This study presents a novel hydrogel-based electronic skin (e-skin) capable of dual-mode sensing of temperature and strain. The e-skin leverages the thermocouple ion iodine/triiodide (I⁻/I₃⁻) redox couple, which is commonly used in disinfectants, to generate electricity through thermoelectric conversion. The hydrogel, synthesized from polyvinyl alcohol (PVA) monomers using a freeze-thaw method, exhibits flexibility, stretchability, and adaptability to human tissue. The addition of betaine enhances the hydrogel's resistance to dehydration and low temperatures, maintaining over 90% of its weight after 48 hours in the air. The hydrogel's thermogalvanic and piezoresistive effects enable self-powered sensing of temperature and strain, respectively. The e-skin was successfully integrated onto various body parts, including the cheeks, fingers, and elbows, demonstrating its potential in health monitoring and motion supervision. The device can detect head-down states and monitor foot movements, offering new possibilities for wearable intelligent electronics and robotics.This study presents a novel hydrogel-based electronic skin (e-skin) capable of dual-mode sensing of temperature and strain. The e-skin leverages the thermocouple ion iodine/triiodide (I⁻/I₃⁻) redox couple, which is commonly used in disinfectants, to generate electricity through thermoelectric conversion. The hydrogel, synthesized from polyvinyl alcohol (PVA) monomers using a freeze-thaw method, exhibits flexibility, stretchability, and adaptability to human tissue. The addition of betaine enhances the hydrogel's resistance to dehydration and low temperatures, maintaining over 90% of its weight after 48 hours in the air. The hydrogel's thermogalvanic and piezoresistive effects enable self-powered sensing of temperature and strain, respectively. The e-skin was successfully integrated onto various body parts, including the cheeks, fingers, and elbows, demonstrating its potential in health monitoring and motion supervision. The device can detect head-down states and monitor foot movements, offering new possibilities for wearable intelligent electronics and robotics.