Synthesis and Surface Engineering of Composite Anodes by Coating Thin-Layer Silicon on Carbon Cloth for Lithium Storage with High Stability and Performance

Silicon-flexible carbon composites can achieve binder-free application and solve the problem of silicon expansion during cycles. The effective loading and dispersion of silicon onto carbon play an important role in improving the performance of anode materials. Herein, surface engineering of the hole-opening process was successfully achieved before the deposition of silicon. This resulted in fine holes on the carbon cloth, increasing the specific surface area to provide abundant confined spaces for dispersing nano-silicon. A composite structure was formed and structurally optimized by depositing an ultra-thin silicon layer in the holes of mesoporous carbon fiber cloth (DTSi/CC), improving the conductivity of the material, increasing the migration rate of lithium ions, and inhibiting the volume expansion of the anode material during the cycles. At 100 mA g–1, the fabricated half-cells achieved a reversible capacity of 1457 mA h g–1 and retained 70.9% initial capacity after 100 cycles. Even when the current density was increased to 1.0 A g–1, they boasted a capacity of 1037 mA h g–1 and had 76.8% capacity retention after 500 cycles. Free of binders and conductive additives, the DTSi/CC composite was directly used as the anode, exhibiting superior properties with high reversible specific capacity, excellent cyclic performance, and good rate capability. This study provides a straightforward, effective route to obtain high-performance silicon-based anode materials for lithium-ion batteries.