Structural evolution of disordered LiCo(1/3)Fe(1/3)Mn(1/3)PO(4)in lithium batteries uncovered
Journal article, 2020

In this study we address the Li-ion de-insertion/insertion mechanisms from/into the lattice of the mixed olivine LiCo1/3Fe1/3Mn1/3PO4(LCFMP). This mechanism is driven by a subtle interplay of structural, electronic and thermodynamic features. We aim at dissecting this complex landscape that is tightly connected to the long-term electrochemical performance of this material as a positive electrode in lithium-ion cells. To this end, we report advanced structural characterization, based onex situsynchrotronradiation diffraction on samples at different lithium contents. We couple this analysis with first-principles simulations, for a directvis-a-viscomparison. Our results show that (1) the mixing of the three transition-metal (TM) cations in the olivine lattice leads to a solid solution, providing the olivine lattice with the necessary flexibility to retain its single-phase structure during cell operation; (2) the electronic features of the three TMs are responsible for the observed electrochemical performance; (3) the de-lithiation of the olivine lattice is a thermodynamically driven process. Last but not least, our integrated experimental and theoretical results reveal the subtle features behind the formation of antisite defects that selectively involve Li-Co couples. In conclusion, our study provides the necessary scientific foundations to understand the structure-property-function relationships in LCFMP olivines, paving the way for further development and optimization of this material for application in Li-ion batteries.

Author

Ana Belen Munoz-Garcia

University of Naples Federico II

Bernardino Tirri

University of Naples Federico II

Isaac Capone

University of Oxford

Aleksandar Matic

Chalmers, Physics, Materials Physics

Michele Pavone

University of Naples Federico II

Sergio Brutti

Sapienza University of Rome

UOS Sapienza

Journal of Materials Chemistry A

2050-7488 (ISSN)

Vol. 8 37 19641-19653

Subject Categories

Inorganic Chemistry

Materials Chemistry

Other Materials Engineering

DOI

10.1039/d0ta05350c

More information

Latest update

11/17/2020