Engineering Stable Decomposition Products on Cathode Surfaces to Enable High Voltage All-Solid-State Batteries.

Sulfide solid electrolytes such as LiPSCl hold high promise for solid-state batteries due to their high ionic conductivity; however, their oxidation potential of ~2.5 V is not compatible with high voltage Ni-rich cathodes such as LiNiCoMnO (x≥0.8).

Evaluation of Oxide|Sulfide Heteroionic Interface Stability for Developing Solid-State Batteries with a Lithium-Metal Electrode: The Case of LLZO|LiPSCl and LLZO|LiPS.

Developing solid-state batteries (SSB) with a lithium metal electrode (LME) using only one type of solid electrolyte (SE) is a significant challenge since no SE fits all the requirements imposed by both electrodes. A possible solution is using multilayer SSBs with an LME where the drawbacks of each SE are overcome by using layers of different SEs. However, research on inorganic SE|SE heteroionic interfaces is still quite preliminary, especially regarding oxide|sulfide heteroionic interfaces.

Imaging the microstructure of lithium and sodium metal in anode-free solid-state batteries using electron backscatter diffraction.

'Anode-free' or, more fittingly, metal reservoir-free cells could drastically improve current solid-state battery technology by achieving higher energy density, improving safety and simplifying manufacturing. Various strategies have been reported so far to control the morphology of electrodeposited alkali metal films to be homogeneous and dense, but until now, the microstructure of electrodeposited alkali metal is unknown, and a suitable characterization route is yet to be identified. Here we establish a reproducible protocol for characterizing the size and orientation of metal grains in differently processed lithium and sodium samples by a combination of focused ion beam and electron backscatter diffraction.

Critical Role of Framework Flexibility and Disorder in Driving High Ionic Conductivity in LiNbOCl.

Understanding Li-ion transport is key for the rational design of superionic solid electrolytes with exceptional ionic conductivities. LiNbOCl is reported to be one of the most highly conducting materials in the recently realized new class of soft oxyhalide solid electrolytes, exhibiting an ionic conductivity of ∼11 mS·cm. Here, we apply X-ray/neutron diffraction and pair distribution function analysis─coupled with density functional theory/ab initio molecular dynamics (AIMD)─to determine a structural model that provides a rationale for the high conductivity that we observe experimentally in this nanocrystalline solid.

Surface Chemistry of LLZO Garnet Electrolytes with Sulfur in Electron Pair Donor Solvents.

Conventional Li-S batteries rely on liquid electrolytes based on LiNO/DOL/DME mixtures that produce a quasistable interface with the lithium anode. Electron pair donor (EPD) solvents, also known as high donor number solvents, provide much higher polysulfide solubility and close-to-ideal sulfur utilization, making them solvents of choice for lean electrolyte Li-S cells. However, their instability to reduction requires incorporation of an ion-conductive membrane that is stable with Li-such as garnet LLZO and also stable with sulfur/polysulfides.

Enabling selective zinc-ion intercalation by a eutectic electrolyte for practical anodeless zinc batteries.

Two major challenges hinder the advance of aqueous zinc metal batteries for sustainable stationary storage: (1) achieving predominant Zn-ion (de)intercalation at the oxide cathode by suppressing adventitious proton co-intercalation and dissolution, and (2) simultaneously overcoming Zn dendrite growth at the anode that triggers parasitic electrolyte reactions. Here, we reveal the competition between Zn vs proton intercalation chemistry of a typical oxide cathode using ex-situ/operando techniques, and alleviate side reactions by developing a cost-effective and non-flammable hybrid eutectic electrolyte. A fully hydrated Zn solvation structure facilitates fast charge transfer at the solid/electrolyte interface, enabling dendrite-free Zn plating/stripping with a remarkably high average coulombic efficiency of 99.

A New Sodium Thioborate Fast Ion Conductor: Na B S.

We report a new sodium fast-ion conductor, Na B S , that exhibits a high Na ion total conductivity of 0.80 mS cm (sintered pellet; cold-pressed pellet=0.21 mS cm ).

Structure of the Solid-State Electrolyte LiPAlS: Lithium-Ion Transport Properties in Crystalline vs Glassy Phases.

The search for new solid electrolyte materials and an understanding of fast-ion conductivity are crucial for the development of safe and high-power all-solid-state battery technology. Herein, we present the synthesis, structure, and properties of a crystalline lithium-ion conductor, LiAlPS (i.e.

Impact of the Chlorination of Lithium Argyrodites on the Electrolyte/Cathode Interface in Solid-State Batteries.

Lithium argyrodite-type electrolytes are regarded as promising electrolytes due to their high ionic conductivity and good processability. Chemical modifications to increase ionic conductivity have already been demonstrated, but the influence of these modifications on interfacial stability remains so far unknown. In this work, we study Li PS Cl and Li PS Cl to investigate the influence of halogenation on the electrochemical decomposition of the solid electrolyte and the chemical degradation mechanism at the cathode interface in depth.

Fast-charging aluminium-chalcogen batteries resistant to dendritic shorting.

Although batteries fitted with a metal negative electrode are attractive for their higher energy density and lower complexity, the latter making them more easily recyclable, the threat of cell shorting by dendrites has stalled deployment of the technology. Here we disclose a bidirectional, rapidly charging aluminium-chalcogen battery operating with a molten-salt electrolyte composed of NaCl-KCl-AlCl. Formulated with high levels of AlCl, these chloroaluminate melts contain catenated AlCl species, for example, AlCl, AlCl and AlCl, which with their Al-Cl-Al linkages confer facile Al desolvation kinetics resulting in high faradaic exchange currents, to form the foundation for high-rate charging of the battery.

Nanotechnology for a Sustainable Future: Addressing Global Challenges with the International Network4Sustainable Nanotechnology.

Nanotechnology has important roles to play in international efforts in sustainability. We discuss how current and future capabilities in nanotechnology align with and support the United Nations' Sustainable Development Goals. We argue that, as a field, we can accelerate the progress toward these goals both directly through technological solutions and through our special interdisciplinary skills in communication and tackling difficult challenges.

Innovative Approaches to Li-Argyrodite Solid Electrolytes for All-Solid-State Lithium Batteries.

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.

Fast Ion-Conducting Thioboracite with a Perovskite Topology and Argyrodite-like Lithium Substructure.

We report a new fast ion-conducting lithium thioborate halide, LiBSI, that crystallizes in either a cubic or tetragonal thioboracite structure, which is unprecedented in boron-sulfur chemistry. The cubic phase exhibits a perovskite topology and an argyrodite-like lithium substructure that leads to superionic conduction with a theoretical Li-ion conductivity of 5.2 mS cm calculated from ab initio molecular dynamics (AIMD).

Coulombically-stabilized oxygen hole polarons enable fully reversible oxygen redox.

Stabilizing high-valent redox couples and exotic electronic states necessitate an understanding of the stabilization mechanism. In oxides, whether they are being considered for energy storage or computing, highly oxidized oxide-anion species rehybridize to form short covalent bonds and are related to significant local structural distortions. In intercalation oxide electrodes for batteries, while such reorganization partially stabilizes oxygen redox, it also gives rise to substantial hysteresis.

The Role of Metal Substitution in Tuning Anion Redox in Sodium Metal Layered Oxides Revealed by X-Ray Spectroscopy and Theory.

We investigate high-valent oxygen redox in the positive Na-ion electrode P2-Na [Fe Mn ]O (NMF) where Fe is partially substituted with Cu (P2-Na [Mn Fe Cu ]O , NMFC) or Ni (P2-Na [Mn Fe Ni ]O , NMFN). From combined analysis of resonant inelastic X-ray scattering and X-ray near-edge structure with electrochemical voltage hysteresis and X-ray pair distribution function profiles, we correlate structural disorder with high-valent oxygen redox and its improvement by Ni or Cu substitution. Density of states calculations elaborate considerable anionic redox in NMF and NMFC without the widely accepted requirement of an A-O-A' local configuration in the pristine materials (where A=Na and A'=Li, Mg, vacancy, etc.

Fast Li-Ion Conductivity in Superadamantanoid Lithium Thioborate Halides.

Lithium thioborates are promising fast Li-ion conducting materials, with similar properties to their lithium thiophosphate counterparts that have enabled the development of solid-state Li-ion batteries. By comparison, thioborates have scarcely been developed, however, offering new space for materials discovery. Here we report a new class of lithium thioborate halides that adopt a so-called supertetrahedral adamantanoid structure that houses mobile lithium ions and halide anions within interconnected 3D structural channels.

Energy storage emerging: A perspective from the Joint Center for Energy Storage Research.

Energy storage is an integral part of modern society. A contemporary example is the lithium (Li)-ion battery, which enabled the launch of the personal electronics revolution in 1991 and the first commercial electric vehicles in 2010. Most recently, Li-ion batteries have expanded into the electricity grid to firm variable renewable generation, increasing the efficiency and effectiveness of transmission and distribution.

Lithium-Oxygen Batteries and Related Systems: Potential, Status, and Future.

The goal of limiting global warming to 1.5 °C requires a drastic reduction in CO emissions across many sectors of the world economy. Batteries are vital to this endeavor, whether used in electric vehicles, to store renewable electricity, or in aviation.

Stable High-Temperature Cycling of Na Metal Batteries on NaV(PO) and NaFePO Cathodes in NaFSI-Rich Organic Ionic Plastic Crystal Electrolytes.

Sodium batteries have emerged as a promising alternative for large-scale energy storage applications due to the low cost and high abundance of sodium. Sodium batteries require safe, high-voltage, and cost-effective electrolytes and cathode materials for their practical applications to be realized. In the present study, Na metal cells with a mixed-phase electrolyte comprising a high concentration of Na salt in an organic ionic plastic crystal (OIPC), namely, triisobutylmethylphosphonium bis(fluorosulfonyl)imide, are investigated-coupled with either a sodium vanadium phosphate-carbon composite (NVP/C) or a sodium iron pyrophosphate (NFpP) cathode.

Coupled Cation-Anion Dynamics Enhances Cation Mobility in Room-Temperature Superionic Solid-State Electrolytes.

Single-ion conducting solid electrolytes are gaining tremendous attention as essential materials for solid-state batteries, but a comprehensive understanding of the factors that dictate high ion mobility remains elusive. Here, for the first time, we use a combination of the Maximum Entropy Method analysis of room-temperature neutron powder diffraction data, ab initio molecular dynamics, and joint-time correlation analysis to demonstrate that the dynamic response of the anion framework plays a significant role in the new class of fast ion conductors, NaSnPnX (Pn = P, Sb; X = S, Se). Facile [PX] anion rotation exists in superionic NaSnPS and NaSnPSe, but greatly hindered [SbS] rotational dynamics are observed in their less conductive analogue, NaSnSbS.

New Family of Argyrodite Thioantimonate Lithium Superionic Conductors.

We report on a new family of argyrodite lithium superionic conductors, as solid solutions LiMSbSI (M = Si, Ge, Sn), that exhibit superionic conductivity. These represent the first antimony argyrodites to date. Exploration of the series using a combination of single crystal X-ray and synchrotron/neutron powder diffraction, combined with impedance spectroscopy, reveals that an optimal degree of substitution (), and substituent induces slight S/I anion site disorder-but more importantly drives Li cation site disorder.

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

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 PS Cl family, Li PS Cl , and combine electrochemical impedance spectroscopy, neutron diffraction, and Li NMR MAS and PFG spectroscopy to show that increasing the Cl /S ratio has a systematic, and remarkable impact on Li-ion diffusivity in the lattice. The phase at the limit of the solid solution regime, Li PS Cl , exhibits a cold-pressed conductivity of 9.

Elastic and Li-ion-percolating hybrid membrane stabilizes Li metal plating.

Lithium metal batteries are capable of revolutionizing the battery marketplace for electrical vehicles, owing to the high capacity and low voltage offered by Li metal. Current exploitation of Li metal electrodes, however, is plagued by their exhaustive parasitic reactions with liquid electrolytes and dendritic growth, which pose concerns to both cell performance and safety. We demonstrate that a hybrid membrane, both elastic and Li-ion percolating, can stabilize Li plating/stripping with high Coulombic efficiency.

Stabilizing Lithium Plating by a Biphasic Surface Layer Formed In Situ.

The dendritic growth of Li metal leads to electrode degradation and safety concerns, impeding its application in building high energy density batteries. Forming a protective layer on the Li surface that is electron-insulating, ion-conducting, and maintains an intimate interface is critical. We herein demonstrate that Li plating is stabilized by a biphasic surface layer composed of a lithium-indium alloy and a lithium halide, formed in situ by the reaction of an electrolyte additive with Li metal.