Tuning the Outward to Inward Swelling in Lithiated Silicon Nanotubes via Surface Oxide Coating

Journal Article · Wed Sep 14 04:00:00 EDT 2016 · Nano Letters

DOI:https://doi.org/10.1021/acs.nanolett.6b02581· OSTI ID:1340871

Wang, Jiangwei; Luo, Hao; Liu, Yang; He, Yang; Fan, Feifei; Zhang, Ze; Mao, Scott X.; Wang, Chongmin; Zhu, Ting

The electrochemically-induced mechanical degradation hinders the application of Si anodes in advanced lithium-ion batteries. Hollow structures and surface coatings have been often used to mitigate the degradation of Si-based anodes. However, the structural change and degradation mechanism during lithiation/delithiation of hollow Si structures with coatings remain unclear. Here, we combine in situ TEM experiment and chemomechanical modeling to study the electrochemically induced swelling of amorphous-Si (a-Si) nanotubes with different thicknesses of surface SiOx layers. Surprisingly, we find that no inward expansion occurs at the inner surface during lithiation of a-Si nanotubes with native oxides. In contrast, inward expansion can be induced by increasing the thickness of SiOx on the outer surface. Moreover, both the sandwich lithiation mechanism and two-stage lithiation process in a-Si nanotubes remain unchanged with the increasing thickness of surface coatings. Our chemomechanical modeling reveals the mechanical confinement effects in lithiated a-Si nanotubes with and without SiOx coatings. This work not only provides insights into the degradation of nanotube anodes with surface coatings, but also sheds light onto the optimal design of hollow anodes for high-performance lithium-ion batteries.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1340871
• Report Number(s): PNNL-SA-120527; 48379; KP1704020
• Journal Information: Nano Letters, Journal Name: Nano Letters Journal Issue: 9 Vol. 16; ISSN 1530-6984
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory