Structure solution and refinement of metal-ion battery cathode materials using electron diffraction tomography

Hadermann, Joke; Abakumov, Artem M.

doi:10.1107/s2052520619008291

Cited by 12 publications

(7 citation statements)

References 80 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As a result, electron diffraction conditions in the 3D-ED deviate from kinematic approximation, commonly applied while treating the diffraction data, even for 100-200 nm crystallites from which the 3D-ED data were collected. Nevertheless, the obtained reliability factors are generally considered credible for this method [36,37].…”

Section: Resultsmentioning

confidence: 99%

“…The obtained series of diffraction patterns were treated using PETS and JANA 2006 software [33,40] for the reflection search, cluster analysis, indexing, refinement of the unit cell parameters and orientation matrix and final integration of the reflection intensities. The obtained set of intensities and hkl values was used for the kinematical structure refinement that is assumed to be reasonable approximation as the materials do not contain atomic entities with high scattering power [36].…”

Section: Methodsmentioning

confidence: 99%

“…Another quantitative technique that was successfully applied to anti-site defects evaluation is electron diffraction tomography (EDT) or 3D-electron diffraction (3D-ED) [34]. Electron diffraction is more sensitive to the "light" atoms than PXRD [35], for example, in NMCs the "visibility" of Li cations with electrons is around three times higher, compared to X-rays [36]. Indeed, EDT has already been used successfully for the quantification of Li and TM exchange in polyanion Li-ion battery cathodes [37].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Comprehensive Study of Li+/Ni2+ Disorder in Ni-Rich NMCs Cathodes for Li-Ion Batteries

et al. 2021

Self Cite

View full text Add to dashboard Cite

The layered oxides LiNixMnyCozO2 (NMCs, x + y + z = 1) with high nickel content (x ≥ 0.6, Ni-rich NMCs) are promising high-energy density-positive electrode materials for Li-ion batteries. Their electrochemical properties depend on Li+/Ni2+ cation disordering originating from the proximity of the Li+ and Ni2+ ionic radii. We synthesized a series of the LiNi0.8Mn0.1Co0.1O2 NMC811 adopting two different disordering schemes: Ni for Li substitution at the Li site in the samples finally annealed in air, and close to Ni↔Li antisite disorder in the oxygen-annealed samples. The defect formation scenario was revealed with Rietveld refinement from powder X-ray diffraction data, and then the reliability of semi-quantitative parameters, such as I003/I104 integral intensity ratio and c/(2√6a) ratio of pseudocubic subcell parameters, was verified against the refined defect concentrations. The I003/I104 ratio can serve as a quantitative measure of g(NiLi) only after explicit correction of intensities for preferred orientation. Being normalized by the total scattering power of the unit cell, the I003/I104 ratio depends linearly on g(NiLi) for each disordering scheme. The c/(2√6a) ratio appears to be not reliable and cannot be used for a quantitative estimate of g(NiLi). In turn, the volume of the R3¯m unit cell correlates linearly with g(NiLi), at least for defect concentrations not exceeding 5%. The microscopy techniques such as high-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and electron diffraction tomography (EDT) allow us to study the materials locally, still, there is no proper quantitative approach for comprehensive analysis of defects. In the present work, the TEM-assisted quantitative Li+/Ni2+ disordering analysis with EDT and HAADF-STEM in six Ni-rich NMC samples with various defects content is demonstrated. Noteworthy, while PXRD and EDT methods demonstrate overall defect amounts, HAADF-STEM allows us to quantitatively distinguish regions with various disordering extents. Therefore, the combination of mentioned PXRD and TEM methods gives the full picture of Li+/Ni2+ mixing defects in Ni-rich NMCs.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Comprehensive Study of Li+/Ni2+ Disorder in Ni-Rich NMCs Cathodes for Li-Ion Batteries

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Compared to powder diffraction, electron diffraction tomography (EDT) demonstrates a number of advantages being applied to the Li-ion battery electrode materials 65 . Electron diffraction intensities can be collected ex situ from submicron-sized single crystals of the electrode at different SoCs free of conductive additives and binder interference, and used for the crystal structure solution.…”

Section: Advances In Diffraction Imaging and Spectroscopic Techniquementioning

confidence: 99%

Solid state chemistry for developing better metal-ion batteries

et al. 2020

Self Cite

View full text Add to dashboard Cite

Metal-ion batteries are key enablers in today’s transition from fossil fuels to renewable energy for a better planet with ingeniously designed materials being the technology driver. A central question remains how to wisely manipulate atoms to build attractive structural frameworks of better electrodes and electrolytes for the next generation of batteries. This review explains the underlying chemical principles and discusses progresses made in the rational design of electrodes/solid electrolytes by thoroughly exploiting the interplay between composition, crystal structure and electrochemical properties. We highlight the crucial role of advanced diffraction, imaging and spectroscopic characterization techniques coupled with solid state chemistry approaches for improving functionality of battery materials opening emergent directions for further studies.

show abstract

“…When compared to TEM imaging, electron diffraction can readily distinguish whether extra reflections are due to twinning or due to the formation of the spinel phase [11][12][13]. Furthermore, electron diffraction requires lower beam intensities while still giving access to information at the level of atom coordinates, even of the lithium ions [14][15][16][17][18].…”

Section: Introductionmentioning

confidence: 99%

Determination of Spinel Content in Cycled Li1.2Ni0.13Mn0.54Co0.13O2 Using Three-Dimensional Electron Diffraction and Precession Electron Diffraction

et al. 2021

Self Cite

View full text Add to dashboard Cite

Among lithium battery cathode materials, Li1.2Ni0.13Mn0.54Co0.13O2 (LR-NMC) has a high theoretical capacity, but suffers from voltage and capacity fade during cycling. This is partially ascribed to transition metal cation migration, which involves the local transformation of the honeycomb layered structure to spinel-like nano-domains. Determination of the honeycomb layered/spinel phase ratio from powder X-ray diffraction data is hindered by the nanoscale of the functional material and the domains, diverse types of twinning, stacking faults, and the possible presence of the rock salt phase. Determining the phase ratio from transmission electron microscopy imaging can only be done for thin regions near the surfaces of the crystals, and the intense beam that is needed for imaging induces the same transformation to spinel as cycling does. In this article, it is demonstrated that the low electron dose sufficient for electron diffraction allows the collection of data without inducing a phase transformation. Using calculated electron diffraction patterns, we demonstrate that it is possible to determine the volume ratio of the different phases in the particles using a pair-wise comparison of the intensities of the reflections. Using this method, the volume ratio of spinel structure to honeycomb layered structure is determined for a submicron sized crystal from experimental three-dimensional electron diffraction (3D ED) and precession electron diffraction (PED) data. Both twinning and the possible presence of the rock salt phase are taken into account. After 150 charge–discharge cycles, 4% of the volume in LR-NMC particles was transformed irreversibly from the honeycomb layered structure to the spinel structure. The proposed method would be applicable to other multi-phase materials as well.

show abstract

Structure solution and refinement of metal-ion battery cathode materials using electron diffraction tomography

Cited by 12 publications

References 80 publications

Comprehensive Study of Li+/Ni2+ Disorder in Ni-Rich NMCs Cathodes for Li-Ion Batteries

Comprehensive Study of Li+/Ni2+ Disorder in Ni-Rich NMCs Cathodes for Li-Ion Batteries

Solid state chemistry for developing better metal-ion batteries

Determination of Spinel Content in Cycled Li1.2Ni0.13Mn0.54Co0.13O2 Using Three-Dimensional Electron Diffraction and Precession Electron Diffraction

Contact Info

Product

Resources

About