Silicon has been investigated as a high-capacity anode material for Lithium ion batteries while the cycle life desired to improve further for practical application. In this study, we adopt artificial solid electrolyte interphase (SEI) layers to improve cycle life by employing surface modification of silicon nanocrystals (Si NCs). silica nanoparticles (SiO2 NPs) were reduced by magnesiothermic reaction to generate oxide coated silicon nanocrystals (Si NCs@SiOx). The hydride terminated Si NCs (H-Si NCs) were produced from Si NCs@SiOx through wet etching process using hydrofluoric acid (HF). Dimethylethoxyvinyl silane-capped Si NCs (DMEVS-Si NCs) were synthesized by using the H-Si NCs via thermal hydrosilylation reaction. The siloxane polymer-encapsulated Si NCs (polymer-Si NCs) were synthesized form DMEVS-Si NCs and methyltrimethoxysilane (MTMS) via hydrolysis-condensation reaction. Silicon anodes were fabricated by mixing the active material (Si NCs@SiOx, H-Si NCs, DMEVS-Si NCs or polymer-Si NCs), polyacrylic acid (PAA), and Super P Li carbon black. The coin-type (2032R) half-cell with the silicon anodes were cycled at a rate of 0.2C between 0.01 and 2.5 V. The case of polymer-NCs showed significantly improved cyclic properties compared to the others due to the siloxane based polymer acting as an artificial SEI layer.