Stoichiometrically driven disorder and local diffusion in NMC cathodes
Open Access
- 12 April 2021
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of Materials Chemistry A
- Vol. 9 (16), 10477-10486
- https://doi.org/10.1039/d1ta01639c
Abstract
Major structural differences in lithium nickel manganese cobalt oxides (NMC) prepared under identical conditions have been uncovered using neutron powder diffraction. Sample NMC-622 was obtained as a single R3 @#x0305;m crystal structure with little defects, whereas NMC-811 showed significant Li deficiency and NMC-433 formed three distinct phases; ordered R3 @#x0305;m, disordered R3 @#x0305;m and a C2/m phase. Local diffusion behaviour was also studied by muon spin relaxation (µSR). It was observed that single phase R3 @#x0305;m NMC-622 showed a higher lithium diffusion coefficient (4.4 × 10−11 cm2 s−1) compared to lithium deficient NMC-811 (2.9 × 10−11 cm2 s−1), or the highly disordered NMC-433 (3.4 × 10−11 cm2 s−1). Furthermore, activation energies for the Li diffusion process were estimated to be 58 meV, 61 meV and 28 meV for NMC-811, NMC-622 and NMC-433, respectively.Keywords
Funding Information
- Science and Technology Facilities Council (RB1810750)
- Engineering and Physical Sciences Research Council (EP/R023662/1)
This publication has 48 references indexed in Scilit:
- Formation of Layered–Layered Composites in the Li–Co–Mn Oxide Pseudoternary System during Slow CoolingChemistry of Materials, 2013
- Minimization of the cation mixing in Li1+x(NMC)1−xO2 as cathode materialJournal of Power Sources, 2010
- Li Diffusion inProbed by Muon-Spin SpectroscopyPhysical Review Letters, 2009
- Magnetism and lithium diffusion in LixCoO2 by a muon-spin rotation and relaxation (μ+SR) techniqueJournal of Power Sources, 2007
- Li2MnO3-stabilized LiMO2 (M = Mn, Ni, Co) electrodes for lithium-ion batteriesJournal of Materials Chemistry, 2007
- Atomic resolution of lithium ions in LiCoO2Nature Materials, 2003
- An overview of the Li(Ni,M)O2 systems: syntheses, structures and propertiesElectrochimica Acta, 1999
- Lithium Diffusion in Layered Li[sub x]CoO[sub 2]Electrochemical and Solid-State Letters, 1999
- Optimization of the Composition of the Li1 − z Ni1 + z O 2 Electrode Materials: Structural, Magnetic, and Electrochemical StudiesJournal of the Electrochemical Society, 1996
- Solid‐State Redox Reactions of LiNi1 / 2Co1 / 2 O 2 ( R 3̄m ) for 4 Volt Secondary Lithium CellsJournal of the Electrochemical Society, 1994