WO2009109865A2

WO2009109865A2 - Self-regulating hydrogen generator for fuel cells and hybrid vehicle power system utilizing the same

Info

Publication number: WO2009109865A2
Application number: PCT/IB2009/005394
Authority: WO
Inventors: Gennadi Finkelshtain; Yuri Katsman; Michael Lerner; Mark Estrin; Eric Torgeman
Original assignee: More Energy Ltd.
Priority date: 2008-03-04
Filing date: 2009-03-03
Publication date: 2009-09-11
Also published as: WO2009109865A3

Abstract

A hydrogen generation device includes a liquid fuel chamber (3), a catalytic hydrogen generation chamber (5), a hydrogen collection chamber (8) and separation elements (9, 7) between these chambers (3, 5, 8). Once a certain hydrogen pressure in the device is reached liquid fuel is substantially prevented from being catalytically converted into hydrogen, whereby the production of hydrogen is stopped until hydrogen is allowed to exit the device to lower the pressure therein. This Abstract is not intended to define the invention disclosed in the specification, nor intended to limit the scope of the invention in any way.

Description

SELF-REGULATING HYDROGEN GENERATOR FOR FUEL CELLS AND HYBRID

VEHICLE POWER SYSTEM UTILIZING THE SAME

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims the benefit of U.S. Provisional Patent Application

No. 61/033,629, filed on March 4, 2008 under 35 U.S.C. § 1 19(e), the disclosure of which is expressly incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0002] The present invention relates to a self-regulating hydrogen generator which is based on the catalytic reaction of one or more substances which results in the formation of hydrogen gas. The hydrogen generator may be used, for example, as hydrogen providing device for a hydrogen-based fuel cell system. The invention is also directed to a method of producing hydrogen gas in a self-regulating manner. The invention also provides for a hybrid vehicle power system which utilizes a fuel cell and a self-regulating hydrogen generator.

2. Discussion of Background Information

[0003] There are several devices which use hydrogen in elemental form for generating electrical, mechanical or thermal energy such as, e.g., fuel cells, internal combustion engines and gas torches. Examples of disadvantages of hydrogen gas are that it is highly flammable and difficult and dangerous to handle. It is therefore desirable to have available a hydrogen gas providing system with which hydrogen gas can be produced while it is consumed, thereby avoiding the need for storing large quantities of hydrogen. Particularly when relatively small hydrogen consuming devices such as, e.g., fuel cells for generating electrical energy for appliances such as portable electronics and the like are used it is even more desirable to have available a hydrogen generation device which is capable of producing hydrogen gas in a self- regulating manner, i.e., a device which produces hydrogen while it is consumed by the hydrogen consuming device and automatically stops producing hydrogen when no hydrogen is consumed (for example, due to the hydrogen consuming device being in a non-operative or turned-off mode). SUMMARY OF THE INVENTION

[0004] The present invention provides a self-regulating hydrogen generation device or system of the type disclosed in US Patent Application No. 1 1/742,801 filed on May 1, 2007, the disclosure of which is hereby expressly incorporated by reference in its entirety. Such devices or systems can be used on any of the vehicle power systems disclosed herein. [0005] The present invention relates to a fuel cell system and/or a self-regulating hydrogen generation device or system which is particularly suitable for use with a solid fuel such as of the type disclosed in related US application Nos. 61/055,677 filed on May 23, 2008 (Attorney Docket No. V34383) and 12/333,747 filed on December 12, 2008 (Attorney Docket No. P35532), the entire disclosure of which are hereby expressly incorporated by reference. [0006] The present invention also relates to a hydrogen generator device or system which can be used in different applications such as, e.g., a vehicle fuel cell power system. The production of hydrogen (H₂) is carried out by catalytical hydrolysis of chemical hydrides or borohydrides. Hydrogen is produced in a device and is then consumed by a fuel cell. The hydrogen generator is preferably a self-regulating (passive) mechanism. The regulation mechanism is of the type that performs a separation phase. That is, the device is capable of allowing fuel and catalyst to interact to create hydrogen and can also regulate and/or stop this interaction when hydrogen ceases to be consumed. This separation can occur by separating the fuel from the catalyst or vice versa. According to the present invention, the separation process can be carried out using different self-regulating methods. Numerous non-limiting embodiments of such devices are disclosed herein.

[0007] According to another aspect of the invention, a hydrogen generator of the type disclosed herein can be used a basic element of hybrid vehicle fuel cell power system (HVFCPS). The HVFCPS can include one or more hydrogen generators, one or more fuel cells, one or more electrical motors and/or electric motor/generator units, and one or more rechargeable battery and/or traction batteries. Such an HVFCPS can provide effective vehicle operation at the different working conditions. In particular, such a system can be particularly beneficially used on a city vehicle because of its ability to produce minimal or zero toxic pollution.

[0008] According to another aspect of the invention, the fuel cell of the present invention is preferably configured to provide constant power and can also serve as one of the main power supply systems for, e.g., a vehicle. This is an optimal regime for fuel cell systems. [0009] According to another aspect of the invention, the battery of system can be recharged by the fuel cell under certain conditions, e.g., when demand for power is reduced, and can supply electricity to the electric motor under certain other conditions, e.g., when demand for power is increased.

[0010] According to another aspect of the invention, the fuel composition which will produce the hydrogen can be in many forms such as, e.g., in solid form, and can be provided in, e.g., a replaceable cartridge. The solid fuel can be activated by a water based dilutant. The byproduct (Spent fuel) can also be collected after usage and regenerated into initial fuel components. One advantage of the invention pertains to the fact that the spent fuel can be substantially free of toxic components.

[0011] According to another aspect of the invention, a self-regulating hydrogen generation device comprises (a) at least one first chamber for holding a liquid and at least one first substance which is a source of hydrogen and is at least partly soluble in the liquid, (b) a catalytic member capable of catalyzing a reaction which involves the at least one first substance and results in the formation of hydrogen gas, and (c) a first separation element which is liquid- permeable and capable of allowing liquid to pass from the first chamber into a second chamber and a second separation element which is substantially liquid-impervious and gas-pervious. [0012] According to another aspect of the invention, the device further comprises a floating member comprising a first separation element which is liquid-permeable and a second separation element which is substantially liquid-impervious and gas-pervious. [0013] According to another aspect of the invention, the device further comprises a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and a second position wherein the liquid does interact with the at least one first substance.

[0014] According to another aspect of the invention, the device further comprises a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the catalytic member and a second position wherein the liquid does interact with the catalytic member.

[0015] According to another aspect of the invention, the device further comprises a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and the catalytic member and a second position wherein the liquid does interact with the at least one first substance and the catalytic member.

[0016] According to another aspect of the invention, the device further comprises a shutter that is movable at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member. [0017] According to another aspect of the invention, the device further comprises a floating member comprising a first a member that moves at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member.

[0018] The liquid may comprise water. The at least one first substance may comprise at least one of a borohydride compound and a metal hydride compound. The at least one first substance may comprise at least one compound selected from NaBH₄, KBH₄, LiBH₄, NH₄BH₄, Be(BKt)₂, Ca(BKt)₂, Mg(BKj)₂, Zn(BKt)₂, Al(BH₄)S, polyborohydrides, (CKS)₃NBH₃, and NaCNBH₃. The at least one first substance may comprise at least one compound selected from compounds of formulae MeH, MeAIH₄ and Me⁵H₂ wherein Me = Li, Na, K and Me' = Be, Mg, Ca, Sr, Ba, Zn. The first chamber may be adapted for holding the at least one first substance in undiluted or concentrated form and, physically separated therefrom, a liquid dilutant for diluting the at least one first substance prior to using the device for the generation of hydrogen. The first chamber may comprise at least two compartments, a first compartment for holding the at least one first substance in undiluted or concentrated form and a second compartment for holding liquid dilutant for diluting the at least one first substance. The first chamber may comprise at least two puncturable or breakable containers, at least one of them holding the at least one first substance in undiluted or concentrated form and at least one of them holding liquid dilutant for diluting the at least one first substance. The catalytic member may comprise at least one of a transition metal in elemental form and a transition metal oxide. The transition metal may be selected from one or more of Pt, Pd, Ru, Rh, Ir, Au, Co, Ni and Fe. The catalytic member may comprise a catalytic substance arranged on a carrier. The carrier may comprise at least one of carbon and a ceramic material. The carrier may be present as at least one of a sheet, a plate, a honeycomb structure, a cylindrical structure and granules. The first separation element may comprise a hydrophilic membrane. The first separation element may have at least one of a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm. The second separation element may comprise a hydrophobic membrane. The second separation element may have at least one of a thickness of from about 20 μm to about 300 μm and a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm. The second separation element may comprise a membrane which has a gas permeability pressure which is not higher than a gas permeability pressure of a membrane which is comprised in the first separation element. The second separation element may have a gas permeability pressure of from about 20 mbar to about 100 mbar. The device may comprise a pressure compensating system. The pressure compensating system may comprise a hydrophobic membrane. The device may further comprise a valve system which can be activated to allow gas to exit the device. At least a part of walls of the first chamber may be flexible. The device may further comprise a water absorption element.

[0019] According to another aspect of the invention, a self-regulating hydrogen generation device comprises (a) at least one first chamber for holding a liquid and at least one first substance which is a source of hydrogen and is at least partly soluble in the liquid, (b) a catalytic member capable of catalyzing a reaction which involves the at least one first substance and results in the formation of hydrogen gas, and (c) a floating member comprising a first separation element which is liquid-permeable and a second separation element which is substantially liquid-impervious and gas-pervious.

[0020] According to another aspect of the invention, the device further comprises a first separation element which is liquid-permeable and capable of allowing liquid to pass from the first chamber into a second chamber and a second separation element which is substantially liquid-impervious and gas-pervious.

[0021] The liquid may comprise water. The at least one first substance may comprise at least one of a borohydride compound and a metal hydride compound. The at least one first substance may comprise at least one compound selected from NaBH₄, KBH₄, LiBH₄, NH₄BH₄, Be(BI-L,)₂, Ca(BH₄J₂, Mg(BH₄J₂, Zn(BH₄J₂, Al(BH₄J₃, polyborohydrides, (CH₃J₃NBH₃, and NaCNBH₃. The at least one first substance may comprise at least one compound selected from compounds of formulae MeH, MeAlH₄ and Me'H₂ wherein Me = Li, Na, K and Me' = Be, Mg, Ca, Sr, Ba, Zn. The first chamber may be adapted for holding the at least one first substance in undiluted or concentrated form and, physically separated therefrom, a liquid dilutant for diluting the at least one first substance prior to using the device for the generation of hydrogen. The first chamber may comprise at least two compartments, a first compartment for holding the at least one first substance in undiluted or concentrated form and a second compartment for holding liquid dilutant for diluting the at least one first substance. The first chamber may comprise at least two puncturable or breakable containers, at least one of them holding the at least one first substance in undiluted or concentrated form and at least one of them holding liquid dilutant for diluting the at least one first substance. The catalytic member may comprise at least one of a transition metal in elemental form and a transition metal oxide. The transition metal may be selected from one or more of Pt, Pd, Ru, Rh, Ir, Au, Co, Ni and Fe. The catalytic member may comprise a catalytic substance arranged on a carrier. The carrier may comprise at least one of carbon and a ceramic material. The carrier may be present as at least one of a sheet, a plate, a honeycomb structure, a cylindrical structure and granules. The first separation element may comprise a hydrophilic membrane. The first separation element may have at least one of a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm. The second separation element may comprise a hydrophobic membrane. The second separation element may have at least one of a thickness of from about 20 μm to about 300 μm and a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm. The second separation element may comprise a membrane which has a gas permeability pressure which is not higher than a gas permeability pressure of a membrane which is comprised in the first separation element. The second separation element may have a gas permeability pressure of from about 20 mbar to about 100 mbar. The device may comprise a pressure compensating system. The pressure compensating system may comprise a hydrophobic membrane. The device may further comprise a valve system which can be activated to allow gas to exit the device. At least a part of walls of the first chamber may be flexible. The device may further comprise a water absorption element.

[0022] According to another aspect of the invention, a self-regulating hydrogen generation device comprises (a) at least one first chamber for holding a liquid and at least one first substance which is a source of hydrogen and is at least partly soluble in the liquid, (b) a catalytic member capable of catalyzing a reaction which involves the at least one first substance and results in the formation of hydrogen gas, and (c) at least one of a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and a second position wherein the liquid does interact with the at least one first substance, a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the catalytic member and a second position wherein the liquid does interact with the catalytic member, and a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and the catalytic member and a second position wherein the liquid does interact with the at least one first substance and the catalytic member.

[0023] According to another aspect of the invention, the device further comprises a first separation element which is liquid-permeable and capable of allowing liquid to pass from the first chamber into a second chamber and a second separation element which is substantially liquid-impervious and gas-pervious.

[0024] The liquid may comprise water. The at least one first substance may comprise at least one of a borohydride compound and a metal hydride compound. The at least one first substance may comprise at least one compound selected from NaBH₄, KBH₄, LiBH₄, NH₄BH₄, Be(BH₄)_J, Ca(BH₄)_Z, Mg(BH₄J₂, Zn(BH₄J₂, Al(BH₄)J, polyborohydrides, (CHs)₃NBH₃, and NaCNBH₃. The at least one first substance may comprise at least one compound selected from compounds of formulae MeH, MeAIH₄ and Me'H₂ wherein Me = Li, Na, K and Me' = Be, Mg, Ca, Sr, Ba, Zn. The first chamber may be adapted for holding the at least one first substance in undiluted or concentrated form and, physically separated therefrom, a liquid dilutant for diluting the at least one first substance prior to using the device for the generation of hydrogen. The first chamber may comprise at least two compartments, a first compartment for holding the at least one first substance in undiluted or concentrated form and a second compartment for holding liquid dilutant for diluting the at least one first substance. The first chamber may comprise at least two puncturable or breakable containers, at least one of them holding the at least one first substance in undiluted or concentrated form and at least one of them holding liquid dilutant for diluting the at least one first substance. The catalytic member may comprise at least one of a transition metal in elemental form and a transition metal oxide. The transition metal may be selected from one or more of Pt, Pd, Ru, Rh, Ir, Au, Co, Ni and Fe. The catalytic member may comprise a catalytic substance arranged on a carrier. The carrier may comprise at least one of carbon and a ceramic material. The carrier may be present as at least one of a sheet, a plate, a honeycomb structure, a cylindrical structure and granules. The first separation element may comprise a hydrophilic membrane. The first separation element may have at least one of a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm. The second separation element may comprise a hydrophobic membrane. The second separation element may have at least one of a thickness of from about 20 μm to about 300 μm and a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm. The second separation element may comprise a membrane which has a gas permeability pressure which is not higher than a gas permeability pressure of a membrane which is comprised in the first separation element. The second separation element may have a gas permeability pressure of from about 20 mbar to about 100 mbar. The device may comprise a pressure compensating system. The pressure compensating system may comprise a hydrophobic membrane. The device may further comprise a valve system which can be activated to allow gas to exit the device. At least a part of walls of the first chamber may be flexible. The device may further comprise a water absorption element.

[0025] According to another aspect of the invention, a self-regulating hydrogen generation device comprises (a) at least one first chamber for holding a liquid and at least one first substance which is a source of hydrogen and is at least partly soluble in the liquid, (b) a catalytic member capable of catalyzing a reaction which involves the at least one first substance and results in the formation of hydrogen gas, and (c) at least one of a shutter that is movable at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member, and a member that moves at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member. [0026] According to another aspect of the invention, the device further comprises a first separation element which is liquid-permeable and capable of allowing liquid to pass from the first chamber into a second chamber and a second separation element which is substantially liquid-impervious and gas-pervious.

[0027] The liquid may comprise water. The at least one first substance may comprise at least one of a borohydride compound and a metal hydride compound. The at least one first substance may comprise at least one compound selected from NaBH₄, KBH₄, LiBH₄, NH₄BH₄, Be(BFLt)₂, Ca(BMt)₂, Mg(BK_t)₂, Zn(BH₄J₂, Al(Bm)₃, polyborohydrides, (CHj)₃NBH₃, and NaCNBH₃. The at least one first substance may comprise at least one compound selected from compounds of formulae MeH, MeAlH₄ and Me⁵H₂ wherein Me = Li, Na, K and Me' = Be, Mg, Ca, Sr, Ba, Zn. The first chamber may be adapted for holding the at least one first substance in undiluted or concentrated form and, physically separated therefrom, a liquid dilutant for diluting the at least one first substance prior to using the device for the generation of hydrogen. The first chamber may comprise at least two compartments, a first compartment for holding the at least one first substance in undiluted or concentrated form and a second compartment for holding liquid dilutant for diluting the at least one first substance. The first chamber may comprise at least two puncturable or breakable containers, at least one of them holding the at least one first substance in undiluted or concentrated form and at least one of them holding liquid dilutant for diluting the at least one first substance. The catalytic member may comprise at least one of a transition metal in elemental form and a transition metal oxide. The transition metal may be selected from one or more of Pt, Pd, Ru, Rh, Ir, Au, Co, Ni and Fe. The catalytic member may comprise a catalytic substance arranged on a carrier. The carrier may comprise at least one of carbon and a ceramic material. The carrier may be present as at least one of a sheet, a plate, a honeycomb structure, a cylindrical structure and granules. The first separation element may comprise a hydrophilic membrane. The first separation element may have at least one of a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm. The second separation element may comprise a hydrophobic membrane. The second separation element may have at least one of a thickness of from about 20 μm to about 300 μm and a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm. The second separation element may comprise a membrane which has a gas permeability pressure which is not higher than a gas permeability pressure of a membrane which is comprised in the first separation element. The second separation element may have a gas permeability pressure of from about 20 mbar to about 100 mbar. The device may comprise a pressure compensating system. The pressure compensating system may comprise a hydrophobic membrane. The device may further comprise a valve system which can be activated to allow gas to exit the device. At least a part of walls of the first chamber may be flexible. The device may further comprise a water absorption element.

[0028] According to another aspect of the invention, a self-regulating hydrogen generation device comprises (a) at least one first chamber for holding a liquid and at least one first substance which is a source of hydrogen and is at least partly soluble in the liquid, (b) a catalytic member capable of catalyzing a reaction which involves the at least one first substance and results in the formation of hydrogen gas, and (c) at least one of: a first separation element which is liquid-permeable and capable of allowing liquid to pass from the first chamber into a second chamber and a second separation element which is substantially liquid-impervious and gas-pervious, a floating member comprising a first separation element which is liquid-permeable and a second separation element which is substantially liquid-impervious and gas-pervious, a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and a second position wherein the liquid does interact with the at least one first substance, a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the catalytic member and a second position wherein the liquid does interact with the catalytic member, a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and the catalytic member and a second position wherein the liquid does interact with the at least one first substance and the catalytic member, a shutter that is movable at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member, and a member that moves at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member.

[0029] According to another aspect of the invention, a system comprises the self- regulating hydrogen generation device of any of the types described above and a hydrogen consuming device.

[0030] The hydrogen consuming device may comprise an element which is capable of activating a valve system which is comprised in the third chamber of the hydrogen generation device to allow hydrogen gas in the third chamber to pass into the hydrogen consuming device. The hydrogen generation device may be capable of being sealingly connected to the hydrogen consuming device in a way such that hydrogen gas in the third chamber of the hydrogen generation device is able to pass into the hydrogen consuming device. The hydrogen generation device and the hydrogen consuming device may be connected by a system which comprises a quick-butt joint. The hydrogen consuming device may be an integral part of the hydrogen generation device. The hydrogen consuming device may comprise a fuel cell. The fuel cell may be adapted for charging a portable electronic device. The fuel cell may be adapted to provide from about 1 watts to about 50 watts.

[0031] According to another aspect of the invention, a system comprises a hydrogen- based fuel cell which is adapted for being sealingly connected to the device of any of the types described above and for receiving hydrogen gas therefrom.

[0032] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and at least one of using the hydrogen gas thus formed for substantially preventing fresh liquid material from contacting the catalytic material when a predetermined threshold gas pressure is reached, allowing the liquid to pass through a first separation element which is liquid-permeable from the first chamber into a second chamber and allowing hydrogen gas to pass through a second separation element which is substantially liquid-impervious and gas-pervious, allowing a floating member comprising a first separation element which is liquid- permeable and a second separation element which is substantially liquid-impervious and gas- pervious to move relative to a liquid level inside the device, moving a flexible container containing the liquid at least from a first position wherein the liquid does not interact with the at least one first substance and a second position wherein the liquid does interact with the at least one first substance, moving a flexible container containing the liquid at least from a first position wherein the liquid does not interact with the catalytic member and a second position wherein the liquid does interact with the catalytic member, moving a flexible container containing the liquid at least from a first position wherein the liquid does not interact with the at least one first substance and the catalytic member and a second position wherein the liquid does interact with the at least one first substance and the catalytic member, moving a shutter at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member, and moving a member at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member. [0033] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and using the hydrogen gas thus formed for substantially preventing fresh liquid material from contacting the catalytic material when a predetermined threshold gas pressure is reached.

[0034] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and allowing the liquid to pass through a first separation element which is liquid-permeable from the first chamber into a second chamber and allowing hydrogen gas to pass through a second separation element which is substantially liquid-impervious and gas- pervious.

[0035] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and allowing a floating member comprising a first separation element which is liquid-permeable and a second separation element which is substantially liquid- impervious and gas-pervious to move relative to a liquid level inside the device. [0036] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and moving a flexible container containing the liquid at least from a first position wherein the liquid does not interact with the at least one first substance and a second position wherein the liquid does interact with the at least one first substance. [0037] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and moving a flexible container containing the liquid at least from a first position wherein the liquid does not interact with the catalytic member and a second position wherein the liquid does interact with the catalytic member.

[0038] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and moving a flexible container containing the liquid at least from a first position wherein the liquid does not interact with the at least one first substance and the catalytic member and a second position wherein the liquid does interact with the at least one first substance and the catalytic member.

[0039] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and moving a shutter at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member.

[0040] According to another aspect of the invention, a method of generating hydrogen gas in a self-regulating manner is provided, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and moving a member at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member.

[0041] Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of exemplary embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:

Fig. 1 shows a side cross-section view of a first embodiment of a combination of a hydrogen generation device of the present invention (hereafter sometimes referred to as "hydrogen generator module") and a fuel cell (hereafter sometimes referred to as "electrodes module"). The combination is shown in a state in which the hydrogen generator module and the electrodes module have been fully connected together;

Fig. 2 shows a side cross-section view of the hydrogen generator module used in the embodiment shown in Fig. 1. The hydrogen generator module is shown in a state before the hydrogen generator module is connected to the electrodes module;

Fig. 3 shows a front view of the hydrogen generator module shown in Fig. 2; Fig. 4 shows a side cross-section view of the electrodes module used in the embodiment shown in Fig. 1. The electrodes module is shown in a state before the hydrogen generator module is connected to the electrodes module;

Fig. 5 shows a front view of the electrodes module shown in Fig. 4;

Fig. 6 shows an enlarged side cross-section view of a portion of the electrodes module and the hydrogen generator module in a state prior to the hydrogen generator module being fully connected to the electrodes module. The arrow indicates movement of the electrodes module towards the hydrogen generator module and deflection of the locking members which will cause a locking together of the electrodes module and the hydrogen generator module;

Fig. 7 shows an enlarged side cross-section view of a portion of the electrodes module and the hydrogen generator module in a state of hydrogen generation and transfer of the hydrogen from the hydrogen generator module to the electrodes module. The arrows indicate hydrogen gas flows and liquid fuel flows;

Fig. 8 shows an enlarged side cross-section view of a portion of the electrodes module and an electrical load connected thereto;

Fig. 9 shows an enlarged side cross-section view of a portion of the electrodes module and the hydrogen generator module in a connected state according to another embodiment of the invention. This embodiment is similar to that of Fig. 1 and also includes a secondary sealing system utilizing two O-rings;

Fig. 10 shows an enlarged side cross-section view of a portion of the electrodes module and the hydrogen generator module in a connected state according to another embodiment of the invention. This embodiment is similar to that of Fig. 1 and also includes a secondary sealing system utilizing an annular sealing member;

Fig. 1 1 shows a side cross-section view of a second embodiment of a hydrogen generator module in a state where the module is fully connected to an electrodes module. This embodiment is similar to that of Fig. 1 and also includes two separate breakable containers for the liquid fuel constituents and a perforated support member;

Fig. 12 shows a side cross-section view of a third embodiment of a hydrogen generator module in a state where the module is fully connected to an electrodes module. This embodiment is similar to that of Fig. 1 and also includes a single breakable container for the fuel constituents and a perforated support member;

Fig. 13 shows a side cross-section view of a fourth embodiment of a hydrogen generator;

Fig. 14 shows a side cross-section view of the container used on the embodiment shown in Fig. 13; Fig. 15 shows a side cross-section view of the container cover and the floating assembly used on the embodiment shown in Fig. 13;

Fig. 16 shows a side cross-section view of the housing portion of the floating assembly used on the embodiment shown in Fig. 13;

Fig. 17 shows a side cross-section view of the liquid fuel blocking membrane member used on the embodiment shown in Fig. 13;

Fig. 18 shows a side cross-section view of the catalytic member used on the embodiment shown in Fig. 13;

Fig. 19 shows a side cross-section view of the gas blocking membrane member used on the embodiment shown in Fig. 13;

Fig. 20 shows a side cross-section view of a fifth embodiment of a hydrogen generator in one mode of operation;

Fig. 21 shows a side cross-section view of the embodiment shown in Fig. 20 in another mode of operation;

Fig. 22 shows a side cross-section view of the container cover and valve used on the embodiment shown in Fig. 20;

Fig. 23 shows a side cross-section view of the container used on the embodiment shown in Fig. 20;

Fig. 24 shows a side cross-section view of an assembly used on the embodiment shown in Fig. 20 which includes a support screen, solid fuel chamber and catalytic element;

Fig. 25 shows a side view of a chamber cap member used on the embodiment shown in Fig. 20;

Fig. 26 shows a side cross-section view of the support screen used on the embodiment shown in Fig. 20;

Fig. 27 shows a partial cross-section view of the solid fuel chamber used on the embodiment shown in Fig. 20;

Fig. 28 shows a cross-section view of the catalytic element used on the embodiment shown in Fig. 20;

Fig. 29 shows a cross-section view of the flexible dilutant chamber used on the embodiment shown in Fig. 20;

Fig. 30 shows a cross-section view of the base support member used on the embodiment shown in Fig. 20;

Fig. 31 shows a side view of the compression spring used on the embodiment shown in Fig. 20; Fig. 32 shows a side cross-section view of a sixth embodiment of a hydrogen generator in a non-working mode of operation;

Fig. 33 shows a side cross-section view of the embodiment shown in Fig. 32 in a working mode of operation;

Fig. 34 shows a side cross-section view of the container used on the embodiment shown in Fig. 32;

Fig. 35 shows a side cross-section view of the container cover system used on the embodiment shown in Fig. 32;

Fig. 36 shows a side cross-section view of the container cover system shown in Fig. 35 after it has been placed into a working mode;

Fig. 37 shows a side cross-section view of the retaining ring member used on the embodiment shown in Fig. 32;

Fig. 38 shows a side cross-section view of the biasing member used on the embodiment shown in Fig. 32;

Fig. 39 shows a side cross-section view of the container cover used on the embodiment shown in Fig. 32;

Fig. 40 shows a side cross-section view of the catalytic element used on the embodiment shown in Fig. 32;

Fig. 41 shows a side cross-section view of the connecting pin member used on the embodiment shown in Fig. 32;

Fig. 42 shows a side cross-section view of the deformable sealing member used on the embodiment shown in Fig. 32;

Fig. 43 shows a side cross-section view of the support plate member used on the embodiment shown in Fig. 32;

Fig. 44 shows a side cross-section view of a seventh embodiment of a hydrogen generator in a working mode of operation;

Fig. 45 schematically shows a vehicle having an electric motor drive system, a fuel cell system, and a battery system in one mode of operation;

Fig. 46 shows the vehicle of Fig. 45 in another mode of operation;

Fig. 47 shows the vehicle of Fig. 45 in still another mode of operation;

Fig. 48 shows the vehicle of Fig. 45 in still another mode of operation;

Fig. 49 schematically shows a vehicle having an electric motor/generator drive system, a fuel cell system, and a battery system in one mode of operation; and

Fig. 50 schematically shows a system for generating electrical energy and for recycling/reusing spent components thereof in the system. DETAILED DECRIPTION OF THE INVENTION

[0043] The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice. In the following the materials contained in the first (liquid fuel) chamber of the hydrogen generator module (e.g., at least one first substance and a liquid) will collectively be referred to as "liquid fuel".

[0044] As is shown in Figs. 1-5, the combination FC includes a hydrogen generator module or cartridge 1 and an electrodes module 2. The cartridge 1 includes a liquid fuel chamber 3 for storing a specified amount of liquid fuel, one or more valves/vents 4, a hydrogen generation chamber 5, a catalytic element 6 arranged in the hydrogen generation chamber 5, a gas blocking element 9 functioning as first separator element, a hydrogen collector chamber 8, a liquid fuel blocking element 7 functioning as second separator element, an (e.g., annular) water absorption element 10, and a valve 11 for allowing hydrogen to pass into the electrodes module 2.

[0045] By way of non-limiting example, the liquid fuel chamber 3 may have a volume of from about 5 cm³ to about 2000 cm³, preferably e.g., from about 20 cm³ to about 100 cm³. The hydrogen generation chamber 5 may have a volume of from about 0.1 cm³ to about 50 cm³, preferably e.g., from about 0.5 cm³ to about 5 cm³. The hydrogen collector chamber 8 may have a volume of from about 0.2 cm³ to about 100 cm³, preferably e.g., from about 1 cm³ to about 10 cm³.

[0046] The gas blocking element 9 separates the liquid fuel chamber 3 and the hydrogen generation chamber 5. The operating portion of the gas blocking element 9 is a membrane. This membrane is preferably a hydrophilic membrane. By way of non-limiting example, the membrane may occupy just a portion of the gas blocking element 9, e.g., from about 20 % to 100 % of the gas blocking element 9. The gas blocking element 9 functions by taking advantage of a capillary effect of the porous hydrophilic membrane. Liquid fuel in the porous membrane substantially prevents hydrogen crossover from the hydrogen generator chamber 5 to the liquid fuel chamber 3. At the same time, gas pressure substantially prevents liquid fuel penetration from the liquid fuel chamber 3 into the hydrogen generation chamber 5 in a non-operating condition of the electrodes module 2. A metal or non-metal hydrophilic mesh also may be used as the gas blocking membrane portion of element 9. By way of non-limiting example, the gas blocking membrane of element 9 can have a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm.

[0047] The hydrophilic porous membrane of the gas blocking element 9 can be made of any material that is stable in the liquid fuel medium. Non-limiting suitable examples of such a material include hydrophilic polymers such polysulfones, polyurethanes, modified PE, modified PP and others. The hydrophilic porous membrane can also have the form of a metallic hydrophilic mesh, e.g., made of stainless steel, and can also be made from hydrophilic ceramic materials and/or hydrophilic cloth materials.

[0048] The one or more valves/vents 4 can include or have the form of a pressure compensating membrane for the prevention of pressure pulsation which occurs during hydrogen generation. This membrane can be incorporated within the liquid fuel chamber 3. This membrane can be a hydrophobic membrane. Any hydrophobic porous material which is stable in the liquid fuel medium can be used as the membrane material, however, including one or more hydrophobic polymers such as, e.g., PTFE, PP, PE, polyamides (nylons) and others produced by Gore, Pall, General Electric, Millipore and other companies. The material can also comprise one or more hydrophobic ceramic materials and/or hydrophobic cloth materials. [0049] When the liquid fuel comprises a borohydride compound and water, the hydrogen generation chamber 5 functions as follows: hydrogen is produced by the following reaction: BH^ + 2H₂O = BO ₂ + 4H₂. The generated hydrogen is ultimately used to operate the electrodes module through the oxidation (consumption) of the hydrogen at the anode with concurrent production of electrical energy usable by a load L (see Fig. 8). Hydrogen is supplied to the electrodes module 2 according to the consumption thereof. In other words, when there is no consumption of hydrogen in the electrodes module 2 the pressure generated by the already produced hydrogen gas will prevent fresh liquid fuel from the liquid fuel chamber 3 to enter the hydrogen generation chamber 5, thereby stopping the production of hydrogen. Once the electrodes module operates again and consumes hydrogen, the hydrogen pressure will be reduced until fresh liquid fuel can enter the hydrogen generation chamber 3 again, resulting in the generation of further hydrogen which will be consumed by module 2, etc. [0050] Of course, the present invention is not limited to the use of borohydride compounds as the source of hydrogen gas for the self-regulating hydrogen generation device of the present invention. Non-limiting examples of substances which may be used instead of or in combination with one or more borohydride compounds include metal hydrides and alumohydrides such as, e.g., compounds of formulae MeH (Me = alkali metal, in particular Li, Na and K), Me⁵H₂ (Me' = Zn or an alkaline earth metal such as, e.g., Be, Mg, Ca, Sr and Ba) and MeAIH₄ (Me = alkali metal, in particular Li, Na and K). Generally speaking, any substance or compound which is at least somewhat soluble in the liquid which is present in the at least first chamber, is stable per se under ambient (and, if needed, substantially moisture-free) conditions and can be decomposed (e.g., catalytically and/or thermally) to form hydrogen gas is suitable as a hydrogen source for use in the present invention. A solid fuel may preferably be utilized in each of the herein disclosed embodiments such as of the type disclosed in related US application Nos. 61/055,677 filed on May 23, 2008 (Attorney Docket No. V34383) and 12/333,747 filed on December 12, 2008 (Attorney Docket No. P35532), the entire disclosure of which are hereby expressly incorporated by reference.

[0051] The catalytic element 6 arranged within the chamber 5 may, for example, comprise one or more of the following as the catalytically active material: Pt, Pd, Ru, Rh, Ir, Au, Co, Fe, Ni (preferably as zero valency metals and/or oxides). The catalytically active material is preferably carried by a high surface area support, thereby forming the element 6. The catalytic element 6 may occupy only a portion of the hydrogen generation chamber 5. By way of non- limiting example, the catalytic element 6 may occupy from about 10 % to about 90 % of the volume of the chamber 5. The element 6 is preferably positioned in a central area of the chamber 5. By way of non-limiting example, with the exemplary dimensions of the chambers of the hydrogen generator module 1 set forth above, the distance between the catalytic element 6 and the gas blocking element 7 may be from about 0.1 mm to about 5 mm.

[0052] Examples of suitable materials for supporting the catalytically active material of the element 6 include different types of ceramic and carbon materials with a high surface area. The catalytic element 6 may be present in various forms and shapes including, e.g., a sheet, a plate, a cylindrical structure, a honeycomb structure, granules, etc.

[0053] The liquid fuel blocking element 7 will usually be arranged on a side of the chamber 5 which is opposite the gas blocking element 9. Element 7 will usually comprise a porous membrane, preferably a hydrophobic membrane. The liquid fuel blocking membrane 7 will usually perform hydrogen and fuel separation in the hydrogen generator module 1 as well as prevent leakage of liquid fuel out of the hydrogen generator chamber 5, act to clean and dry the gas passing through element 7, and allow hydrogen H pass into the gas collector chamber 8 (see Fig. 7). By way of non-limiting example, the liquid fuel blocking membrane of element 7 may have a thickness of from about 20 μm and about 300 μm, a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm, and provide a gas permeability pressure from about 20 mbar to about 100 mbar. Also, the gas permeability pressure of the membrane of element 7 should not be higher than the gas permeability pressure of the membrane of element 9. By way of non-limiting example, the distance between catalytic element 6 and the liquid fuel blocking element 7 may be from about 0.1 mm to about 5 mm (with the exemplary dimensions of the various chambers of the module 1 set forth above).

[0054] The membrane of the liquid fuel blocking element 7 can be made of any hydrophobic porous material which is stable in the medium present in chamber 5 and which can be used as a membrane material. For example, the membrane can be made of one or more hydrophobic polymers such as PTFE, PP, PE, polyamides (nylons) and other materials produced by Gore, Pall, General Electric, Millipore and other companies. It can also be made of one or more hydrophobic ceramic materials and/or hydrophobicc cloth materials. [0055] The water absorption element 10 can comprise any porous hydrophilic matrix/support material such as, e.g., a polyurethane. It can also comprise a hydrophilic foam, cloth, and/or paper material. The matrix/support material may incorporate absorption components such as, e.g., Carbopols, polyacrylic acid, Quick-Solid paper and other materials. The element 10 may, for example, have a toroidal configuration with the following exemplary and non-limiting dimensions: an internal peripheral length of up to about 20 cm, and preferably from about 3 to about 10 cm; an external peripheral length of from about 1 cm to about 30 cm, and preferably from about 4 cm to about 15 cm; a cross-sectional thickness (tore) of from about 0.1 mm to about 30 mm, preferably from about 0.5 mm to about 10 mm. [0056] The valve 11 may be biased towards a closed position by, e.g., a spring, and is moved to the open position upon engagement with a pin 17 which is arranged within the electrodes module 2 when the hydrogen generator module 1 and the electrodes module 2 are connected together via locking members 12. As is shown in Fig. 7, once the valve 11 is open, the hydrogen gas H is allowed to flow out of the chamber 8 of the hydrogen generator module 1 and into the electrodes module 2 via the opening OP.

[0057] The electrodes module 2 includes an anode 14, a cathode 13, an electrolyte chamber 15, a pin 17 for opening the valve 11, a system of deflectable locking members 12, one or more safety valves 16, and an air opening AO which allows outside air A to enter into the electrodes module 2 (thereby providing oxygen for reduction at the cathode 13). [0058] The safety valve 16 can be configured to open at pressures of from about 1 bar to about 1000 bar, and preferably opens at pressures from about 10 bar to about 50 bar. The valve 16 can also be replaced with a membrane of the type used in element 4 as discussed above. [0059] Any type of hydrogen fuel cells may be used in combination with the hydrogen generator system of the present invention. For example, alkaline, acidic or PEM electrolytes may be used in the electrodes module 2. The electrolyte used in chamber 15 may be in the liquid state as well as solid, gel or matrix states. [0060] The liquid fuel for the hydrogen generator module 1 may, for example, comprise borohydride based alkaline solutions. Furthermore, suspensions may be used as the liquid fuel as well. In this regard, reference is made to, e.g., U.S. Patent Nos. 6,554,877, 6,562,497, 6,758,871 and 6,773,470 as well as to U.S. Patent Application Nos. 2005/0155279 and 2006/02131 19, the entire disclosures whereof are incorporated by reference herein. All of these documents describe borohydride-based liquid fuel systems for liquid fuel cells which can be used as liquid fuel for the hydrogen generation device of the present invention. Of course the liquid fuel for use in the present invention is not limited to borohydride based fuels. Rather, any substance which can be used in a catalytic reaction which results in the formation of gaseous hydrogen is suitable for the purposes of the present invention.

[0061] As stated above, the liquid fuel can be stored in the fuel chamber 3 as single- component (e.g., borohydride-based) solution or suspension or as binary product composed of a fuel concentrate and a dilutant. Binary fuel usage may provide higher fuel stability, making it possible to store the liquid fuel in the module 1 on a long term basis (before usage). [0062] Solid borohydride based compositions (e.g., in the form of powders, granules, flakes or tablets) as well as liquid or semi-solid borohydride compositions (e.g., in the form of solutions, suspensions or pastes) represent non-limiting examples of materials which can be used as fuel concentrates. In this regard, the fuel concentrate and a dilutant can be placed in chamber 3 separately and/or in separate containers as is shown in the embodiment of Fig. 1 1. The concentrate and dilutant can be mixed just before the electrodes module 2 is to be utilized. [0063] Fig. 6 illustrates how the locking members 12 deflect outwards as the modules 1 and 2 are moved into connection with each other. Once the modules 1 and 2 are fully connected, the projecting portions or locking projections LP of the members 12 snap into recesses LR formed in the module 1 (compare Figs. 1 and 6).

[0064] Fig. 9 shows one non-limiting way of providing additional sealing between the hydrogen generator module 1 and the electrodes module 2 when these modules are connected together. In this embodiment, two O-ring seals OS are used to provide sealing between these modules.

[0065] Fig. 10 shows another non-limiting way of providing additional sealing between the hydrogen generator module 1 and the electrodes module 2 when these modules are connected together. In this embodiment, a single sealing ring SR is used to provide sealing between these modules.

[0066] Fig. 1 1 shows another embodiment of a combination or system according to the present invention. This combination includes a hydrogen generator module or cartridge 10 and an electrodes module 2. The cartridge 10 is similar to that of Fig. 1 except that the liquid fuel chamber 30 for storing a liquid fuel houses two separate storage containers 30a and 30b. Each container 30a and 30b can have the form of a breakable and/or burstable flexible material bag which can be broken open when the user moves a rear wall of the module 10 towards a support 180. This movement is facilitated by one or more flexible sections or accordion folds 190 formed in the wall of the module 10. Thus, when a user moves the rear wall of module 10 towards the support 180, the bags 30a and 30b experience compression. When enough compressive pressure is applied to the bags 30a and 30b, they break open and spill their contents into the chamber 30. Furthermore, because the support 180 is perforated with openings, the fuel from the chamber 30 will be allowed to flow into the chamber 50 after passing through element 90. The combination will then function in the same way as the embodiment of Fig. 1. A fuel concentrate can be contained in container 30a and a dilutant can be placed in container 30b. The concentrate and dilutant can be mixed just before the electrodes module 2 is to be utilized. The hydrogen generator module 10 also includes one or more valves/vents 40, and a hydrogen generation chamber 50, a catalytic element 60 arranged in the hydrogen generation chamber 50, a liquid fuel blocking element 70, a hydrogen collecting chamber 80, a gas blocking element 90, an annular water absorption element 110, and a valve 111 for allowing hydrogen to pass into the electrodes module 2.

[0067] The bags 30a and 30b can be made of a puncturable and/or breakable and/or burstable material produced from typical contractual polymeric materials which are stable in the liquid fuel medium. These include, e.g., PP, PE, PVC and other materials. [0068] The support element 180 can be made from any material which is stable in the liquid fuel medium. For example, it can be made of PE, PP, ABS, SS 316 and similar materials. [0069] Fig. 12 shows another embodiment of the hydrogen generator/fuel cell combination or system of the present invention. This combination includes a hydrogen generator module or cartridge 10' and an electrodes module 2. The cartridge 10' is similar to that of Fig. 1 1 except that the liquid fuel chamber 30 houses a single large breakable container 300 which contains the liquid fuel. The container 300 can have the form of a breakable flexible material bag which can be broken open when the user moves a rear wall of the module 10' towards the support 180. This movement is facilitated by one or more flexible sections or accordion folds 190 formed in the wall of the module 10'. Thus, when a user moves the rear wall of module 10' towards the support 180, the bag 300 experiences compression. When enough compressive pressure is applied to the bag 300, it breaks open and spills its contents into the chamber 30. Furthermore, because the support 180 is perforated with openings, the fuel from the chamber 30 will be allowed to flow into the chamber 50 after passing through element 90. The combination will then function is the same way as the embodiment of Fig. 1. [0070] Figs. 13-19 show another embodiment of the hydrogen generator/fuel cell combination or system of the present invention. This combination includes a hydrogen generator module 400 that is coupled to a fuel cell or electrodes module 402 via one of more hydrogen supply conduits HS. One or more valves 411 can be utilized to regulate the flow of hydrogen from the module 400 to the fuel cell 402. The hydrogen generator 400 utilizes a liquid dilutant chamber 403 which is arranged within a housing 401a and a housing cover 401b. The housing cover 401b is preferably sealed to the housing 401a in order to form a sealed container. This sealing can be by way of e.g., ultrasonic welding the cover 401b to the housing 401a after the hydrogen generator assumes the configuration shown in Fig. 13. A solid fuel SF is arranged within the housing 401a/401b. By way of non-limiting example, the solid fuel SF can be arranged within a defined space that can be accessed by the dilutant D. The solid fuel SF can also be arranged with a cartridge (not shown) which can be insertable into the defined space of the housing. In the embodiment shown in Fig. 13, the solid fuel SF is housed in the defined space such that dilutant D can pass into the defined space via openings or passages formed in the wall separating the defined space from the dilutant chamber 403 and thereby interact with the solid fuel SF. As will be explained later on, the composition formed by the interacting of the solid fuel SF and the dilutant D will form hydrogen gas when the composition interacts with a catalyst or catalytic member 406.

[0071] The hydrogen generator 400 also includes one or more valves/vents 404. The valve 404 is designed to vent hydrogen gas when the pressure in the chamber 403 exceeds a predetermined amount. The one or more valves/vents 404 can include or have the form of a pressure compensating membrane for the prevention of pressure pulsation which occurs during hydrogen generation. This membrane can be incorporated within the liquid fuel chamber 403. This membrane can be a hydrophobic membrane. Any hydrophobic porous material which is stable in the liquid fuel medium can be used as the membrane material, however, including one or more hydrophobic polymers such as, e.g., PTFE, PP, PE, polyamides (nylons) and others produced by Gore, Pall, General Electric, Millipore and other companies. The material can also comprise one or more hydrophobic ceramic materials and/or hydrophobic cloth materials. [0072] The hydrogen generator 400 also includes a flexible coil-shaped conduit which conveys the hydrogen gas from a floating member FM to a wall of the container cover 401b. As is apparent from Fig. 13, the vertical position of the floating member FM will vary based on the dilutant level DL (see Fig. 14), e.g., as the dilutant/fuel composition level DL drops, the floating member FM also drops under the influence of gravity. The floating member FM includes a first separator element or gas blocking element 409, a hydrogen generation chamber 405, a catalytic element 406 arranged in the hydrogen generation chamber 405, a hydrogen collector chamber

408, and a second separator element or liquid fuel blocking element 407.

[0073] By way of non-limiting example, the liquid fuel chamber 403 may have a volume of from about 5 cm³ to about 2000 cm³, preferably e.g., from about 20 cm³ to about 100 cm³. The hydrogen generation chamber 405 may have a volume of from about 0.1 cm³ to about 50 cm³, preferably e.g., from about 0.5 cm³ to about 5 cm³. The hydrogen collector chamber 408 may have a volume of from about 0.2 cm³ to about 100 cm³, preferably e.g., from about 1 cm³ to about 10 cm³.

[0074] The gas blocking element 409 separates the liquid fuel chamber 403 and the hydrogen generation chamber 405. That is, it prevents hydrogen gas from passing from the chamber 405 into the chamber 403, while allowing fuel to pass through the element 409 from the chamber 403 to the chamber 405. The operating portion of the gas blocking element 409 is a membrane. This membrane is preferably a hydrophilic membrane. By way of non-limiting example, the membrane may occupy just a portion of the gas blocking element 409, e.g., from about 20 % to 100 % of the gas blocking element 409. The gas blocking element 409 functions by taking advantage of a capillary effect of the porous hydrophilic membrane. Liquid fuel in the porous membrane substantially prevents hydrogen crossover from the hydrogen generator chamber 405 to the liquid fuel chamber 403. At the same time, gas pressure substantially prevents liquid fuel penetration from the liquid fuel chamber 403 into the hydrogen generation chamber 405 in a non-operating condition of the fuel cell 402. A metal or non-metal hydrophilic mesh also may be used as the gas blocking membrane portion of element 409. The hydrophilic porous membrane of the gas blocking element 409 can be made of any material that is stable in the liquid fuel medium. Non-limiting suitable examples of such a material include hydrophilic polymers such polysulfones, polyurethanes, modified PE, modified PP and others. The hydrophilic porous membrane can also have the form of a metallic hydrophilic mesh, e.g., made of stainless steel, and can also be made from hydrophilic ceramic materials and/or hydrophilic cloth materials. By way of non-limiting example, the gas blocking membrane of element 409 can have a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm.

[0075] When the liquid fuel comprises a borohydride compound and water, the hydrogen generation chamber 405 functions as follows: hydrogen is produced by the following reaction: BH ₄ + 2H₂O = BO ₂ + 4H₂. The generated hydrogen is ultimately used to operate the electrodes module 402 (after passing thought the conduit FT and hydrogen supply HS) through the oxidation (consumption) of the hydrogen at the anode with concurrent production of electrical energy usable by a load. Hydrogen is supplied to the electrodes module 402 according to the consumption thereof. In other words, when there is no consumption of hydrogen in the electrodes module 402, the pressure generated by the already produced hydrogen gas will prevent fresh liquid fuel from the liquid fuel chamber 403 to enter the hydrogen generation chamber 405, thereby stopping the production of hydrogen. Once the electrodes module 402 operates again and consumes hydrogen, the hydrogen pressure will be reduced until fresh liquid fuel can enter the hydrogen generation chamber 405 again, resulting in the generation of further hydrogen which will be consumed by module 402, etc.

[0076] Of course, as in the previous embodiments, the embodiment shown in Fig. 13 is not limited to the use of borohydride compounds as the source of hydrogen gas for the self- regulating hydrogen generation device of the present invention. Non-limiting examples of substances which may be used instead of or in combination with one or more borohydride compounds include metal hydrides and alumohydrides such as, e.g., compounds of formulae MeH (Me = alkali metal, in particular Li, Na and K), Me'H₂ (Me' = Zn or an alkaline earth metal such as, e.g., Be, Mg, Ca, Sr and Ba) and MeAlH₄ (Me = alkali metal, in particular Li, Na and K). Generally speaking, any substance or compound which is at least somewhat soluble in the liquid which is present in the at least first chamber, is stable per se under ambient (and, if needed, substantially moisture-free) conditions and can be decomposed (e.g., catalytically and/or thermally) to form hydrogen gas is suitable as a hydrogen source for use in the present invention. [0077] The catalytic element 406 arranged within the chamber 405 may, for example, comprise one or more of the following as the catalytically active material; Pt, Pd, Ru, Rh, Ir, Au, Co, Fe, Ni (preferably as zero valency metals and/or oxides). The catalytically active material is preferably carried by a high surface area support, thereby forming the element 406. The catalytic element 406 may occupy only a portion of the hydrogen generation chamber 405. By way of non-limiting example, the catalytic element 406 may occupy from about 10 % to about 90 % of the volume of the chamber 405. The element 406 is preferably positioned in a central area of the chamber 405. By way of non-limiting example, with the exemplary dimensions of the chambers of the hydrogen generator module 400 set forth above, the distance between the catalytic element 406 and the gas blocking element 407 may be from about 0.1 mm to about 5 mm. [0078] Examples of suitable materials for supporting the catalytically active material of the element 406 include different types of ceramic and carbon materials with a high surface area. The catalytic element 406 may be present in various forms and shapes including, e.g., a sheet, a plate, a cylindrical structure, a honeycomb structure, granules, etc.

[0079] The liquid fuel blocking element 407 will usually be arranged on a side of the chamber 405 which is opposite the gas blocking element 409. Element 407 will usually comprise a porous membrane, preferably a hydrophobic membrane. The liquid fuel blocking membrane 407 will usually perform hydrogen and fuel separation in the hydrogen generator module 400, prevent leakage of liquid fuel out of the hydrogen generator chamber 405 and into the hydrogen collection chamber 408, act to clean and dry the hydrogen gas passing through element 407 and into the chamber 408, and allow hydrogen pass into the gas collector chamber 408. By way of non-limiting example, the liquid fuel blocking membrane of element 407 may have a thickness of from about 20 μm and about 300 μm, a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm, and provide a gas permeability pressure from about 20 mbar to about 100 mbar. Also, the gas permeability pressure of the membrane of element 407 should not be higher than the gas permeability pressure of the membrane of element 409. By way of non-limiting example, the distance between catalytic element 406 and the liquid fuel blocking element 407 may be from about 0.1 mm to about 5 mm (with the exemplary dimensions of the various chambers of the module 400 set forth above).

[0080] The membrane of the liquid fuel blocking element 407 can be made of any hydrophobic porous material which is stable in the medium, i.e., fuel and dilutant composition, present in chamber 405 and which can be used as a membrane material. For example, the membrane can be made of one or more hydrophobic polymers such as PTFE, PP, PE, polyamides (nylons) and other materials produced by Gore, Pall, General Electric, Millipore and other companies. It can also be made of one or more hydrophobic ceramic materials and/or hydrophobicc cloth materials.

[0081] The hydrogen generator shown in Figs. 13-19 utilizes a gas blocking effect. A hydrogen generation floating capsule FM includes a catalytical element 406, an upper hydrophobic membrane 407 which allows for the output of hydrogen and a lower hydrophilic membrane 409 which regulates fuel diffusion. A main advantage of this type of hydrogen generator system is that it can function in substantially the same way (and/or independent of) a fuel level. As then fuel level DL changes (e.g., due to a reduction in volume of the fuel composition occurring as a result of hydrogen production), the member FM moves accordingly (because of the flexibility of the flexible tubing FT) to thereby ensure that hydrogen generation continues even as the fuel level changes. Thus, hydrogen can be produced as long as the floating member FM is dipped into the fuel composition and as long as the fuel composition comes into contact with the catalytic element 406.

[0082] Figs. 20-31 show another embodiment of the hydrogen generator/fuel cell combination or system of the present invention. This combination includes a hydrogen generator module 500 that is coupled to a fuel cell or electrodes module 502 via one of more hydrogen supply conduits HS. One or more valves 511 can be utilized to regulate the flow of hydrogen from the module 500 to the fuel cell 502. The hydrogen generator 500 utilizes a liquid dilutant chamber 503 which is arranged within a housing 501a and a housing cover 501b. The housing cover 501b is preferably sealed to the housing 501a in order to form a sealed container. This sealing can be by way of e.g., ultrasonic welding the cover 501b to the housing 501a after the hydrogen generator assumes the configuration shown in Fig. 20. A solid fuel SF is arranged within the housing 501a/501b. By way of non-limiting example, the solid fuel SF can be arranged within a defined space that can be accessed by the dilutant D. The solid fuel SF can also be arranged with a cartridge (not shown) which can be insertable into the defined space of the housing. In the embodiment shown in Fig. 20, the solid fuel SF is housed in a solid fuel chamber SFC such that dilutant D can pass into the defined space via openings or passages formed in the wall separating the chamber SFC and thereby interact with the solid fuel SF. The chamber SFC can have an open upper end that is fixed to the support screen SS, that can receive the solid fuel SF, and which is capped by a chamber cap member CCM. By way of non-limiting example, the chamber SFC has the form of a cylindrically shaped perforated basket. As will be explained later on, the composition formed by the interacting of the solid fuel SF and the dilutant D will form hydrogen gas when the composition interacts with a catalyst or catalytic member 506.

[0083] The hydrogen generator 500 also includes one or more valves/vents 504. The valve 504 is designed to vent hydrogen gas when the pressure in the chamber 503 exceeds a predetermined amount. The one or more valves/vents 504 can include or have the form of a pressure compensating membrane for the prevention of pressure pulsation which occurs during hydrogen generation. This membrane can be incorporated within the liquid fuel chamber 503. This membrane can be a hydrophobic membrane. Any hydrophobic porous material which is stable in the liquid fuel medium can be used as the membrane material, however, including one or more hydrophobic polymers such as, e.g., PTFE, PP, PE, polyamides (nylons) and others produced by Gore, Pall, General Electric, Millipore and other companies. The material can also comprise one or more hydrophobic ceramic materials and/or hydrophobic cloth materials. [0084] The hydrogen generator 500 also includes a flexible accordion-shaped chamber which has an upper open end or lip that is fixed (via e.g., ultrasonic welding) to an inside of the housing 501a and a closed bottom end wall that contacts a support member BSM. A compression spring CS is arranged between a bottom wall of the housing 501a and the support member BSM. The spring CS expands axially to the position shown in Fig. 21 when the pressure in the chamber 503 is zero or below a predetermined pressure. On the other hand, the spring CS assumes the compressed position shown in Fig. 20 when the pressure in the chamber 503 exceeds the biasing force of the spring CS. As is apparent from Figs. 20 and 21, the vertical position of the dilυtant level DL will vary based on the pressure of the hydrogen gas in the chamber 503. In the position shown in Fig. 20, hydrogen gas production stops because the dilutant D does not come into contact with the solid fuel SF and the catalytic element 506. However, in the position shown in Fig. 21, hydrogen gas production resumes because the dilutant D comes into contact with the solid fuel SF and the catalytic element 506. The hydrogen gas that is produced in the chamber 503 passes through the support screen SS and into the hydrogen collection chamber 508. The hydrogen gas then passes through the hydrogen supply conduit HS to the fuel cell 502.

[0085] By way of non-limiting example, the liquid fuel chamber 503 may have a volume of from about 5 cm³ to about 2000 cm³, preferably e.g., from about 20 cm³ to about 100 cm³. The hydrogen generation chamber portion (i.e., the space between the level DL and the screen SS in the main hydrogen producing mode of the hydrogen generator 500) of the chamber 503 may have a volume of from about 0.1 cm³ to about 50 cm³, preferably e.g., from about 0.5 cm³ to about 5 cm³. The hydrogen collector chamber 508 may have a volume of from about 0.2 cm³ to about 100 cm³, preferably e.g., from about 1 cm³ to about 10 cm³.

[0086] Although not shown, the lower surface of the support screen SS may utilize, i.e., may be coated with or contain a layer of, a gas blocking membrane which can be a material of the type used for element 409 in Fig. 13. That is, it prevents hydrogen gas from passing from the chamber 508 into the chamber 503. The upper surface of the support screen SS may utilize, i.e., may be coated with or contain a layer of, a liquid fuel blocking membrane which can be a material of the type used for element 407 in Fig. 13. That is, it prevents liquid fuel from passing from the chamber 503 into the chamber 508.

[0087] When the liquid fuel comprises a borohydride compound and water, the hydrogen generation chamber 503 functions as follows: hydrogen is produced by the following reaction: BH^' ₄ + 2H₂O = BO ₂ + 4H₂. The generated hydrogen is ultimately used to operate the electrodes module 502 (after passing thought the hydrogen supply HS) through the oxidation (consumption) of the hydrogen at the anode with concurrent production of electrical energy usable by a load. Hydrogen is supplied to the electrodes module 502 according to the consumption thereof. In other words, when there is no consumption of hydrogen in the electrodes module 502, the pressure generated by the already produced hydrogen gas will force the dilutant level DL downward to the position shown in Fig. 20 and prevent the dilutant D from interacting with the solid fuel SF and the catalytic element 506, thereby stopping the production of hydrogen. Once the electrodes module 502 operates again and consumes hydrogen, the hydrogen pressure will be reduced in the chamber 508 and them in chamber 503 until the dilutant D rises towards the position shown in Fig. 21, resulting in the generation of further hydrogen which will be consumed by module 502, etc.

[0088] Of course, as in the previous embodiments, the embodiment shown in Fig. 20 is not limited to the use of borohydride compounds as the source of hydrogen gas or the self- regulating hydrogen generation device of the present invention. Non-limiting examples of substances which may be used instead of or in combination with one or more borohydride compounds include metal hydrides and alumohydrides such as, e.g., compounds of formulae MeH (Me = alkali metal, in particular Li, Na and K), Me'H₂ (Me' = Zn or an alkaline earth metal such as, e.g., Be, Mg, Ca, Sr and Ba) and MeAlH₄ (Me = alkali metal, in particular Li, Na and K). Generally speaking, any substance or compound which is at least somewhat soluble in the liquid which is present in the at least first chamber, is stable per se under ambient (and, if needed, substantially moisture-free) conditions and can be decomposed (e.g., catalytically and/or thermally) to form hydrogen gas is suitable as a hydrogen source for use in the present invention. [0089] The catalytic element 506 arranged within the chamber 503 can be, by way of non-limiting example, a generally cylindrical-shaped member having one end coupled to the support screen SS and a lower end portion which is configured to interact with the dilutant D (see Fig. 21). The catalytic element 506 may, for example, comprise one or more of the following as the catalytically active material: Pt, Pd, Ru, Rh, Ir, Au, Co, Fe, Ni (preferably as zero valency metals and/or oxides). The catalytically active material is preferably carried by a high surface area support, thereby forming the element 506. The catalytic element 506 may occupy only a portion of the hydrogen generation chamber 503. By way of non-limiting example, the catalytic element 506 may occupy from about 10 % to about 90 % of the volume of the chamber 503. The element 506 is preferably positioned in a central area of the chamber 503. [0090] Examples of suitable materials for supporting the catalytically active material of the element 506 include different types of ceramic and carbon materials with a high surface area. The catalytic element 506 may be present in various forms and shapes including, e.g., sheets, plates, a cylindrical structure of the type shown in Fig. 20, a honeycomb structure, granules, etc. [0091] The hydrogen generator shown in Fig. 20 utilizes a solid fuel SF and a dilutant D which are stored separately. During storage or stand-by mode (no hydrogen consumption by the fuel cell 502) the dilutant D and the catalytic element 506 (as well as the dilutant D and the solid fuel SF) are separated by the hydrogen gas and, as a result, hydrogen is not produced (Fig. 20). In working mode, however, the solid fuel SF and the catalytical element 506 are submerged in the dilutant D (which can be, e.g., water) by virtue of the spring SC causing the dilutant D to rise up to the point where the solid fuel SF and the catalytic element 506 are submerged (Fig. 21). Thus, the device functions with different modes depending on the hydrogen pressure, and also functions in different modes based on changes in the hydrogen gas volume resulting from the consumption of hydrogen gas by the fuel cell 502. The spring CS also functions to maintain a substantially constant inside hydrogen gas pressure in the chamber 503. As with previous embodiments, hydrogen is produced as result of fuel hydrolysis on the catalyst area (Fig 21).

Furthermore, if and when the pressure increases in the chamber 503 more than a predetermined amount (e.g., such as might occur in an emergency situation) the valve 504 opens so that the pressure is released. The valve 504 may also allow liquid fuel to flow out of the housing 501a in certain conditions.

[0092] Fig. 20 thus shows a siphon type hydrogen generator in a storage or stand-by mode with hydrogen not being consumed by the fuel cell 502. Fig. 21 shows the siphon type hydrogen generator of Fig. 20 in an operating mode with hydrogen being produced and consumed by the fuel cell 502.

[0093] Examples of suitable materials for solid fuel container SFC include metals such as, e.g., stainless steel. The container SFC may be present in various forms and shapes including, e.g., a cylindrical structure of the type shown in Fig. 20, a flexible sack, etc.

[0094] Examples of suitable materials for support screen SS include metals such as, e.g., stainless steel. The support screen SS may be present in various forms and shapes including, e.g., a porous plate, a porous sheet, etc.

[0095] Examples of suitable materials for chamber FDC include materials which are used to form the chambers 30a and 30b and 300 shown and described in the embodiments of

Figs. 1 1 and 12. The flexible chamber FDC may be present in various forms and shapes including, e.g., a cylindrical structure of the type shown in Fig. 20, a flexible sack, etc.

[0096] Examples of suitable materials for support member BSM include metals such as, e.g., stainless steel. The support member BSM may be present in various forms and shapes including, e.g., a plate, a sheet, etc.

[0097] Examples of suitable materials for compression spring CS include metals such as, e.g., stainless steel. The spring CS may be present in various forms and shapes including, e.g., a helical wire spring, a compressible/expandable material, etc.

[0098] Figs. 32-43 show another embodiment of the hydrogen generator/fuel cell combination or system of the present invention. This combination includes a hydrogen generator module 600 that can be coupled to a fuel cell or electrodes module (not shown) via one of more hydrogen supply conduits HS. One or more valves (not shown) can be utilized to regulate the flow of hydrogen from the module 600 to the fuel cell. The hydrogen generator 600 utilizes a liquid dilutant chamber 603 which is arranged within a housing 601a and a housing cover 601b.

The housing cover 601b is preferably sealed to the housing 601a in order to form a sealed container. This sealing can be by way of e.g., ultrasonic welding the cover 601b to the housing

601a after the hydrogen generator assumes the configuration shown in Fig. 32. A solid fuel SF is arranged within the housing 601a/601b. By way of non-limiting example, the solid fuel SF can be arranged within a defined space that can be accessed by the dilutant D. The solid fuel SF can also be arranged with a cartridge (not shown) which can be insertable into the defined space of the housing. In the embodiment shown in Fig. 32, the solid fuel SF is housed in a solid fuel chamber defined by a porous wall such that dilutant D can pass into the defined space via openings or passages formed in the wall separating the solid fuel SF and the chamber 603. As will be explained later on, the composition formed by the interacting of the solid fuel SF and the dilutant D will form hydrogen gas when the composition interacts with a catalyst or catalytic member 606.

[0099] The hydrogen generator 600 may also include one or more valves/vents (not shown) but similar to those used in any of the previous embodiments. The valve(s) may be designed to vent hydrogen gas when the pressure in the chamber 603 exceeds a predetermined amount. The one or more valves/vents can also include or have the form of a pressure compensating membrane for the prevention of pressure pulsation which occurs during hydrogen generation. This membrane can be incorporated within the liquid fuel chamber 603. This membrane can be a hydrophobic membrane. Any hydrophobic porous material which is stable in the liquid fuel medium can be used as the membrane material, however, including one or more hydrophobic polymers such as, e.g., PTFE, PP, PE, polyamides (nylons) and others produced by Gore, Pall, General Electric, Millipore and other companies. The material can also comprise one or more hydrophobic ceramic materials and/or hydrophobic cloth materials. [0100] The hydrogen generator 600 also includes a shutter valve system which can be moved to the open position shown in Fig. 33 from the closed position shown in Fig. 32. The shutter valve system includes a support plate member SPM, a deformable sealing member DSM, a biasing member BM, a retaining ring member RRM and a connecting pin member CPM. The support plate member SPM is connected or fixed to one end of the connecting pin member CPM. The other end of the connecting pin member CPM is connected or fixed to a center area of the biasing member BM. The deformable sealing member DSM is connected or fixed to a side of the member SPM which faces the catalytic member 606. An outer edge area of the biasing member BM is connected or fixed to the housing cover 601b via the retaining ring member RRM.

[0101] As is apparent from a comparison of Figs. 32 and 33, when a force F is applied in the direction of the arrow (Fig. 33) and is sufficient to overcome the biasing force of the biasing member BM, the pin CPM moves inwardly and causes the member SPM and the member DSM attached thereto to move away from the catalytic member 606. This allows the fuel composition to come into contact with the catalytic member 606 which in turn causes hydrogen to be produced. On the other hand, when the force F is removed (Fig. 32), the pin CPM moves outwardly under the influence of the biasing member BM and causes the member SPM and the member DSM attached thereto to move towards the catalytic member 606. This prevents the fuel composition from coming into contact with the catalytic member 606 which in turn stops hydrogen from being produced. In the position shown in Fig. 32, hydrogen gas is not produced because the fuel composition (formed by interaction of the solid fuel SF and the dilutant D) does not come into contact with the catalytic element 606. However, in the position shown in Fig. 33, hydrogen gas production starts/resumes because the fuel composition comes into contact with the catalytic element 606. The hydrogen gas that is produced in the chamber 603 passes through the hydrogen supply conduit HS to the fuel cell.

[0102] By way of non-limiting example, the liquid fuel chamber 603 may have a volume of from about 5 cm³ to about 2000 cm³, preferably e.g., from about 20 cm³ to about 100 cm³. The hydrogen generation chamber portion (i.e., the empty space between the level and the housing) of the chamber 603 may have a volume of from about 0.1 cm³ to about 50 cm³, preferably e.g., from about 0.5 cm³ to about 5 cm³.

[0103] Although not shown, a lower or upper surface of a member arranged in the hydrogen output connector HOC may utilize, i.e., may be coated with or contain a layer of, a liquid blocking membrane which can be a material of the type used for element 407 in Fig. 13. That is, it prevents the fuel composition from passing from the chamber 603 to the hydrogen supply HS while allowing hydrogen gas to pass from the chamber 603 to the hydrogen supply HS.

[0104] When the liquid fuel comprises a borohydride compound and water, the hydrogen generation chamber 603 functions as follows: hydrogen is produced by the following reaction: BH ₄ + 2H₂O = BO^' ₂ + 4H₂. The generated hydrogen is ultimately used to operate the electrodes module (after passing thought the hydrogen supply HS) through the oxidation (consumption) of the hydrogen at the anode with concurrent production of electrical energy usable by a load. Hydrogen is supplied to the electrodes module or fuel cell according to the consumption thereof. In other words, when there is no consumption of hydrogen in the electrodes module, the pressure generated by the already produced hydrogen gas can be detected with, e.g., a pressure sensor PS, which can then activate, e.g., an electrically activated mechanical device, i.e., a solenoid (not shown) that will remove the force F thereby causing the hydrogen generator 600 to assume the position shown in Fig. 32. In the position shown in Fig. 32, the fuel composition is prevented from interacting with the catalytic element 606 by the shutter system, thereby stopping the production of hydrogen. Once the electrodes module operates again and consumes hydrogen, the pressure drop can be detected by the sensor PS and the hydrogen generator 600 can be placed into the configuration shown in Fig. 32 whereby the shutter system is moved to the open position and the fuel composition comes into contact with the catalytic element 606, resulting in the generation of further hydrogen which will be consumed by the fuel cell or electrodes module, etc.

[0105] Of course, as in the previous embodiments, the embodiment shown in Fig. 32 is not limited to the use of borohydride compounds as the source of hydrogen gas or the self- regulating hydrogen generation device of the present invention. Non-limiting examples of substances which may be used instead of or in combination with one or more borohydride compounds include metal hydrides and alumohydrides such as, e.g., compounds of formulae MeH (Me = alkali metal, in particular Li, Na and K), Me'H₂ (Me' = Zn or an alkaline earth metal such as, e.g., Be, Mg, Ca, Sr and Ba) and MeAlH₄ (Me = alkali metal, in particular Li, Na and K). Generally speaking, any substance or compound which is at least somewhat soluble in the liquid which is present in the at least first chamber, is stable per se under ambient (and, if needed, substantially moisture-free) conditions and can be decomposed (e.g., catalytically and/or thermally) to form hydrogen gas is suitable as a hydrogen source for use in the present invention. [0106] The catalytic element 606 can be, by way of non-limiting example, a generally circular-shaped planar member having one side coupled or fixed to a surface of the housing cover 601b and an opposite facing side which is configured to interact with the fuel composition (see Fig. 33). The catalytic element 606 may, for example, comprise one or more of the following as the catalytically active material: Pt, Pd, Ru, Rh, Ir, Au, Co, Fe, Ni (preferably as zero valency metals and/or oxides). The catalytically active material is preferably carried by a high surface area support, thereby forming the element 606. By way of non-limiting example, the catalytic element 606 may occupy from about 10 % to about 90 % of the volume of the chamber 603. The element 606 is preferably positioned one side of the device 600. The element 606 can also be configured such that a layer of catalytic material is arranged on one side (e.g., on the member SPM) of the device 600 and another layer of catalytic material is arranged on another or opposite of the device 600.

[0107] Examples of suitable materials for supporting the catalytically active material of the element 606 include different types of ceramic and carbon materials with a high surface area. The catalytic element 606 may be present in various forms and shapes including, e.g., a sheet, a plate, a disk of the type shown in Fig. 32, a honeycomb structure, granules, etc. [0108] The hydrogen generator shown in Fig. 32 utilizes a solid fuel SF and a dilutant D which are stored in the housing 601a/601b. During storage or stand-by mode (no hydrogen consumption by the fuel cell) the fuel composition and the catalytic element 606 are separated by the shutter system and, as a result, hydrogen is not produced (Fig. 32). In working mode, however, the fuel composition and the catalytical element 606 interact by virtue of the member

DSM allowing the fuel composition to contact the catalytic element 606 (Fig. 33). Thus, the device functions with different modes depending on whether the shutter system is moved to the closed position (Fig. 32) or the opened position (Fig. 33), and also functions in different modes based on changes in the hydrogen gas volume resulting from the consumption of hydrogen gas by the fuel cell. As with previous embodiments, hydrogen is produced as result of fuel hydrolysis on the catalyst area (Fig 33). Furthermore, if and when the pressure increases in the chamber 603 more than a predetermined amount (e.g., such as might occur in an emergency situation) a valve (not shown) can open so that the pressure is released. The valve may also allow liquid fuel to flow out of the housing 601a in certain conditions.

[0109] Figs. 32 and 33 thus shows a shutter type hydrogen generator in a storage or stand-by mode with hydrogen not being produced (Fig. 32). Fig. 33 shows the shutter type hydrogen generator of Fig. 32 in an operating mode with hydrogen being produced and consumed by the fuel cell.

[0110] Examples of suitable materials for member SPM include plastics and metals such as, e.g., stainless steel. The member SPM may be present in various forms and shapes including, e.g., a symbol-shaped structure of the type shown in Fig. 32, etc.

[0111] Examples of suitable materials for deformable member DSM include plastics such as, e.g., elastomers such as resin, silicone, etc, or rubber materials. The member DSM may be present in various forms and shapes including, e.g., a plate, a sheet, a disk-shaped member, etc.

[0112] Examples of suitable materials for member CPM include plastics including, i.e., elastomers such as, e.g., resin, silicone, etc., and metals such as, e.g., stainless steel. The member CPM may be present in various forms and shapes including, e.g., a t-shaped structure of the type shown in Fig. 32, etc.

[0113] Examples of suitable materials for biasing member BM include plastics or rubber materials such as, i.e., elastomers such as, e.g., resin, silicone, etc,. The member BM may be present in various forms and shapes including, e.g., a plate, a sheet, a disk-shaped member, etc.

[0114] Examples of suitable materials for member RRM include plastics and metals such as, e.g., stainless steel. The member RRM may be present in various forms and shapes including, e.g., a ring-shaped structure of the type shown in Fig. 32, etc.

[0115] Figs. 45-48 schematically shows a vehicle having an electric motor drive system, a battery system, and a fuel cell system of the type described herein. The vehicle includes wheels W, an electric motor M, e.g., a DC motor, which is utilized to drive the wheels W, a battery system BS including one or more storage cells, and a fuel cell system FCS utilizing one or more of the hydrogen generators and fuel cells according to the present invention. Fig. 45 shows one possible mode of operation wherein the fuel cell system FCS supplies electrical power (whose flow is indicated by arrows) to a main switch system SCS which directs power to the battery system BS for charging the battery system. An electronic control system (not shown) can be provided to control the switch SCS. Fig. 46 shows another possible mode of operation wherein the fuel cell system FCS supplies electrical power (whose flow is indicated by arrows) to a main switch system SCS which directs power to the motor M. An electronic control system (not shown) can be provided to control the switch SCS. Fig. 47 shows another possible mode of operation wherein the fuel cell system FCS supplies electrical power (whose flow is indicated by arrows) to a main switch system SCS which directs power to the motor M and to the battery system BS. Fig. 48 shows another possible mode of operation wherein the fuel cell system FCS does not supply electrical power (whose flow is indicated by arrows) to a main switch system SCS, and instead the switch SCS directs power to the motor M from the battery system BS. [0116] Fig. 49 schematically shows a vehicle having an electric motor/generator drive system, a battery system, and a fuel cell system of the type described herein. The vehicle includes wheels W, an electric motor/generator MG, e.g., a DC motor/generator, which is utilized to drive the wheels W, a battery system BS including one or more storage cells, and a fuel cell system FCS utilizing one or more of the hydrogen generators and fuel cells according to the present invention. Fig. 49 shows one possible mode of operation wherein the fuel cell system FCS supplies electrical power (whose flow is indicated by arrows) to a second main switch system SCS_∑ which directs power to the motor/generator MG as needed. The motor/generator MG provides power to the battery system BS as needed and/or when advantageous which power is diverted by a first main switch SCSi. An electronic control system (not shown) can be provided to control the switches SCSi and SCS₂. Of course, other modes are possible such as, e.g., the fuel cell system FCS supplying electrical power to switch SCS₂ which directs power to the battery system BS when power is not being supplied by the motor/generator MG.

[0117] One non-limiting way in which the above-noted system(s) can be utilized include the following. Initially, the required vehicle start energy is provided by battery system BS. From initial acceleration to low speed, the motor M or motor/generator MG provides the required vehicle power, and this power can be augmented by the fuel cell system FCS. When the battery system BS is determined to be running low, it can be recharged automatically using the fuel cell system FCS. During deceleration/braking, the motor/generator MG can generate power by converting wasted kinetic energy into electricity for the battery system BS. At the same time, the battery system BS can be recharged automatically using the fuel cell system FCS. Of course, the vehicle can utilize conventional brakes for sudden stop conditions. At a stop or parking condition, the fuel cell system FCS can turn off to prevent hydrogen from being spent and/or to conserve fuel. In this case, the motor M or motor/generator MG stands silently ready for action. When action (e.g., restart) does finally occur, the energy is again supplied by the battery system BS.

[0118] In any of the embodiments disclosed herein such as the embodiment shown in

Figs. 1 1 and 12, the fuel cartridge can comprise solid fuel briquette covered in a hermetic plastic package. The fuel cartridge containing the solid fuel is placed into the hydrogen generator, is opened, and finally is activated by dilutant (e.g., water). The basic hydrogen generation reaction can be:

NaBH₄ + 2H₂O = NaBO₂ + 4H₂

The solid fuel/water ratio can depend on the fuel composition and may be from about 1 : lto about 1 :3 by weight. The water which may be used can be that from a regular water-supply source. In an emergency, it is even possible to use water from other sources, such as a lake, a river, seawater, etc. The hydrogen generator can be initially charged and/or provided with the solid fuel and water at a, e.g., a charging station. The hydrogen generator can also be recharged by, e.g., pumping out the spent or used contents and collecting the same for the further use. In an emergency, the spent contents may even be discharged to the environment and/or to a landfill system because the contents or spent fuel is deemed to be ecologically safe. Preferably, the spent fuel is collected and regenerated. Non-limiting examples of ways of regenerating the spent fuel include: the spent fuel can be used as a fuel component for generating power at a recycling center; the spent fuel (borates) can be converted and/or broken down into raw materials for different applications, for example, detergents, cosmetics, etc. Preferably, the spent fuel is converted into components which can again be used in a hydrogen generators. [0119] Hydrogen generators produce and supply hydrogen as required. One benefit of the hydrogen generators of the present invention, as compared with conventional hydrogen supplying systems (balloon), relates to the fact that they are self regulating and are a self contained system which minimizes infrastructure issues and provides for more efficient implementation.

[0120] Alternative chemical hydrides and borohydrides may be used and may include the following fuel active components: LiBH₄, NaBH₄, KBH₄, LiAlH₄, LiH, NaH, KH, MgH₂. [0121] The fuel cell which can be used with the hydrogen generators according to the present invention can be of any type which produces power from hydrogen gas and preferably has a power range from about 200W to about 120OkW. In the case of a vehicle utilizing an electric motor/generator, the electric motor/generator can be of any type but preferably functions in the power range of between about 200W and about 120OkW. Preferably, the fuel cell power range is substantially the same as that of the electric motor/generator. With regard to the battery system, any rechargeable battery cells can be utilized, but preferably have a power capacity of between about 200W and about 120OkW.

[0122] Fig. 50 schematically shows an overall system for generating electrical energy and for recycling/reusing spent components thereof in the system. The system utilizes a vehicle power system which receives electrical power from a fuel cell. The fuel cell receives hydrogen gas from a hydrogen generator. A fuel cartridge is utilizes to charge or supply the hydrogen generator with fuel such as, e.g., solid fuel (and also optionally dilutant). Spent fuel from the fuel cell can be recovered and/or recycled and, using a fuel regeneration system, can be converted to fuel that can again be used in the fuel cartridge.

[0123] It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A self-regulating hydrogen generation device comprising:

(a) at least one first chamber for holding a liquid and at least one first substance which is a source of hydrogen and is at least partly soluble in the liquid;

(b) a catalytic member capable of catalyzing a reaction which involves the at least one first substance and results in the formation of hydrogen gas; and

(c) a first separation element which is liquid-permeable and capable of allowing liquid to pass from the first chamber into a second chamber and a second separation element which is substantially liquid-impervious and gas-pervious.

2. The device of claim 1, further comprising a floating member comprising the first separation element.

3. The device of claim 1 or 2, further comprising at least one of: a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and a second position wherein the liquid does interact with the at least one first substance; a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the catalytic member and a second position wherein the liquid does interact with the catalytic member; and a flexible container containing the liquid and being movable at least from a first position wherein the liquid does not interact with the at least one first substance and the catalytic member and a second position wherein the liquid does interact with the at least one first substance and the catalytic member.

4. The device of any one of claims 1 through 3, further comprising a shutter that is movable at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member.

5. The device of any one of claims 1 through 4, further comprising a floating member comprising a first a member that moves at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member.

6. The device of any one of claims 1 through 5, wherein the liquid comprises water.

7. The device of any one of claims 1 through 6, wherein the at least one first substance comprises at least one of a borohydride compound, a metal hydride compound, and a solid fuel.

8. The device of any one of claims 1 through 7, wherein the at least one first substance comprises at least one compound selected from NaBH₄, KBH₄, LiBH₄, NH₄BH₄, Be(BRj)₂, Ca(BJ-Lt)₂, Mg(BFLt)₂, Zn(BFLt)₂, Al(BRt)₃, polyborohydrides, (CH₃)₃NBH₃, and NaCNBH₃.

9. The device of any one of claims 1 through 8, wherein the at least one first substance comprises at least one compound selected from compounds of formulae MeH, MeAlH₄ and Me¹H₂ wherein Me = Li, Na, K and Me' = Be, Mg, Ca, Sr, Ba, Zn.

10. The device of any one of claims 1 through 9, wherein at least one of: the first chamber is adapted for holding the at least one first substance in undiluted or concentrated form and, physically separated therefrom, a liquid dilutant for diluting the at least one first substance prior to using the device for the generation of hydrogen; the first chamber comprises at least two compartments, a first compartment for holding the at least one first substance in undiluted or concentrated form and a second compartment for holding liquid dilutant for diluting the at least one first substance; and the first chamber comprises at least two puncturable or breakable containers, at least one of them holding the at least one first substance in undiluted or concentrated form and at least one of them holding liquid dilutant for diluting the at least one first substance.

1 1. The device of any one of claims 1 through 10, wherein the catalytic member comprises at least one of a transition metal in elemental form and a transition metal oxide.

12. The device of any one of claims 1 through 1 1, wherein the transition metal is selected from one or more of Pt, Pd, Ru, Rh, Ir, Au, Co, Ni and Fe.

13. The device of any one of claims 1 through 12, wherein the catalytic member comprises a catalytic substance arranged on a carrier.

14. The device of any one of claims 1 through 13, wherein the carrier comprises at least one of carbon and a ceramic material.

15. The device of any one of claims 1 through 14, wherein the carrier is present as at least one of a sheet, a plate, a honeycomb structure, a cylindrical structure and granules.

16. The device of any one of claims 1 through 15, wherein the first separation element comprises a hydrophilic membrane.

17. The device of any one of claims 1 through 16, wherein the first separation element has at least one of a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm.

18. The device of any one of claims 1 through 17, wherein the second separation element comprises a hydrophobic membrane.

19. The device of any one of claims 1 through 18, wherein the second separation element has a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm.

20. The device of any one of claims 1 through 19, wherein the second separation element comprises a membrane which has a gas permeability pressure which is not higher than a gas permeability pressure of a membrane which is comprised in the first separation element.

21. The device of any one of claims 1 through 20, wherein the membrane of the second separation element has a gas permeability sufficient to meet predetermined system hydrogen requirements.

22. The device of any one of claims 1 through 21, wherein at least the first chamber further comprises a pressure compensating system.

23. The device of any one of claims 1 through 22, wherein the pressure compensating system comprises a hydrophobic membrane.

24. The device of any one of claims 1 through 23, further comprising a valve system which can be activated to allow gas to exit the device.

25. The device of any one of claims 1 through 24, wherein at least a part of walls of the first chamber is flexible.

26. The device of any one of claims 1 through 25, wherein the device further comprises a water absorption element.

27. A self-regulating hydrogen generation device comprising:

(c) a floating member comprising a first separation element which is liquid-permeable and a second separation element which is substantially liquid-impervious and gas-pervious.

28. The device of any one of claim 27, wherein the liquid comprises water.

29. The device of any one of claims 27 through 28, wherein the at least one first substance comprises at least one of a borohydride compound, a metal hydride compound, and a solid fuel.

30. The device of any one of claims 27 through 29, wherein the at least one first substance comprises at least one compound selected from NaBH₄, KBH₄, LiBH₄, NH₄BH₄, Be(BRt)₂, Ca(BH4)₂, Mg(BtLt)₂, Zn(BH₄);., Al(BH₄)S, polyborohydrides, (CH₃)₃NBH₃, and NaCNBH₃.

31. The device of any one of claims 27 through 30, wherein the at least one first substance comprises at least one compound selected from compounds of formulae MeH, MeAlH₄ and Me⁵H₂ wherein Me = Li, Na, K and Me' = Be, Mg, Ca, Sr, Ba, Zn.

32. The device of any one of claims 27 through 31, wherein at least one of: the first chamber is adapted for holding the at least one first substance in undiluted or concentrated form and, physically separated therefrom, a liquid dilutant for diluting the at least one first substance prior to using the device for the generation of hydrogen; the first chamber comprises at least two compartments, a first compartment for holding the at least one first substance in undiluted or concentrated form and a second compartment for holding liquid dilutant for diluting the at least one first substance; and the first chamber comprises at least two puncturable or breakable containers, at least one of them holding the at least one first substance in undiluted or concentrated form and at least one of them holding liquid dilutant for diluting the at least one first substance.

33. The device of any one of claims 27 through 32, wherein the catalytic member comprises at least one of a transition metal in elemental form and a transition metal oxide.

34. The device of any one of claims 27 through 33, wherein the transition metal is selected from one or more of Pt, Pd, Ru, Rh, Ir, Au, Co, Ni and Fe.

35. The device of any one of claims 27 through 36, wherein the catalytic member comprises a catalytic substance arranged on a carrier.

36. The device of any one of claims 27 through 35, wherein the carrier comprises at least one of carbon and a ceramic material.

37. The device of any one of claims 27 through 36, wherein the carrier is present as at least one of a sheet, a plate, a honeycomb structure, a cylindrical structure and granules.

38. The device of any one of claims 27 through 37, wherein the first separation element comprises a hydrophilic membrane.

39. The device of any one of claims 27 through 38, wherein the first separation element has at least one of a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm.

40. The device of any one of claims 27 through 39, wherein the second separation element comprises a hydrophobic membrane.

41. The device of any one of claims 27 through 40, wherein the second separation element has a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm

42. The device of any one of claims 27 through 41, wherein the second separation element comprises a membrane which has a gas permeability pressure which is not higher than a gas permeability pressure of a membrane which is comprised in the first separation element.

43. The device of any one of claims 27 through 42, wherein the membrane of the second separation element has a gas permeability sufficient to meet predetermined system hydrogen requirements.

44. The device of any one of claims 27 through 43, wherein at least the first chamber further comprises a pressure compensating system.

45. The device of any one of claims 27 through 44, wherein the pressure compensating system comprises a hydrophobic membrane.

46. The device of any one of claims 27 through 45, further comprising a valve system which can be activated to allow gas to exit the device.

47. The device of any one of claims 27 through 46, wherein at least a part of walls of the first chamber is flexible.

48. The device of any one of claims 27 through 47, wherein the device further comprises a water absorption element.

49. A self-regulating hydrogen generation device comprising:

(c) at least one of: a shutter that is movable at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member; and a member that moves at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member.

50. The device of claim 49, farther comprising a first separation element which is liquid- permeable and capable of allowing liquid to pass from the first chamber into a second chamber and a second separation element which is substantially liquid-impervious and gas-pervious.

51. The device of any one of claims 49 through 50, wherein the liquid comprises water.

52. The device of any one of claims 49 through 51, wherein the at least one first substance comprises at least one of a borohydride compound, a metal hydride compound, and a solid fuel.

53. The device of any one of claims 49 through 52, wherein the at least one first substance comprises at least one compound selected from NaBH₄, KBH₄, LiBH₄, NH₄BH₄, Be(BKO₂, Ca(BRj)₂, Mg(BK_t)₂, Zn(BR_t)₂, Al(BR_t)₃, polyborohydrides, (CH₃)₃NBH₃, and NaCNBH₃.

54. The device of any one of claims 49 through 53, wherein the at least one first substance comprises at least one compound selected from compounds of formulae MeH, MeAlH₄ and Me'H₂ wherein Me = Li, Na, K and Me' = Be, Mg, Ca, Sr, Ba, Zn.

55. The device of any one of claims 49 through 54, wherein at least one of: the first chamber is adapted for holding the at least one first substance in undiluted or concentrated form and, physically separated therefrom, a liquid dilutant for diluting the at least one first substance prior to using the device for the generation of hydrogen; the first chamber comprises at least two compartments, a first compartment for holding the at least one first substance in undiluted or concentrated form and a second compartment for holding liquid dilutant for diluting the at least one first substance; and the first chamber comprises at least two puncturable or breakable containers, at least one of them holding the at least one first substance in undiluted or concentrated form and at least one of them holding liquid dilutant for diluting the at least one first substance.

56. The device of any one of claims 49 through 55, wherein the catalytic member comprises at least one of a transition metal in elemental form and a transition metal oxide.

57. The device of any one of claims 49 through 56, wherein the transition metal is selected from one or more of Pt, Pd, Ru, Rh, Ir, Au, Co, Ni and Fe.

58. The device of any one of claims 49 through 57, wherein the catalytic member comprises a catalytic substance arranged on a carrier.

59. The device of any one of claims 49 through 58, wherein the carrier comprises at least one of carbon and a ceramic material.

60. The device of any one of claims 49 through 59, wherein the carrier is present as at least one of a sheet, a plate, a honeycomb structure, a cylindrical structure and granules.

61. The device of any one of claims 49 through 60, wherein the first separation element comprises a hydrophilic membrane.

62. The device of any one of claims 49 through 61, wherein the first separation element has at least one of a thickness of from about 20 μm to about 250 μm and a mean and/or maximum pore size of from about 10 μm to about 100 μm.

63. The device of any one of claims 49 through 62, wherein the second separation element comprises a hydrophobic membrane.

64. The device of any one of claims 49 through 63, wherein the second separation element has a mean and/or maximum pore size of from about 0.02 μm to about 10 μm, preferably from about 0.2 μm to about 5 μm, and most preferably about 0.2 μm.

65. The device of any one of claims 49 through 64, wherein the second separation element comprises a membrane which has a gas permeability pressure which is not higher than a gas permeability pressure of a membrane which is comprised in the first separation element.

66. The device of any one of claims 49 through 65, wherein the membrane of the second separation element has a gas permeability sufficient to meet predetermined system hydrogen requirements.

67. The device of any one of claims 49 through 66, wherein at least the first chamber further comprises a pressure compensating system.

68. The device of any one of claims 49 through 67, wherein the pressure compensating system comprises a hydrophobic membrane.

69. The device of any one of claims 49 through 68, further comprising a valve system which can be activated to allow gas to exit the device.

70. The device of any one of claims 49 through 69, wherein at least a part of walls of the first chamber is flexible.

71. The device of any one of claims 49 through 70, wherein the device further comprises a water absorption element.

72. A hydrogen-based fuel cell which is adapted for being sealingly connected to the device of anyone of claims 1 through 26 and for receiving hydrogen gas therefrom.

73. A system of the self-regulating hydrogen generation device of anyone of claims 27 through 48 and a hydrogen-based fuel cell.

74. A system of the self-regulating hydrogen generation device of anyone of claims 49 through 71 and a hydrogen-based fuel cell.

75. A method of generating hydrogen gas in a self-regulating manner, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and at least one of: using the hydrogen gas thus formed for substantially preventing fresh liquid material from contacting the catalytic material when a predetermined threshold gas pressure is reached; and allowing the liquid to pass through a first separation element which is liquid-permeable from the first chamber into a second chamber and allowing hydrogen gas to pass through a second separation element which is substantially liquid-impervious and gas-pervious.

76. A method of generating hydrogen gas in a self-regulating manner, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and allowing a floating member comprising a first separation element which is liquid-permeable and a second separation element which is substantially liquid-impervious and gas-pervious to move relative to a liquid level inside the device.

77. A method of generating hydrogen gas in a self-regulating manner, wherein the method comprises contacting a catalytic material with a liquid material which is capable of forming hydrogen gas when contacted with the catalytic material and at least one of: moving a shutter at least from a first position wherein the liquid is prevented from interacting with the catalytic member and a second position wherein the liquid is allowed to interact with the catalytic member; and moving a member at least between a first position covering the catalytic member and a second position wherein the member is spaced from the catalytic member.