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Na‐ion batteries have attracted much attention as one of the most promising alternatives to lithium‐ion batteries. Na3V2(PO4)3 has been widely investigated as a cathode material for Na‐ion batteries because of its high structural and thermal stability, leading to high cycling performance and safety. The cathode material also possesses a three‐dimensional open framework and consequently provides high ionic conductivity, as well as high‐rate capability. However, the cathode type experiences poor electronic conductivity, affecting its electrochemical properties. It is well established that preparation methods have remarkable effects on the crystal structure and morphology of electrode materials, altering their electrochemical performance. Thus, this work focuses on a comparative study of the morphology, structures, electrochemical performance, and kinetic properties of Na3V2(PO4)3/C cathodes prepared by sol‐gel and solid‐state methods, which are simple and scalable. The results reveal that sol‐gel and solid‐state reaction processes provide Na3V2(PO4)3/C cathode materials with different structural and morphological characteristics, significantly affecting their electrochemical performance and kinetic properties. This is a crucial key to finding a proper synthesis method to achieve Na3V2(PO4)3/C with high performance for commercial large‐scale production. [ABSTRACT FROM AUTHOR]

Lithium metal orthosilicates, Li2MSiO4 (M = Fe, Mn, Co, Ni, and their mixtures), have been attracting significant attention as alternative cathodes for next‐generation high energy Li‐ion batteries (LIBs). The high capacity of these cathodes is attributed to two reversible transitions, those of Li2MSiO4 to LiMSiO4 and LiMSiO4 to MSiO4 phases involving two Li+ ions per mole. However, due to their complex structures and phase transformation behaviors, these materials are not yet available for practical commercial applications. Rate capability is one of the most important properties of cathode materials that are affected by phase transformations. This review will comprehensively summarize the current knowledge of the rate‐dependent phase transformations of Li2MSiO4 materials based on various characterization tools to facilitate future developments of these high potential cathode materials for future LIBs. [ABSTRACT FROM AUTHOR]

Silica is a promising anode material for high‐energy lithium‐ion batteries (LIBs), but it suffers from several problems. The main issue is low electrical conductivity, which limits its practical applications. Fabricating silica–carbon nanocomposites (C/SiO2) can significantly enhance the electrochemical performance of these materials. In this work, the authors perform first principles calculations to investigate the interfacial properties and electronic structure between carbon and small Si‐based molecules. The simulations suggest that C/SiO2 and C/SiO interfaces facilitate the lithiation process, providing additional lithium storage pathways in addition to the typical phase transitions of SiO2 and SiO. In addition, a simple production and ready to scale‐up method is proposed to fabricate a nanocomposite possessing rich C/SiOx (1 ≤ x ≤ 2) interfaces. The resulting nanocomposite anode has a stable capacity of ~650 mAh g‐1 at a current density of 1 A g‐1 after 1500 cycles with >95% capacity retention. This work provides a better understanding of the Li ion storage mechanisms of C/SiOx. Adding carbon not only increases electrical conductivity and strength, but also provides new pathways for Li‐ion transport through their interfaces contributing to the enhanced stability and electrochemical properties of inexpensive non‐conducting/oxide‐based energy storage materials. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) are one of the most promising next‐generation batteries in achieving the high energy density because of their low reduction potential and large theoretical capacity. However, since the birth of the first rechargeable lithium batteries, the uncontrolled lithium growth and the accompanying side‐reactions have seriously hampered the development of LMBs. Decades of research efforts have extensively studied the mechanisms governing these issues; however, the practical adoption of lithium metal in batteries is still yet to come. Recent advancements of the characterization tools offer unprecedentedly detailed views of the behavior of lithium metals in the electrochemical cells, which have been considered challenging due to the intrinsic instability of lithium metal. This new capability elucidates the stripping and deposition nature of lithium metal more closely, thus revealing what had been overlooked or remained unseen. Herein, recent advances in characterization and analysis tools for studies of LMBs are summarized, and what new findings and insights have been obtained in the understanding of LMBs are discussed. It is believed that this report will aid in addressing the opportunities and remaining challenges in the research of lithium metal by giving a comprehensive perspective on the current advanced suits of characterization tools, therefore expediting the development of practical LMBs. [ABSTRACT FROM AUTHOR]