High-Conductivity Argyrodite LiPSCl Solid Electrolytes Prepared via Optimized Sintering Processes for All-Solid-State Lithium-Sulfur Batteries.

Highly Li-ion conductive LiPSCl solid-state electrolytes (SSEs) were prepared by solid-state sintering method. The influence of sintering temperature and duration on the phase, ionic conductivity, and activation energy of LiPSCl was systematically investigated. The LiPSCl electrolyte with a high ionic conductivity of 3.15 × 10 S cm at room temperature (RT) was obtained by sintering at 550 °C for just 10 min, which was more efficient taking into account such a short preparation time in comparison with other reported methods to synthesize LiPSCl SSEs. All-solid-state lithium sulfur batteries (ASSLSBs) based on the LiPSCl SSE were assembled by using the nano-sulfur/multiwall carbon nanotube composite combined with LiPSCl as the cathode and Li-In alloy as the anode. The cell delivered a high discharge capacity of 1850 mAh g at RT for the first full cycle at 0.176 mA cm (∼0.1C). The discharge capacity was 1393 mAh g after 50 cycles. In addition, the Coulombic efficiency remained nearly 100% during galvanostatic cycling. The experimental data showed that LiPSCl was a good candidate for the SSE used in ASSLSBs.