Electrospun flexible Si/C@CNF nonwoven anode for high capacity and durable lithium-ion battery

Abstract Herein, we propose a silicon/carbon@carbon nanofiber (Si/C@CNF) nonwoven with 40 wt% Si loading as a high performance anode to realize flexible, stable and high energy density batteries application. In the Si/C@CNF composite, PVP-carbon as the conductive network is introduced in the core of fibers. Such carbon network connects each Si nanoparticle and greatly improves the high rate stability of Si/C@CNF nonwoven anode. The optimal Si/C@CNF anode delivers a reversible capacity as high as 1506.5 mA h g -1 at 0.1 A g-1 and outstanding rate performance of 555.0 mA h g-1 at a high current density of 2 A g-1. After 500 electrochemical cycles at a current rate of 0.2 A g-1, the reversible capacity retention is up to 86%. The Coulombic efficiencies are close to 100%. The superior properties of Si/C@CNF flexible nonwoven anode make this material attractive for further flexible and high energy density LIBs applications.