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1.
Phys Chem Chem Phys ; 25(2): 1169-1176, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36519415

RESUMO

Understanding the correlation between ionic motion and crystal structure is crucial for improving solid electrolyte conductivities. Several substitution series in the Li10GeP2S12 structure have shown a favorable impact on the ionic conductivity, e.g. the replacement of P(+V) by Sb(+V) in Li10GeP2S12. However, here the interplay between the structure and ionic motion remains elusive. X-Ray diffraction, high-resolution neutron diffraction, Raman spectroscopy and potentionstatic impedance spectroscopy are employed to explore the impact of Sb(+V) on the Li10GeP2S12 structure. The introduction of antimony elongates the unit cell in the c-direction and increases the M(1)/P(1) and Li(2) polyhedral volume. Over the solid solution range, the Li+ distribution remains similar, an inductive effect seems to be absent and the ionic conductivity is comparable for all compositions. The effect of introducing Sb(+V) in Li10GeP2S12 cannot be corroborated.

2.
Adv Mater ; : e2208698, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284487

RESUMO

A diode requires the combination of p- and n-type semiconductors or at least the defined formation of such areas within a given compound. This is a prerequisite for any IT application, energy conversion technology, and electronic semiconductor devices. Since the discovery of the pnp-switchable compound Ag10 Te4 Br3 in 2009, it is in principle possible to fabricate a diode from a single material without adjusting the semiconduction type by a defined doping level. Often a structural phase transition accompanied by a dynamic change of charge carriers or a charge density wave within certain substructures are responsible for this effect. Unfortunately, the high pnp-switching temperature between 364 and 580 K hinders the application of this phenomenon in convenient devices. This effect is far removed from a suitable operation temperature at ambient conditions. Ag18 Cu3 Te11 Cl3  is a room temperature pnp-switching material and the first single-material position-independent diode. It shows the highest ever reported Seebeck coefficient drop that takes place within a few Kelvin. Combined with its low thermal conductivity, it offers great application potential within an accessible and applicable temperature window. Ag18 Cu3 Te11 Cl3 and pnp-switching materials have the potential for applications and processes where diodes, transistors, or any defined charge separation with junction formation are utilized.

3.
J Phys Chem Lett ; 13(25): 5938-5945, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35731950

RESUMO

We employ terahertz-range temperature-dependent Raman spectroscopy and first-principles lattice dynamical calculations to show that the undoped sodium ion conductors Na3PS4 and isostructural Na3PSe4 both exhibit anharmonic lattice dynamics. The anharmonic effects in the compounds involve coupled host lattice-Na+ ion dynamics that drive the tetragonal-to-cubic phase transition in both cases, but with a qualitative difference in the anharmonic character of the transition. Na3PSe4 shows an almost purely displacive character with the soft modes disappearing in the cubic phase as the change in symmetry shifts these modes to the Raman-inactive Brillouin zone boundary. Na3PS4 instead shows an order-disorder character in the cubic phase, with the soft modes persisting through the phase transition and remaining Raman active in the cubic phase, violating Raman selection rules for that phase. Our findings highlight the important role of coupled host lattice-mobile ion dynamics in vibrational instabilities that are coincident with the exceptional conductivity of these Na+ ion conductors.

4.
J Am Chem Soc ; 144(4): 1795-1812, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35057616

RESUMO

Solid electrolytes are at the heart of future energy storage systems. Li-bearing argyrodites are frontrunners in terms of Li+ ion conductivity. Although many studies have investigated the effect of elemental substitution on ionic conductivity, we still do not fully understand the various origins leading to improved ion dynamics. Here, Li6+xP1-xGexS5I served as an application-oriented model system to study the effect of cation substitution (P5+ vs Ge4+) on Li+ ion dynamics. While Li6PS5I is a rather poor ionic conductor (10-6 S cm-1, 298 K), the Ge-containing samples show specific conductivities on the order of 10-2 S cm-1 (330 K). Replacing P5+ with Ge4+ not only causes S2-/I- anion site disorder but also reveals via neutron diffraction that the Li+ ions do occupy several originally empty sites between the Li rich cages in the argyrodite framework. Here, we used 7Li and 31P NMR to show that this Li+ site disorder has a tremendous effect on both local ion dynamics and long-range Li+ transport. For the Ge-rich samples, NMR revealed several new Li+ exchange processes, which are to be characterized by rather low activation barriers (0.1-0.3 eV). Consequently, in samples with high Ge-contents, the Li+ ions have access to an interconnected network of pathways allowing for rapid exchange processes between the Li cages. By (i) relating the changes of the crystal structure and (ii) measuring the dynamic features as a function of length scale, we were able to rationalize the microscopic origins of fast, long-range ion transport in this class of electrolytes.

5.
ChemSusChem ; 15(4): e202200078, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35099111

RESUMO

Invited for this month's cover is a combined work of the Helmholtz Institute Münster together with the MEET Battery Research Center and the Universities of Münster and Mainz. The cover shows multiple treatment choices for the modification of cathode active materials for lithium-ion batteries. Similar to a car wash program, the treatment will typically result in an improvement of the status quo. However, the best treatment procedure will only become clear if all modification pathways are explored. The Research Article itself is available at 10.1002/cssc.202102220.

6.
ChemSusChem ; 15(4): e202102220, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-34784118

RESUMO

Ni-rich layered oxide cathodes are promising candidates to satisfy the increasing energy demand of lithium-ion batteries for automotive applications. Thermal and cycling stability issues originating from increasing Ni contents are addressed by mitigation strategies such as elemental bulk substitution ("doping") and surface coating. Although both approaches separately benefit the cycling stability, there are only few reports investigating the combination of two of such approaches. Herein, the combination of Zr as common dopant in commercial materials with effective Li2 WO4 and WO3 coatings was investigated with special focus on the impact of different material processing conditions on structural parameters and electrochemical performance in nickel-cobalt-manganese (NCM) || graphite cells. Results indicated that the Zr4+ dopant diffusing to the surface during annealing improved the electrochemical performance compared to samples without additional coatings. This work emphasizes the importance to not only investigate the effect of individual dopants or coatings but also the influences between both.

7.
ACS Mater Lett ; 3(5): 652-657, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34476400

RESUMO

State-of-the-art oxides and sulfides with high Li-ion conductivity and good electrochemical stability are among the most promising candidates for solid-state electrolytes in secondary batteries. Yet emerging halides offer promising alternatives because of their intrinsic low Li+ migration energy barriers, high electrochemical oxidative stability, and beneficial mechanical properties. Mechanochemical synthesis has enabled the characterization of LiAlX4 compounds to be extended and the iodide, LiAlI4, to be synthesized for the first time (monoclinic P21/c, Z = 4; a = 8.0846(1) Å; b = 7.4369(1) Å; c = 14.8890(2) Å; ß = 93.0457(8)°). Of the tetrahaloaluminates, LiAlBr4 exhibited the highest ionic conductivity at room temperature (0.033 mS cm-1), while LiAlCl4 showed a conductivity of 0.17 mS cm-1 at 333 K, coupled with the highest thermal and oxidative stability. Modeling of the diffusion pathways suggests that the Li-ion transport mechanism in each tetrahaloaluminate is closely related and mediated by both halide polarizability and concerted complex anion motions.

8.
Inorg Chem ; 60(24): 18975-18980, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34851091

RESUMO

The lithium argyrodites Li6PS5X (X = Cl, Br, and I) have attracted interest as fast solid ionic conductors for solid-state batteries. Within this class of materials, it has been previously suggested that more polarizable anions and larger substituents should influence the ionic conductivity (e.g., substituting S by Se). Building upon this work, we explore the influence of Sn substitution in lithium argyrodites Li6+xSnxP1-xSe5I in direct comparison to the previously reported Li6+xSnxP1-xS5I series. The (P5+/Sn4+)Se43/4- polyhedral volume, unit cell volume, and lithium coordination tetrahedra Li(48h)-(S/Se)3-I increase with Sn substitution in this new selenide series. Impedance spectroscopy reveals that increasing Sn4+ substitution results in a fivefold improvement in the ionic conductivity when compared to Li6PSe5I. This work provides further understanding of compositional influences for optimizing the ionic conductivity of solid electrolytes.

9.
Chem Sci ; 12(18): 6238-6263, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-34084423

RESUMO

The development of high-performance inorganic solid electrolytes is central to achieving high-energy- density solid-state batteries. Whereas these solid-state materials are often prepared via classic solid-state syntheses, recent efforts in the community have shown that mechanochemical reactions, solution syntheses, microwave syntheses, and various post-synthetic heat treatment routines can drastically affect the structure and microstructure, and with it, the transport properties of the materials. On the one hand, these are important considerations for the upscaling of a materials processing route for industrial applications and industrial production. On the other hand, it shows that the influence of the different syntheses on the materials' properties is neither well understood fundamentally nor broadly internalized well. Here we aim to review the recent efforts on understanding the influence of the synthetic procedure on the synthesis - (micro)structure - transport correlations in superionic conductors. Our aim is to provide the field of solid-state research a direction for future efforts to better understand current materials properties based on synthetic routes, rather than having an overly simplistic idea of any given composition having an intrinsic conductivity. We hope this review will shed light on the underestimated influence of synthesis on the transport properties of solid electrolytes toward the design of syntheses of future solid electrolytes and help guide industrial efforts of known materials.

10.
Angew Chem Int Ed Engl ; 60(33): 17952-17956, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34129261

RESUMO

Given the inherent performance limitations of intercalation-based lithium-ion batteries, solid-state conversion batteries are promising systems for future energy storage. A high specific capacity and natural abundancy make iron disulfide (FeS2 ) a promising cathode-active material. In this work, FeS2 nanoparticles were prepared solvothermally. By adjusting the synthesis conditions, samples with average particle diameters between 10 nm and 35 nm were synthesized. The electrochemical performance was evaluated in solid-state cells with a Li-argyrodite solid electrolyte. While the reduction of FeS2 was found to be irreversible in the initial discharge, a stable cycling of the reduced species was observed subsequently. A positive effect of smaller particle dimensions on FeS2 utilization was identified, which can be attributed to a higher interfacial contact area and shortened diffusion pathways inside the FeS2 particles. These results highlight the general importance of morphological design to exploit the promising theoretical capacity of conversion electrodes in solid-state batteries.

11.
Acc Chem Res ; 54(12): 2717-2728, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34032414

RESUMO

ConspectusAs the world transitions away from fossil energy to green and renewable energy, electrochemical energy storage increasingly becomes a vital component of the mix to conduct this transition. The central goal in developing next-generation batteries is to maximize the gravimetric and volumetric energy density and battery cycle life and improve safety. All solid-state batteries using a solid electrolyte and a lithium metal anode represent one of the most promising technologies that can achieve this goal. Highly conductive solid electrolytes (>10 mS·cm-1) are the key component to remove the safety concerns inherent with flammable organic liquid electrolytes and achieve high energy density by enabling high active material loading. Considering a range of inorganic solid electrolytes that have been developed to date, sulfide solid electrolytes exhibit the highest ionic conductivities, which even surpass those of conventional organic liquid electrolytes. Argyrodite-structured sulfide solid electrolytes are among the most promising materials in this class and are currently the dominantly used solid electrolytes for all-solid-state battery fabrication. Argyrodite solid electrolytes are particularly appealing because of their ultrahigh Li-ion conductivity, quasi-stable solid-electrolyte interphase (SEI) formed with Li metal, and ability to be prepared via scalable solution-assisted synthesis approaches. These factors are all vital for commercial applications.In this Account, we afford an overview of our recent development of several argyrodite superionic conductors, including Li6.6Si0.6Sb0.5S5I (24 mS·cm-1), Li6.6Ge0.6P0.4S5I (18 mS·cm-1), and Li5.5PS4.5Cl1.5 (12 mS·cm-1), and a comprehensive understanding of the origin of the underlying high conductivity, namely, sulfide/halide anion site disorder and Li cation site disorder. A high degree of sulfide/halide anion site disorder (changes in anion distribution) modifies the anionic charge, which in turn strongly influences the lithium distribution. A more inhomogeneous charge distribution in anion-disordered systems generates a spatially diffuse and delocalized lithium density, resulting in faster ionic transport. Lithium cation site disorder generated by increasing Li carrier concentration through aliovalent substitution creates high-energy interstitial sites for Li ion diffusion, which activate concerted ion migration and flatten the energy landscape for Li ion diffusion. This enables high conductivity in Li-rich argyrodite superionic conductors. These concepts are also expected to promote the design of rational new solid electrolytes and fundamental understanding of the structure-ion transport relationships in inorganic ionic conductors.Collectively, a comprehensive and deep understanding of the interphase formation between argyrodite solid electrolytes and cathode active materials/Li metal and the failure mechanism of all-solid-state batteries with argyrodite solid electrolytes will lead to the bottom-up engineering of the cathode/anode-solid electrolyte interfaces, which will accelerate the development of safe, high-energy-density all-solid-state lithium batteries.

12.
J Phys Chem C Nanomater Interfaces ; 125(4): 2306-2317, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33584937

RESUMO

Solid electrolytes are key elements for next-generation energy storage systems. To design powerful electrolytes with high ionic conductivity, we need to improve our understanding of the mechanisms that are at the heart of the rapid ion exchange processes in solids. Such an understanding also requires evaluation and testing of methods not routinely used to characterize ion conductors. Here, the ternary Li4MCh4 system (M = Ge, Sn; Ch = Se, S) provides model compounds to study the applicability of 7Li nuclear magnetic resonance (NMR) spin-alignment echo (SAE) spectroscopy to probe slow Li+ exchange processes. Whereas the exact interpretation of conventional spin-lattice relaxation data depends on models, SAE NMR offers a model-independent, direct access to motional correlation rates. Indeed, the jump rates and activation energies deduced from time-domain relaxometry data perfectly agree with results from 7Li SAE NMR. In particular, long-range Li+ diffusion in polycrystalline Li4SnS4 as seen by NMR in a dynamic range covering 6 orders of magnitude is determined by an activation energy of E a = 0.55 eV and a pre-exponential factor of 3 × 1013 s-1. The variation in E a and 1/τ0 is related to the LiCh4 volume that changes within the four Li4MCh4 compounds studied. The corresponding volume of Li4SnS4 seems to be close to optimum for Li+ diffusivity.

13.
ChemSusChem ; 14(1): 441-448, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32860491

RESUMO

The demand for lithium-ion batteries has risen dramatically over the years. Unfortunately, many of the essential component materials, such as cobalt and lithium, are both costly and of limited abundance. For this reason, the recycling of lithium-ion battery electrodes is crucial to ensuring the availability of such resources and protecting the environment. Herein, a simple and scalable recycling process was developed for the prototypical cathode active material Li1.02 (Ni0.8 Co0.1 Mn0.1 )0.98 O2 (NCM-811). By a combination of thermal decomposition and dissolution steps, spent NCM could be converted into Li2 CO3 and a transition metal oxalate blend, which served as precursors for new NCM. Importantly, it was also possible to individually separate each transition metal during the recycling process, thereby extending the utility of this method to a wide variety of NCM compositions. Each intermediate in the process was investigated by scanning electron microscopy and X-ray diffraction. Additionally, the elemental composition of the recycled NCM-811 was confirmed using inductively coupled plasma optical emission spectroscopy and energy-dispersive X-ray spectroscopy. The electrochemical performance of the recycled NCM-811 exhibited up to 80 % of the initial capacity of pristine NCM-811. The method presented herein serves as an efficient and environmentally benign alternative to existing recycling methods for lithium-ion battery electrode materials.

14.
Angew Chem Int Ed Engl ; 60(12): 6718-6723, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33314609

RESUMO

Owing to high ionic conductivity and good oxidation stability, halide-based solid electrolytes regain interest for application in solid-state batteries. While stability at the cathode interface seems to be given, the stability against the lithium metal anode has not been explored yet. Herein, the formation of a reaction layer between Li3 InCl6 (Li3 YCl6 ) and lithium is studied by sputter deposition of lithium metal and subsequent in situ X-ray photoelectron spectroscopy as well as by impedance spectroscopy. The interface is thermodynamically unstable and results in a continuously growing interphase resistance. Additionally, the interface between Li3 InCl6 and Li6 PS5 Cl is characterized by impedance spectroscopy to discern whether a combined use as cathode electrolyte and separator electrolyte, respectively, might enable long-term stable and low impedance operation. In fact, oxidation stable halide-based lithium superionic conductors cannot be used against Li, but may be promising candidates as cathode electrolytes.

15.
J Am Chem Soc ; 142(50): 21210-21219, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33284622

RESUMO

Strategies to enhance ionic conductivities in solid electrolytes typically focus on the effects of modifying their crystal structures or of tuning mobile-ion stoichiometries. A less-explored approach is to modulate the chemical bonding interactions within a material to promote fast lithium-ion diffusion. Recently, the idea of a solid-electrolyte inductive effect has been proposed, whereby changes in bonding within the solid-electrolyte host framework modify the potential energy landscape for the mobile ions, resulting in an enhanced ionic conductivity. Direct evidence for a solid-electrolyte inductive effect, however, is lacking-in part because of the challenge of quantifying changes in local bonding interactions within a solid-electrolyte host framework. Here, we consider the evidence for a solid-electrolyte inductive effect in the archetypal superionic lithium-ion conductor Li10Ge1-xSnxP2S12. Substituting Ge for Sn weakens the {Ge,Sn}-S bonding interactions and increases the charge density associated with the S2- ions. This charge redistribution modifies the Li+ substructure causing Li+ ions to bind more strongly to the host framework S2- anions, which in turn modulates the Li+ ion potential energy surface, increasing local barriers for Li+ ion diffusion. Each of these effects is consistent with the predictions of the solid-electrolyte inductive effect model. Density functional theory calculations predict that this inductive effect occurs even in the absence of changes to the host framework geometry due to Ge → Sn substitution. These results provide direct evidence in support of a measurable solid-electrolyte inductive effect and demonstrate its application as a practical strategy for tuning ionic conductivities in superionic lithium-ion conductors.

16.
J Am Chem Soc ; 142(43): 18422-18436, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33054192

RESUMO

Fast-ion conductors are critical to the development of solid-state batteries. The effects of mechanochemical synthesis that lead to increased ionic conductivity in an archetypical sodium-ion conductor Na3PS4 are not fully understood. We present here a comprehensive analysis based on diffraction (Bragg and pair distribution function), spectroscopy (impedance, Raman, NMR and INS), and ab initio simulations aimed at elucidating the synthesis-property relationships in Na3PS4. We consolidate previously reported interpretations regarding the local structure of ball-milled samples, underlining the sodium disorder and showing that a local tetragonal framework more accurately describes the structure than the originally proposed cubic one. Through variable-pressure impedance spectroscopy measurements, we report for the first time the activation volume for Na+ migration in Na3PS4, which is ∼30% higher for the ball-milled samples. Moreover, we show that the effect of ball-milling on increasing the ionic conductivity of Na3PS4 to ∼10-4 S/cm can be reproduced by applying external pressure on a sample from conventional high-temperature ceramic synthesis. We conclude that the key effects of mechanochemical synthesis on the properties of solid electrolytes can be analyzed and understood in terms of pressure, strain, and activation volume.

17.
Chem Rev ; 120(15): 7745-7794, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32786669

RESUMO

Developing reversible lithium metal anodes with high rate capability is one of the central aims of current battery research. Lithium metal anodes are not only required for the development of innovative cell concepts such as lithium-air or lithium-sulfur batteries, they can also increase the energy density of batteries with intercalation-type cathodes. The use of solid electrolyte separators is especially promising to develop well-performing lithium metal anodes, because they can act as a mechanical barrier to avoid unwanted dendritic growth of lithium through the cell. However, inhomogeneous electrodeposition and contact loss often hinder the application of a lithium metal anode in solid-state batteries. In this review, we assess the physicochemical concepts that describe the fundamental mechanisms governing lithium metal anode performance in combination with inorganic solid electrolytes. In particular, our discussion of kinetic rate limitations and morphological stability intends to stimulate further progress in the field of lithium metal anodes.

18.
Inorg Chem ; 59(15): 11009-11019, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32673483

RESUMO

The lithium argyrodites Li6PS5X (X = Cl, Br, I) exhibit high lithium-ion conductivities, making them promising candidates for use in solid-state batteries. These solid electrolytes can show considerable substitutional X-/S2- anion disorder, typically correlated with higher lithium-ion conductivities. The atomic-scale effects of this anion site disorder within the host lattice-in particular how lattice disorder modulates the lithium substructure-are not well understood. Here, we characterize the lithium substructure in Li6PS5X as a function of temperature and anion site disorder, using Rietveld refinements against temperature-dependent neutron diffraction data. Analysis of these high-resolution diffraction data reveals an additional lithium position previously unreported for Li6PS5X argyrodites, suggesting that the lithium conduction pathway in these materials differs from the most common model proposed in earlier studies. An analysis of the Li+ positions and their radial distributions reveals that greater inhomogeneity of the local anionic charge, due to X-/S2- site disorder, is associated with more spatially diffuse lithium distributions. This observed coupling of site disorder and lithium distribution provides a possible explanation for the enhanced lithium transport in anion-disordered lithium argyrodites and highlights the complex interplay between the anion configuration and lithium substructure in this family of superionic conductors.

19.
ACS Appl Mater Interfaces ; 11(26): 23244-23253, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31199108

RESUMO

A nondegrading, low-impedance interface between a solid electrolyte and cathode active materials remains a key challenge for the development of functional all-solid-state batteries (ASSBs). The widely employed thiophosphate-based solid electrolytes are not stable toward oxidation and suffer from growing interface resistance and thus rapid fading of capacity in a solid-state battery. In contrast, NASICON-type phosphates such as Li1+ xAl xTi2- x(PO4)3 and Li1+ xAl xGe2- x(PO4)3 are stable at high potentials, but their mechanical rigidity and high grain boundary resistance are thought to impede their application in bulk-type solid-state batteries. In this work, we present a comparative study of a LiNi0.8Co0.1Mn0.1O2 (NCM-811) cathode composite employing either ß-Li3PS4 (LPS) or Li1.5Al0.5Ti1.5(PO4)3 (LATP) as a solid electrolyte. LPS is employed as a separator in both cases to assemble a functional ASSB. To avoid high-temperature processing of LATP, along with subsequent detrimental interfacial reactions with NCM materials, the ASSBs are constructed and operated in a hot-press setup at 150 °C. The cathode interfaces are investigated using in situ electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy, which reveals that the interface resistance is strongly suppressed and the chemical state of the composite is unchanged during cycling when employed with LATP. The cell using LATP is reversibly charged and discharged for multiple cycles and outperforms a comparable cell using a thiophosphate composite electrode. The results indicate that LATP in the cathode composite represents an excellent candidate to overcome interfacial challenges in bulk-type solid-state batteries.

20.
iScience ; 16: 270-282, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31203184

RESUMO

Low lithium-ion migration barriers have recently been associated with low average vibrational frequencies or phonon band centers, further helping identify descriptors for superionic conduction. To further explore this correlation, here we present the computational screening of ∼14,000 Li-containing compounds in the Materials Project database using a descriptor based on lattice dynamics reported recently to identify new promising Li-ion conductors. An efficient computational approach was optimized to compute the average vibrational frequency or phonon band center of ∼1,200 compounds obtained after pre-screening based on structural stability, band gap, and their composition. Combining a low computed Li phonon band center with large computed electrochemical stability window and structural stability, 18 compounds were predicted to be promising Li-ion conductors, one of which, Li3ErCl6, has been synthesized and exhibits a reasonably high room-temperature conductivity of 0.05-0.3 mS/cm, which shows the promise of Li-ion conductor discovery based on lattice dynamics.

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