Recent advances in V2O5-based cathode materials for electrochemical energy storage

Vanadium pentoxide (V 2 O 5 ) is a promising and versatile cathode material for next-generation electrochemical energy-storage systems. This promise arises from its diverse polymorphic structures, abundant redox-active sites, and distinctive two-dimensional layered framework. However, its practical application remains limited by several intrinsic deficiencies. These include low electronic conductivity, sluggish solid-state ion diffusion, and structural and thermodynamic instability during deep charge–discharge cycling. This review systematically examines the polymorphic characteristics of V 2 O 5 , together with its charge-storage mechanisms and structural evolution under different electrochemical conditions. Recent advances in V 2 O 5 -based materials are then reviewed across various metal-ion battery systems. These systems include monovalent-ion batteries based on Li + , Na + , and K + , as well as multivalent-ion batteries based on aqueous Zn 2+ , Mg 2+ , Ca 2+ , and Al 3+ . The physicochemical mechanisms underlying major modification strategies are subsequently analyzed, including nanoscale morphology engineering, interlayer pre-intercalation, defect and doping chemistry, and composite design. Finally, based on an in-depth understanding of the energy-storage mechanisms, a perspective on V 2 O 5 -based materials is presented. This perspective emphasizes the need to integrate material optimization, advanced in situ characterization of reaction kinetics, and multiscale theoretical simulations. This review aims to provide theoretical guidance and cross-system design directions for developing high-performance and stable V 2 O 5 -based energy-storage materials.