[3PS-014]
Promoting Granular Lithium Sulfide Growth by Soft Acidic–Hard Basic Ionomer Binder for Lithium‒Sulfur Batteries
발표자김다은 (연세대학교)
연구책임자이상영 (연세대학교)
Abstract
Electrode passivation limits the reversibility of Li–S batteries. Pivoting from the prevailing approaches that focus on electrode active materials and electrolytes, herein, we introduce a class of S electrode binders based on soft acidic–hard basic (SAHB) ionomers. The SAHB binder contains a soft cation (tetraallyl ammonium ion, TA+) paired with a hard counter anion (nitrate, NO3–), allowing matched interactions with Li polysulfides via soft acid–soft base (TA+–Sx2‒) and hard base–hard acid (NO3––Li+) pairings. This intermolecular coupling retards LiPS diffusion, promoting three-dimensional granular Li sulfide growth, guided by a high Damköhler number. Consequently, the SAHB binder enables a Li–S cell to achieve a high specific capacity of 1545 mAh gsulfur–1 and stable capacity retention (71.5% after 300 cycles at a current density of 1 C), outperforming previously reported S electrode binders.