Patent Publication Number: US-2020295339-A1

Title: Secondary battery

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0027751, filed on Mar. 11, 2019 in the Korean Intellectual Property Office, the entire content of which is herein incorporated by reference. 
     BACKGROUND 
     1. Field 
     Aspects of embodiments of the present disclosure relate to a secondary battery. 
     2. Description of the Related Art 
     Unlike a primary battery that cannot be charged, a secondary battery can be charged and discharged. Low-capacity secondary batteries packaged in the form of a pack including a single battery cell may be used as the power source for various portable small-sized electronic devices, such as, for example, cellular phones or camcorders, while high-capacity secondary batteries having several tens to several hundreds of battery cells connected to one another may be used as a power source for motor drives, such as those in hybrid vehicles, electric vehicles, or the like. 
     The secondary battery may be configured by accommodating an electrode assembly including a positive electrode plate, a negative electrode plate, and a separator positioned therebetween, and an electrolyte in a case and installing a cap plate on the case. Representative examples of the electrode assembly may include a winding type electrode assembly and a stacking type electrode assembly. The electrode assembly may include uncoated portion tabs upwardly protruding and current collector members connected to the uncoated portion tabs. 
     The above information disclosed in this Background section is 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 
     According to an aspect of embodiments of the present disclosure, a secondary battery having a high capacity using a wound or stacked electrode assembly is provided. According to another aspect of embodiments of the present disclosure, a secondary battery capable of preventing or substantially preventing an electrode assembly from being damaged by a current collector member when an external force is horizontally applied is provided. According to another aspect of embodiments of the present disclosure, a secondary battery includes a current collector member and an uncoated portion tab connected and bent to be finished using an insulating tape member, thereby preventing or substantially preventing problems, such as, for example, an electrical short circuit, due to reverting of the current collector member and the uncoated portion tab, without reverting to their initial states in which they are yet to be bent. 
     These and other aspects and features of the present disclosure will be described in or will be apparent from the following description of some example embodiments of the present disclosure. 
     According to one or more embodiments of the present disclosure, a secondary battery includes: an electrode assembly including an uncoated portion tab, a current collector member connected to the uncoated portion tab and bent with the uncoated portion tab, and a tape member covering connected and bent regions of the uncoated portion tab and the current collector member. 
     The tape member may be attached to the uncoated portion tab or the current collector member. 
     The tape member may have a region attached to the uncoated portion tab or the current collector member and another region attached to the electrode assembly. 
     The tape member may have resistance to heat of at least 150° C. 
     The tape member may include polyimide, polyether ether ketone, liquid crystal polymer, or polyphenylene sulfide. 
     The current collector member may include a first section connected to a terminal portion, a second section bent from the first section to be in close contact with the electrode assembly, and a third section extending from the second section and connected to the uncoated portion tab. 
     The third section may be bent to be in close contact with the second section. 
     The third section may be connected to the second section or may extend from the second section. 
     The secondary battery may further include a retainer covering the tape member, the uncoated portion tab, and the current collector member. 
     The secondary battery may further include an insulation bag accommodating the electrode assembly and the retainer. 
     As described above, a secondary battery according to embodiments of the present disclosure employs a wound or stacked electrode assembly, wherein the uncoated portion tab faces a first direction (e.g., a horizontal direction), rather than a second direction (e.g., a vertical direction), thereby efficiently utilizing an internal space of a cell and increasing battery capacity. In addition, in a secondary battery according to embodiments of the present disclosure, since a current collector member is bent after being connected to an uncoated portion tab, an electrode assembly can be prevented or substantially prevented from being damaged when an external force is horizontally applied, thereby preventing or substantially preventing an electrical short circuit between the current collector member and the electrode assembly. Further, in a secondary battery according to embodiments of the present disclosure, after a current collector member and an uncoated portion tab are connected and bent together, the resulting structure is finished using an insulating tape member, thereby preventing or substantially preventing the bent current collector member and the bent uncoated portion tab from reverting to their initial states in which they are yet to be bent. Accordingly, it is possible to avoid problems, such as, for example, an electrical short circuit, due to reverting of the current collector member and the uncoated portion tab. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIGS. 1A, 1B, and 1C  are a perspective view, a cross-sectional view, and a partial perspective view of a secondary battery according to an embodiment of the present disclosure. 
         FIG. 2  is a flow diagram illustrating an assembling method of a secondary battery according to an embodiment of the present disclosure. 
         FIGS. 3A to 31  are perspective views illustrating a method of manufacturing a secondary battery according to an embodiment of the present disclosure. 
     
    
    
     DESCRIPTION OF REFERENCE NUMERALS 
       
     
       
         
           
               
               
             
               
                   
               
             
            
               
                 100: Secondary battery 
                 110: Electrode assembly 
               
               
                 111: First electrode plate 
                 112: Second electrode plate 
               
               
                 113: Separator 
                 114: First uncoated portion tab 
               
               
                 115: Second uncoated portion tab 
                 116: First region 
               
               
                 117A, 117B: Second region 
                 118A, 118B: Third region 
               
               
                 119A, 119B: Tape member 
                 119C, 119D: Retainer 
               
               
                 120: Case 
                 130: First terminal portion 
               
               
                 131: First terminal pillar 
                 132: First terminal plate 
               
               
                 133: First terminal upper insulation member 
                 134: First terminal seal gasket 
               
               
                 135: First terminal lower insulation member 
                 140: Second terminal portion 
               
               
                 141: Second terminal pillar 
                 142: Second terminal plate 
               
               
                 143: Second terminal upper insulation member 
                 144: Second terminal seal  
               
               
                 145: Second terminal lower insulation member 
                 gasket 
               
               
                 150: First current collector member 
                 151: First section 
               
               
                 152: Second section 
                 153: Third section 
               
               
                 160: Second current collector member 
                 161: First section 
               
               
                 162: Second section 
                 163: Third section 
               
               
                 170: Cap assembly 
                 171: Cap plate 
               
               
                 172: Electrolyte injection unit 
                 173: Seal plug 
               
               
                 174: Vent hole 
                 175: Vent plate 
               
               
                   
               
            
           
         
       
     
     DETAILED DESCRIPTION 
     Herein, some example embodiments of the present disclosure will be described in further detail. The subject matter of the present disclosure, however, may be embodied in many different forms and should not be construed as being limited to the example (or exemplary) embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be thorough and complete and will convey the aspects and features of the present disclosure to those skilled in the art. 
     In addition, in the accompanying drawings, sizes or thicknesses of various components may be exaggerated for brevity and clarity. Like numbers refer to like elements throughout. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. In addition, it is to be understood that when an element A is referred to as being “connected to” an element B, the element A may be directly connected to the element B or one or more intervening elements C may be present therebetween such that the element A and the element B are indirectly connected to each other. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of the disclosure. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is to be further understood that the terms “comprise” or “include” and/or “comprising” or “including,” when used in this specification, specify the presence of stated features, numbers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, and/or groups thereof. 
     It is to be understood that, although the terms “first,” “second,” etc. may be used herein to describe various members, elements, regions, layers, and/or sections, these members, elements, regions, layers, and/or sections should not be limited by these terms. These terms are used to distinguish one member, element, region, layer, and/or section from another. Thus, for example, a first member, a first element, a first region, a first layer, and/or a first section discussed below could be termed a second member, a second element, a second region, a second layer, and/or a second section without departing from the teachings of the present disclosure. 
     Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. It is to be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “on” or “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It is to be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     Referring to  FIGS. 1A, 1B, and 1C , a perspective view, a cross-sectional view, and a partial perspective view of a secondary battery according to an embodiment of the present disclosure are illustrated.  FIG. 1B  is a cross-sectional view taken along the line  1 B- 1 B of  FIG. 1A . 
     As shown in  FIGS. 1A, 1B, and 1C , a secondary battery  100  according to an embodiment of the present disclosure may include an electrode assembly  110 , a case  120  accommodating the electrode assembly  110 , a first terminal portion  130  electrically connected to a first side of the electrode assembly  110 , a second terminal portion  140  electrically connected to a second side of the electrode assembly  110 , a first current collector member  150  positioned between the first side of the electrode assembly  110  and the first terminal portion  130 , a second current collector member  160  positioned between the second side of the electrode assembly  110  and the second terminal portion  140 , and a cap assembly  170  coupled to an opening of the case  120 . 
     In some embodiments, the secondary battery  100  may further include first and second tape members  119 A and  119 B attached to the first side and the second side of the electrode assembly  110 , respectively. In some embodiments, the secondary battery  100  may further include first and second retainers  119 C and  119 D covering the first and second tape members  119 A and  119 B, respectively. In some embodiments, the secondary battery  100  may further include an insulation bag  190  covering the electrode assembly  110 . 
     The secondary battery  100  according to an embodiment of the present disclosure is a lithium ion secondary battery, which will be described by way of example with regard to a prismatic type, and the electrode assembly  110  will be described by way of example with regard to a prismatic type. However, embodiments of the present disclosure are not limited thereto, and, in an embodiment, the electrode assembly  110  may be a stacked electrode assembly. In addition, embodiments of the present disclosure may be applied to any of various types of batteries, including lithium polymer batteries, lithium solid batteries, and so on. 
     The electrode assembly  110  may include a first electrode plate  111 , a second electrode plate  112 , and a separator  113  positioned between the first and second electrode plates  111  and  112 . In some embodiments, the electrode assembly  110  may have a shape of a rectangular parallelepiped in which the first electrode plate  111 , the separator  113 , and the second electrode plate  112  are stacked in that order and then wound. For example, the electrode assembly  110  may be wound in a first direction (e.g., a horizontal direction). In addition, in some embodiments, the electrode assembly  110  may have a shape of a rectangular parallelepiped in which the first electrode plate  111 , the separator  113 , and the second electrode plate  112  are stacked in that order, but are not wound. In an embodiment, when the stacked electrode assembly  110  having the shape of a rectangular parallelepiped is coupled to the case  120  having an approximately parallelepiped opening, there may be little gap between the electrode assembly  110  and the case  120 , thereby considerably increasing battery capacity. 
     In an embodiment, the electrode assembly  110  may include a pair of first regions  116 , a pair of second regions  117 A and  1176  connecting the first regions  116 , and a pair of third regions  118 A and  1186  connecting the first regions  116  and the second regions  117 A and  1176 . The electrode assembly  110  may include one or more electrode assemblies. Here, an area occupied by the pair of first regions  116  may be larger than that occupied by the pair of second regions  117 A and  1176 . In addition, an area occupied by the pair of third regions  118 A and  118 B may be larger or smaller than that occupied by the pair of second regions  117 A and  1176 . 
     In an embodiment, the first electrode plate  111  may operate as a negative electrode, and the second electrode plate  112  may operate as a positive electrode. Conversely, the first electrode plate  111  may operate as a positive electrode, and the second electrode plate  112  may operate as a negative electrode. However, for brevity and clarity, the present disclosure will be described with regard to an example in which the first electrode plate  111  operates as a negative electrode and the second electrode plate  112  operates as a positive electrode. 
     The first electrode plate  111  may be formed by coating a first electrode active material, such as graphite or carbon, on a first electrode current collector formed of a metal foil made of copper, a copper alloy, nickel, or a nickel alloy, for example, and may include a first uncoated portion tab  114  on which the first electrode active material is not coated. The first uncoated portion tab  114  may function as a path for a flow of current between the first electrode plate  111  and the first terminal portion  130 . 
     In an embodiment, as shown in  FIG. 1C , the first uncoated portion tab  114  may protrude or extend by a length (e.g., a predetermined length) from a side of the electrode assembly  110  and may be bent in an approximately L-shaped configuration. With this configuration, the first uncoated portion tab  114  may be connected to the first current collector member  150 , which will be described later. In some embodiments, the first uncoated portion tab  114  of the electrode assembly  110  is planar in its original configuration, but may then be bent in the approximately L-shaped configuration after being connected to the first current collector member  150 . 
     The second electrode plate  112  may be formed by coating a second electrode active material, such as a transition metal oxide, on a second electrode current collector formed of a metal foil made of aluminum or an aluminum alloy, for example, and may include a second uncoated portion tab  115  on which the second electrode active material is not coated. The second uncoated portion tab  115  may function as a path for a flow of current between the second electrode plate  112  and the second terminal portion  140 . 
     In an embodiment, the second uncoated portion tab  115  may protrude or extend by a length (e.g., a predetermined length) from the second side of the electrode assembly  110  and may be bent in an approximately L-shaped configuration. With this configuration, the second uncoated portion tab  115  may be connected to the second current collector member  160 , which will be described later. In some embodiments, the second uncoated portion tab  115  of the electrode assembly  110  is planar in its original configuration, but may then be bent in the approximately L-shaped configuration after being connected to the second current collector member  160 . 
     In an embodiment, the first uncoated portion tab  114  and the second uncoated portion tab  115  may be configured such that they protrude and extend by a length (e.g., a predetermined length) from the electrode assembly  110  in horizontally opposite directions and are then bent. 
     The separator  113  may be positioned between the first electrode plate  111  and the second electrode plate  112  to prevent or substantially prevent an electrical short circuit and to allow for movement of lithium ions. In an embodiment, the separator  113  may be made of polyethylene, polypropylene, or a composite film of polyethylene and polypropylene. However, embodiments of the present disclosure are not limited to the above-described materials of the separator  113 . In some embodiments, the separator  113  may be replaced by a solid electrolyte. 
     The electrode assembly  110  may be received in the case  120  along with, for example, an electrolyte, but is not limited thereto. In an embodiment, the electrolyte may include a lithium salt, such as LiPF 6  and/or LiBF 4 , dissolved in an organic solvent, such as EC (ethylene carbonate), PC (propylene carbonate), DEC (diethyl carbonate), EMC (ethyl methyl carbonate), or DMC (dimethyl carbonate). In addition, the electrolyte may be in a liquid phase, a solid phase, or a gel phase. 
     In an embodiment, the case  120  may have a shape of an approximately rectangular parallelepiped having a hollow cavity with a top opening. Thus, the electrode assembly  110  may be inserted into the inside of the case  120  through the opening. 
     The first terminal portion  130  may be electrically connected to the first uncoated portion tab  114  of the electrode assembly  110  by the first current collector member  150 . In an embodiment, the first terminal portion  130  may include a first terminal pillar  131  penetrating a cap plate  171  of the cap assembly  170 , and the first current collector member  150  may be electrically connected to the first terminal pillar  131  in the case  120 . In addition, the first uncoated portion tab  114  of the electrode assembly  110  may be connected to the first current collector member  150 . 
     In an embodiment, the first current collector member  150  may be made of a same material as the first uncoated portion tab  114 . In some embodiments, the first uncoated portion tab  114  is made of a copper- or nickel-based material, and the first current collector member  150  may also be made of a copper- or nickel-based material. Therefore, the first uncoated portion tab  114  may be easily welded to the first current collector member  150 . 
     In some embodiments, the first current collector member  150  may be easily bendable. In some embodiments, since the first current collector member  150  is bent in approximately L- and/or U-shaped configurations in the course of manufacturing the secondary battery  100 , the first current collector member  150  may have ductility. 
     The second terminal portion  140  may be electrically connected to the second uncoated portion tab  115  of the electrode assembly  110  by the second current collector member  160 . In an embodiment, the second terminal portion  140  may include a second terminal pillar  141  penetrating the cap plate  171  of the cap assembly  170 , and the second current collector member  160  may be electrically connected to the second terminal pillar  141  in the case  120 . In addition, the second uncoated portion tab  115  of the electrode assembly  110  may be connected to the second current collector member  160 . 
     In an embodiment, the second current collector member  160  may be made of a same material as the second uncoated portion tab  115 . In some embodiments, the second uncoated portion tab  115  is made of an aluminum-based material, and the second current collector member  160  may also be made of an aluminum-based material. Therefore, the second uncoated portion tab  115  may be easily welded to the second current collector member  160 . 
     In some embodiments, the second current collector member  160  may be easily bendable. In some embodiments, since the second current collector member  160  is bent in approximately L- and/or U-shaped configurations in the course of manufacturing the secondary battery  100 , the second current collector member  160  may have ductility. 
     The cap assembly  170  may include the cap plate  171  in a shape of a planar panel. In some embodiments, the cap plate  171  may be formed of a thin panel and may be coupled to the opening of the case  120  to close the opening. In an embodiment, the cap plate  171  may include an electrolyte injection unit  172  for injecting an electrolyte into the closed case  120 . After the injection of the electrolyte, the electrolyte injection unit  172  may be closed by a seal plug  173 . In an embodiment, the cap plate  171  may include a vent hole  174  and a vent plate  175  installed in the vent hole  174  and configured to rupture when the internal pressure of the closed case  120  exceeds a certain pressure (e.g., a preset pressure). 
     In an embodiment, the first terminal portion  130  may be positioned on the cap plate  171  and may include a first terminal plate  132  (made of, for example, aluminum) coupled to the first terminal pillar  131 , a first terminal upper insulation member  133  installed between the first terminal plate  132  and the cap plate  171 , a first terminal seal gasket  134  positioned between the first terminal pillar  131  and the cap plate  171 , and a first terminal lower insulation member  135  installed between the first current collector member  150  connected to the first terminal pillar  131  and the cap plate  171 . 
     In an embodiment, the second terminal portion  140  may be positioned on the cap plate  171  and may include a second terminal plate  142  (made of, for example, aluminum) coupled to the second terminal pillar  141 , a second terminal upper insulation member  143  installed between the second terminal plate  142  and the cap plate  171 , a second terminal seal gasket  144  positioned between the second terminal pillar  141  and the cap plate  171 , and a second terminal lower insulation member  145  installed between the second current collector member  160  connected to the second terminal pillar  141  and the cap plate  171 . 
     In an embodiment, the second terminal upper insulation member  143  may be replaced by a high-resistance conductor. In this case, the cap plate  171  and the case  120  may have a same polarity as the second terminal portion  140 . In some embodiments, the secondary battery  100  may include the case  120  and the cap plate  171  having a positive polarity. 
     The first current collector member  150  may be positioned at a side of the electrode assembly  110  and may have a particular structure to be efficiently connected to the first uncoated portion tab  114 . In some embodiments, the first current collector member  150  may include a first section  151  extending to be substantially parallel with a length direction of the third region  118 A of the electrode assembly  110  and/or a length direction of the cap plate  171 , a second section  152  vertically bent from the first section  151  and extending to be substantially parallel with a length direction of the second region  117 A of the electrode assembly  110 , and a third section  153  extending from the second section  152  and bent toward the second region  117 A after being connected to the first uncoated portion tab  114 . 
     Here, the first section  151  may be coupled to the first terminal pillar  131 . In an embodiment, after the third section  153  is connected (e.g., welded) to the first uncoated portion tab  114 , the third section  153  and the first uncoated portion tab  114  may be bent together toward the second region  117 A in an approximately L-shaped configuration. In some embodiments, the first and second sections  151  and  152  may be integrally formed and the separately provided third section  153  may be connected to the second section  152 . In some embodiments, the first, second, and third sections  151 ,  152 , and  153  may be integrally formed together. 
     The first tape member  119 A may be attached to the first uncoated portion tab  114  connected to the third section  153  of the first current collector member  150  and then bent. In some embodiments, the first tape member  119 A may be attached to the first uncoated portion tab  114 . In some embodiments, a region of the first tape member  119 A may be attached to the first uncoated portion tab  114 , and other regions of the first tape member  119 A may be attached to the first regions  116  of the electrode assembly  110 . Therefore, the third section  153  and the first uncoated portion tab  114  may not revert to their initial states in which they are yet to be bent. In an embodiment, the first retainer  119 C having an insulating property may cover the first uncoated portion tab  114 , the first tape member  119 A, and the second region  117 A. 
     The second current collector member  160  may be positioned at the other side of the electrode assembly  110  and may have a particular structure to be efficiently connected to the second uncoated portion tab  115 . In some embodiments, the second current collector member  160  may include a first section  161  extending to be substantially parallel with the length direction of the third region  118 A of the electrode assembly  110  and/or the length direction of the cap plate  171 , a second section  162  vertically bent from the first section  161  and extending to be substantially parallel with the length direction of the second region  1176  of the electrode assembly  110 , and a third section  163  extending from the second section  162  and bent toward the second region  1176  after being connected to the second uncoated portion tab  115 . 
     Here, the first section  161  may be coupled to the second terminal pillar  141 . In an embodiment, after the third section  163  is connected (e.g., welded) to the second uncoated portion tab  115 , the third section  163  and the second uncoated portion tab  115  may be bent together toward the second region  1176  in an approximately L-shaped configuration. In some embodiments, the first and second sections  161  and  162  may be integrally formed and the separately provided third section  163  may be connected to the second section  162 . In some embodiments, the first, second, and third sections  161 ,  162 , and  163  may be integrally formed together. 
     The second tape member  1196  may be attached to the second uncoated portion tab  115  connected to the third section  163  of the second current collector member  160  and then bent. In some embodiments, the second tape member  119 B may be attached to the second uncoated portion tab  115 . In some embodiments, a region of the second tape member  1196  may be attached to the second uncoated portion tab  115 , and other regions of the second tape member  1196  may be attached to the first regions  116  of the electrode assembly  110 . Therefore, the third section  163  and the second uncoated portion tab  115  may not revert to their initial states in which they are yet to be bent. In an embodiment, the second retainer  119 D having an insulating property may cover the second uncoated portion tab  115 , the second tape member  1196 , and the second region  117 B. 
     The first and second tape members  119 A and  1196  may be resistant to heat higher than approximately 150° C., and, in an embodiment, approximately 200° C., and, in an embodiment, approximately 250° C. In some examples, the melting points of the first and second tape members  119 A and  119 B may be approximately 150° C., preferably approximately 200° C., more preferably approximately 250° C. or more. Therefore, even while the secondary battery  100  operates at high temperature, the first and second tape members  119 A and  1196  may not be melted and the uncoated portion tabs  114  and  115  and the current collector members  150  and  160  connected thereto may be maintained at bent states. In some embodiments, the first and second tape members  119 A and  119 B may include, but are not limited to, polyimide, polyether ether ketone, liquid crystal polymer, or polyphenylene sulfide. 
     The insulation bag  180  may receive the electrode assembly  110  and the first and second retainers  119 C and  119 D. In some embodiments, the insulation bag  180  may be positioned between each of the electrode assembly  110 , the first and second retainers  119 C and  119 D, and the case  120 . Therefore, the insulation bag  180  may prevent or substantially prevent an electrical short circuit between the electrode assembly  110  and the case  120 . 
       FIG. 2  is a flow diagram illustrating an assembling method of a secondary battery according to an embodiment of the present disclosure. 
     As shown in  FIG. 2 , an assembling method of the secondary battery  100  according to an embodiment of the present disclosure may include an electrode assembly preparing or providing (S 1 ), an uncoated portion tab notching (S 2 ), an uncoated portion tab preliminary welding (S 3 ), an uncoated portion tab cutting (S 4 ), a current collector member welding (S 5 ), an uncoated portion tab and current collector member bending (S 6 ), a retainer providing (S 7 ), an insulation bag providing (S 8 ), a case providing (S 9 ), and a cap assembly and case welding (S 10 ). 
       FIGS. 3A to 31  are perspective views illustrating a method of manufacturing a secondary battery  100  according to an embodiment of the present disclosure. Here, a wound electrode assembly  110 , by way of example, will be described with reference to  FIGS. 3A to 31  together with  FIG. 2 , but a stacked electrode assembly may also be applied to embodiments of the present disclosure. 
     As shown in  FIG. 3A , in the electrode assembly preparing or providing (S 1 ), one or more electrode assemblies  110 , each wound approximately in a first direction (e.g., a horizontal direction), may be prepared or provided. 
     In some embodiments, a first uncoated portion  114 A may protrude or extend to one side of the first direction, and a second uncoated portion  115 A may protrude or extend to the other side of the first direction. In some embodiments, the electrode assembly  110  may include a pair of first regions  116  facing each other (only a front surface is shown in the drawing), a pair of second regions  117 A and  117 B connecting the pair of first regions  116  and facing each other, and a pair of third regions  118 A and  118 B connecting the pair of first regions  116  and the pair of second regions  117 A and  117 B. In some embodiments, lengths (e.g., heights) of the first and second uncoated portions  114 A and  115 A may be equal to those (e.g., heights) of the second regions  117 A and  117 B. 
     As shown in  FIG. 3B , in an embodiment, in the uncoated portion tab notching (S 2 ), regions other than some regions of the first and second uncoated portions  114 A and  115 A may be removed. 
     In some embodiments, notching may be performed by laser or pressing. 
     Accordingly, the first and second uncoated portion tabs  114  and  115  protruding or extending from the second regions  117 A and  117 B may remain, respectively. 
     In some embodiments, the first and second uncoated portion tabs  114  and  115  may be located at upper regions of the second regions  117 A and  1176 , respectively. In some embodiments, the first and second uncoated portion tabs  114  and  115  may be generally located at central or lower regions of the second regions  117 A and  1176 , respectively. In addition, in some embodiments, as a result of the notching, the lengths (e.g., heights) of the first and second uncoated portion tabs  114  and  115  may be smaller than those (e.g., heights) of the second regions  117 A and  117 B. 
     As shown in  FIG. 3C , in the uncoated portion tab preliminary welding (S 3 ), the first and second uncoated portion tabs  114  and  115  may be preliminarily welded (W 1  and W 2 ) to be connected to each other. 
     The preliminary welding (W 1  and W 2 ) may reduce thicknesses of the first and second uncoated portion tabs  114  and  115 . For example, the first and second uncoated portion tabs  114  and  115  may be spaced apart from each other. However, as a result of the preliminary welding (W 1  and W 2 ), the first and second uncoated portion tabs  114  and  115  may be brought into close contact with each other to then be electrically connected to each other, thereby reducing the thicknesses of the first and second uncoated portion tabs  114  and  115 . 
     As shown in  FIG. 3D , in the uncoated portion tab cutting (S 4 ), some regions of the first and second uncoated portion tabs  114  and  115  may be cut to be removed. 
     In some embodiments, the cutting may be performed by laser or pressing. 
     Accordingly, widths of the first and second uncoated portion tabs  114  and  115  may be further reduced. In an embodiment, since volumes occupied by the first and second uncoated portion tabs  114  and  115  in the case  120  are reduced by the notching and cutting steps, the electrode assembly  110  having a further increased capacity may be accommodated in the case  120 . 
     As shown in  FIG. 3E , in the current collector member welding (S 5 ), the first and second current collector portions  150  and  160  may be electrically welded to the first and second uncoated portion tabs  114  and  115 , respectively. Here, reference is also made to  FIGS. 1B and 1C  together. 
     In some embodiments, the cap assembly  170  may be prepared, the cap assembly  170  having the first and second terminal portions  130  and  140  coupled to the cap plate  171  and the first and second current collector portions  150  and  160  electrically connected to the first and second terminal portions  130  and  140 , and the first and second current collector portions  150  and  160  in the cap assembly  170  may be welded to the first and second uncoated portion tabs  114  and  115 , respectively. In an embodiment, laser welding, ultrasonic welding, or electrical resistance welding may be employed. 
     In some embodiments, the first current collector member  150  may include a first section  151  (see  FIG. 1B ) connected to the first terminal portion  130 , a second section  152  bent from the first section  151  and brought into close contact with the second region  117 A of the electrode assembly  110 , and a pair of third sections  153  (see  FIG. 1B ) bent from opposite sides of the second section  152  and outwardly extending. In some embodiments, a front one of the third sections  153  may be welded (W 3 ) to the first uncoated portion tab  114  of the front electrode assembly  110 , and a rear one of the third sections  153  may be welded (W 3 ) to the first uncoated portion tab  114  of the rear electrode assembly  110 . 
     In some embodiments, the first uncoated portion tabs  114  of the front electrode assembly  110  and the rear electrode assembly  110  may be welded (W 3 ) to the outer surfaces in the pair of third sections  153 , respectively. In other words, the first uncoated portion tabs  114  may be connected to the outer surfaces of the third sections  153 . 
     In addition, in some embodiments, the first uncoated portion tabs  114  of the front electrode assembly  110  and the rear electrode assembly  110  may be welded (W 3 ) to the inner surfaces in the pair of third sections  153 , respectively. In other words, the first uncoated portion tab  114  may be connected to the inner surfaces of the third sections  153 . In an embodiment, a region of the second section  152  of the first current collector member  150  may be removed so as to prevent or substantially prevent the region from interfering or overlapping with the first uncoated portion tab  114  of the electrode assembly  110 . 
     In some embodiments, the second current collector member  160  may include a first section  161  (see  FIG. 1B ) connected to the second terminal portion  140 , a second section  162  bent from the first section  161  and brought into close contact with the second region  117 B of the electrode assembly  110 , and a pair of third sections  163  (see  FIG. 1B ) bent from opposite sides of the second section  162  and outwardly extending. In some embodiments, a front one of the third sections  163  may be welded (W 4 ) to the second uncoated portion tab  115  of the front electrode assembly  110 , and a rear one of the third sections  163  may be welded (W 4 ) to the second uncoated portion tab  115  of the rear electrode assembly  110 . 
     In some embodiments, the second uncoated portion tabs  115  of the front electrode assembly  110  and the rear electrode assembly  110  may be welded (W 4 ) to the outer surfaces in the pair of third sections  163 , respectively. In other words, the second uncoated portion tabs  115  may be connected to the outer surfaces of the third sections  163 . 
     In some embodiments, the second uncoated portion tabs  115  of the front electrode assembly  110  and the rear electrode assembly  110  may be welded (W 4 ) to the inner surfaces in the pair of third sections  163 , respectively. In other words, the second uncoated portion tabs  115  may be connected to the inner surfaces of the third sections  163 . In an embodiment, a region of the second section  162  of the second current collector member  160  may be removed so as to prevent or substantially prevent the region from interfering or overlapping with the second uncoated portion tab  115  of the electrode assembly  110 . 
     In such a way, the third section  153  of the first current collector member  150  and the first uncoated portion tab  114  of the electrode assembly  110  welded thereto, may be provided, and the third section  163  of the second current collector member  160  and the second uncoated portion tab  115  of the electrode assembly  110  welded thereto, may be provided. Here, the third section  153  and the first uncoated portion tab  114  may be configured to outwardly protrude and extend from the second region  117 A of the electrode assembly  110 . In addition, the third section  163  and the second uncoated portion tab  115  may be configured to outwardly protrude and extend from the second region  1176  of the electrode assembly  110 . 
     As shown in  FIG. 3F , in the uncoated portion tab and current collector member bending (S 6 ), the uncoated portion tabs  114  and  115  and the current collector members  150  and  160  may be bent together to then be brought into close contact with the second regions  117 A and  1176  of the electrode assembly  110 , respectively. 
     In some embodiments, the first uncoated portion tab  114  and the third section  153  of the first current collector member  150  may be bent together to then be brought into close contact with the second region  117 A of the electrode assembly  110 , and, in an embodiment, with the second section  152  of the first current collector member  150 . In some embodiments, the third section  153  of the first current collector member  150  may be directly brought into close contact with the second section  152 . Accordingly, in an embodiment, the first uncoated portion tab  114  may be exposed at an outermost portion. 
     In some embodiments, when the first uncoated portion tab  114  is connected to the interior of the third section  153 , the first uncoated portion tab  114  may be directly brought into close contact with the second region  117 A of the electrode assembly  110 . Accordingly, in an embodiment, the third section  153  may be exposed at an outermost portion. 
     In some embodiments, the second uncoated portion tab  115  and the third section  163  of the second current collector member  160  may be bent together to then be brought into close contact with the second region  1176  of the electrode assembly  110 , and, in an embodiment, with the second section  162  of the second current collector member  160 . In some embodiments, the third section  163  of the second current collector member  160  may be directly brought into close contact with the second section  162 . Accordingly, in an embodiment, the second uncoated portion tab  115  may be exposed at an outermost portion. 
     In some embodiments, when the second uncoated portion tab  115  is connected to the interior of the third section  163 , the second uncoated portion tab  115  may be directly brought into close contact with the second region  1176  of the electrode assembly  110 . Accordingly, in an embodiment, the third section  163  may be exposed to the outermost portion. 
     The tape members  119 A and  1196  may be attached to prevent or substantially prevent the uncoated portion tabs  114  and  115  and the current collector members  150  and  160  from reverting to their initial states after the uncoated portion tabs  114  and  115  and the current collector members  150  and  160  are bent. 
     In some embodiments, the first tape member  119 A may be adhered to the first uncoated portion tab  114  bent in the approximately L-shaped configuration. In addition, in some embodiments, a first side region of the first tape member  119 A may be adhered to the bent first uncoated portion tab  114 , and a second side region of the first tape member  119 A may be adhered to the first region  116  of the electrode assembly  110 . In some embodiments, the first tape member  119 A may be adhered to the first uncoated portion tab  114  and the pair of first regions  116  (only a front one of the pair of first regions is shown in the drawing) provided in the electrode assembly  110  in an approximately U-shaped configuration. 
     In some embodiments, when the third section  153  of the first current collector member  150  is exposed at an outermost portion, the first side region of the first tape member  119 A may be directly adhered to the third section  153 , and the second side region of the first tape member  119 A may be adhered to the first region  116  of the electrode assembly  110 . 
     In addition, in some embodiments, the second tape member  119 B may be adhered to the bent second uncoated portion tab  115 . In addition, in some embodiments, a first side region of the second tape member  1196  may be adhered to the bent second uncoated portion tab  115  and a second side region of the second tape member  1196  may be adhered to the first region  116  of the electrode assembly  110 . In some embodiments, the second tape member  1196  may be adhered to the second uncoated portion tab  115  and the pair of first regions  116  (only the front one of the pair of first regions is shown in the drawing) provided in the electrode assembly  110  in an approximately U-shaped configuration. 
     In some embodiments, when the third section  163  of the second current collector member  160  is exposed at an outermost portion, the first side region of the second tape member  1196  may be directly adhered to the third section  163 , and the second side region of the second tape member  1196  may be adhered to the first region  116  of the electrode assembly  110 . 
     In such a way, the bent uncoated portion tabs  114  and  115  and the bent current collector members  150  and  160  may be constrained in their bent states by the tape members  119 A and  1196  without reverting to their original states, thereby preventing or substantially preventing faults from being generated due to bending of the uncoated portion tabs  114  and  115  and the current collector members  150  and  160 . 
     Of course, it will be appreciated by a person skilled in the art that, in some embodiments, various insulation members, other than the first and second tape members  119 A and  119 B, can be adhered to the second regions  117 A and  117 B, the first regions  116 , and/or the third regions  118 A and  1186  of the electrode assembly  110 . 
     As shown in  FIG. 3G , in the retainer providing (S 7 ), insulating retainers  119 C and  119 D may be attached approximately to the second regions  117 A and  1176  of the electrode assembly  110 . 
     In some embodiments, the first retainer  119 C may be attached to the bent first uncoated portion tab  114 , the third section  153  of the bent first current collector member  150 , the first tape member  119 A, and the second region  117 A of the electrode assembly  110 . In addition, in some embodiments, the second retainer  119 D may be attached to the bent second uncoated portion tab  115 , the third section  163  of the second current collector member  160 , the second tape member  1196 , and the second region  117 B of the electrode assembly  110 . The first and second retainers  119 C and  119 D may prevent or substantially prevent the second regions  117 A and  1176  of the electrode assembly  110 , which face away from each other, from directly colliding with or contacting sidewalls of the case  120 . 
     As shown in  FIG. 3H , in the insulation bag providing (S 8 ), the electrode assembly  110  having the aforementioned configuration may be accommodated in the insulation bag  190 . 
     In some embodiments, the second regions  117 A and  1176  of the electrode assembly  110 , which face away from each other, and structures located around the electrode assembly  110 , the first regions  116  of the electrode assembly  110 , which face away from each other, and the third region  118 B of the electrode assembly  110 , may be accommodated in the insulation bag  190 . Accordingly, the electrode assembly  110 , the structures located around the electrode assembly  110 , and the case  120 , may be electrically insulated from one another. 
     As shown in  FIG. 3I , in the case providing (S 9 ), the electrode assembly  110  covered by the insulation bag  190  may be coupled to or inserted into the case  120  having an approximately parallelepiped top opening. 
     In the cap assembly and case welding (S 10 ), a periphery of the cap assembly  170  may be welded to the case  120 , thereby integrally forming the cap assembly  170  and the case  120  in mechanical/physical/electrical manners. 
     In some embodiments, the periphery of the cap plate  171  may be welded to the case  120 . The welding may be performed by, for example, but not limited to, laser beams. Accordingly, when the cap assembly  170  is charged with, for example, positive polarity, the case  120  may also be charged with positive polarity. In some embodiments, after the welding, an electrolyte may be injected through an injection hole. Of course, after the injecting, the injection hole may be closed by a seal plug  173 . 
     As described above, according to embodiments of the present disclosure, the wound or stacked electrode assembly may be used, and uncoated portion tabs may be located at second regions opposite to each other in a first direction (e.g., a horizontal direction), thereby efficiently utilizing an internal space of a cell and thereby increasing battery capacity. 
     In addition, according to embodiments of the present disclosure, since current collector members are connected to the uncoated portion tabs and then folded to the second regions, the electrode assembly may not be damaged by the current collector members even when an external force is horizontally applied, thereby preventing or substantially preventing electrical short circuits between the current collector members and the electrode assembly. 
     In addition, according to embodiments of the present disclosure, since insulating tape members are further adhered to the bent current collector members and the bent uncoated portion tabs, the bent current collector members and the bent uncoated portion tabs may be firmly brought into close contact with the second regions of the electrode assembly without reverting to their initial states in which they are yet to be bent. Accordingly, problems, such as, for example, an electrical short circuit, encountered by the bent current collector members and the bent uncoated portion tabs in the course of manufacturing or using batteries, may be prevented or substantially prevented. 
     While some example embodiments have been described to practice the secondary battery of the present disclosure, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as set forth by the following claims.