AUTHOR=Cui Yongliang , Liu Sufu , Liu Bo , Wang Donghuang , Zhong Yu , Zhang Xuqing , Wang Xiuli , Xia Xinhui , Gu Changdong , Tu Jiangping TITLE=Bi-containing Electrolyte Enables Robust and Li Ion Conductive Solid Electrolyte Interphase for Advanced Lithium Metal Anodes JOURNAL=Frontiers in Chemistry VOLUME=7 YEAR=2020 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2019.00952 DOI=10.3389/fchem.2019.00952 ISSN=2296-2646 ABSTRACT=

The notorious lithium dendrite growth, causing the safety concern, hinders the practical application of high-capacity Li metal anodes for rechargeable batteries. Here, a robust and highly ionic conductive solid electrolyte interphase (SEI) layer to protect Li metal anode is in-situ constructed by introducing trace additive of tetrapotassium heptaiodobismuthate (K4BiI7) into electrolyte. The K4BiI7-added electrolyte enables Li metal anode to display a stable cycling for over 600 cycles at 1.0 mA cm−2/1.0 mAh cm−2 and over 400 cycles at 5.0 mA cm−2/5.0 mAh cm−2. In situ optical microscopy observations also conform the suppression of Li dendrites at high current density. Moreover, the in-situ SEI layer modified Li anode exhibits an average Coulombic efficiency of 99.57% and less Li dendrite growth. The Li-S full sells with the modified electrolyte also show improved electrochemical performance. This research provides a cost-efficient method to achieve a highly ionic conductive and stable SEI layer toward advanced Li metal anodes.