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An aqueous Zn/VS2 battery is designed, which consists of a VS2 cathode, a zinc anode, and a mild ZnSO4 aqueous electrolyte. The battery delivers a high capacity, and exhibits long‐term cyclic stability due to the large layer spacing and high conductivity of VS2. A reversible insertion/extraction of Zn2+ is observed during the discharge/charge process. [ABSTRACT FROM AUTHOR]

Constructing a self‐buffered nanostructure is demonstrated to be a facile and effective strategy to enhance lithium battery performance. On page 1773 L. Mai and team construct a novel polygonal nanoscroll (PNS) structure via the self‐rolling, Ostwald ripening and scroll‐by‐scroll mechanism. This novel PNS structure offers the robust outer wall and expandable inner space to buffer the swelling stress during Li+ ion intercalation/extraction, which effectively improves the cycling stability. [ABSTRACT FROM AUTHOR]

An elaborate balance between porosity and density of carbon materials is a prerequisite for achieving high volumetric energy storage in carbon-based supercapacitors. Three-dimensional graphene aerogels have interconnected and continuous pores, but suffer from unsatisfactory volumetric performances for their low densities. Herein, we report an ethanol-mediated capillary evaporation technique to prepare a dense and N/O/P-doped graphene xerogel (Ethyl-NPGX) for supercapacitor electrodes. The Ethyl-NPGX is featured with high compaction density of 1.53 g cm−3, moderate specific surface area of 203.6 m2 g−1, average mesopore diameter of 6.02 nm, and abundant heteroatoms, including 2.1 at% of N, 14.4 at% of O, and 0.2 at% of P. With simultaneously achieved high density and efficient pore utilization brought by profitable surface functionalities, the Ethyl-NPGX exhibits an ultrahigh volumetric capacitance of 413 F cm−3 in a three-electrode system using 6 M KOH electrolyte, which is significantly higher than those of reported graphene-based carbons. Moreover, as-assembled symmetric two-electrode cell delivers an exceptional high volumetric energy density of 25.7 Wh L−1 at 306 W L−1 and an excellent cycling stability with 84.2% capacitance retention after 20000 cycles in aqueous electrolyte. Our work provides a promising strategy to densify porous graphene towards compact energy storage. [Display omitted] • An ethanol-mediated capillary evaporation to densify graphene xerogels. • Porosity and density of graphene xerogel were elaborately balanced. • Profitable surface functionalities improved the inner pore utilization. • An ultrahigh volumetric capacitance of 413 F cm−3 was achieved. [ABSTRACT FROM AUTHOR]