Architecture and performance of Si/C microspheres assembled by nano-Si via electro-spray technology as stability-enhanced anodes for lithium-ion batteries

• Construct carbon protective shell to alleviate huge volume changes of Si. • Robust carbon framework can effectively maintains the structure integrity. • Carbon buffer layer can offer rich e-/ion channels to improve reaction kinetics. • The SCM electrode exhibited excellent electrochemical performance. Si-based anodes have revealed the potential as the next generation of lithium ion battery anode material, whereas the poor conductivity and huge volume changes during (de)lithiation process of silicon still limit their practical application. Herein, the Si/nitrogen doped carbon layer/carbon framework microspheres (SCM) are designed by nano-Si via electro-spray technology as anodes for lithium ion batteries. It has been found that the SCM consists of individual carbon-coated nano-Si primary particles linked by PAN framework, in which the carbon buffer layer can further absorb the stress of volume changes during charge/discharge process, and the carbon framework carbon framework not only provides fast diffusion path of electron, but also effectively reduces the consumption of electrolyte. Therefore, the initial columbic efficiency (ICE) of SCM anode can reach as high as 72%, and the SCM anode also shows a high specific capacity of 1192 mAh g −1 at 0.2 A g −1 and keeps a reversible capacity of 746 mAh g −1 after 200 cycles, demonstrating the as-designed SCM possesses an high ICE and a good electrochemical performance. This strategy provides a significant inspiration for fabricating high-performance Si/C anode materials of lithium-ion battery.