20:T455,Abstract 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(CF 3 SO 3 ) 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.21:T42a,Zinc ion hybrid capacitors (ZIHCs) are promising energy storage devices for emerging flexible electronics, but they still suffer from trade-off in energy density and cycling life. Herein, we show that such a dilemma can be well-addressed by deploying ZnCl₂ based electrolytes. Combining experimental studies and density functional theory (DFT) calculations, for the first time, we demonstrate an intriguing chloride ion (Cl^- ) facilitated desolvation mechanism in hydrated [ZnCl]⁺ (H₂ O)_n-1 (with n=1-6) clusters. Based on this mechanism, a water-in-salt type hydrogel electrolyte filled with ZnCl₂ was developed to concurrently improve the energy storage capacity of porous carbon materials and the reversibility of Zn metal electrode. The resulting ZIHCs deliver a battery-level energy density up to 217 Wh kg^-1 at a power density of 450 W kg^-1 , an unprecedented cycling life of 100 000 cycles, together with excellent low-temperature adaptability and mechanical flexibility.22:T465,Abstract Although current energy storage devices are limited by their own shortcomings, their merits such as superior power density and cycling stability for supercapacitors (SCs), and high energy density for batteries cannot be ignored either. Constructing hybrid SCs (HSCs) with capacitor‐type electrodes and battery‐type electrodes can combine the advantages of SCs and batteries. Herein, a zinc‐ion HSC (ZHSC) is fabricated with a porous 3D MXene (Ti 3 C 2 T x )‐reduced graphene oxide aerogel cathode and zinc foil anode for the first time. As a result, the ZHSC exhibits excellent electrochemical performance with a high specific capacitance of 128.6 F g −1 at a current density of 0.4 A g −1 and a high energy density of 34.9 Wh kg −1 at a power density of 279.9 W kg −1 . More importantly, after 75 000 charge and discharge cycles at a current density of 5 A g −1 , the capacitance retention is still above 95% of the initial capacitance. This work provides a new way of thinking for developing high‐performance energy storage devices with superior energy, power density, and ultralong cycle life.

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