Facile synthesis of a mixed-conductive Li2S composites for all-solid-state lithium-sulfur batteries

Abstract

The poor interface between the active materials, solid electrolytes, and conductive additives in composite cathode materials is the key factor restricting the performance of the all-solid-state lithium-sulfur battery. Here, the composite cathode material was prepared through the method of one-step ball milling. The sulfide electrolyte Li3PS4 (LPS) was formed on the surface of the active material Li2S while the conductive additives were incorporated, and the conductive ions and electronic network were constructed simultaneously. After adding an appropriate amount of carbon nanotubes (cnt), the composite cathode exhibited high specific capacity of 1145.2 mAh g−1 after 30 times of cycling at a current density of 0.2 mA cm−2, and the battery with ultrahigh areal Li2S loading also displays high capacity of 962.6 mA g−1. The composite cathode with high Li2S content (56.3%) was prepared, with excellent performance exhibited: the capacity is 741 mAh g−1 after 30 times of cycling at a current density of 0.2 mA cm−2.