Three-dimensional atomic-scale observation of structural evolution of cathode material in a working all-solid-state battery.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30131492.
- Also identified by DOI 10.1038/s41467-018-05833-x and PMC identifier 6104093.
- 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
Most technologically important electrode materials for lithium-ion batteries are essentially lithium ions plus a transition-metal oxide framework. However, their atomic and electronic structure evolution during electrochemical cycling remains poorly understood. Here we report the in situ observation of the three-dimensional structural evolution of the transition-metal oxide framework in an all-solid-state battery. The in situ studies LiNi<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub> from various zone axes reveal the evolution of both atomic and electronic structures during delithiation, which is found due to the migration of oxygen and transition-metal ions. Ordered to disordered structural transition proceeds along the <100>, <110>, <111> directions and inhomogeneous structural evolution along the <112> direction. Uneven extraction of lithium ions leads to localized migration of transition-metal ions and formation of antiphase boundaries. Dislocations facilitate transition-metal ions migration as well. Theoretical calculations suggest that doping of lower valence-state cations effectively stabilize the structure during delithiation and inhibit the formation of boundaries.