The Si/Ag2Si/Ag particles with the enhanced mechanical contact as anode material for lithium ion batteries

•Si/Ag2Si/Ag composite particles were successfully fabricated by a facile method.•Silver nanoparticles attached to silicon improve overall conductivity.•The alloyed interface can enhance the mechanical contact between silicon and silver particles.•Si/Ag2Si/Ag electrode exhibits excellent electrochemical properties. The silver-deposited silicon (Si/Ag) is a successful strategy to enhance the conductivity of Si anode material. However, Ag nanoparticles can be separated from the Si due to the huge volume variation, which causes the deterioration of cycling performance. In this research, we propose a facile method of synthesizing Si/Ag particles with alloyed interface (Si/Ag2Si/Ag) by rapid thermal process to enhance the mechanical contact between Si and Ag. The reversible capacity of Si/Ag2Si/Ag still remains 1138 mAh g−1 over 100 cycles at 0.5 C (1 C = 4.2 A g−1), which is 267 mAh g−1 higher than of Si/Ag. Besides, Si/Ag2Si/Ag holds the reversible capacity of 849 mAh g−1 at 2 C.