Compatibility of lithium oxalyldifluoroborate with lithium metal anode in rechargeable batteries

Abstract

Lithium (Li) salt is a key factor which impacts the performance of the electrolyte and electrodes for metallic Li rechargeable batteries. In this work, the compatibility of Li oxalyldifluoroborate (LiODFB) which is used as Li salt for the electrolyte with Li metal electrode is studied, and compared with Li perchlorate (LiClO4) and Li hexafluorophosphate (LiPF6). The electrochemical stability of different Li salt based electrolytes, the plating/stripping cycling performance of Li electrode in different electrolytes, the morphologies of the Li deposit formed in different electrolytes, the electrochemical kinetics of Li+ electrodeposition in different electrolytes, and the solid electrolyte interphase film formed on the electrolyte/Li electrode interface with different electrolytes are evaluated and compared. The results show that LiODFB has much better compatibility with Li metal electrode and is suitable for electrolyte in metallic Li rechargeable batteries.