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Lithium metal shows a great advantage as the most promising anode for its unparalleled theoretical specific capacity and extremely low electrochemical potential. However, uncontrolled lithium dendrite growth and severe side reactions of the reactive intermediates and organic electrolytes still limit the broad application of lithium metal batteries. Herein, we propose 4‐nitrobenzenesulfonyl fluoride (NBSF) as an electrolyte additive for forming a stable organic–inorganic hybrid solid electrolyte interphase (SEI) layer on the lithium surface. The abundance of lithium fluoride and lithium nitride can guarantee the SEI layer's toughness and high ionic conductivity, achieving dendrite‐free lithium deposition. Meanwhile, the phenyl group of NBSF significantly contributes to both the chemical stability of the SEI layer and the good adaptation to volume changes of the lithium anode. The lithium–oxygen batteries with NBSF exhibit prolonged cycle lives and excellent cycling stability. This simple approach is hoped to improve the development of the organic–inorganic SEI layer to stabilize the lithium anodes for lithium–oxygen batteries. [ABSTRACT FROM AUTHOR]

Water‐based secondary batteries with multivalent metals anode provide a promising option for energy storage with low cost and high security. However, the electrochemical performance of aqueous Zinc ion batteries (AZIBs) is mainly restricted by problems such as poor reversibility and hydrogen evolution. Herein, an "amphoteric polymer strategy" with buffer‐adsorption mechanism for AZIBs is proposed by introducing poly‐L‐Glutamic Acid (PGA) into the electrolyte. Amphoteric polymer enriched functional carboxyl and amino groups confer high compatibility of the Zn metal anodes as well as the relative stability of the bulk electrolyte pH simultaneously. Partial PGA molecules distributed in bulk electrolyte dynamically dissociate to stabilize pH and correspondingly slow down the generation of inert components, while others specifically adsorbed on zinc foil can relieve electrochemical corrosion and induce dendrite‐free uniform Zn deposition. Consequently, long‐term cycling stability (>1650 h) and high levels of reversibility (Coulombic efficiency>99.5%) of Zn anode are harvested in 2 m ZnSO4 electrolyte with only 0.5 wt% of PGA. In addition, when coupled with Zn0.25V2O5(ZVO) cathode, the full cell exhibits higher capacity retention and less pH fluctuation. This work reveals a novel buffer‐adsorption mechanism offered by amphoteric functional polymer, and provides a new additive design principle for rechargeable AZIBs. [ABSTRACT FROM AUTHOR]

Fe‐based Prussian blue (Fe‐PB) cathode material shows great application potential in sodium (Na)‐ion batteries due to its high theoretical capacity, long cycle life, low cost, and simple preparation process. However, the crystalline water and vacancies of Fe‐PB lattice, the low electrical conductivity, and the dissolution of metal ions lead to limited capacity and poor cycling stability. In this work, a perylene tetracarboxylic dianhydride amine (PTCDA) coating layer is successfully fabricated on the surface of Fe‐PB by a liquid‐phase method. The aminated PTCDA (PTCA) coating not only increases the specific surface area and electronic conductivity but also effectively reduces the crystalline water and vacancies, which avoids the erosion of Fe‐PB by electrolyte. Consequently, the PTCA layer reduces the charge transfer resistance, enhances the Na‐ion diffusion coefficient, and improves the structure stability. The PTCA‐coated Fe‐PB exhibits superior Na storage performance with a first discharge capacity of 145.2 mAh g−1 at 100 mA g−1. Long cycling tests exhibit minimal capacity decay of 0.027% per cycle over 1000 cycles at 1 A g−1. Therefore, this PTCA coating strategy has shown promising competence in enhancing the electrochemical performance of Fe‐PB, which can potentially serve as a universal electrode coating strategy for Na‐ion batteries. [ABSTRACT FROM AUTHOR]

Although biomass‐derived carbon (biochar) has been widely used in the energy field, the relation between the carbonization condition and the physical/chemical property of the product remains elusive. Here, we revealed the carbonization condition's effect on the morphology, surface property, and electrochemical performance of the obtained carbon. An open slit pore structure with shower‐puff‐like nanoparticles can be obtained by finely tuning the carbonization temperature, and its unique pore structure and surface properties enable the Li–O2 battery with cycling longevity (221 cycles with 99.8% Coulombic efficiency at 0.2 mA cm−2 and controlled discharge–charge depths of 500 mAh g−1) and high capacity (16,334 mAh g−1 at 0.02 mA cm−2). This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions, paving the way for future study of energy storage devices. [ABSTRACT FROM AUTHOR]