Anodic performance of vapor-derived carbon filaments in lithium-ion secondary battery Original Research Article

The electrochemical characteristics of vapor-derived carbon filaments of diameter 0.1 μm were studied by charge–discharge testing of a lithium-ion secondary cell with a lithium metal electrode. After activation, followed by either nitridation or reduction in hydrogen, vapor-derived carbon filaments show high reversible charge and discharge capacities. An ordered structure and a large pore size are favorable for a high capacity, as shown by comparison of vapor-derived and pitch-derived carbons. The combination of a high specific surface area and a large amount of oxygen-containing surface functional groups results in a high irreversible capacity. To improve the anodic performance, it is important to control the surface microstructure by decreasing the surface oxygen content by nitridation or reduction in H2, while maintaining order in the crystallographic structure with surface mesoporosity.