||Effect of Mechanical Pre-Lithiation on Electrochemical Performance of Silicon Negative Electrode for Lithium-Ion Batteries
Domi, Yasuhiro ,
Usui, Hiroyuki ,
Iwanari, DaichiSakaguchi, Hiroki
Journal of the Electrochemical Society
A1654 , 2017-06-02 , The Electrochemical Society
The effect of pre-lithiation on the electrochemical performance of Si negative electrodes for lithium-ion batteries was studied. A pre-volume-expansion of Si induced by the pre-lithiation is expected to decrease the relative change in volume of Si during chargedischarge reactions. Suppression of change in volume of Si should improve the cycle performance, the Coulombic efficiency, and so on. When the mechanically pre-doped Li was extracted from Li-Si alloy during the first cycle, an alloy electrode exhibited the poor cycle performance just like a Si-alone electrode. On the other hand, the Li1.00Si electrode exhibited the improved cycle performance and higher Coulombic efficiency under the discharge cut-off potential of 0.7 and 0.5 V, espectively. The electrode also showed 1.5 times longer cycle life compared to the Si-alone lectrode when the charge capacity and the cut-off potential were limited. These results demonstrated that the appropriate mechanical pre-lithiation helps to improve the poor electrochemical performance of the Si negative electrodes.