Outstanding cycle stability and rate capabilities of the all-solid-state Li–S battery with a Li7P3S11 glass-ceramic electrolyte and a core–shell S@BP2000 nanocomposite

Abstract

All-solid-state Li–S batteries (ASSLSBs) can substantially alleviate poly-sulfide shuttling, which greatly improves the electrochemical performance of Li–S batteries. However, poor cycling and rate performances are still severe challenges for ASSLSBs and are mainly ascribed to the low ionic conductivity of the solid electrolyte and the unstable cathode/solid electrolyte interface resulting from the volume variation during the repeated charge–discharge process. In consideration of this, a Li₇P₃S₁₁ glass-ceramic solid electrolyte with high ionic conductivity and a S@BP2000 nanocomposite with a core–shell structure are introduced to fabricate a novel ASSLSB in this work. As expected, the S@BP2000 cathode in the fabricated ASSLSB displays outstanding specific capacity (1391.3 mA h g⁻¹, 0.2 C) and rate performance (678.6 mA h g⁻¹, 4 C) and ultrahigh cycling performance (capacity retention of nearly 100% after 1200 cycles, 3 C) at room temperature. Moreover, further improved specific capacity (1597.7 mA h g⁻¹, 0.2 C) and rate performance (1092.9 mA h g⁻¹, 8 C) can be obtained at 80 °C, benefiting from the improved ionic conductivity at higher test temperature. The ultrahigh cycling and rate performances indicate that this strategy may provide a tremendous opportunity for constructing high-performance ASSLSBs.