Intertwined network of Si/C nanocables and carbon nanotubes as lithium-ion battery anodes

We demonstrate a new kind of Si-based anode architectures consisting of silicon nanowire/overlapped graphene sheet core-sheath nanocables (SiNW@G) intertwined with carbon nanotubes (CNTs). In such a hybrid structure, the CNTs, mechanically binding SiNW@G nanocables together, act as a buffer matrix to accommodate the volume change of SiNW@G, and overlapped graphene sheets (that is, G sheaths) effectively prevent the direct contact of silicon with the electrolyte during cycling, both of which enable the structural integrity and interfacial stabilization of such hybrid electrodes. Furthermore, the one-dimensional nature of both components affords the creation of a three-dimensional interpenetrating network of lithium ion and electron pathways in the resultant hybrids, thereby enabling efficient transport of both electrons and lithium ions upon charging/discharging. As a result, the hybrids exhibit much-improved lithium storage performance.