Advanced Hydrogen
Figure 1: Structural view of the MgH2
Storage Material
unit cell, showing the octahedral
arrangement of Hydrogen atoms
around the Mg metal centre.
State of the art and background
HYMOSSES To meet the environmental objectives set by the of the hydrogen economy, the automotive industry
Kyoto protocol and to achieve sustainable growth is considering the feasibility and economic
based on the hydrogen economy, the viability of the different options of hydrogen
transportation and power generation sectors storage. For solid hydrogen storage, the industry
are in the process of switching to alternative fuels recommends a storage capacity in the range of
Objectives derived from renewable resources. Hydrogen is 4.5-6% by weight and which can deliver 250
considered a key fuel and the problems related scm3/s at pressure of 5 bar at temperatures 80-
Hydrogen is an energy carrier with great to its storage are of major concerns to further 100°C. Recent reports from The DOE, USA reveal
potential to become a major fuel for both development in these sectors. Hydrogen can be that 6 wt.% threshold of hydrogen capacity is
mobile and stationary power generation. stored in the form of gas, cryogenic liquid, or economically viable. The stochiometric compound
One major hurdle in using hydrogen on a adsorbed gas in solid materials. Due to the low MgH2 adopting the stable rutile crystal lattice
commercial scale is the lack of cost energy density per volume (12.5 MJ/m 3), would provide storage capacity of 7.66wt%,
effective, compact, and safe storage hydrogen gas is normally stored under high however, with impractical cycling kinetics (Figure
solutions. Therefore, the objective of the pressure in the range of 200-700 bars. This in 1). Recent research results showed that cycling
HYMOSSES consortium is to develop turn requires the use of specially constructed kinetics can be dramatically improved by using
advanced hydrogen storage materials with pressure vessels, which are energy consuming a distorted nano-scaled Mg structure and/or
the main focus on Metal hydrides (MHs), and expensive for large-scale applications. doping the host lattice with e.g., transition metal
Nanostrustructured Carbon Materials, and Cr yogenic hydrogen (23 K) is obtained by species, which ser ve as catalysts for the
Composite materials thereof. Other liquefaction, which is an energy intensive adsorption/desorption process. Carbon
activities involve prototyping of vessels process, and requires specially insulated vessels materials, in particular catalytically grown carbon
and tanks, fuel handling and production, fitted with appropriate fuel handling devices. nanofibers and carbon nanotubes, constitute
and conducting Life Cycle Analysis of the The main problems related to cryogenic hydrogen another important class of materials that received
techno-economic viability of the developed are boil-of f and leakage during storing and tremendous attention and speculation regarding
materials, and to assess the future handling, and safety issues. Storing hydrogen in hydrogen storage proper ties. This has been
prospects of the hydrogen economy. solid materials, which are safer and more energy initiated by published results from the
ef ficient could substantially reduce these Northeastern University, MA, USA, which showed
problems. Presently, metal hydrides and carbon a hydrogen uptake, of cer tain Graphitic
nanostructures are receiving attention because Nanofibers, of more than 60 mass %. No
of their potential to provide compact and international research group working in this area
lightweight hydrogen storage. The reversible could reproduce the claimed results. For Carbon
storage of small amounts of hydrogen (<2wt%) Nanotubes, a research group at NREL published
by certain metals and metal alloys in the form results, supported by Monte-Carlo simulations,
of hydrides is well known. Metal hydrides find showing that graphitic cylinders, when opened at
wide applications in the niche market of NiMH both ends have good absorbing capacity and
batteries for portable devices. Within the context can reversibly store hydrogen.
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Figure 2: SEM imaging of Electrovac Carbon
Nanofibers to be used in this project. The inset shows
a TEM view of a fiber exhibiting platelet structure.
Project structure
HYMOSSES is a well-balanced R&D consortium cr ystallographic features. There are however
involving par tners from both academia and mixed signals from published data about the
industr y, with the objective to develop and nanostructured carbon materials and their
demonstrate the feasibility of hydrogen storage in hydrogen storage capacity. Nonetheless due to
solids. The industrial partners are potential end their unique characteristics in terms of high
users of the expected results and the technologies surface area, low density, and chemical inertness, INFORMATION
under development. The consor tium is pan- it is conceivable that these materials will have high
European in dimension with each partner having mechanical stability and prolonged life. It is thus References: ENK6-CT-2002-00653
state-of-the-ar t know-how of the diverse of prime importance to investigate the feasibility
Programme:
technologies involved. The HYMOSSES project of using different types of CNT and CNF as FP5 - Energy, Environment and
consists of 6 work packages covering areas of compact media for hydrogen storage. Sustainable Development
synthesis and production of storage materials, The characterization and testing of these materials
Title:
characterization and testing, prototyping of storage are a major concern of the consor tium in Advanced Hydrogen Storage Material
devices, and the life cycle assessment of the assessing their suitability as storage media. Other (HYMOSSES)
integrated system very important issues are the assessment of
Duration: 36 months
purity ranges for hydrogen and the need to
Progress to date investigate the effect of impurities on the Partners:
The project started in November 2002, and no functionality of the storage materials. - Universitaet Stuttgart (D)
data is available for reporting at this stage, but Development and testing of prototype storage - Electrovac Fabrikation elektrotechnischer
Spezialartikel (A)
the following is a brief outline of the scheduled vessels are essential steps to demonstrate the
- Consejo Superior de Investigaciones
activities and goals to be achieved. viability of hydrogen fuel in emerging technologies, Cientificas (E)
Synthesis and production of storage materials such as Fuel Cells and Distributed Power - Mechatronic Systemtechnik (A)
will target Metal Hydrides (MH), Carbon Nanotubes Generation systems. The prototype vessels are - Kungliga Tekniska Hoegskolan (S)
- Centre National de la Recherche
(CNT), and Carbon Nanofibers (CNF). For Metal intended for UPS device applications and Scientifique (F)
hydrides, the focus will be on investigating and miniaturized systems. - Società Italiana Acetilene and Derivati (I)
improving the hydrogen storage properties of Life Cycle Analysis, integrating both economic - DaimlerChrysler (D)
- Plansee Aktiengesellschaft (A)
Magnesium (Mg) and Mg-based alloys, and in and eco-design tools, will assess the economic
- Université de Poitiers (F)
addition on nanostructured composites of Mg viability and environmental impact of the developed
and CNT and/or CNF respectively (Figure 2). The materials. It will also assess the market incentives Contact point:
innovative aspects to be addressed are directly and barriers for a sustainable hydrogen economy. Ernst Hammel
Tel: +43-2243-450-408
related to the production methods of these Currently, the HYMOSSES consortium is closely
hae@electrovac.com
materials using high-energy ball milling or alloying collaborating with the FUCHSIA and HYSTORY
by spin melting. These are promising methods, consortia in the area of hydrogen storage under EC Scientific Officer:
which will pave the way to fabricate Mg-alloys a mutual cluster agreement. Joaquin Martin Bermejo
Tel: +32-2-2958332
and composites with unique and highly effective Fax: +32-2-2964288
joaquin.martin-bermejo@cec.eu.int
Status: Ongoing
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