Electrochemical Performance of Sn/SnO/Ni3Sn Composite Anodes for Lithium-Ion Batteries.

We have synthesized a novel composite material Sn/SnO/Ni₃Sn via galvanic replacement reaction between Sn and Ni ions in triethylene glycol medium and at high temperature. The reaction time affected structure, particle size, and composition of Sn/SnO/Ni₃Sn composites, which were analyzed by high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The active component (Sn) reacts with Li ions while inactive component (Ni) acts as a metal framework to support the electrochemically active Sn, a buffer to reduce volume change during cycling, and the electron conductor. Among electrodes, the Sn/SnO/Ni₃Sn-6h electrode demonstrated stable cycling and reversible capacity of 246 mAh g even after 300 cycles owing to the advantages from the unique hybrid structure.