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Integrating a battery‐type electrode to build a hybrid supercapacitor is a promising approach to improve the overall energy density of a supercapacitor‐type energy storage device without sacrificing its power output. However, this strategy is usually achieved at the expense of cycling lifespan. In this work, a hybrid supercapacitor comprising Zn foil and porous carbon derived from chemical activated graphene (aMEGO) is developed, and the trade‐off between energy density and cycling life is well‐balanced by the utilization of 3 m Zn(CF3SO3)2 electrolyte with high Zn stripping/plating efficiency. Such a hybrid supercapacitor demonstrates an energy density of 106.3 Wh kg−1 and a power density of 31.4 kW kg−1, and significantly a wide operation voltage of 1.9 V is achieved in aqueous electrolyte. Benefitting from the high Zn stripping/plating efficiency, the Zn‐aMEGO hybrid‐supercapacitor also exhibits an ultralong cycling life up to 80 000 cycles with capacity retention of 93%, which is comparable to that of conventional electrochemical double‐layer capacitors.

Metallic lithium (Li) is a promising anode material for next-generation rechargeable batteries. However, the dendrite growth of Li and repeated formation of solid electrolyte interface during Li plating and stripping result in low Coulombic efficiency, internal short circuits, and capacity decay, hampering its practical application. In the development of stable Li metal anode, the current collector is recognized as a critical component to regulate Li plating. In this work, a lithiophilic Cu-CuO-Ni hybrid structure is synthesized as a current collector for Li metal anodes. The low overpotential of CuO for Li nucleation and the uniform Li ion flux induced by the formation of Cu nanowire arrays enable effective suppression of the growth of Li dendrites. Moreover, the surface Cu layer can act as a protective layer to enhance structural durability of the hybrid structure in long-term running. As a result, the Cu-CuO-Ni hybrid structure achieves a Coulombic efficiency above 95% for more than 250 cycles at a current density of 1 mA cm and 580 h (290 cycles) stable repeated Li plating and stripping in a symmetric cell.

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High-performance binder-free hierarchical VS2 electrodes with commercial level mass loading were achieved for aqueous Zn-ion batteries.