School of Mechanical Engineering Seminar
Monday, October 19, 2015 at 15:00
Wolfson Building of Mechanical Engineering, Room 206
Design, Synthesis and Electrochemical Characterizations of Electrode Materials for Rechargeable Na Ion Batteries
Do Kyung Kim
Professor, Department of Materials Science and Engineering
Dean, Office of Academic Affairs
KAIST (Korea Advanced Institute of Science and Technology),
Daejeon, Republic of Korea
(dkkim@kaist.ac.kr, http://mse2.kaist.ac.kr/~ncrl)
Although lithium ion rechargeable batteries are dominant the mobile devices and electric vehicles in the present, there are still some limitations in terms of cost and lithium reserves in the world. In that sense, interests on Na-based electrode materials have been revisited due to the abundance and low cost of sodium in recent years. I will present some of our recent efforts to make Na electrode materials have good electrochemical performance, as well as new materials with a distinctive structure. In first in the talk, I will discuss the structural and electrochemical properties of Na0.44MnO2, which is one of the promising cathode materials for Na ion batteries, in both aqueous and nonaqueous electrolytes. In search of other materials similar to Na0.44MnO2 to understand and verify the electrochemical properties of one-dimensional (1-D) tunnel structures, a new sodium ion intercalation material, Na2.7Ru4O9 with a similar 1-D tunnel structure to, but different polyhedral networks from, that of Na0.44MnO2, will be introduced. In addition, I will also introduce a simple synthetic approach to anchor materials on reduced graphene oxide surfaces to overcome the rate problems of Na-based electrode materials. Na3V2(PO4)3 with NASICON structure have been grown on graphene surface and this composite exhibits superior capacity retention at high rates and excellent cycleability. In the last part of talk, our recent works on Na2FeP2O7 cathode for aqueous Na-ion battery will be presented.
Biography (Do Kyung Kim)
Kim joined the faculty of Department of Materials Science and Engineering, KAIST in 1994. He received his B.S.degree from Seoul National University in 1982 and earned M.S. and Ph.D. from Department of Materials Science and Engineering of KAIST in 1984 and 1987, respectively. Before joining KAIST, he worked for the Agency for Defense Development(1987-1994), Korea. He had spent several visiting professor positions in UC San Diego(1992), NIST(2002), and UC Berkeley(2008). He was awarded a Top 20 Most Outstanding Research Award from Korea Science and Engineering Foundation (KOSEF) in 1997 and Top Most Outstanding Research Award from Korea Research Foundation (KRF) in 2011. His work also was selected as KAIST Top 10 Research in 2012. He has authored more than 150 technical articles, and has filled 17 Patents in US, Japan and Korea. Recently, he has been selected as a Fellow of the American Ceramic Society.
