Metal Hydrides
Alane (Aluminum Trihydride)
Team discovers way to make alane a better hydrogen fuel option for vehicles.
"Alane is great because it meets all of the criteria put forth by the Department of Energy for hydrogen fuel cell vehicles for energy capacity, weight, system temperature, and cost" said Vitalij Pecharsky ... Professor of Materials Science. "Aluminum is cheap, hydrogen is abundant [... but f]or the longest time it's been considered impossible to use for vehicle applications" ..
Researchers paired the predictive advantages of computational analysis with physical experiment to tackle the applied materials challenge. Along with titanium catalyst dopants and hydrogen, theorists looked at vacancy defects, or missing aluminum, on the surface of aluminum powders and established that this combination working in concert is critical to the low-energy formation of alane. Because such defects can be produced by ball milling to break up mechanically the atomic structure of the metal, experimentalists ball-milled aluminum powders in combination with hydrogen and titanium, and they confirmed the prediction by producing AlH3, or alane. The process used significantly less pressure, only about 5,000 PSI (or 30 times less pressure), to create alane than that needed for equilibrium methods.
Ardica specializes in the production of Alane, a highly stable, extremely lightweight hydrogen powder now used by a select set of customers in industrial and military applications. The U.S. Army has been working closely with Ardica for many years to test Alane’s superior ability to power a wide range of mobile and vehicular applications. By replacing traditional batteries, Alane greatly reduces weight and extends operations while increasing the safety and efficiency of the soldiers.
The U.S. Army chose Alane because it can be stored, shipped, stocked, and accessed easily. Alane does not lose its energy potential over time and is unaffected by temperature variations. It does not require massive capital investment to develop new infrastructure, and can be recycled and regenerated"
Manganese Hydride
Scientists have discovered a new material that could hold the key to unlocking the potential of hydrogen powered vehicles.
As the world looks towards a gradual move away from dirty fuel powered cars and trucks, greener alternative technologies are being explored, such as electric battery powered vehicles.
Another ‘green’ technology with great potential is hydrogen power. However, a major obstacle has been the size, complexity, and expense of the fuel systems – until now.
An international team of researchers, led by Professor David Antonelli of Lancaster University, has discovered a new material made from manganese hydride that offers a solution. The new material would be used to make molecular sieves within fuel tanks - which store the hydrogen and work alongside fuel cells in a hydrogen powered ‘system’.
The material, called KMH-1 (Kubas Manganese Hydride-1), would enable the design of tanks that are far smaller, cheaper, more convenient and energy dense than existing hydrogen fuel technologies, and significantly out-perform battery-powered vehicles.
Professor Antonelli, Chair in Physical Chemistry at Lancaster University and who has been researching this area for more than 15 years, said: “The cost of manufacturing our material is so low, and the energy density it can store is so much higher than a lithium ion battery, that we could see hydrogen fuel cell systems that cost five times less than lithium ion batteries as well as providing a much longer range – potentially enabling journeys up to around four or five times longer between fill-ups.”
The material takes advantage of a chemical process called Kubas binding. This process enables the storage of hydrogen by distancing the hydrogen atoms within a H2 molecule and works at room temperature. This eliminates the need to split, and bind, the bonds between atoms, processes that require high energies and extremes of temperature and need complex equipment to deliver.
The KMH-1 material also absorbs and stores any excess energy so external heat and cooling is not needed. This is crucial because it means cooling and heating equipment does not need to be used in vehicles, resulting in systems with the potential to be far more efficient than existing designs.
The sieve works by absorbing hydrogen under around 120 atmospheres of pressure, which is less than a typical scuba tank. It then releases hydrogen from the tank into the fuel cell when the pressure is released.
The researchers’ experiments show that the material could enable the storage of four times as much hydrogen in the same volume as existing hydrogen fuel technologies
Magnesium hydride (MgH2) is a promising material for solid hydrogen storage due to its superior hydrogen storage capacity… Our results obtained by spin-polarized density functional theory calculations with van der Waals corrections (DFT-D3) unveiled an interesting “burst effect” during MgH2 dehydrogenation
Metal Hydrides
In general metal hydrides have been known since WWII. A product called LAVO [1] essentially turned the technology into a hydrogen battery where the unit is continuously charged (into H2) and discharged as energy is used.
"The hydrogen hydride alloy used in Lavo is based on a technology that emerged after WWII, where hydrogen molecules attach to metals such as magnesium or aluminium. Professor Kondo-Francois Aguey-Zinsou, chief scientist and executive director of Lavo and lead researcher in hydrogen technologies at UNSW, has been researching hydrides for more than 20 years. Muller says Aguey-Zinsou has 'cracked the code' with the alloy used in the Lavo storage system"
"The LAVO system uses innovative, patented metal hydride technology to store hydrogen equivalent to up to 60kWh electricity, which is enough to power an average household for approximately three days"
"@ASYNSIS
5 times the storage capacity, 1/10th the cost of Lithium batteries. #LAVO Hydrogen energy breakthrough.."
References
[1] Lavo
[2] Lavo Site