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Advanced Hydrogen
Storage Material
Figure 1: Structural view of the MgH2
unit cell, showing the octahedral
arrangement of Hydrogen atoms
around the Mg metal centre.
HYMOSSES
State of the art and background
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
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
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
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.
Objectives
96
on
the
hydrogen
economy,
process.
Carbon
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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,
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
state-of-the-ar t know-how of the diverse
of prime importance to investigate the feasibility
technologies involved. The HYMOSSES project
of using different types of CNT and CNF as
consists of 6 work packages covering areas of
compact media for hydrogen storage.
synthesis and production of storage materials,
The characterization and testing of these materials
characterization and testing, prototyping of storage
are a major concern of the consor tium in
devices, and the life cycle assessment of the
assessing their suitability as storage media. Other
integrated system
very important issues are the assessment of
purity ranges for hydrogen and the need to
Progress to date
investigate the effect of impurities on the
The project started in November 2002, and no
functionality of the storage materials.
data is available for reporting at this stage, but
Development and testing of prototype storage
the following is a brief outline of the scheduled
vessels are essential steps to demonstrate the
activities and goals to be achieved.
viability of hydrogen fuel in emerging technologies,
Synthesis and production of storage materials
such as Fuel Cells and Distributed Power
will target Metal Hydrides (MH), Carbon Nanotubes
Generation systems. The prototype vessels are
(CNT), and Carbon Nanofibers (CNF). For Metal
intended for UPS device applications and
hydrides, the focus will be on investigating and
miniaturized systems.
improving the hydrogen storage properties of
Life Cycle Analysis, integrating both economic
Magnesium (Mg) and Mg-based alloys, and in
and eco-design tools, will assess the economic
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
innovative aspects to be addressed are directly
and barriers for a sustainable hydrogen economy.
related to the production methods of these
Currently, the HYMOSSES consortium is closely
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
which will pave the way to fabricate Mg-alloys
a mutual cluster agreement.
and composites with unique and highly effective
INFORMATION
References: ENK6-CT-2002-00653
Programme:
FP5 - Energy, Environment and
Sustainable Development
Title:
Advanced Hydrogen Storage Material
(HYMOSSES)
Duration: 36 months
Partners:
- Universitaet Stuttgart (D)
- Electrovac Fabrikation elektrotechnischer
Spezialartikel (A)
- Consejo Superior de Investigaciones
Cientificas (E)
- Mechatronic Systemtechnik (A)
- Kungliga Tekniska Hoegskolan (S)
- Centre National de la Recherche
Scientifique (F)
- Società Italiana Acetilene and Derivati (I)
- DaimlerChrysler (D)
- Plansee Aktiengesellschaft (A)
- Université de Poitiers (F)
Contact point:
Ernst Hammel
Tel: +43-2243-450-408
[email protected]
EC Scientific Officer:
Joaquin Martin Bermejo
Tel: +32-2-2958332
Fax: +32-2-2964288
[email protected]
Status: Ongoing
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