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Zinc‐ion hybrid supercapacitors (ZHSCs) may be the most promising energy storage device alternatives for portable and large‐scale electronic devices in the future, as they combine the benefits of both supercapacitors and zinc‐ion batteries. Even though many surprise outcomes have been accomplished with ZHSCs, the creation of suitable cathode materials and electrolytes, as well as the enhancement of zinc anodes, continue to be the most difficult obstacles in the development of high‐performance ZHSCs. The low capacitance of the cathode material, poor stability, and low utilization rate of the zinc anode seriously affect the electrochemical performance and application of ZHSCs. Furthermore, parasitic processes in aqueous electrolytes, such as the hydrogen and oxygen evolution reactions might result in low‐voltage windows and unsatisfied cycling performance of the ZHSCs. This review provides a concise summary of the most recent developments and energy storage mechanisms in ZHSCs. Meanwhile, the cathode material design strategy (structural engineering, hybrid‐composite design, heteroatom doping, and so on), the zinc anode design strategy (zinc foil improvement, zinc‐free metal composites, and so on), and the structure–activity relationship of the electrochemical performance of ZHSCs are discussed. Additionally, a summary of the impact of modifications in electrolyte composition on the electrochemical performance of ZHSCs is provided. Finally, this review also discusses the future development direction of ZHSCs. It is anticipated that this evaluation will serve as a helpful reference for the creation of high‐performance ZHSCs, which will hasten the development of these devices.

Lithium (Li) metal batteries (LMBs) have been deemed as the next promising high‐energy battery systems for ultrahigh energy densities. However, serious Li dendrites and low Coulombic efficiency issues still impede the practical application of LMBs. Herein, a common three‐dimensional (3D) copper foam partially decorated by a thin lithiophilic tin (Sn) layer (CF@Sn) has been constructed as the current collector of a Li metal anode. The large Li ions prefer to be induced by a Sn layer to produce Li−Sn alloy and selectively deposit on the alloy layers of the composite matrix. Due to the excellent confinement of the growth of metallic Li, the 3D porous heterogeneous lithiophilic skeleton can effectively improve uniform Li deposition, inhibit Li dendrite formation, reduce electrolyte consumption and enhance the electrochemical performance. The composite matrix leads to a high Coulombic efficiency (98.5%) over 400 cycles and ultrastable Li charging/discharging behavior for 1000 h for the symmetric cell at 1 mA cm−2. For the low energy barrier of alloy layer, small potential polarization (20 mV in symmetric cell) and nucleation overpotential (10.5 mV) can be obtained as expected. Especially, full cells paired with LiFePO4 cathodes and CF@Sn@Li anodes deliver an enhanced rate capability and a great discharging capacity of 140 mAh g−1 with high capacity retention of 95.2% after 300 cycles at 0.5 C. The proposed 3D lithiophilic skeleton demonstrates an effective strategy to realize stable and practical Li metal anodes.

A bipolar fluorinated covalent triazine framework (FCTF) was successfully synthesized by the self-polymerization of tetrafluoroterephthalonitrile and exhibited high reversible capacities, long cyclability as a cathode for lithium ion batteries.

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