Affiliation:
1. Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany
2. Department of Materials Science and Engineering Korea University Seoul 02841 Republic of Korea
3. Department of Materials Royal School of Mines Imperial College London Prince Consort Road London SW7 2BP UK
Abstract
AbstractThrough its capability for 3D mapping of Li at the nanoscale, atom probe tomography (APT) is poised to play a key role in understanding the microstructural degradation of lithium‐ion batteries (LIB) during successive charge‐ and discharge cycles. However, APT application to materials for LIB is plagued by the field induced delithiation (deintercalation) of Li‐ions during the analysis itself that prevents the precise assessment of the Li distribution. Here, we showcase how a thin Cr‐coating, in‐situ formed on APT specimens of NMC811 in the focused‐ion beam (FIB), preserves the sample's integrity and circumvent this deleterious delithiation. Cr‐coated specimens demonstrated remarkable improvements in data quality and virtually eliminated premature specimen failures, allowing for more precise measurements via. improved statistics. Through improved data analysis, we reveal substantial cation fluctuations in commercial grade NMC811, including complete grains of LiMnO. The current methodology stands out for its simplicity and cost‐effectiveness and is a viable approach to prepare battery cathodes and anodes for systematic APT studies.
Funder
European Research Council
Deutsche Forschungsgemeinschaft
Alexander von Humboldt-Stiftung
Subject
Electrochemistry,Electrical and Electronic Engineering,Energy Engineering and Power Technology