Research Information System
Journal of Energy Storage, vol.150, 2026 (SCI-Expanded, Scopus)
Supercapacitors (electrochemical double-layer capacitors (EDLCs), hybrids, and pseudocapacitive types) bridge the gap between conventional capacitors and batteries. They offer high power densities (kW kg−1 range), rapid charging, and cycle lives exceeding 106 cycles. The global market is growing rapidly; valued at ~3.0 billion USD in 2024, it is projected to reach ~14.7 billion USD by 2034 with a Compound Annual Growth Rate (CAGR) of ≈17.5%. To meet the demands of this expanding market, increasing energy density is a priority. While current EDLCs typically provide 5–10 Wh kg−1, hybrid systems exceed 20 Wh kg−1, and prototypes are now approaching 60 Wh kg−1, which significantly enhances electric vehicle (EV) applications. This review summarizes advances from 2020 to 2025 in electrode materials, including carbons, transition metal compounds, two-dimensional transition metal carbides and nitrides (MXenes), Metal-Organic Frameworks (MOFs), Covalent Organic Frameworks (COFs), and conducting polymers. It also analyzes electrolytes (aqueous, water-in-salt, organic, ionic liquid, and solid/quasi-solid) and device concepts such as asymmetric and micro-supercapacitors. The discussion emphasizes material–electrolyte synergies, sustainable electrode design, and scalable synthesis. Unlike previous reviews, this work critically evaluates materials based on industrial feasibility, cost, and environmental footprint, rather than just capacitance. Despite rapid progress, challenges remain in enhancing energy density and ensuring sustainable manufacturing. Future research must focus on safe electrolytes and hybrid integration to establish supercapacitors as reliable energy storage technologies.