Li+-Ion Dynamics in β-Li3PS4 Observed by NMR: Local Hopping and Long-Range Transport

While still premature as an energy storage technology, bulk solid-state batteries are attracting much attention in the academic and industrial communities lately. In particular, layered lithium metal oxides and lithium thiophosphates hold promise as cathode materials and superionic solid electrolytes, respectively. However, interfacial side reactions between the individual components during battery operation usually result in accelerated performance degradation. Hence, effective surface coatings are required to mitigate or ideally prevent detrimental reactions from occurring and having an impact on the cyclability. In the present work, we examine how surface carbonates incorporated into the sol–gel-derived LiNbO3 protective coating on NCM622 [Li1+x(Ni0.6Co0.2Mn0.2)1–xO2] cathode material affect the efficiency and rate capability of pellet-stack solid-state battery cells with β-Li3PS4 or argyrodite Li6PS5Cl solid electrolyte and a Li4Ti5O12 anode. Our research data indicate that a hybrid coating may in fact be beneficial to the kinetics and the cycling performance strongly depends on the solid electrolyte used.

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“…S3. Refined lattice parameters are given in Tables S2 and S3 and are in good agreement with literature data 7,49,50 .…”

Section: Methodssupporting

confidence: 82%

Effect of surface carbonates on the cyclability of LiNbO3-coated NCM622 in all-solid-state batteries with lithium thiophosphate electrolytes

Kim

Strauss

Bartsch

et al. 2021

Sci Rep

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“…The energetics of the lithium diffusion (activation energies) was estimated/ranked based on one‐particle‐potential formalism applying normalized negative nuclear densities. [ 36–38 ]…”

Section: Methodsmentioning

confidence: 99%

Engineering the Site‐Disorder and Lithium Distribution in the Lithium Superionic Argyrodite Li₆PS₅Br

Gautam

Sadowski

Ghidiu

et al. 2020

Advanced Energy Materials

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Lithium argyrodite superionic conductors, of the form Li6PS5X (X = Cl, Br, and I), have shown great promise as electrolytes for all‐solid‐state batteries because of their high ionic conductivity and processability. The ionic conductivity of these materials is highly influenced by the structural disorder of S2−/X− anions; however, it is unclear if and how this affects the Li distribution and how it relates to transport, which is critical for improving conductivities. Here it is shown that the site‐disorder once thought to be inherent to given compositions can be carefully controlled in Li6PS5Br by tuning synthesis conditions. The site‐disorder increases with temperature and can be “frozen” in. Neutron diffraction shows this phenomenon to affect the Li+ substructure by decreasing the jump distance between so‐called “cages” of clustered Li+ ions; expansion of these cages makes a more interconnected pathway for Li+ diffusion, thereby increasing ionic conductivity. Additionally, ab initio molecular dynamics simulations provide Li+ diffusion coefficients and time‐averaged radial distribution functions as a function of the site‐disorder, corroborating the experimental results on Li+ distribution and transport. These approaches of modulating the Li+ substructure can be considered essential for the design and optimization of argyrodites and may be extended to other lithium superionic conductors.

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“…Here, the increase in Li vacancy content is demonstrated through the Haven ratio, H R = D */ D σ , in Figure b where D * is the self‐diffusivity of the mobile ions measured via PFG and D σ is defined by rescaling the ionic conductivity measured by EIS, σ Li , into diffusivity via the Nernst–Einstein equation (see SI for details):

true D^{σ} = σ_{normalL normali} \frac{k_{B} T}{c q^{2}}

…”

Section: Figurementioning

confidence: 99%

Boosting Solid‐State Diffusivity and Conductivity in Lithium Superionic Argyrodites by Halide Substitution

et al. 2019

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Developing high-performance all-solid-state batteries is contingent on finding solid electrolyte materials with high ionic conductivity and ductility.Here we report new halide-rich solid solution phases in the argyrodite Li 6 PS 5 Cl family, Li 6Àx PS 5Àx Cl 1+x ,a nd combine electrochemical impedance spectroscopy, neutron diffraction, and 7 Li NMR MAS and PFG spectroscopytoshow that increasing the Cl À /S 2À ratio has as ystematic, and remarkable impact on Li-ion diffusivity in the lattice.T he phase at the limit of the solid solution regime, Li 5.5 PS 4.5 Cl 1.5 ,e xhibits ac old-pressed conductivity of 9.4 AE 0.1 mS cm À1 at 298 K( and 12.0 AE 0.2 mS cm À1 on sintering)almost four-fold greater than Li 6 PS 5 Cl under identical processing conditions and comparable to metastable superionic Li 7 P 3 S 11 .W eakened interactions between the mobile Li-ions and surrounding framework anions incurred by substitution of divalent S 2À for monovalent Cl À play amajor role in enhancing Li + -ion diffusivity,a long with increased site disorder and ahigher lithium vacancy population. Figure 5. a) 7 Li MAS NMR for Li 6Àx PS 5Àx Cl 1+x (x = 0, 0.25, 0.375, 0.5) b) correlation of the activation energies from both techniques with the 7 Li isotropic chemical shift and the Haven ratio for all values of x under study.

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Li⁺-Ion Dynamics in β-Li₃PS₄ Observed by NMR: Local Hopping and Long-Range Transport

Cited by 95 publications

References 38 publications

Effect of surface carbonates on the cyclability of LiNbO3-coated NCM622 in all-solid-state batteries with lithium thiophosphate electrolytes

Effect of surface carbonates on the cyclability of LiNbO3-coated NCM622 in all-solid-state batteries with lithium thiophosphate electrolytes

Engineering the Site‐Disorder and Lithium Distribution in the Lithium Superionic Argyrodite Li₆PS₅Br

Boosting Solid‐State Diffusivity and Conductivity in Lithium Superionic Argyrodites by Halide Substitution

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Li+-Ion Dynamics in β-Li3PS4 Observed by NMR: Local Hopping and Long-Range Transport

Cited by 95 publications

References 38 publications

Effect of surface carbonates on the cyclability of LiNbO3-coated NCM622 in all-solid-state batteries with lithium thiophosphate electrolytes

Effect of surface carbonates on the cyclability of LiNbO3-coated NCM622 in all-solid-state batteries with lithium thiophosphate electrolytes

Engineering the Site‐Disorder and Lithium Distribution in the Lithium Superionic Argyrodite Li6PS5Br

Boosting Solid‐State Diffusivity and Conductivity in Lithium Superionic Argyrodites by Halide Substitution

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Product

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Li⁺-Ion Dynamics in β-Li₃PS₄ Observed by NMR: Local Hopping and Long-Range Transport

Engineering the Site‐Disorder and Lithium Distribution in the Lithium Superionic Argyrodite Li₆PS₅Br