Advances in Dye-Sensitized Solar Cell–Integrated Energy Storage Systems: Materials, Architectures, and Applications

Abstract: Dye-sensitized solar cells (DSSCs) have emerged as promising photovoltaic devices due to their low-cost fabrication, design flexibility, and strong performance under indoor and diffuse light. Recent advancements have expanded their role from stand-alone energy harvesters to integrated photovoltaic–storage systems, combining DSSCs with supercapacitors or rechargeable batteries for compact, self-powered solutions. However, challenges persist, including material degradation under light and thermal stress, electrolyte leakage, and performance mismatches between harvesting and storage units. Research efforts have focused on durable sensitizers, thermally stable redox mediators, and robust encapsulation methods to enhance stability. Innovative approaches such as perovskite-sensitized hybrid DSSC–storage devices, plasmonic nanostructures for improved light harvesting, bio-inspired and eco-friendly materials, and flexible/wearable formats address efficiency, durability, and sustainability concerns. Electrolyte engineering with ionic liquids, polymer gels, and quasi-solid systems has reduced volatility without significantly compromising conductivity. Future directions emphasize next-generation copper- and cobalt-based redox shuttles, solid-state integration for monolithic photo-rechargeable devices, and recycling-oriented “design for disassembly.” Commercial potential is strongest in indoor and building-integrated applications, where DSSCs outperform silicon in low-light conditions while offering aesthetic customization. Overcoming stability, scalability, and recycling challenges will be key to transitioning from laboratory prototypes to market-ready, long-lasting devices for Internet of Things (IoT), wearables, and smart infrastructure.