Scientific cooperation: new accumulator technology
News, 08 June 2020
A scientific group from the University “Dubna” in cooperation with scientists of the Joint Institute for Nuclear Research, Moscow Institute of Physics and Technology, as well as the National Research, Project and Technology Institute of Electric Coal Products (NIIEI, Electrougli, Moscow region), has developed a laboratory technology to produce lithium-ion batteries with an increased specific energy. The technology is based on the use of carbon nanotubes as conductive additives in the positive electrode of the battery.
The acquired unique scientific results allowed scientists to create a prototype of the lithium-ion accumulator with the specific energy of 150 W*h per kilogram of the battery. It is at least 20% higher than the market-average specific energy of commercial lithium-iron-phosphate batteries. At the same time, scientists believe that the further optimization of the battery’s structure will allow increasing of the specific energy up to 180 W*h/kg.
Work on the creation of electrode coatings and on the study of their electrochemical properties as well were carried out in the laboratory of the Engineering Center of Dubna University. The unique neutron reflectometer was used to study the structural properties of electrode coatings. The reflectometer was installed in the experimental hall of the IBR-2 research reactor (the Laboratory of Neutron Physics JINR).
Researchers from the University “Dubna” in their study used carbon nanotubes as conducting additives. They are tread-like structures with a diameter of about 1 nm and a length of more than 100 µm. The introduction of such thread-like structures into the electrode structures allowed creating mechanically strong electrodes with record-high capacity.
Lithium-iron-phosphate (LiFePO4) was used as an active material of the positive electrode. The choice was dictated by the fact that such a material has high electrochemical and thermal stability and is used in industry to produce lithium-ion batteries with the high electrochemical capacity. At the same time, the specific energy of such batteries is 90-120 W*h per kilogram of the battery on average.
Today, lithium-ion batteries are the most used energy accumulators as parts of various devices: from mobile phones to electric vehicles and stationary energy storage systems. It is achieved thanks to the record high value of the specific energy of lithium-ion accumulators compared to other commercial electrochemical batteries.