Abstract:
An electrode assembly and a lithium secondary battery comprising the same are disclosed. 
     Specifically, the present invention provides an electrode assembly which is capable of preventing the occurrence of a short circuit between a non-coating portion of an electrode plate and an active material layer of an electrode plate having an opposite polarity when damage or shrinkage of a separator takes place, through the attachment of an insulating tape to either or both sides of the non-coating portion of an electrode plate without attachment of an electrode tab. 
     Therefore, an internal short circuit of the battery can be prevented by application of the electrode assembly of the present invention to a variety of lithium secondary batteries including pouch-type, polygonal and cylindrical batteries.

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/074,566, entitled Electrode Assembly and Lithium Secondary Battery With the Same, filed Jun. 20, 2008 and hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a secondary battery. More specifically, the present invention relates to an electrode assembly and a lithium secondary battery comprising the same. 
     2. Description of the Related Art 
     Generally, the lithium secondary battery employs lithium-based oxide as a positive electrode active material and a carbon material as a negative electrode active material. Further, the lithium secondary batteries may be broadly classified into a liquid electrolyte battery and a polymer electrolyte battery, depending on the type of electrolytes used in them. The lithium battery using a liquid electrolyte is known as a lithium ion battery, and the lithium battery using a polymer electrolyte is known as a lithium polymer battery. In addition, the lithium secondary battery may be formed in various shapes, and the typical shape is a cylindrical shape, a polygonal shape or a pouch shape. 
     An electrode assembly is seated inside a case of such a lithium secondary battery. The electrode assembly is formed by stacking or winding a positive electrode plate, a negative electrode plate and a separator disposed therebetween. An electrode plate including the positive electrode plate and the negative electrode plate is composed of a current collector and an active material layer applied to at least one surface of the current collector. Both ends of the current collector are often provided with non-coating portions which are not coated with the active material layer. An electrode tab is provided on either one of the non-coating portions. 
     An insulating tape is attached to the boundary between the active material layer and the non-coating portion with formation of the electrode tab. The insulating tape protects an electrical connection part between the electrode plate and the electrode tab and prevents the occurrence of a short circuit due to direct contact between different electrode plates of opposite polarities. 
     Unfortunately, even though an insulating tape is provided on an electrode tab-fixed region in the non-coating portions formed on both ends of the electrode plate, an internal short circuit may occur due to non-coating portion/non coating portion contact or non-coating portion/active material layer contact between electrode plates of opposite polarities, when damage or shrinkage of a separator occurs due to internal or external impact or heat generation. 
     Further, the non-coating portion without provision of the electrode tab is more highly susceptible to the occurrence of an internal short circuit, due to probable contact with the non-coating portion or active material layer of the electrode plate having an opposite polarity. Particularly when the non-coating portion of the electrode plate is in contact with the active material layer of the electrode plate having an opposite polarity, it may cause fatal damage to thereby result in the danger of ignition or explosion of the battery. 
     SUMMARY OF THE INVENTION 
     Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to prevent the occurrence of an internal short circuit via the prevention of exposure of a non coating portion by insulating the non-coating portion of an electrode plate to which an electrode tab was not attached. 
     It is another object of the present invention to prevent the risk of an internal short circuit which may occur upon contact of a non-coating portion with an active material layer of a negative electrode plate, through the insulation of the non-coating portion with no formation of an electrode tab particularly in a positive electrode plate. 
     In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of an electrode assembly which is capable of preventing the occurrence of a short circuit between a non-coating portion of an electrode plate and an active material layer of an electrode plate having an opposite polarity when damage or shrinkage of a separator takes place, through the attachment of an insulating member to at least one side of the non-coating portion of an electrode plate without attachment of an electrode tab. 
     In accordance with another aspect of the present invention, there is provided an electrode assembly which is capable of achieving good heat dissipation efficiency by installation of an electrode tab in a non-coating portion of an electrode plate positioned on the outer periphery of an electrode assembly, and insulation of a non-coating portion of an electrode plate from an active material layer of an opposite polarity by installation of an insulating member in a non-coating portion of an electrode plate without formation of an electrode tab positioned on the inner periphery of an electrode assembly. 
     More specifically, a positive electrode tab of a positive electrode plate is installed in a rear positive electrode non-coating portion positioned on the outer periphery of the electrode assembly and a negative electrode tab of a negative electrode plate is installed in a rear negative electrode non-coating portion positioned on the outer periphery of the electrode assembly. Insulation between an electrode non-coating portion and an active material layer is achieved by attaching an insulating member to a front positive electrode non-coating portion of the positive electrode plate or a negative electrode active material layer of the corresponding negative electrode plate. 
     Preferably, desired insulating effects are obtained by attaching an insulating member to both sides of the front positive electrode non-coating portion of the positive electrode plate. 
     Where the insulating member is attached to the front positive electrode non-coating portion of the positive electrode plate or the negative electrode active material layer of the negative electrode plate oppositely corresponding to the front positive electrode non-coating portion, the insulating member is not necessarily attached to a front negative electrode non-coating portion of the negative electrode plate. 
     As a consequence, the front non-coating portion of the positive electrode plate with no attachment of the electrode tab, positioned on the inner periphery of the electrode assembly, will be insulated from the negative electrode active material layer of the negative electrode plate, even when damage or shrinkage of a separator takes place. Therefore, safety of the battery is improved by preventing the occurrence of a short circuit due to internal heat generation of a lithium secondary battery which is sought for the realization of higher capacity. 
     In one aspect the present invention comprises a battery assembly comprising a casing and an electrode assembly positioned within the casing, wherein the electrode assembly includes a first electrode, a second electrode and a separator interposed therebetween wherein the first electrode includes a first coated portion that is coated with a first electrode active material and at least one fit uncoated portion and wherein the second electrode includes a second coated portion that is coated with a second electrode active material and at least one second uncoated portion wherein the first and second uncoated portions have a length. In this aspect the invention further comprises a first electrode tab that is coupled to the at least one first uncoated portion of the first electrode and a second electrode tab that is coupled to the at least one second uncoated portion of the second electrode; and at least one lamination layer positioned on at least a part of the uncoated portions of the first and second electrodes so that at least one of the first and second uncoated portions are covered by the at least one lamination layer along their length. 
     In another aspect, the invention comprises an electrode assembly for a battery assembly, the electrode assembly comprising a first electrode having a first coated portion coated with a first electrode active material and a front and rear uncoated portions, a second electrode having a second coated portion coated with a second electrode active material and a front and rear uncoated portions and a separator interposed between the first and second electrodes. In this aspect; the invention further comprises a first electrode tab that is coupled to the rear uncoated portion of the first electrode a second electrode tab that is coupled to the rear uncoated portion of the second electrode and at least one lamination layer positioned on the front uncoated portions of at least one of the first and second electrodes so as to cover all of the at least one of the first and second electrodes. 
     In yet another aspect the invention comprises a method of forming an electrode assembly for a battery, the method comprising coating a portion of a first electrode with a first electrode coating material so as to define a coated portion and at least one non-coated portion having a length, coating a portion of the second electrode with a second electrode coating material so as to define a coated portion and at least one non-coated portion having a length and positioning at least one layer of lamination between the at least one non-coated portions of the first and second electrodes so that the at least one layer of lamination covers along the length of at least one of the non-coated portions of the first and second electrodes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an electrode assembly in accordance with one embodiment of the present invention; 
         FIG. 2A  is a cross-sectional view of  FIG. 1 ; 
         FIG. 2B  is an enlarged view of Part  2 B in  FIG. 2A ; 
         FIG. 2C  is a perspective view of Part  2 C in  FIG. 2B ; 
         FIG. 3  is a cutting process view of a front positive electrode non-coating portion of an electrode assembly in accordance with one embodiment of the present invention; 
         FIG. 4  is a cutting process view of a front positive electrode non-coating portion of an electrode assembly using a different method than that of  FIG. 3 ; 
         FIG. 5A  is a cross-sectional view of an electrode assembly in accordance with another embodiment of the present invention; 
         FIG. 5B  is an enlarged view of Part  5 B in  FIG. 5A ; 
         FIG. 6A  is a cross-sectional view of an electrode assembly in accordance with a further embodiment of the present invention; 
         FIG. 6B  is an enlarged view of Part  6 B in  FIG. 6A ; 
         FIG. 7A  is an exploded perspective view of a pouch-type lithium secondary battery using an electrode assembly in accordance with one embodiment of the present invention; 
         FIG. 7B  is a sectional view showing an assembly state of  FIG. 7A ; 
         FIG. 8  is an exploded perspective view of a polygonal-type lithium secondary battery using an electrode assembly in accordance with one embodiment of the present invention; and 
         FIG. 9  is an exploded perspective view of a cylinder-type lithium secondary battery using an electrode assembly in accordance with one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Now, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. 
     Referring to  FIG. 1  and  FIGS. 2A to 2C , an electrode assembly  100  in accordance with an embodiment of the present invention includes a positive electrode plate  110 , a negative electrode plate  120  and a separator  130 . The electrode assembly  100  is prepared by stacking the positive electrode plate  110 , the negative electrode plate  120  and the separator  130  disposed therebetween and winding the resulting stacked structure into a jelly roll shape. 
     In fabrication of the electrode assembly  100 , both ends of each of the positive electrode plate  110  and negative electrode plate  120  are provided with non-coating portions  113 ,  123  when the positive electrode plate  110 , the separator  130  and the negative electrode plate  120  are wound into a jelly-roll configuration. Among the non-coating portions  113 ,  123 , the non-coating portion where the winding starts is designated front non-coating portions  113 A,  123 A, whereas the non-coating portion where the winding ends is designated rear non-coating portions  113 B,  123 B. 
     For brevity and convenience of explanation, an inner periphery of the electrode assembly is defined as the portion where front ends of the wound positive electrode plate  110  and negative electrode plate  120  are positioned, whereas an outer periphery of the electrode assembly is defined as the portion where rear ends of the positive and negative electrode plates are positioned. In addition, out of both sides of the non-coating portion, one side facing toward the inner periphery of the electrode assembly is designated a front surface, whereas the other side facing toward the outer periphery of the electrode assembly is designated a rear surface. 
     In connection with the positive electrode non-coating portion  113 , the front positive electrode non-coating portion  113 A will be described with reference to two separate non-coating portions, i.e. a first front positive electrode non-coating portion  113 AA corresponding to the front surface and a second front positive electrode non-coating portion  113 AB corresponding to the rear surface. 
     In the positive electrode plate  110 , a positive electrode tab  140  is welded to a rear positive electrode non-coating portion  113 B. In the rear positive electrode non-coating portion  113 B, a protective tape  160  is attached to the portion to which the positive electrode tab  140  was welded. The protective tape  160  is attached to enclose the portion where the positive electrode tab  140  protrudes relative to the positive electrode current collector  111 . 
     A lamination tape  170 , such as a polyethylene or polypropylene, is attached to the front positive non-coating portion  113 A of the positive electrode plate  110 . The front positive non-coating portion has a length and the lamination tape is positioned to coat the uncoated portion along its length so as to substantially cover the non-coated portion. When the lamination tape  170  is attached to the front positive electrode non-coating portion  113 A of the positive electrode plate  110 , external exposure of the front positive electrode non-coating portion  113 A is avoided by such a lamination tape  170 . 
     More specifically, a first lamination tape  170 A is attached to a first front positive electrode non-coating portion  113 AA of the front positive electrode non-coating portion  113 A, whereas a second lamination tape  170 B is attached to a second front positive electrode non-coating portion  113 AB of the front positive electrode non-coating portion  113 A in the same manner as discussed above. 
     Therefore, the occurrence of a short circuit is inhibited because the first front positive electrode non-coating portion  113 AA of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  and the negative electrode active material layer  122 A of the corresponding negative electrode plate  120  are insulated from each other by the first lamination tape  170 A even when damage or shrinkage of the separators  130 ,  130 ′ occurs due to internal heat generation of the battery. Further, since a second front positive electrode non-coating portion  113 AB of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  is insulated from the negative electrode active material layer  122 B of the corresponding negative electrode plate  120  by a second lamination tape  170 B, the likelihood of occurrence of a short circuit is reduced. 
     The positive electrode plate  110  includes a positive electrode current collector  111  made of thin aluminum foil and a positive electrode active material layer  112  containing, as a main ingredient lithium-based oxide coated on both sides of the positive electrode current collector  111 . On the positive electrode current collector  111 , a positive electrode non-coating portion  113 , corresponding to the region which was not coated with the positive electrode active material layer  112 , is provided on both ends of the positive electrode plate  110 , thereby forming the front non-coating portion  113 A and the rear non-coating portion  113 B as described above. 
     Further, a positive electrode tab  140  is fixed to the non-coating portion of either one of the positive electrode non-coating portions  113  by ultrasonic welding. In one embodiment of the present invention, the positive electrode tab  140  is welded to the rear positive electrode non-coating portion  113 B of the positive electrode plate  110 . The positive electrode tab  140  is welded to protrude above an upper end of the positive electrode current collector  111 . The positive electrode tab  140  is conventionally formed of nickel or nickel alloy. Other metal materials may also be used for the positive electrode tab  140 . 
     A negative electrode tab  150  is welded to a rear negative electrode non-coating portion  123 B of the negative electrode plate  120 . A protective tape  160  is attached to the region of the rear negative electrode non-coating portion  123 B to which the negative electrode tab  150  was welded. The protective tape  160  is attached to enclose the portion where the negative electrode tab  150  protrudes relative to the negative electrode current collector  121 . 
     The negative electrode plate  120  includes a negative electrode current collector  121  made of thin copper foil and a negative electrode active material layer  122  containing, as a main ingredient, a carbon material coated on both sides of the negative electrode current collector  121 . For the negative electrode current collector  121 , a negative electrode non-coating portion  123 , corresponding to the region which was not coated with the negative electrode active material layer  122 , is also provided on both ends of the negative electrode plate. As described above, the negative electrode non-coating portion  123  is composed of a front negative electrode non-coating portion  123 A and a rear negative electrode non-coating portion  123 B. 
     A negative electrode tab  150  is fixed to the rear negative electrode non-coating portion  123 B of the negative electrode non-coating portion  123  by ultrasonic welding. Herein, the negative electrode tab  150  is welded to protrude above an upper part of the negative electrode current collector  121 . The negative electrode tab  150  is conventionally formed of nickel or nickel alloy. Other metals may also be used as a material for the negative electrode tab  150 . 
     The separator  130  is disposed between electrode plates  110 ,  120  so as to electrically isolate the positive electrode plate  110  from the negative electrode plate  120 . The separator  130  is formed of polyethylene, polypropylene, or a polyethylene/polypropylene composite film. The separator  130  is formed to have a width larger than that of the positive electrode plate  110  and the negative electrode plate  120 , and protrudes upward and downward from the positive electrode plate  110  and the negative electrode plate  120 . 
     As discussed hereinbefore, in the electrode assembly  100  in accordance with one embodiment of the present invention, the positive elide tab  140  and the negative electrode tab  150  are attached to the outer periphery of the electrode assembly, and the protective tape  160  is attached to the positive electrode tab  140  and the negative electrode tab  150 . Out of the front positive electrode non-coating portions  113 A of the positive electrode plate  110  in the inner periphery of the electrode assembly, the first lamination tape  170 A is attached to the first front positive electrode non-coating portion  113 AA, whereas the second lamination tape  170 B is attached to the second front positive electrode non-coating portion  113 AB. 
     Hereinafter, attachment of the lamination tape  170  ( 170 A, 170 B) to the front positive electrode non-coating portion  113 A of the positive electrode plate  110  will be described in more detail. 
     The first and second lamination tapes  170 A,  170 B are prepared to have the same length as the first and second front positive electrode non-coating portions  113 AA,  113 AB of the positive electrode plate  110  and preferably are precisely attached to the first front positive electrode non-coating portion  113 AA and the second front positive electrode non-coating portion  113 AB, respectively. In this way, the tapes  170 A,  170 B cover all of the non-coating portions  113 AA,  113 AB. 
     However, a length of the first and second lamination tapes  170 A,  170 B may be not identical with a length of the first and second front positive electrode non-coating portions  113 AA,  113 AB of the positive electrode plate  110 , or one of the first and second lamination tapes  170 A,  170 B may have a length shorter or longer than that of the other one. 
     Unfortunately, the tapes may be attached to incorrect sites during attachment of the first and second lamination tapes  170 A,  170 B to the first and second front positive electrode non-coating portions  113 AA,  113 AB. 
     When such an error occurs during a manufacturing process, the first front positive electrode non coating portion  113 AA or second front positive electrode non-coating portion  113 AB of the positive electrode plate  110  may partially exhibit the region which is not insulated by the lamination tape. 
     According to the present invention, when such a manufacturing process problem occurs, the non-insulated portion due to no attachment of the lamination tape (usually occurring in end parts of the non-coating portion), i.e. the end of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  is cut by a certain length. That is, the end of the front positive electrode non-coating portion  113 A is cut to remove the portion to which the lamination tape was not attached, under the condition where the first and second lamination tapes  170 A,  170 B are attached to the front and rear surfaces of the positive electrode non-coating portion  113 A. 
     More specifically, the end of the front positive electrode non-coating portion  113 A may be cut using two different methods. 
     Reference is made to  FIG. 3  which shows one of two cutting methods. According to the method of  FIG. 3 , under the condition where a length of the second lamination tape  170 B attached to the second front positive electrode non-coating portion  113 AB is shorter than the first lamination tape  170 A attached to the first front positive electrode non-coating portion  113 AA, the cutting is made based on the lamination tape having a shorter length. That is, the cutting is performed along the end (E) of the second lamination tape  170 B as a cutting line (C). As described above, when the end (E) of the second lamination tape  170 B having a relatively short length is cut, the first front positive electrode non-coating portion  113 AA is insulated from the outside by the first lamination tape  170 A. Further, the second front positive electrode non-coating portion  113 AB is also insulated by the second lamination tape  170 B. 
     Therefore, front and rear surfaces of the front positive electrode non-coating portion  113 A of the positive electrode plate  100  are completely insulated by the lamination tapes  170  ( 170 A, 170 B) as the lamination tape covers the length of the uncoated portions. 
     Referring to  FIG. 4  illustrating another method of cutting, the same condition applies where a length of the second lamination tape  170 B attached to the second front positive electrode non-coating portion  113 AB is shorter than the first lamination tape  170 A attached to the first front positive electrode non-coating portion  113 AA. The cutting is made along a cutting line (C) defined inside the end (E) of the second lamination tape  170 B having a shorter length. As described above, when the cutting is carried out by defining the cutting line (C) inside the end (E) of the second lamination tape  170 B, the first front positive electrode non-coating portion  113 AA is insulated from the outside by the first lamination tape  170 A. Further, the second front positive electrode non-coating portion  113 AB is also insulated by the second lamination tape  170 B. 
     In this manner, when the inside of the second lamination tape  170 B having a shorter length is cut, it is possible to solve the problem of inferior goods due to cutting errors which may occur during the cutting process of the end (E) of the second lamination tape  170 B. 
     The aforesaid cutting methods are illustrated for the case where a length of the second lamination tape  170 B is shorter. On the other hand, where a length of the first lamination tape  170 A is shorter, a cutting process is done along the end of the first lamination tape  170 A as a cutting line. 
     Hereinafter, a detailed description will be given to illustrate the prevention of an internal short circuit by an electrode assembly in accordance with one embodiment of the present invention. 
     The positive electrode tab  140  and the negative electrode tab  150  are provided on the outer periphery of the electrode assembly  100  in accordance with one embodiment of the present invention. 
     For the inner periphery of the electrode assembly  100 , the lamination tape  170  is attached to the front positive electrode non-coating portion  113 A of the positive electrode plate  110 . The lamination tape  170  is composed of first and second lamination tapes  170 A,  170 B. The first and second lamination tapes  170 A,  170 B are respectively attached to the first and second front positive electrode non-coating portions  113 AA,  113 AB, which correspond to both sides of the front positive electrode non-coating portion  113 A of the positive electrode plate  110 . When any one front non-coating portion of the first front positive electrode non-coating portion  113 AA and the second front positive electrode non-coating portion  113 AB is not completely insulated by the first and second lamination tapes  170 A,  170 B, the end of the front positive electrode non-coating portion  113 A of the positive electrode plate  100  will be cut as necessary. Therefore, first and second front positive electrode non-coating portions  113 AA,  113 AB are preferably completely insulated from the outside by the first and second lamination tapes  170 A,  170 B. 
     In this manner, the front and rear surfaces of front positive electrode non-coating portion  113 A of the positive electrode plate  110  are insulated from the negative electrode active material layers  122 A,  122 B of the adjacent negative electrode plate  120 , even when damage or shrinkage of the separators  130 ,  130 ′ occurs due to internal heat generation in the inner periphery of the electrode assembly  100 . As a result, it is possible to fundamentally prevent a short circuit which may occur on the inner periphery of the electrode assembly  100 . 
     Hereinafter, an electrode assembly in accordance with another embodiment of the present invention will be described in more detail. 
     Referring to  FIGS. 5A and 5B , an electrode assembly  200  in accordance with another embodiment of the present invention includes a positive electrode plate  110 , a negative electrode plate  120  and a separator  130 , and is prepared by stacking the positive electrode plate  110 , the negative electrode plate  120  and the separator  130  disposed therebetween and winding the resulting stacked structure into a jelly roll shape. 
     Further, a battery construction comprising the positive electrode plate  110 , the negative electrode plate  120  and the separator  130 , a positive electrode tab  140 , a negative electrode tab  150  and a protective tape  160  is also identical with one embodiment of the present invention. Like numbers refer to like elements in previously described figures, so details thereof will be omitted hereinafter. 
     In the electrode assembly  200  in accordance with another embodiment of the present invention, a first lamination tape  270 A is attached only to a first front positive electrode non-coating portion  113 AA in a front positive electrode non-coating portion  113 A of the positive electrode plate. Further, a second lamination tape  270 B is attached to the region oppositely corresponding to the second front positive electrode non-coating portion  113 AB, in the negative electrode active material layer  122 B of the negative electrode current collector  121  of the negative electrode plate  120  which is faced opposite to the positive electrode plate  110  with the separator  130  therebetween. 
     Hereinafter, a detailed description will be given to illustrate the prevention of an internal short circuit by application of the electrode assembly  200  constructed as above. 
     The positive electrode tab  140  and the negative electrode tab  150  are provided on the outer periphery of the electrode assembly  200 . 
     For the inner periphery of the electrode assembly  200 , the first lamination tape  270 A is attached to a first front positive electrode non-coating portion  113 AA of the positive electrode plate  110 . The first lamination tape  270 A is attached to the first front positive electrode non-coating portion  113 AA of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  and completely covers the first front positive electrode non-coating portion  113 AA, such that the first front positive electrode non-coating portion  113 AA and an active material layer  122 A of the negative electrode plate  120 , which are arranged opposite to each other, are insulated. 
     Further, the second lamination tape  270 B is attached to a region of the negative electrode active material layer  122 B of the negative electrode current collector  121  to which a second front positive electrode non-coating portion  113 AB is oppositely faced. 
     Accordingly, the first front positive electrode non-coating portion  113 AA of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  is insulated from the negative electrode active material layer  122 A by the first lamination tape  270 A, even when damage or shrinkage of the separators  130 , 130 ′ occurs. Further, a second front positive electrode non-coating portion  113 AB of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  is insulated from the corresponding opposite negative electrode active material layer  122 B by the second lamination tape  270 B. 
     As a consequence, it is possible to fundamentally prevent a short circuit which occurs on the inner periphery of the electrode assembly  200 . 
     Hereinafter, an electrode assembly in accordance with a further embodiment of the present invention will be described in more detail. 
     Referring to  FIGS. 6A and 6B , an electrode assembly  300  in accordance with a further embodiment of the present invention includes a positive electrode plate  110 , a negative electrode plate  120  and a separator  130 , and is prepared by stacking the positive electrode plate  110 , the negative electrode plate  120  and the separator  130  disposed therebetween and winding the resulting stacked structure into a jelly roll shape. 
     Further, a battery construction comprising the positive electrode plate  110 , the negative electrode plate  120  and the separator  130 , a positive electrode tab  140 , a negative electrode tab  150  and a protective tape  160  is also identical with one embodiment of the present invention. Like numbers refer to like elements in previously described figures, so details thereof will be omitted hereinafter. 
     In the electrode assembly  300  in accordance with a further embodiment of the present invention, a first lamination tape  370 A is attached only to a second front positive electrode non-coating portion  113 AB of a front positive electrode non-coating portion  113 A of the positive electrode plate. Further, a second lamination tape  370 B is attached to the region oppositely corresponding to the first front positive electrode non-coating portion  113 AA of the positive electrode plate, in the negative electrode active material layer  122 A which is faced opposite to the front positive electrode non-coating portion  113 A with the separator  130 ′ therebetween. 
     Hereinafter, a detailed description will be given to illustrate the prevention of an internal short circuit by application of the electrode assembly  300  constructed as above. 
     The positive electrode tab  140  and the negative electrode tab  150  are provided on an outer periphery of the electrode assembly  300 . 
     On the inner periphery of the electrode assembly  300 , the first lamination tape  370 A is attached to a second front positive electrode non-coating portion  113 AB of the positive electrode plate  110 . The first lamination tape  370 A completely covers the second front positive electrode non-coating portion  113 AB, such that the second front positive electrode non-coating portion  113 AB and an active material layer  122 B of the negative electrode plate  120 , which are arranged opposite to each other, are insulated. 
     Further, the second lamination tape  370 B is attached to the negative electrode active material layer  122 A formed on a front surface of the negative electrode plate  120  which is arranged opposite to the first front positive electrode non-coating portion  113 AA. 
     Accordingly, the first front positive electrode nonpaying portion  113 AA of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  is insulated from the negative electrode active material layer  122 A by the second lamination tape  370 B, even when damage or shrinkage of the separators  130 , 130 ′ occurs. Further, a second front positive electrode non-coating portion  113 AB of the front positive electrode non-coating portion  113 A of the positive electrode plate  110  is insulated from the negative electrode active material layer  122 B of the negative electrode plate  120  by the first lamination tape  370 A. 
     As a consequence, it is possible to fundamentally prevent a short circuit which occurs on the inner periphery of the electrode assembly  300 . 
     The electrode assemblies prepared according to the aforesaid embodiments of the present invention can be applied to the lithium secondary battery. 
     The lithium secondary batteries may be classified into different categories based on shapes of the battery case, for example polygonal, cylindrical and pouch shapes. 
     Referring to  FIGS. 7A and 7B , a secondary battery  10  having a pouch-type case is shown. 
     The pouch-type lithium secondary battery  10  includes a first case  12  having an internal space  11  to house an electrode assembly  100  and a second case  13  for sealing the open upper part of the first case  12 . The first and second cases  12 , 13  are formed of aluminum or aluminum alloy. 
     Therefore, the pouch-type secondary battery  10  is fabricated by installing the electrode assembly  100  in the internal space  11  of the first case  12  and hermetically sealing a sealing part between the first case  12  and the second case  13  to thereby prepare a unit cell of the pouch-type secondary battery. 
     The pouch-type secondary battery  10  using the electrode assembly  100  in accordance with one embodiment of the present invention exhibits no occurrence of a short circuit between an electrode non-coating portion and a negative electrode active material layer  122 , since front and rear surfaces of the front positive electrode non-coating portion  113 A are insulated by lamination tapes  170 A, 170 B in the inner periphery of the electrode assembly  100  as described above. As a result, the risk of an internal short circuit in the fabricated battery is significantly decreased to thereby improve safety of the battery. 
     Referring to  FIG. 8 , a secondary battery  20  having a polygonal-type case is shown. 
     The polygonal-type lithium secondary battery  20  includes an open-topped generally rectangular can  21  having an internal space  22  to house an electrode assembly  100  and a cap assembly  23  for delivering electric current of the electrode assembly  100  to the outside while sealing the open upper part of the can  21  after installation of the electrode assembly  100 . 
     Therefore, the polygonal-type lithium secondary battery  20  is fabricated by installing the electrode assembly  100  in the internal space  22  of the can  21  and hermetically sealing the open upper part of the can  21  with the cap assembly  23  to thereby prepare a unit cell of the polygonal-type secondary battery. 
     In the polygonal-type lithium secondary battery  20  of the present invention, the cap assembly  23  includes a cap plate through which an electrode terminal of the electrode assembly passes, an insulating plate, a terminal plate, and the like. Even though details of the cap assembly  23  are not described, it is to be understood that all of technical constructions known in the art fall within the scope of the present invention. 
     The polygonal-type lithium secondary battery  20  using the electrode assembly  100  in accordance with one embodiment of the present invention exhibits no occurrence of a short circuit between an electrode non-coating portion and a negative electrode active material layer  122 , because front and rear surfaces of the front positive electrode non-coating portion  113 A are insulated by lamination tapes  170 A, 170 B in the inner periphery of the electrode assembly  100  as described above. As a result, the risk of an internal short circuit in the fabricated battery is significantly decreased to thereby improve safety of the battery. 
     Referring to  FIG. 9 , a secondary battery  30  having a cylindrical case is shown. 
     The cylindrical lithium secondary battery  30  includes an open-topped cylindrical can  31  having an internal space  32  to house an electrode assembly  100  and a cap assembly  33  for delivering electric current of the electrode assembly  100  to the outside while sealing the open upper part of the cylindrical can  31  after installation of the electrode assembly  100 . 
     Therefore, the cylindrical lithium secondary battery  30  is fabricated by installing the electrode assembly  100  in the internal space  32  of the cylindrical can  31  and hermetically sealing the open upper part of the cylindrical can  31  with the cap assembly  33  to thereby prepare a unit cell of the cylindrical secondary battery. 
     In the cylindrical lithium secondary battery  30  of the present invention, the cap assembly  33  includes a cap up to which an electrode terminal of the electrode assembly is electrically connected, a safety vent, an insulator, a cap down, and the like. Even though details of the cap assembly  23  are not described herein, it is to be understood that all of technical constructions known in the art fall within the scope of the present invention. 
     The cylindrical lithium secondary battery  30  using the electrode assembly  100  in accordance with one embodiment of the present invention exhibits no occurrence of a short circuit between an electrode non-coating portion and a negative electrode active material layer  122 , because front and rear surfaces of the front positive electrode non-coating portion  113 A are insulated by lamination tapes  170 A,  170 B in the inner periphery of the electrode assembly  100  as described above. As a result, the risk of an internal short circuit in the fabricated battery is significantly decreased to thereby improve safety of the battery. 
     Meanwhile, in the cylindrical lithium secondary battery  30  of the present invention, when the positive electrode tab  140  of the electrode assembly  100  is allowed to protrude upward from the upper part of the electrode assembly  100 , the negative electrode tab  150  is allowed to protrude downward from the bottom of the electrode assembly  100 , thus resulting in electrical connection with the cylindrical can  31 . 
     Even though the pouch-, polygonal- and cylinder-type lithium secondary batteries were exemplified with application of the electrode assembly  100  in accordance with one embodiment of the present invention, it should be understood that the same desired effects can be achieved with application of the electrode assembly ( 200 , 300 ) in accordance with other embodiments of the present invention.