Novel 2-D metal-sulfide materials for the next-generation Li/Na-ion batteries, 한국전기화학회, DCC Daejeon

Abstract

Novel 2-D metal-sulfide materials for the next-generation Li/Na-ion batteries Uijin Chang, KwangSup Eom SMSE, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Korea chujin58@gist.ac.kr Because lithium-ion has fundamental advantages that are light, small, and electrochemically active, the lithium-ion battery (LIB) using lithium-ion has high energy density, long lifetime, and high voltage. Therefore, it has been being used in all sorts of portable devices. However, presently the LIB needs high capacity per volume and weight in order to use in large scaled devices and facilities such as electric vehicles (EVs) and energy storage systems (ESSs) 1. For that reason, one of the notable materials for LIB is sulfur (S) that has five times higher theoretical capacity of 1675 as cathode. However, most of the Li-sulfur batteries have shown a fast initial capacity fading, because high-ordered polysulfides (, ) which are formed as intermediate materials of the Li-sulfur batteries dissolve in the common LIB electrolytes2. In this presentation, we introduce metal-sulfide material which can be used for a cathode instead of sulfur. In particular, MoSx (x＆ge;3) has a high capacity of more than 670 mAh/g. Moreover, it can solve the problem of sulfur dissolution by directly forming low-ordered polysulfides3. The GO@MoS3 composite is prepared by a chemical synthesis, and it formed a micro-sized sheet composing of amorphous molybdenum trisulfide along GO surface. It is very notable that this material has a tendency that the capacity gradually increases over 300 percent with the initial cycling via a continuous pulverization of the amorphous micro-sheet composites into nano-sheet and crystallines leading to a decrease in lithium-ion transport length. The result is clearly confirmed by HR-TEM and XRD analyses. References 1. Blomgren, G. E. The Development and Future of Lithium Ion Batteries. 164, 5019＆ndash;5025 (2017). 2. Manthiram, A., Chung, S. ＆ Zu, C. Lithium ＆ndash; Sulfur Batteries＆#8239;: Progress and Prospects. Volume 1980＆ndash;2006 (2015). 3. Stephenson, T., Li, Z., Olsen, B. ＆ Mitlin, D. Lithium ion battery applications of molybdenum disulfide (MoS2) nanocomposites. Energy Environ. Sci. 7, 209＆ndash;231 (2014).