Balancing Electronic Spin State via Atomically-Dispersed Heteronuclear Fe-Co Pairs for High-Performance Sodium-Sulfur Batteries.

Room-temperature sodium-sulfur (Na-S) batteries are emerging as a promising next-generation energy storage technology, offering high energy densities at low cost and utilizing abundant elements. However, their practical application is hindered by the shuttle effect of sodium-polysulfides and the sluggish kinetics of sulfur redox reactions. In this study, we demonstrate a heteronuclear diatomic catalyst featuring Fe and Co bimetallic sites embedded in nitrogen-doped hollow carbon nanospheres (Fe-Co/NC) as an effective sulfur host at the cathode of Na-S batteries.

Turning Residual Lithium Compounds into a Fluorinated Interface for a Water-Stable, Industrializable Prelithiated Micron-SiO Anode.

The implementation of carbon-coated microsized SiO (MSiO@C) materials in high energy density lithium-ion batteries (LIBs) is challenged by their low initial Coulombic efficiency (ICE), large volume expansion, and limited cycle life. Even though prelithiation is an effective strategy to enhance ICE, it will make the prelithiated MSiO@C (Li-MSiO@C) extremely sensitive to moisture. For industrial applications, it is important to develop chemically and electrochemically stable Li-MSiO@C with high ICE and good cycling performance.

Insights into the Electrolyte Hydrolysis and Its Impacts on the Interfacial Chemistry of a Li-Intercalated Anode during High-Temperature Calendar Aging.

Calendar aging occurring during high-temperature storage has long plagued practical realization of long-life, high-safety lithium-ion batteries (LIBs). Generally, the aging process is ascribed to the hydrolysis reaction of fluorine-containing electrolyte salt that generates hydrofluoric acid and chemically corrodes the anode surface. Nevertheless, the underlying mechanism about electrolyte degradation, HF generation and surface corrosion remains concealed for various electrolytes.

Localized High-Concentration Electrolyte for All-Carbon Rechargeable Dual-Ion Batteries with Durable Interfacial Chemistry.

Lithium-based rechargeable dual-ion batteries (DIBs) based on graphite anode-cathode combinations have received much attention due to their high resource abundance and low cost. Currently, the practical realization of the batteries is hindered by easy oxidation of the electrolyte at the cathode interface, and solvent co-intercalation at the anode-electrolyte interface. Configuration of a "solvent-in-salt" electrolyte with a high concentration of Li salt is expected to stabilize the electrolyte chemistry versus both electrodes, yet inevitably reduces the mobility of the solvated working ions and increases the cost of the electrolyte.

Sodium layered oxide cathodes: properties, practicality and prospects.

Rechargeable sodium-ion batteries (SIBs) have emerged as an advanced electrochemical energy storage technology with potential to alleviate the dependence on lithium resources. Similar to Li-ion batteries, the cathode materials play a decisive role in the cost and energy output of SIBs. Among various cathode materials, Na layered transition-metal (TM) oxides have become an appealing choice owing to their facile synthesis, high Na storage capacity/voltage that are suitable for use in high-energy SIBs, and high adaptivity to the large-scale manufacture of Li layered oxide analogues.

Quantification of Charge Transport and Mass Deprivation in Solid Electrolyte Interphase for Kinetically-Stable Low-Temperature Lithium-Ion Batteries.

Graphite (Gr)-based lithium-ion batteries with admirable electrochemical performance below -20 °C are desired but are hindered by sluggish interfacial charge transport and desolvation process. Li salt dissociation via Li-solvent interaction enables mobile Li liberation and contributes to bulk ion transport, while is contradictory to fast interfacial desolvation. Designing kinetically-stable solid electrolyte interphase (SEI) without compromising strong Li-solvent interaction is expected to compatibly improve interfacial charge transport and desolvation kinetics.

In Situ Analysis of Interfacial Morphological and Chemical Evolution in All-Solid-State Lithium-Metal Batteries.

In situ analysis of Li plating/stripping processes and evolution of solid electrolyte interphase (SEI) are critical for optimizing all-solid-state Li metal batteries (ASSLMB). However, the buried solid-solid interfaces present a challenge for detection which preclude the employment of multiple analysis techniques. Herein, by employing complementary in situ characterizations, morphological/chemical evolution, Li plating/stripping dynamics and SEI dynamics were directly detected.

Reviving Fatigue Surface for Solid-State Upcycling of Highly Degraded Polycrystalline LiNiCoMnO Cathodes.

The ongoing tide of spent lithium-ion batteries (LIBs) urgently calls for high-value output in efficient recycling. Recently, direct regeneration has emerged as a novel recycling strategy but fails to repair the irreversible morphology and structure damage of the highly degraded polycrystalline layered oxide materials. Here, this work carries out a solid-state upcycling study for the severely cracked LiNiCoMnO cathodes.

Boosting Sodium Compensation Efficiency via a CNT/MnO Catalyst toward High-Performance Na-Ion Batteries.

The formation of a solid electrolyte interphase on carbon anodes causes irreversible loss of Na ions, significantly compromising the energy density of Na-ion full cells. Sodium compensation additives can effectively address the irreversible sodium loss but suffer from high decomposition voltage induced by low electrochemical activity. Herein, we propose a universal electrocatalytic sodium compensation strategy by introducing a carbon nanotube (CNT)/MnO catalyst to realize full utilization of sodium compensation additives at a much-reduced decomposition voltage.

An ultralight, pulverization-free integrated anode toward lithium-less lithium metal batteries.

The high-capacity advantage of lithium metal anode was compromised by common use of copper as the collector. Furthermore, lithium pulverization associated with "dead" Li accumulation and electrode cracking deteriorates the long-term cyclability of lithium metal batteries, especially under realistic test conditions. Here, we report an ultralight, integrated anode of polyimide-Ag/Li with dual anti-pulverization functionality.

The electrochemistry of stable sulfur isotopes versus lithium.

Sulfur in nature consists of two abundant stable isotopes, with two more neutrons in the heavy one (S) than in the light one (S). The two isotopes show similar physicochemical properties and are usually considered an integral system for chemical research in various fields. In this work, a model study based on a Li-S battery was performed to reveal the variation between the electrochemical properties of the two S isotopes.

Reduced Volume Expansion of Micron-Sized SiO via Closed-Nanopore Structure Constructed by Mg-Induced Elemental Segregation.

The inherently huge volume expansion during Li uptake has hindered the use of Si-based anodes in high-energy lithium-ion batteries. While some pore-forming and nano-architecting strategies show promises to effectively buffer the volume change, other parameters essential for practical electrode fabrication, such as compaction density, are often compromised. Here we propose a new in situ Mg doping strategy to form closed-nanopore structure into a micron-sized SiO particle at a high bulk density.

A Fast-Charge Graphite Anode with a Li-Ion-Conductive, Electron/Solvent-Repelling Interface.

Graphite has been serving as the key anode material of rechargeable Li-ion batteries, yet is difficultly charged within a quarter hour while maintaining stable electrochemistry. In addition to a defective edge structure that prevents fast Li-ion entry, the high-rate performance of graphite could be hampered by co-intercalation and parasitic reduction of solvent molecules at anode/electrolyte interface. Conventional surface modification by pitch-derived carbon barely isolates the solvent and electrons, and usually lead to inadequate rate capability to meet practical fast-charge requirements.

A Fully Amorphous, Dynamic Cross-Linked Polymer Electrolyte for Lithium-Sulfur Batteries Operating at Subzero-Temperatures.

Solid-state lithium-sulfur batteries have shown prospects as safe, high-energy electrochemical storage technology for powering regional electrified transportation. Owing to limited ion mobility in crystalline polymer electrolytes, the battery is incapable of operating at subzero temperature. Addition of liquid plasticizer into the polymer electrolyte improves the Li-ion conductivity yet sacrifices the mechanical strength and interfacial stability with both electrodes.

Refined Electrolyte and Interfacial Chemistry toward Realization of High-Energy Anode-Free Rechargeable Sodium Batteries.

Anode-free rechargeable sodium batteries represent one of the ultimate choices for the 'beyond-lithium' electrochemical storage technology with high energy. Operated based on the sole use of active Na ions from the cathode, the anode-free battery is usually reported with quite a limited cycle life due to unstable electrolyte chemistry that hinders efficient Na plating/stripping at the anode and high-voltage operation of the layered oxide cathode. A rational design of the electrolyte toward improving its compatibility with the electrodes is key to realize the battery.

Potential Controllable Redox Couple for Mild and Efficient Lithium Recovery from Spent Batteries.

The prosperity of the lithium-ion battery market is dialectically accompanied by the depletion of corresponding resources and the accumulation of spent batteries. It is an urgent priority to develop green and efficient battery recycling strategies for helping ease resources and environmental pressures at the current stage. Here, we propose a mild and efficient lithium extracting strategy based on potential controllable redox couples.

High-Performance Quasi-Solid-State Lithium-Sulfur Battery with a Controllably Solidified Cathode-Electrolyte Interface.

Lithium-sulfur batteries are considered a promising "beyond Li-ion" energy storage technology. Currently, the practical realization of Li-S batteries is plagued by rapid electrochemical failure of S cathodes due to aggravated polysulfide dissolution and shuttle in the conventional liquid ether-based electrolytes. A gel polymer electrolyte obtained by in situ polymerization of liquid electrolyte solvent at the cathode-electrolyte interface has been proven an effective strategy to prevent polysulfide shuttle.

Concentration-Gradient Nb-Doping in a Single-Crystal LiNiCoMnO Cathode for High-Rate and Long-Cycle Lithium-Ion Batteries.

Single-crystalline nickel-rich layered oxides are promising cathode materials for building high-energy lithium-ion batteries because of alleviated particle cracking and irreversible phase transitions upon cycling, compared with their polycrystalline counterparts. Under a high state of charge, parasitic reactions tend to occur at the cathode-electrolyte interface, which could result in sluggish Li-ion diffusion kinetics and quickly faded electrochemical performance of cathodes. In this work, a concentration-gradient niobium-doping strategy was applied to modify the single-crystal LiNiCoMnO cathode, with Nb concentration decreasing linearly from the surface to the core of the particle.

A Self-Reconfigured, Dual-Layered Artificial Interphase Toward High-Current-Density Quasi-Solid-State Lithium Metal Batteries.

The uncontrollable dendrite growth and unstable solid electrolyte interphase have long plagued the practical application of Li metal batteries. Herein, a dual-layered artificial interphase LiF/LiBO-Ag is demonstrated that is simultaneously reconfigured via an electrochemical process to stabilize the lithium anode. This dual-layered interphase consists of a heterogeneous LiF/LiBO glassy top layer with ultrafast Li-ion conductivity and lithiophilic Li-Ag alloy bottom layer, which synergistically regulates the dendrite-free Li deposition, even at high current densities.

Mitigating Swelling of the Solid Electrolyte Interphase using an Inorganic Anion Switch for Low-temperature Lithium-ion Batteries.

In overcoming the Li desolvation barrier for low-temperature battery operation, a weakly-solvated electrolyte based on carboxylate solvent has shown promises. In case of an organic-anion-enriched primary solvation sheath (PSS), we found that the electrolyte tends to form a highly swollen, unstable solid electrolyte interphase (SEI) that shows a high permeability to the electrolyte components, accounting for quickly declined electrochemical performance of graphite-based anode. Here we proposed a facile strategy to tune the swelling property of SEI by introducing an inorganic anion switch into the PSS, via LiDFP co-solute method.

A smart risk-responding polymer membrane for safer batteries.

Safety concerns related to the abuse operation and thermal runaway are impeding the large-scale employment of high-energy-density rechargeable lithium batteries. Here, we report that by incorporating phosphorus-contained functional groups into a hydrocarbon-based polymer, a smart risk-responding polymer is prepared for effective mitigation of battery thermal runaway. At room temperature, the polymer is (electro)chemically compatible with electrodes, ensuring the stable battery operation.