Three-Dimensional Study of Graphite-Composite Electrode Chemo-Mechanical Response using Digital Volume Correlation
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A custom built reusable cell for in situ lithiation and mechanical deformation studies while in an X-ray tomograph was demonstrated, and the strain and volume changes of a composite graphite anode were computed from 3D X-ray microcomputed tomography data via Digital Volume Correlation (DVC). The test anode was a composite electrode comprised of a porous compliant matrix, graphite as the Li+ host material, 5-μm ZrO2 marker particles for use with DVC, and active carbon black to enhance electrical conductivity. The composite electrodes were hot-pressed to control their porosity, and in turn the mechanical integrity of the resulting material. This composite anode was included in a half-cell and lithiated in situ while in a tomograph, and intermittent 3D data were collected at different lithiation levels up to full gravimetric capacity. Strain measurements by DVC demonstrated relatively uniform expansion of the freestanding electrode with average normal strains in the three directions varying by 20%, while the internal shear strains were found to be negligible. The average experimental strains were about 75% of the theoretical value, as estimated by the rule of mixtures, which implies that ~25% of the normal strains in graphite, due to lithiation, are accommodated by the surrounding matrix.
KeywordsTomography Digital Volume Correlation Composite graphite electrode Lithiation
This work was supported in part by the University of Illinois at Urbana Champaign Interdisciplinary Innovation Initiative (In3) Proposal Award #12027. Joseph Gonzalez also acknowledges that this material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144245. Dimitris A. Antartis and Ioannis Chasiotis acknowledge the support by the Air Force Office for Scientific Research through Grants FA9550-12-1-0209 and FA9550-13-1-0149 with Dr. B.L. Lee as the program monitor.
- 4.Srinivasan V (2008) Batteries for vehicular applications. AIP conference proceedings 1044(1):283–296Google Scholar
- 14.Eastwood DS, Yufit V, Gelb J, Gu A, Bradley RS, Harris SJ, Brett DJL, Brandon NP, Lee PD, Withers PJ, Shearing PR (2014) Lithiation-induced dilation mapping in a lithium-ion battery electrode by 3D X-ray microscopy and digital volume correlation. Adv Energy Mater 4(1e7):1300506CrossRefGoogle Scholar
- 15.Finegan DP, Tudisco E, Scheel M, Robinson JB, Taiwo OO, Eastwood DS, Lee PD, Michiel MD, Bay B, Hall S, Hinds G, Brett DJL, Shearing PR (2016) Quantifying bulk electrode strain and material displacement within lithium batteries via high-speed operando tomography and digital volume correlation. Adv Sci 3(1e11):1500332CrossRefGoogle Scholar
- 30.Sutton MA, Orteu J-J, Schreir H (2009) Image correlation for shape, motion and deformation measurements: basic concepts, theory and applications. Springer, BerlinGoogle Scholar