Renewable polymer electrolytes: Toward sustainable wearable energy devices

Rapid growth in wearable health-monitoring systems is accelerating demand for flexible, safe, and environmentally responsible energy-storage components. Nevertheless, conventional liquid electrolytes pose leakage and flammability risks, so they are poorly suited to skin-contact, mechanically deformable devices. Fossil-derived polymer electrolytes can deliver robust performance, but are typically persistent, which complicates end-of-life management of polymer wastes. Despite rapid advanced materials development, the literature lacks a comprehensive design-to-performance pattern connecting the green polymers chemistry with ion-transport mechanisms and wearable-device requirements. Renewable polymer-based electrolytes offer a compelling portfolio for designing safer and more sustainable wearable energy devices with higher potential for biocompatibility and reduced environmental consequences This review addresses strategies for manufacturing and application of renewable polymer electrolytes, demonstrating how microstructure and bonding in such systems improve ionic conductivity, electrochemical stability, and mechanical robustness under deformation. We also summarize device-oriented performance of renewable polymers in flexible batteries, supercapacitors, and biosensing platforms, followed by outlining research portfolio for sophisticated wearable device demonstrations. In particular, hybrid electrolyte systems, greener synthesis and processing routes, and recyclability-by-design aspects of wearable energy systems are reviewed toward innovative sustainable developments.