High energy and sustainable solid-state lithium-sulfur battery enabled by the force-bearing cathode and multifunctional double-layer hybrid solid electrolyte

In this study, we propose an advanced model for a high-performance solid-state lithium-sulfur battery (LiSB) by combining a force-bearing cathode and a multifunctional double-layer hybrid solid electrolyte (DLHSE). The designed cathode is fabricated by the sulfur-loaded carboxylated-carbon nanotube (S@CNT-COOH) and the ionic liquid (IL) encapsulated 5-sulfoisophtalic acid monolithium-anchored poly(vinyl alcohol) (IL@PVA-SPALi) conductive binder, and it exhibits desirable flexibility, high adhesive strength of 22.3 MPa with the aluminum current collector, and excellent Li+ conductivity of 1.3 × 10−3 S cm−1. Accompanied by this cathode, the present DLHSE membrane offers an effective polysulfide impermeation and impressive lithium dendrite suppression by the ultrathin IL-impregnated metal–organic framework layer and IL@PVA-SPALi electrolyte. The DLHSE shows outstanding Li+ conductivity of 9.6 × 10−4 S cm−1 and a high Li+ transference number of 0.72 at room temperature in a wide electrochemical window up to 5 V vs Li+/Li, maintaining the long-term stability with Li metal over 1000 h and low interfacial resistance of 56 Ω with the designed cathode. Based on those excellent properties, the LiSB assembled with the force-bearing cathode and DLHSE exhibits a high specific discharge capacity of 1250 mAh/g at 0.2C and long-term cyclic stability at 93.69% of the initial capacity after 200 cycles of charge/discharge processes.