collecting member  50 , and the second electrode uncoated part  12   a  is electrically connected with the second terminal part  40  via a second electrode current collecting member  70 . 
         [0069]    Further, the first and second terminal parts  30  and  40  include first and second rivets  31  and  41 , first and second terminal plates  32  and  42 , a first terminal insulating member  33  that is disposed between the first terminal plate  32  and the cap plate  20 , a second connection plate  43  that is disposed between the second terminal plate  42  and the cap plate  20 , and first and second gaskets  34  and  44 . 
         [0070]    The second terminal plate  42  according to an embodiment of the present invention is made of a conductive material. 
         [0071]    In addition, the cap plate  20  according to an embodiment of the present invention has a thin panel or plate shape and is made of a conductive material and coupled with an opening of the case  25  to seal the opening. 
         [0072]    The cap plate  20  is provided with an electrolyte injection port  21  through which an electrolytic solution is injected into the sealed case  25 , and the electrolyte injection port  21  is used to inject the electrolytic solution and then is sealed by a sealing stopper  22 . 
         [0073]    The cap plate  20 , in one embodiment, is provided with a vent hole  23  that is provided with a vent plate  24  that is fractured when an internal pressure of the sealed case  25  exceeds a certain pressure (e.g., a predetermined pressure). 
         [0074]    The cap plate  20  according to an embodiment of the present invention may be electrically connected with the second electrode  12  via the second terminal plate  42 , the second connection plate  43 , and the second electrode current collecting member  70 . 
         [0075]    The case  25 , in one embodiment, has a substantially rectangular parallelepiped shape and is made of a conductive material, and one surface of the case  25  is provided with an opening through which the electrode assembly  10  is inserted. 
         [0076]    In addition, the case  25  according to an embodiment of the present invention may be electrically connected with the second electrode  12  via the cap plate  20 . 
         [0077]    However, embodiments of the present invention are not limited thereto, but the case may be formed in various shapes, such as a cylindrical shape, a pouch shape, and the like. 
         [0078]    Further, the first and second lower insulating members  60  and  80  are disposed to be adjacent to the cap plate  20  within the case  25 . 
         [0079]    Referring to  FIGS. 3 and 4 , the absorption member  90  according to an exemplary embodiment of the present invention is coupled with a surface of the cap plate  20  that faces the inside of the case  25 . 
         [0080]    The absorption member  90  according to an exemplary embodiment of the present invention has a thin plate shape and is made of an absorbing material and an insulating material. 
         [0081]    In addition, the absorbing member  90  according to an embodiment of the present invention includes a first groove  91 , a second groove  92 , a third groove  93 , and a fourth groove  94 . 
         [0082]    The first groove  91  of the absorbing member  90  according to an embodiment of the present invention is coupled with the first lower insulating member  60 , and the second groove  92  is coupled with the second lower insulating member  80 . 
         [0083]    Further, the third groove or electrolyte injection port groove  93  of the absorbing member  90  according to an embodiment of the present invention is formed at a place facing the electrolyte injection port  21  such that the electrolyte injection port  21  is exposed within the case  25 . 
         [0084]    In addition, the fourth groove or vent hole groove  94  of the absorbing member  90  according to an embodiment of the present invention is formed at a place facing the vent hole  23  such that the vent hole  23  is exposed within the case  25 . 
         [0085]    A residual electrolytic solution E is absorbed in the absorbing member  90  to prevent or substantially prevent a short circuit, as described below in further detail. 
         [0086]      FIG. 5  is a cross-sectional view illustrating the state in which the residual electrolytic solution E in the rechargeable battery  100  is absorbed in the absorption member  90 . 
         [0087]    Referring to  FIGS. 2 and 5 , the absorption member  90  according to an exemplary embodiment of the present invention may be coupled with a surface of the cap plate  20  facing the electrode assembly  10  to be disposed between the electrode assembly  10  and the cap plate  20 . 
         [0088]    In order to smoothly operate the electrode assembly  10 , an appropriate amount of the electrolytic solution needs to be filled or inserted into the electrode assembly  10 . 
         [0089]    Therefore, the amount of the electrolytic solution injected into the case  25  may be more than the amount of the electrolytic solution appropriately filled into the electrode assembly  10 . 
         [0090]    When the amount of the electrolytic solution injected into the case  25  is more than the amount of the electrolytic solution appropriately filled into the electrode assembly  10 , as illustrated in  FIG. 2 , the residual electrolytic solution E that is not contained within the electrode assembly  10  is generated within the case  25 . 
         [0091]    The residual electrolytic solution E may be a factor that causes a short circuit within the case  25 . 
         [0092]    That is, the first electrode  11  is disposed at an outermost side of the electrode assembly  10  according to an embodiment of the present invention, and the case  25  is electrically connected with the second electrode  12  via the cap plate  20 . 
         [0093]    Further, the residual electrolytic solution E is disposed between the first electrode  11  and a bottom surface of the case  25 . 
         [0094]    In this case, the first electrode  11  and the case  25  may maintain a state in which the first electrode  11  and the case  25  are not electrically connected with each other by the insulating tape  14 , that is, an insulating state. 
         [0095]    However, the insulating tape  14  that is coupled with the surface of the electrode assembly  10  may be damaged due to external impact, heat generated from the inside of the case  25 , and the like. 
         [0096]    Therefore, when the insulating tape  14  is damaged due to external impact, heat, and the like, such that the first electrode  11  is electrically connected with the case  25  via the residual electrolytic solution E that is stagnated in the bottom of the case  25  disposed at a side facing the cap plate  20 , a current path is formed between the first electrode  11  and the second electrode  12  to cause a short circuit within the case  25 . 
         [0097]    The absorption member  90  according to an exemplary embodiment of the present invention may prevent or substantially prevent a short circuit from occurring within the case  25  due to the residual electrolytic solution E. 
         [0098]    As illustrated in  FIG. 5 , when the case  25  is rotated clockwise or counterclockwise or inverted such that the cap plate  20  faces a gravity direction, or, in other words, a normal to the cap plate  20  pointing away from the case  25  is parallel to the direction of gravity, the residual electrolytic solution E remaining in the case  25  is absorbed in the absorption member  90  disposed in the case  25 . 
         [0099]    The absorption member  90  according to an exemplary embodiment of the present invention is made of a material that may appropriately absorb the residual electrolytic solution E. 
         [0100]    Consequently, according to an exemplary embodiment of the present invention, since the residual electrolytic solution E is absorbed in the absorption member  90 , it is possible to prevent or substantially prevent a short circuit from occurring within the case  25  by the residual electrolytic solution E even when the insulating tape  14  is damaged. 
         [0101]    Further, in order to prevent or substantially prevent the residual electrolytic solution E from occurring within the case  25 , an amount equal to the amount of the electrolytic solution appropriately filled into the electrode assembly  10  may be injected into the case  25 . 
         [0102]    However, in a comparable process, in order to inject the electrolytic solution into the case  25  in the amount of electrolytic solution appropriately filled into the electrode assembly  10 , there would be a need to stop injecting the electrolytic solution and then measure the amount of the electrolytic solution supplied into the case  25 . 
         [0103]    Therefore, in a comparable process, in order to prevent or substantially prevent the residual electrolytic solution E from occurring within the case  25 , the injection of the electrolytic solution would needs to stop or the injection speed of the electrolytic solution would need to be delayed, such that an injection process time of the electrolytic solution would be increased. 
         [0104]    However, according to exemplary embodiments of the present invention, there is no need to measure the injected amount of the electrolytic solution enough to prevent or substantially prevent the residual electrolytic solution E from occurring within the case  25 . 
         [0105]    That is, according to exemplary embodiments of the present invention, even though the residual electrolytic solution E is generated due to the supply of the electrolytic solution into the case  25 , the residual electrolytic solution E may be removed by the absorption member  90 , such that there is no need to measure the injected amount of the electrolytic solution as in a comparable process. 
         [0106]    The absorption member  90 , in an exemplary embodiment, is attached to the cap plate  20  via an adhesive. Furthermore, the absorption member  90  may comprise or consist of an electrolyte solution absorbing material. The electrolyte solution absorption member  90  may comprise a porous film or a fiber fabric. The porous film and the fiber fabric may be formed of at least one of porous materials and may have a plurality of nano-sized openings to absorb and contain an electrolyte solution therein. In one embodiment, the porous film may be formed of at least one of polyolefin and polyvinylidene fluoride. 
         [0107]    Therefore, according to exemplary embodiments of the present invention, there is no need to stop injecting the electrolytic solution or delay the injection speed of the electrolytic solution in order to measure the injected amount of the electrolytic solution such that the injection process time of the electrolytic solution is shortened, thereby improving the productivity of the rechargeable battery. 
         [0108]      FIG. 6  is an exploded perspective view of a rechargeable battery according to another exemplary embodiment of the present invention; and  FIG. 7  is a cross-sectional view of the rechargeable battery of  FIG. 6 , taken along the line VII-VII, illustrating a state in which a residual electrolytic solution is absorbed in an absorption member. 
         [0109]    Referring to  FIGS. 6 and 7 , a rechargeable battery  200  according to another exemplary embodiment of the present invention has a same configuration as the rechargeable battery  100  described above, except for an auxiliary absorption member  190 . 
         [0110]    Therefore, further description of the same components as those of the rechargeable battery  100  described above will not be repeated. 
         [0111]    The auxiliary absorption member  190  according to an exemplary embodiment of the present invention is coupled with a side of the case  25  within the case  25 . 
         [0112]    In one embodiment, as shown in  FIG. 7 , the auxiliary absorption member  190  is coupled with a first portion S2 of an inner side of the case  25  that is disposed above a first or upper surface S1 of the electrode assembly  10  facing the cap plate  20 . 
         [0113]    The electrolytic solution injected through the electrolyte injection port  21  may be filled up to the first surface S1 of the electrode assembly  10  within the case  25 . 
         [0114]    Therefore, the electrolytic solution is not absorbed in the auxiliary absorption member  190  coupled with the first portion S2 of the case  25  that is disposed above the first surface S1 of the electrode assembly  10  during the injection of the electrolytic solution. 
         [0115]    As illustrated in  FIG. 7 , when the case  25  is rotates clockwise or counterclockwise or inverted such that the cap plate  20  faces a gravity direction, or, in other words, a normal to the cap plate  20  pointing away from the case  25  is parallel to the direction of gravity, the residual electrolytic solution E remaining in the case  25  may be absorbed in the absorption member  90  and the auxiliary absorption member  190  disposed in the case  25 . 
         [0116]    When the case  25  is rotated clockwise or counterclockwise or inverted, the residual electrolytic solution E flows down along a side wall within the case  25 . 
         [0117]    Therefore, the residual electrolytic solution E is primarily absorbed in the auxiliary absorption member  190  coupled with the first portion S2 of the side wall within the case  25  and the residual electrolytic solution E that is not absorbed in the auxiliary absorption member  190  is absorbed in the absorption member  90 . 
         [0118]    Consequently, the residual electrolytic solution E within the case  25  may be quickly removed by the auxiliary absorption member  190  according to an exemplary embodiment of the present invention. 
         [0119]    Further, according to an exemplary embodiment of the present invention, a large amount of residual electrolytic solution E may be removed by the absorption member  90  and the auxiliary absorption member  190 . 
         [0120]    According to another embodiment of the present invention, the absorption member  90  may not be included in the rechargeable battery  200 . That is, the rechargeable battery  200 , in another embodiment, may include the auxiliary absorption member  190  coupled on an inner side wall of the case  25 , while not including the absorption member  90  coupled with a surface of the cap plate  20 . 
         [0121]    Therefore, according to an exemplary embodiment of the present invention, it is possible to prevent or substantially prevent a short circuit from occurring within the case  25  due to the residual electrolytic solution E, and the injection process time of the electrolytic solution may be shortened, thereby improving the productivity of the rechargeable battery. 
         [0122]      FIG. 8  is an exploded perspective view of a rechargeable battery according to another exemplary embodiment of the present invention;  FIG. 9  is a cross-sectional view of the rechargeable battery of  FIG. 8 , taken along the line IX-IX, illustrating a state in which a residual electrolytic solution is absorbed in an absorption member; and  FIG. 10  is a cross-sectional view of the rechargeable battery of  FIG. 8 , taken along the line X-X, illustrating a state in which a residual electrolytic solution is absorbed in an absorption member. 
         [0123]    Referring to  FIGS. 8 to 10 , a rechargeable battery  300  according to another exemplary embodiment of the present invention has a same configuration as the rechargeable battery  100  described above, except for an absorption member  290 . 
         [0124]    Therefore, further description of the same components as those of the rechargeable battery  100  described above will not be repeated. 
         [0125]    Referring to  FIG. 8 , the absorption member  290  according to an exemplary embodiment of the present invention includes a first groove  291 , a second groove  292 , a third groove  293 , a fourth groove  294 , a protruding part  295 , and a flat part  296 . In order to illustrate the shape of the absorption member  290 , the cap plate  20  together with the absorption member  290  is shown upside down in  FIG. 8 . Thus, for assembly of the rechargeable battery  300 , the upper side of the absorption member  290  as shown in  FIG. 8  becomes the lower side of the absorption member  290  facing the electrode assembly  10  after assembly. 
         [0126]    The first to fourth grooves  291 ,  292 ,  293 , and  294  according to an embodiment of the present invention may have a same configuration as the first to fourth grooves  91 ,  92 ,  93 , and  94  of the absorption member  90  described above, and, therefore, further detailed description of the first to fourth grooves  291 ,  292 ,  293 , and  294  and their coupling relationship with other components will be omitted. 
         [0127]    According to an exemplary embodiment of the present invention, the flat part  296  is provided with the first groove  291 , the second groove  292 , the third groove or electrolyte injection port groove  293 , and the fourth groove or vent hole groove  294 , and one surface of the flat part  296  is coupled with a surface of the cap plate  20  facing the inside of the case  25 . 
         [0128]    The protruding part  295  according to an exemplary embodiment of the present invention protrudes along an edge of the flat part  296 . 
         [0129]    In more detail, the protruding part  295  according to an exemplary embodiment of the present invention protrudes, forming a closed curve along an edge of the flat part  296 . 
         [0130]    In one embodiment, the protruding part  295  may protrude by forming an angle (e.g., a predetermined angle) with respect to the flat part  296 . 
         [0131]    According to an exemplary embodiment of the present invention, when the cap plate  20  is coupled with the opening of the case  25 , the protruding part  295  coupled with the cap plate  20  faces the inside of the case  25 . 
         [0132]    In this case, the absorption member  290  is disposed within the case  25  in the state in which the protruding part  295  contacts a part of a side wall within the case  25 . 
         [0133]    As illustrated in  FIGS. 9 and 10 , when the case  25  is rotated clockwise or counterclockwise or inverted such that the cap plate  20  faces a gravity direction, or, in other words, a normal of the cap plate  20  pointing away from the case  25  is parallel to the direction of gravity, the residual electrolytic solution E remaining in the case  25  may be absorbed in the absorption member  290  disposed in the case  25 . 
         [0134]    When the case  25  is rotated clockwise or counterclockwise or inverted, the residual electrolytic solution E flows down along the side wall within the case  25 . 
         [0135]    Therefore, the residual electrolytic solution E is primarily absorbed in the protruding part  295  of the absorption member  290  contacting the side wall within the case  25  and the residual electrolytic solution E that is not absorbed in the protruding part  295  is absorbed in the flat part  296  of the absorption member  290 . 
         [0136]    Consequently, according to an exemplary embodiment of the present invention, the residual electrolytic solution E flowing down along the side wall within the case  25  may be quickly removed by the protruding part  295  of the absorption member  290 . 
         [0137]    Further, according to an exemplary embodiment of the present invention, a large amount of residual electrolytic solution E may be removed by the protruding part  295  and the flat part  296  of the absorption member  290 . 
         [0138]    According to another embodiment of the present invention, the rechargeable battery  300  may further include the auxiliary absorption member  190  described above coupled on an inner side wall of the case  25 , while also including the absorption member  290  coupled with a surface of the cap plate  20 . 
         [0139]    Therefore, according to embodiments of the present invention, it is possible to prevent or substantially prevent a short circuit from occurring within the case  25  due to the residual electrolytic solution E, and the injection process time of the electrolytic solution may be shortened, thereby improving the productivity of the rechargeable battery. 
         [0140]    While the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, and equivalents thereof.