Nanostructures of silicon anodes in Li-ion batteries

As the application scenarios of lithium-ion batteries expand to many fields including electric vehicles and wearable devices, the energy density of current Li-ion batteries should be improved for satisfying the raising demand. In recent years, various methods have been gradually intensified, in which battery anode materials have received widespread attention. One of the most effective ways for improving battery performance is the use of silicon with different nanostructures, such as structures with different dimensions and different elemental doping, as the anode material, which can effectively improve the stability of solid electrolyte layers, enhance the number of reversible cycles and reversible capacity. This review summarizes the latest advances in silicon nanostructured anodes for lithium-ion batteries including nitrogen-doped carbon-caged silicon nanoparticles, silicon nanotubes made of layered CaSiO3, layered porous silicon encapsulated in carbon nanotube cages, silicon nanoparticles encapsulated in carbon-coated mesoporous silicon shells, and three-dimensional hierarchical porous structures. These nanostructures with excellent electrochemical properties can provide directions for the evolution of high-performance lithium-ion batteries.