Thursday, 23 June 2016
Riverside Center (Hyatt Regency)
With the ever increasing demands on Li-ion batteries with higher energy densities, alternative anode with higher reversible capacity is required to replace the conventional graphite anode. Here, we demonstrate a cost-effective hydrothermal-carbonization approach to prepare the hard carbon coated nano-Si/graphite (HC-nSi/G) composite as a high performance anode for Li-ion batteries. In this hierarchical structured composite, the hard carbon coating layer not only provides an efficient pathway for electron transfer, but also alleviates the volume variation of silicon during charge/discharge processes. The HC-nSi/G composite electrode shows excellent electrochemical performances including a high specific capacity of 878.6 mAh g-1 based on the total weight of composite, good rate performance (398 mAh g-1 at 4C (2.4 mA g-1)) and a decent cycling stability (75.2% capacity retention over 150 cycles at 1.5 mAh cm-2 areal capacity loading), which is promising for practical applications.