Electrochemical properties of PVP-derived carbon nanospheres with various porosity and heteroatom contents in anode voltage range over full-cell operation

Porous and heteroatom-doped carbon nanostructures were investigated to address the low specific capacity and poor rate capability of the graphite anode. For successful application to commercial lithium-ion batteries, the electrochemical performances of the porous and heteroatom-doped carbon nanostructures should be evaluated in the full-cell operating voltage window. Herein, polyvinylpyrrolidone (PVP)-derived carbon nanospheres with various morphological and atomic structures were prepared by electrospraying and controlled thermal-treatment processes conducted under various thermal oxidation termination temperatures. The carbonaceous microstructures, chemical compositions, and pore structures of the PVP-derived carbon nanospheres were thoroughly examined, while their cycling and rate performances were investigated in the voltage range of 0.01–1.5 V (the normal anode operating range of the full-cell). We identified the ideal carbonaceous anode material conditions, i.e., high carbon and nitrogen content with low oxygen content for high and reversible capacity and rate performances, and small particle size with low surface area and porosity for long life. Our work demonstrates that optimizing porosity and heteroatom composition is crucial for developing commercially viable carbonaceous anode materials.