Electrospraying Si/SiO _x /C and Sn/C nanosphere arrays on carbon cloth for high-performance flexible lithium-ion batteries

Exploring electrode materials with larger capacity, higher power density and longer cycle life was critical for developing advanced flexible lithium-ion batteries (LIBs). Herein, we used a controlled two-step method including electrospraying followed with calcination treatment by CVD furnace to design novel electrodes of Si/Si _x /C and Sn/C microrods array consisting of nanospheres on flexible carbon cloth substrate (denoted as Si/Si _x /C@CC, Sn/C@CC). Microrods composed of cumulated nanospheres (the diameter was approximately 120 nm) had a mean diameter of approximately 1.5 µm and a length of around 4.0 µm, distributing uniformly along the entire woven carbon fibers. Both of Si/Si/Si _x /C@CC and Sn/C@CC products were synthesized as binder-free anodes for Li-ion battery with the features of high reversible capacity and excellent cycling. Especially Si/Si _x /C electrode exhibited high specific capacity of about 1750 mA∙h∙g⁻¹ at 0.5 A∙g⁻¹ and excellent cycling ability even after 1050 cycles with a capacity of 1388 mA∙h∙g⁻¹. Highly flexible Si/Si _x /C@CC//LiCoO₂ batteries based on liquid and solid electrolytes were also fabricated, exhibiting high flexibility, excellent electrical stability and potential applications in flexible wearable electronics.