A high-performance tin dioxide@carbon anode with a super high initial coulombic efficiency via a primary cell prelithiation process

Highlights: • Initial coulombic efficiency of SnO₂-based anode materials is improved by a primary cell prelithiation process. • The prelithiation process is controllable. • This prelithiated SnO₂@C keeps excellent cycling performance and rate capability. Recently, many exciting achievements have been made in improving the cycling performance of SnO₂-based electrode. However, the low initial Coulombic efficiency of SnO₂-based electrode caused by the formation of solid electrolyte interphase and some of the irreversible formation of Li₂O in SnO₂ structure still remains unresolved. Here this work reports a primary-cell process to prelithiate the SnO₂-based composites to compensate the irreversible loss during the first cycle. The primary-cell-prelithiated SnO₂@C composites performs a high initial Coulombic efficiency from 92.7% to >100% with the prelithiation time extends. Even after 600 cycles, the prelithiated (24 h) SnO₂@C composites show a high capacity retention of 95% (848 mAh g⁻¹) at a current density of 0.5 A g⁻¹.