For the time being, the energy transition, particularly in the automobile and transport sectors, is essentially based on lithium-ion battery technology. A technology which improves year after year but which retains some disadvantages compared to fossil fuels.
“Topping up” electricity can take up to several hours, the total capacity is limited, and changes depending on the outside 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 road accidents.
Why turning hydrogen into powder is a game changer
Hydrogen has long been presented as an advantageous alternative to fossil fuels. If we focus on the user experience, on paper, hydrogen can be used much like gasoline or diesel. While delivering a much higher energy density than fossil fuels or electricity stored in a Lithium-ion battery.
However, as you will have noticed, hydrogen cars are not yet very common. It must be said that technology also has its share of challenges to solve. For the time being, 90% of hydrogen is extracted from fossil fuel deposits, also at great energy cost, which is therefore not ideal when it is urgent to reduce greenhouse gas emissions Greenhouse.
Hydrogen can of course also be produced by separating water molecules. But the process is still very energy inefficient. In concrete terms, this means enormous energy losses, in order to store relatively little hydrogen in the end. And the problems don’t 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 causing a lot of damage. Storing hydrogen safely and inexpensively is therefore also one of the issues that determines the advent of this type of vehicle on the market. For the time being research had mainly concentrated on creating expensive compartmentalized 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: turning hydrogen into powder by exploiting principles of chemical mechanics. The idea here is to trigger reactions using mechanical forces rather than heat, light or electrical potential differences.
This makes it possible to mobilize much less energy. To transform their hydrogen into powder, the researchers inserted the gas into a cylindrical chamber containing steel balls and boron nitride known for its absorption capacities. The rotation of the chamber transforms the steel balls into pestles. By crushing the boron nitride, the hydrogen is gradually trapped 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. Several gases are present in this oil, so to separate and purify them, they cool all these gases until they liquefy, then heat the whole thing. The gases evaporate at different temperatures, and that’s how they separate them”.
In comparison, the researchers’ mechanical-chemical method only needs 10% of the energy currently used to produce this gas. Or a few tens of cents for several tens of hours of “spraying”. For the time being, 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 the boron nitride emptied of its hydrogen, ad infinitum.
The fact remains that even if these advances seem promising, for the time being, hydrogen has little chance in the short-medium term of appearing as a real alternative to electric cars. The charging and battery vehicle ecosystem is simply already comparatively too advanced. Hydrogen could nevertheless, thanks to this kind of progress, eventually find a use in sectors such as the transport of goods, aviation and short or long distance public transport (trains, buses, etc.).