Composite Nanofibers as Advanced Materials for Li-ion, Li-O₂ and Li-S Batteries

The quest to increase the energy density and improve the cycle life performance of lithium ion batteries (LIBs) and beyond has led to the development of various suitable and alternative materials for energy storage and conversion. The morphology and electrode architecture in advanced battery materials have been re-designed into nanofibers and composite nanofibers. Nanofiber-based separators and electrodes have demonstrated to improve the energy density and cycling performance of LIBs. The improvement in the structure and morphology of nanofibers in LIBs such as LiSi and LiSn, have once again ignited the interest in these Li:M alloy anodes as alternative anode and cathode materials. The major challenges that confront this new frontier have the lack of scalable method among the various techniques and designing nanofibers with good structure and morphology that could prevent dendrite penetrations. However, there seems to be a solution in sight with the advent of mass production techniques such as electrospinning and Forcespinning^® that have recently been developed. In this paper, the use of nanofibers and composite nanofibers as electrode and separator materials for lithium ion, Li-O₂ and Li-S batteries is reviewed. The discussion focuses on the performance characteristics of these nanostructured electrode and separator materials and methods used to improve their performances.