High Energy Density Sulfur-Rich MoS6-Based Nanocomposite for Room Temperature All-Solid-State Lithium Metal Batteries

摘要

The all-solid-state lithium–sulfur battery is considered to be a promisingenergy device due to high energy density and excellent safety. However, sulfursuffers from its insulating nature and large volume changes. Employingtransition-metal sulfide cathodes is an attractive alternative. Herein, a highenergy density sulfur-rich MoS_6-based nanocomposite is designed, whereMoS_6 nanospheres are homogenously anchored on carbon nanotubes (CNTs)by a wet-chemical method, providing improved electronic conductivity andreduced volume changes. In addition, a nanosized Li7P3S11 electrolyte is insitu coated on the surface of MoS_6-CNT20 to realize intimate interface contactand form nanoscale electronic/ionic transportation networks. The resultantMoS_6-CNT20@15Li7P3S11 composite shows high electronic conductivity(1.7 × 10~(?1) S cm~(?1)) and ionic conductivity (6.7 × 10~(?4) S cm~(?1)), which areeight and three orders of magnitude improved compared to those of MoS6.The Li/Li_6PS5Cl/MoS_6-CNT20@15Li7P3S11 battery exhibits an initialdischarge capacity of 1034.32 mAh g~(?1) at 0.1 A g~(?1). In addition, an ultrahighreversible energy density of 1640 Wh kg?1 for the active material can berealized, which is the highest among all transition-metal sulfide cathodes.Moreover, it shows a reversible capacity of 550.00 mAh g_（-1） at 0.5 A g_（-1） after1000 cycles, demonstrating that the sulfur-rich MoS_6-based nanocomposite isa promising highenergy density cathode material for next-generationall-solid-state lithium batteries.