The International Science and Technology Innovation Cooperation Project, Exploitation of industrial technology for solid lithium-sulfur battery based on composite electrolyte membrane, jointly funded by the Ministry of Science and Technology of China and the National Science and Technology Promotion Agency (JST), was officially launched at Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, on August 19th to 20th, 2019. This project will be co-conducted by professor Kiyoshi Kanamura from Tokyo Metropolitan University and Professor JIN Yongcheng from QIBEBT.

The solid-state battery is one of the most effective ways to solve the problems of leakage and burning of organic electrolyte in lithium-sulfur batteries. QIBEBT has carried out a series of studies on modified cathode materials, optimized electrolytes, modified membranes and catalytic conversion of lithium polysulfide, which has effectively improved the cycle stability of lithium-sulfur batteries. On this basis, the solid electrolyte is used instead of the organic electrolyte to further improve the performance of the lithium-sulfur battery. The solid lithium-sulfur battery with organic/inorganic composite electrolyte membrane can successfully charge and discharge at 35 °C, and the capacity after 100 cycles is maintained at ~800 mAh g-1. Furthermore, a series of flexible electrolyte membranes prepared by the “rigid and flexible” composite structure design concept can escort the smooth implementation of the project. Japanese partners have used the ion doping technology to achieve the synthesis of inorganic electrolytes with improved electrolyte interface properties at low temperatures. Combining the three-dimensional interconnected electrode structure and functional material coating layer, they improve the dissolution anode precipitation characteristics of Li ion in the anode of solid state battery.

Therefore, this cooperative project effectively brings together the research advantages of organic polymer electrolytes from Chinese side and that of inorganic solid electrolytes from Japanese side. The Advanced Interface Technology Research Group, Biomimetic and Solid State Energy Systems Research Group from QIBEBT will work together with the Tokyo Metropolitan University and Wuhan University of Technology, from basic research on scientific issues such as micro-area interface characterization and regulation mechanisms, to key technology development such as large-capacity flexible packaging battery assembly. Through cooperation, the partners are expected to solve the difficult problems currently existed in the preparation process of high-energy density and high-safety solid lithium-sulfur batteries. This will reserve technical foundations in industrialization of solid-state battery and provide manufacturing guidelines. At the same time, in the process of project cooperation, the friendly exchange and joint training of Chinese and Japanese graduate students will be enhanced.

The QIBEBT has been working with the Tokyo Metropolitan University for over ten years. The two parties officially signed a memorandum of understanding in 2014, and completed the renewal in 2019. Various forms and fruitful exchanges and cooperation have been carried out by both parties, such as exchange and joint training of students and young scientists, high-level talent academic communication on a regular basis, and joint research. Up to now, the collaborators have jointly published 9 high-level academic papers, exchanged more than 60 people, and successfully established a high-end bilateral academic platform between China and Japan, and a trilateral one among China, Japan and Korea.

 Professor Kiyoshi Kanamura is a professor at the Tokyo Institute of Applied Chemistry and the Institute of Urban Environmental Sciences at Tokyo Metropolitan University. His research interests focus on materials and assembly technology of battery. Prof. Kanamura has published 48 books and more than 200 scientific papers, 66 reviews and 14 letters. He has won the Japan Electrochemical Association Sano Award, Electric Vehicle Research Association Award and the International Electrochemical Society Research Award (2005) awards; served as a juror of NEDO, JST and chairman of the Japan Industrial Standards Committee of Rechargeable Battery. He also is member of project committee of NEDO Battery Road Map-2013, and the project leader of the JST-ALCA project “All Solid State and Other Batteries”. Prof. Kanamura is technical consultant for large battery companies such as Toshiba, JS Yuasa, Matsushita, Samsung, etc.