A B- and F-enriched buffering interphase enables a high-rate and high-stability SiO x /C anode.

A facile, universal surface engineering strategy is proposed to address the volume expansion and slow kinetic issues encountered by SiO x /C anodes. A B-/F-enriched buffering interphase is introduced onto SiO x /C by thermal treatment of pre-adsorbed lithium salts at 400 °C. The as-prepared anode integrates both high-rate performance and long-term cycling durability.