In the face of uncertainty over global lithium supply, alternative battery chemistries are becoming an increasingly crucial need in this sector with a increased demand from electric vehicle manufacturers. One of the candidate materials that arouses the most interest in the scientific world is sodium. A team of Russian researchers of Skoltech and the Lomonosov State University of Moscow has developed an innovative cell based on this material, which offers 15% higher energy density to that of lithium batteries and which is also resistant to low temperatures.
Sodium is a material that is obtained from the oceans or from the earth’s crust and is therefore cheap, abundant and sustainable, making it a great candidate for large-scale energy storage. Is he sixth most abundant element on earth: It is unlimited and sustainable since it is harvested, not extracted. However, the sodium batteries They do not have as much energy as lithium batteries and they also cause degradation problems when charging and discharging.
In this stage, sodium ion batteries are gaining attention as a sustainable alternative to lithium-ion batteries because they work in a very similar way: the ions travel between the electrodes through a liquid electrolyte. When it is in the process of discharging, the ions are released from the anode and travel to the cathode. When the battery is connected to a charger, the opposite occurs and the battery recharges. The new research focuses on the chemical composition of the cathode or negative electrode.
The new research, from scientists at Skoltech and Lomonosov Moscow State University, focuses on the cathode. To do this, they have developed a novel material that promises to increase the energy density of the cell. It is a bitSodium Vanadium Phosphate Fluoride Compound lvo. These components are also being explored by other teams of researchers. In this case, by carefully mapping out how atoms are organized within that dust, scientists say they have taken a big step forward.
“Both our new material and the one that the industry has recently implemented are called sodium phosphate fluoride and vanadium are made from atoms of the same elements,” explains Stanislav Fedotov of Skoltech, in the research that has been published in the journal Nature Communications. “What makes them different is how those atoms are arranged and in what proportion they are contained in the compound.”
The team implemented this material in the cathode in a button-type sodium ion cell and put it to the test. She discovered that she offered a increase in energy density of up to 15% compared to current designs. In addition, this new material also allows sodium ion batteries work in colder climates.
“The increased energy storage capacity is just one of the advantages of this material,” says Fedotov. “It also allows the cathode to work at lower ambient temperatures, which is particularly relevant in places like Russia.” Now, the team says they need to expand research on these types of materials so that future batteries can be used in heavy electric vehicles, such as buses and trucks.