SU-8 photoresist-derived electrospun carbon nanofibres as high-capacity anode material for lithium ion battery

A binder-free carbon nanofibres web over stainless-steel wafer current collector was fabricated by controlled pyrolysis of electrospun SU-8 photoresist nanofibres. Electrochemical performance of the as-prepared carbon nanofibres web was investigated by performing charge–discharge experiments at different current densities. At low current density (37.2 $$\hbox { mA } \hbox {g}^-1, $$ 0.1C), SU-8-derived carbon nanofabric showed a large initial discharge capacity (1417 $$\hbox { mAh } \hbox {g}^-1)$$ with sufficiently higher initial coulombic efficiency ( $$\sim $$ 55%). More importantly, this carbon nanofibres web also exhibited excellent rate performance with considerably higher specific capacities at higher current densities (358 $$\hbox { mAh } \hbox {g}^-1$$ at 1C). This superior electrochemical performance, in particular at high current rates, can be attributed to small lithium ion diffusion length and resilience in entangled carbon nanofibres to accommodate volume changes during charging and discharging.