Increasing exploitable biomass for new sodium batteries
(sustainabilityenvironment.com) – What if the new generation of rechargeable batteries were made using poisonous herbs and weeds? The experiment is conducted by a group of Russian researchers from Lomonosov Moscow State University and Skoltech. Scientists used a toxic plant widespread in the country to create high-quality anodic material for sodium batteries.
We speak of the Heracleum Sosnowski, also called giant hogweed, species resembling the distant dill and originally imported in central Russia from the Caucasus as an experimental forage crop.
The plant is invasive and the situation quickly got out of hand, to the point that according to Skoltech researchers, today threatens to spread throughout the European part of the country by the middle of the 21st century. Bringing with it a problem for both human security and biodiversity.
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Unlike its distant cousins, the Heracleum Sosnowski is extremely poisonous. Combined with sunlight, it can cause severe skin inflammation, such as requiring hospitalization. Not only. The plant tends to easily form dense stands and, because of its size, prevents the sun from reaching the vegetation below.
The Russian team wanted to turn the problem into an asset. “We thought, it would be fun to take something as ugly and questionable as hogweed and get something useful out of it,” said co-author Zoya Bobyleva. “The advantage of hard carbon-based materials used in sodium battery anodes is that you can make them from biomass from virtually any source. No one has ever considered hogweed before. But it turned out quite good“.
First important results
The hard carbon produced from the poisonous plant showed a coulombic efficiency of 87%, equal value with the best results reported for hard carbon synthesized from other raw materials. This data shows the ability of materials to store energy without wasting it in irreversible secondary processes that actually damage the battery. As for the storage capacity, at about 260 mAh/g, the material is not yet up to the best products (about 300 mAh/g), but it offers a great start.
“The specimens collected in the summer – explains Bobyleva – proved to be better in terms of coulombic efficiency of the final product, which is the feature that we highlighted in this study, because it tends to be the weak point of hard carbon anodes. As for energy storage capacity, there are ways we can probably improve it”. The search results appeared in Batteries.