Image based modelling of microstructural heterogeneity in LiFePO4 electrodes for Li-ion batteries

JOURNAL OF POWER SOURCES

卷:247

Article

Cooper, S. J.¹  Eastwood, D. S.^2,3  Gelb, J.⁴  Damblanc, G.⁵  Brett, D. J. L.⁶  Bradley, R. S.²  Withers, P. J.^2,3  Lee, P. D.^2,3  Marquis, A. J.⁷  Brandon, N. P.⁸  Shearing, P. R.⁶ 

[1] Univ London Imperial Coll Sci Technol & Med, Dept Mat, London SW7 2AZ, England

[2] Univ Manchester, Sch Mat, Manchester Xray Imaging Facil, Manchester M1 7HS, Lancs, England

[3] Rutherford Appleton Lab, Didcot OX11 0FA, Oxon, England

[4] Xradia Inc, Pleasanton, CA 94588 USA

[5] CD Adapco, London W6 7NL, England

[6] UCL, Dept Chem Engn, London WC1E 7JE, England

[7] Univ London Imperial Coll Sci Technol & Med, Dept Mech Engn, London SW7 2AZ, England

[8] Univ London Imperial Coll Sci Technol & Med, Dept Earth Sci & Engn, London SW7 2AZ, England

关键词: Li-ion battery;    X-ray tomography;    Lithium iron phosphate;    Tortuosity;    Imaged based modelling;   

DOI  :  10.1016/j.jpowsour.2013.04.156

来源: Elsevier

【 摘 要 】

Battery and fuel cell simulations commonly assume that electrodes are macro-homogeneous and isotropic. These simulations have been used to successfully model performance, but give little insight into predicting failure. In Li-ion battery electrodes, it is understood that local tortuosity impacts charging rates, which may cause increased degradation. This report describes a novel approach to quantifying tortuosity based on a heat transfer analogy applied to X-ray microscopy data of a commercially available LiFePO4 electrode. This combination of X-ray imaging and image-based simulation reveals the microscopic performance of the electrode; notably, the tortuosity was observed to vary significantly depending on the direction considered, which suggests that tortuosity might best be quantified using vectors rather than scalars. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.

【 授权许可】

Free