Carbon-encapsulated silicon ordered nanofiber membranes as high-performance anode material for lithium-ion batteries

Silicon have attracted much attention as a promising anode material for lithium-ion batteries due to the extremely high theoretical capacity. However, its practical application is limited by the huge volume expansion during the cycling process. To address this issue, carbon-encapsulated silicon ordered nanofiber membranes were designed through a modified electrospinning technology with a strong magnetic field. Compared with the conventional nanofiber membranes, the optimized M1200 Gs anode exhibited a high discharge capacity of 1603.1 mAh·g -1 at 0.1 A·g -1 , a superior rate performance, and a robust cycling stability with a reversible capacity of 658.1 mAh·g -1 at 1 A·g -1 after 100 cycles. The improved electrochemical performance was confirmed to be highly correlated with the parallel structure of nanofibers, which help to facilitate the diffusion and transport of electrons and ions, realize the stress distribution and buffer the volume changes. This work provides unique insights into designing silicon-based anodes with novel structures for lithium-ion batteries. Figure 1 Silicon have attracted much attention as a promising anode material for lithium-ion batteries due to the extremely high theoretical capacity. However, its practical application is limited by the huge volume expansion during the cycling process. To address this issue, carbon-encapsulated silicon ordered nanofiber membranes were designed through a modified electrospinning technology with a strong magnetic field. Compared with the conventional nanofiber membranes, the optimized M1200 Gs anode exhibited an excellent discharge capacity of 1603.1 mAh·g -1 at 0.1 A·g -1 , a superior rate performance, and a robust cycling stability with a high charging capacity of 658.1 mAh·g -1 at 1 A·g -1 after 100 cycles. The improved electrochemical performance was confirmed to be highly correlated with the parallel structure of nanofibers, which help to facilitate the diffusion and transport of electrons and ions, realize the stress distribution and suppress the volume changes. This work provides unique insights into designing silicon-based anodes with novel structures for lithium-ion batteries. • A strong magnetic field is introduced to the electrospinning technology. • Carbon-encapsulated silicon ordered nanofiber membranes are prepared through the modified electrospinning technology. • The composite exhibits high stability and good electrochemical performance.