Stabilizing electrode-electrolyte interface for high-performance SiO_x anode by dual electrolyte additive

Macro- and micro-interface instability of SiOx anode caused by its dramatic volume variation during cycling will result in low Coulombic efficiency and rapid capacity degradation. In this work, an organic-inorganic composite interfacial layer rich in benzene ring groups, polyisocyanates, and LiF was obtained on SiOx anode by the introduction of 4-fluorophenyl isocyanate (FPI) and fluoroethylene carbonate (FEC) co-additives in electrolyte. The SiOx anode material shows a capacity retention of 69.2% after 100 cycles at a current density of 1 A g(-1) and rate capacity of 523 mA h g(-1) at the current density of 3 A g(-1), while the SiOx anode cycling in reference electrolyte has almost no capacity. (C) 2023 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.