화학공학소재연구정보센터
Electrochimica Acta, Vol.129, 373-378, 2014
A facile method for determining a suitable voltage window for an amorphous Li12Si7 anode
We report the first attempt to retard the pulverization of an amorphous Li12Si7 anode by controlling the working voltage window. The suitable working voltage window for the amorphous Li12Si7 anode was determined to be 0.11 -0.7V by analyzing the change in the charge transfer resistance using electrochemical impedance spectroscopy. After 100 cycles, the capacity retention of the Li12Si7 electrode cycled at 0.11 -0.7V increased to 57.6% from the 18.2% capacity retention obtained for the electrode cycled at 0.02- 2.0 V, representing more than a 2-fold enhancement. SEM observations displayed the limited pulverization and fracture for the electrode cycled at 0.11-0.7 V, which is the most important reason for the improved cycling stability. The methodology presented in this work can be extended to other electrode materials for Li-ion batteries that undergo large volume changes during lithiation/delithiation. (C) 2014 Elsevier Ltd. All rights reserved.