Fast Heat Transport Inside Lithium-Sulfur Batteries Promotes Their Safety and Electrochemical Performance
Guiyin Xu,
Daiwei Yu,
Dongchang Zheng,
Shijian Wang,
Weijiang Xue,
Xiangkun Elvis Cao,
Hongxia Zeng,
Xianghui Xiao,
Mingyuan Ge,
Wah-Keat Lee,
Meifang Zhu
Affiliations
Guiyin Xu
Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Corresponding author
Daiwei Yu
Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
Dongchang Zheng
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
Shijian Wang
Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, University of Technology Sydney, Sydney, NSW 2007, Australia
Weijiang Xue
Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
Xiangkun Elvis Cao
Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA
Hongxia Zeng
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
Xianghui Xiao
National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
Mingyuan Ge
National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
Wah-Keat Lee
National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
Meifang Zhu
State Key Lab for Modification of Chemical Fibers & Polymer Materials, College of Materials Science & Engineering, Donghua University, Shanghai 201620, China; Corresponding author
Summary: Lithium-sulfur batteries are paid much attention owing to their high specific capacity and energy density. However, their practical applications are impeded by poor electrochemical performance due to the dissolved polysulfides. The concentration of soluble polysulfides has a linear relationship with the internal heat generation. The issue of heat transport inside lithium-sulfur batteries is often overlooked. Here, we designed a functional separator that not only had a high thermal conductivity of 0.65 W m−1 K−1 but also alleviated the diffusion of dissolved active materials to the lithium anode, improving the electrochemical performance and safety issue. Lithium-sulfur batteries with the functional separator have a specific capacity of 1,126.4 mAh g−1 at 0.2 C, and the specific capacity can be remained up to 893.5 mAh g−1 after 100 cycles. Pouch Cells with high sulfur loading also showed a good electrochemical performance under a lean electrolyte condition of electrolyte/sulfur (E/S) = 3 μL mg−1.
