Patent Publication Number: US-11639789-B2

Title: Portable light and keyed rechargeable USB battery

Description:
This application claims the benefit and priority of U.S. Patent Application No. 63/136,900 entitled “PORTABLE LIGHT AND KEYED RECHARGEABLE USB BATTERY” that was filed on Jan. 13, 2021, which is hereby incorporated herein by reference in its entirety. 
    
    
     The present invention relates to a rechargeable portable light, and, in particular, to a rechargeable portable light including a rechargeable power source. The present invention also relates to a rechargeable power source with keying to the portable light. 
     Traditional rechargeable lights could be charged by being placed into a receptacle of a charging device wherein the light and the charging device had compatibly located electrical contacts of a charging interface or the rechargeable battery thereof could be charged by removing it from the light and placing it into a receptacle of a battery charging device. Some charging devices had plural charging receptacles, e.g., one for the light and another for the battery therefrom. 
     More recently, some rechargeable lights were outfitted with an externally accessible charging connector, e.g., a standard connector such as a coaxial connector or a USB connector mounted in the body of the light, to which a compatible connector of an external power source charging device or of a cable connected to an external power source could be connected for charging a rechargeable battery via conductors and/or other circuitry inside the light while the rechargeable battery was disposed inside the light. 
     With the more recent advent of rechargeable lithium batteries which require certain protective circuitry to protect the battery from overcharging and/or over discharging, at least a part of such battery protection circuitry began to be packaged with the lithium battery in a common package or container, e.g., an AA size container. Since this requires an electronic circuit board in the battery package, a charging connector accessible from outside the battery started to be provided, so that the battery could be removed from the light and connected to a charging source, e.g., to an external power pack or a computer via a coaxial or USB connector outside of the light, thereby providing convenience for the user. 
     For example, a type 18650 rechargeable lithium battery and the like have a cylindrical case, typically like a 1.5 VDC size AA battery, with electrically positive (+) and negative (−) terminals on respective opposite ends thereof, and may have a USB charging connector in the side thereof. Many if not all batteries of this sort have symmetrical cases, e.g., cylindrical cases, and so there is and cannot be a known orientation of the battery when placed in the light. 
     At around the same time, manufacturers of portable lights began to provide charging connectors on the portable light itself, so that an external charging source could be connected to the portable light, e.g., by a coaxial or a USB connector, for charging the battery via the circuitry of the light while the battery is inside the portable light. That, however, results in additional complexity and cost for lights that have such connectors, but it does enable the battery to be charged when it is in the light as well as when it is outside the light. 
     Applicant believes there may be a need for a portable light that can receive a rechargeable source of electrical power having a charging connector that will be in a known predetermined orientation relative to the light. Applicant believes that providing a rechargeable power source having a keying feature that will align with a complementary keying feature of a light will avoid that problem. Thus, the power source and the light are respectively oriented into a known predetermined orientation by the keying features so that an opening in the body of the portable light is aligned to permit directly connecting a charging connector from an external power source through the opening in the light body and into the charging connector of the rechargeable source of electrical power whilst the rechargeable source of electrical power is inside the light. This would allow the elimination of the charging connector and related elements that are part of the light itself in conventional lights, thereby to likely reduce the complexity and cost thereof. 
     In addition, it is also believed that it would be advantageous if portable lights having different configurations and/or uses are configured to operate using rechargeable sources of electrical power having a common configuration including a charging connector and keying features, whereby sources of electrical power of a predetermined configuration could be utilized in and interchanged between and among many different lighting products. 
     Accordingly, a portable light may comprise: a light body having an internal cavity configured to receive a rechargeable power source, having a keying feature, and having an opening through an exterior wall in a predetermined location relative to the keying feature; a light source; a rechargeable power source having a charging connector and a keying feature in predetermined locations that when the keying feature thereof engages the keying feature of the internal cavity, the charging connector thereof is aligned with the opening through the external wall; and an electrical switch for energizing the light source. Thus an external source of charging power can be connected through the opening directly to the charging connector of the rechargeable power source for recharging the rechargeable power source. 
     Further, a portable light may comprise: a light body having an internal cavity configured to receive a rechargeable battery, having a keying feature, and having an opening through an exterior wall in a predetermined location relative to the keying feature; a light source; a rechargeable battery having a charging connector and a keying feature in predetermined locations that when the keying feature thereof engages the keying feature of the internal cavity, the charging connector thereof is aligned with the opening through the external wall; and an electrical switch for energizing the light source. Thus an external source of charging power can be connected through the opening directly to the charging connector of the rechargeable battery for recharging the rechargeable battery. 
     In addition, a rechargeable power source for a portable light may comprise: a power source case including a rechargeable electrical cell therein; one or more electrical terminals on the power source case coupled to the electrical cell; a charging connector in a side of the power source case and coupled for charging the electrical cell; the power source case having a keying feature in a known predetermined location relative to the charging connector such that when the rechargeable power source is placed into a portable light with the keying feature of the rechargeable power source engaging a complementary keying feature of the portable light, the charging connector of the rechargeable power source will be aligned with an opening through an external wall of the portable light. 
     In summarizing the arrangements described and/or claimed herein, a selection of concepts and/or elements and/or steps that are described in the detailed description herein may be made or simplified. Any summary is not intended to identify key features, elements and/or steps, or essential features, elements and/or steps, relating to the claimed subject matter, and so are not intended to be limiting and should not be construed to be limiting of or defining of the scope and breadth of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       The detailed description of the preferred embodiment(s) will be more easily and better understood when read in conjunction with the FIGURES of the Drawing which include: 
         FIG.  1    is a perspective view of an example embodiment of a hand holdable portable light having an opening for connecting an external charging device directly to a charging connector of a rechargeable power source inside the example light,  FIGS.  1 A and  1 B  are side views of the example embodiment of such portable light, and  FIGS.  1 C and  1 D  are cross-sectional views thereof; 
         FIGS.  2 A through  2 H  are two perspective views, four side views and two end views, respectively, of an example rechargeable source of electrical power suitable for use with the portable light of  FIGS.  1 - 1 D ; 
         FIGS.  3 A through  3 H  are two perspective views, four side views and two end views, respectively, of an example rechargeable source of electrical power suitable for use with the portable light of  FIGS.  1 - 1 D ; 
         FIG.  4    is a perspective view of an example embodiment of a portable head light having an opening for connecting an external charging device directly to a charging connector inside the example light,  FIGS.  4 A,  4 B and  4 C  are side views of the example embodiment of such portable head light, and  FIGS.  4 D and  4 E  are cross-sectional views thereof; and 
         FIG.  5    is a perspective view of an example embodiment of another hand holdable portable light having one or more openings for connecting an external charging device directly to a charging connector of one or more power sources inside the example light,  FIGS.  5 A,  5 B,  5 C and  5 D  are side views thereof and  FIGS.  5 E,  5 F,  5 G and  5 H  are cross-sectional views thereof. 
     
    
    
     In the Drawing, where an element or feature is shown in more than one drawing figure, the same alphanumeric designation may be used to designate such element or feature in each figure, and where a closely related or modified element is shown in a figure, the same alphanumerical designation may be primed or designated “a” or “b” or the like to designate the modified element or feature. Similar elements or features may be designated by like alphanumeric designations in different figures of the Drawing and with similar nomenclature in the specification. As is common, the various features of the drawing are not to scale, the dimensions of the various features may be arbitrarily expanded or reduced for clarity, and any value stated in any Figure is by way of example only. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
       FIG.  1    is a perspective view of an example embodiment of a hand holdable portable light  100  having an opening  150  for connecting an external charging device directly to a charging connector of a rechargeable power source inside the example light,  FIGS.  1 A and  1 B  are side views of the example embodiment of such portable light  100 , and  FIGS.  1 C and  1 D  are cross-sectional views thereof. Example portable light  100 , e.g., a light configured to be holdable in a user&#39;s hand, is generally cylindrical in shape and has a cylindrical body  120  with a light head  130  including a light source at a forward end thereof and a tail cap  140  at a rearward end thereof. Lights with such configuration are commonly referred to as flashlights, although that term is often more broadly used. Light  100  has a charging port  150  whereat an external source of electrical power, e.g., an external charging device, may be connected for recharging the source of electrical power  200  of light  100 . 
     Example light body  120  is tubular and has a cavity  122  therein in which a source of electrical power  200  is disposed for providing electrical power to energize the light source  132 , e.g., a light emitting diode  132 , of light head  130 . Light body  120  is configured to receive light head  130  on one end thereof and to receive tail cap  140  on the other end thereof. Light body  120  has an opening  124  through an exterior wall thereof relating to charging port  150 . Optionally, but preferably, a slidable collar  160  or cover  160  may be provided for sliding along light body  120  for covering and uncovering charging port  150 , as indicated by the double ended arrow aside cover  160 . Optionally, a clip  128  may be provided on light body  120 . 
     Example light head  130  includes a head housing  130 H that attaches to light body  120  and that contains the light source. Light source  132  is preferably a light emitting diode (LED)  136  that produces light when energized. Housing  130 H also includes an optical element  134  disposed in front of LED  132  for forming the light produced thereby into a beam having desired characteristics. Optical element  134  may be a shaped reflector or may be a solid optical element, e.g., a totally internally reflective (TIR) optical element. A lens  136  covers the front face of light head  130  to reduce entry of dirt, debris and moisture into light head  130  and light  100 . 
     Example light head  130  may have two parts, e.g., a main housing  130 H and a lens retaining ring  130 R retaining optical element  134  and lens  136  therein. Typically, one or more electronic circuit boards  170  are disposed in light  100 , e.g., rearwardly in head housing  130  and/or forwardly in light body  120 , as may be convenient, for controlling the application of electrical power from the electrical power source  200  thereof to light source  132  for energizing light source  132  to produce light in response to an electrical switch. 
     Example tail cap  140  includes a housing  142  in which is disposed an electrical switch  144  that can be actuated to open and close one or more electrical contacts thereof for controlling the operation of portable light  100 , e.g., for energizing and de-energizing light source  132  thereof. A flexible actuator  146 , e.g., a boot  146 , may be provided to reduce entry of dirt, debris and moisture into tail cap  140  and light  100 . Pressing and releasing flexible actuator  146  causes the actuation and de-actuation of electrical switch  144 . 
     Example tail cap housing  142  may have plural parts, e.g., a rearward part  142 R supporting boot  146  and a forward part  142 F that supports rearward part  142 R and attaches tail cap  140  to light body  120 . Electrical switch  144  is disposed within housing parts  142 F and  142 R. 
     Example source of electrical power  200  includes an externally accessible charging port  250  to which an external source of charging power may be connected for charging and recharging power source  200  when it is in a device, e.g., portable light  100 , not in a device. Typically, one example power source  200  includes a rechargeable battery  200 , e.g., a rechargeable lithium battery  200 , that has a symmetrical shape, e.g., a cylindrical shape, as do other common batteries. Because a symmetrical source of electrical power can be placed into a compatible cavity in different radial orientations, if a charging port  150  is provided thereon, then the charging port  150  thereof can be different radial positions relative to the cavity  122 , i.e. the housing into which it is placed, and so would not necessarily align with the opening  124  in the light body  120 . 
     Importantly, portable light  100  and power source  200  differ from other lights and power sources in that light  100  and power source  200  each have an asymmetrical feature, e.g., a keying feature, that is complementary to that of the other so that power source  200  may only be fully placed into cavity  124  of light  100  when their respective keying features are aligned and engaged. The respective keying features are complementary, e.g., one may be a recess while the other is a projection of similar size and shape, such that the projection keying feature fits into the recess keying feature. This can occur only when the power source  200  is in a predetermined radial orientation whereat the projection keying feature is aligned with the recess keying feature. 
     Keying feature  126  of light  100  is provided for cavity  122  of housing  120  thereof in a predetermined known position relative to opening  124  through housing  120 , e.g., diametrically opposite opening  124 , which also may be described as being 180 degrees radially around therefrom. Keying feature  230  of power source  200  is provided on housing  210  thereof in a predetermined known position relative to charging port  250  thereof, e.g., diametrically opposite charging port  250  which also may be described as being 180 degrees radially around therefrom. 
     Because each of the respective keying features  126 ,  230  are in complementary predetermined known positions relative to opening  124  and charging port  250 , respectively, when keying features  126 ,  230  are engaged, power source  200  is in a known predetermined position in cavity  122  and light body  120  whereat charging port  250  of power source  200  is adjacent to and is aligned with opening  120  of light body  120 , thereby to define an external charging port  150  of light  100 . As a result, charging port  150  provides direct access to power source charging port  250  through opening  124  in light body  120  of light  100 , whereby an external power source may be directly connected to power source  200 , i.e. to charging port  250  thereof, through opening  124 . 
     Even when power source  200  may include a symmetrical internal energy cell  270 , e.g., a battery cell  270  or other cylindrical cell  270 , case  210  or housing  210  of power source  200  has one or more asymmetrical external keying features  230  by which power source  200  may only be disposed in light body  120  in the one orientation in which charging port  250  thereof aligns with opening  124  to define the external charging port  150  of light  100 . 
       FIGS.  2 A through  2 H  are two perspective views, four side views and two end views, respectively, of an example rechargeable source of electrical power  200  suitable for use with the portable light  100  of  FIGS.  1 - 1 D ; and  FIGS.  3 A through  3 H  are two perspective views, four side views and two end views, respectively, of an example rechargeable source of electrical power  200  suitable for use with the portable light  100  of  FIGS.  1 - 1 D . 
     Source of electrical power  200 , or power source  200 , e.g., often a rechargeable battery, e.g., preferably a rechargeable lithium battery according to present technology, and may include one or more electrical cells therein. Power source  200  typically includes an outer case  210 , which may be the case of the power cell therein or a separate housing  210 , and optionally a sleeve  212  there around which in the instance of a plural cell power source, may retain the plural cells in a desired physical configuration, e.g., end to end. 
     Power source  200  may have one or more external electrical contacts or terminals  240  for making electrical connections from the energy cell therein to external circuitry, e.g., to a load, such as a light source  132 . In the example embodiment of  FIGS.  2 A- 2 H , two electrical terminals  240  are provided at one end of power source  200 , and may be configured, e.g., recessed, to reduce the likelihood that accidental electrical contact may be made to or between them. Therein, and optionally, one of terminals  240  at the forward end of power source  200  may be electrically connected to a terminal  240  at the opposite or rearward end thereof, e.g., for which an electrically conductive housing  210  may provide an electrical connection. In the example embodiment of  FIGS.  3 A- 3 H , two electrical terminals  240  are provided at opposite ends of power source  200 , and their separation tends to reduce the likelihood that accidental electrical contact may be made between them. 
     Typically, outer case  210  may be of an insulating material, e.g., a plastic sleeve, or may be of an electrical conductive material, e.g., a metal. In the example illustrated, power source  200  is generally cylindrical, as is common for such cells, except for keying feature  230 . Outer sleeve  212  is typically an insulating sleeve to cover housing  210 , particularly where housing  210  is an electrically conductive case  210 . Typically, where outer case  210  is electrically conductive, it is connected to one of terminals  240 ,  240  and may be exposed at the end of power source  200  that is distal from the end thereof having terminals  240 , e.g., by an opening in or area not covered by insulating sleeve  212  so that the distal end may be utilized as a terminal thereof. 
     Power source  200  has a keying feature  230 , e.g., a squared off recess  230  or a curved recess  230 , that makes power source  200  radially asymmetric. The keying feature of the rechargeable power source is, e.g., a recess defining a concave surface proximate an end of the rechargeable power source; or a recess defining two planar surfaces having an intersection that is transverse to a longer dimension of the rechargeable power source and is proximate an end of the rechargeable power source. Typically, but not necessarily, keying feature  230  is at the end of power source  200  having electrical terminals  240  which often, if not usually, is the end that is placed first into a light or other device to connect with electrical contacts at the far end of the cavity of the light or other device that it powers. 
     The keying feature  230  illustrated in  FIGS.  2 A- 2 F  may be, e.g., defined as the shape of an intersection of a cylinder whose axis is transverse to a longitudinal axis of generally cylindrical power source  200  and is offset therefrom in a direction away from its charging port  250 . The axis of the transverse cylinder may be outside the volume of power source  200 . Thus charging port  250  and keying feature  230  are in known predetermined locations of cylindrical source  200 , and the shape of keying feature  230  may be, e.g., a part of the surface of the transverse cylinder. In that example, those known predetermined locations include keying feature  230  and charging port  250  being radially opposite each other, e.g., radially 180° apart, and charging port  250  being in a known predetermined axial location by being a known predetermined axial distance from the end of source  200  at which keying feature  230  and terminals  240  are located. 
     Further, terminals  240  illustrated in  FIGS.  2 A- 2 F  are also at respective known predetermined locations, e.g., being spaced apart on that end of power source  200  by a known predetermined distance and being on opposite sides thereof, e.g., one terminal  240  being located or spaced away from a first side of the longitudinal axis and the other terminal  240  being located or spaced away from an opposite of second side thereof, wherein a line between the centers of terminals  240  is parallel to and offset from the axis of the transverse cylinder defining the shape of keying feature  230 . The shape of terminals  240  may be circular or rectangular or any other desired regular or irregular shape, and may be recessed as illustrated or may not be recessed. 
     The keying feature  230  illustrated in  FIGS.  3 A- 3 F  may be, e.g., defined as the shape of an intersection of a rectangular solid whose axis is transverse to a longitudinal axis of generally cylindrical power source  200  and is offset therefrom in a direction away from its charging port  250 . The axis of the transverse rectangular solid may be outside the volume of power source  200 . Thus charging port  250  and keying feature  230  are in known predetermined locations of cylindrical source  200 , and the shape of keying feature  230  may be, e.g., a part of the surface of the transverse rectangular solid, e.g., two flat surfaces whose intersection (i.e. a line) is transverse to the longitudinal axis of power source  200 . In that example, those known predetermined locations include keying feature  230  and charging port  250  being radially opposite each other, e.g., radially 180° apart, and charging port  250  being in a known predetermined axial location by being a known predetermined axial distance from the end of power source  200  at which keying feature  230  and terminals  240  are located. 
     Further, terminals  240  illustrated in  FIGS.  3 A- 3 F  are also at respective known predetermined locations, e.g., being spaced apart on opposite ends of power source  200  by a known predetermined distance, e.g., the length of power source  200 . Those terminals  240  typically would be centered on each end of power source  200 , e.g., on the longitudinal axis thereof, wherein a line between the centers of terminals  240  is parallel to and coaxial with from the longitudinal axis thereof. The shape of terminals  240  may be circular or rectangular or any other desired regular or irregular shape, and may be flush or projecting or recessed. 
     Power source  200  has a charging port  250  whereat an external charging device may be connected to recharge power source  200 . In a preferred embodiment, charging port  250  includes an electrical connector, e.g., a coaxial connector  250  or a USB connector, e.g., a USB connector, mini-USB connector, a micro-USB connector, a USB-C connector, FireWire connector, a Lightning connector, or another commonly used electrical connector. 
     Charging port  250  is located on power source  200  in a known predetermined spatial relationship relative to keying feature  230  thereof, e.g., recess  230 , so that controlling the location of recess  230  in light  100  determines the orientation of power source  200  therein and thus the location of charging port  250  in light  100 . For example, the relative radial position of recess  230  and charging port  250  and the axial distance of charging port  250  from the end of power source  200  are predetermined. In a preferred embodiment, charging port  250  is 180° radially around from keying feature  230  and is a known axial distance from the end of power source  200 , and light body  120  has a keying feature  126  near an end of its internal cavity  122  that is complementary to keying feature  230  and has an opening  124  which is 180° radially around therefrom and the known axial distance therefrom, so that charging port  250  is constrained by complementary keying features  230 ,  126  to be aligned with opening  124 , whereby an external charging device can be directly connected to charging port  250  of power source  200  through the opening  124 . 
     Rechargeable lithium batteries typically require electrical circuitry to limit the charging and discharging of the lithium cell(s) therein to safe levels, and such circuitry is often provided on an electronic circuit board  252  that is packaged internally to a lithium battery, e.g., power source  200 . Typically, it is convenient that electrical connector  254  of charging port  250  be mounted on such circuit board  252  adjacent to an opening in housing  210  so as to be accessible to and radially directly connectable with a compatible connector of an external charging source. Typically, case or housing  210  may include a cylindrical main part which contains the rechargeable electrical, power or energy cell  270 , e.g., a rechargeable lithium electrical cell  270  or battery  270 , and a cap  210 C therefor which may enclose, e.g., circuit board  252  and which may have one or more recessed terminals  240  thereon or one or more recessed openings for one or more terminals  240 , e.g., two recessed openings for the example two terminals  240  illustrated in  FIGS.  2 A- 2 F . 
     Where keying feature  230  of power source  200  is, e.g., a concave curved recess  230 , then complementary keying feature  126  in cavity  122  is, e.g., a convex curved projection  126  of similar compatible size and shape. Similarly, where keying feature  230  of power source  200  is, e.g., a rectangular recess  230 , then complementary keying feature  126  in cavity  122  is, e.g., a rectangular projection  126  of similar compatible size and shape. Alternatively, keying features  230  and  126  may be of any suitable shape and size, and/or keying feature  230  may be a projection and keying feature  126  may be a recess. 
       FIG.  4    is a perspective view of an example embodiment of a portable head light  300  having an opening  350 ,  324  for connecting an external charging device directly to a charging connector  250  inside the example light  300 ,  FIGS.  4 A,  4 B and  4 C  are side views of the example embodiment of such portable light  300 , and  FIGS.  4 D and  4 E  are cross-sectional views thereof. Example portable light  300 , e.g., a so-called head light that is configured to be wearable on a user&#39;s head or head wear, ed a hat or helmet, is generally T-shaped and has a T-shaped light body  320  including a transverse cylindrical body part  320 T having an extension  320 E extending transversely therefrom, e.g., typically centrally. A light head  330  includes a light source  332  at a forward end thereof. An end cap  340  attaches at one end of the transverse part  320 T of light body  320  and a cover  380  attaches at the opposite end thereof. Light  300  has a charging port  350  whereat an external source of electrical power, e.g., an external charging device, may be connected for recharging the source of electrical power  200  of light  300 . 
     Example light body  320  has a tubular part  320 T that has a cavity  322  therein in which a source of electrical power  200  is disposed for providing electrical power to energize the light source  332 , e.g., a light emitting diode  332 , of light head  330 . Light body  320  is configured to receive light head  330  on the end of the body extension  320 E and to receive end cap  340  and cover  380  on the opposite ends of transverse part  320 T thereof. Light body  320  has an opening  324  relating to charging port  350  through which access to charging port  250  of power source  200  is available. 
     Typically, a bracket  328  may be provided on light body  320  to which a head band or head strap may be attached for enabling light  300  to be worn by a user, e.g., on the user&#39;s head. Bracket  328  typically has a saddle  328 S that is curved, and that optionally has a pad or cushion  328 P, for the user&#39;s comfort. One or more clips  328 C, e.g., two curved or circular clips  328 C, extend from the saddle of bracket  328  for grasping the cylindrical part  320 C or light body  320  to retain bracket  328  thereon. Preferably, curved clips  328 C provide a movable grasping of cylindrical part  320 C so that bracket  328  may be rotated around light body  320 , and an optional detent  320 D, e.g., an arc or projections on light body  320 , engage a flexible detent  328 D of bracket  328  so that bracket  328  tends to remain in a position relative to light body  320  to which a user has moved it. 
     Example light head  330  includes a head housing  330 H that also serves as a lens retainer ring  330 R that attaches to light body  320  and that contains the light source. Light source  332  is preferably a light emitting diode (LED)  332  that produces light when energized. Housing  330 H also includes an optical element  334  disposed in front of LED  332  for forming the light produced thereby into a beam having desired characteristics. Optical element  334  may be a shaped reflector or may be a solid optical element, e.g., a totally internally reflective (TIR) optical element. A lens  336  covers the front face of light head  330  to reduce entry of dirt, debris and moisture into light head  330  and light  300 . 
     Typically, one or more electronic circuit boards  376  may be disposed in light  300 , e.g., rearwardly in head housing  330  and/or at or near one or both ends of the transverse part of light body  320 , as may be convenient, for controlling the application of electrical power from the source  200  thereof to light source  332  for energizing light source  332  to produce light in response to an electrical switch. In the illustrated embodiment, circuit board  376  supports the one or more contacts  374  which make contact with the terminals  420  of power source  200 . 
     Example end cap  340  includes a housing  342  in which is disposed an electrical switch  344  that can be actuated to open and close one or more electrical contacts thereof for controlling the operation of portable light  300 , e.g., for energizing and de-energizing light source  332  thereof. End cap  340  housing  342  has a threaded end  342 T that attaches end cap  340  to light body  320  and electrical switch  344  is disposed within end cap housing  342 . A flexible actuator  346 , e.g., a boot  346 , may be provided to reduce entry of dirt, debris and moisture into end cap  340  and light  300 . Pressing and releasing flexible actuator  346  causes the actuation and de-actuation of electrical switch  344 . 
     Specifically, electrical switch  344  is disposed in end housing part  342 E thereof to which is attached threaded housing part  342 T to retain boot  346  and switch  344  and their associated parts in end cap  340 . Threaded housing part  342 T threadingly engages threads on light body  320  for removably attaching end cap  340  thereto. Internal cavity  322  is accessed by removing end cap  340  from light body  320  thereby enabling a power source  200  to be placed into cavity  322  and removed from cavity  322 , and attaching end cap  340  to light body  320  to retain a power source  200  therein. 
     Example light body  320  may have plural parts, e.g., a transverse part  320 T which may include plural sub-parts and light head extension  320 E. In the illustrated example light body  320 , light head extension  320 E has a cylindrical bore into which two opposing end parts of transverse part  320 T are disposed to define light body  320 . Optionally, but preferably, clips  328 C of bracket  328  are rings  328 C through which the two opposing end parts of transverse part  320 T are respectively disposed so that bracket  328  is rotatably retained on light body  320 . 
     Example end cap or cover  380  threads onto an end of transverse housing part  320 T when light  300  is assembled and is not removed by a user. Cover  380  retains an internal interface member  372  in housing part  320 T which includes engaging feature  326 , or keying feature  326 . A circuit board  376  is included therein which supports one or more electrical contacts  374  that make electrical connections to terminals  240  of an power source  200  disposed in internal cavity  322 . Internal member  372  is in turn keyed or otherwise oriented with respect to the interior of transverse part  320 T so that engaging feature  326  is disposed in the known predetermined relationship with respect to opening  324  of charging port  350  of light  300 , e.g., 180° around therefrom. 
     Optionally, but preferably, a cover  360  may be provided on light body  320  for covering and uncovering charging port  350 . In the illustrated embodiment, cover  380  on one end of light body  320  includes a housing part  382 H that is attached to light body  320  and a slidable part  382 S that slides toward and away from light body  320  on housing part  382 H, as indicated by a double-ended arrow, thereby serving as a cover  360  for charging port  350  of light  300 . Moving cover  360  (housing part  382 S) away from light body  320  exposes charging port  350  (including opening  324  through which access to charging port  250  of power source  200  is available) and moving cover  360  (housing part  382 S) toward light body  320  covers charging port  350 . 
     Example source of electrical power  200  includes an externally accessible charging port  250  to which an external source of charging power may be connected for charging and recharging power source  200  when it is in a device, e.g., portable light  300 , or not in a device. Typically, one example power source  200  includes a rechargeable battery  200 , e.g., a rechargeable lithium battery  200 , that has a symmetrical shape, e.g., a cylindrical shape, as do other common batteries. Because a symmetrical source of electrical power can be placed into a compatible cavity in different radial orientations, if a charging port  350  is provided thereon, then the charging port  350  thereof can be different radial positions relative to the cavity  322 , i.e. the housing into which it is placed, and so would not necessarily align with the opening  324  in the light body  320 . 
     Importantly, portable light  300  and power source  200  differ from other lights and power sources in that light  300  and power source  200  each have an asymmetrical feature, e.g., a keying feature, that is complementary to that of the other so that power source  200  may only be fully placed into cavity  324  of light  300  when their respective keying features are aligned and engaged. The respective keying features are complementary, e.g., one may be a recess while the other is a projection of similar size and shape, such that the projection keying feature fits into the recess keying feature. This can occur only when the power source  200  is in a predetermined radial orientation whereat the projection keying feature is aligned with the recess keying feature. 
     Keying feature  326  of light  300  is provided for cavity  322  of housing  320  thereof in a predetermined known position relative to opening  324  through housing  320 , e.g., diametrically opposite opening  324 , which also may be described as being 180 degrees radially around therefrom. Keying feature  230  of power source  200  is provided on housing  210  thereof in a predetermined known position relative to charging port  250  thereof, e.g., diametrically opposite charging port  250  which also may be described as being 180 degrees radially around therefrom. 
     Because each of the respective keying features  326 ,  230  are in complementary predetermined known positions relative to opening  324  and charging port  250 , respectively, when keying features  326 ,  230  are engaged, power source  200  is in a known predetermined position in cavity  322  and light body  320  whereat charging port  250  of power source  200  is adjacent to and is aligned with opening  324  of light body  320 , thereby to define an external charging port  350  of light  300 . As a result, charging port  350  provides direct access to power source charging port  250  through opening  324  in light body  320  of light  300 , whereby an external power source may be directly connected to power source  200 , i.e. to charging port  250  thereof, through opening  324 . 
     Even when power source  200  may include a symmetrical internal energy cell  270 , e.g., a battery cell  270  or other cylindrical cell  270 , case  210  or housing  210  of power source  200  has one or more asymmetrical external keying features  230  by which power source  200  may only be disposed in light body  320  in the one orientation in which charging port  250  thereof aligns with opening  324  to define the external charging port  350  of light  300 . 
       FIG.  5    is a perspective view of an example embodiment of another hand holdable portable light  400  having one or more openings  424  for connecting an external charging device directly to a charging connector  250  of one or more power sources  200  inside the example light,  FIGS.  5 A,  5 B,  5 C and  5 D  are side views thereof and  FIGS.  5 E,  5 F,  5 G and  5 H  are cross-sectional views thereof. Example hand held portable light  400 , e.g., a light configured to be holdable in a user&#39;s hand, is generally rectangular in shape and may have some rounded sides and corners. Light  400  has a light body  420  with a light head  430  including a light source  432  at a forward end thereof and a tail cap  480  or cover  480  at a rearward end thereof. Lights with such configuration may be referred to as flashlights, although that term is often more broadly used. Light  400  has one or more charging ports  450  on a flat side thereof whereat an external source of electrical power, e.g., an external charging device, may be connected for recharging the on or more sources of electrical power  200  of light  400 . 
     Example light body  420  is generally rectangular in shape and has a cavity  422  therein in which one or more sources of electrical power  200  are disposed for providing electrical power to energize the light source  432 , e.g., one or more light emitting diodes  432 , of light head  430 . Light body  420  is configured to have a light head  430  on one end thereof and to receive tail cap or cover  480  on the other end thereof. Light body  420  has one or more openings  424  relating to and aligned with the charging ports  450  of the one or more power sources  200  therein. Optionally, but preferably, a cover  460  is provided on light body  420  for covering and uncovering charging port  450 . Optionally, a clip  428  may be provided on light body  420 . 
     Example light head  430  includes a head housing  430 H that attaches to light body  420  and that contains the light source  432 . Light source  432  is preferably one or more light emitting diodes (LED)  436  that produce light when energized. Front housing  430 H also includes an optical element  434  disposed in front of the one or more LEDs  432  for forming the light produced thereby into a beam having desired characteristics. Optical element  434  may be a shaped reflector or may be a solid optical element, e.g., a totally internally reflective (TIR) optical element, that is configured for the number and configuration of light sources  432  provided. A lens  436  covers the front face of light head  430  to reduce entry of dirt, debris and moisture into light head  430  and light  400 , and is retained thereon by lens retainer  430 R. 
     Example light head  430  may have two parts, e.g., a main housing  430 H and a lens retainer  430 R that retains optical element  434  and lens  436  therein. Typically, one or more electronic circuit boards  470  are disposed in light  400 , e.g., rearwardly in head housing  430  and/or in light body  420 , as may be convenient, for controlling the application of electrical power from the electrical power source  200  thereof to light source  432  for energizing light source  432  to produce light in response to an electrical switch  440 . 
     Example light head  430  includes a housing  430 H in which is disposed an electrical switch  444  that can be actuated to open and close one or more electrical contacts thereof for controlling the operation of portable light  400 , e.g., for energizing and de-energizing light source  432  thereof. A flexible actuator  446 , e.g., a boot  446 , may be provided to reduce entry of dirt, debris and moisture into light  400 . Pressing and releasing flexible actuator  446  causes the actuation and de-actuation of electrical switch  440 . Optionally a cover  442  may be provided to prevent actuation of switch  440 . Example cover  442  is slidable forwardly to uncover switch  440  so that it can be actuated and is slidable rearwardly to cover switch  440  so that it cannot be actuated. 
     The example housing  430  may have plural features, e.g., a transverse bore in which are disposed actuation elements of switch  440  and a cavity in which are disposed electrical switch  444  and one or more circuit boards  448 ,  478 . Flexible actuator or boot  446  is disposed at an end of the bore at the surface of light head  430  whereat it can be pressed by a user and a plunger  445  movable in the bore is adjacent the inner side of flexible boot  446 . Movement of plunger  445  is coupled to electrical switch  444  by actuator parts  447 , e.g., a spring and cups  447 . Electrical switch  444  is disposed on circuit board  448  within head housing parts  430 H. 
     Each example source of electrical power  200  includes an externally accessible charging port  250  to which an external source of charging power may be connected for charging and recharging power source  200  when it is in a device, e.g., portable light  400 , and not in a device, as described. In the example light  400 , two example power sources  200  including rechargeable batteries  200 , e.g., a rechargeable lithium battery  200 , are provided in a side by side arrangement within cavity  422  of light body  420 . that has a symmetrical shape, e.g., a cylindrical shape, as do other common batteries. Because a symmetrical source of electrical power can be placed into a compatible cavity  422  in different radial orientations, if a charging port  450  is provided thereon, then the charging port thereof can be different radial positions relative to the cavity  422 , i.e. the housing into which it is placed, and so would not necessarily align with the opening  424  in the light body  420 . 
     Importantly, portable light  400  and power source  200  differ from other lights and power sources in that light  400  and each of the one or more power source  200  each have an asymmetrical feature, e.g., a keying feature, that is complementary to that of the other so that power source  200  may only be fully placed into cavity  424  of light  400  when their respective keying features are aligned and engaged. The respective keying features are complementary, e.g., one may be a recess while the other is a projection of similar size and shape, such that the projection keying feature fits into the recess keying feature. This can occur only when the power source  200  is in a predetermined radial orientation whereat the projection keying feature is aligned with the recess keying feature. 
     Respective keying features  426  in cavity  422  of light  400  are provided for each electrical power source  200  thereof that can be disposed in cavity  422  of housing  420  thereof, each in a predetermined known position relative to a respective opening  424  through housing  420 , e.g., diametrically opposite opening  424 , which also may be described as being 180 degrees radially around therefrom. Keying feature  230  of each power source  200  is provided on housing  210  thereof in a predetermined known position relative to charging port  250  thereof, e.g., diametrically opposite charging port  250  which also may be described as being 180 degrees radially around therefrom. 
     Because each of the respective keying features  426 ,  230  are in complementary predetermined known positions relative to a respective opening  424  and charging port  250 , respectively, when keying features  426 ,  230  are engaged, each power source  200  is in a known predetermined position in cavity  422  and light body  420  whereat charging port  250  of power source  200  is adjacent to and is aligned with its respective opening  424  of light body  420 , thereby to define an external charging port  450  of light  400 . As a result, each charging port  450  provides direct access to a respective power source charging port  250  through a respective opening  424  in light body  420  of light  400 , whereby an external power source may be directly connected to power source  200 , i.e. to charging port  250  thereof, through opening  424 . 
     Even when power source  200  may include a symmetrical internal energy cell  270 , e.g., a battery cell  270  or other cylindrical cell  270 , case  210  or housing  210  of power source  200  has one or more asymmetrical external keying features  230  by which power source  200  may only be disposed in light body  420  in the one orientation in which charging port  250  thereof aligns with opening  424  to define the externally accessible charging port  450  of light  400 . 
     Cover  480 , e.g., a battery cover  480 , at the rear end of light body  420  is removable so as to permit the one or more power sources  200  to be placed into and removed from cavity  422  of light body  420 . Respective springs  482  on an inner side of cover  480  bias power sources  200  to move forwardly and into contact with contacts  474 , e.g., battery contacts  474 . Respective battery contacts  474  are provided for electrically connecting respective terminals  240  of power sources  200  with circuit board  470  which supports contacts  474 . Cover  480  maybe retained on light body  420  by one or more fasteners  484  and have a seal or gasket  486 . 
     In the illustrated example light  400 , port cover  460  for charging port  450  comprises two covers  460 , e.g., covers  460 A and  460 B, that are flexibly connected to light body  420  via a cover part or structure  462 . Where port cover  460  has two covers  460 A,  460 B, the two covers  460 A,  460 B are flexibly connected to cover structure  422 , typically at opposing sides thereof. Port cover  460  is retained on light body  420  by a fastener  464  that passes through cover part  462  thereof into light body  420 . Preferably, port cover  460  is a single part of a flexible material, e.g., a rubber or silicone or other elastomer, having a shape configured to be thinner and more flexible where covers  460 A,  460 B join center part  462  so that covers  460 A,  460 B can be rotated outwardly and away from light body  420  to respectively expose charging ports  450  and in the opposite direction towards light body  420  to respectively cover charging ports  450 . Preferably, each cover  460 A,  460 B has a flexible rim which is of complementary shape to opening  424 , whereby it is removably retained in a respective opening  424  and preferably provides a seal thereof that reduces the entry of moisture, dirt and debris into light  400  via port  450 . 
     In a typical embodiment, various housings and parts thereof, e.g., parts  210 ,  120 ,  220 ,  320 ,  328 ,  420 ,  130 ,  330 ,  430 ,  140 ,  340 ,  440 ,  442 ,  160 ,  260 ,  360 ,  460 ,  480  and the like may be a reinforced nylon, engineered nylon, engineered nylon, nylon 6, nylon 66, polyamide, polyamide 66, reinforced polyamide, reinforced polyamide 66, acrylonitrile butadiene styrene (ABS), polycarbonate, polyethylene, polypropylene, polycarbonate, polyester-polycarbonate blend, ABS polycarbonate blend, or other suitable plastic material, or of a cast, molded, forged, or machined metal. Where a part provides heat sinking, e.g., in light head  130 ,  330 ,  430 , such may include a relatively highly thermally conductive material such as aluminum, brass, copper, magnesium, cast metal, and/or a plastic filled with thermally conductive particles, e.g., a thermally conductive reinforced nylon, engineered nylon, acrylonitrile butadiene styrene (ABS), polycarbonate, polyethylene, polypropylene, or other suitable thermally conductive plastic material, e.g., a plastic that includes (is filled with) thermally conductive particles, flakes, strands or other thermally conductive material, as well as other materials having suitable strength and thermal conductivity. Metal parts, such as clips  128 ,  428 , fasteners  464 , and springs may be of any suitable metal, e.g., aluminum, steel, spring steel, metal wires, brass, bronze, magnesium, beryllium copper, cast metal, and the like. Resilient and/or flexible parts, such as flexible boots  146 ,  346 ,  446 , covers  460  and seals, may be of any suitable flexible and/or resilient material, e.g., rubber, neoprene rubber, elastomers, thermoplastic elastomers (TPEs), silicones, urethanes, MONOPRENE® rubber, nylon-bondable SANTOPRENE® rubber, HERCUPRENE rubber, NYLABOND® TPE over-molding material, AuroraFlex™ TPE over-molding material, and other suitable materials. 
     A rechargeable portable light  100 ,  300 ,  400  may comprise: a light body  120 ,  320 ,  420  having at least one exterior wall for defining at least a part of an internal cavity configured to receive a rechargeable power source  200 , wherein the internal cavity has a keying feature and has an opening through the exterior wall that is in a predetermined location relative to the keying feature of the internal cavity; a light source  132 ,  332 ,  432  supported by the light body  120 ,  320 ,  420  for producing light when energized; a rechargeable power source  200  having a charging connector in a side thereof and having a keying feature, wherein the keying feature thereof is in a predetermined location relative to the charging connector such that when the rechargeable power source  200  is placed into the internal cavity of the light body  120 ,  320 ,  420  with the keying feature of the rechargeable power source  200  engaging the keying feature of the internal cavity the charging connector of the rechargeable power source  200  is aligned with the opening through the exterior wall of the light body  120 ,  320 ,  420 ; and an electrical switch for selectively coupling the rechargeable power source  200  to the light source  132 ,  332 ,  432  for energizing the light source  132 ,  332 ,  432  to produce light; whereby a connector of an external source of charging power can be connected through the opening through the light body  120 ,  320 ,  420  directly to the charging connector of the rechargeable power source  200  for recharging the rechargeable power source  200 . The light body  120 ,  320 ,  420  may include a cover for the internal cavity that is openable for placing the rechargeable power source  200  into the internal cavity of the light body  120 ,  320 ,  420  and for removing the rechargeable power source  200  from the internal cavity thereof. The keying feature of the internal cavity may be at an end of the internal cavity that is distal from the cover for the internal cavity. The keying feature of the internal cavity may be one of a projection and a recess, and the keying feature of the rechargeable power source  200  may be the other of a recess and a projection. The keying feature of the internal cavity may be proximate one of more electrical contacts in the internal cavity that make electrical connection to corresponding one or more electrical terminals of the rechargeable power source  200  when the rechargeable power source  200  is in the internal cavity with its keying feature engaging the keying feature of the internal cavity. The keying feature of the internal cavity may be: a projection defining a convex surface proximate an end of the internal cavity; or a projection defining two planar surfaces having an intersection that is transverse to the internal cavity; or a recess defining a concave surface proximate an end of the internal cavity; or a recess defining two planar surfaces having an intersection that is transverse to the internal cavity and is proximate an end of the internal cavity. The keying feature of the rechargeable power source  200  may be: a projection defining a convex surface proximate an end of the rechargeable power source; or a projection defining two planar surfaces having an intersection that is transverse to the rechargeable power source; or a recess defining a concave surface proximate an end of the rechargeable power source; or a recess defining two planar surfaces having an intersection that is transverse to and is proximate an end of the rechargeable power source. The one or more electrical terminals of the rechargeable power source  200  may include: a central terminal and a concentric annular terminal on an end of the rechargeable power source  200 ; or two side by side terminals on the end of the rechargeable power source  200 . The rechargeable portable light may further comprise a cover movable relative to the exterior wall of the light body  120 ,  320 ,  420  for covering and uncovering the opening through the exterior wall of the light body  120 ,  320 ,  420 . The rechargeable portable light may further comprise a cover movable toward and away from the exterior wall of the light body  120 ,  320 ,  420  for covering and uncovering the opening through the exterior wall of the light body  120 ,  320 ,  420 . The rechargeable portable light may further comprise an annular collar slidable along the exterior wall of the light body  120 ,  320 ,  420  for covering and uncovering the opening through the exterior wall of the light body  120 ,  320 ,  420 . The rechargeable power source  200  may include a rechargeable battery; or the rechargeable power source  200  may include a rechargeable lithium battery. The charging connector of the rechargeable power source  200  may include: a coaxial connector, a USB connector, a mini-USB connector, a micro-USB connector, a USB-C connector, a FireWire connector, a Lightning connector, or a combination thereof. The keying feature  230  of the rechargeable power source  200  may be: recess defining a concave surface proximate an end of the rechargeable power source  200 ; or a recess defining a concave part of a cylindrical surface proximate an end of the rechargeable power source  200 ; or a recess defining two planar surfaces having an intersection that is transverse to a longer dimension of the rechargeable power source  200  and is proximate an end of the rechargeable power source  200 . The rechargeable power source  200  may have a cylindrical case, wherein at least one of the one or more electrical terminals is on a circular terminal end of the power source case, wherein the charging connector is at a predetermined radial location and is a predetermined distance from the terminal end of the power source case. The keying feature of the rechargeable power source  200  may be at a location that is about 180° radially from the charging connector and is proximate the circular terminal end. The power source case may include a cylindrical main part which contains the rechargeable electrical cell and a cap therefor, wherein: the cap encloses an electrical circuit board; or the cap has one or more recessed openings for the one or more electrical terminals; or; the cap encloses an electrical circuit board and has one or more recessed openings for the one or more electrical terminals. The rechargeable power source  200  may be cylindrical having one or more terminals at a terminal end thereof, wherein the keying feature of the rechargeable power source  200  is: a recess defining a concave surface proximate the terminal end of the rechargeable power source  200 ; or a recess defining a concave part of a cylindrical surface proximate the terminal end of the rechargeable power source; or a recess defining two planar surfaces having an intersection that is transverse to a longer dimension of the rechargeable power source  200  and is proximate the terminal end of the rechargeable power source  200 . 
     A rechargeable portable light  100 ,  300 ,  400  may comprise: a light body  120 ,  320 ,  420  having at least one exterior wall for defining at least a part of an internal cavity configured to receive a rechargeable battery  200 , wherein the internal cavity has a keying feature and has an opening through the exterior wall that is in a predetermined location relative to the keying feature of the internal cavity; a light source  132 ,  332 ,  432  supported by the light body  120 ,  320 ,  420  for producing light when energized; a rechargeable battery  200  having a charging connector in a side thereof and having a keying feature, wherein the keying feature thereof is in a predetermined location relative to the charging connector such that when the rechargeable battery  200  is placed into the internal cavity of the light body  120 ,  320 ,  420  with the keying feature of the rechargeable battery  200  engaging the keying feature of the internal cavity the charging connector of the rechargeable battery  200  is aligned with the opening through the exterior wall of the light body  120 ,  320 ,  420 ; and an electrical switch for selectively coupling the rechargeable battery  200  to the light source  132 ,  332 ,  432  for energizing the light source  132 ,  332 ,  432  to produce light; whereby a connector of an external source of charging power can be connected through the opening through the light body  120 ,  320 ,  420  directly to the charging connector of the rechargeable battery  200  for recharging the rechargeable battery  200 . The light body  120 ,  320 ,  420  may include a cover for the internal cavity that is openable for placing the rechargeable battery  200  into the internal cavity of the light body  120 ,  320 ,  420  and for removing the rechargeable battery  200  from the internal cavity thereof. The keying feature of the internal cavity may be at an end of the internal cavity that is distal from the cover for the internal cavity. The keying feature of the internal cavity may be one of a projection and a recess, and the keying feature of the rechargeable battery  200  may be the other of a recess and a projection. The keying feature of the internal cavity may be proximate one of more electrical contacts in the internal cavity that make electrical connection to corresponding one or more electrical terminals of the rechargeable battery  200  when the rechargeable battery  200  is in the internal cavity with its keying feature engaging the keying feature of the internal cavity. The keying feature of the internal cavity may be: a projection defining a convex surface proximate an end of the internal cavity; or a projection defining two planar surfaces having an intersection that is transverse to the internal cavity; or a recess defining a concave surface proximate an end of the internal cavity; or a recess defining two planar surfaces having an intersection that is transverse to the internal cavity and is proximate an end of the internal cavity. The keying feature of the rechargeable battery may be: a projection defining a convex surface proximate an end of the rechargeable battery; or a projection defining two planar surfaces having an intersection that is transverse to the rechargeable battery; or a recess defining a concave surface proximate an end of the rechargeable battery; or a recess defining two planar surfaces having an intersection that is transverse to and is proximate an end of the rechargeable battery. The one or more electrical terminals of the rechargeable battery  200  may include: a central terminal and a concentric annular terminal on an end of the rechargeable battery  200 ; or two side by side terminals on the end of the rechargeable battery  200 . The rechargeable portable light may further comprise a cover movable relative to the exterior wall of the light body  120 ,  320 ,  420  for covering and uncovering the opening through the exterior wall of the light body  120 ,  320 ,  420 . The rechargeable portable light may further comprise an annular collar slidable along the exterior wall of the light body  120 ,  320 ,  420  for covering and uncovering the opening through the exterior wall of the light body  120 ,  320 ,  420 . The charging connector of the rechargeable battery  200  may include: a coaxial connector, a USB connector, a mini-USB connector, a micro-USB connector, a USB-C connector, a FireWire connector, a Lightning connector, or a combination thereof. The keying feature of the rechargeable battery  200  may be: a recess defining a concave surface proximate an end of the rechargeable battery  200 ; or a recess defining a concave part of a cylindrical surface proximate an end of the rechargeable battery; or a recess defining two planar surfaces having an intersection that is transverse to a longer dimension of the rechargeable battery  200  and is proximate an end of the rechargeable battery  200 . The rechargeable battery may have a cylindrical case, wherein at least one of the one or more electrical terminals is on a circular terminal end of the battery case, wherein the charging connector is at a predetermined radial location and is a predetermined distance from the terminal end of the battery case. The keying feature of the rechargeable battery may be at a location that is about 180° radially from the charging connector and is proximate the circular terminal end. The battery case may include a cylindrical main part which contains the rechargeable electrical cell and a cap therefor, wherein: the cap encloses an electrical circuit board; or the cap has one or more recessed openings for the one or more electrical terminals; or the cap encloses an electrical circuit board and has one or more recessed openings for the one or more electrical terminals. The rechargeable battery  200  may be cylindrical having one or more terminals at a terminal end thereof, wherein the keying feature of the rechargeable battery  200  is: a recess defining a concave surface proximate the terminal end of the rechargeable battery  200 ; or a recess defining a concave part of a cylindrical surface proximate the terminal end of the rechargeable battery; or a recess defining two planar surfaces having an intersection that is transverse to a longer dimension of the rechargeable battery  200  and is proximate the terminal end of the rechargeable battery  200 . 
     A rechargeable power source  200  for a portable light  100  may comprise: a power source case  210  including a rechargeable electrical cell  270  therein; one or more electrical terminals  240  on an end of the power source case  210  and/or on opposing ends of the power source case  210 , wherein the one or more electrical terminals  240  are coupled to the rechargeable electrical cell; a charging connector  250  in an opening in a side of the power source case  210  and coupled to the rechargeable electrical cell  270  for charging the electrical cell; the power source case  210  having a keying feature  230 , wherein the keying feature thereof is in a known predetermined location relative to the charging connector  250  such that when the rechargeable power source is placed into a portable light with the keying feature of the rechargeable power source engaging a complementary keying feature of the portable light, the charging connector of the rechargeable power source will be aligned with an opening through an exterior wall of the portable light. The rechargeable power source  200  wherein the power source case  210  is cylindrical, wherein at least one of the one or more electrical terminals  240  is on a circular terminal end of the power source case, wherein the charging connector is at a predetermined radial location and is a predetermined distance from the terminal end of the power source case. The keying feature  230  thereof may be at a location that is about 180° radially from the charging connector and is proximate the circular terminal end. The keying feature thereof may be one of a projection and a recess. The keying feature thereof may be proximate the one or more electrical terminals  240  that make electrical connection to corresponding one or more electrical terminals of the portable light when the rechargeable power source  200  is in the portable light with its keying feature  230  engaging the keying feature of the portable light. The one or more electrical terminals  240  thereof may include: two terminals  240 , each one on an opposite end of the rechargeable power source; or a central terminal  240  and a concentric annular terminal  240  on one end of the rechargeable power source; or two side by side terminals  240  on one end of the rechargeable power source. The rechargeable power source  200  may include: a rechargeable battery or a rechargeable lithium battery. The charging connector  250  thereof may include: a coaxial connector, a USB connector, a mini-USB connector, a micro-USB connector, a USB-C connector, a FireWire connector, a Lightning connector, or a combination thereof. The keying feature  230  thereof may be: a recess defining a concave surface proximate an end of the rechargeable power source; or a recess defining a concave part of a cylindrical surface proximate an end of the rechargeable power source; or a recess defining two planar surfaces having an intersection that is transverse to a longer dimension of the rechargeable power source and is proximate an end of the rechargeable power source. The rechargeable power source  200  may be cylindrical having one or more terminals  240  at a terminal end thereof, and wherein the keying feature thereof is: a recess defining a concave surface proximate the terminal end of the rechargeable power source; or a recess defining a concave part of a cylindrical surface proximate the terminal end of the rechargeable power source; or a recess defining two planar surfaces having an intersection that is transverse to a longer dimension of the rechargeable power source and is proximate the terminal end of the rechargeable power source. The power source case  210  may include a cylindrical main part which contains the rechargeable electrical cell  270  and a cap therefor, wherein: the cap encloses an electrical circuit board; or the cap has one or more recessed openings for the one or more electrical terminals; or; the cap encloses an electrical circuit board and has one or more recessed openings for the one or more electrical terminals. The rechargeable power source may be in combination with a portable light which may comprise: a light body configured to receive the rechargeable power source and having a keying feature that is complementary to the keying feature of the rechargeable power source, the light body having an opening through an exterior wall thereof that is in the same known predetermined location relative to the keying feature of the light body as is the charging connector of the rechargeable power source relative to the keying feature thereof; whereby the charging connector of the rechargeable power source is aligned with an opening through the exterior wall of the light body; a light source for producing light when energized; and an electrical switch for selectively energizing the light source to produce light. 
     A rechargeable power source  200  for a portable light  100 ,  300 ,  400  may comprise: a power source case  210  including an electrical cell  270  therein; one or more electrical terminals  240  on an end of the power source case  210  and/or on opposing ends of the power source case, wherein the one or more electrical terminals  240  are coupled to the electrical cell  270 ; a charging connector  250 ,  254  in an opening in a side of the power source case  210  and coupled to the electrical cell  270  for charging the electrical cell; the power source case  210  having a keying feature  230 , wherein the keying feature  230  thereof is in a known predetermined location relative to the charging connector  250 ,  254  such that when the rechargeable power source is placed into an internal cavity of a portable light with the keying feature of the rechargeable power source engaging a complementary keying feature of the internal cavity of the portable light, the charging connector of the rechargeable power source will be aligned with an opening through an exterior wall of the portable light. The rechargeable power source  200  in combination with a portable light  100 ,  300 ,  400  which may comprise: a light body  120 ,  320 ,  420  having at least one exterior wall for defining at least a part of an internal cavity  122 ,  322 ,  422  configured to receive the rechargeable power source  200 , wherein the internal cavity has a keying feature  126 ,  326 ,  426  that is complementary to the keying feature  230  of the rechargeable power source  200 , the light body having an opening  124 ,  324 ,  424  through the exterior wall thereof that is in the same known predetermined location relative to the keying feature of the light body as is the charging connector of the rechargeable power source relative to the keying feature thereof; wherein when the rechargeable power source  200  is placed into the internal cavity of the light body  120 ,  320 ,  420  with the keying feature of the rechargeable power source engaging the keying feature of the internal cavity of the light body the charging connector of the rechargeable power source is aligned with the opening through the exterior wall of the light body; a light source  132 ,  332 ,  432  supported by the light body for producing light when energized; and an electrical switch  140 ,  340 ,  440  for selectively coupling the rechargeable power source to the light source for energizing the light source to produce light; whereby a connector of an external source of charging power can be connected through the opening through the exterior wall of the light body directly to the charging connector of the rechargeable power source for recharging the rechargeable power source. 
     As used herein, the term “about” means that dimensions, sizes, formulations, parameters, shapes and other quantities and characteristics are not and need not be exact, but may be approximate and/or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art. In general, a dimension, size, formulation, parameter, shape or other quantity or characteristic is “about” or “approximate” whether or not expressly stated to be such. It is noted that embodiments of very different sizes, shapes and dimensions may employ the described arrangements. 
     Although terms such as “front,” “back,” “rear,” “side,” “end,” “top,” “bottom,” “up,” “down,” “left,” “right,” “upward,” “downward,” “forward,” “backward,” “under” and/or “over,” “vertical,” “horizontal,” and the like may be used herein as a convenience in describing one or more embodiments and/or uses of the present arrangement, the articles described may be positioned in any desired orientation and/or may be utilized in any desired position and/or orientation. Such terms of position and/or orientation should be understood as being for convenience only, and not as limiting of the invention as claimed. 
     As used herein, the term “plurality” means plural, two or greater in number of whatever the term pertains to, i.e. or more than one. Further, the term “predetermined” as used herein means determined in advance or before hand with respect to whatever the term pertains to. Either term may be used with respect to a physical object or thing and with respect to an intangible thing, e.g., a signal or data, and the like. 
     As used herein, the term “and/or” encompasses both the conjunctive and the disjunctive cases, so that a phrase in the form “A and/or B” encompasses “A” or “B” or “A and B” and a phrase in the form “A, B and/or C” includes “A,” “B,” “C,” “A and B,” “A and C,” “B and C,” and “A and B and C.” In addition, the term “at least one of” one or more elements is intended to include one of any one of the elements, more than one of any of the elements, and two or more of the elements up to and including all of the elements, and so, e.g., phrases in the form “at least one of A, B and C” include “A,” “B,” “C,” “A and B,” “A and C,” “B and C,” and “A and B and C.” 
     As used herein, the term “predetermined” means determined in advance and while that may include a fixed value, position, condition and/or limit, predetermined is not limited to a fixed value, position, condition and/or limit. A predetermined value, position, condition and/or limit may change or otherwise vary over time, over a sequence and/or over a randomized series of values, positions, conditions and/or limits. 
     A fastener as used herein may include any fastener or other fastening device that may be suitable for the described use, including threaded fasteners, e.g., bolts, screws and driven fasteners, as well as pins, rivets, nails, spikes, barbed fasteners, clips, clamps, nuts, speed nuts, cap nuts, acorn nuts, and the like. Where it is apparent that a fastener would be removable in the usual use of the example embodiment described herein, then removable fasteners would be preferred in such instances. A fastener may also include, where appropriate, other forms of fastening such as a formed head, e.g., a peened or heat formed head, a weld, e.g., a heat weld or ultrasonic weld, a braze, and adhesive, and the like. 
     While various operations, steps and/or elements of a process or method or operation may be described in an order or sequence, the operations, steps and/or elements do not need to be performed in that order or sequence, or in any particular order or sequence, unless expressly stated to require a particular order or sequence. 
     The terms power source and battery are used herein to refer to an electro-chemical device comprising one or more electro-chemical cells and/or fuel cells, and so a battery may include a single cell or plural cells, whether as individual units or as a packaged unit. A battery is one example of a type of an electrical power source suitable for a portable or other device. Such devices could include power sources including, but not limited to, fuel cells, super capacitors, solar cells, and the like. Any of the foregoing may be intended for a single use or for being rechargeable or for both, and/or plural ones thereof may be combined into a battery pack or battery assembly. 
     Various embodiments of a rechargeable source of electrical power that can be charged while inside a portable light include, e.g., a battery that may have one or more rechargeable battery cells, e.g., one, two, three, four, or five or more battery cells, as may be deemed suitable for any particular device. Such an example battery may employ various types and kinds of rechargeable battery chemistry types, e.g., nickel-metal-hydride (NiMH) or lithium-ion (Li-Ion) battery type, of a suitable number of cells and cell capacity for providing a desired operating time and/or lifetime for a particular device. Examples thereof may include a one to four cell NiMH battery typically producing about 1.2 to 4.8 volts in operation, or a one to two cell Lithium battery typically producing about 3.5 to 7 volts in operation, it being noted that the voltages produced thereby will be higher when charging and when approaching full charge and will be lower in discharge, particularly when providing higher current and when reaching a low level of charge, e.g., becoming discharged. For example, a typical lithium cell is charged to about 4.1-4.2 volts and includes circuitry to cut off discharge at about 3.0 volts to protect the cell. 
     While the present invention has been described in terms of the foregoing example embodiments, variations within the scope and spirit of the present invention as defined by the claims following will be apparent to those skilled in the art. For example, while the examples described herein are typically smaller lights that a user can carry in a hand or on his body, the invention may be employed in many different types and kinds of lights and other devices, whether or not easily portable, that include a rechargeable source of electrical power that has a charging port, e.g., an externally accessible charging connector, which can be accessed from outside the light or device for connecting an external source of charging power directly to the charging port of the source of electrical power while it is in the light or device. 
     While certain illustrated embodiments of example covers  160 ,  360 ,  460  for charging port  150 ,  350 ,  450  are illustrated as being captive on or attached to the light, e.g., attached by a fastener or encircling a part of the light to slide thereon, the cover may be separate from and not connected to the light or may be attached thereto by a lanyard or a tether or another retainer. For example, either of portable lights  100 ,  300  could employ a snap-in, snap-out cover similar to that described in relation to light  400 . 
     While the example source of electrical power  200  is illustrated as having a generally symmetrical shape, e.g., a generally cylindrical shape, except for the keying feature  230  thereof, the power source  200  could be of any shape that would permit it to be placed into the light  100 ,  300 ,  400  in more than one orientation except for the keying action of its keying feature  230  with a complementary keying feature  126 ,  326 ,  426  of the light. For example, power source  200  could have a circular, rectangular, square, hexagonal, octagonal or other cross-sectional shape not defining a unique radial orientation except for the keying feature  230  thereof. 
     The terms engaging feature and keying feature are used interchangeably herein in relation to the features  126 ,  326 ,  426 ,  230  that determine the position of the power source  200  in the cavity  122 ,  322 ,  422  of the light body  120 ,  320 ,  420  such that the charging port or charging connector  250  of the power source  200  is aligned with the opening in the light body  120 ,  320 ,  420 . A keying feature may be concave or convex, a recess or a projection, or any combination thereof. 
     Electrical power source  200  may have more than one charging port  250 , e.g., each including an electrical connector of a different type. In such case, a light or device employing such power source  200  would have at least one opening in a predetermined location and of a size and shape that is compatible with the one charging port connector for which connection of an external source of charging power is desired, and the light may have more than one opening located in respective predetermined locations relative to the respective charging connectors of the power source  200  or power sources  200  for making connections to different charging sources. 
     Examples of alternative keying features can include, e.g.: a rib on the wall of the cavity of the light and a complementary groove or slot in the power source, or a groove or slot in the wall of the cavity of the light and a complementary rib on the power source, or a nub on the wall of the cavity of the light and a complementary groove or slot in the power source, or a groove or slot in the wall of the cavity of the light and a complementary nub on the power source, and the like. 
     Electrical contacts  172 ,  374 ,  474  that make electrical connection to terminals  240  of power source  240  may be fixed contacts, movable contacts, spring-loaded contacts, and the like. 
     Electrical switches  140 ,  340 ,  440  may be any suitable electrical switch, e.g., a snap-dome switch, a transfer switch, leaf contacts, and the like, and may be with or without a mechanical latch to retain the contacts thereof in an open or closed position and/or with or without an electronic “latch” that responds to a momentary opening or closing of a contact as if it is a continuous opening or closing thereof as is the case for a mechanical latch. In certain embodiments, e.g., where more than one switch may be provided, one switch may have a mechanical latch operation to have priority over another switch that is a momentary switch. 
     The present arrangement is suitable for use with other types and kinds of portable lights. For example, where the portable light is for mounting to a weapon and may be used with a remote switch, a mechanically or electronically latched switch may be provided on the light itself so as to be a primary switch having priority over a secondary, e.g., remote, switch. 
     While certain features may be described as a raised feature, e.g., a ridge, boss, flange, projection, detent, or other raised feature, such feature may be positively formed or may be what remains after a recessed feature, e.g., a groove, slot, hole, indentation, recess, detent, or other recessed feature, is made. Similarly, while certain features may be described as a recessed feature, e.g., a groove, slot, hole, indentation, recess or other recessed feature, such feature may be positively formed or may be what remains after a raised feature, e.g., a ridge, boss, flange, projection or other raised feature, is made. In addition, where a raised feature engages a recessed feature, such as for a keying feature, e.g., a shaped projection that engages a complementary shaped receptacle, the relative positions of the raised and recessed features may be interchanged or other wise modified. 
     Each of the U.S. Provisional applications, U.S. patent applications, and/or U.S. patents, identified herein is hereby incorporated herein by reference in its entirety, for any purpose and for all purposes irrespective of how it may be referred to or described herein. 
     Finally, numerical values stated are typical or example values, are not limiting values, and do not preclude substantially larger and/or substantially smaller values. Values in any given embodiment may be substantially larger and/or may be substantially smaller than the example or typical values stated.