An electrochemical and structural investigation of silicon nanowires as negative electrode for Li-ion batteries

Barbara Laik (1) , Diane Ung (1) , Amael Caillard (2) , Costel Sorin Cojocaru (3) , Didier Pribat (2) , Jean Pierre Pereira-Ramos (4)

1 ICMPE - Institut de Chimie et des Matériaux Paris-Est
2 LPICM - Laboratoire de physique des interfaces et des couches minces [Palaiseau]
3 NanoMaDe
4 GESMAT

The electrochemical and structural responses of silicon nanowires deposited by chemical vapor deposition are investigated. Transmission electron microscopy and X-ray diffraction experiments show the electrochemical lithiation of SiNWs is not a quantitative process in good agreement with cycling experiments performed as a function of cycling limits. The SiNWs are not deeply lithiated as revealed by TEM micrographs. Our results suggest the existence of two well-defined lithiation steps, first at ∼0.2 V into amorphous silicon and then into crystalline silicon at ∼0.1 V. Cycling SiNWs above 100 mV avoid the lithiation of c-Si which preserves the silicon 3-D architecture and results in good cycling performances. A stable capacity value of ∼500 mAh g−1 is achieved over at least 50 cycles.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Barbara Laik, Diane Ung, Amael Caillard, Costel Sorin Cojocaru, Didier Pribat, et al.. An electrochemical and structural investigation of silicon nanowires as negative electrode for Li-ion batteries. Journal of Solid State Electrochemistry, 2010, 14 (10), pp.1835--1839. ⟨10.1007/s10008-010-1045-5⟩. ⟨hal-00794043⟩