Nanotubular structured Si-based multicomponent anodes for high-performance lithium-ion batteries with controllable pore size via coaxial electro-spinning

We demonstrate a simple but straightforward process for the synthesis of nanotube-type Si-based multicomponents by combining a coaxial electrospinning technique and subsequent metallothermic reduction reaction. Si-based multicomponent anodes consisting of Si, alumina and titanium silicide show several advantages for high-performance lithium-ion batteries. Alumina and titanium silicide, which have high mechanical properties, act as an effective buffer layer for the large volume change of Si, resulting in outstanding volume suppression behavior (volume expansion of only 14%). Moreover, electrically conductive titanium silicide layers located at the inner and outer layers of a Si nanotube exhibit a high initial coulombic efficiency of 88.5% and an extraordinary rate capability. Nanotubular structured Si-based multicomponents with mechanically and electrically improved components can be used as a promising alternative to conventional graphite anode materials. This synthetic route can be extended to other high capacity lithium-ion battery anode materials.