Recent Advances in the Structural Design of Silicon/Carbon Anodes for Lithium Ion Batteries: A Review

As the capacity of lithium-ion batteries (LIBs) with commercial graphite anodes is gradually approaching the theoretical capacity of carbon, the development of silicon-based anodes, with higher energy density, has attracted great attention. However, the large volume variation during its lithiation/de-lithiation tends to lead to capacity decay and poor cycling performance. While rationally designed silicon/carbon (Si/C) anodes can exhibit higher specific capacity by virtue of silicon and high electrical conductivity and volume expansion suppression by virtue of carbon, they still show poor cycling performance with low initial coulombic efficiency. This review focuses on three strategies for structural design and optimization of Si/C anodes, i.e., carbon-coated structure, embedded structure and hollow structure, based on the recent researches into Si/Canodes and provides deeper insights into the problems that remain to be addressed.