Nanocrystalline silicon embedded in an alloy matrix as an anode material for high energy density lithium-ion batteries

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>The development of electrode materials with high capacity and good cycling stability is a challenging prerequisite for improving the energy density of lithium-ion batteries. In this work, we synthesize silicon nanoparticles embedded in the inactive Al<SUB>4</SUB>Cu<SUB>9</SUB>, AlFe and TiFeSi<SUB>2</SUB> matrix phases, as an anode material. The silicon alloy material exhibits good high rate performance and delivers a high initial discharge capacity of 1459.3 mAh g<SUP>−1</SUP> with capacity retention of 85.7% after 200 cycles at a current density of 300 mA g<SUP>−1</SUP>. The superior cycling performance of the silicon alloy compared to that of micro-sized pure silicon can be attributed to the unique structure of the alloy material. Here, the nano-sized silicon particles reduce the ionic diffusion path length and minimize volume expansion during lithiation, while the inactive matrix phases accommodate volume changes during repeated cycling and provide a continuous electronic conduction pathway to the silicon nanoparticles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Si alloy comprising Si nanoparticles embedded in the inert matrix is synthesized. </LI> <LI> It delivers a high initial discharge capacity with good cycling stability. </LI> <LI> As compared to pure Si, the Si alloy material shows superior cycling performance. </LI> <LI> Si alloy can be a promising anode material for high performance lithium-ion battery. </LI> </UL> </P>