Enhanced Li-storage performances of dually-protected CoGeO3 nanocomposites as anode materials for lithium ion batteries

A facile route to dually-protected CoGeO3 nanoparticle hybrids has been established. Reduced graphene oxide(rGO)-covered and carbon-encapsulated CoGeO3 nanoparticles were utilized as anode materials for Li ion batteries. Such a rationally designed structure could effectively accommodate the volume expansion of CoGeO3 nanoparticles during Li-cycling. As a consequence, remarkable electrochemical performances, i.e. high first discharge capacity (2000 mAh g−1) and charge capacity (1300 mAh g−1), excellent reversible capacity of 782 mAh g−1 after 50 cycles under a current density of 200 mA g−1, and outstanding rate performance, have been garnered for CoGCs/C-4 composite electrodes, in which electrochemically active materials contained 19.5 wt% rGO and 3.7 wt% pyrolytic carbon. These advantageous attributes make dually-protected CoGeO3 particles the potential anode materials for LIBs.