Addressing interface elimination: Boosting comprehensive performance of all-solid-state Li-S battery

Eliminating interfacial incompatibility and creating smooth ions/electrons transport at the interfaces of cathode│electrolyte│anode, are keys for the practical application of all-solid-state lithium-sulfur battery (ASSLSB). Here, we report a fully integrated-ASSLSB (i-ASSLSB) whose interfacial resistances are suppressed by the segmental motion of polyethylene oxide in hierarchical polymer electrolyte throughout the whole battery system. The mobility of ethylene oxide segments and strength of polyelectrolyte membranes can be controlled by the cross-linking degree of single-ion conductive polyelectrolyte. Such a i-ASSLSB without distinct interface achieves liquid-state-level lithium-ion diffusion coefficient of 2.4 × 10−12 cm2 s−1 and demonstrates a remarkable capacity up to 1428 mA h g−1 at 0.05 C and 100-cycle stability at 0.1 C. This work promises a valuable technical approach of interface modulation for high-performance all-solid-state lithium-sulfur batteries.