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High‐power‐density rechargeable batteries are highly indispensable for power‐intensive application scenarios, such as vehicle start‐stop system and grid‐level frequency regulation. However, realizing high‐power‐density alkali‐ion batteries is challenging especially at low temperatures, as undesirable alkali metal plating tends to occur more easily on the anode surface due to the increased electrochemical impedance and polarization. Herein, a low‐temperature, high‐power‐density rechargeable Na3V2(PO4)3 ||hard carbon (HC) sodium‐ion full battery without Na plating is realized by electrolyte regulation. The designed high‐solvation‐entropy electrolyte enables a high ionic conductivity of 13.87 mS cm−1 at −40 °C. More importantly, the enhanced contact‐ion pairs solvation structure induces an anion‐derived, thin, NaF‐rich solid electrolyte interface (SEI) on HC anodes with low interfacial resistance to ensure facile Na+ diffusion through the SEI. Consequently, the assembled sodium‐ion full battery demonstrates a record‐high power density of 1132.31 W kg−1 (with an energy density of 61.94 Wh kg−1) at −40 °C and 13372.56 W kg−1 (132.83 Wh kg−1) at 25 °C (based on total mass of the active materials on anode and cathode). This work will expedite the development of sodium‐ion batteries for power‐intensive applications in extreme environments. [ABSTRACT FROM AUTHOR]

Widespread integration of carbon‐based membranes into prevailing fields like energy storage and material engineering is thwarted by a lack of functionality, customization, and compatibility, making the development of such carbon‐based membranes urgency yet challenging. Herein, a "graphene bubble bridging" strategy is adopted to fabricate the multifunctional carbon fiber membrane, in which graphene bubbles with optimized assembling not only endow the carbon fiber with superior flexibility and integrity by embedded bridging function, but also enhance the fast electron transport capability and electrolyte wettability. Few‐layer MoSSe nanosheets with expanded interlayer spacing as a typical energy storage material contribute to plentiful ion intercalation/deintercalation that can be well buffered within the robust fibers. The interlaced carbon fibers enable a self‐supporting framework that ensures good conductivity and mechanical stability as well. Such functional, customized, and compatible membranes with synergies can boost the attributes of advanced K+ storage devices, such as flexible K‐ion capacitors and K‐based dual‐ion batteries. This work can afford new insights for designing flexible electrode in the energy storage field, as well as various types of conformations that can bring more opportunities on developing flexible functional membranes for other fields (e.g., catalysts, electromagnetic shielding). [ABSTRACT FROM AUTHOR]

Lithium ion micro capacitors (LIMCs) demonstrate competitive advantages of simultaneously high energy/power densities and long cycle life over many other micro supercapacitors and micro batteries. However, these performances are significantly determined by the carbon anode with fast Li+ storage kinetics. Herein, a design strategy at the precursor side of a typical porous aromatic framework‐5 (PAF‐5) from the carbon bonding levels is proposed, and coupling with the post pyrolysis, the sp2/sp3 domains ratio, interlayer spacing, and pore structure of derived carbons can be synergistically balanced. The inherited sp2 domains and porous structure from PAF‐5 endow the derived carbon with high electron transport capability and fast Li+ adsorption capacity. Meanwhile, the developed sp3 domains and enlarged interlayer spacing also enable abundant and fast Li+ intercalation contribution, giving rise to a superior rate capability (141.9 mAh g−1 at 4 A g−1) that is 13 times better than a commercial graphite anode. A flexible LIMCs based on this carbon anode are fabricated, and simultaneously high energy/power densities (71.1 mWh cm−3/1.9 W cm−3), long cycle life (94.7% after 6,000 cycles), and flexibility are achieved, demonstrating a great feasibility of designed PAFs as the trimmed carbon anode precursors for high performance Li+ storage. [ABSTRACT FROM AUTHOR]