Remarkable High-temperature Performance of Hollow Co9S8 Nanoparticles Integrated with Carbon Materials for Lithium-ion Batteries

A solution-based “hot-injection” approach was developed to synthesize amorphous carbon-decorated and graphene-anchored hollow Co9S8 nanoparticles as anode material for Li ion battery application. Such a rationally designed dually-protected structure could effectively accommodate the volume expansion of Co9S8 nanoparticles during Li-cycling. As a result, as-synthesized nanocomposites could be successfully operated under ultrawide temperature window of −20 °C-70 °C, rendering excellent electrochemical performances, i.e., remarkable reversible capacities of 910 mA h g−1 after 100 cycles (at 500 mA g−1) and 622 mA h g−1 after 200 cycles (at 1000 mA g−1) at 70 °C. These attributes enable three-dimensional structured Co9S8 nanoparticles to be promising anode materials of advanced Li-ion batteries for large-power applications such as electric vehicles under extreme temperature environments.