Multi-scale 3D investigations of a commercial 18650 Li-ion battery with correlative electron- and X-ray microscopy

JOURNAL OF POWER SOURCES

卷:357

Article

Gelb, Jeff¹  Finegan, Donal P.²  Brett, Dan J. L.²  Shearing, Paul R.² 

[1] Carl Zeiss Xray Microscopy, Pleasanton, CA USA

[2] UCL, Dept Chem Engn, Electrochem Innovat Lab, Torrington Pl, London WC1E 7JE, England

关键词: 18650;    Characterization;    X-ray microscopy;    Scanning-electron microscopy;    Correlative microscopy;    Tortuosity;   

DOI  :  10.1016/j.jpowsour.2017.04.102

来源: Elsevier

【 摘 要 】

In the present study, a commercial 18650 Li-ion cylindrical cell is investigated with non-destructive 3D X-ray microscopy across a range of length scales, beginning with a survey of the entire cell and non-destructively enlarging a smaller section. Active materials are extracted from a disassembled cell and imaging performed using a combination of sub-micron X-ray microscopy and 2D scanning-electron microscopy, which point toward the need for multi-scale analysis in order to accurately characterize the cell. Furthermore, a small section is physically isolated for 3D nano-scale X-ray microscopy, which provides a measurement of porosity and enables the effective diffusivity and 3-dimensional tortuosities to be calculated via computer simulation. Finally, the 3D X-ray microscopy data is loaded into a correlative microscopy environment, where a representative sub-surface region is identified and, subsequently, analyzed using electron microscopy and energy-dispersive X-ray spectroscopy. The results of this study elucidate the microstructural characteristics and potential degradation mechanisms of a commercial NCA battery and, further, establish a technique for extracting the Bruggeman exponent for a real-world microstructure using correlative microscopy. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

Free