Unusual properties of superconcentrated electrolyte ーQuick charge of lithium-ion batteries-


With growing public concern about environmental and energy issues, considerable effort has been devoted to the development of advanced lithium-ion batteries with high-voltage and fast-charging characters. Although lithium-ion batteries have evolved since its first commercialization in 1991, it is almost exclusively due to the development of high-performance electrode materials. In contrast, there has been little advance in electrolyte materials during the past two decades, and an electrolyte should be a key to the next great breakthrough in advanced lithium-ion batteries.
Assistant Professor Yuki Yamada and Professor Atsuo Yamada at the University of Tokyo, Graduate School of Engineering, Department of Chemical System Engineering, Dr. Keitaro Sodeyama at Kyoto University, and Dr. Yoshitaka Tateyama at National Institute of Materials Science have developed a new electrolyte for fast-charging and high-voltage lithium-ion batteries. The new electrolyte is an organic solution containing a superhigh concentration of lithium ion. The group has discovered unusual stability and fast reaction kinetics in the superconcentrated electrolyte, which far exceeds currently used commercial electrolyte. The group have revealed the origin of the peculiar properties by molecular dynamics simulations with K computer at RIKEN. The new electrolyte will open up a way to advanced lithium-ion batteries that can deliver as high voltage as 5 V and be charged for a third of time, which contribute to the widespread dissemination of electric vehicles and smart grids to realize energy-saving society.