A Critical Review of High-Performance Microsupercapacitors for Next-Generation Wearable Electronics

Microsupercapacitors (MSCs) have emerged as promising microscale energy-storage technologies for next-generation wearable, flexible, stretchable, and miniaturized electronics owing to their high-power density, rapid charge-discharge capability, excellent rate performance, and long cycle life. However, simultaneously achieving high energy density, mechanical flexibility, device reliability, scalable fabrication, safety, and sustainability remains challenging. This review critically examines recent advances in high-performance MSCs, covering fundamental charge-storage mechanisms, electrode materials, electrolytes, electrode-electrolyte interfaces, microfabrication strategies, and device architectures. Particular emphasis is placed on carbon-based materials, MXenes, transition-metal compounds, conducting polymers, and hybrid heterostructures designed to enhance charge-storage kinetics and energy density. Recent progress in planar, three-dimensional, flexible, stretchable, deformable, kirigami-inspired, liquid-metal-based, and self-healing MSCs is discussed in relation to their electrochemical and mechanical performance. The integration of MSCs with wearable sensors, smart textiles, triboelectric nanogenerators, wireless charging systems, and other emerging electronic platforms is also highlighted. Furthermore, critical challenges associated with energy-power trade-offs, mechanical durability, temperature stability, manufacturing scalability, safety, reproducibility, and environmental sustainability are evaluated. Finally, future perspectives toward multifunctional, reliable, sustainable, and autonomously integrated MSCs are proposed, providing guidance for translating laboratory-scale advances into practical energy-storage technologies for next-generation wearable electronics.