A lithium–sulfur battery using a solid, glass-type P2S5–Li2S electrolyte

• A solid-state lithium–sulfur battery with a Li2S–P2S5 electrolyte is here reported
• The electrolyte has high ionic conductivity and excellent stability against lithium
• The lithium sulfur solid cell has a maximum capacity of 1200 mAh g− 1.
• The cell has a stable capacity of 400 mAh g− 1 vs. sulfur and a working voltage of 2.1 V
• The solid battery is proposed as advanced, safe and low-cost energy storage system.

In this work we characterize a solid-state lithium–sulfur battery using a Li2S–P2S5 glass-type electrolyte. The electrolyte is prepared by powder pellet-pressing and the effect of the applied pressure on the ionic conductivity as well as its temperature dependence is studied by electrochemical impedance spectroscopy. The lithium–sulfur battery electrochemical process is studied by potentiodynamic cycling with galvanostatic acceleration (PCGA) at an operating temperature of 80 °C. The cycling behavior of the battery is studied by repeated charge/discharge in galvanostatic conditions. The results demonstrate that the electrolyte has a conductivity ranging from 1*10−4 to 5*10−3 S cm−1 by increasing the temperature from 0 °C to 80 °C, respectively. Furthermore, the PCGA measurement shows a maximum capacity referred versus sulfur mass of the order of 1200 mAh g− 1, while the cycling test, performed at C/20, indicates a steady-state capacity of the order of 400 mAh g− 1, a working voltage of 2.1 V and a resulting theoretical energy density of 840 Wh kg− 1. Considering the results we believe that the solid-state, lithium sulfur cell with the Li2S–P2S5 electrolyte may be proposed as high-energy density battery for safe, low-cost energy storage applications.