Stabilization of Li–S batteries with a lean electrolyte via ion-exchange trapping of lithium polysulfides using a cationic, polybenzimidazolium binder

Chuyen Van Pham,Simon Thiele,Lili Liu,Steven Holdcroft,Benjamin Britton,Michael Walter

doi:10.1039/c9se01092k

Abstract

An active cationic polymer binder absorbs dissolved polysulfides for suppressing the shuttle effect and simultaneously forms a Li+ conducting phase, allowing Li–S cells to work at a lean electrolyte content.

Highlights

Batteries are nowadays indispensable components in industrial applications such as portable electronic devices and power sources in electric vehicles
High order Li2Sx (x 1⁄4 4–8) species dissolve in the electrolyte and escape from the cathode, driven by a concentration gradient
LiI might play a positive role in stabilization of the solid electrolyte interface (SEI) layers as proved previously.[28]

Summary

Introduction

Batteries are nowadays indispensable components in industrial applications such as portable electronic devices and power sources in electric vehicles. The conversion reactions, S % Li2S, cause a >75% volume expansion/contraction which leads to their disintegration.[6] The low electrical conductivity (10À30 S cmÀ1) of polysulfur (S8) and the discharge products (e.g. Li2S and Li2S2) further limits both S utilization and battery rate capability.[7] To address these obstacles, Nazar and coworkers[8] introduced the concept of using highly ordered, mesoporous carbon to con ne sulfur and polysul des. These S cathode structures were found to substantially enhance the cycle life and charge capacity and revived the 1180 | Sustainable Energy Fuels, 2020, 4, 1180–1190

Methods

Results

Conclusion