Patent Publication Number: US-8109389-B1

Title: Shipping container assembly for electrical storage cells

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/140,162, filed Dec. 23, 2008. 
    
    
     FIELD OF THE INVENTION 
     The invention pertains to corrugated containers for the transportation of electrical storage cells having a high sensitivity to temperature extremes, physical damage, and electrical damage. 
     BACKGROUND OF THE INVENTION 
     The use of corrugated cardboard containers for the transport of goods is well known. A wide variety of corrugated containers and associated spacing and insert materials have been developed over the years to provide inexpensive, durable and recyclable protective containers. 
     Among the many products which have been packaged and shipped in these types of containers are a wide variety of electrical storage cells and electrical storage batteries, and a number of different designs of containers for batteries and cells are found in the prior art. 
     In recent times, however, there have been substantial and important developments in battery technology. Among those developments is the invention and commercial success of the lithium ion battery. The cells of a lithium ion battery are rechargeable electrical storage cell in which lithium ions move between the anode and cathode. Typically, the lithium ion moves from the anode to the cathode during discharge and from the cathode to the anode when charging. 
     Lithium ion batteries have become popular in a wide variety of consumer electronics, due in large part to their high output to weight ratio. Lithium ion batteries also exhibit no “memory effect”, and retain a substantial portion of their charge when not in use. 
     However, lithium ion batteries and cells suffer from certain vulnerabilities, and unless appropriately used and stored, present certain dangers. In some situations, mistreatment of lithium ion batteries may cause them to burn or to explode. As a result of these hazards, the Federal Aviation Administration has expressed substantial concern about the carriage of lithium ion batteries as cargo on aircraft and has published rules that restrict the manner in which ion batteries may be transported on aircraft. 
     Lithium ion batteries are growing in popularity for use in automotive applications due to their high energy density. In automotive applications, individual lithium ion cells are often thin, planar structures that are square or rectangular in shape with electrodes which protrude from one end of the cell. For example, a typical automotive lithium ion cell may be approximately six inches wide, twelve inches long and one inch or less thick. During transportation, it is important that each individual cell be thoroughly protected above and below and around the perimeter. It is likewise important that the anode and cathode be protected from inadvertent short circuit. 
     As a result of the potential dangers associated with lithium ion batteries, it is important that such batteries be properly packaged for storage and shipment. The present invention provides substantial benefits in the art of battery transport and storage. 
     SUMMARY OF THE INVENTION 
     The present invention provides a shipping container for electrical storage cells that includes a box and a plurality of tray elements adapted to be received in the box. The box defines an interior space having an inner periphery and a height. Each tray element has an outer periphery that substantially conforms to the inner periphery of the interior space of the box, and each tray element has at least one upwardly facing recess that substantially conforms to the shape an individual electrical storage cell. 
     Each tray element may have a plurality of layers of corrugated cardboard that are bonded to one another in a vertically stacked configuration. The plurality of layers of corrugated cardboard may include a base layer that extends continuously within the outer periphery of the tray element, and the base layer may define a bottom interior surface of each recess of the tray element. The plurality of layers of corrugated cardboard may include one or more upper layers that are disposed above the base layer. The upper layers each have an aperture extending therethrough to at least partially define each recess of the tray element. 
     The base layer and the upper layers may have peripheries that are coincident with the outer periphery of the tray element. 
     The recess may includes a contoured side having a pair of terminal receiving portions that are each adapted to receive a terminal of one of the electrical storage cells. 
     The shipping container may also include a substantially planar cover panel that is disposed between the outer box and the plurality of tray elements, wherein the cover panel is adjacent to at least one of the recesses. The cover panel and the plurality of tray elements may cooperate to define a height that is substantially equal to the height of the interior space of the outer box. 
     Finally, the outer box, the plurality of tray elements and the cover panel may all be fabricated from corrugated cardboard. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The description herein makes reference to the accompanying drawings wherein like referenced numerals refer to like parts throughout several views and wherein: 
         FIG. 1  is an exploded perspective view showing a shipping container according to the present invention for transporting electrical storage cells; 
         FIG. 2  is a perspective view showing a tray element of the shipping container; 
         FIG. 3  is a partial, cross-sectional view of the tray element of  FIG. 2 ; and 
         FIG. 4  is a plan view showing a box blank from which an outer box of the shipping container assembly of the present invention is fabricated. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the drawings, the present invention will now be described in detail with reference to the preferred embodiment. 
       FIG. 1  shows a shipping container assembly  10  according to the present invention. The shipping container assembly  10  includes an outer box  12 , one or more tray elements  16  and a cover panel  20 , all of which are typically fabricated from corrugated cardboard. The outer box  12  defines an interior space  14  in which the tray elements  16  and the cover panel  20  are received. 
     The tray elements  16  and the cover panel  20  are components of a dunnage assembly that is received within the interior space  14  of the outer box  12  to support and stabilize one or more electrical storage cells  18 . When disposed within the interior space  14  of the outer box  12 , the dunnage assembly substantially conforms to a height  22  of the interior space  14 , as well as an inner periphery  24  of the interior space  14 , thus preventing movement of the dunnage assembly within the interior space  14  of the outer box  12 . 
     The electrical storage cells  18  are individual cells that can be assembled with respect to one another into an electrical storage battery (not shown). The electrical storage cells  18  are preferably lithium ion electrical storage cells. Each of the electrical storage cells  18  has a substantially rectangular body portion  17  that is typically thin and planar. A pair of terminal blocks  19  protrude from one side of the body portion  17  of each of the electrical storage cells  18  and correspond to the anode and cathode of the electrical storage cell  18 . When disposed within the shipping container assembly  10 , the electrical storage cells are insulated from contact with electrically conductive materials, are not susceptible to exposure to significant amounts of static electricity, and the terminal blocks  19  of the electrical storage cells are prevented from coming into contact with one another, as will be explained further herein. 
     As seen in  FIG. 2 , the tray element  16  is a rectangular, generally planar structure that is bounded by a generally rectangular outer periphery  25 . The outer periphery  25  may include slight deviations from a perfect rectangular shape, such as semi-circular notches  26  that allow the tray elements  16  to be removed from the outer box  12  with ease. The outer periphery  25  of each tray element  16  is shaped generally complementary in shape and size to the inner periphery  24  of the interior space  14  of the outer box  12  in order to restrain the tray elements  16  against moving with the interior space  14  of the outer box  12 . 
     In order to secure the electrical storage cells  18  within the shipping container assembly  10 , each tray element  16  includes one or more recesses  28 . The recesses  28  are upwardly facing and shallow, having a height that is complementary to the electrical storage cells  18 . For example, the recesses may have a height that is slightly greater than the height of the electrical storage cells  18 , such that vertical motion of the electrical storage cells  18  is prevented or minimized while simultaneously preventing weight that is applied to the shipping container assembly  10  from being applied to the electrical storage cells  18 . 
     The recesses  28  are also shaped complementary to the electrical storage cells  18  to prevent lateral movement of the electrical storage cells  18  within the recesses  28 . For example, each recess  28  may be bounded a substantially linear rear side  30 , a substantially linear left side  32 , a substantially linear right side  34  a contoured side  36  opposite the rear side  30 . The rear side  30 , the left side  32  and the right side  34  define a generally rectangular area, while the contoured side  36  is configured to complement the terminals  19  of the electrical storage cells  18 . 
     The contoured side  36  of each recess  28  may include one or more portions that engage a body portion  17  of each of the electrical storage cells  18 , such as a pair of shoulder portions  38  that are formed adjacent to each of the left and right sides  32 ,  34  of the recess  28  and a central portion  40  that is formed between a first terminal area  42  and a second terminal area  44 . The first and second terminal areas  42 ,  44  each receive one of the terminals  19  of the electrical storage cell  18 , thereby isolating the terminals  19  from one another and stabilizing the position of the storage cell  18  with respect to the tray element  16 . 
     In the illustrated embodiment, the tray element  16  includes two recesses  28 . However, it should be understood that tray elements could be fabricated with other numbers of recesses, such as one recess, four recesses, ten recesses, etc. 
     As shown in  FIG. 3 , each tray element  16  is a layered structure that is fabricated from corrugated cardboard. In particular, each tray element includes a base layer  46  and one or more upper layers  48 . The base layer  46  and the upper layers  48  are permanently connected to one another. For example, the base layer  46  and the upper layers  48  could be bonded together using adhesives. The outer peripheries of the base layer  46  and the upper layers  48  cooperate to define and are coincident with the outer periphery  25  of the tray element  16 . 
     The base layer  46  is substantially continuous, lacking apertures or perforations within the confines of the outer periphery  25  of the tray element  16 . The base layer  46  defines a bottom interior surface of each recess  28 . Optionally, sub-base layers (not shown) could be provided below the base layer  46  and bonded thereto to stiffen the tray element  16 . 
     One or more upper layers  48  are stacked on top of the base layer  46 . The upper layers  48  each include an opening  50  that is formed through the respective upper layer by die-cutting or other suitable means such that the opening  50  extends completely through the corrugated cardboard from which the upper layer  48  is fabricated. With the exception of the openings  50 , the upper layers  48  are substantially continuous within the confines of the outer periphery  25  of the tray element  16 , thus allowing the tray elements  16  to resist crushing in the vertical direction. The openings  50  in the upper layers  48  are aligned with one another when assembled on top of the base layer  46  to define the sides  30 ,  32 ,  34 ,  36  and the depth of each of the recesses  28  of the tray element  16 . 
     With reference again to  FIG. 1 , the outer box  12  includes a bottom panel  60 , a front panel  62 , a rear panel  64 , a right side panel  66 , and a left side panel  68  that cooperate to define the interior space  14  of the outer box  12 . The right side panel  66  and the left side panel  68  define a right side closure pocket  70  and a left side closure pocket  72 , respectively. A top panel  74  is pivotally connected to the rear panel  64  to allow closure of an open top of the interior space  14  of the outer box  12 . When the top panel  74  is pivoted to a closed position, a front closure panel  76  that is connected to the top panel  74  substantially overlies the front panel  62  and a right closure flap  78  and the left closure flap  80  that are pivotally connected to the sides of the front closure flap  76  are each received in a respective one of the right closure pocket  66  and the left closure pocket  72  that are defined by the right side panel  66  and the left side panel  68  of the outer box  12 . 
     The outer box  12  is fabricated from a box blank  82 , as shown in  FIG. 4 . The box blank  82  includes portions corresponding to, and identically numbered to, respective portions of the outer box  12 . In addition, the box blank  82  includes a plurality of right side panel portions  88  that are folded with respect to one another to provide the right side panel  66  of the outer box  12 , as well as a plurality of left side panel portions  90  that are folded with respect to one another to provide the left side panel  68  of the outer box  12 . The box blank  82  further includes a first internal bottom stiffening panel  84  and a second internal bottom stiffening panel  86  that overlie the bottom panel  60  of the outer box  12  when assembled to stiffen the bottom panel  60  of the outer box  12 . The various portions of the box blank  82  are pivotally connected to one another at fold lines  83   a  that allow the box blank  82  to be folded into the outer box  12 , and certain adjacent portions are separated from one another by cut lines  83   b  that allow for free movement of these adjacent portions with respect to one another. 
     In use, a user first constructs the outer box  12  from the box blank  82  by folding and gluing or otherwise securing the various panels to one another. The outer box  12  is then placed in an open position by pivoting the top panel  74  of the outer box  12  away from the interior space  14 . 
     Next, the user places one of the tray elements  16  into the interior space  14  of the outer box  12 . Then the electrical storage cells  18  are placed into the recesses  28  of the tray element  16 . Additional tray elements  16  and electrical storage cells  18  are placed into the interior space  14  of the outer storage box  14  in correspondence to the height  22  of the interior space  14  of the outer box  12 . 
     The cover panel  20  is placed on top of the upper most one of the tray elements  16 , adjacent to the recesses  28  thereof, such that the cover panel  20  is interposed between the tray elements  16  and the top panel  74  of the outer box  12  when the top panel  74  of the box is in a closed position. The outer box  12  is then closed by moving the top panel  74  to the closed position. 
     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, the scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.