37 research outputs found
Hydrogen storage behavior of magnesium catalyzed by nickel-graphene nanocomposites
In present study nanocomposites of Graphene Like Material (GLM) and nickel containing 5–60 wt % Ni were prepared by a co-reduction of graphite oxide and Ni2+ ions. These nanocomposites served as effective catalysts of hydrogenation-dehydrogenation of magnesium based materials and showed a high stability on cycling. Composites of magnesium hydride with Ni/GLM were prepared by high-energy ball milling in hydrogen. The microstructures and phase compositions of the studied materials were characterized by XRD, SEM and TEM showing that Ni nanoparticles have size of 2–5 nm and are uniformly distributed in the composites. The kinetic curves of hydrogen absorption and desorption by the composites were measured using a Sievert's type laboratory setup and were analyzed using the Avraami – Erofeev approach
Hydrogen absorption study of high-energy reactive ball milled Mg composites with palladium additives
Hydrogenation behaviour, structure, morphology and dehydrogenation/re-hydrogenation performances of Mg–Pd nanocomposites prepared by high-energy reactive ball milling in H2 (HRBM) of Mg in the presence of amorphous and crystalline Pd black (0.1–5 wt.%) were studied. Improvements of hydrogenation kinetics during HRBM were observed only for the materials prepared using crystalline Pd black. The obtained nanocomposites were characterised by modest improvements in their dehydrogenation and re-hydrogenation performances associated with the formation of Mg–Pd intermetallides.Web of Scienc
Metal hydride beds-phase change materials: Dual mode thermal energy storage for medium-high temperature industrial waste heat recovery
Heat storage systems based on two-tank thermochemical heat storage are gaining
momentum for their utilization in solar power plants or industrial waste heat recovery since
they can e ciently store heat for future usage. However, their performance is generally limited
by reactor configuration, design, and optimization on the one hand and most importantly on the
selection of appropriate thermochemical materials. Metal hydrides, although at the early stage of
research and development (in heat storage applications), can o er several advantages over other
thermochemical materials (salt hydrates, metal hydroxides, oxide, and carbonates) such as high
energy storage density and power density. This study presents a system that combines latent heat
and thermochemical heat storage based on two-tank metal hydrides. The systems consist of two
metal hydrides tanks coupled and equipped with a phase change material (PCM) jacket
Research and development of hydrogen carrier based solutions for hydrogen compression and storage
Industrial and public interest in hydrogen technologies has risen strongly recently, as hydrogen is
the ideal means for medium to long term energy storage, transport and usage in combination with
renewable and green energy supply. In a future energy system, the production, storage and usage of
green hydrogen is a key technology. Hydrogen is and will in future be even more used for industrial
production processes as a reduction agent or for the production of synthetic hydrocarbons,
especially in the chemical industry and in refineries. Under certain conditions material based
systems for hydrogen storage and compression offer advantages over the classical systems based on
gaseous or liquid hydrogen. This includes in particular lower maintenance costs, higher reliability
and safety. Hydrogen storage is possible at pressures and temperatures much closer to ambient
conditions. Hydrogen compression is possible without any moving parts and only by using waste
heat. In this paper, we summarize the newest developments of hydrogen carriers for storage and
compression and in addition, give an overview of the different research activities in this field
Magnesium- and intermetallic alloys-based hydrides for energy storage: Modelling, synthesis and properties
Hydrides based on magnesium and intermetallic compounds provide a viable solution to the challenge of energy storage from renewable sources, thanks to their ability to absorb and desorb hydrogen in a reversible way with a proper tuning of pressure and temperature conditions. Therefore, they are expected to play an important role in the clean energy transition and in the deployment of hydrogen as an efficient energy vector. This review, by experts of Task 40 'Energy Storage and Conversion based on Hydrogen' of the Hydrogen Technology Collaboration Programme of the International Energy Agency, reports on the latest activities of the working group 'Magnesium- and Intermetallic alloys-based Hydrides for Energy Storage'
Control strategy of a fuel-cell power module for electric forklift
Fuel cell-battery hybrid systems for the powertrain, which have the advantage of emissionfree power generation and adapt to material transport and emission reduction, are
investigated. Based on the characteristics of the fuel cell system and the characteristics of
the electric forklift truck powertrain system, this work defines the design principle of the
control strategy to improve overall performance and economy. A simulation platform for
fuel cell and electric vehicles has been established. The optimal performance of the fuel
cell stack and the battery capacity were defined for the specific application. An energy
control strategy was defined for different operating cycles and operating conditions. Model
validation involved comparing simulation results with experimental data obtained during
VDI60 test protocol. The main parameters that influence the forklift performance were
defined and evaluated, such as energy loss, fuel cell operating conditions and different
battery charging cycles. The optimal size of the fuel cell stack of 11 kW and the battery of 10
Ah was determined for the specific load profile with the proposed control strategy. The
results obtained in this work forms the basis for an in-depth study of the energy management of fuel cell battery drive trains for forklift trucks
The use of metal hydrides in fuel cell applications
This paper reviews state-of-the-art developments in hydrogen energy systems which integrate fuel cells with metal hydride-based hydrogen storage. The 187 reference papers included in this review provide an overview of all major publications in the field, as well as recent work by several of the authors of the review. The review contains four parts. The first part gives an overview of the existing types of fuel cells and outlines the potential of using metal hydride stores as a source of hydrogen fuel. The second part of the review considers the suitability and optimisation of different metal hydrides based on their energy efficient thermal integration with fuel cells. The performances of metal hydrides are considered from the viewpoint of the reversible heat driven interaction of the metal hydrides with gaseous H2. Efficiencies of hydrogen and heat exchange in hydrogen stores to control H2 charge/discharge flow rates are the focus of the third section of the review and are considered together with metal hydride-fuel cell system integration issues and the corresponding engineering solutions. Finally, the last section of the review describes specific hydrogen-fuelled systems presented in the available reference data.IS
A review on crucibles for induction melting of titanium alloys
This review highlights the state of art progress in crucible designs which have been identified as showing potential for induction melting three groups of titanium alloys based on the systems; Ti–Al, Ti–Ni, as well as multicomponent Ti-based hydrogen storage alloys. Several important parameters for crucible design, including; crucible-melt interactions, thermodynamic stability, and, thermal shock resistance of different crucibles will be discussed. Based on the findings of the review, the selection criteria for identifying crucibles for melting titanium alloys were outlined and several specific promising solutions were suggested
Metal hydride hydrogen storage tank for fuel cell utility vehicles
The “low-temperature” intermetallic hydrides with hydrogen storage capacities below 2 wt% can provide compact H2 storage simultaneously serving as a ballast. Thus, their low weight capacity, which is usually considered as a major disadvantage to their use in vehicular H2 storage applications, is an advantage for the heavy duty utility vehicles. Here, we present new engineering solutions of a MH hydrogen storage tank for fuel cell utility vehicles which combines compactness, adjustable high weight, as well as good dynamics of hydrogen charge/discharge. The tank is an assembly of several MH cassettes each comprising several MH containers made of stainless steel tube with embedded (pressed-in) perforated copper fins and filled with a powder of a composite MH material which contains AB2- and AB5-type hydride forming alloys and expanded natural graphite. The assembly of the MH containers staggered together with heating/cooling tubes in the cassette is encased in molten lead followed by the solidification of the latter. The tank can provide >2 h long H2 supply to the fuel cell stack operated at 11 kWe (H2 flow rate of 120 NL/min). The refuelling time of the MH tank (T = 15–20 °C, P(H2) = 100–150 bar) is about 15–20 min