Enabling all-solid-state Li-ion batteries requires solid electrolytes with high Li ionic conductivity and good electrochemical stability.F ollowing recent experimental reports of Li 3 YCl 6 and Li 3 YBr 6 as promising new solid electrolytes,weused first principles computation to investigate the Li-ion diffusion, electrochemical stability,a nd interface stability of chloride and bromide materials and elucidated the origin of their high ionic conductivities and good electrochemical stabilities.Chloride and bromide chemistries intrinsically exhibit lowmigration energy barriers,wide electrochemical windows,a nd are not constrained to previous design principles for sulfide and oxide Li-ion conductors,allowing for muchg reater freedom in structure,c hemistry,c omposition, and Li sublattice for developing fast Li-ion conductors.O ur study highlights chloride and bromide chemistries as apromising new researchdirection for solid electrolytes with high ionic conductivity and good stability.All-solid-state lithium-ion batteries (ASBs) with inorganic lithium solid electrolytes (SEs) are regarded as promising next-generation energy storage devices.ASBs solve the safety issue caused by the flammability of organic liquid electrolyte and potentially provide higher energy density with Li metal anode and high-voltage cathode materials. [1] However,i th as been ag reat challenge to develop solid-state Li-ion conductors with high Li + conductivity at room temperature comparable to that of liquid electrolytes and with good electrochemical stability for Li-ion batteries with avoltage of > 4V .C urrent research efforts on solid-state Li-ion conductors focus mostly on oxides and sulfides. [1a,b,2] Unfortunately, oxide and sulfide chemistries have an undesirable trade-off between ionic conductivity and stability.S ulfide-based solidstate Li-ion conductors such as Li 10 GeP 2 S 12 (LGPS) andSupportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.Figure 3. Calculated thermodynamics intrinsic electrochemical windows of Li-M-X ternary fluorides, chlorides, bromides, iodides, oxides, and sulfides. Mi sametal cation at its highest commonv alence state.

Ceramics are an important class of materials with widespread applications because of their high thermal, mechanical, and chemical stability. Computational predictions based on first principles methods can be a valuable tool in accelerating materials discovery to develop improved ceramics. It is essential to experimentally confirm the material properties of such predictions. However, materials screening rates are limited by the long processing times and the poor compositional control from volatile element loss in conventional ceramic sintering techniques. To overcome these limitations, we developed an ultrafast high-temperature sintering (UHS) process for the fabrication of ceramic materials by radiative heating under an inert atmosphere. We provide several examples of the UHS process to demonstrate its potential utility and applications, including advancements in solid-state electrolytes, multicomponent structures, and high-throughput materials screening.

Since the first demonstration of prototype Li batteries (TiS 2 /Li) in 1976, [1] the develo pment of LIBs to date has been strongly affected by safety issues. One of the major technical breakthroughs for the commer cialization of LIBs was the replacement of Li metal with carbonaceous materials as the anode. [2][3][4] It is well known that the use of Li metal was challenged by serious safety concerns associated with internal short circuit by the dendritic growth of Li metal. [5][6][7] The everrising requirements for higher energy density of LIBs have raised more serious safety concerns. Raising the upper cutoff voltages leads to poorer sta bility at electrode-electrolyte interfaces. [8,9] Ultrathinning the polymeric separators to less than 10 µm, despite the reinforce ments using ceramic materials, [10][11][12] result in more vulnerability toward internal short circuits. These may also be related to degassing, fire, and explosion accidents of LIBs in recent years. Further more, largescale applications of LIBs, such as batterydriven electric vehicles and gridscale energy storages, face unprecedented challenges in terms of safety requirements. [13][14][15] In this regard, solidification of conventional flammable organic liquid electrolytes with inorganic materials, such as superionic conductor solid electrolytes (SEs), is an ideal solution. [16][17][18][19][20][21][22][23][24][25] Another strong motivation in the development of SEs is to unleash the harness of limited energy density for con ventional LIBs by using SEs to stabilize and enable alternative highcapacity electrode materials, such as Li metal anode and sulfur cathode. [15,23] Additionally, the design of allsolidstate Li or Liion batteries (ALSBs) by stacking bipolar electrodes allows the minimization of inactive encasing materials, thereby increasing celllevel energy density. [22,26] The first superionic conductors PbF 2 and Ag 2 S were discov ered by Michael Faraday in 1838. [27] Since then, several notable progresses in the field of solidstate superionic conductors and their newly enabled electrochemical devices had occurred; [27] the development of oxygenion conductors (Ydoped ZrO 2 ) applied to solid oxide fuel cells, the discoveries of Ag + superionic conduc tors (e.g., RbAg 4 I 5 ), and the development of Naion conducting sodium beta alumina (β″Al 2 O 3 ). Currently, it is a promi sing opportunity for Liion SEs to revolutionize LIB technologies Owing to the ever-increasing safety concerns about conventional lithium-ion batteries, whose applications have expanded to include electric vehicles and grid-scale energy storage, batteries with solidified electrolytes that utilize nonflammable inorganic materials are attracting considerable attention. In particular, owing to their superionic conductivities (as high as ≈10 −2 S cm −1 ) and deformability, sulfide materials as the solid electrolytes (SEs) are considered the enabling material for high-energy bulk-type all-solid-state batteries. Herein the authors provide a brief review on recent progress in sulf...

The all-solid-state lithium-ion battery is a promising next-generation battery technology. However, the realization of all-solid-state batteries is impeded by limited understanding of solid electrolyte materials and solid electrolyte-electrode interfaces. In this review, we present an overview of recently developed computation techniques and their applications in understanding and advancing materials and interfaces in all-solid-state batteries. We review the role of ab initio molecular dynamics simulations in studying fast ion conductors and discuss the capabilities of thermodynamic calculations powered by materials databases for identifying the chemical and electrochemical stability of solid electrolyte materials and solid electrolyte-electrode interfaces. We highlight the computational studies in the design and discovery of new solid electrolyte materials and outline design guidelines for solid electrolytes and their interfaces. We conclude with discussion of future directions in computation techniques, materials development, and interface engineering for all-solid-state lithium-ion batteries.

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Although machine learning has gained great interest in the discovery of functional materials, the advancement of reliable models is impeded by the scarcity of available materials property data. Here we propose and demonstrate a distinctive approach for materials discovery using unsupervised learning, which does not require labeled data and thus alleviates the data scarcity challenge. Using solid-state Li-ion conductors as a model problem, unsupervised materials discovery utilizes a limited quantity of conductivity data to prioritize a candidate list from a wide range of Li-containing materials for further accurate screening. Our unsupervised learning scheme discovers 16 new fast Li-conductors with conductivities of 10−4–10−1 S cm−1 predicted in ab initio molecular dynamics simulations. These compounds have structures and chemistries distinct to known systems, demonstrating the capability of unsupervised learning for discovering materials over a wide materials space with limited property data.

Sodium‐ion batteries have attracted extensive interest as a promising solution for large‐scale electrochemical energy storage, owing to their low cost, materials abundance, good reversibility, and decent energy density. For sodium‐ion batteries to achieve comparable performance to current lithium‐ion batteries, significant improvements are still required in cathode, anode, and electrolyte materials. Understanding the functioning and degradation mechanisms of the materials is essential. Computational techniques have been widely applied in tandem with experimental investigations to provide crucial fundamental insights into electrode materials and to facilitate the development of materials for sodium‐ion batteries. Herein, the authors review computational studies on electrode materials in sodium‐ion batteries. The authors summarize the current state‐of‐the‐art computational techniques and their applications in investigating the structure, ordering, diffusion, and phase transformation in cathode and anode materials for sodium‐ion batteries. The unique capability and the obtained knowledge of computational studies as well as the perspectives for sodium‐ion battery materials are discussed in this review.

replacement of liquid electrolyte and has the potential to achieve improved safety, higher energy density, and longer cycle life than current commercial lithiumion batteries with liquid electrolytes. [17] Despite significant research efforts, only a few Li SIC materials exhibit an ionic conductivity of >10 −3 S cm −1 at room temperature, and some Li SICs suffer from limited stability, poor interfacial compatibility, or high cost in processing and manufacturing. [6,7,18] A strong need exists for fundamental understanding of these SIC materials in order to design and discover new Li SIC materials.A Li-ion conductor material is comprised of a mobile Li-ion sublattice hosted in a crystal structural framework of immobile polyanion groups. The empty space in between these polyanion groups hosts Li ions as Li sites and forms interconnected channels. Li ions migrate among the sites through these channels, contributing to overall ionic transport. Well-known crystal structural frameworks of SICs include NASICON structure of LiM 2 (PO 4 ) 3 (M = Ge, Ti, Sn, Hf, Zr) compositions, [19] garnet structure of Li x La 3 M 2 O 12 (5 ≤ x ≤ 7, M = Nb, Ta, Sb, Zr, Sn) compositions, [20] and LGPS-type structure of Li 10+x M 1+x P 2−x S 12 (0 ≤ x ≤ 1, M = Si, Ge, Sn) compositions. [21] Recent studies have demonstrated that the crystal structural framework determines Li sites, migration pathways, and the energy landscape, and particular crystal structural frameworks are optimal for low energy barrier Li ion migration. [10,22,23] For example, the crystal structural framework with a body-centered cubic (bcc) anion sublattice, such as found in LGPS and Li 7 P 3 S 11 , has been shown to have an energy landscape with the lowest barrier compared to other anion sublattices, such as in facecentered cubic and hexagonal close packed sublattices. [10] However, some SICs with crystal structural frameworks of non-bcc anion sublattices, such as lithium garnet (e.g., LLZO) and lithium NASICON (e.g., LATP), also exhibit high Li + conductivities as high as ≈10 −3 S cm −1 at RT. It remains an open question as to what features of these crystal structure frameworks enable super-ionic conduction.Due to their unique crystal structural frameworks, SIC materials have highly mobile Li-ion sublattices, which are drastically different from those in typical solids (Figure 1). The disordered Li sublattice of SICs facilitates the transport of a large number of Li ions and yields high ionic conductivity. In the disordered Li sublattice, the Li-ion diffusion mechanism is also distinctive As technologically important materials for solid-state batteries, Li superionic conductors are a class of materials exhibiting exceptionally high ionic conductivity at room temperature. These materials have unique crystal structural frameworks hosting a highly conductive Li sublattice. However, it is not understood why certain crystal structures of the super-ionic conductors lead to high conductivity in the Li sublattice. In this study, using topological analysis and ab initio molecula...