MgSiO3 doped, carbon-coated SiOx anode with enhanced initial coulombic efficiency for lithium-ion battery

Abstract

Silicon suboxide (SiO_x) is considered as a potential negative material for next-generation lithium-ion battery (LIB). However, the relative low initial coulombic efficiency (ICE) hindered the development of SiO_x. Herein, we report a two-step magnesiothermic reduction method to synthesize carbon-coated MgSiO₃ doped SiO_x particles (MgSiO₃–SiO_x@C), endowing it with superb properties as the anode of LIB. Comprehensive characterization demonstrates the as-prepared MgSiO₃–SiO_x@C can increase the ICE and releasing volume expansion. As such, the MgSiO₃–SiO_x@C nano-architectures exhibit a high ICE of 85.4 %, meanwhile, it also shows relatively stable cycling performance of 759.2 mAh g⁻¹ after 100 cycles at 0.5C with the capacity retention of 59.8 %. The lithium ion full battery with LiNi_0.8Mn_0.1Co_0.1O₂ as positive electrode proves the feasibility of its practical application, which delivers a stable reversible capacity of 89.2 mAh g⁻¹ after 150 cycles at 1C with a capacity retention of 62.7 %.