Self-standing high-performance Si nanoparticle anchored porous carbon fiber composites for Li-ion batteries

Abstract

Silicon (Si) is a highly promising anode candidate for lithium-ion batteries. However, the huge volume change of Si during the lithiation/delithiation process might cause serious structural damage, thereby restricting its potential application. Herein, a novel self-standing electrode consisting of porous carbon coated Si (Si@p-C) nanoparticles and carbon fibers (Si@p-C/p-CF) is prepared by a facile electrospinning technique. The three-dimensional carbon fiber framework derived from polyacrylonitrile serves as the support for self-standing electrode, which exhibits superior flexibility and satisfactory electrolyte penetration ability. The porous carbon matrix on the surface of Si nanoparticles can effectively buffer the volume expansion of Si during cycling and prevent direct contact between Si and the electrolyte. Attributed to these merits, the obtained (Si@p-C)0.5/p-CF electrode exhibits outstanding cycling stability with a specific capacity of 940 mAh g−1 at 0.2 A g−1 after 400 cycles, delivering great application potential.