Developing new solvents for lithium metal batteries (LMBs) is crucial due to the incompatibility of conventional carbonate electrolytes and the limited electrochemical windows of ether-based electrolytes. While fluorinated ethers offer improved electrochemical stability, their lithium-ion solvation ability is poor. This research introduces 2,2-dimethoxy-4-(trifluoromethyl)-1,3-dioxolane (DTDL), a novel solvent combining a cyclic fluorinated ether with a linear ether segment to achieve high voltage stability and enhanced lithium-ion solvation. DTDL demonstrates high oxidation stability (up to 5.5 V), a large lithium-ion transference number (0.75), and stable Coulombic efficiency (99.2% after 500 cycles). A LiNi0.8Co0.1Mn0.1O2 full cell using 2 M LIFSI-DTDL electrolyte shows 84% capacity retention after 200 cycles at 0.5 C.

Yan Zhao, Tianhong Zhou, Timur Ashirov, Mario El Kazzi, Claudia Cancellieri, Lars P. H. Jeurgens, Jang Wook Choi, Ali Coskun