Ni-coated Si microchannel plate electrodes in three-dimensional lithium-ion battery anodes

A three-dimensional (3D) anode comprising a Ni-coated Si microchannel plate (Si-MCP) as the matrix and active materials is prepared by photo-assisted electrochemical etching and electroless deposition. The morphology of the Ni-coated Si-MCP electrode is characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Using lithium foils as the counter electrodes, representative half-cells are fabricated and tested. Galvanostatic charge-discharge (C-D) measurements are conducted between 0.05 and 1.5 V and the Ni/Si-MCP anode exhibits a charge capacity of 3520 mAh g^-1 with a coulombic efficiency close to 95.8% in the initial cycle and above 97% in the second cycle. When the C-D current is stepped up by 25 mAh g^-1 every 10 cycles, the capacity always reaches the designed one of 1000 mAh g ^-1 until the current reaches 100 mA g^-1. Based on electrochemical impedance spectroscopy (EIS) data, the mechanism is studied and described.