Amorphous-silicon@silicon oxide/chromium/carbon as an anode for lithium-ion batteries with excellent cyclic stability

作者：Li Mingqi^*; Gu Jingwei; Feng Xiaofang; He Hongyan; Zeng Chunmei

来源：Electrochimica Acta, 2015, 164: 163-170.

DOI：10.1016/j.electacta.2015.02.224

• Silicon oxide
• Composite
• Anode
• Electrochemical performance
• Lithium-ion battery

A new amorphous-Si@SiOx/Cr/carbon (a-Si@SiOx/Cr/C) anode composite for lithium-ion batteries is synthesized, using SiO, chromium powder and graphite as starting materials. X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), scanning electron microscope (SEM) and high resolution transmission electron microscope (HRTEM) are employed to characterize the composition, morphology and microstructure of the composite. Coin-type cells are assembled to investigate the electrochemical behaviors of the as-prepared composites by constant current charge-discharge technique, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results show that chromium facilitates the crush of Si@SiOx and graphite during milling, and thus improves their mutual dispersion in the composite. When cycled at 100 mA g (1), the a-Si@SiOx/Cr/C exhibits a stable discharge capacity of about 810 mAh g (1) (calculated on the mass of a-Si@SiOx/Cr/C) with good capacity retention up to 200 cycles. The improved electrochemical performance is attributed to the reduced particle size of a-Si@SiOx and the synergistic effect of carbon and chromium.

• 出版日期2015-5-1
• 单位西华师范大学