Operando real-space imaging of a structural phase transformation in the high-voltage electrode Li<sub>x</sub>Ni<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39738022.
- Also identified by DOI 10.1038/s41467-024-55010-6 and PMC identifier 11685944.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Discontinuous solid-solid phase transformations play a pivotal role in determining the properties of rechargeable battery electrodes. By leveraging operando Bragg Coherent Diffractive Imaging (BCDI), we investigate the discontinuous phase transformation in Li<sub>x</sub>Ni<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub> within an operational Li metal coin cell. Throughout Li-intercalation, we directly observe the nucleation and growth of the Li-rich phase within the initially charged Li-poor phase in a 500 nm particle. Supported by the microelasticity model, the operando imaging unveils an evolution from a curved coherent to a planar semi-coherent interface driven by dislocation dynamics. Our data indicates negligible kinetic limitations from interface propagation impacting the transformation kinetics, even at a discharge rate of C/2 (80 mA/g). This study highlights BCDI's capability to decode complex operando diffraction data, offering exciting opportunities to study nanoscale phase transformations with various stimuli.