Hybrid thermoelectric–battery architectures for self-powered wearable electronics

Wearable electronics demand a continuous and reliable power supply to support real-time monitoring and wireless data transmission. Conventional batteries, such as lithium-ion batteries (LIBs), provide high and stable energy densities but suffer from limited flexibility, safety risks, finite lifespans, and the need for frequent recharging, restricting their suitability for next-generation wearable platforms. Thermoelectric generators (TEGs) have emerged as promising alternatives, capable of continuously harvesting energy from body heat to enable self-powered operation. The inherently low and unstable power output of TEGs limits their ability to operate independently, especially in multifunctional devices. Recent hybrid approaches that integrate wearable TEGs with thin, safe, and rechargeable batteries have demonstrated significant potential by buffering intermittent TEG output and storing excess energy. Advances in material engineering, device architecture, and system-level integration have greatly improved the feasibility of these self-powered solutions. This review provides a comprehensive overview of TEGs and rechargeable batteries for wearable applications, with a focus on recent developments in TEG–battery hybrid systems, and discusses key challenges and future prospects toward fully self-sustaining wearable platforms. • Recent advances in wearable thermoelectric generators and flexible batteries are summarized • Hybrid TEG–battery architecture is a promising platform for wearable electronics • Innovations of energy materials and design enhance feasibility of self-powered wearables. • Future directions toward fully autonomous self-powered wearable devices are discussed