Abstract
Modern technology-driven society largely relies on energy storage systems or electric vehicles for eco-friendly transportation and the use of high technology devices. Lithium rechargeable batteries are the most promising power sources because of its high energy density but still have a challenge. Graphite is the most widely used anode material in the field of lithium ion secondary battery due to its many advantages such as good cyclic performances, and high charge/discharge efficiency in the initial cycle. However, its low energy density is preventing the current lithium ion secondary battery from realizing electric vehicles or energy storage systems. So, here we will show two-fold pathways to innovatively enhance the energy density of batteries for large-scale applications.
As a first way to solve this problem, we suggest Si-carbon composite nanofibers(NFs) through electrospinning as a candidate anode for lithium ion secondary battery. Electrospun Si-carbon composite NFs displayed excellent cyclic retention and coulombic efficiency due to amorphous carbon framework accommodating the inherent volume expansion of Si nanoparticles during lithiation as well as the enlarged contact area between active materials and conducting agent attributed to the morphological characteristics of its 1D nanostructure. Actually, lithium-air battery can be the real replacement of lithium ion secondary battery because of its high theoretical specific energy coming up to 11,140 Wh/kg. So, some of important issues related to the cathode of lithium-air battery will be also dealt with in this presentation.