Silicon has been regarded as an optimized anode material of LIBs^1-4 due to its low discharge potential and high specific capacity. Challenges from the huge volume change during the alloying reaction of silicon with lithium still obstacle the application of silicon anode, since the huge volume change causes particle pulverization, electrode disintegration and the solid electrolyte interphase (SEI) film ceaseless growth.  Although some nano-structured silicon anode materials, such as hollow nanospheres, silicon core-hollow carbon shell nanocomposites, 1D hollow silicon nanotubes, showed the improved cycle performance. However, the ceaseless growth of SEI film is still absence of evidence. In this work, we report a facile approach to prepare silicon foam with hollow structure with a chemical vapor deposition (CVD). With the built-in space, this silicon foam presents remarkable capacity retention and fairly high coulombic efficiency. The method combining the electrochemical impedance spectroscopy with differential scanning calorimetry (DSC) to elucidate the SEI stability was developed, which confirm that silicon foam have more stabilized interface.

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