Si/C hybrid nanostructures for Li-ion anodes: An overview

• The review regards an emerging and very hot area of research.
• Si/C nanomaterials have ideal properties for innovative and improved Li-ion battery anodes.
• The review present an overview of the methodologies proposed in the last decade for Si/C.
• The relationships between properties of Si/C at nanoscale and battery performance are discussed.
• Promising routes for the optimized fabrication of Si/C nanomaterials are reported.

This review article summarizes recent and increasing efforts in the development of novel Li ion cell anode nanomaterials based on the coupling of C with Si. The rationale behind such efforts is based on the fact that the Si–C coupling realizes a favourable combination of the two materials properties, such as the high lithiation capacity of Si and the mechanical and conductive properties of C, making Si/C hybrid nanomaterials the ideal candidates for innovative and improved Li-ion anodes. Together with an overview of the methodologies proposed in the last decade for material preparation, a discussion on relationship between organization at the nanoscale of the hybrid Si/C systems and battery performances is given. An emerging indication is that the enhancement of the batteries efficiency in terms of mass capacity, energy density and cycling stability, resides in the ability to arrange Si/C bi-component nanostructures in pre-defined architectures. Starting from the results obtained so far, this paper aims to indicate some emerging directions and to inspire promising routes to optimize fabrication of Si/C nanomaterials and engineering of Li-ion anodes structures. The use of Si/C hybrid nanostructures could represents a viable and effective solution to the foreseen limits of present lithium ion technology.