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Flexible aqueous zinc‐ion batteries (AZIBs) with high safety and low cost hold great promise for potential applications in wearable electronics, but the strong electrostatic interaction between Zn2+ and crystalline structures, and the traditional cathodes with single cationic redox center remain stumbling blocks to developing high‐performance AZIBs. Herein, freestanding amorphous vanadium oxysulfide (AVSO) cathodes with abundant defects and auxiliary anionic redox centers are developed via in situ anodic oxidation strategy. The well‐designed amorphous AVSO cathodes demonstrate numerous Zn2+ isotropic pathways and rapid reaction kinetics, performing a high reversible capacity of 538.7 mAhg‐1 and high‐rate capability (237.8 mAhg‐1@40Ag‐1). Experimental results and theoretical simulations reveal that vanadium cations serve as the main redox centers while sulfur anions in AVSO cathode as the supporting redox centers to compensate local electron‐transfer ability of active sites. Significantly, the amorphous structure with sulfur chemistry can tolerate volumetric change upon Zn2+/H+ insertion and weaken electrostatic interaction between Zn2+ and host materials. Consequently, the AVSO composites display alleviated structural degradation and exceptional long‐term cyclability (89.8% retention after 20 000 cycles at 40 Ag‐1). This work can be generally extended to various freestanding amorphous cathode materials of multiple redox reactions, inspiring development of designing ultrafast and long‐life wearable AZIBs.

Compared with ordinary graphite anode, SnO2 possesses higher theoretical specific capacity, rich raw materials and low price. While the severe volume expansion of SnO2 during lithium-ion extraction/intercalation limits its further application. To solve this problem, in this work the reduced graphene oxide (rGO) was introduced as volume buffer matrix of SnO2. Herein, SnO2/rGO composite is obtained through one-step hydrothermal method. Three-dimensional structure of rGO could effectively hinder the polymerization of SnO2 nanoparticles and provide more lithium storage sites attributed to high specific surface area and density defects. The initial discharge capacity of the composite cathode is 959 mA·h·g-1 and the capacity remained at 300 mA·h·g-1 after 1000 cycles at 1 C. It proved that the rGO added in the anode has a capacity contribution to the lithium-ion battery. It changes the capacity contribution mechanism from diffusion process dominance to surface driven capacitive contribution. Due to the addition of rGO, the anode material gains stable structure and great conductivity.