LiFePO₄emerges as a viable alternative to cobalt‐containing cathodes, such as Li[Ni_1–x–yMn_xCo_y]O₂and Li[Ni_1−x−yCo_xAl_y]O₂. As Fe is abundant in nature, LiFePO₄is a low‐cost material. Moreover, stable structure of LiFePO₄imparts long service life and thermal stability. However, the practical implementation of LiFePO₄cathode in energy storage devices is impeded by its low energy density and high ionic/electrical resistance. Herein, the LiFePO₄electrode with high active material loading and low ionic/electrical resistance through the dry process is reported for the first time. The dry process not only enables the uniform distribution of the polymeric binders and conductive additives within the thick electrode but also inhibits the formation of cracks. Furthermore, the bridge‐like connection of polytetrafluoroethylene facilitates the insertion and extraction of Li ions to the LiFePO₄crystal. Hence, the dry‐processed LiFePO₄electrode with high areal capacity (7.8 mAh cm⁻²) exhibits excellent cycle stability over 300 cycles in full‐cell operation. In addition, it is demonstrated that the estimated energy density of prismatic cell with the dry‐processed LiFePO₄electrode is competitive with state‐of‐the‐art Li[Ni_1–x–yMn_xCo_y]O₂‐based battery.

Metallic Li has caught the attention of researchers studying future anodes for next-generation batteries, owing to its attractive properties: high theoretical capacity, highly negative standard potential, and very low density. However, inevitable issues, such as inhomogeneous Li deposition/dissolution and poor Coulombic efficiency, hinder the pragmatic use of Li anodes for commercial rechargeable batteries. As one of viable strategies, the surface functionalization of polymer separators has recently drawn significant attention from industries and academics to tackle the inherent issues of metallic Li anodes. In this article, separator-coating materials are classified into five or six categories to give a general guideline for fabricating functional separators compatible with post-lithium-ion batteries. The overall research trends and outlook for surface-functionalized separators are reviewed.

Recent advancements in inorganic solid electrolytes (ISEs), achieving sodium (Na)‐ion conductivities exceeding 10 ^‐2 S cm^‐1 at room temperature (RT), have generated significant interest in the development of solid‐state sodium batteries (SSSBs). However, the ISEs face challenges such as their limited electrochemical stability windows (ESWs) and compatibility issues with high‐capacity, high‐voltage cathode materials and Na metal anodes. The success of high‐performance SSSBs hinges on developing ideal ISEs that deliver high Na⁺ ion conductivities, robust chemical and electrochemical stability, and well constructed electrode/ISE interfaces. This review explores the fundamental principles and strategies to optimize SSSB performance by addressing issues related to ISEs and their interfaces, emphasizing that many interfacial challenges are intrinsically linked to ISE properties. It highlights recent advancements in ISE research, including the mechanisms of Na‐ion conduction and the key factors influencing it, such as crystal structure, lattice dynamics, point defects, and grain boundaries. It also discusses prototyping strategies for cell design from the perspectives of material and defect chemistry. Additionally, the review identifies key challenges and future opportunities for advancing SSSBs and provides rational solutions to guide future research toward the practical realization of high‐performance SSSBs.Keywords: Solid‐state sodium batteries; Inorganic solid electrolytes; Interfacial mechanism; Electrochemical stability window; Ionic conductivity; Modification strategies