New frontier of hybrid energy storage devices: evolution of capacitive mechanisms and escalation of nanocomposite materials

The growing popularity of portable electronic devices has led to a high demand for advanced energy storage technology, driven by advancements in power generation, electrification, and transportation. Hybrid energy storage devices offer high energy density, wide potential windows, rapid charging, long cycle life, and flexibility. Nanostructured materials further enhance device performance through synergistic effects. This review compiles a comprehensive range of materials, showcasing their evolution from traditional to advanced forms based on enhanced properties for hybrid energy storage devices. It also critically examines the mechanisms specific to material groups, informed by research advancements. Along with this, we critically describe the adjacent mechanisms that are possessed by individual groups of materials from the evolution phenomena of research progress. Future research scope has also been discussed with focus on the potential of new nanocomposite materials in enhancing capacitive mechanisms.