Chemical Prelithiated 3D Lithiophilic/-Phobic Interlayer Enables Long-Term Li Plating/Stripping.

The up-to-date lifespan of zero-excess lithium (Li) metal batteries is limited to a few dozen cycles due to irreversible Li-ion loss caused by interfacial reactions during cycling. Herein, a chemical prelithiated composite interlayer, made of lithiophilic silver (Ag) and lithiophobic copper (Cu) in a 3D porous carbon fiber matrix, is applied on a planar Cu current collector to regulate Li plating and stripping and prevent undesired reactions. The Li-rich surface coating of lithium oxide (LiO), lithium carboxylate (RCOLi), lithium carbonates (ROCOLi), and lithium hydride (LiH) is formed by soaking and directly heating the interlayer in -butyllithium hexane solution.

Weak-Interaction Environment in a Composite Electrolyte Enabling Ultralong-Cycling High-Voltage Solid-State Lithium Batteries.

Poly(vinylidene fluoride) (PVDF)-based solid electrolytes with a Li salt-polymer-little residual solvent configuration are promising candidates for solid-state batteries. Herein, we clarify the microstructure of PVDF-based composite electrolyte at the atomic level and demonstrate that the Li-interaction environment determines both interfacial stability and ion-transport capability. The polymer works as a "solid diluent" and the filler realizes a uniform solvent distribution.

A Robust Anti-Thermal-Quenching Phosphor Based on Zero-Dimensional Metal Halide RbInCl:Sb.

High-power phosphor-converted white light-emitting diodes (hp-WLEDs) have been widely involved in modern society as outdoor lighting sources. In these devices, due to the Joule effect, the high applied currents cause high operation temperatures (>500 K). Under these conditions, most phosphors lose their emission, an effect known as thermal quenching (TQ).

Disentangling the Li-Ion transport and Boundary Phase Transition Processes in Li GeP S Electrolyte by In-Operando High-Pressure and High-Resolution NMR Spectroscopy.

Li-ion transport and phase transition of solid electrolytes are critical and fundamental issues governing the rate and cycling performances of solid-state batteries. In this work, in-operando high-pressure nuclear magnetic resonance (NMR) spectroscopy for the solid-state battery is developed and applied, in combination with Li-tracer NMR and high-resolution NMR spectroscopy, to investigate the Li GeP S electrolyte under true-to-life operation conditions. The results reveal that the Li GeP S phase may become more disordered and a large amount of conductive metastable β-Li PS as the glassy matrix in the electrolyte transforms into less conductive phases, mainly γ-Li PS , when high current densities (e.

A dielectric electrolyte composite with high lithium-ion conductivity for high-voltage solid-state lithium metal batteries.

The ionic conductivity of composite solid-state electrolytes does not meet the application requirements of solid-state lithium (Li) metal batteries owing to the harsh space charge layer of different phases and low concentration of movable Li. Herein, we propose a robust strategy for creating high-throughput Li transport pathways by coupling the ceramic dielectric and electrolyte to overcome the low ionic conductivity challenge of composite solid-state electrolytes. A highly conductive and dielectric composite solid-state electrolyte is constructed by compositing the poly(vinylidene difluoride) matrix and the BaTiO-LiLaTiO nanowires with a side-by-side heterojunction structure (PVBL).

Lithium-ion spontaneous exchange and synergistic transport in ceramic-liquid hybrid electrolytes for highly efficient lithium-ion transfer.

Ceramic electrolytes are important in ceramic-liquid hybrid electrolytes (CLHEs), which can effectively solve the interfacial issues between the electrolyte and electrodes in solid-state batteries and provide a highly efficient Li-ion transfer for solid-liquid Li metal batteries. Understanding the ionic transport mechanisms in CLHEs and the corresponding role of ceramic electrolytes is crucial for a rational design strategy. Herein, the Li-ion transfer in the ceramic electrolytes of CLHEs was confirmed by tracking the Li and Li substitution behavior through solid-state nuclear magnetic resonance spectroscopy.

Quasi-Solid-State Ion-Conducting Arrays Composite Electrolytes with Fast Ion Transport Vertical-Aligned Interfaces for All-Weather Practical Lithium-Metal Batteries.

The rapid improvement in the gel polymer electrolytes (GPEs) with high ionic conductivity brought it closer to practical applications in solid-state Li-metal batteries. The combination of solvent and polymer enables quasi-liquid fast ion transport in the GPEs. However, different ion transport capacity between solvent and polymer will cause local nonuniform Li distribution, leading to severe dendrite growth.

Structure and Performance of NaMnAlFeO (0.7 ≤ ≤ 1.0) Composite Materials for Sodium-Ion Batteries.

P2 and O3 structures are two important sodium manganese oxide phases for sodium-ion batteries; however, encounter Na-deficient and poor rate performance, respectively. Herein, a systematic study of NaMnAlFeO (0.7 ≤ ≤ 1.

Electrochemistry of P-C Bonds in Phosphorus-Carbon Based Anode Materials.

Phosphorus-carbon anode materials for alkali-metal ion storage in rechargeable batteries can simultaneously achieve high-energy density and fast charging. The P-C-bonded structure in the phosphorus-carbon materials has been observed and acknowledged to be a critical structural feature that renders improved cycling stability and rate performance. However, the underlying mechanisms, especially the role played by P-C bonds, remain elusive.

Interfacial Barrier of Ion Transport in Poly(ethylene oxide)-LiLaZrO Composite Electrolytes Illustrated by Li-Tracer Nuclear Magnetic Resonance Spectroscopy.

Fundamental understanding of the lithium-ion transport mechanism in polymer-inorganic composite electrolyte is crucially important for the rational design of composite electrolytes for solid-state batteries. In this work, the Li ion transport pathway in a model composite electrolyte of PEO containing sparsely dispersed LLZO (PEO-LLZO) was studied by an advanced characterization technique, i.e.

Quantitatively analyzing the failure processes of rechargeable Li metal batteries.

Practical use of lithium (Li) metal for high–energy density lithium metal batteries has been prevented by the continuous formation of Li dendrites, electrochemically isolated Li metal, and the irreversible formation of solid electrolyte interphases (SEIs). Differentiating and quantifying these inactive Li species are key to understand the failure mode. Here, using operando nuclear magnetic resonance (NMR) spectroscopy together with ex situ titration gas chromatography (TGC) and mass spectrometry titration (MST) techniques, we established a solid foundation for quantifying the evolution of dead Li metal and SEI separately.

Electron and Ion Co-Conductive Catalyst Achieving Instant Transformation of Lithium Polysulfide towards Li S.

Most of the catalysts in lithium sulfur (Li-S) batteries present low electronic conductivity and the lithium polysulfides (LiPSs) must diffuse onto the surface of the carbon materials to achieve their conversion reaction. It is a significant challenge to achieve the instantaneous transformation of LiPSs to Li S in Li-S batteries to suppress the shuttle effect of LiPSs. Herein, a unique electron and ion co-conductive catalyst of carbon-coated Li Al Ti (PO ) (C@LATP) is developed, which not only possesses strong adsorption to LiPSs, but, more importantly, also promotes the instantaneous conversion reaction of LiPSs to Li S.

Stable Interface Chemistry and Multiple Ion Transport of Composite Electrolyte Contribute to Ultra-long Cycling Solid-State LiNi Co Mn O /Lithium Metal Batteries.

Severe interfacial side reactions of polymer electrolyte with LiNi Co Mn O (NCM811) cathode and Li metal anode restrict the cycling performance of solid-state NCM811/Li batteries. Herein, we propose a chemically stable ceramic-polymer-anchored solvent composite electrolyte with high ionic conductivity of 6.0×10  S cm , which enables the solid-state NCM811/Li batteries to cycle 1500 times.

Adjusting Rotational Behavior of Molecular Rotors by a Rational Tuning of Molecular Structure.

Many crystalline molecular rotors have been developed in the past decades. However, manipulating the rotational gesture that intrinsically controls the physical performance of materials remains a challenge. Herein, we report a series of crystalline rotors whose rotational gestures can be modulated by modifying the structures of molecular stators.

Solid-State NMR and MRI Spectroscopy for Li/Na Batteries: Materials, Interface, and In Situ Characterization.

Enhancing the electrochemical performance of batteries, including the lifespan, energy, and power densities, is an everlasting quest for the rechargeable battery community. However, the dynamic and coupled (electro)chemical processes that occur in the electrode materials as well as at the electrode/electrolyte interfaces complicate the investigation of their working and decay mechanisms. Herein, the recent developments and applications of solid-state nuclear magnetic resonance (ssNMR) and magnetic resonance imaging (MRI) techniques in Li/Na batteries are reviewed.

Insight into Ion Diffusion Dynamics/Mechanisms and Electronic Structure of Highly Conductive Sodium-Rich NaLaZrSiPO (0 ≤ ≤ 0.5) Solid-State Electrolytes.

Solid-state electrolytes (SSEs) have attracted considerable attention as an alternative for liquid electrolytes to improve safety and durability. Sodium Super Ionic CONductor (NASICON)-type SSEs, typically NaZrSiPO, have shown great promise because of their high ionic conductivity and low thermal expansivity. Doping La into the NASICON structure can further elevate the ionic conductivity by an order of magnitude to several mS/cm.

Mn-Substituted Li-Rich LiMnMnTiO Materials with High Energy Density.

In this work, Li-rich LiMnMnTiO (LMMTO, 0 ≤ ≤ 0.4) oxides have been studied for the first time. X-ray diffraction (XRD) patterns show a cation-disordered rocksalt structure when ranges from 0 to 0.

Visualizing the growth process of sodium microstructures in sodium batteries by in-situ Na MRI and NMR spectroscopy.

The growth of sodium dendrites and the associated solid electrolyte interface (SEI) layer is a critical and fundamental issue influencing the safety and cycling lifespan of sodium batteries. In this work, we use in-situ Na magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) techniques, along with an innovative analytical approach, to provide space-resolved and quantitative insights into the formation and evolution of sodium metal microstructures (SMSs; that is, dendritic and mossy Na metal) during the deposition and stripping processes. Our results reveal that the growing SMSs give rise to a linear increase in the overpotential until a transition voltage of 0.

Synthesis and characterization of a nanocluster-based silver(i) tert-butylethynide compound with a large second-harmonic generation response.

A new nanocluster-based silver(i) tert-butylethynide compound, namely, (tBuC[triple bond, length as m-dash]CAg)2(Ag4SiW12O40)(DMSO)6 (HT-1), has been synthesized and structurally characterized by X-ray crystallography. The two kinds of nanocluster synthons (a silver aggregate named [(tBuC[triple bond, length as m-dash]C)2Ag6(DMSO)6] and a SiW12 polyoxoanion) are assembled into a three-dimensional coordination network, which has a non-centrosymmetric crystal lattice. Powder second-harmonic generation (SHG) measurements reveal that HT-1 belongs to the phase-matchable class with a moderately strong SHG response of about 3 times that of the KH2PO4 (KDP) sample.

Polymeric Sulfur as a Li Ion Conductor.

The typical polymer electrolyte matrix has been limited to the chains consisting of -C-C- or -C-O-C- or -Si-O- backbone with different solvating groups for decades. In this work, the polymeric sulfur consisting of -(S-S)- backbone with a high sulfur content (up to 90 wt % S) was reported for the first time. The flexible -(S-S)- chains with high S atom density create an intense "solvating" environment for Li conduction, achieving an excellent Li conductivity of 1.

Elucidating and Mitigating the Degradation of Cationic-Anionic Redox Processes in LiMnTiO Cation-Disordered Cathode Materials.

Cation-disordered rock-salt oxides with the O/O redox reaction, such as LiMnTiO (LMTO), are critical Li-rich cathode materials for designing high-energy-density batteries. Understanding the cationic-anionic redox accompanying the structural evolution process is really imperative to further improve the performance. In this work, the cationic-anionic redox and capacity degradation mechanism of carbon-coated LMTO during (dis)charge processes are elucidated by combining in situ X-ray diffraction, X-ray absorption near-edge spectroscopy, differential electrochemical mass spectrometry, transmission electron microscopy, and electrochemical analyses.

P2-Na Al Mn O : Cost-Effective, Stable and High-Rate Sodium Electrodes by Suppressing Phase Transitions and Enhancing Sodium Cation Mobility.

Sodium layered P2-stacking Na MnO materials have shown great promise for sodium-ion batteries. However, the undesired Jahn-Teller effect of the Mn /Mn redox couple and multiple biphasic structural transitions during charge/discharge of the materials lead to anisotropic structure expansion and rapid capacity decay. Herein, by introducing abundant Al into the transition-metal layers to decrease the number of Mn , we obtain the low cost pure P2-type Na Al Mn O (x=0.

Cross-linked beta alumina nanowires with compact gel polymer electrolyte coating for ultra-stable sodium metal battery.

Sodium metal batteries have potentially high energy densities, but severe sodium-dendrite growth and side reactions prevent their practical applications, especially at high temperatures. Herein, we design an inorganic ionic conductor/gel polymer electrolyte composite, where uniformly cross-linked beta alumina nanowires are compactly coated by a poly(vinylidene fluoride-co-hexafluoropropylene)-based gel polymer electrolyte through their strong molecular interactions. These  beta alumina nanowires combined with the gel polymer layer create dense and homogeneous solid-liquid hybrid sodium-ion transportation channels through and along the nanowires, which promote uniform sodium deposition and formation of a stable and flat solid electrolyte interface on the sodium metal anode.

Polymer Electrolyte Glue: A Universal Interfacial Modification Strategy for All-Solid-State Li Batteries.

In recent years solid Li conductors with competitive ionic conductivity to those of liquid electrolytes have been reported. However, the incorporation of highly conductive solid electrolytes into the lithium-ion batteries is still very challenging mainly due to the high resistance existing at the solid-solid interfaces throughout the battery structure. Here, we demonstrated a universal interfacial modification strategy through coating a curable polymer-based glue electrolyte between the electrolyte and electrodes, aiming to address the poor solid-solid contact and thus decrease high interfacial resistance.