CN1809941A - Fuel cell cartridge for portable electronic device - Google Patents

Abstract

The present invention provides a fuel cell assembly including a membrane electrode assembly, an anode plate, a cathode plate, a removable fuel cartridge, and a fuel delivery system. The assembly includes an anode, a cathode, and a polymer electrolyte membrane having a fuel side and an oxygen side. The fuel cartridge includes an expandable fuel bladder for receiving liquid fuel, an expandable pressure member in contact with the bladder for maintaining a positive pressure on the bladder, and a sealable exit port in fluid communication with the bladder. The fuel delivery system delivers fuel from the cartridge to the fuel side of the membrane. The removable fuel cartridge includes a rigid fuel container having a first container portion and a second container portion permanently enclosing the expandable fuel bladder and the expandable pressure member. The first container portion and the second container portion may be permanently affixed to one another with an adhesive.

Description

Fuel cell cartridge for portable electronic device

Cross Reference to Related Applications

A continuation-in-part application entitled "fuel cell assembly for a portable electronic device and port, controller, and regulation circuitry for an electronic device using a fuel cell as a power source", filed on 3.12.2002, is filed as application No.10/309,954, the entire contents of which are incorporated herein by reference.

The present application further claims priority from U.S. provisional patent application No.60/517,469 entitled "fuel cell assembly for portable electronic devices" filed on month 11 and 4 of 2003, U.S. provisional patent application No.60/431,139 entitled "improved fuel cell and fuel cell assembly for portable electronic devices" filed on month 12 and 4 of 2002, and U.S. provisional patent application No.60/430,591 entitled "improved rechargeable power supply apparatus and method for a laptop based fuel cell" filed on month 12 and 2 of 2002, the entire contents of which are incorporated herein by reference.

Technical Field

The present invention relates to a new and improved fuel cell assembly and cartridge for a portable electronic device. More particularly, the present invention is directed to a fuel cartridge for a liquid-fed direct methanol polymer electrolyte membrane fuel cell assembly.

Background

Polymer electrolyte membranes are useful in electrochemical devices such as batteries and fuel cells because they can act as electrolytes and separators. Such a membrane can be easily fabricated as a thin flexible membrane that can be used in batteries of different shapes.

Perfluorinated sulfonated hydrocarbon ionomers, such as NAFION from DuPont^®Or similar Dow perfluorinated polymers are currently used as polymer electrolytes for fuel cells. However, these prior art membranes have severe limitations for use in hydrogen/air fuel cells and liquid feed direct methanol fuel cells.

An example of a fuel cell including such a prior art membrane is shown in U.S. patent No.5,759,712 to Hockaday, which shows a surface replica fuel cell for a micro fuel cell power pack. The disclosed micro fuel cell power pack is configured for use as a power source for a cellular telephone. An evaporation manifold is provided for drawing fuel from the fuel storage cylinder.

It is particularly desirable for the fuel cell assembly to have a removable fuel cartridge that is capable of maintaining a positive pressure to facilitate the flow of fuel from the cartridge to the fuel cell assembly.

Disclosure of Invention

In one embodiment, the removable fuel cartridge includes a rigid fuel container having a first container portion and a second container portion, the container enclosing an expandable fuel bladder and an expandable pressure member. The first container portion and the second container portion may be permanently secured to each other. An adhesive may bond the container portions together. In a preferred embodiment, the liquid fuel is methanol.

The second chamber may include a metering valve in fluid communication with the first chamber through a first port, and wherein the second chamber includes a second port configured to be in fluid communication with an anode loop of the fuel cell assembly. The fuel metering valve can be controlled by an actuator located in the fuel cell assembly. The second chamber may include an inlet and an outlet for fluid communication with an anode loop of the fuel cell assembly, a fluid connector between the inlet and the outlet, and a metering valve in fluid communication with the first chamber and the fluid connector. The fuel metering valve can be controlled by an actuator located in the fuel cell assembly. The fuel cartridge may include a fuel filter positioned within the second chamber in fluid communication with the first chamber or the fluid connector. The fuel cartridge may include an ion exchange resin in fluid communication with the first chamber or the fluid connector. The second chamber may include an inlet and an outlet for fluid communication with an anode loop of the fuel cell assembly, a fluid connector between the inlet and the outlet, a metering valve in fluid communication with the first chamber, and a fuel feed port for fluid communication with the anode loop of the fuel cell assembly.

Another aspect of the invention is directed to a removable fuel cell cartridge for a liquid fuel cell assembly comprising a container having a first fuel chamber with at least one port for delivering fuel to the fuel cell assembly and an absorbent device having at least two ports, wherein at least one of the ports is in communication with the fuel cell assembly. The absorber device may be configured to remove water from the exhaust of the fuel cell assembly or carbon dioxide produced on the anode side of the fuel cell. The container may comprise a second chamber in which the absorption means is located. The first and second chambers may be separated by a stationary divider. The fuel cartridge may include one or more additional components selected from the group consisting of an air filter, a fuel filter, an ion exchange column, a fan, a pump control chip, a metering valve, a metering pump, a membrane, a water absorbent, a carbon dioxide absorbent, and a methanol absorbent.

It is an object of the present invention to provide a compact fuel cell cartridge for use in mobile telephones and other portable electronic devices.

It is another object of the present invention to provide a fuel cell cartridge for a portable electronic device that can be quickly refueled, thereby alleviating the problem of long time required to recharge the battery.

Yet another object of the present invention is to provide a fuel cell assembly that can be quickly and easily refueled using replaceable fuel cartridges that maintain a positive pressure of fuel.

It is a further object of the present invention to provide a removable fuel cartridge that is permanently sealed to inhibit inadvertent or intentional damage to the fuel bladder and/or the fuel contained therein.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Drawings

Fig. 1 is a perspective view schematically showing a fuel cell assembly according to the present invention in combination with a portable electronic device.

Fig. 2 is an exploded front perspective view of the fuel cell assembly shown in fig. 1 with the portable electronic device removed.

Figure 3 is an exploded rear perspective view of the fuel cell assembly shown in figure 2.

Figure 4 is a schematic view of a membrane electrode assembly of the fuel cell assembly of figure 1.

Figure 5 is an enlarged cross-sectional schematic view of the membrane electrode assembly shown in figure 4 without electrodes.

Figure 6 is a perspective view of the anode plate shown in figures 2 and 3.

FIG. 7 is a perspective view of the removable fuel cartridge of FIGS. 2 and 3, schematically illustrating the expandable fuel bladder and the expandable pressure member.

Fig. 8 is an exploded side perspective view of an alternative fuel cell assembly similar to that shown in fig. 1, with the portable electronic device removed.

Fig. 9(a) is an enlarged plan view of the cathode plate of the fuel cell assembly shown in fig. 8.

FIG. 9(b) is an enlarged cross-sectional view of the cathode plate shown in FIG. 9 taken along line 9-9 of FIG. 9 (a).

FIG. 10 is an exploded front perspective view of a removable fuel cartridge in the fuel cell assembly of FIG. 8.

FIG. 11 is an exploded front perspective view of a modified removable fuel cartridge for the fuel cell assembly of FIG. 8 similar to that shown in FIG. 10.

Figure 12(a) is an enlarged exploded perspective view of a two-way valve assembly for the fuel cell assembly of figure 8.

FIG. 12(b) is an enlarged perspective view of the two-way valve assembly shown in FIG. 12 (a).

FIG. 13 is an exploded front perspective view of an improved removable fuel cartridge in accordance with the present invention similar to that shown in FIG. 10.

FIG. 14 is an exploded front perspective view of another modified removable fuel cartridge in accordance with the present invention similar to that shown in FIG. 10.

FIG. 15 is an exploded front perspective view of another modified removable fuel cartridge in accordance with the present invention similar to that shown in FIG. 10.

FIG. 16 is an exploded front perspective view of another modified removable fuel cartridge in accordance with the present invention similar to that shown in FIG. 10.

FIG. 17 is an exploded front perspective view of another modified removable fuel cartridge in accordance with the present invention similar to that shown in FIG. 10.

FIG. 18 is an exploded front perspective view of another modified removable fuel cartridge in accordance with the present invention similar to that shown in FIG. 10.

Figure 19 is a schematic view of a water recovery system that may be used in conjunction with a fuel cell assembly according to the present invention, such as the fuel cell assemblies shown in figures 1 and 8.

Figure 20 is a schematic flow diagram of a fuel cell assembly that may be used in conjunction with a fuel cell assembly according to the present invention, such as the fuel cell assemblies shown in figures 1 and 8.

FIG. 21 is a schematic view of a removable fuel cartridge with an additional bladder in accordance with the present invention.

Fig. 22 is a schematic diagram of a fuel cell assembly adapted to accommodate freezing of water (freezability) in accordance with the present invention.

Figure 23 is a schematic diagram of a fuel cell assembly suitable for utilizing product carbon dioxide in accordance with the present invention.

FIG. 24 is a schematic view of a portion of a fuel cell assembly having a replaceable fuel cartridge in accordance with the present invention.

FIG. 25 is a schematic view of a portion of a fuel cell assembly having an improved replaceable fuel cartridge in accordance with the present invention.

FIG. 26, FIG. 26(a), FIG. 26(b) and FIG. 26(c) are schematic illustrations of a refillable injector assembly, a replaceable injector assembly, an internal injector assembly and a replaceable cartridge injector assembly, respectively, according to the present invention.

FIG. 27 is a schematic view of a refillable injector assembly according to the present invention.

FIG. 28 is a schematic view of another refillable injector assembly according to the present invention.

FIG. 29 is a schematic view of a disposable syringe assembly according to the present invention.

FIG. 30 is a schematic view of another refillable injector assembly according to the present invention.

FIG. 31 is a schematic view of another refillable injector assembly according to the present invention.

FIG. 32 is a schematic view of another refillable injector assembly according to the present invention.

FIG. 33 is a schematic view of another replaceable syringe assembly according to the present invention.

Fig. 34 is a schematic view of an internal injector assembly according to the present invention.

Fig. 35(a) and 35(b) are schematic views of alternative fuel reservoir configurations using bellows according to the present invention, shown as empty and full, respectively.

Fig. 36(a), 36(b), and 36(c) are schematic views of other fuel reservoir configurations utilizing spring-biased compression plates in accordance with the present invention.

FIG. 37 is a schematic view of an alternative configuration using multiple fuel reservoirs in accordance with the present invention.

FIG. 38 is a schematic view of an alternative replaceable fuel cartridge in accordance with the present invention.

Detailed Description

The present invention will now be described in detail with reference to the preferred embodiments thereof and with reference to the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the scope and spirit of the invention as defined by the appended claims.

The acidic polymer includes acidic subunits, which preferably include acidic groups including sulfonic acid groups, phosphoric acid groups, and carboxylic acid groups. Examples of polymers comprising sulfonic acid groups include perfluorinated sulfonated hydrocarbons such as NAFION^®(ii) a Sulfonated aromatic polymers such as sulfonated polyether ether ketone (sPEEK), sulfonated polyether ether sulfone (sPEES), sulfonated polybenzobindole, sulfonated polybenzothiazole, sulfonated polybenzimidazole, sulfonated polyamide, sulfonated polyether imide, sulfonated polyphenylene oxide, sulfonated polyphenylene sulfide, and other sulfonated aromatic polymers. The sulfonated aromatic polymers may be partially or fully fluorinated. Other sulfonated polymers include polyvinylsulfonic acid, sulfonated polystyrene, copolymers of acrylonitrile and 2-acrylamido-2-methyl-1 propane sulfonic acid, copolymers of acrylonitrile and vinylsulfonic acid, copolymers of acrylonitrile and styrenesulfonic acid, copolymers of acrylonitrile and methacryloyloxyethyleneoxypropane sulfonic acid, copolymers of acrylonitrile and methacryloyloxyethyleneoxytetrafluoroethylenesulfonic acid, and the like. These polymers may be partially or fully fluorinated. Any class of sulfonated polymers includes sulfonated polyphosphazenes, such as poly (sulfophenoxy) phosphazenes or poly (sulfoethoxy) phosphazenes. The phosphazene polymer may be partially or fully sulfonated. Sulfonated phenylsiloxanes and copolymers, poly (sulfoalkoxy) phosphazenes, poly (sulfotetrafluoroethoxypropoxy) siloxanes. In addition, copolymers of any polymer may be used. Preferably the sPEEK is sulfonated between 60% and 200%, more preferably between 70% and 150%, most preferably between 80% and 120%. In this regard, 100% sulfonation indicates one sulfonic acid group per polymer repeat unit.

Examples of polymers having carboxylic acid groups include polyacrylic acid, polymethacrylic acid, polymers thereof each including copolymers with vinylimidazole or acrylonitrile, and the like. The polymer may be partially or fully fluorinated.

Examples of acidic polymers that include phosphate groups include polyvinyl phosphate, polybenzimidazole phosphate, and the like. The polymer may be partially or fully fluorinated.

The basic polymer comprises basic subunits, which preferably comprise basic groups such as aromatic amines, aliphatic amines, or heterocyclic nitrogen-containing functional groups. Examples of basic polymers include aromatic polymers such as polybenzimidazole, polyvinylimidazole, N-alkyl or N-aryl polybenzimidazoles, polybenzthiazoles, polybenzoxazoles, polyquinolines, and polymers containing functional groups with heteroaromatic nitrogens such as oxazoles, isoxazoles, carbazoles, indoles, isoindoles, 1,2, 3-oxadiazoles, 1,2, 3-thiadiazoles, 1,2, 4-thiadiazoles, 1,2, 3-triazoles, benzotriazoles, 1,2, 4-triazoles, tetrazoles, pyrroles, N-alkyl or N-arylpyrroles, pyrrolidines, N-alkyl and N-arylpyrrolidines, pyridines, pyrazolyl and the like. These polymers may be partially or fully fluorinated. Examples of aliphatic polyamines include polyethyleneimine, polyvinylpyridine, poly (allylamine), and the like. These basic polymers may be partially or fully fluorinated. Polybenzimidazole (PBI) is a preferred basic polymer. Polyvinylimidazole (PVI) is a particularly preferred basic polymer.

The elastomeric polymer includes elastomeric subunits which preferably include elastomeric groups such as nitrile, vinylidene fluoride, siloxane and phosphazene groups. Examples of elastomeric polymers include polyacrylonitrile, acrylonitrile copolymers, polyvinylidene fluoride, vinylidene fluoride copolymers, polysiloxanes, siloxane copolymers, and polyphosphazenes, such as poly (trifluoromethylethoxy) phosphazene.

Elastomeric polymers may be added to the polymer film in the form of polymerizable monomers to produce a semi-interpenetrating network. The monomer may be polymerized photochemically or by thermal treatment to obtain a semi-IPN.

Elastomeric copolymers may refer to elastomeric polymers that include elastomeric subunits and one or more acidic or basic subunits. For example, if an acidic polymer such as sPEEK is used, an elastomeric copolymer comprising elastomeric subunits and basic subunits may be used in the binary component. Alternatively, if a basic polymer is used, the elastomeric copolymer will include elastomeric subunits and acidic subunits. Such binary mixtures may be used with other polymers and copolymers to form additional components.

It will be appreciated that other polymers and copolymers may also be used, such as those described in U.S. patent application No.10/438,186 entitled "Sulfonated copolymers" filed on 5/13/2003 and U.S. patent No.10/3438,299 entitled "Ion Conductive Block copolymers" filed on 5/13/2003, which are incorporated herein by reference.

As used herein, a Membrane Electrode Assembly (MEA) refers to a Polymer Electrolyte Membrane (PEM) in combination with anode and cathode catalysts located on opposite sides of the PEM. It may also include anode and cathode electrodes in electrical contact with the catalyst layer.

Fig. 1 shows a fuel cell assembly 31 for a portable electronic device 32 according to the present invention. In the illustrated embodiment, the fuel cell assembly is a liquid fuel cell assembly and the portable electronic device is a mobile phone. Methanol is a convenient source of liquid fuel that is easy to handle and easy to contain in a simple plastic enclosure. Methanol is also relatively inexpensive and is currently widely available. It will be appreciated that other types of fuels may also be used.

The fuel cell assembly 31 as shown is suitable for use in a mobile telephone such as a cellular telephone. For example, the fuel cell assembly 31 may be configured to provide a continuous power source to a mobile phone that typically has a power consumption ranging from 360mA at 3.3V (1.2W) when closest to the corresponding transmitter to 600mA at 3.3V (1.98W) when furthest from the corresponding transmitter. It should be understood that the fuel cell assembly of the present invention may be configured to provide sustained power to other portable electronic devices having various ranges of power consumption while remaining within the scope of the present invention. For example, fuel cell assemblies according to the present invention may be used to provide power to Personal Digital Assistants (PDAs), notebook and laptop computers, portable CD players, and other portable electronic devices.

As shown in fig. 2 and 3, fuel cell assembly 31 generally includes membrane electrode assembly 33, anode plate 37, cathode plate 38, removable fuel cartridge 39, fuel delivery system 40, and voltage regulator 41. Fuel cell assembly 31 is assembled using various fasteners and/or snap features and/or pressure sensitive adhesives. For example, threaded fasteners 42 extend through cathode plate 38, through mounting holes 43, 44, and 45 in cathode electrode 48, membrane electrode assembly 33, and anode electrode 49, respectively, and into mounting holes 50 in anode plate 37 and engage nuts 51, as viewed from left to right in FIG. 2. The pressure sensitive adhesive applied to the abutting surfaces of the components may be in addition to or in place of the threaded fastener 42. It should be appreciated, however, that other assembly methods may also be used.

The electrodes are in direct or indirect electrical contact with the polymer electrolyte membrane 53 and can form an electrical circuit that includes the polymer electrolyte membrane 53 and a load of the portable electronic device 32 to which the electrical current is supplied. More specifically, the first catalyst 54 is connected to the anode side of the polymer electrolyte membrane 53 in an electrocatalytic manner so as to facilitate oxidation of an inorganic fuel such as methanol, as schematically shown in fig. 4. This oxidation generally produces protons, electrons, and carbon dioxide, as well as water. Since polymer electrolyte membrane 53 is substantially impermeable to organic fuels such as methanol and carbon dioxide, these components remain on the anode side of polymer electrolyte membrane 53. Electrons generated by the electrocatalytic reaction are transported from the cathode electrode 48 to the load and then to the anode electrode 49. Balancing this direct current electron flow is the migration of protons or other suitable cationic species, i.e. an equal amount of protons through the polymer electrolyte membrane to the anode compartment. In the presence of the transferred protons, the oxygen undergoes electrocatalytic reduction to water.

The membrane electrode assembly 33 is generally used to separate the fuel cell assembly 31 into anode and cathode compartments. In such fuel cell systems, an organic fuel such as methanol is fed to the anode compartment and an oxidant such as oxygen or ambient air is fed to the cathode compartment. Depending on the specific use of the fuel cell assembly, multiple fuel cells may be combined to achieve a suitable voltage and power output. Such applications include use as a power source for portable electronic devices such as cellular telephones and other communication devices, video and audio consumer electronics, laptop computers, notebook computers, personal digital assistants and other computing devices, geographic positioning systems (GPS's), and the like.

The membrane electrode assembly 33 comprises a plurality of membrane electrode assembly cells, each cell typically comprising an anode 49, a cathode 50 and a polyelectrolyte membrane 53. Each polymer electrolyte membrane is a continuous plate with catalytic layers. The polymer electrolyte membrane forms an electrolyte between the catalytic layers and is sandwiched between the anode and the cathode together with the catalytic layers. The polymer electrolyte membrane 53 has a fuel side and an oxygen side located adjacent the anode 49 and cathode 48, respectively, as schematically shown in fig. 4. The membrane electrode assembly 33 further includes a first catalyst 54 and a second catalyst 59 on the fuel side and the oxygen side of the polymer electrolyte membrane 53, respectively. The catalyst on the anode side of the polymer electrolyte membrane is preferably a platinum ruthenium catalyst, and the catalyst on the cathode side is preferably a platinum catalyst.

The anode 49 is electrically connected to the first catalyst 54 and the cathode 48 is electrically connected to the second catalyst 59. In one embodiment, the electrodes are constructed of gold plated stainless steel. The electrodes of each membrane electrode assembly unit are sized and configured to provide electrical contact between the electrodes and the respective catalytic layers of the membrane electrode assembly unit. Preferably, each electrode comprises a copper joint.

Fig. 5 is a cross-sectional view of the membrane electrode assembly 33 without electrodes. The membrane electrode assembly includes a polymer electrolyte membrane, first and second catalyst layers and generally at least one gas and water permeable layer on the cathode side for transporting air to the cathode catalyst layer and water away from the cathode catalyst layer. Usually carbon paper or carbon cloth is used for this purpose. Further, a carbon lining is preferably provided on the anode catalyst layer to prevent the catalyst layer from being damaged by the electrode. Since the liner typically comprises an electrically conductive material such as carbon, electrodes may be placed directly on the liner to complete the membrane electrode assembly.

Various films may be used according to the present invention. For example perfluorinated hydrocarbon sulfonated ionomers, such as NAFION, may be used to form polymer electrolyte membranes in accordance with the present invention. It should be appreciated that other membranes may also be used.

In one embodiment, the polymer electrolyte membrane includes a first, a second, and optionally a third polymer, wherein the first polymer is an acidic polymer including acidic subunits, the second polymer is a basic polymer including basic subunits, and wherein (i) the optional third polymer is an elastomeric polymer including elastomeric subunits, or (ii) at least one of the first or second polymers is an elastomeric copolymer further including one elastomeric subunit. Such polymer electrolyte membranes and polymer compositions are thus filed on 6.1.2001 as membrane electrode assemblies, fuel cells and electrochemical devices using such membranes in co-pending U.S. patent application No.09/872,770 entitled "polymer composition"; and the corresponding international application, international publication No. wo01/94450a2, published as 13/12/2001, entitled "Polymer Composition"; U.S. patent application No.10/438,299 entitled "Ion Conductive Block copolymers" filed on 5/13/2003; U.S. provisional patent application No60/449,299 entitled "Ionic Conductive Polymers" filed on 20/2/2003; U.S. patent application No.10/438,186 entitled "Sulfonated Copolymer" filed on 13/5/2003; U.S. patent application No.10/351,257 entitled Acid-based proton conducting Polymer Blend Membrane, filed on 23/1/2003, the entire contents of which are incorporated herein by reference.

Referring to fig. 2, anode plate 37 includes an internal recess that forms a fuel chamber 60 that is fluidly connected to the fuel side of polymer electrolyte membrane 53. Anode plate 37 includes a plurality of posts 61 extending through fuel chamber 60 toward anode 49 for biasing anode 49 into electrical contact with polymer electrolyte 53. Anode plate 37 includes a plurality of exhaust ports 64, as shown in FIG. 6. An exhaust port extends through sidewall 65 thereby providing an exhaust port through which carbon dioxide generated within fuel chamber 60 may flow.

Cathode plate 38 forms an enclosure or sleeve 66 having a recess 70 that receives membrane electrode assembly 33, anode plate 37 and removable fuel cartridge 39. The enclosure 66 also includes engagement structure to selectively engage a mobile phone or other portable electronic device. The illustrated enclosure includes an engagement track 71 extending along each side wall 72 of the enclosure for slidably engaging the portable electronic device 32. The enclosure 66 also includes engagement tabs 75 for selectively latching the fuel cell assembly 31 to the portable electronic device 32. Contacts are also provided to transfer electrical power to the mobile phone.

The capsule may be injection molded, however it is understood that other methods of forming the capsule may also be used. Such as the capsule may be machined or the like.

In the embodiment shown in fig. 1, the enclosure 66 includes a plurality of air channels 76 designed into an outer surface 77 of the enclosure 66, the outer surface 77 of the enclosure 66 generally being in contact with the hand of the user of the mobile phone. Gas inlets 82 are located in one or more of the grooves 76 to provide oxygen to the cathode chamber. In particular, oxygen inlet 82 extends from the bottom of one or more grooves 76 to the oxygen side of polymer electrolyte membrane 53. Such a configuration minimizes the resistance to airflow through the exhaust and intake ports by the palm of the user's hand.

Removable fuel cartridge 39 generally includes an expandable fuel bladder 86, an expandable pressure member 87 and a sealable exit port 88, as schematically illustrated in FIG. 7. Removable fuel cartridge 39 includes a rigid container 92 enclosing expandable fuel bladder 86 and expandable pressure member 87. In one embodiment, rigid container 92 is formed in two portions 95, 96 that are permanently secured to one another so that the fuel cartridge cannot be easily disassembled. It should be understood that the rigid container may be formed from one, two, three or more separate components, so long as the components form a rigid housing for supporting and enclosing the fuel bladder. Thus, for the purposes of the present invention, the term "portion" refers to the structural member that forms the rigid container of the removable fuel cartridge. While portions 95 and 96 are substantially symmetrical, it will be appreciated that the container components may also be asymmetrical. For example, one rigid container portion may be a bottomless cylinder that is sealed by another rigid portion having a corresponding bottom shape.

The container portions 95, 96 may be formed from injection moulded plastics material in a known manner. It should be understood that other suitable materials and other suitable manufacturing methods may be used in accordance with the present invention. For example, the container portion may be formed from plastic, metal, composite materials, and/or other suitable materials. The container portion may be produced by casting, machining, molding, stamping, and/or other suitable manufacturing means.

In the embodiment shown, the container portions 95, 96 are permanently secured to one another using an adhesive. It should be understood that other suitable means may also be used in accordance with the present invention, including, but not limited to, sonic welding, thermal welding, solvent bonding, and/or permanent adhesives. The permanently secured together construction of container portions 95, 96 promotes the overall safety of fuel cartridge 39, as well as the safety of fuel cell assembly 31 and portable electronic device 33, since it prevents inadvertent or intentional tampering with or misuse of fuel bladder 86 and/or the fuel contained therein.

The fuel cartridge is sized and configured such that the fuel bladder is capable of holding at least about 5 cubic centimeters of methanol, preferably at least about 7 cubic centimeters of methanol, and most preferably at least 10 cubic centimeters of methanol. In the illustrated embodiment, a pair of spring clips 93 are provided to engage the container 92 and the enclosure 66 together and hold the container in place until the user removes the container 92 from the enclosure to refuel the fuel cell assembly 31.

Expandable fuel bladder 86 receives liquid fuel for supply to membrane electrode assembly 33. Expandable fuel bladder 86 is formed from a substantially methanol-impermeable sheet of plastic material and/or other polymeric material. Examples of suitable sheets of plastic material include nylon, urethane and polyethylene, silicone rubber, however, it will be appreciated that other materials may also be used.

Expandable pressure member 87 is in contact with fuel bladder 86 in such a manner that a positive pressure is maintained on and within the bladder, thereby pressurizing the bladder. Sealable exit port 88 is in fluid communication with fuel bladder 86. In the illustrated embodiment, the expandable pressure member 87 is a compressed foam member, preferably constructed of an open cell foam material. The compressed foam member is resilient and applies a spring member bias to fuel bladder 86 thereby maintaining a positive pressure on the bladder. Other pressure members may also be used in accordance with the present invention. For example, a spring-biased member may apply a force to fuel bladder 86 to maintain a positive pressure on the bladder.

In the illustrated embodiment, sealable exit port 88 of replaceable fuel cartridge 39 includes a septum 94, as shown in FIG. 7. Septum 94 comprises a substantially self-sealing membrane. Referring to FIG. 3, fuel delivery system 40 includes a needle 97 extending into outlet 88 and through septum 94 for fluidly connecting fuel bladder 86 to the fuel side of polymer electrolyte membrane 53. Sealable outlet 88 is sized and configured to mate with needle 97. In one embodiment, the sealable exit port comprises one INTERLINK^®A fluid coupling adapter manufactured by Baxter International inc. In particular, fuel delivery system 40 includes a needle 97 insertable into septum 94. It should be understood that other types of fluid connectors may also be used in accordance with the present invention.

Enclosure 66 is also provided with a release latch 98 for disengaging removable fuel cartridge 39 from fuel delivery system 40. Release latch 98 is slidably disposed on one side of enclosure 66 and engages septum 94 of removable fuel cartridge 39. As shown in FIG. 2, sliding release latch 98 downward pushes against outlet port 88, thereby pushing removable fuel cartridge 39 at least partially outward past bottom wall 103 of enclosure 66, thereby at least partially disengaging removable fuel cartridge 39 from fuel delivery system 40.

Fuel delivery system 40 fluidly connects fuel bladder 86 of replaceable fuel cartridge 39 to fuel chamber 60 of anode plate 37. Fuel delivery system 40 includes needle 97, needle block 105, one-way duckbill valve 108, manifold block 109, and manifold 110 connected in series interconnecting fuel bladder 86 and fuel chamber 60. Needle block 105 supports needle 97 and positions needle 97 for needle penetration through removable outlet 88 of fuel cartridge 39 when the fuel cartridge is inserted into fuel cell assembly 31. Needle block 105 fluidly interconnects needle 97 and one-way duckbill valve 108. Needle block 105 preferably includes a barb for engaging an end of duckbill valve 108.

One-way duckbill valve 108 is provided to prevent fuel from flowing through fluid transfer system 40 away from fuel chamber 60 and the fuel side of polymer electrolyte membrane 53. One-way duckbill valve 108 is engageable with a protrusion 115 on container 92 of the removable fuel cartridge such that when fuel cartridge 39 is removed from fuel cell assembly 31, valve 108 is closed and when the fuel cartridge is inserted into the fuel cell assembly, valve 108 is open. It should be understood that other one-way valves may also be used in accordance with the present invention, including, but not limited to, Schrader-type valves, needle valves, and ball valves. When fuel cartridge 39 is inserted into fuel cell assembly 31, one-way valve 108 remains open, allowing fuel to flow from the cartridge to fuel chamber 60, whereby mass transfer occurs within the fuel chamber. Fuel flow from fuel cartridge 39 to fuel chamber 60 is facilitated by maintaining a positive pressure on fuel bladder 86.

Manifold block 109 fluidly interconnects one-way duckbill valve 108 and manifold 110. The preferred manifold block 109 includes a barb for engaging the other end of the one-way duckbill valve 108. Manifold 110 is in fluid communication with a plurality of fuel inlets 119 located in and extending through a bottom wall 120 of anode plate 37, as shown in fig. 6. Although fuel inlet 119 is shown extending through bottom wall 120 of anode plate 37, it should be understood that the fuel inlet may be disposed elsewhere on the anode plate.

The voltage and current regulator 41 shown in fig. 1 and 2 includes circuitry and a battery for monitoring and/or regulating the voltage and/or power supplied to the portable electronic device 33. Regulator 41 is described in co-pending U.S. provisional application No.60/295,475, filed on 1/6/2001 and entitled INTERFACE, CONTROL, ANDREGULATOR CIRCUIT FOR FUEL CELL powered DEVICES.

In operation and use, a user will insert removable fuel cartridge 39 into fuel cell assembly 31 such that needles 87 penetrate spacers 94, thereby allowing fuel to flow from fuel bladder 86 to polymer electrolyte membrane 53 of membrane electrode assembly 33. Once fuel cartridge 39 is substantially depleted of fuel, the user slides release latch 98 downward to disengage the fuel cartridge from fuel cell assembly 31. The user then replaces the spent fuel cartridge with a new, i.e., fuel-filled, cartridge and inserts the new cartridge in the same manner as described above.

In another embodiment of the invention shown in fig. 8, a fuel cell assembly 31a is similar to the fuel cell assembly 31 described above, but includes several modifications as described below. Like reference numerals are used in fuel cell assembly 31a and fuel cell assembly 31 to denote like parts.

As shown in FIG. 8, fuel cell assembly 31a generally includes membrane electrode assembly 33a, anode plate 37a, cathode plate 38a, removable fuel cartridge 39a, fuel delivery system 40a and voltage regulator 41 a. Fuel cell assembly 31a is assembled in the same manner as discussed above in connection with the embodiment of fig. 2 using threaded fasteners 42a that extend through cathode plate 38a, cathode electrode 48a, membrane electrode assembly 33a, anode electrode 49a, and anode plate 37a and mate with nuts 51 a.

The electrodes are in direct or indirect electrical contact with the polymer electrolyte membrane 53a and can constitute an electrical circuit that includes the polymer electrolyte membrane 53a and a load of the portable electronic device to which an electric current is supplied in the same manner as described above. The membrane electrode assembly 33a is typically used to divide the fuel cell assembly 31a into an anode chamber and a cathode chamber.

In this embodiment, cathode plate 38a is constructed of anodized aluminum. However, it should be understood that other materials may be used in accordance with the present invention. For example, the cathode plate may be constructed of polycarbonate or other suitable material. Since aluminum is an electrical conductor, cathode plate 38a is anodized to provide an electrical insulation layer. It will be appreciated that other forms of insulation may be used instead of or in addition to the anodising cathode plate.

Preferably, an insulating layer 122 is also provided between cathode plate 38a and cathode electrode 48a to further prevent the aluminum cathode plate from shorting the individual cells within the fuel cell assembly and significantly degrading performance. For example, if the anodization of the cathode plate is scratched, the insulating layer will prevent the cathode plate from shorting one or more battery cells. In the illustrated embodiment, the insulating layer 122 is composed of vinyl, however, it should be understood that other electrically insulating materials may be used in accordance with the present invention.

Referring to fig. 8, anode plate 37a includes an internal recess that constitutes a fuel chamber in fluid connection with the fuel side of polymer electrolyte membrane 53 a. Anode plate 37a includes a plurality of posts 61a extending through the fuel chamber toward anode 49a for biasing anode 49 into electrical contact with polymer electrolyte membrane 53a in the same manner as anode plate 37 described above.

Cathode plate 38a, along with enclosure or housing 66a, defines a recess that receives membrane electrode assembly 33a, anode plate 37a, and removable fuel cartridge 39 a. The enclosure 66a also includes engagement structure for selectively engaging a mobile phone or other portable electronic device. Preferably, the enclosure is constructed of anodized aluminum or other suitable material similar to the cathode plate. The enclosure shown includes engagement rails 71a extending along each side wall of the enclosure 66a for slidably engaging the portable electronic device.

As shown in FIG. 9(b), cathode plate 38a has a convex shape with a plurality of laterally extending air channels 76a disposed within outer convex surface 77a of cathode plate 38 a. If the fuel cell assembly 31a is used in conjunction with a mobile phone, the outer surface 77a will typically be in contact with the hand of the user of the mobile phone during use. The air channels 76a are formed between a plurality of wide or tall laterally extending webs 124. An inlet 82a is located in one or more of the grooves 76a for supplying oxygen to the cathode chamber. The tall webs 124 intersect with a plurality of narrow or short longitudinally extending webs 125, thereby forming the oxygen inlet 82 a. The inlet 82a extends to the oxygen side of the polymer electrolyte membrane 53 a. Such a configuration minimizes the impedance of the gas passing through the exhaust and inlet ports by the palm of the user's hand.

The bent configuration of cathode plate 38a further allows for side venting when cathode plate 38a and any portable electronic device, such as a mobile phone, attached thereto, even when the assembly is placed on a flat surface, such as a table or chair. In the embodiment shown in FIG. 9(b), cathode plate 38a has a convex profile, however, it should be understood that a convex profile or other curved profile may also be used in accordance with the present invention.

As shown in FIG. 10, removable fuel cartridge 39a generally includes an expandable fuel bladder 86a, a pair of expandable pressure members 87a and a sealable exit port 88 a. Removable fuel cartridge 39a includes a rigid container 92a constructed of anodized aluminum or other suitable material including, but not limited to, ABS (acrylonitrile butadiene styrene), polycarbonate, polyurethane, or stamped sheet metal. Container 92a encloses expandable fuel bladder 86a and expandable pressure members 87 a.

Expandable fuel bladder 86a receives and stores liquid fuel for supply to membrane electrode assembly 33 a. Expandable fuel bladder 86a is a plastic material that is substantially impermeable to methanol and conforms to the interior shape of container 92a by vacuum forming. The vacuum-formed configuration of fuel bladder 86a significantly increases the amount of fluid stored within container 92 a. Sealable exit port 88a is in fluid communication with fuel bladder 86 a.

Expandable pressure member 87a contacts fuel bladder 86a such that a positive pressure is maintained on and within the fuel bladder. In the illustrated embodiment, each expandable pressure member 87a is a compliant foam member with good volumetric efficiency, including, but not limited to, the type used in sound barriers and sold by E-A-R Specialty Composites of Indianapolis, Indiana. The compressed foam member is resilient and acts as a spring member that biases the fuel bladder 86a thereby maintaining a positive pressure on the bladder. Preferably the pressure member is cut from sheet material into the internal shape of cartridge 39 a. It should be understood that other pressure members and devices may be used in accordance with the present invention to provide positive pressure within the fuel bladder.

In the embodiment shown in FIG. 8, replaceable fuel cartridge 39a includes cartridge port or outlet 88a which mates with device port 127, thereby forming a two-way shut-off valve 128, as shown in FIGS. 12(a) and 12 (b). The bi-directional valve 128 is a spring-loaded device in which the outlet port 88a includes a spring 129 that biases a valve member 130 toward a sealed position so that the cartridge 39a is fluidly sealed when the cartridge is removed from the fuel cell assembly 31a and is open when the cartridge is inserted into the fuel cell assembly. Similarly, device port 127 of valve 128 includes a spring 134 that biases a valve member 135 toward a sealing position so that fuel delivery system 40a of fuel cell assembly 31a is sealed when cartridge 39a is removed from fuel cell assembly 31a and opened after insertion of the cartridge into the fuel cell assembly. It should be understood that port 88a is equally applicable to the replaceable fuel cartridges described above and below, as well as other fuel cartridge configurations in accordance with the present invention. It should also be understood that other types of fluid connectors may also be used in accordance with the present invention.

When cartridge 39a is inserted into fuel cell assembly 31a and outlet port 88a is engaged with device port 127, fuel bladder 86a is fluidly connected to the fuel chamber of anode plate 37a via fuel delivery system 40a in a manner similar to that described above with respect to fuel delivery system 40. The positive pressure maintained on fuel bladder 86a facilitates the flow of fuel from fuel cartridge 39a to fuel chamber anode plate 37 a. In operation and use, the fuel cell assembly 31a is used in the same manner as the fuel cell assembly 31 described above.

In another embodiment of the present invention, as shown in FIG. 11, a spring-loaded replaceable cartridge 39b includes an alternative structure for maintaining a positive pressure in fuel bladder 86 b. In particular, cartridge 39b includes a pair of compression plates 138, 139 that are biased against each other and against fuel bladder 86b by a pair of leaf springs 140, 141. It will be appreciated that other mechanical pressure members may be used to provide positive pressure on and within the fuel bladder according to the present invention.

In another embodiment of the present invention, as shown in FIG. 13, a removable fuel cartridge 39c is similar to removable fuel cartridge 39a described above, but includes a number of modifications as described below. Like components of removable fuel cartridge 39c and removable fuel cartridges 39, 39a, 39b described above are depicted with like reference numerals.

As shown in FIG. 13, removable fuel cartridge 39c generally includes an expandable fuel bladder 86c, a pair of expandable pressure members 87c and a sealable exit port 88 c. Removable fuel cartridge 39c includes a rigid container 92c constructed of polycarbonate or other suitable material. Container 92c includes two container portions 95c and 96c that are permanently bonded or otherwise assembled together such that the container permanently houses expandable fuel bladder 86c and expandable pressure member 87 c. The permanently affixed configuration of container portions 95c and 96c promotes the overall safety of fuel cartridge 39c, as well as the safety of the fuel cell assembly and the portable electronic device in which it is used, since such a configuration prevents inadvertent or intentional damage and/or misuse of the fuel bladder and the fuel contained therein.

In another embodiment of the present invention shown in FIG. 14, removable fuel cartridge 39d is similar to removable fuel cartridges 39a and 39c described above, but includes several modifications as described below. Like reference numerals have been used to identify like components in removable fuel cartridge 39d and removable fuel cartridges 39, 39a, 39b, and 39c described above.

As shown in FIG. 14, removable fuel cartridge 39d generally includes an expandable fuel bladder 86d, a pair of expandable pressure members 87d and a sealable exit port 88 d. Removable fuel cartridge 39d includes a rigid container 92d formed of anodized aluminum, or other suitable material including, but not limited to, polycarbonate or stamped sheet metal. Container 92d includes two container portions 95d and 96d that are permanently secured together by rivets 144 or other suitable permanent fasteners such that the container permanently houses expandable fuel bladder 86d and expandable pressure members 87 d. The permanently affixed configuration of container portions 95d and 96d promotes the overall safety of fuel cartridge 39d, as well as the safety of the fuel cell assembly and the portable electronic device in which it is used, since this configuration prevents inadvertent or intentional damage to the fuel bladder and the fuel contained therein.

In another embodiment of the present invention shown in FIG. 15, removable fuel cartridge 39e is similar to the removable fuel cartridges described above, but includes two spring plates 138e and 139e in place of the foam pressure member. Like reference numerals have been used to describe like components of removable fuel cartridge 39e as described above.

As shown in FIG. 15, removable fuel cartridge 39e generally includes an expandable fuel bladder 86e, a pair of spring plates 138e and 139e, and a sealable exit port 88 e. In this embodiment, leaf spring member 140e is integral with spring plates 138e and 139 e. Preferably, the spring plate is constructed of steel, but it should be understood that the spring plate may be constructed of other suitable materials having an inherent memory. In the illustrated embodiment, 4 leaf spring members are provided per spring plate, thereby providing a structure capable of applying higher transmission pressure to the fuel bladder. In addition, the multiple leaf spring configuration may provide a more uniform pressure at which fuel is dispensed from the fuel bladder. It should be understood that one, two, three, four or more leaf springs may be used according to the invention.

Removable fuel cartridge 39e includes a rigid container 92e constructed of polycarbonate and/or other suitable material. Container 92e includes two container portions 95e and 96e that are permanently secured to one another by permanent bonding, welding, and/or other suitable means such that the container permanently houses expandable fuel bladder 86e and expandable pressure member 87 e.

The permanently affixed configuration of the container components promotes the overall safety of the fuel cartridge, as well as the safety of the fuel cell assembly and the portable electronic device in which it is used, since this configuration prevents inadvertent or intentional damage to the fuel bladder and the fuel contained therein. Thus, the permanent sealing structure of the container components also prevents misuse of the fuel cartridge by contacting and misusing the fuel contained therein.

In another embodiment of the present invention shown in FIG. 16, removable fuel cartridge 39f is similar to the removable fuel cartridges described above, but includes an air filter and/or Ion Exchange Column (IEC) within the fuel cartridge. Like reference numerals have been used to identify like components of removable fuel cartridge 39f and the removable fuel cartridges described above.

Although not shown in FIG. 16, removable fuel cartridge 39f generally includes an expandable fuel bladder, a pressure member, and an outlet similar to those described above. In this embodiment, removable fuel cartridge 39f includes a rigid container 92f constructed of polycarbonate and/or other suitable material. The container 92f includes two container portions 95f and 96f that define a main chamber 145 for receiving and housing the inflatable bladder and pressure member in the same manner as described above. The container portions 95f and 96f also define an auxiliary chamber 146 that is sized and configured to receive additional components such as, but not limited to, an air filter, a fuel filter, an ion exchange column, a fan, a pump control chip, a metering valve, a metering pump, a membrane, a water absorbent, a carbon dioxide absorbent, and/or a methanol absorbent, which is indicated by reference numeral 148. For example, an air filter may be provided for purifying the air stream, and an IEC may be provided for purifying the methanol supplied to the fuel cell. Such additional components, such as filters, fans, pumps, ion exchange columns, etc., may be serviceable items that often require replacement. By incorporating such add-on components into the fuel cartridge, the durable add-on components are automatically replaced each time a new fuel cartridge is installed in a portable electronic device, such as a cellular telephone.

Container portions 95f and 96f are permanently secured to one another by permanent adhesives, welding, and/or other suitable means such that the container permanently houses expandable fuel bladder 86f and expandable pressure members 87f, as well as additional components 148.

In another embodiment of the present invention shown in FIG. 17, removable fuel cartridge 39g is similar to the removable fuel cartridges described above, but includes a pump 149 and/or pump control chip 150 within the fuel cartridge. Like reference numerals have been used to identify like components of removable fuel cartridge 39g and the removable fuel cartridges described above.

Although not shown in FIG. 17, removable fuel cartridge 39g generally includes an expandable fuel bladder and an outlet, similar to those described above. In this embodiment, removable fuel cartridge 39g includes a rigid container 92g constructed of polycarbonate and/or other suitable material. Container 92g includes two container portions 95g and 96g and houses an inflatable bladder in the same manner as described above.

Pump 149 may or may not be integral with outlet 88 g. The pump 149 may also be configured to supplement the force exerted on the bladder by the inflatable pressure member and/or the spring plate. Alternatively, the pump 149 may be used in place of the inflatable pressure member and/or the spring plate. For example, a positive displacement pump may be used to deliver fuel within the bladder to the fuel cell in a controlled manner. Various pumps may be used in accordance with the present invention, including but not limited to piezo-ceramic micropumps produced by StarMicronics America of Edison, N.J..

The pump 149 is of a type designed to minimize size and dimensions. The reliability and useful life of such pumps is often sacrificed by compact designs. Since the service life of such a pump is typically one or two hundred hours, the pump would be considered a durable item. Pump control chip 150 can be configured to store data relating to the use of the pump, whereby the chip can be used to determine the amount of fuel consumed and/or the amount of fuel remaining in the fuel bladder (e.g., a fuel gauge). The size and shape of the pump control chip 150 can be minimized at the expense of the lifetime and reliability of the control chip, and thus, can also be considered a durable item in the same manner as the additional components described above. By incorporating such serviceable items in the fuel cartridge, the serviceable items are automatically replaced, in the same manner as the supplemental component 148 described above, each time a new fuel cartridge is installed.

Container portions 95g and 96g are permanently secured to one another by permanent adhesives, welding, and/or other suitable means such that the container permanently houses expandable fuel bladder 86g and expandable pressure members 87g, as well as pump 149 and/or pump control chip 150.

In another embodiment of the present invention shown in FIG. 18, removable fuel cartridge 39h is similar to the removable fuel cartridges described above, but includes an air filter and/or Ion Exchange Column (IEC) and a fan within the fuel cartridge. Like reference numerals have been used to identify like components of removable fuel cartridge 39h and the removable fuel cartridges described above.

Although not shown in FIG. 18, removable fuel cartridge 39h generally includes an expandable fuel bladder, a pressure member and an outlet similar to those described above. In this embodiment, removable fuel cartridge 39h includes a rigid container 92h formed of polycarbonate and/or other suitable material. The container 92h includes two container portions 95h and 96h that include a main chamber 145h for receiving and housing the inflatable bladder and pressure member in the same manner as described above. The container portions 95h and 96h also define an auxiliary chamber 146g that is sized and configured to receive an additional component 148g and/or a fan 153 or other suitable blowing device. The fan 153 is of a type designed to minimize size and dimensions. The reliability and useful life of such pumps, which may also be considered durable, are often sacrificed by the compact design. By incorporating such serviceable items, such as filters and/or fans, into the fuel cartridge, these serviceable items are automatically replaced, each time a new fuel cartridge is installed.

Container portions 95h and 96h are permanently secured to one another by permanent adhesives, welding, and/or other suitable means such that the container permanently houses expandable fuel bladder 86h and expandable pressure members 87h, as well as additional components 148h and fan 153.

The fuel cell assembly of the present invention may be configured to recover water from the cathode exhaust stream, which may be used to replenish the anode side of polymer electrolyte membrane 53. In one embodiment, the fuel cell assembly or removable fuel cartridge includes a water recovery system 155 or a portion of such a system, such as that shown in FIG. 19, which includes a two-way heat exchanger 156 and a condenser/radiator heat exchanger 157 fluidly connected in series so that the cathode exhaust is supplied to the recovery loop and a portion of the exhaust water is returned to replenish the anodes. In this embodiment, the condenser/radiator heat exchanger 157 includes one condenser and one radiator arranged back-to-back so as to allow the exhaust water to flow cross-wise with the cooling air. In the illustrated embodiment, 40 ℃ air is used to cool the exhaust water 20 ℃ as it passes through the heat exchanger, however, it should be understood that the actual temperature and amount of cooling will depend on the particular fuel cell assembly. As shown in fig. 19, a part of the water of lower temperature discharged from the condenser/radiator heat exchanger 157 flows through the two-way heat exchanger 156, thereby adjusting the temperature of the recovered water before the recovered water reaches the anode side of the membrane electrode assembly 33. It should be understood that the configuration of the system 155 may vary depending on various factors including the temperature of the discharged water and the desired temperature of the recovered water.

In one embodiment, the fuel cell assembly 31i of the present invention may employ a liquid/gas separator 158 for separating gas and liquid in the cathode and/or anode exhaust streams, as shown in fig. 20. For example, a cyclone, centrifugal separator, and/or other suitable device may be used to separate methanol, water, and/or other liquids from the gas.

Also shown in fig. 20, fuel cell assembly 31i may include a separator membrane 159 between cathode exhaust 160 and anode loop 161 to keep the anode liquid separate from the cathode exhaust, to transfer heat from the cathode exhaust to the anode liquid, and/or to transfer water from the cathode exhaust to the anode loop due to the difference in concentration on each side of the membrane. It should be understood that the barrier membrane may include a permeable membrane and/or other suitable device.

In one embodiment, the fuel cell assembly of the present invention may utilize a pressure differential between the water recovered from the cathode and the anode loop. A positive pressure differential between the cathode feed water and the anode loop may be created by the pump 149 and the water injection point 162 of the anode loop may be at the inlet of the anode pump, which is the lowest pressure point in the anode loop. An extractor 163 in the anode loop may be used to create a local pressure point to accelerate the flow of fluid from the methanol source and/or water source to a lower pressure. Negative pressure may also be applied to the anode circuit to control the rate of fluid change. The negative pressure may also provide a driving force for injecting methanol from a bladder contained in the vented cartridge as shown in FIG. 7.

It should be understood that various methods related to methanol-water mixing may be used in accordance with the present invention, including but not limited to: a reference cell 164 (see fig. 20) is used in the fuel cell to control the methanol concentration in the anode loop; proportional injection, whether passive or active, is used, controlled by a microprocessor control system (e.g., pump control chip 150, FIG. 17); using injectors, each sized to maintain a fixed flow rate of water and methanol (e.g., injector 163); and using a look-up table 165 in which a number of parameters are measured and the degradation in performance is assumed to be due to a decrease in methanol concentration in the anode fluid.

It should be understood that various methods for removing water may be used in accordance with the present invention. For example, an evaporation method may be used in which waste water is evaporated into air having a higher temperature than ambient air due to heat transfer from the fuel cell system. In this embodiment, the cathode product water will be dripped, sprayed or wicked onto a large surface area with a highly permeable matrix. Alternatively, a condensation method may be used. Product water may be condensed and the cathode exhaust gas produced thereby saturated with water at a reduced temperature and then either reheated and released into the surrounding atmosphere or discharged into a cooled air stream. Alternatively, the water is left in the spent fuel cartridge. This will take advantage of the empty volume of the fuel cartridge that is created when the fuel is spent. In this approach, first flexible bladder 86j will contain methanol, while second flexible bladder or add-on 166 in fuel cartridge 39j will receive excess cathode water, as shown schematically in FIG. 21. Such a fuel cartridge would preferably be vented to atmosphere (e.g., via opening 167).

In addition to the above, product water or wastewater produced at the cathode can diffuse back through the polymer electrolyte membrane (e.g., PEM 53j, fig. 20) to replenish water consumed at the anode. This would require temperature control as well as control of the permeability and thickness of the polymer electrolyte membrane.

An alternative fuel sensor is also shown in the embodiment shown in fig. 20. Fuel cell assembly 31i may be provided with a fuel sensor 168 to monitor the concentration of fuel in the anode fuel circuit. In one embodiment, fuel sensor 168 is a methanol sensor that includes a sensor membrane 169 that is partially permeable to methanol and is positioned in contact with the anode fuel circuit. Methanol passes through the sensor membrane 169 to a catalyst layer 170 to which a thermocouple 171 is attached. It should be understood that other devices may be used to determine temperature, including, but not limited to, infrared detectors, thermistors, and other suitable devices. The temperature at thermocouple 171 is measured and compared to a reference temperature. The change in temperature is dependent on the amount of heat generated by the reaction of methanol at the catalyst layer 170, which is proportional to the concentration of methanol in the anode fuel circuit.

The sensor membrane 169 preferably includes a small amount of a suitable catalyst in contact with the methanol permeable membrane. For example, PtRu black and/or other suitable catalysts can be deposited onto NAFION or other suitable films. The fuel sensor is configured such that air can be easily supplied to the catalyst layer 170 and carbon dioxide and water are allowed to be discharged from the sensor catalyst layer 170. When the front surface of the sensor membrane is in contact with a methanol solution, in this case, fuel, a large amount of methanol proportional to the methanol concentration of the fuel solution, permeates the sensor membrane and reacts with the catalyst in the presence of air according to the following reaction formula:

reaction formula (1)

The methanol/catalyst reaction generates heat, which is measured as a temperature rise at thermocouple 171 in intimate contact with catalyst layer 171. In one embodiment, the sensor membrane responds to methanol concentrations of 0.5 to 3 molar to achieve a stable temperature differential reading within two minutes.

It should be understood that the sensor catalyst may be provided in a variety of configurations. For example, the sensor catalyst may be coated on the back side of the permeable sensor membrane, in the form of a small amount of free-floating powder, and/or coated on a separate substrate and placed behind the sensor membrane. The method of delivering methanol to the catalyst can be any method of delivering vapor, liquid methanol, or methanol solution, so long as the amount delivered is proportional to the concentration in the anode fuel circuit. For example, a small portion of the fuel may be capillary absorbed or pumped to the sensor area. The fuel sensor may be provided on a wall of the reservoir or as a side arm attachment to the fuel flow circuit.

In one embodiment, the fuel sensor is configured to measure a reference temperature and measure a temperature difference between the sensor temperature and the reference temperature to meet a requirement that the fuel cell generally cannot operate at a single absolute temperature. For example, the reference temperature may be a fuel temperature near the membrane.

Since the rate of methanol permeation through an ion-conducting membrane is also known to be temperature dependent, it is desirable for the fuel cell to operate at a constant reference temperature, or more desirably to have its response calibrated within a desired operating temperature range.

Operation of the fuel sensor in close proximity to the methanol solution may favor fully hydrated conditions of the membrane as compared to the headspace in the reservoir. Such conditions of complete hydration are desirable because the methanol permeability of a given membrane is generally sensitive to the degree of hydration of the membrane.

It should be understood that the fuel sensor of the present invention is not limited to methanol fuel, nor to fuel cells. For example, the concentration of any chemical that can permeate through the membrane and readily oxidize at the catalyst surface giving off heat can also be measured in the manner described above.

In one embodiment, the fuel cell assembly is configured to indirectly determine an initial fuel concentration within the fuel cell cartridge. The united states department of transportation has enacted a regulation where fuel containers containing less than the initial 24% methanol concentration can be used for air transport, for example, on commercial aircraft to provide power for electronic devices. In other applications, cartridges containing higher than initial methanol concentrations may be used.

To indirectly identify the concentration of the fuel, removable fuel cartridge 39 is configured so that the concentration of methanol fuel in the fuel cartridge can be automatically identified by fuel cell assembly 33. In this embodiment, a suitable identification device 172 is used to identify the fuel cartridge, which can be easily read by the fuel cell assembly. Such identification means may or may not be incorporated into the main power consuming apparatus, such as the portable electronic device 32.

In one embodiment shown in FIG. 21, removable fuel cartridge 39 includes optical indicia 172 similar to indicia identifying a 35mm membrane cartridge ASA grade, thereby allowing the fuel cell assembly to determine the fuel concentration in removable fuel cartridge 39 by reading such optical indicia when the fuel cartridge is loaded into a portable electronic device or fuel cell assembly. In another embodiment, the features are provided on the fuel cartridge housing that are readable mechanically (e.g., using mechanical switches), electronically (e.g., via Hall effect, an integrated circuit chip, or other electronic device), and/or by other suitable means.

The fuel identification structure of the present invention may be configured to enable the fuel cell assembly to determine the methanol concentration in the fuel container, from which various operating parameters may be determined, including metering ratio, run time, size and concentration of the fuel container. The identification information of the fuel cartridge may also include other information including manufacturing lot size, date of manufacture, expiration date, manufacturer, and/or other desired information.

Advantageously, the identification system of the present invention will allow a user of a portable electronic device to carry a fuel cartridge containing an initial 24% methanol concentration for air travel and for use in airline travel, and also allow the user to use fuel cartridges containing higher concentrations of methanol fuel at other times. The ability to use high concentration methanol fuel cartridges increases the run time of devices using fuel cartridges powered by direct methanol power generation. The ability to carry multiple cartridges (i.e., less than 24% strength) for air travel authentication allows a user to extend the time to operate a portable electronic device by using multiple cartridges.

The identification structure of the present invention allows for the standardization of replaceable fuel cartridges that can be used in a variety of fuel cell applications including, but not limited to, portable electronic devices that utilize direct methanol power generation. Generally, known fuel cell assemblies are limited in methanol concentration suitable for conventional polymer electrolyte membranes such as NAFION membranes manufactured by DuPont. At high concentrations, the polymer electrolyte membrane and the corresponding fuel cell will suffer from corrosive effects, which may reduce the performance and/or durability of the fuel cell power plant. Known fuel cell assemblies do not have suitable sensor technology for monitoring methanol concentration in the fuel cell power plant. Thus, the identification of the structure of the present invention enables the fuel cell assembly to monitor the input concentration, that is, the initial fuel concentration of the replaceable fuel cartridge. A controller (e.g., controller 173, fig. 20) of the fuel cell assembly can make appropriate adjustments to control operating parameters of the fuel cell assembly to maintain an appropriate methanol concentration in the fuel cell assembly, thereby mitigating or eliminating the negative effects of an inappropriate fuel concentration.

The identification of the structure of the present invention also allows for the technological advancement of fuel cell polymer electrolyte membranes without altering the design of the fuel cartridge. Such membrane technology continues to advance, which allows for the use of higher concentrations in the fuel cell itself. As such advances have evolved, it has become preferable to continue to use existing fuel cartridges at a later time as such advances are brought into consumer products. The ability of the fuel cell power plant to determine the fuel concentration allows for later continued use of the replaceable fuel cartridge of the present invention.

The supply of fuel from the fuel reservoir to the fuel cell assembly according to the present invention may be achieved in a number of ways. In one embodiment, the fuel bladder may be pressurized, such as using expandable pressure members 87 as shown in FIG. 7, or other suitable means, and metering valve 174 is used to provide the desired amount of fuel to the fuel cell assembly. It should be understood that a metering pump may be used instead of or in addition to the metering valve. Alternatively, the pressureless bladder may be used in conjunction with a positive displacement pump, such as pump 149 shown in FIG. 17.

In one embodiment, the fuel cell assembly is configured to accommodate freeze tolerance during shutdown. Upon shutdown, portions of the fuel cell assembly may experience a significant drop in temperature, approaching the freezing point of water. If the fuel cell assembly includes a water source (i.e., water source 175 in fig. 20), the fuel cell assembly may be configured to prevent freezing of water in the fuel circuit by increasing the methanol concentration in the fuel circuit beyond a predetermined level to prevent a phase change of the fuel/water mixture in the fuel circuit. For example, the controller may actuate a metering valve, pump, or other suitable device to increase the methanol concentration in the fuel circuit beyond about 8 moles to prevent such phase changes. Alternatively, the pump may be caused to substantially remove liquid water and/or other fluids from the fuel circuit.

In one embodiment, the fuel cell assembly may be configured to circulate the fuel circuit through a reservoir of pure methanol, as shown in fig. 22. The anode loop 161 is in fluid communication with a fuel reservoir 176 containing methanol, preferably 100% methanol. The methanol diffusion membrane 177 is located between the inlet and outlet of the methanol fuel reservoir 176, with each port containing a shut-off valve. The diffusion membrane is configured to allow methanol to enter the anode loop, but prevent water from diffusing into the fuel reservoir. A bypass loop 178 is provided to allow anode fluid flow when the methanol container is outside the anode loop. During shutdown, the inlet and outlet to the methanol vessel are opened to allow diffusion of methanol into the anode loop to a suitable level to prevent freezing.

In one embodiment, the fuel cell assembly is provided with a temperature sensor (see, for example, thermocouple 171 in figure 20) and is configured to prevent the fuel cell assembly from starting below a certain temperature. For example, if the temperature is below 32 ° F, the fuel cell assembly is configured to prevent startup so as to prevent damage to the assembly in the event that water freezes within the assembly. Preferably, the fuel return valves are physically adjacent to the inlet and outlet to the membrane electrode assembly 33i (see preferred location 179 as shown in FIG. 20) to prevent diffusion of excess fuel fluid through the assembly (e.g., polymer electrolyte membrane 53 i).

In one embodiment shown in FIG. 20, the fuel cell cartridge contains fuel and liquid water storage media 176 and 175, respectively. In this embodiment, the cathode exhaust gas containing water is treated to liquefy the water vapor. In this regard, a condenser 180 is provided to liquefy the water vapor. The non-liquefied water vapor is then absorbed or stored through a portion of the fuel cartridge for replenishment into the anode loop.

Waste carbon dioxide generated by the fuel cell assembly may be utilized in accordance with the present invention. For example, excess carbon dioxide may be supplied to the fuel cartridge 39k container having a second chamber 146k defined in part by movable piston wall 181 and having a relief valve 182 for maintaining a pressure of about 1-2psi to facilitate fuel flow from the flexible fuel bladder, as shown in FIG. 23. In particular, the pressure in the second chamber will remain at a relatively low pressure that will cause the piston wall 181 to apply a slight bias to the fuel bladder 86 k. Thus, spent carbon dioxide may be used to provide a positive pressure on fuel bladder 86k within fuel cartridge 89 k. It will be appreciated that an additional bladder may be substituted for the piston structure to provide an expandable chamber fed by excess carbon dioxide which can provide positive pressure to the fuel bladder. Alternatively, spent carbon dioxide may be used to drive a circulation pump to generate power to increase fuel cell efficiency and/or other expansion devices may alternatively be used, such as reciprocating solenoids or valves of a fuel pump.

Other uses of the carbon dioxide off-gas include discharging it to the cathode for oxidation of the CO contained therein₂Methanol vapor in the exhaust gas and CO₂And discharged to the cathode chamber to remove oxygen and prevent methanol in the cathode chamber from burning after shutdown.

In another cartridge embodiment shown in FIG. 24, two ports pass all or part of the anode loop 161l through a fuel filter 183 contained in the replaceable cartridge 184. It will be appreciated that such filters may have a limited useful life and may require periodic replacement. Advantageously, the provision of a filter in a replaceable fuel cartridge allows the fuel filter to be automatically replaced with each replacement of the replaceable fuel cartridge. In one embodiment, the fuel filter is an organic filter, however, it should be understood that any other suitable filter arrangement may be used. Alternatively, a third port of replaceable cartridge 184 is in fluid communication with methanol in the fuel cartridge to provide methanol to the anode circuit via metering valve 174l in the cartridge. The metering valve may be controlled by a system actuator 185 within the body of the fuel cell assembly or by an actuator (not shown) located within the replaceable fuel cartridge.

In an alternative embodiment shown in fig. 25, only two ports are included in the fuel cell cartridge. One port communicates with the fuel cell circuit to allow the circuit to flow into the fuel cartridge, while the other port provides communication with the fuel circuit to return the fuel flow. The fuel in the fuel cartridge is in fluid communication with the interior of the fuel cell circuit within the cartridge. The flow of fuel to the fuel cell circuit is controlled by a metering valve 174 in the cartridge that is controlled by a system actuator 185 located in the fuel cell body and operatively connected to a controller (e.g., controller 173).

In other embodiments of the present invention, injector assembly 186 having a fuel chamber 187 may be provided in conjunction with or in place of a replaceable fuel cartridge. The injector assembly may have a variety of configurations including, but not limited to, a refillable injector 188, a replaceable injector 189, an internal injector 190, and a replaceable cartridge 191, as shown in fig. 26(a) -26 (d), respectively. In the first three categories, the fuel reservoir is permanently placed in the portable electronic device. Various forms of injector assemblies are used to transfer fuel from the refill container to a reservoir located on the electronic device and/or replaceable fuel cartridge, alternatively the injector may be located within the electronic device.

In one embodiment shown in FIG. 27, the refillable syringe 188 includes an injection valve 192 fluidly connected to the syringe pump 149r and selectively coupled to the refilling cartridge 193. The refill cartridge may be in the form of a plastic container, however, it will be appreciated that other suitable containers and/or materials may be used. When the refill cartridge is inserted into the refillable injector 188, the refill valve 194 opens, thereby allowing fuel cell fuel to be drawn from the refill cartridge 193 through the refillable injector 188. A syringe pump, which may be activated by a syringe control switch 195 located on the outer surface of the syringe, is used to draw fluid from the refill cartridge and transfer it to the portable electronic device. In one embodiment, the syringe pump is powered by a syringe battery 196 and controlled by a syringe pump control board 197. The control panel may be configured to detect when the fuel level of the portable electronic device is full, thereby deactivating the pump to prevent overfilling the portable electronic device with fuel. The control board may monitor the fuel level by monitoring back drive on the pump, by using a pressure sensor provided on the refillable injector, by a pressure sensor provided on the portable electronic device, and/or other suitable means.

In another embodiment shown in FIG. 28, the refillable syringe 188s is a spring-loaded syringe assembly that includes a refilling cartridge 193s sealed by a cartridge valve 194s and a syringe piston 198. The refill cartridge may be engaged with the refillable syringe in any suitable manner. For example, the refill may be inserted into the refillable syringe and twisted to lock the refill cartridge into the refillable syringe. When the reloadable injector 188s is attached to the portable electronic device, the cartridge valve automatically opens and fuel can be transferred from the reloadable cartridge 193s to the fuel cell assembly. An injector spring 199 may be used to bias the piston toward the refill valve, thereby providing a positive pressure on the fuel to drain the fuel from the refill cartridge/refillable injector assembly. In another embodiment shown in FIG. 29, the replaceable injector 189 further includes an injector spring 199t and a plunger 198t, but does not include a separate replaceable refill cartridge, thereby providing a simpler but replaceable structure.

Advantageously, the spring-loaded syringe is cheap and easy to manufacture. The refill cartridges may be mass produced in a similar manner to known insulin refill cartridges. Moreover, such spring-loaded injectors are simple to operate and allow for automatic dispensing of fuel upon insertion into a portable electronic device.

In another embodiment shown in FIG. 30, refillable injector 188u includes a replaceable refill cartridge 193u that is also sealed by injection valve 192u and injector piston 198 u. In this embodiment, the refill cartridge is threadably engaged with the injector assembly, however, it should be understood that other engagement means may be used, including, but not limited to, the twist-and-lock arrangement described above. In this embodiment, when the refillable injector is attached to the portable electronic device, the injector valve automatically opens and fuel can be transferred from the refill to the portable electronic device. An injector motor 200 and an injector driver 201 may be activated to bias the piston toward the injector valve, thereby emptying the contents of replaceable refill cartridge 193u into the fuel cell assembly of the portable electronic device. In the illustrated embodiment, the injector device is a lead screw assembly, however, it should be understood that other suitable devices may be used. By monitoring the back-drive of the injector motor, the refillable injector can detect when the fuel cell assembly is full and stop the refilling process. Alternatively, a pressure sensor may be used in a manner similar to that described above to detect when the fuel cell assembly is full and stop the recharging process.

In another embodiment shown in FIG. 31, the refillable injector 188v comprises a replaceable refill cartridge similar to that described above, but includes a manually actuated injector drive assembly. Specifically, the syringe drive assembly 201v is actuated by a manually operated knob to cause the lead screw 201v to move the syringe cartridge 203 upward, thereby biasing the syringe piston 198v toward the syringe valve 192v, emptying the contents of the refill cartridge into the portable electronic device. An injector slip clutch 204 may be provided to stop the movement of the piston when the electronics are full of fuel. The refill cartridge and injector assembly may be threadably engaged as described above, however, it should be understood that other suitable engagement means may be used. It should also be understood that the injector drive structure may be used not only in a refillable injector assembly but also with a replaceable injector assembly in accordance with the present invention.

In another embodiment shown in fig. 32, the syringe assembly is similar to that described above, but includes a manual pump assembly 205. For example, a refillable injector 188w or a disposable injector 189w may include a fuel chamber 187w sealed by injector valve 192w and flexible membrane or diaphragm 206. In the illustrated embodiment, the manual pump assembly is a thumb-actuated pump, similar to that found on REEBOK sneakers, that is used to provide a positive pressure on the flexible diaphragm that can be used to transfer fuel from the syringe assembly into the portable electronic device. A pressure relief valve 207 may be provided to prevent excessive pressure from being exerted by the user on the syringe assembly and/or the portable electronic device. The pressure relief valve and/or other components of the syringe assembly may also be configured to provide an audible indication when filling is complete. It should be understood that a manual pump assembly may also be used in the disposable syringe assembly 189x shown in fig. 33.

In another embodiment, an internal injector assembly 190 is provided that has all of the functionality of the refillable and replaceable injector assembly described above, but is located inside the portable electronic device, as shown in FIG. 34. Advantageously, such a configuration may help reduce the size, cost and complexity of the refill cartridge, and may also prevent the application of excessive pressure. In this embodiment, the portable electronic device 32y includes a fuel reservoir 208 having a one-way fill valve 209 to allow refilling. Once the refill cartridge 193 is engaged with the injection valve and in fluid communication with the fuel reservoir, the injection lever 210 can be depressed to expand the fuel chamber, thereby creating a negative pressure therein that can draw fuel from the refill cartridge. Once the fuel is added, that is, once fuel chamber 208 is substantially full, by depressing the lever, fuel chamber spring 211 is compressed to create a positive pressure in the fuel circuit of the fuel cell assembly capable of pumping fuel from the fuel reservoir to the portable electronic device. In this regard, it should be understood that the fuel cell spring functions in the same manner as the expandable pressure member 87 described above. In another embodiment, the fuel reservoir 208z may include a bladder in the form of a bellows 212, which may further enhance the retention of fuel in the fuel reservoir, as shown in FIG. 35. It should be understood that the bellows may be used in conjunction with a circular plunger or a rectangular piston.

It should be understood that other suitable bladder configurations may be used in accordance with the present invention. In the embodiment shown in fig. 36(a), the bladder 212aa may be disposed between and used in conjunction with two lateral compression plates 213 as shown in fig. 36(a), which exert pressure against each other through springs to thereby provide positive pressure on the bladder in a manner similar to compression plates 138 and 139 described above. Alternatively, the compression plates 213bb may be provided with interconnecting connecting rods 214, causing the compression plates to apply pressure to each other by coil springs, as shown in fig. 36 (b). Further, the compression plates 213cc may be pivotally connected by a hinge, in which the compression plates apply pressure to each other by coil springs, as shown in fig. 36 (c).

It should be understood that one, two, three or more fuel injectors, reloading cartridges, and/or fuel reservoirs may be used in accordance with the invention. For example, as shown in FIG. 37, a plurality of syringes 215 may be used to draw fluid from the syringe assembly and/or the refill cartridge in a manner similar to that described above. Multiple syringes may be used to achieve the increase in volume that may be required for larger portable electronic devices such as laptop computers and other equipment that use fuel cell assemblies.

In one embodiment, as shown in FIG. 38, the removable fuel cartridge is provided with a main chamber 145ee enclosing an expandable fuel bladder 86ee which is in fluid communication with an inlet on the anode side of the fuel cell assembly in a manner similar to that described above. In this embodiment, an absorber 216 is located in the second chamber 146 ee. In one embodiment, the device 216 is an annular tubular member comprising a latex tube 217 surrounding a porous material 218 and filled with a desiccant 219. The porous material may comprise a screen, a permeable membrane and or other suitable means that allows selective passage of water and/or other substances to be absorbed. If water is the target substance to be absorbed, the desiccant may include acrylic acid, carrageenan, and/or other materials suitable for absorbing water. It should be understood that other desiccants may be used to absorb other target substances, including, but not limited to, carbon dioxide and methane. It should also be understood that an irreversible absorbent or a reversible absorbent may be used as the desiccant.

In the embodiment shown in fig. 38, the absorber 216 is fluidly connected to an exhaust port on the cathode side of the fuel cell chamber and is configured to receive water and air exhausted from the cathode. In this embodiment, the absorption apparatus is configured to capture or absorb water in the exhaust gas stream. Such a water absorbing structure is particularly advantageous for removing water from the exhaust gas stream when the exhaust air is utilized by the cathode, since water will be removed from the fuel cell fluid circuit and thus will increase the freeze resistance of the fuel cell assembly.

In various aspects, like reference numerals, similar to the previous modifications, and like reference numerals preceded by the subscripts "a" through "ee" designate corresponding parts throughout the various views.

The foregoing descriptions of specific embodiments of the present invention are presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. The scope of the invention herein is defined by the appended claims and equivalents thereof.

Claims (22)

1. A removable fuel cell cartridge for a liquid fuel cell assembly comprising:

a container having a first fuel chamber with at least one port for delivering fuel to the fuel cell assembly; and

a second chamber for one or more additional components, wherein the second chamber comprises at least two ports, wherein at least one port is in communication with the fuel cell assembly.

2. The fuel cartridge of claim 1 wherein said first chamber and said second chamber are separated by a stationary divider.

3. The fuel cartridge of claim 1 wherein said additional component is selected from the group consisting of an air filter, a fuel filter, an ion exchange column, a fan, a pump control chip, a metering valve, a metering pump, a membrane, a water absorbent, a carbon dioxide absorbent, and a methanol absorbent.

4. The fuel cartridge of claim 1 wherein said container has a proximal end engaged with said fuel cell assembly and a distal end opposite said proximal end, wherein each of said first and second chambers is located between said proximal and distal ends of said container.

5. The fuel cartridge of claim 1 wherein said container has a proximal end engaged with said fuel cell assembly and a distal end opposite said proximal end, wherein said first chamber is located adjacent said proximal end and said second chamber is located adjacent said distal end.

6. The fuel cartridge of claim 1 wherein said container has a proximal end engaged with said fuel cell assembly and a distal end opposite said proximal end, wherein said second chamber is located adjacent said proximal end and said first chamber is located adjacent said distal end.

7. The fuel cartridge of claim 6 wherein said second chamber includes a metering valve or a metering pump in fluid communication with said first chamber through a first port, wherein said second chamber includes a second port in fluid communication with an anode loop of said fuel cell assembly.

8. The fuel cartridge of claim 7 wherein said fuel metering valve or metering pump is controllable by an actuator located within said fuel cell assembly.

9. The fuel cartridge of claim 6 wherein said second chamber includes an inlet and an outlet for fluid communication with an anode loop of said fuel cell assembly, a fluid connector between said inlet and outlet, and a metering valve or a metering pump in fluid communication with said first chamber and said fluid connector.

10. The fuel cartridge of claim 9 wherein said fuel metering valve or metering pump is controllable by an actuator located within said fuel cell assembly.

11. The fuel cartridge of claim 9 further comprising a fuel filter in said second chamber in fluid communication with said first chamber or said fluid connector.

12. The fuel cartridge of claim 9 further comprising an ion exchange resin in fluid communication with said first chamber or said fluid connector.

13. The fuel cartridge of claim 9 wherein said second chamber includes an inlet port and an outlet port for fluid communication with the anode loop of said fuel cell assembly, a fluid connector between said inlet and outlet ports and a metering valve or a metering pump in fluid communication with said first chamber and a fuel supply port for fluid communication with the anode loop of said fuel cell assembly.

14. A removable fuel cell cartridge for a liquid fuel cell assembly comprising:

a container having a first fuel chamber with at least one port for delivering fuel to the fuel cell assembly; and

an absorbent device having at least two ports, wherein at least one port is in communication with the fuel cell assembly.

15. The fuel cell cartridge of claim 14 wherein said absorbent device is configured to remove water from an exhaust loop of said fuel cell assembly.

16. The fuel cell cartridge of claim 14 wherein said container includes a second chamber and said absorbent means is located in said second chamber.

17. The fuel cell cartridge of claim 16 wherein said first chamber and said second chamber are separated by a stationary separator.

18. The fuel cartridge of claim 14 further comprising one or more additional components selected from the group consisting of air filters, fuel filters, ion exchange columns, fans, pumps, pump control chips, metering valves, metering pumps, membranes, water absorbents, carbon dioxide absorbents, and methanol absorbents.

19. A fuel cell assembly comprising the fuel cartridge of claim 1 or 14.

20. An electronic device comprising the fuel cell according to claim 19.

21. A power supply comprising the fuel cell of claim 19.

22. The power supply of claim 21, comprising a plurality of fuel cartridges.

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