Control system for hydrogen generators

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It is a further object of the invention to provide a

CONTROL SYSTEM FOR HYDROGEN method of controlling the production of hydrogen. GENERATORS It is a further object of the invention to provide a hydrogen generator control system which can be

BACKGROUND OF THE INVENTION 5 turned on and shut off substantially instantaneously. This invention relates to hydrogen generators and, It is a further object of the invention to provide a more particularly, to a control system for hydrogen hydrogen generator control means which is adjustable

as to the rate at which hydrogen is generated.

Hydrogen generators which produce quantities of SUMMARY OF THE INVENTION relatively high purity hydrogen have several uses. The O hydrogen produced can be fed to a hydrogen consum genThe invention relates to a control system for a hydro ing device or it can be placed in a storage device which cathode and anofaqueous generator the type having a consumable anode, a electrolyte therebetween. The maintains it for future use. One type of consuming de generator is provided with a circuit means which ena vice is a fuel cell such as that used in a power generation 15 bles electrical current to pass between the anode and system. The fuel cell is an electro-chemical device cathode in addition to the electrolyte. The production wherein the energy released in the oxidation of a fuel, of hydrogen as well as the rate of production is regu such as hydrogen, is made directly available in the form lated by a control means in the circuit means. The of electric current. It is distinguished from a battery in trol means can be selectively operated to enablecon or that fuel is continuously or intermittently supplied to 20 prohibit current from passing between the anode and the cell and its electrodes are not consumed. During cathode.

operation, it is necessary to feed hydrogen over one In one embodiment of the system, a hydrogen con electrode of the cell to produce electric current. suming device is made part of the system. The hydro A fuel cell system can be equipped with an integral gen generator can then be made to produce hydrogen hydrogen source to operate the cell over a period of as only as the consuming device requires it by having the time. Such a system can be designed to have the hydro gen produced by a hydrogen generator at the fuel cell controldevice.

means monitor an output of the consuming

When the output reaches predetermined levels, site rather than having to rely on a hydrogen storage the control means can be set to automatically enable and facility for its needs. This is desirable from the stand disable the production of hydrogen. point of safety. In addition, the hydrogen generator can 30 be made demand responsive; that is, produce hydrogen BRIEF EDESCRIPTION OF THE DRAWINGS only as needed by the fuel cell, thereby eliminating the FIG. 1 is a schematic illustration of the hydrogen need for any type of hydrogen storage facility. generator control system incorporated into a fuel cell In demand responsive hydrogen generators, there are power generation system.

several aspects of the hydrogen generation system 35 FIG. 2 is a schematic illustration of the fuel cell stack which are important. It is desirable to precisely control which contains the control cell. the hydrogen formation process; that is, to start and stop the process substantially instantaneously. The gen 2 atFIG.3(a) is a detailed view of the control cell in FIG. a time when adequate hydrogen is supplied to the erator desirably should not have alag factor in provid stack and no hydrogen is being called for from the ing hydrogen to the system that utilizes it. Otherwise, hydrogen generator.

the continuous operation of the consuming device, such FIG.3(b) is a detailed view of the control cell in FIG. as a fuel cell, could be jeopardized. Similarly, the gener 2 at a time when there is inadequate hydrogen in the ator desirably should not have a lag factor in stopping control cell and the cell has called on the hydrogen the formation of hydrogen after the hydrogen require generator to produce additional hydrogen for the stack. ments of the system have been satisfied. Any excess 45 FIG. 4 is a schematic illustration of a plurality of hydrogen would have to be bled from the system or cartridge-type hydrogen generators within a drum. placed in some sort of storage facility. Having to bleed FIG. 5 is a view of the apparatus of FIG. 4 taken off excess hydrogen would waste a portion of the hy through section A-A.

drogen produced and make the generator somewhat FIG. 6 is a schematic illustration of one embodiment inefficient. 50 of the hydrogen generator cartridge. There are other important considerations such as the DETAILED DESCRIPTION OF THE rate of hydrogen production during the generator's NVENTION operation. The formation of hydrogen must be at a sufficiently high rate for the application intended. The Referring more particularly to the drawings, wherein rate of hydrogen generation may be required to vary 55 like reference numerals are used throughout to desig over time and, therefore, the control system should nate like elements, FIG. 1 schematically illustrates one have the capability of being adjustable. The disablement embodiment of a system using the hydrogen generator of the generator from producing hydrogen should be control system. The hydrogen generator control system complete when it is not intended to be in operation. It is disclosed herein can be used for any suitable purpose also desirable that the control system be simple, inex 60 where there is a requirement for hydrogen. It can be pensive and reliable in construction. used with a free-standing hydrogen generator appara It is a principal object of the invention to provide a tus, totally unattached and unintegrated into a larger hydrogen generator control system. system, having the purpose of simply generating hydro It is a further object of the invention to provide a gen for any use whatsoever. It can also be a part of a hydrogen generator control system which automati 65 larger system including a hydrogen consuming device cally regulates the operation of the hydrogen generator having a need for receiving and utilizing hydrogen. in response to an output of a hydrogen consuming de Purely for the purposes of convenience of description, W1Ce, the hydrogen generator control system is disclosed in

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association with a fuel cell herein. It should be under The hydrogen produced by generator 50 in the sys stood, however, that its use is not restricted to this tem shown in FIG. 1 is fed to fuel cell stack 11 through application. pipe line 12. In the case wherein hydrogen generator 50 The fuel cell system shown in FIG. 1 includes four is a stand-alone system, the hydrogen can be stored in major sub-systems sectioned-off in dotted-line boxes; any suitable container (not shown) connected to genera energy cell 10, load 8, controller 40 and hydrogen gen tor 50 by any suitable pipe line similar to line 12. erator 50. Energy cell 10 has at least one fuel cell and is The configuration of generator 50 and the manner by depicted here as having a plurality of individual fuel which it forms hydrogen is now discussed with refer cells arranged in one or more stacks. The term “fuel cell 10 ence to FIGS. 4-5. The generator, in this embodiment, stack' means an arrangement whereby more than one has a cartridge holding means, drum 52, with a plurality individual cell is placed back-to-back in a stack fashion. of cartridges 60 located therein. The drum, when used Each cell can include a catalytic fuel electrode, to with a system such as that depicted in FIG. 1, may be which hydrogen is fed, a catalytic oxidant electrode, to permanently attached to the fuel cell system main frame which air is fed, and an electrolyte member therebe (not shown). The drum may have therein a means for tween. The system requires no moving parts since air is 15 locating and mounting cartridges 60 such as locators 53. supplied by diffusion and water created by the cells is The locators can be made of any suitable material such vaporized and drained from the cell stack by wicking. as an electrically insulating material. In this embodi Hydrogen is supplied to the fuel cells by the hydrogen ment, the interior bottom surface of the drum contains a plurality of cartridge locators 53 which facilitate the generator. Individual fuel cells can be of any suitable 20 insertion type. For instance, they can obtain an electrolyte of the slightly larger of cartridges 60 in the drum. They have a solid polymer type and a stack construction of the bi opening than the periphery of the car polar type as disclosed in U.S. Pat. No. 4,175,165. tridges so that the cartridges can be inserted. The drum The stack has a means for receiving a supply of hy also provides electrical separation for the plurality of drogen, line 12, and a means for removing excess fuel, 25 cartridges.

bleed line 13. The bleed line is only a precautionary hose Each cartridge in the drum has a pipe means, such as measure in the present system. Since the hydrogen gen allow 71, or merely an opening, which is adapted to erator is a demand responsive one, it is unlikely that releasedthefrom hydrogen produced by the cartridge to be the cartridge to feed line 12 to be fed to much excess or waste hydrogen would be created. The the fuel cell stack is connected to controller 40 by electrical 30 bodiment, mounted Controller fuel cell stack. 40 is shown, in this em to the drum and the cartridges and line 43 and is also connected to load 8 by electrical line controller are shown as being electrically wired, in 16. The purpose of controller 40 is to turn the hydrogen series fashion, by electrical wires 42. The cartridges are generator on and off, and to regulate the rate of hydro wired to each other and across the control means, or gen generation. Although nonessential, energy cell 10 switch or relay, of controller 40 so may also have an electrical energy storage means 15 35 electrical circuit is made between that one continuous the cartridges and which is connected to electrical line 16 between the stack and the load. switch. When the switch is open, no current is possible The purpose of stack 11 is to generate electrical en closed,through this circuit. However, when the switch is ergy or power to be used by load 9. The load, here current flows through the circuit. Basically, the cartridge contains a consumable anodic depicted simply as containing device 9, can be any type 40 material, of load requiring electrical energy to operate. One par lyte therebetween. a cathodic material, and an aqueous electro ticular use for the presently described fuel cell system is the circuit betweenItthe also contains a means to complete anodic and cathodic materials, as a power source for an ocean weather buoy which is in addition to the electrolyte, when hydrogen is to be placed in remote regions and is expected to be deployed generated thereby enabling electrical current to flow in service for long periods of time. The devices of the 45 through the electrolyte between the anodic material buoy commonly needing a source of electrical energy and cathode. The generator relies at least partially on are those that collect, store and transmit weather data to the process of anodic corrosion to produce hydrogen. satellites, ground stations, or ships. Fuel cell systems are The process of producing hydrogen is started simply by ideal for this purpose since they can be made compact, completing the circuit between the anode and cathode reliable, and self-regulating. Since such buoys do a vari 50 of the generator and allowing current to flow therebe ety of tasks, load requirements change over a period of tween. Once the process begins, hydrogen is formed time for the fuel cell stack. It is because of the varying through the rapid anodic and chemical corrosion of the load profile over a period of operation that it may be anodic material. Hydrogen bubbles form and rise to the desirable to include electrical energy storage means 15, top of the electrolyte. The process is stopped or dis such as a surge battery, to carry the load requirements 55 abled by simply breaking the circuit between the anode through periods of operational bursts. and cathode.

In this embodiment, controller 40 enables hydrogen The anodic material can be any suitable material generator 50 to be regulated directly by the hydrogen useful for the purpose intended with a negative electro requirements of the stack. The hydrogen generator is chemical potential relative to hydrogen. Suitable mate turned on and off and regulated by controller 40. Con rials include magnesium, aluminum, and alloys of mag troller 40 can be any suitable device that operates to nesium or aluminum such as those formed with manga control the generator in the manner intended. For in nese, zinc, iron, aluminum, and the like. These materials stance, it can be a switch means, or relay 41, that is able and other suitable materials are commercially available to monitor, through line 43, the electrical energy output from, for instance, Dow Chemical Company, Midland, of a control cell 14 shown in and described in conjunc 65 Mich. A product such as magnesium hydroxide is tion with FIGS. 2 and 3. The level of output from the formed and remains in the cartridge to be removed with control cell is monitored by the controller which, based the spent cartridge. The cathodic material can be any on the output, turns the hydrogen generator on and off. suitable material useful for the purpose intended. Suit

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able materials include steel, stainless steel, nickel-plated Screwed, water added, and the cap replaced, to activate steel, platinum, etc., having a low over-voltage for hy the cartridge a few hours before intended use. drogen discharge. The electrolyte can be any suitable The configuration and geometry of the cartridges are material useful for this purpose such as a conductive such to produce the desirable features of high energy aqueous liquid which is preferably non-corrosive. One density, high rate of hydrogen generation, high utiliza suitable material is salt water. tion of reactants and fast response time for turning the While the circuit connecting the anode and cathode generator on and off. The preferred embodiment of the of a cartridge remains uncompleted or in a state of high cartridge, as depicted in the Figures, is to make it sub resistance; that is, when the control means is set so that stantially cylindrical. The axis of the cylinder is pre the circuit between the anode and cathode is broken or O ferred to be substantially vertical when in use and the non-continuous, the anodic material passivates in the height of the cartridge, and particularly the anodic and electrolyte and essentially no meaningful amount of cathodic materials, is large relative to its diameter. hydrogen is formed. In other words, there is no self-dis Thus, for example, in FIG. 6, container wall 68 is in the charge during the time the circuit means is non-continu 15 shape of a cylinder standing on its end and anodic mate ous. On the other hand, when the circuit connecting the rial 62 and mesh 64 are also cylinders substantially con anode and cathode is complete; that is, when the control centrically located within the container. The cartridge means is set so that the circuit between the anode and is preferably in a substantially vertical orientation when cathode is continuous, the passivating layer on the an in use in order to have the electrolyte contact the whole surface of the anodic material and to have the rising odic material breaks down and rapid anodic and chemi hydrogen cal corrosion takes place to produce hydrogen. bubbles cause a circulation of the electrolyte A preferred embodiment of the compact, replaceable and keep it well-distributed in the container. Although cartridge is shown in FIG. 6. The cartridge includes the cartridge described herein is essentially cylindrical in configuration, it should be understood that the car container 68 which holds an anodic material 62 and electrolyte 72. The anodic material has a wire 61 therein 25 tridge or any of its various elements can be made in any which can carry the electric current. The container tended. shape which will operate in the manner in suitable further has steel sheet or mesh material 64 which serves as a cathode. Electrical leads 67 connected to wire 61 react The use of magnesium and alloys of magnesium to and steel mesh 64 are part of the electrical circuit that generationwith salt water is particularly attractive for the of hydrogen. Magnesium provides a high contains controller 40. Leads 67 are the circuit means 30 energy density, is economical on a kilowatt-hour basis for enabling electrical current to pass between the and the magnesium hydroxide formed from the reaction anode and cathode in addition to the electrolyte. presents no particular disposal problem. Most impor The cartridge also includes base 63 and spacer 65 tantly, however, magnesium is a safe material to use for which hold the container, steel mesh and anodic mate this purpose based on the fact that the reaction can be rial in place relative to each other and electrically insu 35 readily controlled.

lated from each other. Spacer 65 has holes or other Controller 40 enables hydrogen generator 50 to be passage means therein which enable the hydrogen regulated directly by the hydrogen requirements of the formed by the cartridge to rise to the top of the car stack. The hydrogen generator is turned on and off by tridge in the vicinity of cap 70 and then up through hose controller 40. Controller 40 can be any suitable control means 71 which feeds it into pipeline 12. Alternatively, 40 means, switch or relay that is able to regulate the pas hose means 71 can be merely an opening in the top of sage of current through the circuit means in response to the cartridge from where the hydrogen rises into drum demand for hydrogen. The demand for hydrogen can 52 to pipe line 12. be indicated by monitoring a measurable output of the Although steel mesh 64 is preferred for high rate of consuming device, the fuel cell in this embodiment. A hydrogen generation, it is not necessary to the car 45 measurable output can be electrical energy, such cur tridge. In an alternative embodiment, the mesh is elimi rent or voltage or power levels, pressure levels, temper nated and container 68, if made of a suitable cathode ature levels or any other suitable operational character material, can become the cathode. In this case, line 67 istic. In this embodiment, electrical voltage level of the would be connected to the container wall instead of the fuel cell's control cell is used as the measurable output. steel mesh material. In a further embodiment, the con 50 One electrical device found useful for this purpose is tainer can be made of any material to hold the electro a mercury-wetted contact relay manufactured by C. P. lyte which is coated on its inside with a suitable cathode Clare & Company, Chicago, Ill. 60645. It is stock num material which is connected to line 67. The base can be ber HGS 1015 identified in the “Electronic Engineers any strong material such as polyethylene. Similarly, the Master Catalog/EEM 77-78,” Volume 2 (20th Edition). spacers can be any suitable material such as a PVC 55 This switch has a "Must Operate Voltage (vdc)' of material. approximately 0.6. Controller 40 receives the electrical The anodic material can be made of an extruded output, energy voltage, on electrical line 43 from the magnesium that is available commercially from Dow control cell and operates to close the switch and enable Chemical Company. The mesh can be made of an ex current to pass through the circuit means to produce panded carbon steel material. The electrolyte can be 60 hydrogen. In this embodiment, hydrogen is produced salt water with the concentration of the salt solution until the voltage output of the control cell reaces ap being between about 0.1% and about 20%. It is pre proximately 0.9. Normal operating voltage of the con ferred to have the salt solution concentration between trol cell is approximately 1.0.

about 2% and about 10%. The cartridges can be stored FIG. 2 illustrates a stack of fuel cells, representative without the water being added until just prior to use. 65 of stack 11 in FIG. 1. The stack has a control cell shown The shelflife of the cartridge would be indefinite in this as end cell 14 in the stack. It is noted that in this embodi case. If the cartridges already have the salt in the con ment the stack is preferably arranged with the laminates tainer, the cap can be removed such as by being un extending in the horizontal direction to readily accom

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modate the flow and distribution of hydrogen through including control unit 14, is of normal operating voltage the stack including control cell 14, Hydrogen is fed into and current. FIG. 3(b), on the other hand, represents the stack through hydrogen feed line 12. Thus, fuel celi the stack condition wherein there is not sufficient hy stack 18 includes a plurality of back-to-back individual drogen to operate all cells at normal operating output. fuel cells 31 and end cell or control cell 14, At this point in the system's operation, control cell 14 is Hydrogen brought in through feed line 12 is distribe suffering substantially all of the hydrogen shortfall in uted to the fuel cells in the stack by upper passageway the stack because of the location of the control ceili 25 and lower passageway 26 as shown by the arrows. relative to the hydrogen line 12 and the action of baffle As the hydrogen enters upper passageway 25, it flows member 19. In this condition, the electrical energy out across and through passageway 25 all the way to baffle 10 put of fuel cells 31 remains at full normal operating plate 19. At the same time, hydrogen is allowed to flow levels since there is adequate hydrogen in this part of down through individual fuel cells 31, with the excep the stack. However, the electrical energy output of the tion of control cell 14, to lower passageway 26. The control cell has fallen off due to lack of fuel. hydrogen in upper passageway 25 is not allowed to flow Controller 40 receives, or monitors, the signal or into control cell 14 directly because of the presence of 15 output of the control cell. In this embodiment, voltage baffle plate 19. As sufficient hydrogen is fed in through drop off is relied upon to indicate the drop offin output supply line 12, it completely fills upper passageway 25, of control cell 14 due to an insufficient supply of hydro lower passageway 26 and all fuel cells 31. gen in the stack. If the normal operating voltage of the The hydrogen flows eventually from lower passage control cell is 0.8 volts when operating with sufficient way 26 underneath baffle 19 and then begins to fill 20 fuel, any voltage substantially less than 0.8 volts can be control cell 14. For control cell 14 to be completely relied on to indicate the insufficient hydrogen condi filled with hydrogen, all fuel cells 31 are substantially tion. Any suitable voltage level below 0.8 volts can be filled beforehand. After sufficient hydrogen is placed chosen to activate hydrogen production merely by into the stack to completely fill the cells, including selecting the particular voltage that activates control control cell 14, any excess hydrogen can be bled out of 25 means 40.

the stack as shown in FIG. 2. Fuel cells, like other devices, cannot be relied on to The stack shown in FIG. 2 includes fuel cells 3 and maintain exactly the same operating characteristics control 14 as being contained between two end mem from the time they are first placed in use to the end of bers 20. The electrical energy output of the stack, with their useful lives. As a result, normal operating output, the exception of control cell 14, is collected by conven 30 as well as other factors such as the output over a range tional collection plates (not shown) in members 20 and of operating fuel quantities and output current, can vary brought out of the stack through line 16. The electrical with time. The predetermined level of output at which output of control cell 14 is brought out of the stack the control cell most reliably indicates the need for separately, in this embodiment, to controller 40 through more hydrogen in the stack, taking into account these line 43. Although the control cell is shown as a dedi 35 aging factors in cell operation, is at approximately 0.6 cated cell having its output directed only to controller volts. This is depicted in FIG. 3(b). 40 in this embodiment, it is understood that the control Controller 40 completes the circuit means between cell output could also be used to supply electricity to the anode and cathode. At this point the generator is the load. enabled to produce more hydrogen for the stack. When The purpose of baffle plate 19 is to assure that suffi the voltage output of the control cell exceeds a second cient hydrogen is available in all fuel cells 31 between predetermined level, for instance, 0.8 volts, controller control cell 14 and hydrogen input line 12 to operate at 40 automatically disables the fuel generator by prohibit normal operating voltage before filling up control cell ing current from passing through the circuit means. 14. As a result, the electrical energy output of control Upon start up of the system, hydrogen is generated in cell 14 brought to controller 40 through suitable electri 45 generator 50 and applied to stack 11 through feed line cally separate lines, shown as line 43, drops off from its 12. This start up process can be controlled external to normal operating level when there is insufficient hydro the fuel cell system by any convenient manner such as gen in the control cell. This occurs before the output by having the operator manually override controller 40 level of the other cells in the stack reaches the point of so that the generator is operated until the electrical insufficient hydrogen. This drop off of output in the 50 energy output of the fuel cell stack is at its normal oper control cell is monitored and detected by controller 40. ating level. At this point, the operator allows controller Controller then enables current to pass through the 40 to take charge of the system. Since there is sufficient circuit means thereby producing more hydrogen to the hydrogen in the stack and all cells are operating at entire stack. about normal output, controller 40 disables the hydro FIGS. 3(a) and 3(b) represent detailed views of the 55 gen generator. The fuel cells continue to operate at interface between control cell 14 and the cells in the rest normal level until the overall hydrogen supply in the of the stack. In these figures, each individual fuel cell stack is consumed to the point that less than intended contains cathode 22, anode 23 and ion exchange mem hydrogen is left in control cell 14. This is detected by ber 21. The fuel cell laminate is generally designated as the controller and the hydrogen generator is turned 24. Upper passageway 25 and lower passageway 26 60 back on.

allow distribution of hydrogen through all the cells in Any suitable means can be used to automatically have the stack. Hydrogen is distributed to individual fuel controller 40 call for more hydrogen from generator 50 cells by fuel manifold 27 while air is brought through when the consuming device needs it. the fuel cells by air manifold 28. As mentioned above, a suitable device for controller FIG. 3(a) represents the stack condition wherein 65 40 is the mercury-wetted contact relay manufactured by sufficient hydrogen is present in fuel cell units 31 and C. P. Clare and Company, Number. H651015. This de also control cell 4. In this condition, the electrical vice is particularly usable in the embodiment wherein energy output of all the individual cells in the stack, the hydrogen generator is demand responsive to the

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consuming device, the fuel cell, and the voltage level corrosion to generate hydrogen having an anode, a outputted by the fuel cell is being sensed. Other conven cathode and an aqueous electrolyte therebetween tional devices such as current and power sensitive con and a circuit means for enabling electrical circuit to trol means could be used to monitor the current and pass between the anode and cathode in addition to power level outputs, respectively, of the consuming the electrolyte, device and operate the hydrogen generator in the same (b) a hydrogen consuming device for receiving and ae. utilizing hydrogen produced by the hydrogen gene Furthermore, outputs other than electrical energy erator means, and related outputs can be used in a similar manner. For (c) a controller means for regulating the passage of instance, it is possible to use the pressure of the hydro 10 current through the circuit means in response to gen in the consuming device, or the line feeding it or its demand for hydrogen by the consuming device storage facility to indicate when additional hydrogen whereby hydrogen is automatically generated and pro should be produced. In this case, a conventional pres vided to the consuming device only as required by the sure sensitive controller would be used to enable cur consuming device.

rent to pass through the circuit means when the pres 2. The system as in claim 1 wherein the controller sure level indicated more hydrogen is needed. Suitable regulates the passage current through the circuit means conventional temperature sensitive devices also can be in response to a measurable output of the consuming used as a controller. device which is indicative of a need for additional hy The controller embodiment described herein inter drogen for operating the consuming device in the man acts with the consuming device and hydrogen genera ner desired.

tor in a demand responsive manner to form a feedback 3. The system as in claim 2 wherein the measurable system. A measurable output of the consuming device output of the consuming device is electrical energy. provides a signal to trigger hydrogen production. It is 4. The system as in claim 3 wherein the measurable understood that the controller need not operate in this output of the consuming device is a level of voltage. manner. For instance, the activation of the controller 25 5. The system as in claim 3 wherein the measurable could be carried out manually without any feedback output of the consuming device is a level of current. from the consuming device. Further, the controller 6. The system as in claim 3 wherein the measurable could be used with the hydrogen generator alone with output of the consuming device is a level of pressure. out any consuming device joined thereto. In this case, a 7. The system as in claim 3 wherein the measurable storage facility would be desirable to maintain the hy 30 output of the consuming device is a temperature. drogen produced until it is to be used. 8. The system as in claim 1 wherein the hydrogen The controller could also contain a rheostat means by generator means anode material includes magnesium, which the current flow in the circuit means would be aluminum or alloys of magnesium or aluminum. made adjustable. The hydrogen production would be 9. The system as in claim 1 wherein the hydrogen substantially proportional to the rheostat setting. The 35 generator means cathode material is steel. rheostat could also be used as a switch to totally shut off 10. The system as in claim 1 wherein the hydrogen production of hydrogen by setting it to where it prohib generator means electrolyte is salt water. its current from passing through the circuit means alto 11. The system as in claim 1 wherein the hydrogen gether. The rheostat could also be adapted to a continu generator means is a replaceable cartridge. ous hydrogen production application wherein the rheo 40 12. The system as in claim 2 wherein the consuming stat does not act to prohibit the passage of current in the device is a fuel cell means.

circuit means but simply serves to provide a continuous 13. The system as in claim 12 wherein the fuel cell control over the rate of production. means is a stack of fuel cells containing more than one The fuel cell system described in FIG. 1 is self-con individual fuel cell, one cell of which is a control cell, tained and self-regulating. The production of hydrogen 45 and the electrical energy output of the control cell is is carried out by a system that responds to the needs for used as measurable output.

hydrogen of the fuel cell stack. The production of hy 14. The system as in claim 13 wherein the distribution drogen is precisely matched to the needs of the fuel of hydrogen in the stack enables the output of electrical cells. The controller and hydrogen generator operate energy of the control cell to lessen prior to the electrical substantially instantaneously when hydrogen is re 50 output of the other individual cells in the stack. quired. The good response of the system requires little 15. The system as in claim 14 wherein the electrical bleeding off of excess hydrogen in the stack, except to output of the control cell is dedicated to the controller the extent that impurities which accumulate are re aS moved. 16. The system as in claim 12 wherein the measurable It should be understood that the foregoing descrip 55 output of the fuel cell means is the electrical energy tion is only illustrative of the invention. Alternatives output thereof.

and modifications in the structural and functional fea 17. The system as in claim 12 wherein the measurable tures of the hydrogen generator controller can be de output of the fuel cell means is the pressure of the hy vised by those skilled in the art without departing from drogen fuel therein.

the invention. Accordingly, the present invention is 60 18. The system as in claim 12 wherein the measurable intended to embrace all such alternatives, modifications output of fuel cell means is the temperature thereof. and variations which fall within the spirit and scope of 19. A system for controlling the generation of hydro the appended claims. gen comprising:

What is claimed is: (a) a hydrogen generator means of the type which 1. A system for controlling the generation of hydro 65 relies at least partially on the process of anodic gen upon demand comprising: corrosion to generate hydrogen having an anode, a (a) a hydrogen generator means of the type which cathode and an aqueous electrolyte therebetween relies at least partially on the process of anodic and a circuit means for enabling electrical current

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to pass between the anode and cathode in addition 24. The controller system as in claim 23 wherein the to the electrolyte, controller input means is a manual means operatively (b) a hydrogen consuming device for receiving and connected to the rheostat means. utilizing hydrogen produced by the hydrogen gen 25. A method for a hydrogen consuming device to erator means, and directly regulate the formation of hydrogen by its asso (c) a controller means for regulating the passage of ciated hydrogen generator of the type which at least current through the circuit means to provide hy partially relies on the process of anodic corrosion to drogen to the consuming device. produce hydrogen having an anode, a cathode, an aque 20. A system for controlling the generation of hydro 10 ous electrolyte therebetween and a circuit means for gen comprising: enabling the passage of electrical current between the (a) a hydrogen generator means of the type which prising: anode and cathode in addition to the electrolyte com

relies at least partially on the process of anodic (a) monitoring a measurable output of the consuming corrosion to generate hydrogen having an anode, a means, cathode and an aqueous electrolyte therebetween 15 (b) determining that the output is at predetermined and a circuit means for enabling electrical current level, and to pass between the anode and cathode in addition (c) enabling the passage of current through the circuit to the electrolyte, means in response to the output being at the prede (b) a hydrogen storage device for receiving storing termined level.

hydrogen produced by the hydrogen generator 20 26. A method for efficiently operating a hydrogen means, and consuming system having a hydrogen consuming means (c) a controller means for regulating the passage of and an associated hydrogen generator comprising: current through the circuit means to provide hy (a) producing and supplying hydrogen to the con drogen to the storage device. suming means by a hydrogen generator of the type 21. A controller system for regulating a hydrogen 25 which relies at least partially on the process of generator of the type that relies at least partially on the anodic corrosion to produce hydrogen having an process of anodic corrosion to produce hydrogen hav anode, a cathode, and aqueous electrolyte therebe ing an anode, a cathode and an aqueous electrolyte tween and a circuit means for enabling and dis therebetween comprising: abling electrical current to pass between the anode (a) controller input means for receiving a signal that 30 and cathode in addition to the electrolyte, hydrogen is desired to be generated, (b) monitoring the consuming means to determine (b) controller circuit means for enabling electrical when it is in need of additional hydrogen, current to pass between the anode and cathode in (c) disabling the operation of the fuel generator by addition to the electrolyte, and prohibiting the passage of current through the 35 circuit means when the consuming means does not (c) controller output means for regulating the circuit need hydrogen, and means to enable the passage of current there (d) enabling the operation of a hydrogen generator by through in response to a signal being received by allowing the passage of current through the circuit the controller input means. means when the consuming means does need hy 22. The controller system as in claim 21 wherein the drogen.

controller output means completes the circuit means in 27. The method in claim 26 wherein the enabling step response to a signal being received by the controller includes adjusting the amount of current allowed to input means. pass through the circuit means to produce a hydrogen 23. The controller system as in claim 21 wherein the at a given rate.

controller output means includes a rheostat means. 45 :: x: s