A gel polymer electrolyte based lithium‑sulfur battery with low self-discharge

Abstract Lithium‑sulfur batteries have gained intensive attention due to their large capacity. However, their application was limited because lithium‑sulfur battery has suffered from fast capacity fading and severe self-discharge. In this work, gel polymer electrolyte (GPE) was proposed and demonstrated as an effective way to solve those problems. This gel polymer electrolyte can reduce the dissolution and diffusion of intermediate lithium polysulfides, improving the cycle life of and mitigating self-discharge of the lithium‑sulfur battery. When fabricated as a quasi-solid-state battery, a very good cycling stability with capacity retention of 72% at current density of 835 mA g − 1 (0.5 C) after 100 cycles can be obtained. In addition, the battery shows very low self-discharge behavior. When the battery was rest at fresh, half-discharged, half-charged or full charged state for 24 h, it shows almost no capacity decay. These results demonstrated a promising restrained polysulfide shuttle process toward practical lithium‑sulfur applications.