With a teaspoon of sugar: researchers solve the problem of a super battery
Lithium-sulfur batteries have an enormous capacity, but so far they have decomposed their electrodes too quickly. Australian researchers were able to solve the problem by adding sugar.
All over the world people are looking for the next “miracle battery” that can replace today’s lithium-ion solutions. Australian scientists have now come up with an unconventional method: They have integrated sugar – an organic material – into a lithium-sulfur battery. The sweet addition should solve the cardinal problem of this technology, the stability should now have been increased to over 1000 charging cycles.
The lithium-sulfur technology is particularly promising because up to five times as high charging capacities can be achieved in the laboratory. The problem: the electrodes in these batteries wear out quickly A year ago, researchers at Monash University in Australia were able to stabilize the positive sulfur electrode. A binding agent has been integrated here so that the electrode can withstand the strong expansion during charging.
Sugar prevents sulfur crust
On the other hand, the lithium negative electrode has been made unusable by sulfur impurities. Long chains of sulfur overgrown the electrode. Now the addition of sugar prevents the formation of long sulfur chains on the material. These polysulfides had overgrown the electrode like moss. The sugar was incorporated into the material of the electrode as a net-like microstructure, and prevents the formation of polysulfides there.
The test cell then retained its capacity for over 1000 cycles. “So each charge lasts longer, which extends the life of the battery,” says researcher Yingyi Huang. “And no exotic, toxic and expensive materials are required to manufacture the batteries.”
Breakthrough for trucks and drones
The technology is not yet ready for series production and the authors say that the protection of the lithium metal anode must be further improved. But the technology is particularly attractive for mobile applications. This is where the up to five times higher capacity of the technology pays off. A vehicle that has a range of 400 kilometers today would travel 2000 kilometers with the same battery size. It would also be attractive to install a smaller battery for a practical range in order to reduce the excess weight of electric vehicles. The most important point, however, is that batteries of this capacity are required to properly electrify heavy vehicles such as buses and trucks.
“In less than a decade, this technology could lead to vehicles such as electric buses and trucks that can travel from Melbourne to Sydney without charging. It could also enable innovations in delivery and agricultural drones, where light weight is paramount,” he said the lead author of the study, Professor Mainak Majumder
Those: Nature Communications