Abstract:
A pouch type battery, including a pouch type bare cell having a terrace and having an electrode tab adjacent to the terrace, the terrace being an empty space defined where a sealing area of the electrode tab is not bent, the sealing area positioned in a direction in which the electrode tab extends, a protective circuit board electrically connected to the electrode tab, the protective circuit board positioned in the terrace and including a protection circuit, an upper case supporting the protective circuit board and encasing an upper portion of the bare cell, and a first barrier protruding downwardly from the upper case and electrically separating the protective circuit board from the electrode tab.

Description:
BACKGROUND 
       [0001]    1. Field 
         [0002]    Embodiments relate to a pouch type battery. 
         [0003]    2. Description of the Related Art 
         [0004]    In general, unlike primary batteries that are not rechargeable, secondary batteries are rechargeable batteries. Secondary batteries have come into widespread use for small, advanced electronic apparatuses, such as cellular phones, personal digital assistants (PDAs), notebook computers, and so on. For example, lithium secondary batteries operate at a voltage of 3.6 V and are widely used as a power source for electronic apparatuses, since the operating voltage of the lithium secondary battery is approximately 3 times higher than that of nickel-cadmium (Ni—Cd) batteries or nickel-hydride (Ni—MH) batteries, and since the lithium secondary batteries have a high energy density, i.e., a high amount of electrical power per unit weight. 
         [0005]    A lithium secondary battery may employ a lithium-based oxide as a positive electrode active material and a carbon material as a negative electrode active material. In addition, the lithium secondary battery may have various shapes, such as a cylindrical shape, a prismatic shape, and a pouch shape. 
         [0006]    A pouch type battery may include a pouch-shaped bare cell and a protective circuit module. The pouch-shaped bare cell may include, e.g., a jellyroll-type electrode assembly and a pouch accommodating the electrode assembly. 
       SUMMARY 
       [0007]    It is a feature of an embodiment to provide a pouch type battery, which may be configured to reduce the entire length of the battery by placing a protective circuit module inside a terrace that is an empty space of a pouch-shaped bare cell. 
         [0008]    At least one of the above and other features and advantages may be realized by providing a pouch type battery, including a pouch type bare cell having a terrace and having an electrode tab adjacent to the terrace, the terrace being an empty space defined where a sealing area of the electrode tab is not bent, the sealing area positioned in a direction in which the electrode tab extends, a protective circuit board electrically connected to the electrode tab, the protective circuit board positioned in the terrace and including a protection circuit, an upper case supporting the protective circuit board and encasing an upper portion of the bare cell, and a first barrier protruding downwardly from the upper case and electrically separating the protective circuit board from the electrode tab. 
         [0009]    The bare cell may be a polymeric cell using a polymer as electrolyte. 
         [0010]    The bare cell may include an electrolyte contained in a pouch, and the electrode tab may extend from inside the pouch to outside the pouch, the pouch being sealed around the electrode tab at the sealing area. 
         [0011]    The electrode tab may be bent to be electrically connected to the protective circuit board. 
         [0012]    The electrode tab may bend downward so as to fold back toward a bottom of the terrace, and bend sideways so as to extend along the bottom of the terrace. 
         [0013]    The pouch type battery may further include a lower case encasing a lower portion and sides of the bare cell, and a second barrier protruding upwardly from the lower case so as to be located between the electrode tab and a first side end of the upper case. The second barrier may be coupled to the first side end of the upper case, the first side end of the upper case being located opposite to the terrace with respect to the electrode tab. 
         [0014]    The lower case may be molded into the periphery of the bare cell to be integrally formed with the bare cell. 
         [0015]    The electrode tab may bend downward so as to fold over an extending portion of the lower case and back toward a bottom of the terrace, and bend sideways so as to extend along a surface of the lower case and along the bottom of the terrace. 
         [0016]    The electrode tab may include a bend of about 180 degrees where it bends downward, and the second barrier may protrude upwardly to a height that is greater than a height of the electrode tab at the bend of about 180 degrees. 
         [0017]    The upper case may cover an uppermost portion of the second barrier. 
         [0018]    At least one of the above and other features and advantages may be realized by providing a method of making a pouch type battery, the method including forming a bare cell, the bare cell including an electrode assembly disposed in a pouch and an electrode tab extending from inside the pouch to outside the pouch through a sealing area, molding a lower case to the bare cell, bending the electrode tab so that it is adjacent to a terrace formed in the bare cell, the terrace being an empty space defined where the sealing area of the electrode tab is not bent, the sealing area positioned in a direction in which the electrode tab extends, mounting a protective circuit board in the terrace of the bare cell, electrically connecting the protective circuit board and the electrode tab to one another, and encasing the protective circuit board and an upper portion of the bare cell with an upper case, a first barrier protruding downwardly from the upper case and positioned between the protective circuit board and the electrode tab so as to prevent an electrical short between the protective circuit board and the electrode tab. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The above and other features and advantages will become more apparent to those of skill in the art by describing in detail example embodiments with reference to the attached drawings, in which: 
           [0020]      FIG. 1  illustrates a vertical sectional view of a pouch type battery according to a first embodiment; 
           [0021]      FIG. 2  illustrates a vertical sectional view of a pouch type battery according to a second embodiment; 
           [0022]      FIG. 3  illustrates a perspective view showing a lower case integrally molded into a bare cell of the pouch type battery illustrated in  FIG. 2 ; 
           [0023]      FIG. 4  illustrates a perspective view showing a protective circuit module mounted in a terrace of the bare cell of the pouch type battery illustrated in  FIG. 3 ; 
           [0024]      FIG. 5  illustrates a perspective view showing an upper case mounted on the protective circuit module of the pouch type battery illustrated in  FIG. 4 ; 
           [0025]      FIG. 6  illustrates a cross-sectional view taken along a line VI-VI of  FIG. 5 ; and 
           [0026]      FIG. 7  illustrates a bottom perspective view of the upper case of the pouch type battery illustrated in  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Korean Patent Application No. 10-2010-0002633, filed on Jan. 12, 2010, in the Korean Intellectual Property Office, and entitled: “Pouch-Type Battery,” is incorporated by reference herein in its entirety. 
         [0028]    Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. 
         [0029]    In the drawing figures, the dimensions of layers and regions may be exaggerated for clarity of illustration. It will also be understood that when a layer or element is referred to as being “on” another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Further, it will be understood that when a layer is referred to as being “under” another layer, it can be directly under, and one or more intervening layers may also be present. In addition, it will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to like elements throughout. 
         [0030]      FIG. 1  illustrates a vertical sectional view of a pouch type battery according to a first embodiment. 
         [0031]    Referring to  FIG. 1 , the pouch type battery according to the first embodiment may includes a pouch type bare cell  100 , a protective circuit board  200 , an upper case  300 , and a first barrier  310 . 
         [0032]    The pouch type bare cell  100  may include an electrode assembly  101 , and a pouch  103  accommodating the electrode assembly  101 . 
         [0033]    The electrode assembly  101  may include a first electrode plate and a second electrode plate stacked or wound with a separator interposed therebetween. An electrode tab  102  may extend from a side of each electrode plate. The electrode assembly  101 , in combination with an electrolyte, provides an electrochemical means to charge and discharge. In order to enhance stability, the bare cell  100  may be a polymeric cell using a solid-state polymer or gel-state polymer as electrolyte. 
         [0034]    The pouch  103  may include an upper pouch film  103   a  and a lower pouch film  103   b . The pouch may be formed such that the electrode assembly  101  is mounted in the pouch  103 , and peripheral portions of the upper pouch film  103   a  and the lower pouch film  103   b  may be sealed to contain the electrode assembly  101  and electrolyte. 
         [0035]    To electrically connect the electrode assembly  101  to an external device, respective electrode tabs  102  connected to each of the electrode plates of the electrode assembly  101  may be exposed to the exterior of the pouch  103  through a sealing portion  110 . 
         [0036]    The pouch  103  may include a terrace  120 , the terrace  120  being an empty space of the bare cell  100  that is a portion formed when the sealing portion  110  is not bent. For example, the sealing portion  110  may be substantially flat where the pouch is sealed around the electrode tab  102 , and the electrode tab  102  may be flat where it extends from the pouch  103 . 
         [0037]    The protective circuit board  200  may be a board on which various elements  201  are mounted to form a protection circuit. The protective circuit board  200  may form a protection circuit module together with the protection circuit. The protective circuit module may serve as a safety device for cutting off a circuit to break a current when an internal temperature of the battery rises or when a voltage of the battery abruptly increases due to overheating or overdischarging of the battery, thereby preventing the combustion or explosion of the battery. 
         [0038]    The protective circuit board  200  may be electrically connected to the electrode tab  102  and may be provided inside the terrace  120 . In order to electrically connect the protective circuit board  200  to the electrode tab  102  while mounting the protective circuit board  200  in the terrace  120 , the electrode tab  102  may be bent. By forming the electrode tab  102  in a bent shape, it is not necessary to provide an additional conductor, such as a lead plate, between a connecting portion  202  of the protective circuit board  200  and the electrode tab  102 , thereby reducing costs. In an implementation, as shown in  FIG. 1 , the electrode tab  102  may include a first bent portion  102   a  bent approximately 180 degrees downwardly, and a second bent portion  102   b  further bent approximately 90 degrees outwardly. 
         [0039]    Along with a lower case  1500 , described below in connection with the second embodiment, the upper case  300  may insulate and/or protect a core pack including the bare cell  100  and the protective circuit board  200 . The upper case  300  may support the protective circuit board  200  while encasing an upper portion of the bare cell  100 . 
         [0040]    The first barrier  310  may protrude downwardly from the upper case  300  and electrically separates, i.e., disconnects, the protective circuit board  200  provided inside the terrace  120  from the electrode tab  102 . Thus, the first barrier  310  provided between the protective circuit board  200  and the electrode tab  102  may help prevent an undesired electrical connection or short-circuit between the protective circuit board  200  and the electrode tab  102 . 
         [0041]    Hereinafter, a pouch type battery according to a second embodiment will be described with reference to  FIGS. 2 and 7 . 
         [0042]      FIG. 2  illustrates a vertical sectional view of the pouch type battery according to the second embodiment, and  FIG. 7  illustrates a bottom perspective view of the upper case of the pouch type battery illustrated in  FIG. 2 . 
         [0043]    Referring to  FIG. 2 , the pouch type battery according to the second embodiment may include the pouch type bare cell  100 , the protective circuit board  200 , an upper case  1300 , the first barrier  310 , a lower case  1500 , and a second barrier  1510 . 
         [0044]    The pouch type bare cell  100  and the protective circuit board  200  may be substantially the same as those of the previous embodiment, and thus a detailed description thereof will be omitted to avoid repetition. 
         [0045]    Along with the lower case  1500 , which will be described below, the upper case  1300  may insulate and/or protect the core pack including the bare cell  100  and the protective circuit board  200 . The upper case  1300  may support the protective circuit board  200  while encasing an upper portion of the bare cell  100 . 
         [0046]    The upper case  1300  may include a first side end  1301  (coupled to the second barrier  1510  to be described below) that is located opposite to the terrace  120  with respect to the electrode tab  102 . The first side end  1301  provided in the upper case  1300  is shown in  FIG. 7  in greater detail. 
         [0047]    The first barrier  1310  may protrude downwardly from the upper case  1300  and electrically separates the protective circuit board  200  provided inside the terrace  120  from the electrode tab  102 . Thus, the first barrier  1310  provided between the protective circuit board  200  and the electrode tab  102  may help prevent an electrical short between the protective circuit board  200  and the electrode tab  102 . The first barrier  1310  provided in the upper case  1300  is shown in  FIG. 7  in greater detail. 
         [0048]    Along with the upper case  1300 , the lower case  1500  may insulate and/or protect the core pack including the bare cell  100  and the protective circuit board  200 . The lower case  1500  may encase a lower portion and sides of the bare cell  100 . In an implementation, in order to couple the lower case  1500  to the bare cell  100  without using a separate connection unit, the lower case  1500  may be molded into the periphery of the bare cell  100  to then be integrally formed with the bare cell  100 . 
         [0049]    The second barrier  1510  may protrude upwardly from the lower case  1500 , so as to extend between the electrode tab  102  and the first side end  1301  of the upper case  1300 . The second barrier  1510  may be is coupled to the first side end  1301  of the upper case  1300 . In an implementation, the first side end  1301  of the upper case  1300  and the second barrier  1510  of the lower case  1500  may be coupled to each other by means of a connection unit “C.” The connection unit “C” may include a connecting protrusion  1511  formed at the second barrier  1510  of the lower case  1500 , and a connecting groove  1302  formed at the first side end  1301  of the upper case  1300 . Accordingly, since the upper case  1300  may be fixed to the lower case  1500  molded into the bare cell  100 , the upper case  1300  may be securely fixed to the bare cell  100 . 
         [0050]    Hereinafter, a method of manufacturing the pouch type battery of the second embodiment will be described with reference to  FIGS. 3 through 6 . 
         [0051]      FIG. 3  illustrates a perspective view showing a lower case integrally molded into a bare cell of the pouch type battery illustrated in  FIG. 2 ,  FIG. 4  illustrates a perspective view showing a protective circuit module mounted in a terrace of the bare cell of the pouch type battery illustrated in  FIG. 3 ,  FIG. 5  illustrates a perspective view showing an upper case mounted on the protective circuit module of the pouch type battery illustrated in  FIG. 4 , and  FIG. 6  illustrates a cross-sectional view taken along a line VI-VI of  FIG. 5 . 
         [0052]    First, referring to  FIG. 3 , the electrode tab  102  may be bent such that it may be placed inside the terrace  120 , which is an empty space of the pouch type bare cell  100 . Then, the lower case  1500  may be molded into the pouch type bare cell  100  to make the lower case  1500  and the pouch type bare cell  100  integrally formed with each other. 
         [0053]    Next, referring to  FIG. 4 , the protective circuit board  200  may be mounted in the empty space of the bare cell  100 , that is, the terrace  120 . Here, the connecting portion  202  of the protective circuit board  200  may be connected to the electrode tab  102 . 
         [0054]    Then, referring to  FIG. 5 , the upper case  1300  encases the protective circuit board  200  and an upper portion of the bare cell  100 .  FIG. 6  shows a result of encasing the protective circuit board  200  and an upper portion of the bare cell  100 , with the first barrier  1310  of the upper case  1300  positioned between the protective circuit board  200  and the electrode tab  102  so as to prevent an electrical short between the protective circuit board  200  and the electrode tab  102 . In addition, referring back to  FIG. 2 , the casing may also allow the connecting protrusion  1511  of the second barrier  1510  provided at the lower case  1500  to be engaged with the connecting groove  1302  of the first side end  1301  of the upper case  1300 . 
         [0055]    The pouch type battery according to the example embodiments of the present invention described herein may afford one or more advantages. For example, where a protective circuit board is provided inside a terrace, which is an empty space of a bare cell, the entire length of the pouch type battery may be reduced as compared to the conventional pouch type battery. Consequently, from the viewpoint of miniaturization of an electronic device, batteries that are shortened in their entire lengths may have a much wider range of applicability. Also, a barrier may be provided between a protective circuit board and an electrode tab so that an electrical short between the protective circuit board and the electrode tab may be prevented. 
         [0056]    Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.