At present, energy conversion, especially in the automotive and transportation sectors, is mainly based on lithium-ion battery technology. A technology that is improving year after year, but which has some disadvantages compared to fossil fuels.
It can take up to several hours to “top up” electricity, the total capacity is limited and changes depending on the outdoor temperature or the total number of battery cycles. Not to mention the risks, such as fire outbreaks caused by the extreme reactivity of lithium during traffic accidents.
Why converting hydrogen to powder is a game changer
Hydrogen has long been presented as an advantageous alternative to fossil fuels. If we focus on the user experience, hydrogen on paper can be used much like gasoline or diesel. At the same time, it delivers a much higher energy density than fossil fuels or electricity stored in a lithium-ion battery.
But as you may have noticed, hydrogen cars are not yet very common. It must be said that technology also has its share of challenges to solve. Currently, 90% of hydrogen is extracted from fossil fuels, also with high energy costs, which is therefore not ideal when there is an urgent need to reduce greenhouse gas emissions.
Of course, hydrogen can also be produced by separating water molecules. But the process is still very energy efficient. Specifically, it means enormous energy loss, to ultimately store relatively little hydrogen. And the problems do not stop there: the hydrogen atom is so small that it can diffuse and pass through almost any material.
This gas is also known to be dangerous in the presence of oxygen – it can explode spontaneously and cause a lot of damage. Storing hydrogen safely and cheaply is therefore also one of the issues that conditions the emergence of this type of vehicles on the market. For the time being, research had mainly concentrated on creating expensive divided tanks.
The method is also interesting for extracting hydrogen at a lower cost
But researchers at Deakin University seem to have discovered both a much cheaper and much more interesting method of production and storage: to convert hydrogen into powder by utilizing the principles of chemical mechanics. The idea here is to trigger reactions using mechanical forces instead of heat, light or electrical potential differences.
This makes it possible to mobilize much less energy. To convert their hydrogen into powder, the researchers inserted the gas into a cylindrical chamber containing steel spheres and boron nitride known for its absorbency. The rotation of the chamber turns the steel balls into impact. By crushing the boron nitride, the hydrogen is gradually captured in the powder – which can then be used directly as it is.
The researchers explain: “Currently, the petrochemical industry uses a cryogenic process to separate hydrogen from crude oil. There are several gases in this oil, so to separate and purify them, they cool all these gases until they become liquid, and then heat it all up. The gases evaporate at different temperatures, and that is how they separate them ”.
By comparison, scientists’ mechanical-chemical methods need only 10% of the energy currently used to produce this gas. Or a few dozen pennies for tens of thousands of hours of “spraying”. So far, researchers are only at the beginning of the development of this separation and storage technology. Their next ambition is to show that it is possible to recycle boron nitride, which has been depleted of its hydrogen, indefinitely.
Still, although these advances seem promising, hydrogen has so far had little chance in the short to medium term to emerge as a real alternative to electric cars. The ecosystem of the charging and battery vehicle is simply already relatively advanced. Nevertheless, thanks to this kind of progress, hydrogen could eventually be used in sectors such as freight transport, aviation and short- or long-distance public transport (trains, buses, etc.).