Anions with a Dipole: Toward High Transport Numbers in Solid Polymer Electrolytes
作者:Maria Martinez-Ibañez、Eduardo Sanchez-Diez、Uxue Oteo、Ismael Gracia、Itziar Aldalur、Hany B. Eitouni、Mario Joost、Michel Armand、Heng Zhang
DOI:10.1021/acs.chemmater.2c00285
日期:2022.4.12
Solid-state lithium metal (Li°) batteries (SSLMBs) are believed to be the most promising technology to satisfy the high energy demand, meet the safety requirements, and overcome the limitations ascribed to currently used Li-ion batteries. Solid polymer electrolytes (SPEs) arise as the best candidates mainly due to their easy manufacturing, flexibility, and cost compared to their inorganic counterparts. However, conventional lithium bis(trifluoromethanesulfonyl)imide and poly(ethylene oxide)-based SPEs suffer from a low lithium-ion transference number (TLi+) and poor Li° electrode compatibility as demonstrated by the compromised cyclability of these electrolytes in SSLMBs. Herein, we report the performance of SPEs comprising a newly designed N-ethyl-N-methyl-functionalized sulfonimide lithium salt, with wide electrochemical stability, decreased anionic diffusivity, sufficient Li-ion conductivity, and superior compatibility with the Li° electrode.
固态锂金属(Li°)电池(SSLMB)被认为是最有希望满足高能量需求、满足安全要求并克服目前使用的锂离子电池局限性的技术。固体聚合物电解质(SPEs)之所以成为最佳候选材料,主要是因为与无机电解质相比,它们易于制造、灵活且成本低廉。然而,传统的双(三氟甲磺酰基)亚胺锂和聚环氧乙烷基固态聚合物电解质存在锂离子转移数(TLi+)低和锂电极兼容性差的问题,这一点从这些电解质在 SSLMB 中的循环性受到影响可以看出。在此,我们报告了由一种新设计的 N-乙基-N-甲基官能化磺酰亚胺锂盐组成的固相萃取剂的性能,这种固相萃取剂具有广泛的电化学稳定性、较低的阴离子扩散性、足够的锂离子传导性以及与锂电极的良好兼容性。