A Liquid‐Metal Electrocatalyst as a Self‐Healing Anchor to Suppress Polysulfide Shuttling in Lithium‐Sulfur Batteries

Abstract

AbstractLithium‐sulfur battery (LSB) is a promising next generation energy storage technology due to its high theoretical capacity, low cost, and environmental friendliness surpassing current lithium‐ion batteries. However, several challenges restrict the practical applications of LSBs. A major obstacle that limits its performance is the dissolution of long‐chain lithium polysulfides into the electrolyte which results in loss of active material and capacity fade during the charge/discharge cycles. Here, we developed a novel sulfur composite with liquid‐metal (LM) nanoparticles and reduced graphene oxide (rGO) dispensed on a carbon‐cloth electrode to achieve long cycling of LSBs. The liquid nature of the LM nanoparticles results in many advantages. It provides a strong anchoring with sulfur inhibiting the polysulfide shuttle effect. In addition, it prevents the detachment of the sulfur particles from the current collector albeit large volume changes and cracking of the sulfur during lithiation and delithiation, maintaining the electron conduction paths. This innovative composite resulted in a high discharge capacity, an outstanding capacity retention, and a high Coulombic efficiency. Our results demonstrate an effective method to suppress the polysulfide shuttle effect and pave a new path towards practical applications of LSBs by using multifunctional LM nanoparticles composites.