Doped-Si–Ag composite electrodes for Li-ion batteries

• Investigation of electrochemical performance of pure Si, n-type doped Si (orientation< 100 >), and silver coated n-type doped-Si electrodes.
• The electroless deposition of silver coated doped Si has a lower impedance and higher cyclability compared with those of pure Si and doped-Si.
• Electroless deposition of silver on silicon helped in reducing the charge transfer resistance.

An experimental study is carried out of the electrochemical characteristics of electrodes made from pure silicon (Si), doped-silicon (doped-Si) particles and doped-silicon–silver (doped-Si–Ag) composite particles. Doped-Si particles of 10–20 μm are obtained by mechanically crushing the silicon wafers, followed by sieving, and the doped-Si–Ag composite particles was prepared by self-selective electroless deposition. The Ag coating on doped-Si provides improved overall electrical conductivity that enables a better charge transfer. Measurements show that the doped-Si–Ag composite anode give the best electrochemical performance, with the lowest impedance and improved cyclability, and this is followed by the electrodes of doped-Si and pure Si. Moreover, the composite electrode has a stable discharge capacity of 1300 mAhrg− 1 for more than 100 cycles, which is attributed to a good electrical integrity, while the pure and doped-Si electrodes degraded in less than 40 cycles.