Boron-Doped\nand Carbon-Controlled Porous Si/C Anode\nfor High-Performance Lithium-Ion Batteries

Abstract

Silicon\nis a promising anode material for next generation lithium-ion\nbatteries due to its high capacity and low discharge potential. Commercial\nsilicon anodes are normally integrated with high graphite content\nto overcome their low electrical conductivity and huge cycling-induced\nvolume change. However, this weakens the high specific capacity advantage\nof the silicon anode. Herein, a facile method based on the dealloying\nreaction of Mg₂Si with CO₂ and B₂O₃ was demonstrated for the synthesis of porous boron-doped\nsilicon with low carbon content (pBSi-LC). Furthermore, the pBSi-LC\nanode showed high initial Coulombic efficiency of 89.3%, excellent\nrate performance (reversible capacity of 842 mAh g^–1 at a high current density of 5A g^–1), and long\ncycle stability (reversible capacity of 860 mAh g^–1 at a current density of 2 A g^–1 after 250 cycles).