Abstract:
Embodiments of the present disclosure provide methods, systems, and apparatuses related to managing a rechargeable battery in an enclosed lighting module. Other embodiments may be described and claimed.

Description:
FIELD  
       [0001]    Embodiments of the present disclosure relate to the field of lighting, and more particularly, to managing a rechargeable battery in an encased lighting module. 
       BACKGROUND  
       [0002]    Multi-chemistry rechargeable batteries are used in a variety of applications. Often the lifetimes of these batteries could include a large number of charge/discharge cycles. However, the conditions in which these batteries are deployed and the way in which they are managed could result in a large variability of battery lifetimes. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0003]    Embodiments will be readily understood by the following detailed description in conjunction with the accompanying drawings. To facilitate this description, like reference numerals designate like structural elements. Embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings. 
           [0004]      FIGS. 1   a  and  1   b  respectively illustrate exploded and assembled views of a lighting module in accordance with embodiments of this disclosure. 
           [0005]      FIG. 2  is a flowchart describing an analysis of a rechargeable battery in accordance with some embodiments. 
           [0006]      FIG. 3  illustrates a circuit diagram of components of a lighting module in accordance with some embodiments. 
           [0007]      FIG. 4  is a graph of a load line of a battery as a function of voltage and time in accordance with some embodiments. 
       
    
    
     DETAILED DESCRIPTION  
       [0008]    In the following detailed description, reference is made to the accompanying drawings which form a part hereof wherein like numerals designate like parts throughout, and in which is shown by way of illustration embodiments in which the disclosure may be practiced. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of embodiments in accordance with the present disclosure is defined by the appended claims and their equivalents. 
         [0009]    Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding embodiments of the present disclosure; however, the order of description should not be construed to imply that these operations are order dependent. 
         [0010]    For the purposes of the present disclosure, the phrase “A and/or B” means (A), (B), or (A and B). For the purposes of the present disclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C). 
         [0011]    Various components may be introduced and described in terms of an operation provided by the components. These components may include hardware, software, and/or firmware elements in order to provide the described operations. While some of these components may be shown with a level of specificity, e.g., providing discrete elements in a set arrangement, other embodiments may employ various modifications of elements/arrangements in order to provide the associated operations within the constraints/objectives of a particular embodiment. 
         [0012]    The description may use the phrases “in an embodiment,” or “in embodiments,” which may each refer to one or more of the same or different embodiments. Furthermore, the terms “comprising,” “including,” “having,” and the like, as used with respect to embodiments of the present disclosure, are synonymous. 
         [0013]      FIGS. 1   a  and  1   b  illustrate a lighting module  100  in an exploded view and an assembled view, respectively, in accordance with some embodiments. The lighting module  100  may include one or more light emitting diodes (LEDs)  104  coupled to a mounting board  108  that provides power connections to the LEDs  104 . While three LEDs  104  are shown, other embodiments may have any number of LEDs. A lens reflector  112  may be placed around a perimeter of the mounting board  108  to provide a desired optical effect. 
         [0014]    The lighting module  100  may also include a circuit board  116  that may house and interconnect various electrical components of the lighting module  100  including, but not limited to, a controller  120 . The controller  120  may be coupled to a direct current (DC) power supply interface  124  that is configured to be coupled to a rechargeable battery  128  (hereinafter “battery  128 ”), which may be a multi-chemistry rechargeable battery. In some embodiments, the battery  128  may be removably coupled to the DC power supply interface  124  in order to be easily replaced at the end of its effective life. In other embodiments, the battery  128  may be permanently coupled to the DC power supply interface  124 . In these embodiments, the entire lighting module  100  may be replaced, rather than just the battery  128 , at the end of the effective life of the battery  128 . 
         [0015]    As used herein, “removably coupled elements” are elements in which the coupling design allows a user of the device to couple/decouple the elements in the ordinary course of operation; while “permanently coupled elements” are elements in which the coupling design does not allow the user of the device to couple/decouple the elements in the ordinary course of operation. 
         [0016]    The controller  120  may also be coupled to an alternating current (AC) power supply interface  132  that is configured to be coupled to an AC power supply through, e.g., a standard lighting fixture. The AC power supply interface  132  may be an Edison screw base, of any size, as is generally shown. In other embodiments, the AC power supply interface  132  may be any other type of light bulb connector or power connector, e.g., power plug. 
         [0017]    When power is present at the AC power supply interface  132 , the controller  120  may use the AC power to power the LEDs  104  and to recharge the battery  128 , as will be described in more detail below. When AC power is not present at the AC power supply interface  132 , the controller  120  may use the DC power from the battery  128  to power the LEDs  104 . Providing backup power from the battery  128  may allow the lighting module  100  to work independent of an available AC power system. This may allow the lighting module  100  to provide a portable and/or auxiliary light source (e.g., a light source to be used when a power outage occurs in a building&#39;s electrical network). 
         [0018]    When operating as an auxiliary light source, the lighting module  100  may detect AC power in an electrical network to which it is communicatively coupled. The lighting module  100  may be communicatively coupled to the electrical network by a direct electrical connection, e.g., by a lighting fixture plugged into an outlet, or wirelessly. The lighting module  100  may include an antenna  136  and a resonant circuit in an embodiment in which it is configured to wirelessly detect AC power in a proximally-disposed electrical network as is described in co-pending application titled LIGHTING MODULE WITH WIRELESS ALTERNATING CURRENT DETECTION SYSTEM filed contemporaneously with the present application. The specification of said application is hereby incorporated in its entirety except for those sections, if any, that are inconsistent with the present specification. 
         [0019]    The lighting module  100  may also include a state switch  140  coupled to the controller  120  through the circuit board  116 . The state switch  140  may be operated to change between various operating states of the lighting module  100 . For example, in one embodiment the lighting module  100  may have two states. In a first state, the lighting module  100  may function as an auxiliary light. That is, the LEDs  104  are activated when AC power is not detected in an electrical network to which the lighting module  100  is communicatively coupled. In a second state, the LEDs  104  may be activated, regardless of the presence/absence of AC power in the electrical network. In other embodiments, additional and/or alternative states may be provided. 
         [0020]    The components of the lighting module  100 , including the battery  128  when it is coupled to the DC power supply interface  124 , may be disposed within an enclosure defined, at least in part, by a bulb-shaped, light passable body  144  (hereinafter “body  144 ”) and a base  148 , which may include the AC power supply interface  132 . The lighting module  100  may include a temperature sensing device  152  that is coupled to the controller  120  to determine a temperature inside of the enclosure. The temperature sensing device  152  is shown as being disposed on the circuit board  116 ; however, in other embodiments it may be disposed in other locations within the enclosure. Furthermore, in other embodiments, additional temperature sensing devices may be placed throughout the enclosure. For example, one temperature sensing device may be placed near the battery  128  while another temperature sensing device may be placed near the LEDs  104 . 
         [0021]    Disposing the components of the lighting module  100  within the enclosure, as shown, facilitates use of the lighting module  100  as an interchangeable replacement for conventional light bulbs. However, the confinements of the enclosure may restrict heat dissipation and complicate various charge/discharge analyses of the battery  128 . Performing these analyses improperly in such a high-ambient temperature environment may result in early failure of the battery  128  and/or lighting module  100 . Accordingly, embodiments of the disclosure described herein present various management techniques and/or analyses that the controller  120  may employ in order to efficiently manage the battery  128  to increase its useful life and more accurately determine and communicate its status. 
         [0022]    The controller  120  may be coupled with memory  156 , which may be volatile and/or non-volatile memory that stores data that may relate to the operation of the battery  128 . The data may include impedance, temperature, current, electric reflectivity, number of cycles, and total coulomb-metric data for the life of the battery  128 , etc. The controller  120  may acquire this data from a programming device through a programming interface  160 , from one or more sensors of the lighting module  100 , e.g., the temperature sensing device  152 , and/or from monitoring/testing the operation of the battery  128  itself. The controller  120  may use this data to determine a state of charge and/or a predicted cycle life of the battery  128  as will be described. 
         [0023]    The controller  120  may control an indicator LED  164  in a manner to communicate information about the state of charge and/or predicted cycle life of the battery  128 . For example, the indicator LED  164  may indicate when the battery  128  will no longer provide a prescribed operating regime for the lighting module  100 . The LED  164  may flash to indicate the lighting module  100  and battery  128  should be inspected. The indicator LED  164  may be set to a steady state to indicate that lighting module  100  and battery  128  are functioning properly. In other embodiments, other indication methods, which may include more than one indicator LED, may be employed. For example, in some embodiments, the indicator LED  164  may include an array of LEDs to communicate a level of the charge of the battery  128 . 
         [0024]      FIG. 2  is a flowchart showing analysis  200  of the battery  128  in accordance with some embodiments. At block  204 , the controller  120  may determine an electrical reflectivity of the battery  128 . The determination of the electrical reflectivity may be described with additional reference to  FIG. 3 , which illustrates a circuit diagram  300  of some of the components of the lighting module  100 , and  FIG. 4 , which is a graph of a load line  400  of the battery  128  as a function of voltage (V) and time (T), in accordance with some embodiments. 
         [0025]    At time T 0 , the controller  120  may couple a load, e.g., a load resistor  304 , to the battery  128  by closing a switch  308 . This may result in the load line  400  dropping from an initial voltage V 0  to an intermediate voltage V 1 . At time T 1 , the controller  120  may release the load by opening the switch  308 . This may result in the load line  400  recovering until it is at a final voltage V 2  at time T 2 . The electrical reflectivity of the battery  128  may then be determined by measuring the recovery, e.g., (V 2 −V 1 )/(T 2 −T 1 ). 
         [0026]    Referring again to  FIG. 2 , the controller  120  may determine an impedance of the battery  128  at block  208 . When the battery  128  is new it may have a full charge approximately equal to its rated capacity. The charge of the battery  128  may be substantially inversely proportional to its impedance. Thus, when new and fully charged, the battery  128  may have a very low impedance. As the battery  128  experiences charge/discharge cycles over the period of its normal use, its effective capacity at full charge may decrease. Accordingly, the full charge impedance may experience a corresponding increase over the life of the battery  128 . The controller  120  may determine the impedance of the battery  128  at a certain charge state, e.g., a full charge state. 
         [0027]    Having determined the impedance and/or the electrical reflectivity of the battery  128 , the controller may determine a state of charge and/or predicted cycle life at block  212 . In some embodiments, the controller  120  may determine a state of charge of the battery  128  based at least in part on the determined electrical reflectivity, and may determine the predicted cycle life based at least in part on the determined impedance. 
         [0028]    In some embodiments, the controller  120  may determine the state of charge and/or predicted cycle life of the battery  128  by using the determined electrical reflectivity/impedance as indices to reference values in one or more lookup tables stored in memory  156 . 
         [0029]    As the temperature within the enclosure will affect the impedance of the battery  128 , temperature volatility may have a significant impact on the predicted cycle life determination. Accordingly in some embodiments, the controller  120  may determine the impedance and/or determine the predicted cycle life based at least in part on a determined temperature. 
         [0030]    In addition to performing the analyses of the battery  128  described above, the controller may also regulate the recharging cycles of the battery  128  in order to enhance its longevity. The battery  128  may have a separator that is placed between its anode and cathode. If the battery  128  is exposed to excessive temperatures, this separator may break down and damage the battery  128  and/or the lighting module  100 . Recharging the battery  128 , with or without simultaneous operation of the LEDs  104 , while it is within the enclosure may accelerate the separator breakdown if not properly managed. Accordingly, the controller  120  may also control the charging of the battery  128  in light of the temperature of the enclosure. 
         [0031]    In some embodiments, the controller  120  may determine that the temperature is within one of a plurality of temperature ranges. Each temperature range may be associated with its own recharging duty cycle. Consider, for example, a recharging schedule that provide a 100% recharging duty cycle for a low temperature range; a 60% recharging duty cycle for a medium temperature range; and a 20% recharging duty cycle for a high temperature range. Controlling the recharging of the battery  128  according to this recharging schedule may preserve the integrity of the battery  128  and/or lighting module  100 . The controller  120  may access this recharging schedule through the one or more lookup tables stored in memory  156 . 
         [0032]    Although certain embodiments have been illustrated and described herein for purposes of description of the preferred embodiment, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent embodiments or implementations calculated to achieve the same purposes may be substituted for the embodiments shown and described without departing from the scope of the present disclosure. Similarly, memory devices of the present disclosure may be employed in host devices having other architectures. This application is intended to cover any adaptations or variations of the embodiments discussed herein. Therefore, it is manifestly intended that embodiments in accordance with the present disclosure be limited only by the claims and the equivalents thereof.