| Rechargeable Lithium-ion batteries (LIBs) have been widely used in small-sized portable electronics due to their relatively high energy density and long cycle life. Recent years, LIBs applied in electric/hybrid vehicles has attracted extensive attention with the aim of alleviating the global energy crisis and related environmental issues. Because of this expanding application, it is crucial to develop LIBs with higher energy and power density. Meanwhile, wearable devices become popular in our daily life gradually and develop wearable electrodes for them attracts a lot of attention.Herein, we prepared a soft carbon/hard carbon composite nanofibers through a simple electrospinning method. After stabilization and carbonization, carbonized nanofibers (CNFs) web were flexible and were directly used as anode material for lithium-ion batteries. The CNFs possess a synthesis electrochemical characteristics of hard carbon and soft carbon materials, display a large reversible capacity, excellent cycle performance and good rate capability. The CNFs carbonized at 700℃ delivers a high initial reversible capacity of 693.8 mAh g-1, much higher than the theoretical specific capacity of graphite. The electrodes also display excellent rate capability and cycle stability. It delivers a reversible capacity of 235 mAh g-1 at 2 A g-1 and 288 mAh g-1 at 0.2 A g-1 after 200 cycles.Tin-based materials are a promising anodes for LIBs due to their high specific capacity and better safety performance. However, the cycle stability of Tin-based materials is poor for the high volume expension during Sn-Li alloying which results anodes break up and fall off from the current collector. Herein, we prepared a Sn@C hollowed composite nanofibers, the cavities can storage electrolyte and decrease the diffusion path of Li-ions. The Sn@C anodes show good cycle stability for their unique structures and delivers a reversible capacity of 443 mAh g-1 at 0.2 A g-1 after 100 cycles.
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