Abstract:
A rack and an energy storage system, the rack including guide plates for co-operation with battery trays to be arranged in the rack; tray supporting units for holding the battery trays, the tray supporting units being coupled with the guide plates; and tray fixing units on the guide plates, the tray fixing units fixing the tray supporting units in place and substantially constraining the tray supporting units against displacement.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority under 35 U.S.C. §119 to U.S. Provisional Application No. 61/725,646, filed on Nov. 13, 2012, and entitled: “Energy Storage System,” which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    Embodiments relate to a rack and an energy storage system. 
         [0004]    2. Description of the Related Art 
         [0005]    An energy storage system may be used in association with a renewable energy and power system, e.g., a solar cell. The energy storage system may be configured to store power when power demanded from a load is small, and then use the stored power when the demand for power is increased. The energy storage system may include a large quantity of secondary batteries, which may also be used in electronic devices, such as cellular phones, or notebook computers. 
       SUMMARY 
       [0006]    Embodiments are directed to a rack and an energy storage system. 
         [0007]    The embodiments may be realized by providing a rack including guide plates for co-operation with battery trays to be arranged in the rack; tray supporting units for holding the battery trays, the tray supporting units being coupled with the guide plates; and tray fixing units on the guide plates, the tray fixing units fixing the tray supporting units in place and substantially constraining the tray supporting units against displacement. 
         [0008]    The rack may further including a top frame; a bottom frame parallel with the top frame; side frames extending perpendicularly with respect to the top frame and the bottom frame and connecting the top frame and the bottom frame; shelf frames extending in parallel with the top frame and the bottom frame on a front and a back of the rack and being coupled with the side frames. 
         [0009]    The guide plates may each include a first region extending in parallel with the top frame and bottom frame, and a second region extending perpendicularly from the first region, the second region being coupled with the side frames, and the tray fixing units may be on an inner surface of the second region. 
         [0010]    The tray supporting units may each include a first plate, a bottom surface of the first plate being supported by the first region of the guide plate, and a second plate extending perpendicularly from the first plate along a front of the rack. 
         [0011]    The tray supporting units may be inserted into the front of the rack. 
         [0012]    The tray fixing unit may be coupled with a top surface of the first plate of the tray supporting unit. 
         [0013]    The tray fixing unit may include a coupling region coupled with the inner surface of the second region of the guide plate, and a fixing region contacting a top surface of the first plate of the tray supporting unit such that a portion of the tray supporting unit is between the fixing region of the tray fixing unit and the first region of the guide plate. 
         [0014]    The fixing region of each tray fixing unit may include a pair of first fixing regions extending away from the coupling region, and a second fixing region at ends of the first fixing regions, the second fixing region being spaced apart from the second region of the guide plate and extending in parallel with the coupling region, and bottom surfaces of the first fixing region and the second fixing region may contact the top surface of the first plate of the tray supporting unit. 
         [0015]    The pair of first fixing regions may extend away from the coupling region by a distance of about 10 mm or greater. 
         [0016]    A length of the bottom surface of the second fixing region that contacts the top surface of the first plate of the tray supporting unit may be about 60 mm or greater. 
         [0017]    The fixing region of each of the tray fixing units may extend perpendicularly from the coupling region and may include a pair of first fixing regions extending in parallel with the top frame and the bottom frame, a second fixing region spaced apart from and extending in parallel with the pair of first fixing regions, a bottom surface of the second fixing region contacting the top surface of the first plate of the tray supporting unit, and a pair of connecting fixing regions connecting an end of each of the first fixing regions and an end of the second fixing region 
         [0018]    The connecting fixing regions may be inclined with respect to planes of the first fixing regions and the second fixing region. 
         [0019]    The fixing region may extend perpendicularly from the coupling region by a distance of about 10 mm or greater. 
         [0020]    A length of the bottom surface of the second fixing region that contacts the top surface of the first plate of the tray supporting unit may be about 50 mm or greater. 
         [0021]    The embodiments may also be realized by providing an energy storage system including a rack for arranging battery trays in a vertical stack, the rack including guide plates for co-operation with the battery trays to be arranged in the rack; tray supporting units for holding the battery trays, the tray supporting units being coupled with the guide plates; and tray fixing units on the guide plates, the tray fixing units vertically fixing the tray supporting units in place and substantially constraining the tray supporting units against vertical displacement. 
         [0022]    The guide plates may each include a first region extending perpendicularly with respect to the vertical stack, and a second region extending perpendicularly from the first region, the tray fixing units may be on an inner surface of the second region, and the tray supporting units may each include a first plate, a bottom surface of the first plate being supported by the first region of the guide plate, and a second plate extending perpendicularly from the first plate along a front of the rack. 
         [0023]    Each of the tray fixing units may include a coupling region coupled with the inner surface of the second region of the guide plate, and a fixing region contacting a top surface of the first plate of the tray supporting unit such that a portion of the tray supporting unit is between the fixing region of the tray fixing unit and the first region of the guide plate. 
         [0024]    The energy storage system may further include the battery trays, the battery trays being supported by the tray supporting unit, and each including at least one battery cell. 
         [0025]    The energy storage system may further include connector units on a back of the rack, a number of connector units corresponding with a number of battery trays, the connector units being connected to the battery cells in the battery trays. 
         [0026]    The energy storage system may further include at least one of a battery management box and a switch box, the battery management box being connected to the connector units and managing charging and discharging of the battery cells in the battery trays; and the switch box being connected to the connector units and including a protection circuit device for protecting the battery cells in the battery trays. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]    Features will become apparent to those of ordinary skill in the art by describing in detail exemplary embodiments with reference to the attached drawings in which: 
           [0028]      FIG. 1  illustrates a perspective view of an energy storage system according to an embodiment; 
           [0029]      FIG. 2  illustrates an exploded perspective view of a battery tray of the energy storage system according to an embodiment; 
           [0030]      FIG. 3  illustrates a perspective view of a tray supporting unit of the energy storage system according to an embodiment; 
           [0031]      FIG. 4  illustrates a perspective view of a rack of the energy storage system according to an embodiment; 
           [0032]      FIG. 5  illustrates an enlarged view of a portion of the rack of  FIG. 4 , in which the tray fixing unit is included in the rack of the energy storage system according to an embodiment; 
           [0033]      FIG. 6  illustrates a state in which the tray supporting unit is coupled with the tray fixing unit shown in  FIG. 5 ; 
           [0034]      FIG. 7  illustrates a cross-sectional view taken along line A-A′ of  FIG. 4 ; 
           [0035]      FIG. 8  illustrates a perspective view of a tray fixing unit of the energy storage system according to an embodiment; 
           [0036]      FIG. 9  illustrates a rear view of a state in which battery trays in the rack are connected in the energy storage system according to an embodiment; 
           [0037]      FIG. 10  illustrates an enlarged view of a portion of a rack in which the tray fixing unit is included in the rack of the energy storage system according to another embodiment; 
           [0038]      FIG. 11  illustrates a cross-sectional view of a rack in which the tray fixing unit is included in the rack of the energy storage system according to another embodiment; and 
           [0039]      FIG. 12  illustrates an enlarged view of the tray fixing unit in the energy storage system according to another embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0040]    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 exemplary implementations to those skilled in the art. 
         [0041]    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 element, it can be directly on the other element, or intervening elements may also be present. In addition, it will also be understood that when an element is referred to as being “between” two elements, it can be the only element between the two elements, or one or more intervening elements may also be present. Like reference numerals refer to like elements throughout. 
         [0042]      FIG. 1  illustrates a perspective view of an energy storage system according to an embodiment,  FIG. 2  illustrates an exploded perspective view of a battery tray of the energy storage system according to an embodiment,  FIG. 3  illustrates a perspective view of a tray supporting unit of the energy storage system according to an embodiment,  FIG. 4  illustrates a perspective view of a rack of the energy storage system according to an embodiment,  FIG. 5  illustrates an enlarged view of a portion of the rack in which the tray fixing unit is included in the rack of the energy storage system according to an embodiment,  FIG. 6  illustrates a state in which the tray supporting unit is coupled with the tray fixing unit shown in  FIG. 5 ,  FIG. 7  illustrates a cross-sectional view taken along the line A-A′ of  FIG. 4 ,  FIG. 8  illustrates a perspective view of a tray fixing unit of the energy storage system according to an embodiment, and  FIG. 9  illustrates a rear view illustrating a state in which battery trays in the rack are connected in the energy storage system according to an embodiment. 
         [0043]    The energy storage system  100  may include battery trays  110 , a tray supporting unit  120 , a rack  130 , connector units  150 , a battery management box  160 , a switch box  170 , power supply wires  180 , and communication wires  190 . In an implementation, the energy storage system  100  may further include covers  140  coupled to front and side surfaces of the rack  130 . 
         [0044]    The battery trays  110  may be accommodated in the rack  130 . The battery trays  110  may each include a first case  111  and a second case  112 . The first case  111  may be box-shaped and may have an accommodation space inside. The first case may include a plurality of partitions  113  in an internal space to separately accommodate a plurality of battery cells  114 . The second case  112  may be plate-shaped and may be coupled to the first case  111  accommodating the plurality of battery cells  114 . In an implementation, the first case  111  and the second case  112  may be made of an insulating material, e.g., a plastic material. A number of the battery trays  110  may be adjusted according to a size of the rack  130 . In an implementation, although not shown, each of the battery trays  110  may further include a battery management system (BMS) embedded therein to control charging and discharging of the battery cells  114 . 
         [0045]    The tray supporting unit  120  may include a plurality of tray supporting units  120 , which may be inserted into the rack  130  to be coupled thereto. For example, the tray supporting units  120  may be inserted into a front side of the rack  103 . In addition, the tray supporting unit  120  may support bottom portions of the battery trays  110  to facilitate safe mounting of the battery trays  110  in the rack  130 . Positions of the tray supporting units  120  may be fixed within the rack  130 , thereby allowing the battery trays  110  positioned thereon to be safety placed in the rack  130 . 
         [0046]    The tray supporting unit  120  may include a first plate  121  (formed or extending in one direction) to be inserted into the rack  130 , and a second plate  122  (formed to be perpendicular to the first plate  121 ). The first plate  121  may be inserted into the rack  130 , and a position of a side portion  121   a  of the first plate  121  may be fixed within the rack  130 , thereby reducing the likelihood of and/or preventing the battery trays  110  from vibrating in the rack  130 , even in the event of an external vibration being applied to the rack  130 . 
         [0047]    The rack  130  may include a top frame  131 , a pair of side frames  132  (downwardly extending from the top frame  131  to be perpendicular to the top frame  131 ), and a bottom frame  134  at a bottom portion of the rack  130  to be connected to the side frames  132 . In an implementation, the rack  130  may include a middle frame  133  installed between the side frames  132  to be parallel to the side frames  132 . In addition, the rack  130  may include a plurality of first shelf frames  135  on a front surface between the top frame  131  and the bottom frame  134  to be parallel to the top frame  131  and the bottom frame  134 , and a plurality of second shelf frames  136  on a rear surface between the top frame  131  and the bottom frame  134 . 
         [0048]    In addition, a guide plate  137  may be formed widthwise on each of the side frames  132  (and, if present, the middle frame  133 ) to connect the first shelf frames  135  and the second shelf frames  136 . The guide plate  137  may have a length corresponding to a distance between each of the first shelf frames  135  and corresponding ones of the second shelf frames  136 , e.g., a thickness of the rack  130 . 
         [0049]    The guide plate  137  may include a first region  137   a  (extending from the first shelf frame  135  to the second shelf frame  136  on top surfaces of the first shelf frame  135  and the second shelf frame  136 ), and a second region  137   b  (vertically bent from the first region  137   a ). The first region  137   a  may support the tray supporting unit  120  from a bottom and may be fastened or coupled to the tray supporting unit  120 . The tray supporting unit  120  may move along the first region  137   a  when inserted into the rack  130 , e.g., at the front side of the rack  130 . In addition, the second region  137   b  may be a region to which the following components for fixing the tray supporting unit  120  may be coupled. 
         [0050]    The rack  130  may include a tray fixing unit  138  formed on an interior side of the second region  137   b  of the guide plate  137 . The tray fixing unit  138  may protrude on or over a top portion or surface of the tray supporting unit  120  and may support the top portion of the tray supporting unit  120 . Therefore, the tray fixing unit  138  may help control and/or suppress vertical vibration of the tray supporting unit  120 , thereby controlling and/or suppressing vibration of the battery trays  110 . 
         [0051]    For example, the tray fixing unit  138  may include a coupling region  138   a,    138   c  coupled with the second region  137   b  of the guide plate  137  at an end of the second region  137   b  of the guide plate  137 . In an implementation, a portion of the coupling region  138   a  may include at least one hole  138   b  formed therein to be coupled with the guide plate  137  by external coupler (e.g., bolts,  10 ). 
         [0052]    In addition, another portion of the coupling region  138   c  may be coupled with the second region  137   b  of the guide plate  137  at another end symmetrical to the first region  138   a.  In an implementation, the other portion of the coupling region  138   c  may be maintained at a state in which it is coupled with the guide plate  137  by, e.g., welding. 
         [0053]    The tray fixing unit  138  may include a fixing region  138   d,    138   e  contacting a top surface of the first plate  121  of the tray supporting unit  120  such that a portion of the tray supporting unit  120  is between the fixing region  138   d,    138   e  of the tray fixing unit  138  and the first region  137   a  of the guide plate  137 . The fixing region  138   d,    138   e  may include a pair of first fixing regions  138   d  protruding or extending away from the coupling region  138   a,    138   c.  The fixing region  138   d,    138   e  may include a second fixing region  138   e  between the first fixing regions  138   d.  For example, the second fixing region  138   e  may be at ends of the first fixing regions  138   d  and may be spaced apart from the second region  137   b  of the guide plate  137 . The second fixing region  138   e  may extend in parallel with the coupling region  138   a,    138   c.  For example, the second fixing region  138   e  may protrude on or over the top portion of the tray supporting unit  120 . Thus, vertical vibration of the tray supporting unit  120  may be suppressed. Therefore, it is possible to help reduce the likelihood and/or prevent the tray supporting unit  120  and the battery trays  110  from vibrating, thereby increasing stability of the energy storage system  100 . 
         [0054]    In an implementation, a length t 1  of the tray fixing unit  138  may be about 110 mm or greater. Maintaining the length t 1  of the tray fixing unit  138  at about 110 mm or greater may help ensure that the tray fixing unit  138  is coupled to the second region  137   b  of the guide plate  137 , and may provide for a length long enough to fix the tray supporting unit  120 . 
         [0055]    In an implementation, a width t 2  of the tray fixing unit  138  may be about 30 mm or greater. Maintaining the width t 2  of the tray fixing unit  138  at about 30 mm or greater may help secure a sufficient coupling strength between the coupling region  138   a,    138   c  of the tray fixing unit  138  and the guide plate  137 . 
         [0056]    In an implementation, a height t 3  of the first fixing regions  138   d  protruding from the coupling region  138   a,    138   c  may be about 10 mm or greater. Maintaining the height t 3  of the first fixing regions  138   d  at about 10 mm or greater may help ensure that the tray fixing unit  138  is able to reduce the likelihood and/or prevent edges of the side portion  121   a  of the tray supporting unit  120  from deforming while stably supporting the tray supporting unit  120 . 
         [0057]    In an implementation, a length t 4  of the second fixing region  138   e  of the tray fixing unit  138  may be about 60 mm or greater. Maintaining the length t 4  of the second fixing region  138   e  of the tray fixing unit  138  at about 60 mm or greater may help ensure that the second fixing region  138   e  is able to reduce the likelihood of and/or prevent edges of the side portion  121   a  of the tray supporting unit  120  from deforming while stably supporting the tray supporting unit  120 . 
         [0058]    In an implementation, a distance hl between the tray fixing unit  138  and the tray supporting unit  120  may be about 0.5 mm or less. Maintaining the distance hl between the tray fixing unit  138  and the tray supporting unit  120  at about 0.5 mm or less may help ensure that the tray supporting unit  120  vertically tightly contacts with the tray fixing unit  138  to, thereby reducing and/or preventing vertical vibration, and may help reduce and/or prevent deformation of the side portion  121   a  of the tray supporting unit  120  due to external vibration. 
         [0059]    The cover  140  may include a front cover  141  on a front surface of the rack  130  and a side cover  142  on a side surface of the rack  130 . The front cover  141  may include hinges at edges thereof to be opened by a user when desired. In addition, the side cover  142  may be coupled with side frames  132  of the rack  130  to protect the trays  110  provided inside. 
         [0060]    The connector units  150  may be on a rear surface of the rack  130  opposite to the front cover  141 . A number of the connector units  150  may be equal to that of the battery trays  110 , and the connector units  150  may be coupled with the battery trays  110 , respectively, to be electrically connected to the battery cells  114  in the battery trays  110 . The connector units  150  may provide paths for charging and discharging operations and communication for the battery cells  114 . 
         [0061]    The battery management box  160  may have a same size as the battery tray  110  to be accommodated in the rack  130 . The battery management box  160  may include circuit devices for controlling communications with respective battery trays  110 . The battery management box  170  may identify states of the battery cells  114  accommodated in the battery trays  110  through the circuit devices. 
         [0062]    The switch box  170  may have the same size as the battery tray  110  to be accommodated in the rack  130 . The switch box  170  may include a protection circuit device for protecting the battery cells  114 . For example, the protection circuit device may be a fuse or switching device that disconnects a flow of current when current supplied to the battery cells  114  is greater than a current limit of the battery cells  114 . 
         [0063]    The power supply wires  180  may connect the connector units  150  and the switch box  170 . Thus, the power supply wires  180  may establish electrical connections between the battery trays  110  coupled with the connector units  150  while providing charging and discharging paths. 
         [0064]    The communication wires  190  may connect the connector units  150 , the battery management box  160 , and the switch box  170  to one another. The communication wires  190  may provide communication paths to allow the battery management box  160  to monitor states of the battery cells  114  provided in the battery trays  110 . 
         [0065]    Hereinafter, a configuration of an energy storage system according to another embodiment will be described. 
         [0066]      FIG. 10  illustrates an enlarged view of a portion of a rack in which a tray fixing unit is foamed in the rack of an energy storage system according to another embodiment,  FIG. 11  illustrates a cross-sectional view of a portion where the tray fixing unit is formed in the rack of the energy storage system according to another embodiment, and  FIG. 12  illustrates an enlarged view of the tray fixing unit in the energy storage system according to another embodiment. 
         [0067]    The same functional components as those of the previous embodiment are denoted by the same reference numerals, and the following description will focus on differences between the previous and present embodiments. 
         [0068]    Referring to  FIGS. 10 to 12 , the energy storage system according to the present embodiment may include a rack  230  coupled with tray supporting units  120 . For example, the tray supporting units  120  may be inserted into a front side of the rack  230 . 
         [0069]    The rack  230  may include tray fixing units  238  coupled with guide plates  137 . Each of the tray fixing units  238  may include a coupling region  238   a,    238   c  coupled with a second region  137   b  of each of the guide plates  137  at one end of the second region  137   b  of the guide plate  137 . The coupling region  238   a,    238   c  may include at least one hole  238   b.  In such a manner, the tray fixing units  238  may be coupled to the guide plates  137  through external couplers, e.g., bolts. 
         [0070]    The coupling region  238   a,    238   c  of the tray fixing unit  238  may include another coupling region  238   c  coupled with the guide plate  137  at another end symmetrical to the one coupling region  238   a.  The other coupling region  238   c  may be coupled with the guide plates  137  by, e.g., welding. 
         [0071]    In an implementation, the tray fixing unit  238  may include a pair of first fixing regions  238   d  protruding from the coupling region  238   a,    238   c,  and a second fixing region  238   e  between the pair of first fixing regions  238   d  to be tilted or offset with respect to the first fixing regions  238   d.  The second fixing region  238   e  may extend in a lengthwise direction of the tray fixing unit  238  and may fix a side portion  121   a  of the tray supporting unit  120 , thereby fixing the tray supporting unit  120  and battery trays. In an implementation, a pair of connecting fixing regions  238   f  may connect an end of each of the first fixing regions  238   d  and an end of the second fixing region  238   e.  In an implementation, the connecting fixing regions  2338   f  may be inclined with respect to planes of the first fixing regions  238   d  and the second fixing regions  238   e.    
         [0072]    In an implementation, a length t 5  of both of the first fixing regions  238   d  together with the second fixing region  238   e  may be about 60 mm or greater. Maintaining the length t 5  of both of the first fixing regions  238   d  together with the second fixing region  238   e  at about 60 mm or greater may help ensure that the second fixing region  238   e  is able to reduce the likelihood of and/or prevent edges of the side portion  121   a  of the tray supporting unit  120  from deforming while stably supporting the tray supporting unit  120 . 
         [0073]    In an implementation, a protrusion distance t 6  of each of the first fixing regions  238   d  and the second fixing region  238   e,  e.g., protruding from the coupling region  238   a,    238   c  of the tray fixing unit  238  may be about 10 mm or greater. Maintaining the height t 6  of each of the first fixing regions  238   d  and the second fixing region  238   e  at about 10 mm or greater may help ensure that the tray fixing unit  238  is able to help reduce the likelihood of and/or prevent deformation of edges of the side portion  121   a  of the tray supporting unit  120  while stably supporting the tray supporting unit  120 . 
         [0074]    In an implementation, a length t 7  of the second fixing region  238   e  of the tray fixing unit  238  may be about 50 mm or greater. Therefore, the second fixing region  238   e  may make a sufficiently long, or longer than necessary, contact area with the tray supporting unit  120 , thereby stably supporting the side portion  121   a  of the tray supporting unit  120 . 
         [0075]    By way of summation and review, a large quantity of secondary batteries may be accommodated in multiple trays, which may be accommodated in a rack. The rack accommodating the trays should secure stability against a vibration, e.g., earthquake or external shock. 
         [0076]    The embodiments provide a rack, e.g., for an energy storage system, which may help suppress vibration of trays in the rack. 
         [0077]    As described above, the energy storage system according to an embodiment may include at least one tray fixing unit inwardly protruding with respect to the guide plate formed between the side frames, the tray supporting unit inserted into the inside of the side frames from a front of the rack and along the guide plate may be vertically fixed, thereby easily preventing the tray supporting unit and the trays from vibrating in the rack. 
         [0078]    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. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope as set forth in the following claims.