Leveraging Lithium‐Bond Chemistry in a Tailored Electrolyte to Control Sulfur and Lithium Evolution in Li–S Batteries

Abstract

ABSTRACT Rational regulation of lithium polysulfide reaction kinetics, coupled with strategies for stabilizing the Li anode, constitutes a cornerstone for lithium–sulfur (Li–S) chemistry. Herein, we propose phthalocyanine (Pc) as a homogeneously dispersed promoter in the electrolyte for Li–S batteries, based on its N 8 ‐cavity planar rigid structure featuring an electron‐rich macrocyclic core. Under the optimized concentration of Pc in electrolyte, we reveal that the Li─N coordination bonds between Li 2 S 8 and Pc in the catholyte of Li–S batteries, which significantly contribute to the catalytic conversion of sulfur species. Meanwhile, Pc molecules in the anolyte preferentially adsorb onto the Li anode surface, forming a dense molecular layer by virtue of Li─N bonding, which effectively enhances interfacial desolvation kinetics and thereby promotes uniform Li deposition. Enabled by the promoted Li–S chemistry through Li─N bonds, the battery with Pc enabler achieves a low decay rate of 0.0479% per cycle after 600 cycles at 1C. More remarkably, 1.07 Ah pouch cells deliver a high energy density of 325.5 Wh kg −1 , serving as a compelling design strategy for leveraging sustainable Li─N bond chemistry to achieve high‐rate and long‐life Li–S battery technology.