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Lithium transition metal oxide layers, Li[Ni1−x−yCox(Mn and/or Al)y]O2, are widely used and mass-produced for current rechargeable battery cathodes. Development of cathode materials has focused on increasing the Ni content by simply controlling the chemical composition, but as the Ni content has almost reached its limit, a new breakthrough is required. In this regard, microstructural modification is rapidly emerging as a prospective approach, namely in the production of nano-rod layered cathode materials. A comprehensive review of the physicochemical properties and electrochemical performances of cathodes bearing the nano-rod microstructure is provided herein. A detailed discussion is regarding the structural stability of the cathode, which should be maximized to suppress microcrack formation, the main cause of capacity fading in Ni-rich cathode materials. In addition, the morphological features required to achieve optimal performance are examined. Following a discussion of the initial nano-rod cathodes, which were based on compositional concentration gradients, the preparation of nano-rod cathodes without the inclusion of a concentration gradient is reviewed, highlighting the importance of the precursor. Subsequently, the challenges and advances associated with the nano-rod structure are discussed, including considerations for synthesizing nano-rod cathodes and surface shielding of the nano-rod structure. It goes on to cover nano-rod cathode materials for next-generation batteries (e.g., all-solid-state, lithium-metal, and sodium-ion batteries), inspiring the battery community and other materials scientists looking for clues to the solution of the challenges that they encounter. [ABSTRACT FROM AUTHOR]

"Anodeless" electrodes for all‐solid‐state batteries (ASSBs) have been attracting attention as a solution for achieving high energy density. Recent studies on anodeless electrodes have shown improvements in cycle life and energy density through the stabilization of plated lithium (Li) using Li‐soluble metals (e.g., Ag, Zn, etc.). In this study, magnesium‐based materials (MgF2@C) are introduced for use as an anodeless electrode. Nanodot magnesium fluoride (MgF2) is synthesized onto a carbon black surface via sonochemical synthesis. MgF2 is converted to a Mg‐Li alloy and LiF during lithiation. The Mg‐Li alloy from the MgF2@C anodeless electrode reduces lithiation overpotential and provides a uniform and dense Li layer between the current collector and the anodeless electrode. The ASSB cell assembled with the MgF2@C anodeless electrode exhibits 81.4% capacity retention after 200 cycles at 30 °C. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) have garnered attention from both academia and industry because they can achieve high energy densities (>400 Wh kg–1), which are difficult to achieve in commercially available lithium‐ion batteries. As a preparation step for practically utilizing LSBs, there is a problem, wherein battery cycle life rapidly reduces as the loading level of the sulfur cathode increases and the electrode area expands. In this study, a separator coated with boehmite on both sides of polyethylene (hereinafter denoted as boehmite separator) is incorporated into a high‐loading Li‐S pouch battery to suppress sudden capacity drops and achieve a longer cycle life. We explore a phenomenon by which inequality is generated in regions where an electrochemical reaction occurs in the sulfur cathode during the discharging and charging of a high‐capacity Li‐S pouch battery. The boehmite separator inhibits the accumulation of sulfur‐related species on the surface of the sulfur cathode to induce an even reaction across the entire cathode and suppresses the degradation of the Li metal anode, allowing the pouch battery with an areal capacity of 8 mAh cm–2 to operate stably for 300 cycles. These results demonstrate the importance of customizing separators for the practical use of LSBs. [ABSTRACT FROM AUTHOR]

Developing suitable cathodes with high capacity and high power is challenging for K‐ion batteries. Herein, electrochemical K‐ion storage properties of the layered‐type K0.4V2O5 (KVO) cathode by incorporating divalent strontium ions (Sr2+) into its crystal structure are enhanced. Divalent strontium ions (1.18 Å) are preferentially incorporated into the octahedrally coordinated K (1.38 Å) layers due to the similar ionic size compared to V4+ (0.58 Å). The introduction of 3 mmol of Sr ions in the KVO crystal improves electrical conductivity and reduces K‐ion diffusion energy barriers. In addition, the strong Sr2+ and O2− interaction acts as a structural pillar, suppressing irreversible phase transition during charge–discharge process. Multi‐physics simulations clearly confirm that the K0.34Sr0.03V2O5 (KS3VO) cathode exhibits a more uniform K‐ion distribution and enhanced reactions of K‐ions compared to the KVO cathode at various depths of discharge. As a result, the KS3VO cathode demonstrates improved reversible capacity, cycling stability, and power capability over the KVO cathode in a K‐ion cell. Synchrotron X‐ray analysis reveals how Sr substitution enhances the electrochemical K‐ion storage properties of the KS3VO cathode. In addition, the KS3VO cathode exhibits superior thermal stability and cycling stability in a full cell coupled with a hard carbon anode compared to the KVO cathode. [ABSTRACT FROM AUTHOR]

Abundant and economical sodium (Na) metal batteries promise superior energy densities compared to lithium‐ion batteries; however, they face commercialization challenges owing to problematic interfacial reactions leading to dendrite formation during cycling. This paper reports the ultra‐long and rapid operation of Na metal batteries enabled by the introduction of a vinylpyrrolidone (VP)‐based multifunctional interface stabilizer in the electrolyte. The VP electrolyte additive provides benefits such as surface flattening, durable solid electrolyte interphase layer formation, preservation of fresh Na, and acceleration of horizontal crystal growth along the (110) plane. Symmetric Na–Na cells with the stabilizer exhibit notably stable operation for over 5 000 cycles at a high current density of 5 mA cm−2, surpassing previous research. Performance improvement is also demonstrated in a full‐cell configuration with an Na3V2(PO4)2O2F cathode. This approach offers a promising solution for achieving performance levels comparable to lithium‐ion batteries in Na metal battery technology. [ABSTRACT FROM AUTHOR]

With the increasing global demand for energy and the continuous destruction of the environment, the demand for sustainable green development is becoming increasingly urgent. However, the development and renewal of new-energy vehicles and various electronic devices have resulted in an increasing number of waste batteries. The key to the sustainable development of today's battery industry is the efficient and green recycling of valuable waste batteries, especially metal resources. Recycling batteries cannot only halt the environmental pollution caused by batteries but also transform waste into resources for reuse. Current mainstream recycling methods, such as traditional hydrometallurgy and pyrometallurgy, can cause substantial environmental pollution. We systematically reviewed the recent research progress on using green solvents to recycle battery metal materials. We summarized the characteristics and efficiency of each recycling process in detail to provide an effective reference for the future development of green solvents in the battery recycling industry. Finally, the prospects for developing battery technology and green solvent systems for recycling battery metal materials are discussed, and current considerations in the field of battery recycling and possibilities for each green solvent hybrid system are proposed. [ABSTRACT FROM AUTHOR]

Alloying‐type metallic tin is perceived as a potential anode material for K‐ion batteries owing to its high theoretical capacity and reasonable working potential. However, pure Sn still face intractable issues of inferior K+ storage capability owing to the mechanical degradation of electrode against large volume changes and formation of intermediary insulating phases K4Sn9 and KSn during alloying reaction. Herein, the TiC/C–carbon nanotubes (CNTs) is prepared as an effective buffer matrix and composited with Sn particles (Sn–TiC/C–CNTs) through the high‐energy ball‐milling method. Owing to the conductive and rigid properties, the TiC/C–CNTs matrix enhances the electrical conductivity as well as mechanical integrity of Sn in the composite material and thus ultimately contributes to performance supremacy in terms of electrochemical K+ storage properties. During potassiation process, the TiC/C–CNTs matrix not only dissipates the internal stress toward random radial orientations within the Sn particle but also provides electrical pathways for the intermediate insulating phases; this tends to reduce microcracking and prevent considerable electrode degradation. [ABSTRACT FROM AUTHOR]