Metal Hydrides for Fuel Cell Storage

The climate crisis continues to grow as an existential threat. Establishing reliable energy resources that are renewable and zero-carbon emitting is a critical endeavour. Hydrogen has emerged one such resource due its high gravimetric density near-abundant availability. However, it suffers from low volumetric incredibly challenging store transport. metal hydride, solid-state storage method, provides viable solution the current limitations. Storage achieved through chemical absorption of hydrogen into porous alloys sublattice. But thermodynamic functionality leaves gap between ideal capacity industry requires limited reusable hydrides currently provide. This work used mathematical modelling determine optimal operating conditions for hydride in order maximise capacity. Computational fluid dynamics simulate coupled heat mass transfer occurs during process alloy. finite volume method discretise governing equations, alternating direction implicit numerical solutions proved most stable platform conduct analyses. An initial investigation grid sizing conducted node allocation. impact bed ... Read More

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This study investigates the structure of a metal hydride (MH) cartridge as hydrogen storage tank for small-scale fuel cells (FCs). is designed to be stacked and used in layers, allowing flexible capacity adjustment according demand. MH enables compact safe cell (FC) applications due its high energy density low-pressure operation. However, because desorption from an endothermic reaction, external heat supply required stable performance. To enhance both transfer efficiency usability, we propose method that utilizes waste air-cooled proton-exchange membrane (PEMFC). The proposed incorporates four cylindrical tanks require uniform transfer. Therefore, arrangements within minimize non-uniformity distribution on surface. flow exhaust air PEMFC into was analyzed using computational fluid dynamics (CFD) simulations. In addition, empirical correlation Nusselt number developed estimate coefficient. As result, it concluded utilization rate flowing 13.2%.

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Hydrogen storage device for preventing excessive pressure rise in hydrogen storage containers due to temperature changes. The device uses two types of metal hydride materials with different pressure storage capabilities inside the container. As temperature and pressure rise, hydrogen discharged from the first material with lower storage capacity can be absorbed by the second material with higher storage capacity. This prevents container pressure spikes when external temperatures rise.

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This review delves into the advancements of TiFe alloy for solid-state hydrogen storage, highlighting its structure, properties, preparation method, and storage performance. The impact composition microstructure upon kinetics were explored summarized, as well on capacity. work details synthesis methods, from induction melting to mechanical alloying, discusses strategies enhance TiFe's absorption/desorption rates cycling stability. Emphasis is placed role process control agents nanostructuring in improving performance alloy. underscores potential alloys realizing a sustainable economy outlines challenges activation conditions cost reduction, providing roadmap future research directions.

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Magnesium hydride (MgH2) is a promising solidstate hydrogen storage material due to its high capacity and low cost, but dehydrogenation temperature poor kinetic limits applications. Although catalytic modification of MgH2 has been extensively studied, existing efforts focus on optimizing transfer, with limited exploration electron transfer transport. This study investigated the enhancement transport rates during de/hydrogenation by introducing singleatom catalyst composed Ru single atoms Nb2O5 substrate. The Ru0.028@Nb2O5 reduced peak from 429 214 C, activation energies for were 53.7% 83.9%, respectively. Furthermore, 15wt%Ru0.028@Nb2O5MgH2 composite maintained 97.4% after 100 cycles. Based excellent performance theoretical calculations, it was demonstrated that electronic structure modulation enhanced capacities, synergistic effects (dominant role), multivalent Nb, oxygen vacancies resulted in remarkable activity. offers new strategy improving modulating catalysts, thereby increasing activity pyrolysis reaction materials.

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Magnesium hydride (MgH2) is a promising solidstate hydrogen storage material due to its high capacity and low cost, but dehydrogenation temperature poor kinetic limits applications. Although catalytic modification of MgH2 has been extensively studied, existing efforts focus on optimizing transfer, with limited exploration electron transfer transport. This study investigated the enhancement transport rates during de/hydrogenation by introducing singleatom catalyst composed Ru single atoms Nb2O5 substrate. The Ru0.028@Nb2O5 reduced peak from 429 214 C, activation energies for were 53.7% 83.9%, respectively. Furthermore, 15wt%Ru0.028@Nb2O5MgH2 composite maintained 97.4% after 100 cycles. Based excellent performance theoretical calculations, it was demonstrated that electronic structure modulation enhanced capacities, synergistic effects (dominant role), multivalent Nb, oxygen vacancies resulted in remarkable activity. offers new strategy improving modulating catalysts, thereby increasing activity pyrolysis reaction materials.

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TiMn- and TiCrMn-based metal hydride alloys for reversible hydrogen storage that can absorb and release hydrogen at moderate temperatures and pressures. The alloys are tuned by adding modifier elements like VFe, Fe, Cu, Co, Ti, Zr, Al, Cr, La, Ni, Ce, Ho, Mo, and V to adjust properties like hydrogen uptake/release pressure, plateau slope, hysteresis, and equilibrium pressure. This enables customization for specific hydrogen storage applications like electrolysers and fuel cells. The alloys can have high hydrogen storage capacities, rapid uptake/release rates, and reduced hysteresis compared to known alloys. The tuning allows matching alloy properties to the hydrogen storage requirements of electrolysers and fuel cells.

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Lightweight, high-capacity hydrogen storage system for electric vehicles that enables quick and simple refueling. The system uses a replaceable structural component with an integrated hydrogen storage material. The storage material is a metal foam containing a hydrogen-absorbing metal hydride. The component can be swapped out like a battery pack to quickly and easily refuel the vehicle with hydrogen. The hydrogen-absorbing foam has high hydrogen density and low weight compared to pressurized tanks. The component attaches to the vehicle with a fluid connection to the fuel cell stack. The foam releases hydrogen when heated, which is fed to the fuel cell for power generation. The component design enables on-demand hydrogen refueling by replacing the depleted component.

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A hydrogen storage composite material with improved hydrogen storage performance by combining metal hydride, a hydrogen storage material, with a graphene oxide framework, a carbon-based matrix material, to replace traditional high-pressure hydrogen storage tanks. The graphene oxide framework has a very small pore size of 1-2 nm compared to previous carbon materials, allowing for better impregnation of metal hydride. This composite material has higher hydrogen storage capacity and lower cost compared to prior approaches. The composite is made by ultrasonically grinding graphene oxide in a solvent, forming a graphene oxide framework through solvothermal reaction with a linker, and then impregnating metal hydride onto the framework.

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Abstract This study investigates the thermal coupling of a 1 kW PEM fuel cell (FC) with LaNi5 metal hydride (MH) hydrogen storage system at 40C. A 1D MATLAB model solves coupled transport and reaction equations along FCs layers has been experimentally validated to confirm its polarization, consumption performance higher operating temperatures (70C), while COMSOL-based transient simulates release in MH tank, used train feedforward neural network for flow estimation. The cells stack voltage variation impacts balance between heat generated by required tank desorption Thermal energy recovery is maximized intermediate voltages, matching points production are observed up 2000 NL capacities.

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Heat generating material that can produce a large amount of excess heat when exposed to hydrogen gas at temperatures below the melting point of a secondary metal. The material contains a first metal with a high melting point (230°C or more) and a second metal with a higher melting point. At least one of the metals has high hydrogen solubility below the secondary metal's melting point. The hydride of this metal has a standard enthalpy of formation equal to or greater than CaH2. This allows the material to absorb and desorb hydrogen at lower temperatures to generate significant heat. The high hydrogen solubility and hydride properties prevent agglomeration and maintain hydrogen absorption at high temperatures.

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<title>Abstract</title> Hydrogen storage in lithium borohydride (LiBH4) with high gravimetric and volumetric hydrogen densities has attracted intensive research interest. However, the working temperatures poor reversibility due to thermodynamic stability kinetic barriers, limits its practical applications. Herein, we fabricate a unique trilayered nanostructure composed of layers graphene support, Ni nanoclusters, LiBH4 nanoparticles, through layer-by-layer assembly approach. The nanoclusters offer nucleation sites, separate nanoparticles from graphene, catalyze formation B-H bonds eliminate foaming effect. During hydrogenation, cleaves H-H B clusters, creating additional absorption sites reducing H adsorption energy B, which lowers dissociation barrier, allowing reversible approximately 12.27 wt% H2 by commencing 70 C under 100 bar H2. This finding guides design fabrication light-metal hydride nanostructures for on-board

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Hydrogen is a key energy carrier, playing vital role in sustainable systems. This review provides comparative analysis of physical, chemical, and innovative hydrogen storage methods from technical, environmental, economic perspectives. It has been identified that compressed liquefied are predominantly utilized transportation applications, while chemical transport mainly supported by liquid organic carriers (LOHC) ammonia-based Although metal hydrides nanomaterials offer high capacities, they face limitations related to cost thermal management. Furthermore, artificial intelligence (AI)- machine learning (ML)-based optimization techniques highlighted for their potential enhance efficiency improve system performance. In conclusion, systems achieve broader applicability, it recommended integrated approaches be adoptedfocusing on material development, feasibility, environmental sustainability.

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In this study, we investigate the structural, elastic, electronic, and thermodynamic properties of LaMgX2 (X = Zn, Cd, Hg) intermetallic hydrides using first-principle calculations based on density functional theory. The compounds exhibit metallic behavior with relatively high bulk moduli, suggesting good mechanical stability. parameters, such as Debye temperature entropy, were derived analyzed to evaluate their thermal Furthermore, hydrogen storage potential these was assessed, revealing favorable characteristics for reversible absorption desorption. addition, thermoelectric investigated by evaluating key indicators Seebeck coefficient, electrical conductivity, electronic contribution conductivity. These insights into energy transport further support multifunctional potential. Overall, findings highlight LaMgM2 promising candidates applications, especially in energy-efficient technologies.

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The current world is increasingly focusing on renewable energy sources with strong emphasis the economically viable use of to reduce carbon emissions and safeguard human health. Solid-state hydrogen (H2) storage materials offer a higher density compared traditional gaseous liquid methods. In this context, review evaluates recent advancements in binary, ternary, complex metal hydrides integrated 2D Ti3C2 MXene for enhancing H2 performance. This perspective highlights progress made through development active sites, created by interactions between multilayers, few-layers, internal edge sites hydrides. Specifically, selective incorporation content has significantly contributed improvements performance various Key benefits include low operating temperatures enhanced capacity observed MXene/metal hydride composites. versatility titanium multiple valence states (Ti0, Ti2+, Ti3+, Ti4+) Ti-C bonding plays crucial role optimizing absorption desorption processes. Based these promising developments, we emphasize potential solid-state interfaces fuel cell applications. Overall, MXenes represent s... Read More

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Enhancing and controlling deuterium loading reactions in metals like palladium for applications like hydrogen storage, fuel cells, and nuclear fusion. The technique involves a two-stage loading process with a barrier to increase reaction rates. In the first stage, deuterons are loaded into the metal cathode from an anode at high efficiency. Then, in the second stage, a barrier is added to obstruct isotopic fuel flow. This triggers a sudden, rapid release of hydrogen within the metal due to catastrophic desaturation of the lattice. The barrier prevents loss of the loaded cathode. The technique improves reaction rates, reduces charging times, and enables higher concentrations compared to traditional loading methods.

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Metal hydrides play a pivotal role in advancing the hydrogen economy by providing compact solution for onboard storage. However, their practical application is hindered undesirable side reactions and slow kinetics during uptake release. We present herein enhanced thermodynamics of uptake/release through infiltration lithium borohydride (LiBH4) into Mo2N-doped defective boron nitride (Mo2N-DBN) host. Density functional theory (DFT), Ab initio molecular dynamics (MD), wide array experimental data suggested that Mo2N-DBN host promotes proximity between active sites LiBH4, effectively preventing aggregation sorption processes, thereby leading to reversible storage capacity 10.80 wt % at 200 C 50 bar LiBH4@Mo2N-DBN composite with minimal loss after five hydrogenation-dehydrogenation cycles. This marked an 84% enhancement over pure LiBH4 under identical conditions represented highest reported among LiBH4-based composites date. The Mo2N prevented direct melting transitions facilitated weakening H-H bonds, which turn gave rise fast dehydrogenation (Ea = 77.44 0.02 kJ/mol). Additionally,... Read More

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Magnesium hydride (MgH2) has been recognized as a promising hydrogen storage material because of its low cost and high capacity. However, the sluggish kinetics operating temperature hindered utilization. Herein, vanadium-substituted titanium-based bimetallic MXene (Ti3-nVnC2) was prepared to boost efficiency MgH2. The incorporation 5 wt % Ti2.2V0.8C2 dramatically decreased dehydrogenation MgH2 improved cyclic stability. MgH2-5 started release at 165 C, it released 7.0 H2 in 30 min 220 C took 5.3 2 h 75 showing excellent kinetics. In addition, activation energy MgH2-added 80.81 3.29 kJ mol-1, which is lower than that most Ti-/or V-based catalyst-doped systems. Mechanism analysis reveals remarkably enhanced performance ascribed stable existence uniform distribution Ti-species (Ti0 Titanium hydride) V-species (V0 V5+), facilitated rapid absorption/desorption ensured This study offers valuable perspectives for assembly design catalysts within realm solid-state materials.

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Abstract Metal hydrides (MHs) are promising candidates for storing hydrogen at ambient conditions high volumetric energy densities. Recent developments suggest hydridebased systems can cycle and operate favorable pressures temperatures that work well with fuel cells used in stationary power applications. In this study, we present a comprehensive design cost analysis of MHbased long duration storage facilities variety end users (0 to 20 megawatts (MW) supplied over 0 100 hours), offer insights on technical targets material development operation strategies. Our findings indicate hold significant size advantage physical footprint, requiring up 65% less land than 170bar compressed gas storage. hydride be competitive 350bar systems, TiFe 0.85 Mn 0.05 achieving $0.45/kWh complex 2Mg(NH 2 ) 2.1LiH0.1KH $0.38/kWh. Extending charging times increasing operating cycles significantly reduce levelized storage, especially MHs. Key strategies further enhance the competitiveness MHs include leveraging waste heat from cells, reducing use critical minerals, MH production costs US$10/... Read More

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Integrated hydrogen energy storage and distribution system that uses thermal coupling between the electrolyzer, metal hydride storage, and fuel cell modules to improve efficiency by utilizing and reusing thermal energy. The modules are connected so that heat released during exothermic reactions can be used to supplement heating needs during endothermic reactions. This avoids wasting heat and enables more efficient overall operation. The system is coordinated by a computer that balances hydrogen storage, production, and consumption based on demands.

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