X-ray Absorption Spectroscopy Characterization of a Li/S Cell.
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 Na₂Sxsolution. 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 furtherin-situ/in-operandostudies.
National Synchrotron Radiation Laboratory and Collaborative Innovation Center of Suzhou Nano Science and Technology, University of Science and Technology of China, Hefei 230029, China. yifanye@lbl.gov.|Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. yifanye@lbl.gov.
Yifan
Y
Ye
Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. akawase@lbl.gov.|Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA. akawase@lbl.gov.
Ayako
A
Kawase
School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164, USA. mksong325@gmail.com.
Min-Kyu
MK
Song
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. bfeng@lbl.gov.|School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China. bfeng@lbl.gov.
Bingmei
B
Feng
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. ysliu2@lbl.gov.
Yi-Sheng
YS
Liu
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. mamarcus@lbl.gov.
Matthew A
MA
Marcus
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. fjun@lbl.gov.
Jun
J
Feng
Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. ejcairns@lbl.gov.|Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA. ejcairns@lbl.gov.
Elton J
EJ
Cairns
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. jguo@lbl.gov.|Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064, USA. jguo@lbl.gov.
Jinghua
J
Guo
National Synchrotron Radiation Laboratory and Collaborative Innovation Center of Suzhou Nano Science and Technology, University of Science and Technology of China, Hefei 230029, China. jfzhu@ustc.edu.cn.
Junfa
J
Zhu
X-ray absorption spectroscopy; capacity decay; cetyltrimethylammonium bromide; cycled cathode materials; in-situ/in-operando; insulating layer; lithium/sulfur cell; synthesis