Highly uniform silicon nanoparticle/porous carbon nanofiber hybrids towards free-standing high-performance anodes for lithium-ion batteries

Abstract

Novel silicon nanoparticle/porous carbon nanofiber (Si/PCNF) hybrids with high Si loading (52wt.%) have been designed and fabricated through a simple electrospinning. The Si/PCNF of uniform fiber diameter has exhibited high specific surface area and unique porous structure. The continuous three-dimensional porous carbon networks have effectively provided strain relaxation for Si volume expansion/shrinkage during lithium insertion/extraction. In addition, the carbon matrix could largely minimize the direct exposure of Si to the electrolyte, thus substantially improving the structural stability of Si. Moreover, the porous structure could also create efficient channels for the fast transport of lithium ions. As a consequence, this novel Si-based hybrid material has exhibited stable cycling performance (ca. 870mAhg−1 at 0.1Ag−1 after 100 cycles) in the absence of binders and conducting additives, promising great potential as a free-standing anode for lithium ion batteries.