| Scientists have developed a material
that could solve hydrogen storage issues. The sponge-like substance can
store the gas in a solid cube that can be held in the hand, but production
is a long way off.
“We’ve discovered a new set of materials that will store hydrogen,”
said Professor Bill David, senior fellow at the ISIS science centre at
the UK’s Rutherford Appleton Laboratories. “We’ll have
a demo in 2008, with prototype vehicles in the next five years.”
The material is a form of lithium borohydride amide. Its chemical properties
bind hydrogen molecules closely to it, allowing them to be stored more
densely than is possible even with pure liquid hydrogen.
A solid block of the material could store 10 or 11 per cent of its own
weight as hydrogen at room temperature, and would need to be heated only
to 100ºC to release the gas.
Compressed hydrogen storage systems can achieve similar hydrogen by weight
ratios, but 7 to 8 per cent is more common. The compression process is
also expensive and requires energy.
Liquid hydrogen is a more efficient method of storage than gas but cooling
the hydrogen to about –253ºC and maintaining this temperature
requires heavy, expensive equipment as well as a cryogenic storage tank.
The ISIS material should weigh no more than an average gasoline tank and
it does not require any further equipment as there is no compression or
cooling required. It also avoids the safety factors concerning compressed
gas and refrigeration.
There are still serious issues to be addressed before the technology can
be considered viable. David and his team have so far produced only small
test samples. They are working with engineers at the Rutherford lab and
in Oxford to find methods for loading the material.
Also, the process is non-reversible. A cube of the material would be a
one-shot solution, similar to a non-rechargeable battery. Another problem
is the high cost of lithium.
But the results have been encouraging, and David is working with a US
lab and the University of Singapore to develop a similar material which
would be cheaper and reversible. It is likely to be used in laptops and
consumer electronics first.
“In 15 years we would hope to see this solution in 20 per cent of
all cars,” David said.
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