Graphite/Li7P3S11 composite prepared by “seed” process for all-solid-state batteries

Abstract

All-solid-state lithium batteries based on sulfide solid electrolytes have the potential to deliver the high safety and energy density required for applications such as electric vehicles. Here, a graphite/Li7P3S11 composite was prepared by liquid-phase following a so-called “seed” process, in which Li2S coated on graphite was used as the “seed” for the direct formation of the Li7P3S11 solid electrolyte on the surface of the graphite particles. An all-solid-state half-cell constructed using the prepared graphite/Li7P3S11 composite exhibited a discharge capacity of 309 and 372 mAh g−1 at the C-rate of C/8 and at 25 °C and 100 °C, respectively. The electrochemical performance of the all-solid-state cell at different C-rates was evaluated at 100 °C. A relatively high discharge capacity of 168 mAh g−1 was retained at the high C-rate of 2C.