Novel electriferous charge-mosaic S(TMC@Lys-Li) separator towards efficient Li+ fast-transfer for high-energy density and long-duration lithium-sulfur batteries

Abstract

Lithium-sulfur (Li-S) batteries with attractive capacity give remarkable potential for prospective high-capacity application scenarios but suffer a fatal flaw of short cyclability before large-scale commercialization especially owing to polysulfide (Li₂S_n) transmembrane shuttling. To efficiently restrain chronic Li₂S_n shuttle and expedite Li⁺ transfer, herein, a novel electriferous charge-mosaic S(TMC@Lys-Li) separator preparation approach is recommended. Interfacial polymerizations of lithiated lysine and trimesoyl chloride establish an electriferous charge-mosaic polyamide functional layer. Substituted Li within the charge-mosaic layer offers transition or replacement sites for smoothing Li⁺ migrations, which constructs efficient Li⁺ fast-transfer private channels and accelerates the Li⁺ transfer rate to 9.4 times. Negatively charged polyamide skeleton synchronously heightens Li₂S_n rejections by combining Donnan and steric effects. S(TMC@Lys-Li) replenishes Li for homogenizing Li nucleation and growth, endowing stable plating/stripping behaviors over 250 cycles for Li-Cu batteries. Assembled Li-S cells thus exhibit excellent specific capacity and cyclability at multiple application scenarios such as long periods, high areal capacity, and fast charge, holding 78.1% retention after 500 cycles at 1 C. The superior thermal stability and self-discharge of S(TMC@Lys-Li) dramatically strengthen battery thermal runaway resistance even at 155 ℃, which ensures security for Li-S battery high-power and high-temperature operations. Above alluring features enable charge-mosaic separators to be potentially adopted in practical Li-S batteries demanding strict security, high-capacity density, and fast charge technology.