Ca²⁺ and PVP Modified VO₂ Electrode Materials for High-Capacity and Temperature-Adaptative Zn-Ion Batteries

Vanadium-based oxides stand out as electrode materials with substantial commercialization potential for aqueous zinc-ion batteries owing to their eco-friendliness and remarkable energy density. Nevertheless, poor capacity retention and electrical conductivity impede their further development in wearable devices. Herein, synthesize CaVO₂-polyvinylpyrrolidone nanobelts through a facile hydrothermal strategy. At a current density of 0.5 A/g, the assembled cells provide a discharge capacity of 334 mAh/g. Meanwhile, the button batteries also maintain a discharge capacity of 279 mAh/g at an environmental temperature of 0 ℃ (1.0 A/g). The flexible pouch devices further present outstanding mechanical stability under various folding states.