S C
IE N
T IF
IC H
IG H
LI G
H T
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Y N
A N
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8 3 I H I G H L I G H T S 2 0 2 1
Fig. 65: a) Li concentration as a function of depth and time. b-d) Heterogeneity measured by the Normalised Absolute Averaged Deviation,
1 z=t |x(z)
reduced in the model, and a homogeneous Li distribution over the whole stage 1 to stage 2 transition was obtained, in agreement with the experiment.
In conclusion, the Li distribution across the thickness of a graphite anode was successfully measured in operando
conditions and a porous electrode model was validated at the microscale. At low concentrations, the predicted successive homogenous/heterogeneous Li distribution was evidenced. However, a homogeneous stage 1 to stage 2 transition was observed, probably due to a suppressed deintercalation process in the high concentration range.
PRINCIPAL PUBLICATION AND AUTHORS
Combining operando X-ray experiments and modelling to understand the heterogeneous lithiation of graphite electrodes, S. Tardif (a), N. Dufour (b), J.-F. Colin (b), G. Gebel (b), M. Burghammer (c), A. Johannes (c), S. Lyonnard (a), M. Chandesris (b), J. Mater. Chem. A 9, 4281 (2021); https:/doi.org/10.1039/D0TA10735B (a) Department of Physics, Univ. Grenoble Alpes, CEA-IRIG, Grenoble (France) (b) Department of Electricity and Hydrogen for Transport, Univ. Grenoble Alpes, CEA- LITEN, Grenoble (France) (c) ESRF
REFERENCES
[1] N. Dufour et al., Electrochim. Acta 272, 97-107 (2018). [2] M.Z. Bazant, Faraday Discuss. 199, 423-463 (2017).
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