Papers by Keyword: Hydrogen Storage

Abstract: Aluminum components production is associated with significant greenhouse gas emissions due to both raw material extraction and energy-intensive manufacturing processes. In particular, the melting phase required high thermal energy and conventional energy sources (e.g. fossil fuels, national grids...) can result in relevant environmental impacts. This study evaluates the environmental sustainability of four different energy supply systems for aluminum die casting through a comparative Life Cycle Assessment (LCA). Four scenarios were analyzed: natural gas, national grid electricity, photovoltaic (PV) electricity with battery storage, and PV-powered hydrogen production with metal-hydride storage. A cradle-to-gate approach was adopted, including energy production, storage, raw materials extraction, tool manufacturing, casting operations and finishing. The environmental impacts were modelled using SimaPro, and Global Warming Potential (GWP) was calculated according to the Intergovernmental Panel on Climate Change (IPCC) methodology. The results show that renewable-based solutions represent the most sustainable alternatives, with impact reductions up to 62% compared with traditional approaches. PV electricity with battery storage achieves the lowest unitary impacts (0.15 kg CO₂ eq/kWh). Hydrogen produced from PV electricity also provides significant reductions relative to natural gas and grid electricity and offers high operational flexibility. The metal-hydride storage system shows slightly lower impacts than battery storage, due to its long service life and minimal hydrogen losses. These results highlight the potential of renewable energy and green hydrogen as alternative energy carriers for industrial production.

Abstract: Hydrogen is a clean and sustainable energy source that has the potential to significantly lower carbon emissions worldwide and facilitate the switch to renewable energy sources. Meanwhile, one of the biggest obstacles to its broad use, is still sufficient hydrogen storage. This article provides a broad overview of hydrogen storage, tracing its historical development, exploring its diverse applications, examining technological advancements, addressing existing limitations, recent progress in reducing costs, and discussing the current state of the art in storage technologies, along with future directions for improvements in all forms of hydrogen storage methods. Therefore, this review highlights recent breakthroughs in hydrogen storage techniques, advances in cost reduction, and offers a step by step guide to designing next-generation functional hydrogen storage materials for improved performance, which are essential for both developed and developing hydrogen economies in cost reduction and better performance for hydrogen storage materials.

Abstract: The transition to hydrogen-based energy systems presents a critical need for materials capable of withstanding the harsh conditions of hydrogen storage. Our project addresses this challenge by developing a multilayer steel designed specifically for hydrogen environments. This material combines austenitic steel, known for its resistance to hydrogen embrittlement, with carbon steel, which provides strength and cost efficiency. Hydrogen embrittlement poses a well-known issue in the storage and transport of hydrogen, often degrading various metals. Although many stainless steels provide superior resistance, its high-cost limits widespread application. Our solution involves a multilayer approach, where austenitic layer serves as the primary barrier against hydrogen-induced degradation, and the carbon steel layer ensures the material’s structural strength under high pressure. The manufacturing process involves hot roll bonding, where the surfaces of the two materials are cleaned of oxides, welded together, heated up to 1200 °C, and then hot rolled to form a strong bond. This method not only strengthens the material but also makes it a potential solution for large-scale hydrogen storage applications.

Abstract: As green technology becomes a greater focus in our society, alternative energy like hydrogen fuel begins to have significance. Current technology has allowed the use of hydrogen as a fuel in fuel cells. However, a more efficient and safer means of storage would make hydrogen fuel more practical. Investigations on two-dimensional systems have already shown them to be potentially viable hydrogen storage devices. This study investigated one such 2-D system, a planar hexagonal aluminene decorated with titanium using density functional theory. Three possible adsorption sites for Ti atoms were chosen on aluminene: top, bridge, and hollow. This study showed that the Ti atom can be adsorbed at distances of 2.25 Å, 1.99 Å, and 0.00295 Å with binding energies of-2.356 eV, -4.219 eV, and-6.084 eV at the top, bridge, and hollow site, respectively. The density of states showed the Ti-decorated aluminene to be non-magnetic when the Ti atom was adsorbed at the top and bridge sites while adsorption at the hollow site resulted in a magnetic material. The charge density difference also showed chemisorption between the Ti and Al atoms which was consistent with the binding energies and the density of states. The hydrogen molecule was adsorbed on to the decoration at the top and hollow sites with binding energies of-1.41 eV and-0.494 eV, respectively. The H₂ molecule dissociated at the top site with a dissociation barrier of 0.0266 eV and an imaginary frequency of 976.99 cm^-1 in the vibrational spectrum. The results of the study showed that Ti-decorated aluminene can be a potential hydrogen storage material.

Abstract: Complex metal hydrides are one of the most effective hydrogen storage materials due to their unique property to absorb and desorb hydrogen with the hydrogen storage capacity of about 5-7 wt%. In this study, lithium aluminium hydride (LiAlH₄) was coated on glass substrate using dip coating method. The coating conditions investigated were LiAlH₄ concentrations of 6 g/l, 10 g/l and 20 g/l and post-annealing time from 0 to 60 min. Phase and grain size of the deposited LiAlH₄ were analyzed using X-ray powder diffraction (XRD). Scanning electron microscope (SEM) was used for surface morphology analysis. The hydrogen storage capacity of the deposited thin films was analyzed using thermogravimetric analysis (TGA). The experimental results revealed that the phase of the deposited LiAlH₄ thin films on glass substrate were mixed with lithium aluminium hydroxide hydrate (LiAl₂(OH)₇·2H₂O) and lithium hexahydroaluminate (Li₃AlH₆). The intensity of the LiAl₂(OH)₇·2H₂O and LiAlH₄ peaks tends to decrease with increasing LiAlH₄ concentration and post-annealing time while the intensity of the Li₃AlH₆ peaks increased with increasing LiAlH₄ concentration and post-annealing time. The grain size was decreased with increasing LiAlH₄ concentration and post-annealing time. The smaller grain size the better the hydrogen storage capacity. The hydrogen storage capacity of the deposited LiAlH₄ thin film was increased from 0.124 wt % using LiAlH₄ concentration of 6 g/l without post-annealing to 1.675 wt % using LiAlH₄ concentration of 20 g/l with 60 min post-annealing time.

Abstract: Hydrogen energy has great potential to become one of the clean energies of the future. The current use of hydrogen gas as an energy source still has problems, namely in the distribution and storage system. One solution to overcome these problems is to use the adsorption method. Zeolite material is considered to be a good material to be used as a storage medium for hydrogen gas. Experimental research generally still requires a fairly high cost. Therefore, we need another method that can support it. In this research, the author used the Molecular Dynamics Simulation method. The variation of temperature used in this simulation is 77, 100, 150, 195, 273, and 293 K with a variation of pressure at each temperature is 1, 2, 4, 6, 8, and 10 bar. Our simulation results are then compared with the results of experimental research conducted by other researchers. At low pressure and high temperature, the results of our simulation are close to the results of experimental research. But at high pressure and low temperature, the results of our simulation are significantly different from the results of experimental research.

Abstract: A physical model studying the diffusion of interstitial atoms has been used in the study of hydrogen redistribution, in order to predict the risk of hydrogen damage in a range of manufacturing processes. In this work, conditions representative of hydrogen storage and some scenarios in the nuclear or chemical industries are considered. A singular advantage of this model is that, contrary to some simplified commercial and academic models, it contemplates diffusion in its most comprehensive description, i.e., with the driving force for atom diffusion being the gradient in chemical activation instead of simply considering it occurs down a composition gradient. Because the model also incorporates thermal history, microstructure, matrix solubility, multiple trapping distributions, interaction with the atmosphere and others, it is ideally suited to study real industrial applications. In this work, several simulations of hydrogen permeation are considered. Hydrogen permeation in industrial applications may introduce damage within the metal structure, leading to delayed failure. In the cases studied hydrogen is transported through a metal wall separating one volume with high hydrogen pressure and/or high temperature from another volume with low hydrogen pressure and temperature. By using such comprehensive physical model, it is possible to study the effects of hydrogen pressure and temperature gradient, wall thickness, metal microstructure and trap distribution on the flux across the wall and on the accumulation of hydrogen within the metal. Furthermore, it makes possible to estimate the embrittlement risk and when necessary the time to fracture. Keywords: hydrogen, steel, permeation, physical model, hydrogen storage, nuclear industry

Abstract: Hydrogen storage in its solid state is one of the main challenges for mobile and stationary applications. Some metal hydrides are potential candidates for energy storage. This is an experimental research, which represents a contribution to the study of Hydrogen storage in its solid state, by studying the influence of the proportional substitution of V for Zr in the stoichiometric ratio Zr_2-XV_XFe (X=0.0, 0.1 y 0.2). Results indicate that the synthesis process generates a multi-phase type microstructure, and the absorption and desorption kinetic is less than 5 minutes at room temperature, in line with the parameters established by the United States Department of Energy; however, it is clear that the desorption capacity decreases.

Abstract: A holistic approach is required for the development of materials and systems for hydrogen storage, embracing all the different steps involved in a successful advance of the technology. The several engineering solutions presented in this work try to address the technical challenges in synthesis and application of solid-state hydrogen storage materials, mainly metal hydride based compounds. Moving from the synthesis of samples in lab-scale to the production of industrial sized batches a novel process development is required, including safety approaches (for hazardous powders), and methods to prevent the contamination of sensitive chemicals. The reduction of overall costs has to be addressed as well, considering new sources for raw materials and more cost-efficient catalysts. The properties of the material itself influence the performances of the hydride in a pilot storage tank, but the characteristics of the system itself are crucial to investigate the reaction limiting steps and overcome hindrances. For this, critical experiments using test tanks are needed, learning how to avoid issues as material segregation or temperature gradients, and optimizing the design in the aspects of geometry, hull material, and test station facilities. The following step is a useful integration of the hydrogen storage system into real applications, with other components like fuel cells or hydrogen generators: these challenging scenarios provide insights to design new experiments and allow stimulating demonstrations.

Abstract: Activated carbon has been successfully prepared from coconut shell charcoal using novel dry mechano-chemical activation with KOH and planetary ball mill. The combination of chemical activation and mechanical activation on coconut shell charcoal is found to increase its micopore volume and surface size. These increase yielded to a high adsorption capacity which was measured at 298 K and 268 K found to be 0.6 wt. % for activated carbon. The adsorption experiments were conducted using constant-volume-variable-pressure (CVVP) test. Adsorption parameters were calculated using adsorption isotherm models: Langmuir and Dubini-Asthakov models and were found in good agreement for type II adsorption phenomenon. It is also found that the adsorption capacity of activated carbon was suitable for hydrogen storage application.