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Sodium-sulfur batteries operating at ambient temperature are being extensively studied because of the high theoretical capacity and abundant resources, yet the long-chain polysulfides' shuttle effect causes poor cycling performance of Na− S batteries. We report an annealing/etching method to converse low-cost wheat bran to a 3D honeycomb-like carbon with abundant micropores (WBMC), which is smaller than S 8 molecular size (∼0.7 nm). Thus, the microporous structure could only fill small molecular sulfur (S 2−4 ). The micropores made sulfur a one-step reaction without the shuttle effect due to the formed short-chain polysulfides being insoluble. The WBMC@S exhibits an excellent initial capacity (1413 mAh g −1 ) at 0.2 C, outstanding cycling performance (822 mAh g −1 after 100 cycles at 0.2 C), and high rate performance (483 mAh g −1 at 3.0 C). The electrochemical performance proves that the steric confinement of micropores effectively terminates the shuttle effect.

When compared to expensive lithium metal, the metal sodium resources on Earth are abundant and evenly distributed. Therefore, low-cost sodium-ion batteries are expected to replace lithium-ion batteries and become the most likely energy storage system for large-scale applications. Among the many anode materials for sodium-ion batteries, hard carbon has obvious advantages and great commercial potential. In this review, the adsorption behavior of sodium ions at the active sites on the surface of hard carbon, the process of entering the graphite lamellar, and their sequence in the discharge process are analyzed. The controversial storage mechanism of sodium ions is discussed, and four storage mechanisms for sodium ions are summarized. Not only is the storage mechanism of sodium ions (in hard carbon) analyzed in depth, but also the relationships between their morphology and structure regulation and between heteroatom doping and electrolyte optimization are further discussed, as well as the electrochemical performance of hard carbon anodes in sodium-ion batteries. It is expected that the sodium-ion batteries with hard carbon anodes will have excellent electrochemical performance, and lower costs will be required for large-scale energy storage systems.

In recent years, the driving range of electric vehicles (EVs) has been dramatically improved. But the large‐scale adoption of EVs still is hindered by long charging time. The high‐energy LIBs are unable to be safely fast‐charged due to their electrode materials with unsatisfactory rate performance. Thus it is necessary to summarize the properties of cathode and anode materials of fast‐charging LIBs. In this review, we summarize the background, the fundamentals, electrode materials and future development of fast‐charging LIBs. First, we introduce the research background and the physicochemical basics for fast‐charging LIBs. Second, typical cathode materials of LIBs and the method to enhancing their fast‐charging properties are discussed. Third, the anode materials of LIBs and the strategies for improving their fast‐charging performance are analyzed. Finally, the future development of the cathode materials in fast‐charging LIBs is prospected.