Patent Application
20110104544
The present disclosure relates generally to hermetically sealed electronic devices and more particularly to disassembling the content of a hermetically sealed battery pack.
Electronic devices are sometimes hermetically sealed to protect against intrusion from external elements. Portable two-way radios and battery packs are examples of electronic devices which often require a hermetic seal for protection against fluids, smoke and dust. The use of a hermetic seal, particularly when dealing with battery packs, presents challenges to manufacturers seeking to provide environmentally friendly products which can be recycled. Environmental organizations have started emphasizing the need for energy products to be environmentally friendly by implementing mandatory regulations and requirements. However, hermetically sealed battery packs are very difficult to disassemble and therefore difficult to recycle. Additionally, the labor associated with dissembling hermetically sealed battery packs can make recycling costs prohibitive.
Accordingly, there is a need for an improved means of disassembling a hermetically sealed electronic device, particularly a hermetically sealed battery pack.
The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views, together with the detailed description below, are incorporated in and form part of the specification, and serve to further illustrate embodiments of concepts that include the claimed invention, and explain various principles and advantages of those embodiments.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.
Briefly there is described herein, a battery pack including a housing coupled to a cover, wherein the housing and the cover are hermetically sealed to enclose one or more batteries. In accordance with an embodiment, the cover includes an integrally molded wire within a perimeter of the cover with first and second exposed contacts. The wire is molded within the cover so as to be co-located along an edge of the housing, when the cover and housing are coupled together. The cover can be separated from the housing in response to current being applied to the first and second contacts, and pulling of the wire.
After all the components have been assembled into the housing enclosure 102, the cover 108 is deposited to cover the housing enclosure 102. The complete assembly is hermetically sealed using ultrasonic welding of the cover 108 to the housing enclosure 102. Once the welding is complete, the battery pack 100 can be deployed in a battery powered device such as a portable radio, a mobile phone, a handheld device, a laptop, a music player, a digital camera, or the like.
The front cross-sectional view 302 includes exploded views 304, 306 cut along the A-A axis of cover 108. The exploded view 304 shows an edge of the cover 108 with the high resistance wire 202 molded therein. Exploded view 306 illustrates a portion of the high resistance wire 202 which is embedded across a top portion of the cover extending into exposed contact 204, 206.
The side cross-sectional view 308 includes exploded views 310, 312, 314 cut along portions of the B-B axis of cover 108. The exploded views 310, 312 illustrate the high resistance wire 202 molded along the cover's edge. Exploded view 314 illustrates the second exposed contact 206.
The various views of
As seen in
In accordance with method 700, a high resistance wire is embedded (702) along the perimeter of a cover of a battery pack while the cover is being molded. The wire is embedded such that contacts coupled to the wire are left exposed (704) on a surface of the battery pack cover. A housing is provided to receive the battery cells (706) and the cover 108 is hermetically sealed to the housing enclosure 102 (708). Once the battery pack is sealed and deployed in an electronic device, the battery is eventually discharged and recycling may be desirable or required.
During the recycling process, a predetermined threshold of current is applied to the exposed contacts for a predetermined amount of time (710). This current flows through the high resistance wire and produces heat that will either completely melt or weaken the perimeter joint between the cover and the housing of the battery pack. The high resistance wire is then pulled from the cover (712). The cover is then removed from the battery pack enclosure (714) along the weakened joint.
Prototype testing was conducted using a housing and cover of EXL9335 material with the cover having a perimeter of 300 mm and a nichrome wire having a resistivity of 3.72 milli ohm per mm. On applying a 5 A current to the wire, the joint between the housing and the cover weakened in approx 30 seconds.
Accordingly, there has been provided a hermetically sealed enclosure which can be easily disassembled making the packaging highly desirable for recycling environments. While the method and apparatus have been described primarily in relation to sealed battery packs, hermitically sealed enclosures containing other types of devices can also benefit when formed in accordance with the embodiments of the invention.
In the foregoing specification, specific embodiments have been described. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present teachings.
The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of any or all the claims. The invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims as issued.
Moreover in this document, relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” “has”, “having,” “includes”, “including,” “contains”, “containing” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, has, includes, contains a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “comprises . . . a”, “has . . . a”, “includes . . . a”, “contains . . . a” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises, has, includes, contains the element. The terms “a” and “an” are defined as one or more unless explicitly stated otherwise herein. The terms “substantially”, “essentially”, “approximately”, “about” or any other version thereof, are defined as being close to as understood by one of ordinary skill in the art, and in one non-limiting embodiment the term is defined to be within 10%, in another embodiment within 5%, in another embodiment within 1% and in another embodiment within 0.5%. The term “coupled” as used herein is defined as connected, although not necessarily directly and not necessarily mechanically. A device or structure that is “configured” in a certain way is configured in at least that way, but may also be configured in ways that are not listed.
The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.
