Strategic Development of Electrode and Electrolyte Materials for High-Performance Supercapacitors

Supercapacitors, renowned for their high-power density, long cycle life, and rapid charge–discharge capabilities, are increasingly recognized as essential energy storage devices. This review presents a comprehensive analysis of advanced materials for both electrodes and electrolytes in supercapacitor systems. Emphasis is placed on carbon-based materials, metal oxides, conducting polymers, and novel hybrid structures, alongside the role of various electrolytes including aqueous, organic, and ionic liquids. Mechanistic insights, design strategies, and the synergistic integration of materials are discussed in light of improving energy and power densities. Current challenges and future research directions are also explored to guide the rational development of next-generation supercapacitors.