Decoupling the air sensitivity of Na-layered oxides.

Air sensitivity remains a substantial barrier to the commercialization of sodium (Na)-layered oxides (NLOs). This problem has puzzled the community for decades because of the complexity of interactions between air components and their impact on both bulk and surfaces of NLOs. We show here that water vapor plays a pivotal role in initiating destructive acid and oxidative degradations of NLOs only when coupled with carbon dioxide or oxygen, respectively.

Overcoming Kinetic Limitations of Polyanionic Cathode toward High-Performance Na-Ion Batteries.

Polyanionic cathodes have attracted extensive research interest for Na-ion batteries (NIBs) due to their moderate energy density and desirable cycling stability. However, these compounds suffer from visible capacity fading and significant voltage decay upon the rapid sodium storage process, even if modified through nanoengineering or carbon-coating routes, leading to limited applications in NIBs. Herein, the Na(VOPO)F cathode material with dominantly exposed {001} active facets is demonstrated by a topochemical synthesis route.

Ultralight Electrolyte with Protective Encapsulation Solvation Structure Enables Hybrid Sulfur-Based Primary Batteries Exceeding 660 Wh/kg.

An electrochemical couple of lithium and sulfur possesses the highest theoretical energy density (>2600 Wh/kg) at the material level. However, disappointingly, it is out of place in primary batteries due to its low accessible energy density at the cell level (≤500 Wh/kg) and poor storage performance. Herein, a low-density methyl -butyl ether was tailored for an ultralight electrolyte (0.

Dendrite-Free Dual-Phase Li-Ba Alloy Anode Enabled by Ordered Array of Built-in Mixed Conducting Microchannels.

The development and application of lithium (Li) anode is hindered by volumetric variation, dendritic Li growth, and parasitic reactions. Herein, a dual-phase Li-barium (Ba) alloy with self-assembled microchannels array is synthesized through a one-step thermal fusion method to investigate the inhibition effect of lithiophilic composite porous array on Li dendrites. The Li-rich Li-Ba alloy (BaLi24) as composite Li electrode exhibits an ordered porous structure of BaLi intermetallic compound after delithiation, which acts as a built-in 3D current collector during Li plating/striping process.

Polyanionic Cathode Materials for Practical Na-Ion Batteries toward High Energy Density and Long Cycle Life.

Na-ion batteries (NIBs) as a supplement to Li-ion batteries deliver huge application potential in the field of grid-scale energy storage. At present, it is a particularly imperative to advance commercialization of the NIBs after ten years of intensive research. Among the exploited cathodes for NIBs, polyanionic compounds have great commercial prospects due to their favorable ion diffusion channels, high safety, and superior structure stability determined by their unique structure framework; however, there is still a long way to go before large-scale industrialization can be realized.

Investigating the Superior Performance of Hard Carbon Anodes in Sodium-Ion Compared With Lithium- and Potassium-Ion Batteries.

Emerging sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs) show promise in complementing lithium-ion battery (LIB) technology and diversifying the battery market. Hard carbon is a potential anode candidate for LIBs, NIBs, and KIBs due to its high capacity, sustainability, wide availability, and stable physicochemical properties. Herein, a series of hard carbons is synthesized by hydrothermal carbonization and subsequent pyrolysis at different temperatures to finely tune their structural properties.

Tailoring Electronic Structure to Achieve Maximum Utilization of Transition Metal Redox for High-Entropy Na Layered Oxide Cathodes.

Charge compensation from cationic and anionic redox couples accompanying Na (de)intercalation in layered oxide cathodes contributes to high specific capacity. However, the engagement level of different redox couples remains unclear and their relationship with Na content is less studied. Here we discover that it is possible to take full advantage of the high-voltage transition metal (TM) redox reaction through low-valence cation substitution to tailor the electronic structure, which involves an increased ratio of Na content to available charge transfer number of TMs.

Unraveling the Reaction Mystery of Li and Na with Dry Air.

Li and Na metals with high energy density are promising in application in rechargeable batteries but suffer from degradation in the ambient atmosphere. The phenomenon that in terms of kinetics, Li is stable but Na is unstable in dry air has not been fully understood. Here, we use environmental transmission electron microscopy combined with theoretical simulations and reveal that the different stabilities in dry air for Li and Na are reflected by the formation of compact LiO layers on Li metal, while porous and rough NaO/NaO layers on Na metal are a consequence of the different thermodynamic and kinetics in O.

Conversion of Surface Residual Alkali to Solid Electrolyte to Enable Na-Ion Full Cells with Robust Interfaces.

The deposition of volatilized Na on the surface of the cathode during sintering results in the formation of surface residual alkali (NaOH/Na CO NaHCO ) in layered cathode materials, leading to serious interfacial reactions and performance degradation. This phenomenon is particularly evident in O3-NaNi Cu Mn Ti O (NCMT). In this study, a strategy is proposed to transform waste into treasure by converting residual alkali into a solid electrolyte.

Anion-enrichment interface enables high-voltage anode-free lithium metal batteries.

Aggressive chemistry involving Li metal anode (LMA) and high-voltage LiNiMnCoO (NCM811) cathode is deemed as a pragmatic approach to pursue the desperate 400 Wh kg. Yet, their implementation is plagued by low Coulombic efficiency and inferior cycling stability. Herein, we propose an optimally fluorinated linear carboxylic ester (ethyl 3,3,3-trifluoropropanoate, FEP) paired with weakly solvating fluoroethylene carbonate and dissociated lithium salts (LiBF and LiDFOB) to prepare a weakly solvating and dissociated electrolyte.

Surface Engineering Stabilizes Rhombohedral Sodium Manganese Hexacyanoferrates for High-Energy Na-Ion Batteries.

The rhombohedral sodium manganese hexacyanoferrate (MnHCF) only containing cheap Fe and Mn metals was regarded as a scalable, low-cost, and high-energy cathode material for Na-ion batteries. However, the unexpected Jahn-teller effect and significant phase transformation would cause Mn dissolution and anisotropic volume change, thus leading to capacity loss and structural instability. Here we report a simple room-temperature route to construct a magical Co B skin on the surface of MnHCF.

Role of Defects, Pores, and Interfaces in Deciphering the Alkali Metal Storage Mechanism in Hard Carbon.

There are several questions and controversies regarding the Na storage mechanism in hard carbon. This springs from the difficulty of probing the vast diversity of possible configurational environments for Na storage, including surface and defect sites, edges, pores, and intercalation morphologies. In the effort to explain the observed voltage profile, typically existing of a voltage slope section and a low-voltage plateau, several experimental and computational studies have provided a variety of contradicting results.

High-Entropy Microdomain Interlocking Polymer Electrolytes for Advanced All-Solid-State Battery Chemistries.

All-solid-state polymer electrolytes (ASPEs) with excellent processivity are considered one of the most forward-looking materials for large-scale industrialization. However, the contradiction between improving the mechanical strength and accelerating the ionic migration of ASPEs has always been difficult to reconcile. Herein, a rational concept is raised of high-entropy microdomain interlocking ASPEs (HEMI-ASPEs), inspired by entropic elasticity well-known in polymer and biochemical sciences, by introducing newly designed multifunctional ABC miktoarm star terpolymers into polyethylene oxide for the first time.

Sodium Dual-Ion Batteries with Concentrated Electrolytes.

Na-based dual-ion batteries (DIBs) are a class of post-lithium technology with advantages including extremely fast charging, cost-effectiveness, and high natural abundance of raw materials. Operating up to high voltages (≈5.0 V), the decomposition of classic carbonate-based electrolyte formulations and the subsequent fade of capacity continues to be a major drawback in the development of these systems.

Rational design of a topological polymeric solid electrolyte for high-performance all-solid-state alkali metal batteries.

Poly(ethylene oxide)-based solid-state electrolytes are widely considered promising candidates for the next generation of lithium and sodium metal batteries. However, several challenges, including low oxidation resistance and low cation transference number, hinder poly(ethylene oxide)-based electrolytes for broad applications. To circumvent these issues, here, we propose the design, synthesis and application of a fluoropolymer, i.

Using High-Entropy Configuration Strategy to Design Na-Ion Layered Oxide Cathodes with Superior Electrochemical Performance and Thermal Stability.

Na-ion layered oxide cathodes (NaTMO, TM = transition metal ion(s)), as an analogue of lithium layered oxide cathodes (such as LiCoO, LiNiCoMnO), have received growing attention with the development of Na-ion batteries. However, due to the larger Na radius and stronger Na-Na electrostatic repulsion in NaO slabs, some undesired phase transitions are observed in NaTMO. Herein, we report a high-entropy configuration strategy for NaTMO cathode materials, in which multicomponent TMO slabs with enlarged interlayer spacing help strengthen the whole skeleton structure of layered oxides through mitigating Jahn-Teller distortion, Na/vacancy ordering, and lattice parameter changes.

A Better Choice to Achieve High Volumetric Energy Density: Anode-Free Lithium-Metal Batteries.

Volumetric energy density is a critical but easily neglected index of lithium-metal batteries (LMBs). Compared with gravimetric energy density, the volumetric energy density (VED) of LMBs is much more sensitive to the anode/cathode (A/C) ratio due to the low density of lithium (Li) metal and the volume expansion of the Li-metal anode owing to its pulverization during cycles. Anode-free LMBs (AF-LMBs) have high theoretical VED due to the absence of an anode and high retention with relatively low cell expansion.

[Formulation regularity of traditional Chinese medicine in treatment of sinusitis based on data mining].

Based on the Drugdataexpy and the prescription modern application database, this study explored the formulation regularity of ancient and modern prescriptions for the treatment of sinusitis. The Chinese medicinal prescriptions for the treatment of sinusitis with various syndromes were retrieved from the above databases and the corresponding formulation regularity was investigated by frequency analysis, association rule analysis, and factor analysis. Eighty-seven Chinese medicinal prescriptions were included, involving five syndrome types of sinusitis and 160 Chinese medicine, which were mainly effective in releasing exterior, clearing heat, and tonifying deficiency, and acted on the lung meridian due to cold and warm nature and pungent and bitter flavor or on the spleen meridian due to warm nature and pungent flavor.

Regulated Synthesis of α-NaVOPO with an Enhanced Conductive Network as a High-Performance Cathode for Aqueous Na-Ion Batteries.

The low-cost and profusion of sodium reserves make Na-ion batteries (NIBs) a potential candidate to lithium-ion batteries for grid-scale energy storage applications. NaVOPO has been recognized as one of the most promising cathodes for high-energy NIBs, owing to their high theoretical capacity and energy density. However, their further application is hindered by the multiphase transition and conductivity confinement.