Patent Application
20220131214
The object of the application is to provide an improved fuel cell apparatus and system with a hydride-based hydrogen generator that is scalable to different power levels, have high energy density, and additional safety features to power various platforms of unmanned vehicles, portable devices, backup or emergency power, soldier power, residential power, etc. Scalability of the stated apparatus and system is stemming from the flexible integration of multiple units both for the fuel cell and hydride-based hydrogen generator. High energy density feature of the overall system is coming from (i) usage of electrochemical methods for generating the electrical energy within the stated power solution, (ii) utilization of a hydrogen-dense hydride material as the hydrogen source in order to power various applications, and (iii) use of a process that that favors the exothermic heat generation during the hydrolysis of the stated hydride material and the subsequent use of this exothermic heat to sustain the hydrolysis reaction. The stated fuel cell and hydride-based hydrogen generator are scalable both at the low-, medium-, and high-level power outputs. In particular, the application relates to a fuel cell based power system that can utilize the hydrogen gas generated from a solid hydride material (via its hydrolysis reaction with water vapor at high temperatures) that can be carried around either by an unmanned vehicle, by a person such as a camper, by an individual soldier, provide power to a group of individuals collectively (such as a group of campers, a squad or multiple squads of soldiers, etc.), or be placed inside the power box for the intended backup or emergency application, etc. Fuel cells are high efficiency devices and coupling such devices with a hydrogen generator system that utilizes a high energy density hydride material for the hydrogen source yield an overall system that combines the synergy of the both systems and reduces the overall system weight drastically compared to conventional battery technology and provides a high energy density power solution for whatever the intended application it is used for.
Currently, all of the essential power needed for various applications (such as various platforms of unmanned vehicles, portable devices, backup or emergency power, soldier power, etc.) is usually obtained by using Li-ion, Li-polymer, or some other relevant battery technology. Since the batteries have to carry the active material for anode and cathode electrodes regardless of the battery chemistry, the operational duration of the intended application is usually extended by carrying more batteries, though the final weight of the battery module becomes extremely heavy. Energy storage capacity of batteries are usually identified based on their specific energy density values and this parameter can be measured either as the energy storage capacity in a unit weight (Watt·Hour/kilogram) or unit volume (Watt·Hour/Liter) basis. As a rule of thumb, the higher the gravimetric energy density or volumetric energy density of the selected battery technology, the longer the application would be powered without recharging or replacing the depleted battery cells. Current state-of-the-art lithium batteries used in various applications have a gravimetric energy density of 120 to 180 Wh/kg values. Portable power applications (such as consumer electronics products, soldier power, camping and other recreational activity, etc.) for 1-person team to a few-person team would usually require a power output that is in the range of 0 to 100 Watts. As the size the team in terms of members grows (10-20 member camping group, a squad of soldiers with 8 to 24 soldiers, a platoon of soldiers with 16 to 50 members, etc.), the power consumption value can easily increase to multi-kilowatts. Various small to medium class of unmanned vehicles (fixed-wing UAVs, multi-rotor drones, VTOLs, etc.) usually utilize power in the range of 100 Watts to multi-kilowatts such as 10 kW and this power consumption is completely dependent on the maximum takeoff weight (MTOW) and architecture of the unmanned vehicle. Heavy-lift unmanned vehicles can consume power in the order of 10 kW to 100 kW. The electrical energy requirement of emergency/backup applications such as telecoms (critical communication network infrastructures in wireless, fixed, and broadband) can range from 250 W to 15 kW. Certain residential and stationary applications may require an electrical power of 25 kW to 1 MW. Even though conventional battery technologies can be used either as single module or in an array of modules in order to cover a large range of power production with high electrical efficiency for various applications, their low gravimetric energy density values (120 to 180 Wh/kg), high replacement costs, unpredictable life expectancy in harsh environments, and toxic disposal challenges have limited their usage. In layman's term, the definition of low-, medium-, and high-level power outputs can roughly be defined as 0-100 Watts, 0-100 kW, and 0-1 MW and the scope of this application is by no means limited to these definitions.
A fuel cell is an excellent portable power source of electricity because of its high energy density compared to conventional batteries. To increase the operational time of a battery-powered application, the battery capacity needs to be increased. The following section provides a comparison of fuel cell system to a lithium-polymer system for their weight, energy storage capacity, and operational time for a certain assumed power scenario. Assuming that a particular application is consuming 250 Watts (for example 22.2 V at 11.26 A) of electrical energy, a 7700 mAh lithium-polymer battery module would weigh 1.17 kg, store 170 Wh of electrical energy, have 146 Wh/kg gravimetric energy density, and would last 0.68 hours (see http://www.thunderpowerrc.com/AIR_BATTERIES/7700-mAhE/TP7700-6SE55). Increasing the battery system weight to 30 kg (by stacking up a large number of 7700 mAh modules), the operational time can be increased to 17.43 hours. Since the energy storage capacity of batteries is directly related to the quantities of the anode/cathode active material, the weight increase for batteries is almost linear. Fuel cells, contrary to the conventional batteries, do not have to carry the active material and it only needs a single fuel cell stack module to continuously generate power. To extend the operational time for the fuel cells, only the cylinder storage needs to be increased and adjusting the size of the cylinder and the overall system weight increase is minimal compared to the weight increase seen in a battery technology.
As it can be seen in the above-mentioned table, fuel cell systems can achieve very high gravimetric energy density values (such as 1001 Wh/kg for the above-mentioned case study, which is greater than 600% compared to LiPo battery's gravimetric energy density) and potentially provide significant improvements for the operational time or yield a much lighter system weight than the conventional battery based systems.
These fuel cells may be direct methanol fuel cell (DMFC), alkaline fuel cells, solid oxide fuel cell (SOFC) or proton exchange membrane fuel cell (PEMFC). Among these different fuel cell technologies, PEMFC is the most promising fuel cell technology because of its excellent electrochemical performance within the temperature envelope of −20 to 80° C. and high-power density for the fuel cell stack component (up to 5.5 W/cm2). With the use of ultralight-weight fuel cell stacks, such as HES' Aerostak products (https://www.hes.sg/aerostak), gravimetric energy density values greater than 1000 Wh/kg can easily be achieved at the overall system level depending on the form of the hydrogen (meaning how the hydrogen is stored). Multiple fuel cell systems can be integrated in series or parallel (form an electrical connectivity perspective) in order to generate the desired amount of electrical energy. For example, if a single fuel cell system is capable of generating 1.5 kW of electrical power, then integration of multiples of this same system would create multiples of 1.5 kW of electrical power, such as 10 units of 1.5 kW fuel cell system connected in series would produce a total of 15 kW of electrical power. Hence, an array of PEM fuel cell systems make this electrochemical technology very scalable for larger power output requiring applications.
PEMFCs utilizes hydrogen gas at the anode side and oxygen (from the ambient air) at the cathode side electrochemically, which creates an electrical voltage that can be used to generate electrical energy. Though, a major limitation for the use of PEMFCs has been the need for high-density hydrogen storage. Hydrogen can be initially generated as gas or liquid and then stored inside a properly designed cylinder at an off-site location or the hydrogen can be generated in the field in real time by using a solid hydrogen storing material such as hydrides. Currently available high-pressure cylinders are bulky in volume, heavy, and can store limited quantities of hydrogen gas due to their low working pressure. Most of the portable cylinders have volumetric capacity of several liters, weighs several kilograms, and have a working pressure of up to 700 bars. Despite the fact that liquid hydrogen storage option has a much higher energy storage capacity compared to gaseous high-pressure hydrogen storage option, large volume and mass for the storage vessel and boil-off issues prevented its widespread use for various applications. On the other hand, on-demand and real-time generation of hydrogen from solid materials such as hydride compounds have a large potential from an engineering feasibility for numerous applications (such as portable applications, various unmanned vehicles, emergency/backup power, etc.) due to easy extraction of the hydrogen approaches from the hydride material itself.
There exist a number of hydride materials that can be used for hydrogen gas generation such as sodium borohydride, ammonia borane, alanates, magnesium hydride, etc. Hydrolysis and thermolysis are the most common methods of extracting hydrogen from such hydride materials. Hydrolysis approach refers to the chemical reaction of hydride material with water (whether this is pure water, caustic water, or acidic water) with or without a catalysts bed. Thermolysis method refers to extraction of hydrogen from the hydride material with heat without using any other ingredients. Hydrogen gas generated with the thermolysis route usually requires the thermal decomposition of a known quantity of the hydride material (most of the time in the pelletized form) instantly and hence there is a need for a high-pressure vessel to contain the generated hydrogen gas. The weight of the high-pressure vessel usually is very high in order to provide a reasonable safety margin for its safe operation and hence not suitable for majority of portable power applications, unmanned vehicles (particularly unmanned aerial vehicles), etc. In short, hydrolysis method has been identified as a more promising approach for hydrogen generation from hydride materials due to its engineering feasibility and lightweight nature of the final hardware.
Kim and Lee, published an article “A complete power source of micro PEM cell with NaBH4 microreactor”, in Micro Electro Mechanical Systems, 2011 IEEE 24th International Conference. This micro PEM cell includes a micro reactor for hydrogen generation from NaBH4 alkaline solution. This technology uses highly caustic and hazardous chemicals such as sodium hydroxide or potassium hydroxide in order to stabilize the lifetime of the sodium borohydride material. Furthermore, the by-product of the sodium borohydride hydrolysis reaction is highly viscous and needs to be flashed out of the catalyst bed by using water, which creates additional logistics requirements for the intended applications. There is a need for a better hydride material that does not require use of hazardous chemicals or create additional logistics issues.
While ammonia borane has a higher hydrogen storage percentage compared to sodium borohydride, during the hydrolysis of the ammonia borane, ammonia gas is also generated, and the hydrogen stream needs to be cleaned from this ammonia gas contaminant (since this is a poisoning chemical for PEMFCs) before the generated hydrogen enters the fuel cell stack. This gas cleanup adds more complexity to the portable power device, increases its weight and volume, and hence makes it difficult to use for a wide range of power applications.
A hydride material that is based on magnesium can also be used for the hydrogen gas generation via the hydrolysis route. Hydrolysis reaction of MgH2 can either be classified as exothermic or endothermic. Depending on the amount of water used, the hydrolysis reaction mechanism changes drastically for the magnesium hydride powder (see Eqs. 1 and 2). Furthermore, the state of the water (liquid or steam) also affects the outcome of the hydrolysis reaction. Some of the most important hydrolysis reactions of MgH2 with water (regardless of the state of the water) can be given as:
MgH2+H2O→MgO+2H2(Delta H: −360 kJ/mol) Eq.1
MgH2+2H2O→Mg(OH)2+2H2(Delta H: −138.5 kJ/mol) Eq.2
Hydrolysis reaction of MgH2 with steam is highly exothermic when the molar ratio of MgH2 to water is kept at 1, meaning MgH2's number of moles is equal to steam's number of moles (see Eq. 1, hereinafter it is called exothermic MgH2 hydrolysis reaction). As the number of moles is increased for the water (see Eq. 2), the heat production becomes less (in layman's term, it is becoming more endothermic). Despite the fact that the Eq. 2 is theoretically considered to be exothermic in nature, but the amount of heat generated is not sufficient to sustain the hydrolysis of MgH2 when too much water is consumed, and it requires the use of an external power source to input an additional amount of heat in order to complete the hydrolysis reaction. To sum up, as it can be seen in Eq. 1 and Eq. 2, the amount of water used for the hydrolysis reaction drastically affects the quantity of the heat produced. Once the hydrolysis reaction is initiated with an initial heating, it will be advantageous to utilize this exothermic heat to its fullest in order to sustain the hydrolysis reaction without adding any additional external heat from an external power source such as a battery. For this reason, exothermic hydrolysis reaction pathway that is provided in Eq. 1 is the preferred pathway for this application to generate a significant amount of exothermic heat and then use this exothermic heat to sustain the hydrolysis reaction after the initial pre-heating step without any additional heat from an external power source.
This application utilizes the exothermic MgH2 hydrolysis reaction pathway by limiting the water usage to the desired stoichiometry range, which can be summarized as molar ratio of MgH2 to H2O being the range of 1-2, preferably in the range of 1 to 1.5, more preferably in the range of 1 to 1.25, even more preferably in the range of 1 to 1.1.
The following presents a summary to provide a basic understanding of the present application. This summary is by no means an extensive overview of the application and is not intended to identify key features of the application. Rather, it is to present some of the novel concepts of this application in a generalized form as a prelude to the detailed description that is to follow.
The present application is comprised of a fuel cell apparatus and system and a hydride-based hydrogen generator system with improved scalability in terms of power output and hydrogen gas generation. The proposed fuel cell system has high electrical efficiency and good scalability to assist a large number of applications. Hydride-based hydrogen generator utilizes a hydride material that has excellent stability across a wide temperature range, has a high hydrogen storage percentage capacity, excellent hydrogen extraction via high temperature steam hydrolysis route, and excellent scalability for producing any quantity of hydrogen flow rate depending on the reactor design used to generate the hydrogen. The synergy between these two systems ultimately yields an overall powering device that can be used for a wide range of applications without compromising the scalability or efficiency.
The fuel cell apparatus and system is comprised of a fuel cell, a balance of plant, and a fuel cell controller. The heart of a fuel cell is the fuel cell stack where the membrane electrode assemblies are grouped together either in series or in parallel. Membrane electrode assembly is comprised of an anode catalyst, a membrane, a cathode catalyst and the corresponding gas diffusion layers and gaskets. Hydrogen and oxygen reactants get consumed electrochemically at the anode and cathode catalysts, respectively. The stated electrochemical reaction produces an electrical voltage and hence power. The power range for the stated fuel cell apparatus and system is highly scalable and it is a function of the number of cells present in the fuel cell stack. This application intends to cover the following range of power: 0 Watts to 1 MW. While a single fuel cell system is capable of providing either 0 to 10 Watts, 0 to 20 Watts, 0 to 50 Watts, 0 to 100 Watts, 0 to 250 Watts, 0 to 500 Watts, 0 to 1000 Watts, 0 to 1500 Watts, 0 to 2000 Watts, 0 to 3000 Watts, 0 to 5000 Watts, 0 to 10000 Watts, 0 to 50000 Watts, 0 to 250000 Watts depending on the fuel cell stack technology (air cooled or liquid cooled), an array of multiple of a same fuel cell stacks that are connected either in parallel or in series can easily produce an electrical power output of 1 MW with the proper engineering. The nominal operation of “open cathode fuel cell stacks (also known as air-cooled fuel cell stacks)” require their usage at electrical efficiencies greater than 50% in order to increase their operational lifetimes. The balance of plant components is comprised of the following items: fuel cell casing, fuel cell stack manifold, fan, pressure regulator, pressure sensor, temperature sensor, supply valve, purge valves, gas stream cleaning filters, LCD display, hydrogen gas transfer plumbing, unused hydrogen and water purging plumbing, fuel cell stack conditioning electronics, and etc. (but not limited to those). The stated balance of plant components can be used as single or plural items in order to facilitate the safe operation of the fuel cell system to reliably produce the desired electrical power by consuming the hydrogen gas coming from the hydrogen generation system. The stated fuel cell system can be assembled as a single unit (meaning as a stand-alone unit) for ease of integration to a stand-alone hydrogen generation unit or it can be intimately assembled with the hydrogen generation unit in a more compact and ruggedized form factor.
The hydride-based hydrogen generation system is comprised of a water storage vessel, a hydride cartridge, and a balance of plant in order to generate sufficient quantity of hydrogen for the fuel cell apparatus and system stated in this application. The preferred hydride material is magnesium hydride, and the preferred hydrolysis reaction pathway is the exothermic MgH2 hydrolysis reaction (see Eq.1). The main functionality of the water storage vessel is to store the water supply in a storage area and transfer this water to the reaction chamber with the aid of a pump. The water storage vessel assembly can also be comprised of the following components: water tank, water pump, orientation-independent water movement mechanism, pressure sensor, temperature sensor, valves (with different functionalities), filters, buffer or condenser unit, a battery, essential plumbing to move the water into the hydride reactor and collect the hydrogen from the hydride reactor, and etc. A hydride cartridge is comprised of a reactor vessel, a vessel cap, a mounting plate to secure the input and output plumbing and connectors, a heater, and a number of porous and non-porous tubes located inside the reactor vessel with different functionalities. The reactor vessel has the main functionalities of containing the magnesium hydride fuel and all of the essential other reactor components needed to allow the water vapor or steam entering into the hydride reactor, allowing the hydrolysis reaction be carried very efficiently while utilizing the exothermic heat generated (from the exothermic MgH2 hydrolysis reaction) in order to sustain the hydrolysis reaction without inputting an extra amount of electrical energy from the small battery module or from any other external power source, and collect the generated hydrogen and remove the contaminants from the hydrogen stream. The cooling down of the hydrogen gas temperature to a level that is appropriate to the safe operation of the stated fuel cell apparatus and system, and transferring of this clean and cooled down hydrogen to the fuel cell is done with the cooling coil and other essential plumbing that reside between the hydride cartridge and the fuel cell. Depending on the desired operational time and also desired power output, the reactor portion of the hydride-based hydrogen generator can be designed to contain sufficient amounts of hydride material that would suffice to generate an electrical energy of 0 to 10 Wh, 0 to 30 Wh, 0 to 50 Wh, 0 to 100 Wh, 0 to 300 Wh, 0 to 500 Wh, 0 to 1000 Wh, 0 to 3000 Wh, 0 to 5000 Wh, 0 to 10000 Wh, 0 to 30000 Wh, 0 to 50000 Wh, 0 to 100000 Wh, 0 to 300000 Wh, and 0 to 1000000 Wh. An array of the same or different hydrogen generation system can be integrated with each other in order to produce the desired quantity of hydrogen gas flow that is needed for the intended application. The stated hydride-based hydrogen generator system can be assembled as a single unit (meaning as a stand-alone unit) for ease of integration to a fuel cell apparatus and system or it can be intimately assembled with the fuel cell apparatus and system in a more compact and ruggedized form factor.
In the following description, details are provided to describe embodiments of the application. It shall be apparent to one skilled in the art, however, that the embodiments may be practiced without such details.
Some parts of the embodiment have similar parts. The similar parts may have the same names or similar part numbers. The description of one similar part also applies by reference to another similar parts, where appropriate, thereby reducing repetition of text without limiting the disclosure.
Again referring to
Hydrogen produced in the reaction chamber 10 is supplied through a hydrogen outlet port or quick-disconnect coupling 13 located on the mounting plate 106 and flows into a hydrogen line 20; preferably, the hydrogen line 20 is located inside the manifold 109; thereafter inside the manifold 109, the hydrogen line 20 is tapped off to a pressure sensor 21 and a pressure relief valve 22. The hydrogen line 20 then goes into a cooling coil 120, which is disposed inside the water storage vessel 16, with an outlet of the cooling coil leading to a buffer tank 122. The hydrogen gas passes through the cooling coil 120 and is being cooled from a high temperature of about 100 to 600° C. (in the reaction chamber 10) to about 20-60° C.; any water that condenses out from the hydrogen gas is collected inside the buffer tank 122; the condensed water is recycled into the water storage vessel 16 via a recollection valve 126, which is operable by a signal from the controller 110 to a solenoid S1. Hydrogen flowing through an outlet 124 at the buffer tank 122 is connected to a purifying filter 130 before the pressure is controlled by the pressure regulator 4. The hydrogen supply upstream of the purifying filter 130 is controlled by a supply valve 128 and an accompanying solenoid S2. The supply valve 128 may be used to stop the hydrogen gas being supplied to the fuel cell 2 when the fuel cell 2 is being purged, for eg. at an end of a power generation cycle or at an end of a start-stop cycle, as determined by the controller 110 and/or user. The controller 110 is electrically connected to the fuel cell 2 by a cable 6.
The water storage vessel 16 is spill-proof. As seen from
The preferred hydride powder for this application is comprised of magnesium hydride (MgH2) material. To hydrolyse MgH2 powder 30 that is disposed inside the reactor vessel 102 (via exothermic MgH2 hydrolysis reaction, see Eq.1), the reaction chamber 10 is preferably pre-heated to about 80-100° C. The initial heating of the reaction chamber 10 is carried out by the controller 110 providing a signal to close a switch 162 connected to a heater port 163, which is electrically connected to the heater 36. It is essential that the heater 36 provides enough residential time to the water for its heating and conversion into steam and this can be achieved by manufacturing the heater 36 in spiral coil form. Initial power for the heater 36 is obtained from a battery 25 or another external power source. Once sufficient hydrogen is generated from the reaction chamber 10 and operation of the high energy density fuel cell apparatus and system with a hydride-based hydrogen generator 100 is sustainable, electric power generated from the fuel cell 2 is fed through the cable 6 to the controller 110. Hydrolysis of the MgH2 is controlled either by consumption of hydrogen gas at the fuel cell 2 (via monitoring of the hydrogen gas pressure inside the fuel cell 2 by reading the pressure value sensed by the pressure sensor 132) or by controlling the amount of water fed through the pump 15 according to a demand of an electric load 26 connected to an output port 165. In one embodiment, when the voltage V in the cable 6 exceeds that of the battery 25, a portion of or all of the electric power from the fuel cell 2 charges up the battery 25. In this application, it is intended to use the exothermic MgH2 hydrolysis reaction pathway and hence a temperature sensor 37, such as a thermocouple, monitors the temperature inside the reaction chamber 10. Signal from the temperature sensor 37 is fed to the controller 110, together with signals from the hydrogen pressure sensors 21 or 132. As seen from
The high energy density fuel cell apparatus and supply with a hydride-based hydrogen generator 100 assembly includes the following (but not limited to and some of the components are not shown in the figures for the sake of simplicity):
The reactor vessel 102 contains a dry magnesium hydride powder 30 disposed inside the vacuum-insulated double-walled reactor vessel 102 that offers excellent heat insulation. Vacuum insulated vessels are particularly well-suited for portable power applications. This allows the contents in the reactor vessel 102 to retain their heat for an extended period of time, while an exterior of the reactor vessel remains cool and safe to touch. Other non-portable power applications may not require the use of vacuum-insulated double-walled reactor vessel. The reaction between water and magnesium hydride produces hydrogen gas which is then supplied to the fuel cell 2 to generate useful (electric) energy to the user otr the intended application's load. The reactor vessel 102 contains the following components:
Now, operation of the hydride cartridge 105 that is located inside the hydride-based hydrogen generator system 3 is described: Upon switching on, water from the water storage vessel 16 is supplied in controlled amounts into the hydride cartridge 105 through the water pump 15. The heater 36 is powered up by the battery 25 (or another power source) to heat up the reaction chamber 10 and heat up the liquid water and convert this into a high temperature steam to promote the exothermic MgH2 hydrolysis reaction between the hydride powder 30 and the steam to produce H2 gas. When the reaction becomes optimized or stabilized, the exothermic nature of the hydrolysis reaction allows for self-sustainment of the hydrolysis reaction and no longer requires the aid of the heater 36. The H2 produced during the reaction is cooled from a high temperature range of 100 to 600° C., preferably of 200 to 400° C., more preferably of 300 to 400° C. (in the reaction chamber 10) to about 5-100° C., preferably to 10 to 50° C., more preferably to 20 to 40° C. before hydrogen flows through the manifold 109 towards to the fuel cell stack 2. At the fuel cell 2, H2 and O2 reactants are reacted with each other electrochemically and as a result, electrical energy is produced with high efficiency, which is then channeled to the electrical load 26.
Referring to the cylindrical embodiment design provided in
The start-up sequence for the hydrogen generation system can take almost up to 10 minutes. During substantially the first 10 minutes of the operation, the energy output from the high energy density fuel cell apparatus and system with a hydride-based hydrogen generator 100 is predominantly contributed by the battery 25 (or another secondary power source) while hydrogen builds up within the reaction chamber 10. When significant amount of H2 (flow) is generated from the exothermic MgH2 hydrolysis reaction to produce electric energy, fuel cell 2 takes over to supply electric power to the electric output port 165. The battery 25 together with any other rechargeable battery or electric load connected to the output port 165 would in-turn be recharged or powered by the electric energy produced at the fuel cell stack 2.
The controller 110 includes an algorithm that responds adaptively to the utilization level remaining in the hydride cartridge 105. For eg., if the hydride cartridge 105 is about half utilized, there is likelihood of water being present in the reaction chamber 10; in this case, more heat is required and the controller 110 algorithm responds adaptively to extend the heater's heating duration before more water is supplied into the reaction chamber 10.
The process of single hydrolysis reaction zone 172 occurring within a reactor vessel 102 with a microporous medium 168 (such as microporous tube) that has single steam injection point is described in
The process of multiple hydrolysis reaction zones 173 occurring within a reactor vessel 102 with a microporous medium 168 (such as microporous tube) that has multiple steam injection points is described in
The embodiments can also be described with the following lists of features or elements being organized into an item list. The respective combinations of features, which are disclosed in the item list, are regarded as independent subject matter, respectively, that can also be combined with other features of the application.
Item 1. A high energy density fuel cell apparatus and system with a hydride-based hydrogen generator comprising the following:
connecting a water pump to supply water from a water storage vessel to a reactor vessel, wherein a pump discharge line comprises a tubing with a predetermined rupture pressure range and a check valve;
thermally insulating the reactor vessel with a vacuum double wall and, on an exterior of the reactor vessel, surrounding the reactor vessel with a thermal insulator;
hydrolysing a hydride powder (based on the exothermic MgH2 hydrolysis pathway) disposed in the reactor vessel with a controlled amount of water supplied through the water pump to generate hydrogen gas on demand; and
directing the hydrogen gas to flow from an outlet of the reactor vessel to a high energy density fuel cell apparatus and system to generate electric power,
Item 14. The high energy density fuel cell apparatus and system with a hydride-based hydrogen generator system according to item 13, further comprising:
passing the hydrogen gas through a cooling coil disposed in the water storage vessel to cool the hydrogen gas to a predetermined temperature;
condensing water vapour in the hydrogen gas in a buffer tank, which buffer tank is disposed downstream of the cooling coil, so that the condensed water collected in the buffer tank is recycled back into the water storage vessel via a recollection solenoid valve,
Item 15. The high energy density fuel cell apparatus and system with a hydride-based hydrogen generator system according to item 14, further comprising:
purifying the hydrogen gas by passing the hydrogen gas through a purifying filter disposed downstream of the buffer tank,
Item 16. The high energy density fuel cell apparatus and system with a hydride-based hydrogen generator system according to any one of items 13-15, further regulating operation of the PEMFC with a controller, wherein the controller comprises an algorithm that responds adaptively to a utilization level remaining in the hydride cartridge,
Item 17. The high energy density fuel cell apparatus and system with a hydride-based hydrogen generator system according to item 16, wherein the battery allows hot-swapping of the reactor vessel when the hydride powder is depleted and the high energy density fuel cell apparatus and system with a hydride-based hydrogen generator is still operating,
Where the fuel cell apparatus and hydrogen generator can be assembled as separate systems and then integrated into a common housing or intimately assembled inside a common housing in order to facilitate the hot-swapping of the reactor vessel,
Item 18. A process for operating a high energy density fuel cell apparatus and system with a hydride-based hydrogen generator system and for producing electric power to drive an electric load carried on a user or any desired application, the process comprising:
generating hydrogen on demand by supplying an amount of water to hydrolyse magnesium hydride powder disposed in a reactor vessel via exothermic MgH2 hydrolysis reaction pathway;
cooling down the temperature of the hydrogen gas produced by passing the hydrogen gas through a cooling coil disposed in a water storage vessel, condensing water vapour from the hydrogen gas, and purifying the hydrogen gas by passing the hydrogen gas through a purifying filter, before supplying the hydrogen gas to a high energy density fuel cell apparatus and system;
rupturing the water discharge line at a predetermined pressure range, with the water discharge line connected to the reactor vessel;
closing the water discharge line with a check valve, so as to maintain leak-proof inside the reaction vessel, and shutting down the reactor vessel in a non-recoverable fail-safe mode when the high energy density fuel cell apparatus and system encounters a safety issue, and
having a single hydrolysis reaction zone by attaching a single steam injection point directly on the steam dispensing microporous medium,
where an array of high energy density fuel cell apparatus and system are arranged either in parallel or series in order to produce an appropriate power output level that is needed for the intended application,
where an array of the hydride-based hydrogen generators are arranged either in parallel or series in order to generate an appropriate hydrogen flow rate for the intended application,
Item 19. A process for operating a high energy density fuel cell apparatus and system with a hydride-based hydrogen generator system and for producing electric power to drive an electric load carried on a user or any desired application according to Item 18, the process comprising:
generating hydrogen on demand by supplying an amount of water to hydrolyse magnesium hydride powder disposed in a reactor vessel via exothermic MgH2 hydrolysis reaction pathway;
cooling down a temperature of the hydrogen gas produced by passing the hydrogen gas through a cooling coil disposed in a water storage vessel, condensing water vapour from the hydrogen gas, and purifying the hydrogen gas by passing the hydrogen gas through a purifying filter, before supplying the hydrogen gas to a high energy density fuel cell apparatus and system;
rupturing the water discharge line at a predetermined pressure range, with the water discharge line connected to the reactor vessel;
closing the water discharge line with a check valve, so as to maintain leak-proof inside the reaction vessel, and shutting down the reactor vessel in a non-recoverable fail-safe mode when the high energy density fuel cell apparatus and system encounters a safety issue, and
having multiple hydrolysis reaction zones by attaching multiple steam injection points directly on the steam dispensing microporous medium and physically separating each individual hydrolysis reaction zones with a physical separator in order to further improve the hydrogen gas generation rate,
where an array of high energy density fuel cell apparatus and system are arranged either in parallel or series in order to produce an appropriate power output level that is needed for the intended application,
where an array of the hydride-based hydrogen generators are arranged either in parallel or series in order to generate an appropriate hydrogen flow rate for the intended application,
In summary, the present application describes an improved power solution concept that is based on a high energy density fuel cell apparatus and system 100 and a hydride-based hydrogen generator 3 in order to produce the electrical energy needed for various applications without compromising the scalability. Conventional battery technologies have limited gravimetric energy storage values and hence limited operational time for any kind of desired application. The disclosed high energy density fuel cell apparatus and system and hydride-based hydrogen generator have a much higher gravimetric energy density value due to (i) use of a fuel cell that creates electrical energy from the electrochemical reactions of hydrogen and oxygen with high electrical efficiency and (ii) a high energy density hydride material as the source of hydrogen compared to conventional battery modules. These new advancements significantly extend the operational times of the intended applications compared to battery technologies. Furthermore, the disclosed application introduces multiple hydrolysis reaction zone concept for the exothermic MgH2 hydrolysis reaction pathway to further improve the hydrogen generation rate within the same vessel. Since high energy density fuel cell apparatus and system and the hydride-based hydrogen generator are highly scalable, the proposed concept can be used across multiple platforms without compromising the efficiency and scalability features. Finally, the fuel cell system provides several safety features to improve its safe operation.
Although the above description contains much specificity, this should not be construed as limiting the scope of the embodiments but merely providing illustration of the foreseeable embodiments. The above-stated advantages of the embodiments should not be construed especially as limiting the scope of the embodiments but merely to explain possible achievements if the described embodiments are put into practice. Thus, the scope of the embodiments should be determined by the claims and their equivalents, rather than by the examples given.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10201900953U | Feb 2019 | SG | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/SG2020/050042 | 1/30/2020 | WO | 00 |
