Voltage-Induced Bromide Redox Enables Capacity Restoration of Fast-Charging Batteries.

Fast-charging lithium-ion batteries (LIBs) are essential for electric vehicles (EVs) to compete with conventional gasoline ones in terms of charging viability, yet the aggressive capacity drop in fast-charging scenarios gives rise to concerns regarding durability and sustainability. Herein, it is clarified that for fast-charging batteries, the excessive lithium (Li) plating on graphite anode inevitably brings capacity fading, and the concurrent accumulation of LiO-dominant passivation species that form dead Li is the main reason for their poor rechargeability. To refresh the passivated graphite, a voltage-induced activation mechanism is developed to leverage bromide (Br/Br ) redox couple for LiO and isolated Li activation in situ.

Optimizing Oxygen Redox Activity by Local Chemical Disorder toward Robust Co-Free Li-Rich Cathode with High Voltage Stability.

Despite extensive investigation on the lattice oxygen redox (LOR) in Li-rich cathodes, significant challenges remain in utilizing LOR activity without compromising structural and electrochemical stability. Related breakthroughs are hindered by the lack of understanding regarding how different LOR activity influences the structural evolution and electrochemical stability, and what is the optimal LOR activity. Herein, the degree of LOR activity is successfully regulated from 22% to 92% in Co-free Li-rich cathodes (LiMnNiO) by controlling local chemical disorder, and the relationship between LOR activity and cycling stability is revealed.

Practical H supply from ammonia borane enabled by amorphous iron domain.

Efficient catalysis of ammonia borane (AB) holds potential for realizing controlled energy release from hydrogen fuel and addressing cost challenges faced by hydrogen storage. Here, we report that amorphous domains on metallic Fe crystal structures (R-FeO Foam) can achieve AB catalytic performances and stability (turnover frequency (TOF) of 113.6 min, about 771 L H in 900 h, and 43.

Zinc Dicyanamide: A Potential High-Capacity Negative Electrode for Li-Ion Batteries.

We demonstrate that the β-polymorph of zinc dicyanamide, Zn[N(CN)], can be efficiently used as a negative electrode material for lithium-ion batteries. Zn[N(CN)] exhibits an unconventional increased capacity upon cycling with a maximum capacity of about 650 mAh·g after 250 cycles at 0.5C, an increase of almost 250%, and then maintaining a large reversible capacity of more than 600 mAh·g for 150 cycles.

First-Principles Study on Polymer Electrolyte Interface Engineering for Lithium Metal Anodes.

Modifying the interface between the lithium metal anode (LMA) and the electrolyte is crucial for achieving high-performance lithium metal batteries (LMBs). Recent research indicates that altering Li-metal interfaces with polymer coatings is an effective approach to extend LMBs' cycling lifespan. However, the physical properties of these polymer-Li interfaces have not yet been fully investigated.

Formation of 2D Amorphous Lithium Sulfide Enabled by MoC Clusters Loaded Carbon Scaffold for High-Performance Lithium Sulfur Batteries.

Lithium-sulfur (Li-S) batteries, operated through the interconversion between sulfur and solid-state lithium sulfide, are regarded as next-generation energy storage systems. However, the sluggish kinetics of lithium sulfide deposition/dissolution, caused by its insoluble and insulated nature, hampers the practical use of Li-S batteries. Herein, leaf-like carbon scaffold (LCS) with the modification of MoC clusters (MoC@LCS) is reported as host material of sulfur powder.

Achieving Highly Stable Zn Metal Anodes at Low Temperature via Regulating Electrolyte Solvation Structure.

Zinc metal is an attractive anode material for rechargeable aqueous Zn-ion batteries (ZIBs). However, the dendrite growth, water-induced parasitic reactions, and freezing problem of aqueous electrolyte at low temperatures are the major roadblocks that hinder the widely commercialization of ZIBs. Herein, tetrahydrofuran (THF) is proposed as the electrolyte additive to improve the reversibility and stability of Zn anode.

Design principles of heterointerfacial redox chemistry for highly reversible lithium metal anode.

High electrochemical reversibility is required for the application of high-energy-density lithium (Li) metal batteries; however, inactive Li formation and SEI (solid electrolyte interface)-instability-induced electrolyte consumption cause low Coulombic efficiency (CE). The prior interfacial chemical designs in terms of alloying kinetics have been used to enhance the CE of Li metal anode; however, the role of its redox chemistry at heterointerfaces remains a mystery. Herein, the relationship between heterointerfacial redox chemistry and electrochemical transformation reversibility is investigated.

Polymer Molecules Adsorption-Induced Zincophilic-Hydrophobic Protective Layer Enables Highly Stable Zn Metal Anodes.

Zn metal, as one of the most promising anode materials for aqueous batteries, suffers from uncontrollable dendrite growth and water-induced parasitic reactions, which drastically compromise its cycle life and Coulombic efficiency (CE). Herein, a nonionic amphipathic additive Tween-20 (TW20) is proposed that bears both zincophilic and hydrophobic units. The zincophilic segment of TW20 preferentially adsorbs on the Zn anode, while the hydrophobic segment is exposed on the electrolyte side, forming an electrolyte-facing hydrophobic layer that shields the anode from active water molecules.

Structure-Property Interplay Within Microporous Manganese Dioxide Tunnels For Sustainable Energy Storage.

Tunnel-structured manganese dioxides (MnO ), also known as octahedral molecule sieves (OMS), are widely studied in geochemistry, deionization, energy storage and (electro)catalysis. These functionalities originate from their characteristic sub-nanoscale tunnel framework, which, with a high degree of structural polymorphism and rich surface chemistry, can reversibly absorb and transport various ions. An intensive understanding of their structure-property relationship is prerequisite for functionality optimization, which has been recently approached by implementation of advanced (in situ) characterizations providing significant atomistic sciences.

Atomic-level polarization in electric fields of defects for electrocatalysis.

The thriving field of atomic defect engineering towards advanced electrocatalysis relies on the critical role of electric field polarization at the atomic scale. While this is proposed theoretically, the spatial configuration, orientation, and correlation with specific catalytic properties of materials are yet to be understood. Here, by targeting monolayer MoS rich in atomic defects, we pioneer the direct visualization of electric field polarization of such atomic defects by combining advanced electron microscopy with differential phase contrast technology.

Sulfur-Assisted Surface Modification of Lithium-Rich Manganese-Based Oxide toward High Anionic Redox Reversibility.

Energy storage via anionic redox provides extra capacity for lithium-rich manganese-based oxide cathodes at high voltage but causes gradual structural collapse and irreversible capacity loss with generation of O (0 ≤ n < 2) species upon deep oxidation. Herein, the stability and reversibility of anionic redox reactions are enhanced by a simple sulfur-assisted surface modification method, which not only modulates the material's energy band allowing feasible electron release from both bonding and antibonding bands, but also traps the escaping O via an as-constructed SnS O coating layer and return them to the host lattice upon discharge. The regulation of anionic redox inhibits the irreversible structural transformation and parasitic reactions, maintaining the specific capacity retention of as-modified cathode up to 94% after 200 cycles at 100 mA g , along with outstanding voltage stability.