Classical molecular dynamics and quantum ab-initio studies on lithium-intercalation in interconnected hollow spherical nano-spheres of amorphous silicon

JOURNAL OF ALLOYS AND COMPOUNDS

卷:665

Article

Bhowmik, A.¹  Malik, R.²  Prakash, S.³  Sarkar, T.⁴  Bharadwaj, M. D.⁴  Aich, S.²  Ghosh, S.² 

[1] Tech Univ Denmark, Dept Energy Convers & Storage, Atom Scale Modelling & Mat, Rios Campus,Frederiksborgvej 399, DK-4000 Roskilde, Denmark

[2] Indian Inst Technol, Dept Met & Mat Engn, Kharagpur 721302, W Bengal, India

[3] Def Met Res Lab, Po Kanchanbagh, Hyderabad 500258, Andhra Pradesh, India

[4] Ctr Study Sci Technol & Policy, Bangalore 560094, Karnataka, India

关键词: Amorphous;    Nano-glass;    Atomic density;    Lithium intercalation;    Cyclability;   

DOI  :  10.1016/j.jallcom.2015.10.274

来源: Elsevier

【 摘 要 】

A high concentration of lithium, corresponding to charge capacity of similar to 4200 mAh/g, can be intercalated in silicon. Unfortunately, due to high intercalation strain leading to fracture and consequent poor cyclability, silicon cannot be used as anode in lithium ion batteries. But recently interconnected hollow nano-spheres of amorphous silicon have been found to exhibit high cyclability. The absence of fracture upon lithiation and the high cyclability has been attributed to reduction in intercalation stress due to hollow spherical geometry of the silicon nano-particles. The present work argues that the hollow spherical geometry alone cannot ensure the absence of fracture. Using classical molecular dynamics and density functional theory based simulations; satisfactory explanation to the absence of fracture has been explored at the atomic scale. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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