The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM in Dresden has created a hydrogen storage paste. The institute refers to the substance as “power paste.”
Researchers believe that their paste has a high energy density and is ideal for all types of vehicles, from electric scooters to automobiles. According to Fraunhofer IFAM, the solid magnesium hydride-based power paste should enable the chemical storage and release of hydrogen at room temperature and ambient pressure. Due to the fact that the power paste decomposes at approximately 250 degrees Celsius, there are no concerns if, for instance, a paste-coated scooter is left in the summer sun for hours.
The only raw material for the storage paste is powdered magnesium, a very common metal. This reacts with hydrogen at 350 degrees Celsius and five to six times the atmospheric pressure to generate magnesium hydride. Ester and metal salt are subsequently used to generate the power paste.
In fuel cell automobiles and buses, the power paste replaces the cylindrical pressure tank. In circumstances where it would be challenging to build a pressure tank, the institute deems this option viable for hydrogen drives in smaller cars.
According to the Fraunhofer experts, the procedure of refueling is simple. Instead of travelling to a gas station, the driver of the scooter changes a cartridge and fills the water tank with tap water. Depending on the required power, the paste is squeezed from the cartridge and mixed with a precisely defined amount of water within the vehicle. This process yields hydrogen gas, which can be turned to power for the electric motor.
Half of the hydrogen in the process originates from the power paste, while the other half comes from water. According to Marcus Vogt, a scientist at Fraunhofer IFAM, the energy storage density of the power paste is significantly more than that of a 700 bar pressure tank. Compared to batteries, its energy storage density is five times greater. According to the Fraunhofer researchers, a motorist should be able to get the same or higher range with the power paste than with the same amount of gasoline.
The benefits of this type of substance are very obvious: a cartridge of the paste could theoretically be replaced anytime along a journey. Similarly, the paste might dramatically prolong the flight time of large drones, allowing them to fly for several hours rather than only 20 minutes, according to the researchers. This would allow foresters, surveyors, and high-voltage electricians to inspect forestry or electricity lines with a drone. Campers might also put the paste in a fuel cell to power a coffeemaker or toaster for a domestic application.
In addition to cartridges and canisters, the paste can be “refilled” at a filling station because it can flow and be pumped. No longer would the costly infrastructure for gaseous hydrogen at high pressure or liquid hydrogen at – 253 degrees Celsius be required.
Fraunhofer IFAM is currently constructing a production facility at the Fraunhofer Project Center for Energy Storage Systems ZESS to assess the sustainability of the paste, which includes environmental and energy balance, production, and scalability. This should be operational by the end of 2021 and produce four tons of power paste annually.
