X-ray Absorption Spectroscopy Characterization of a Li/S Cell

Nanomaterials

Yifan Ye¹  Ayako Kawase⁵  Min-Kyu Song³  Bingmei Feng²  Yi-Sheng Liu²  Matthew A. Marcus²  Jun Feng²  Elton J. Cairns⁵  Jinghua Guo²  Junfa Zhu¹  Andy (Xueliang) Sun⁴ 

[1] National Synchrotron Radiation Laboratory and Collaborative Innovation Center of Suzhou Nano Science and Technology, University of Science and Technology of China, Hefei 230029, China;Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA;School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164, USA;;National Synchrotron Radiation Laboratory and Collaborative Innovation Center of Suzhou Nano Science and Technology, University of Science and Technology of China, Hefei 230029, ChinaEnvironmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA;

关键词: lithium/sulfur cell;    X-ray absorption spectroscopy;    cetyltrimethylammonium bromide;    synthesis;    capacity decay;    cycled cathode materials;    insulating layer;    in-situ/in-operando;   

DOI  :  10.3390/nano6010014

来源: mdpi

【 摘 要 】

The X-ray absorption spectroscopy technique has been applied to study different stages of the lithium/sulfur (Li/S) cell life cycle. We have investigated how speciation of S in Li/S cathodes changes upon the introduction of CTAB (cetyltrimethylammonium bromide, CH₃(CH₂)₁₅N⁺(CH₃)₃Br⁻) and with charge/discharge cycling. The introduction of CTAB changes the synthesis reaction pathway dramatically due to the interaction of CTAB with the terminal S atoms of the polysulfide ions in the Na₂S_x solution. For the cycled Li/S cell, the loss of electrochemically active sulfur and the accumulation of a compact blocking insulating layer of unexpected sulfur reaction products on the cathode surface during the charge/discharge processes make the capacity decay. A modified coin cell and a vacuum-compatible three-electrode electro-chemical cell have been introduced for further in-situ/in-operando studies.

【 授权许可】

CC BY   
© 2016 by the authors; licensee MDPI, Basel, Switzerland.