Abstract:
An apparatus for fueling a fuel-cell-powered device having a profile and a fuel inlet. The apparatus comprises at least one fuel port having an outlet and at least one adaptor associated with the fuel port. The adaptor is configured to receive the fuel-cell-powered device. Means for releasably and sealingly engaging the fuel inlet of the fuel-cell-powered device to the outlet of the fuel port are also provided. The outlet of the fuel port is operative to dispense fuel when it is in sealed engagement with the fuel inlet of the fuel-cell-powered device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit under 35 U.S.C. §119 of U.S. application No. 60/719,604 filed on 23 Sep. 2005 which is hereby incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     This invention relates to fuel-cell-powered portable devices, and in particular to methods and apparatus for fueling fuel-cell-powered portable devices. 
     BACKGROUND 
     A fuel cell is a device that converts a fuel into electricity through an electrochemical reaction. Fuel cells have applicability in a wide range of stationary and portable applications. Fuel cells vary in capacity and size. Some fuel cells are small and portable. Other fuel cell systems are very complicated plants that produce relatively large amounts of electrical power. 
     Fuel cells need fuel and an oxidant to operate. The fuel cell can run as long as fuel and an oxidant are supplied to the fuel cell. Fuel cells can be designed to operate using a wide range of fuels such as hydrogen, methanol, butane, formic acid, and borohydride compounds. Since fuels is consumed as a fuel cell operates to generate electrical power, a fuel-cell-powered device requires a refueling mechanism. Some fuel-cell-powered devices have refillable fuel cartridges. Other fuel-cell-powered devices have built-in on-board fuel storage reservoirs. 
     SUMMARY 
     There is a need for a refueling system capable of refueling fuel-cell-powered devices that use gaseous fuels such as hydrogen. A need also exists for refueling systems that can be readily adapted to refuel a variety of portable devices. A need also exists for refueling systems that can operate either connected to an external fuel source or from a source of fuel located on board the refueling system. A need also exists for refueling systems that are easy to use and do not require connections to an external power source to run. 
     Aspects of the invention provide refueling systems that address one or more of these needs. Refueling systems may be used for refueling a variety of fuel cell devices including, for example, fuel cell cartridges and portable fuel cell-powered devices that have on-board fuel reservoirs or external fuel cartridges. Fuel cell cartridges include, for example, satellite cartridges that may themselves be used to refuel portable devices and small portable fuel cartridges that may be integrated with or removably mounted in portable devices. 
     One aspect of the invention provides an apparatus for fueling a fuel cell device having a profile and a fuel inlet. The apparatus comprising at least one fuel port having an outlet and at least one adaptor adjacent to each fuel port. The adaptor has a recess shaped to receive the profile of the fuel cell device. Means for releasably and sealingly engaging the fuel inlet of the fuel cell device to the outlet of the fuel port are also provided. The outlet of the fuel port is operative to dispense fuel when it is in sealed fluid communication with the fuel inlet of the fuel cell device. 
     Another aspect of the invention provides a method of fueling a fuel cell device having a profile and a fuel inlet, the method comprising: providing a fuel source; providing an apparatus comprising at least one fuel port having an outlet and at least one adaptor having a recess shaped to receive the profile of the fuel cell device; releasably and sealingly engaging the outlet of the fuel port with the fuel inlet of the fuel cell device; allowing fuel to flow from the at least one fuel port to the fuel cell device; and removing the fuel cell device from the fuel port to stop the flow of fuel to the fuel cell device. 
     A further aspect of the invention provides refueling systems that can operate independently of any external fuel or electricity sources. Some such refueling systems can operate in both portable or stationary modes. Such refueling systems may have interchangeable refueling adaptors. This provides the flexibility to refuel a wide variety of devices of varying profiles, and the ability to interchange refueling adaptors without shutting down the system. 
     Yet another aspect of the invention provides refueling systems having an onboard compressed gas reservoir to facilitate both stationary and portable operation. Such a refueling system may have a modular system of fuel ports and refueling adaptors so that the system can be easily adapted to refuel a wide variety of devices. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In drawings which illustrate non-limiting embodiments of the invention: 
         FIGS. 1A and 1B  show front and rear isometric views of a refueling station according to an example embodiment of the invention; 
         FIGS. 2A and 2B  show front and rear isometric views of internal components of the refueling station of  FIGS. 1A and 1B ; 
         FIG. 3  shows a front isometric view of a refueling station according to another embodiment of the invention; 
         FIG. 4  shows a front isometric view of a refueling station according to another embodiment of the invention; 
         FIGS. 5A and 5B  show front and rear isometric views of a refueling station another embodiment of the invention; 
         FIGS. 6A and 6B  show front and rear isometric views of a refueling station according to another embodiment of the invention; 
         FIG. 7A  shows a refueling port for an example portable device; 
         FIG. 7B  shows the refueling port of  FIG. 7A  connected to an adaptor in a refueling station; and, 
         FIGS. 7C and 7D  illustrate the operation of an example fluid coupling for providing fluid communication between a portable device and a refueling station. 
     
    
    
     DESCRIPTION 
       FIGS. 1A and 1B  show a refueling system  10  for refueling fuel-cell-powered devices according to one embodiment of the invention. Refueling system  10  may be configured to deliver fuel to: fuel-cell-powered devices having on-board fuel reservoirs (which may be integrated or removable) and/or cartridges for storing fuel for use by fuel-cell-powered devices. Delivering fuel to a fuel reservoir while the reservoir is integrated with a fuel-cell-powered device and delivering fuel to a cartridge to be connected to a fuel-cell-powered device are both examples of fueling a fuel-cell-powered device. 
     Refueling system  10  may comprise: an enclosure  20 , a plurality of interchangeable refueling port adaptors  30   a ,  30   b ,  30   c  (collectively refueling port adaptors  30 ), a refueling pressure indicator  40 , and a fuel shutoff valve  50 . An optional external fuel supply port  60  and an external port shutoff valve  70  for isolating the external port  60  when not in use may be provided on refueling system  10 . 
     Enclosure  20  may be made of any suitable material, for example, a plastic, metallic, or composite material, or combinations thereof. External fuel supply port  60  may comprise, for example, a commercially-available threaded connector, a locking connector or another connector configured to connect to an available external source of fuel. 
       FIGS. 2A and 2B  show a refueling system  10  according to one specific embodiment of the invention. The illustrated refueling system  10  has a fuel storage cylinder  80  housed within enclosure  20 . Fuel storage cylinder is accessible through a removable panel  21  (see  FIG. 1B ). Fuel storage cylinder  80  is supported in enclosure  20 . For example, cylinder  80  may be mechanically constrained to a base plate  90  via a plurality of brackets  91   a ,  91   b  (collectively brackets  91 ) protruding from the base plate  90 . Brackets  91  may either be distinct components that are, for example, mechanically fastened, welded, brazed, or bonded to base plate  90 , or integral to the base plate  90  such as in the case of a molded plastic part, a cast metal part or combinations thereof. Fuel storage cylinder  80  may be replenished by (1) replacing fuel storage cylinder  80 , (2) removing and refilling fuel storage cylinder  80 , or (3) refilling storage cylinder  80  in-situ. 
     An internal port shutoff valve  100  for isolating onboard fuel storage cylinder  80  when not in use or not present is directly connected to the onboard fuel storage cylinder  80 . Downstream of internal port shutoff valve  100 , a fuel manifold  110  fluidically connects internal port shutoff valve  100  to a pressure regulator  120  that sets the refueling pressure. A flow rate regulator (not shown) may also be provided upstream or downstream of pressure regulator  120 . Downstream of pressure regulator  120 , fuel manifold  110  branches into at least one universal refueling ports  130   a ,  130   b , and  130   c  (collectively universal refueling ports  130 ). External fuel supply port  60  fluidically connects to fuel manifold  110  downstream of internal port shutoff valve  100  and upstream of pressure regulator  120 . 
     Pressure regulator  120  (and the flow rate regulator, if present) may be configured to either adjust the pressures and flow rates of fuel dispensed from each universal refueling port  130  together or independently. In the illustrated embodiment, independent adjustment permits refueling system  10  to simultaneous refuel up to three fuel cell devices each having different fuel pressure and/or flow rate requirements. 
     The number of universal refueling ports  130  provided by a refueling system  10  may be varied. An embodiment having only one universal refueling port is described below. Other embodiments may have four or more universal refueling ports to permit simultaneous refueling of four or more fuel-cell-powered devices and/or fuel cartridges for fuel-cell-powered devices. 
     Each universal refueling port  130  comprises an integral check valve  131 , which automatically seals the universal refueling port  130  when not in use, as illustrated in  FIG. 2A . Each universal refueling port  130  may be adapted to refuel any of a broad array of devices by installing an appropriate refueling port adaptor  30  to universal refueling port  130 . 
     Each refueling port adaptor  30  is configured to receive a specific type of device for refueling. In the illustrated embodiment, each adapter  30  defines a receptacle that has a cross-section shaped to accept devices having a given cross-sectional profile. The device profile specificity of refueling port adaptors  30  therefore safeguards against the wrong type of fuel cell device being inadvertently inserted into refueling system  10 . Refueling port adaptors  30  may be releasably held in place in refueling system  10  by, for example, a frictional-fit, magnetic, snap-fit/release, or latch mechanism and the like. Releasable fastening facilitates interchanging refueling port adaptors  30 . 
     Each refueling port adaptor  30  may comprise a mechanism for constraining the device being refueled. Constraint mechanisms include, for example, a threaded mechanism, a friction-fit mechanism, magnetic mechanism, snap-fit/release mechanism, latches and the like. 
       FIGS. 7A through 7D  show details of construction of a fuel port  602  of an example portable device  600  and a corresponding example refueling port adaptor  630  that receives portable device  600  in a receptacle  634 . Receptacle  634  is shaped to accept portable device  600 . As portable device  600  is inserted into receptacle  634 , fuel port  602  engages a fuel connector  636  of adaptor  630 . Fuel port  602  includes a seal  604  that seals to connector  636  before portable device  600  is fully inserted into receptacle  634 . 
     Refueling port adaptors  30  may also comprise an actuator member, such as a pin or the like that is moved by a device when the device is being inserted into the refueling port adaptor  30 . In the embodiment illustrated in  FIGS. 7A to 7D , actuator member  638  comprises a pin which is depressed by the introduction of a device  600  to be fueled. An actuator member (such as pin  638 ) may be operatively connected to a check valve such that when the actuator member is depressed, the check valve opens, allowing fuel to flow into the device being refueled. 
     In the embodiment illustrated in  FIGS. 7B to 7D , as portable device  600  is pushed the last part of the way into receptacle  634 , fuel port  602  displaces actuator pin  638  which, in turn, opens check valve  640  against the pressure exerted by spring  646  and any differential gas pressure across check valve  640 . When portable device  600  is removed from receptacle  634 , check valve  640  closes before the seal between fuel port  602  and connector  636  is broken. As shown in  FIG. 7C  when device  600  has been removed from refueling port adaptor  630 , actuator pin  638  is no longer depressed and check valve  640  has been returned to its closed position during removal of device  600 . Check valve  640  prevents further fuel discharge. 
     A pressure relief valve  140 , a purge valve  150 , and a refueling pressure indicator  40  may also be disposed along the fuel manifold  110  to which the universal refueling ports  130  are connected. Pressure relief valve  140  guards the system against pressure surges. Purge valve  150  can be used for expelling any trapped air that may be present in fuel manifold  110  when the system is first pressurized. Refueling pressure indicator  40  is visible from outside the refueling system enclosure  20  and provides the user with a visual indication of the system&#39;s current refueling pressure. Fuel shutoff valve  50 , which is accessible from outside the refueling system enclosure  20 , is also connected to fuel manifold  110  either upstream or downstream of pressure regulator  120 . 
     External fuel supply port  60  connects to fuel manifold  110  immediately downstream of the internal port shutoff valve  100 . External fuel supply port  60  is firmly supported. For example, it may be attached to base plate  90  or to at least one of brackets  91  extending from base plate  90 . Directly connected to, or integral with, external fuel supply port  60  is a check valve  160 , which is oriented to allow flow into the refueling system  10 , but to prevent any fuel discharge from the external fuel supply port  60 . Downstream of check valve  160  is external port shutoff valve  70 , which may be used to isolate the external fuel supply port  60 . 
     External port shutoff valve  70  then merges with fuel manifold  110  downstream of the internal port shutoff valve  100 . This arrangement of internal ( 100 ) and external ( 70 ) port shutoff valves facilitates two discrete refueling system  10  operating modes:
         Portable Operation: In portable operation mode, refueling system  10  can be used as a self-contained fuel source to refuel devices using fuel stored in its fuel storage cylinder  80 . This operating mode requires no external fuel source or grid electricity. This facilitates operation in remote areas while providing portability.   Stationary Operation: In stationary operation mode refueling system  10  may optionally be connected to an external fuel source such as a compressed gas cylinder or fuel supply line, such as typically available in industrial or laboratory environments, via external fuel supply port  60 . Such operation negates the need to periodically replace or refill fuel storage cylinder  80 . In some embodiments, onboard fuel storage cylinder  80  may be refilled from the external fuel source. In cases where a suitable external fuel source is available, cylinder  80  is not required for stationary operation and may be absent.       

       FIGS. 3 ,  4 ,  5 A,  5 B,  6 A and  6 B show refueling systems according to alternative embodiments of the invention.  FIG. 3  shows a refueling system  210 , having several identical refueling adaptors  230   a ,  230   b , and  230   c . A fuel cell device  200  is shown inserted into adaptor  230   b . Such a refueling system could be used to refuel a number of portable devices simultaneously. 
       FIG. 4  shows another refueling system  310  having three different refueling port adaptors  330   a ,  330   b  and  330   c  for connection to three different types of fuel cell devices. 
       FIGS. 5A and 5B  show a refueling system  410  having one refueling adaptor  430  adapted to fit a single type of device (not shown) such as a fuel-cell powered flashlight. Refueling system  410  has an external fuel supply port  460 , refueling pressure indicator  440 , and an on/off switch  450 . Release mechanism  470  indicates to the user when the device has been properly inserted into refueling adaptor  430 , for example, by making a clicking sound or changing its visual appearance (such as by visibly sliding, depressing, popping up, or otherwise moving). Release mechanism  470  may be depressed or otherwise operated to release the device from refueling adaptor  430 . 
     In addition to the illustrated components, refueling system  410  may comprise a pressure regulator for regulating hydrogen delivery pressure; a pressure relief valve for preventing system overpressure; a filter/flow control element for regulating hydrogen delivery flowrate; and a purge valve for preventing hydride poisoning by contaminant gases. 
     Externally, the illustrated refueling system  410  has minimal controls to avoid the potential for operator error. 
       FIGS. 6A and 6B  show a refueling system  510  having one refueling adaptor  530  adapted to fit a portable fuel cell cartridge (not shown). Similar to refueling system  410 , refueling system  510  also has an external fuel supply port  560 , refueling pressure indicator  540  and an on/off switch  550 . Release mechanism  570  indicates to the user when the portable fuel cell cartridge has been properly inserted into refueling adaptor  530 . Depressing release mechanism  570  releases the portable fuel cell cartridge from refueling adaptor  530 . 
     In some embodiments, adaptors for refueling specific types of portable device include pressure regulators, flow regulators, or means for controlling a pressure regulator or flow regulator of a refueling station to supply hydrogen or other fuel under conditions of flow, pressure or the like that are suitable for the portable devices to be refueled. 
     Refueling systems according to the embodiments described above can be adapted to refuel new types of portable devices by installing a new adaptor  30  that is compatible with the new type of portable device. Further, in the illustrated embodiments refueling is driven entirely by the pressure of fuel in the refilling system. Fuel gas flow commences when a device is inserted and ceases when the device is removed, without any user intervention or electrical controls. 
     While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that all such modifications, permutations, additions and sub-combinations be considered to be part of this invention.