Abstract:
A battery is disclosed that includes a container having a positive terminal and a negative terminal and an electrochemical cell disposed within said container, said cell having a positive electrode, a negative electrode, and a cell voltage measured across said positive and said negative electrodes of said cell. The battery further includes a housing containing electronic circuitry associated with said container, said electronic circuitry electrically connected between said electrodes of said cell and said terminals of said container to create an output voltage measured across said positive and said negative terminals of said container and wherein the container and housing substantially enclose the electrochemical cell.

Description:
This application is a national phase application depending from Patent Cooperation Treaty Patent Application Number PCT/US00/17007 filed on Jun. 20, 2000 (now abandoned), which claims the benefit of U.S. Provisional Patent Application No. 60/140,092 filed on Jun. 21, 1999 (now abandoned). 

   FIELD OF THE INVENTION 
   The present invention relates to batteries and more particularly to batteries having a housing for electronic circuitry, such as a built-in controller or an indicator for battery life. 
   BACKGROUND OF THE INVENTION 
   Consumers use batteries in portable electronic devices such as radios, compact disc players, cameras, cellular phones, electronic games, toys, pagers, and computer devices, etc. As electronic devices become faster and more complex, the devices have required more current than before. Consequently, the demands on batteries to provide greater utilization of stored energy are even greater. Co-pending applications referred to above disclose devices including a built-in controller capable of providing functions such as greater utilization of stored energy to extend the service run time of the battery, control of an electrochemical cell charge cycle by directly monitoring the electrochemical properties of that particular cell, providing a safety disconnect in the event of overheating, inverse polarity, short-circuit, over-pressure, over-charge, over-discharge or excessive hydrogen generation, and an indicator of remaining battery life to inform consumers of available stored energy. Developments such as these as well as others require electronic circuitry to be embedded inside a battery or somehow affixed to a battery. 
   However, there are many problems associated with having electronic circuitry embedded inside the battery. For example, if the electronic circuitry or electronic connections embedded in the battery are in contact with or are within the same container as the electrochemical components of the cell, these components may come into contact with the electronic circuitry or create a corrosive atmosphere that may cause damage to the electronic circuitry or electronic connections. Another problem is the electronic circuitry or electronic connections may cause electromagnetic interference (EMI) which may adversely affect the electronic devices within which the batteries are located. The electronic devices may also cause EMI which may adversely affect the electronic circuitry within the battery. Another problem associated with having electronic circuitry embedded inside the battery is that the electronic circuitry is not as sturdy as the battery cell and is easily damaged if dropped or handled roughly by a consumer. Another problem is that it is difficult to ensure reliable electronic connections from the electronic circuitry to the positive and the negative electrodes of the electrochemical cell or the positive and negative terminals of the battery, which may be required for the electronic circuitry to function. Additionally, when the electronic circuitry is embedded inside the battery container, if the electronic circuitry fails, the entire battery may also fail. This may result in unnecessary waste of an otherwise operable electrochemical cell. 
   SUMMARY OF THE INVENTION 
   The present invention provides a battery having a housing for electronic circuitry. The battery includes a container having a positive terminal and a negative terminal, an electrochemical cell and a housing containing electronic circuitry that is associated with the container. The electronic circuitry is electrically connected to the electrodes of the electrochemical cell and the terminals of the battery to create an output voltage measured across the terminals of the container. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed that the present invention will be better understood from the following description in conjunction with the accompanying drawings in which like reference numerals identify identical elements and wherein: 
       FIG. 1  is an exploded bottom perspective view of the main components of a housing according to the present invention; 
       FIG. 2  is an exploded top perspective view of the main components of a housing according to the present invention; 
       FIG. 3  is a bottom perspective view of an assembled housing of the present invention; 
       FIG. 4  is a bottom perspective view of a battery subassembly of the present invention; 
       FIG. 5  is a perspective view of an assembled battery having a housing for electronic circuitry according to the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The present invention provides a housing for electronic circuitry that is affixed to a consumer battery. The term “battery,” as used in this application, refers to a container having terminals and a single electrochemical cell, or a structure that has terminals and at least substantially contains two or more electrochemical cells (e.g., a standard 9 volt battery or a battery for a cellular telephone or laptop computer). The electrochemical cells need not be completely enclosed by a single structure if each cell has its own individual container. A portable telephone battery, for example, may contain two or more electrochemical cells that each have their own individual containers and are packaged together in a shrink-wrap plastic material that holds the individual containers together but may not completely enclose the individual containers of the cells. The term “consumer” in this application refers to a battery that is intended to be used in an electronic or electric device purchased or used by a consumer. The batteries of the present invention can be either primary or rechargeable. The term “primary” is used in this application and refers to a battery or an electrochemical cell that is intended to be discarded after its usable electrical storage capacity has been depleted (i.e., it is not intended to be recharged or otherwise reused). The terms “rechargeable” and “secondary” are used interchangeably in this application and refer to a battery or an electrochemical cell that is intended to be recharged at least once after its usable electrical storage capacity has been depleted (i.e., it is intended to be reused at least once). 
   Housing for Electronic Circuitry 
     FIG. 1  shows a bottom exploded perspective view of a particularly preferred embodiment of unassembled elements of a housing for a single-cell battery according to the instant invention.  FIG. 2  shows a top exploded perspective view of a particularly preferred embodiment of the unassembled elements of a housing for a single-cell battery according to the instant invention. As used in this application, a “housing” refers to an assembly that houses electronic circuitry. In one aspect of the present invention, the electronic circuitry except for the input and output leads may be sealed inside the housing to protect the electronic circuitry components from the potentially corrosive or damaging electrochemical components of the cell. In another aspect of the present invention, the housing may be designed such that the housing for the electronic circuitry may be separately assembled and tested. Such a housing may then be assembled together with the battery container. 
   In a preferred embodiment of the instant invention, the housing  10  has three main elements: the bezel  11 , the circuit board  12 , and the retaining ring  13 , as shown in  FIGS. 1 and 2 . 
   The bezel  11  contains a body portion  14  and an output terminal  15 . The output terminal  15  could be the output terminal of the battery or can be electrically connected to an output terminal of the battery. The body portion  14  of the bezel  11  is preferably molded of an insulating material that is impact-resistant, such as plastic, thermoplastic, polymer or polycarbonate. The impact-resistant bezel  11  provides protection for electronic circuitry  16  contained within the housing from static shock during manufacturing and mechanical shock such as dropping. The output terminal  15  is made of conductive material. In one preferred embodiment, the output terminal forms the positive terminal of the battery. Preferably, the output terminal  15  is metal and located in the center of bezel  11 . Preferably, the body portion  14  of the bezel  11  is insert-molded around the output terminal  15 . The bezel  11  preferably conforms to the shape and standard outer dimensions of a standard battery. For example, if the housing  10  is placed on the top of an AA size battery, the bezel  11  would preferably be dome-shaped, as shown in  FIG. 1 . It is also preferable that at least a portion of the body portion  14  of the bezel  11  is made of translucent or transparent material so that the circuit board  12  may be easily viewed by a consumer after the housing  10  is assembled. Preferably, the bezel  11  contains a notch  17  to aid in aligning the bezel  11 , circuit board  12  and retaining ring  13  during assembly of the housing  10 . 
   The circuit board  12  comprises the electronic circuitry  16  to be utilized within the battery  10 . Preferably, the circuit board  12  is made of Mylar or Kapton. The electronic circuitry  16  has at least three electrical contacts, a positive input contact  18 , a negative input contact  19  and an output contact  20 . Preferably, the positive input contact  18  is located in the center of the bottom of the board  12  and the negative input contact  19  is located at the bottom edge of the board  12 . The negative input contact  19  may also be used to aid in aligning the bezel  11 , circuit board  12  and retaining ring  13  during assembly. In a preferred embodiment, the output contact  20  of the circuit board  12  is a positive output contact that is electrically connected to the output terminal  15  of the bezel  11 . 
   In an alternative embodiment, the housing output terminal forms the negative terminal of the battery. In this alternative embodiment, the output contact of the circuit board may be a negative output contact that is electrically connected to the negative output terminal of the battery. The circuit board may also include additional output contacts such as a second output contact. The second output contact of the circuit board may provide, for example, a negative output contact that is electrically connected to the negative terminal of the battery if the output contact is electrically connected to the positive terminal of the battery. This may allow for a virtual ground in which the negative terminal of the battery is isolated from the negative electrode of the electrochemical cell. 
   Another output contact may be an output contact for an indicator that is external to the housing. Such an output contact may be used to control an indicator such as the ones described in co-pending application U.S. Ser. No. 09/275,495, filed on Mar. 24, 1999, entitled BATTERY HAVING A BUILT-IN INDICATOR, now U.S. Pat. No. 6,835,491 issuing on Dec. 28, 2004, naming Vladimir Gartstein and Dragan D. Nebrigic, which is incorporated by reference above. 
   Preferably, if at least a portion of the bezel  11  is translucent or transparent, the circuit board  12  may include an indicator such as an LED that a user may be able to see through the bezel  11  of the housing  10 . In a preferred embodiment, the LED indicator may have several different colors to indicate various amounts of remaining battery life. For example, the color green may be used to indicate full capacity, yellow to indicate partial capacity, and red to indicate no capacity. In another preferred embodiment, at least a portion of the bezel may be made of a flexible material such that the flexible portion of the bezel may form a “button” to activate an LED indicator. In yet another embodiment, the second output  20  contact may provide an output through which a device could receive information about the battery such as the remaining capacity of the electrochemical cell, or an output that may be used for quality assurance testing of an assembled housing or of an assembled battery. 
   The retaining ring  13  is preferably made of an insulating or dielectric material. The retaining ring  13  includes an opening  21  that allows the positive input contact  18  of the circuit board  12  to electrically connect to the positive electrode  26  of the electrochemical cell  22 . The retaining ring  13  may further include a notch  23  to aid in aligning the bezel  11 , circuit board  12  and retaining ring  13  during assembly. 
     FIG. 3  shows a preferred embodiment of an assembled housing according to the instant invention. The bezel  11 , circuit board  12 , and retaining ring  13  are preferably assembled by placing the circuit board  12  inside the bezel  11 . Preferably, the circuit board  12  is placed so that the electronic circuitry  16  is facing toward the bezel  11 . Then, the retaining ring  13  is attached to the bottom of the bezel  11 . The bezel  11 , circuit board  12 , and retaining ring  13  are preferably mechanically registered rotationally to align the bezel notch  17 , the negative terminal contact  19 , and the retaining ring notch  23 . Preferably, the bezel  11 , circuit board  12 , retaining ring  13  are then attached together. Additionally, the housing  10  may be sealed, such as by a plug seal, a welded seal or a high impact pressure seal, to provide protection against the intrusion of moisture and/or particulates into the housing  10 . 
   Because the housing  10  is assembled separately from the electrochemical cell  22 , the housing  10  may be tested for operability independent of the electrochemical cell  22 . If a housing is defective, the failed housing may be disposed of before it is combined with the electrochemical cell, thereby minimizing waste of inoperable batteries due to electronic circuitry  16  failure. Separately assembling the housing  10  also allows for cleaner assembly processes in a clean environment such as in a typical clean room used in electronic processing and assembly to prevent contamination or damage of the electronic components that might otherwise be impossible to achieve if the electronic component were assembled on a battery assembly line. Also, the assembled housing  10  may be used with various types of electrochemical cells (i.e. alkaline, zinc carbon, metal air, NiCd, lithium, lithium ion, nickel metal hydride, etc.). These technical advantages allow the instant invention to be both cost effective and easily manufacturable. 
   As shown in  FIG. 5 , the assembled housing  10  containing the electronic circuitry  16  is physically and electrically connected to an electrochemical cell  22 . The assembled housing is associated with the battery container  24 . However, the housing  10  is separate from the electrochemical cell  22 . Preferably, the housing forms or contains a separate compartment for housing the electronic circuitry apart from the electrochemical cell  22 . For example, the assembled housing may be either positioned on or positioned within the battery container  24 . The assembled housing may be either affixed by any suitable attaching means to the electrochemical cell. “Attached” or “attaching means” includes, but is not limited to spot welding, crimping, adhesive, snap fitting, and interlocking, etc. 
   As shown in  FIG. 4 , preferably, the assembled housing  10  is physically and electrically connected to a battery container by means of a subassembly  25 .  FIG. 4  shows a particularly preferred embodiment of a single-cell battery subassembly  25  of the instant invention. The battery container  24  contains a single electrochemical cell  22 . The container  24  includes all the elements necessary to insulate and protect the positive  26  and the negative  27  electrodes, separator and the electrolyte of the electrochemical cell  22  from the environment and to provide electrical energy from the electrochemical cell  22  outside of the container  22 . Thus, the container  24  in  FIGS. 4 and 5  include a side wall  28 , top  29  and bottom  30  caps, and positive  31  and negative  32  terminals that provide for electrical connection of the cell  22 . The container  24  may be made of a combination of conducting material, such as metal, and insulating material, such as plastic or a polymer. 
   In the preferred embodiment, the physical and electrical connections are achieved by a retainer  33 , a ground lead  34 , and a false bottom  35 . 
   The retainer  33  provides a socket for mounting the housing  10 . The retainer  33  is attached to the electrochemical cell  22  at the desired location of the housing  10 . In a preferred embodiment, the retainer  33  is at the top of the electrochemical cell  22 . However, the retainer  33  may be attached to the bottom or the side of the electrochemical cell  22 . Preferably, the retainer  33  is spot welded to the batter container  22 . Preferably the assembled housing  10  is attached to the retainer  33  such that the retainer ring and the retainer are affixed. Preferably, the housing  10  and retainer  33  are affixed by crimping, snapping, or adhesive. Preferably, the retainer  33  has a notch  38  to allow space for the ground lead  34  to connect the electronic circuitry to the negative ground. 
   The positive input contact  18  of the electronic circuitry is electrically connected to the positive electrode  26  of the electrochemical cell  22 . The positive output contact  20  of the electronic circuitry  16  is electrically connected to the positive terminal  31 . The negative input contact  19  is electrically connected to the negative electrode  27  of the electrochemical cell  22 . In a preferred embodiment, the output contact  20  is positive and is electrically connected to the positive terminal  15  of the battery. In an alternative embodiment of the instant invention, the output contact  20  is negative and is electrically connected to the negative terminal of the battery. The terms “electrically connected”, “electrical connection” and “electrically coupled” refer to connections or couplings that allow for continuous flow. 
   The ground lead  34  is preferably a flexible strip comprising a conductive layer and an insulating layer. The ground lead  34  has a first end  36  and a second end  37 . The conductive layer of ground lead  34  is oriented such that it faces away from the wall of the electrochemical cell  22 . Preferably, the conductive layer is made of metal foil. Preferably, the insulating material is made of a thin polymer film. Preferably, the ground lead  34  is attached to the side  28  of the battery container  24  and is folded over the top  29  and bottom  30  of the container  24 . The insulating material may have adhesive coated on it to provide a means for attaching the ground lead  34  to the battery container  24 . The first end  36  of the ground lead  34  is attached to the output  20  of the circuit board  13 . The ground lead  34  is folded through the retainer notch  38 . 
   The false bottom  35  is a metal washer. The false bottom  35  attaches the second end  36  of the ground lead  34  to the bottom of the battery container to provide a ground. Further, the false bottom  35  provides a heat sink for the electronic circuitry. 
   Preferably, the battery having a housing containing electronic circuitry of the present invention conforms to the standard outer dimensions and a standard terminal voltage of a conventional consumer battery. Thus, preferably the electrochemical cell  22  is slightly shorter than a conventional consumer battery to provide space for the housing  10  to allow the battery having a housing for circuitry that fits in and operates in standard electronic devices. It is also preferable that the slight shortening of the electrochemical cell minimizes the reduction of the volume of active electrochemistry. 
   Electronic Circuitry 
   The housing  10  of the present invention contains one or more types of electronic circuitry  16 . For example, the electronic circuitry  16  may be a controller that performs one or more of the following functions: greater utilization of stored energy to extend the service run time of the battery, control of an electrochemical cell charge cycle by directly monitoring the electrochemical properties of that particular cell, providing a safety disconnect in the event of overheating, inverse polarity, short-circuit, over-pressure, over- charge, over-discharge or excessive hydrogen generation, or an indicator of remaining battery life to inform consumers of available stored energy. 
   The electronic circuitry  16  of a battery of the present invention may perform one or more of the functions listed above. The electronic circuitry  16  of the present invention may contain one circuit that performs each of the desired functions, or may contain individual circuits that each perform one or more of the desired functions. In addition, the individual circuits may share circuitry such as sensing circuitry that may provide control signals to the individual circuits. 
   Batteries having Housing for Electronic Circuitry 
   The electrochemical cell(s)  22  of the instant of the instant invention may be either single-cell or multiple-cell. 
   The term “single-cell” refers to a battery having a single electrochemical cell packaged individually such as a standard AA, AAA, C or D type battery, or a single-cell in a multiple-cell battery (e.g., such as a standard 9 volt battery or a battery for a cellular telephone or laptop computer). 
   Multiple-cell batteries may include two or more of the same type of electrochemical cell, or include two or more different types of electrochemical cells in a hybrid battery. The multiple-cell battery of the present invention may contain electrochemical cells electrically arranged in series and/or in parallel. As used in this application, the term “hybrid battery” includes a multiple-cell battery that contains two or more voltaic cells of which at least two of those cells have different voltaic mechanisms such as photovoltaic, fuel, thermal, electrochemical, electromechanical, etc. or a different electrode, a different pair of electrodes or a different electrolyte. As used in this application term, “cell” is used to refer generally to voltaic cells used in a battery, including electrochemical cells. Also, voltaic or electro voltaic cell is used interchangeably and describes various physical mechanisms of generation of electricity including chemical. In addition, a hybrid cell may contain additional energy storage elements improving cell voltage and current discharge characteristics such as a super or ultra capacitor, high efficiency inductor, or low capacity secondary cell. The hybrid cell elements can be made to replace inactive cell construction elements such as label, seal, hollow terminals, etc. 
   In a first preferred embodiment, the electronic circuitry  16  of a single-cell battery may be electrically connected in series and/or parallel with the electrochemical cell(s) inside a housing attached to the container of a cell. In a second preferred embodiment, the electronic circuitry  16  of a multiple-cell battery may be packaged along with one or more of the individual cells as described with respect to a single-cell battery and/or may be packaged along with a combination of multiple cells such that the electronic circuitry is connected in series or in parallel with the combination of electrochemical cells. 
   Although particular versions and embodiments of the present invention have been shown and described, various modifications can be made to the battery having a housing for electronic circuitry without departing form the teachings of the present invention. The terms used in describing the invention are used in their descriptive sense and not as terms of limitation, it being intended that all equivalents thereof be included within the scope of the claims.