A macrocyclic amine-based electrolyte for lithium–sulfur batteries: Li ion encapsulation regulates electrode performance.

This article focuses on improving lithium–sulfur (Li–S) battery performance by replacing the commonly used linear ether solvent 1,2-dimethoxyethane (DME) with a macrocyclic amine, 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane (TMTAC), in the electrolyte. TMTAC forms a robust solvation structure with lithium ions due to its cavity size and strong Li+ binding affinity, which enhances Li+ transport, promotes three-dimensional Li2S deposition on the cathode, suppresses lithium dendrite growth on the anode, and effectively reduces the polysulfide shuttle effect. Electrolytes containing TMTAC (notably the DOL/TMTAC-6 mixture) demonstrate superior ionic conductivity, cycling stability, and rate capability compared to traditional DOL/DME electrolytes, with successful application in both coin-type and pouch-type Li–S cells under practical conditions such as high sulfur loading and lean electrolyte. The study highlights the importance of tailored ion solvation and molecular recognition in electrolyte design for advancing energy storage technologies.