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@article{191909,
        author = {Yadav Pragati Gopal and Yadav Mansi Rampal},
        title = {A Triple-Harvesting wearable wristband for wireless smartphone charging using solar, Triboelectric, and Thermoelectric Energy},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {8},
        pages = {8442-8446},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=191909},
        abstract = {Every day millions of people run out of phone battery while they are away from home for many hours: traveling long distances, working outdoors, hiking, or moving between places where plugging in is inconvenient or impossible. This paper proposes a flexible wristband that helps in such situations by harvesting free ambient energy from three natural sources: sunlight using flexible solar cells, arm movement using a triboelectric nanogenerator (TENG), and body warmth using a thermoelectric generator (TEG).
All harvested energy is stored in a thin flexible battery and delivered to any smartphone through an integrated Qi wireless charging coil. Calculations and preliminary experiments show that during normal outdoor walking the wristband can deliver several watts, providing 10–20% phone battery in 20–30 minutes using only natural sources.
This work aims to create awareness that the small amounts of energy produced by daily human motion and body heat, together with sunlight, can reduce dependence on coal- and gas-based electricity that contributes to climate change. It gives freedom to students, travelers, soldiers, villagers, and children who cannot always find a plug. In the future, body-worn devices such as health sensors and smart glasses will rely on exactly these harvesting technologies. This wristband demonstrates one practical and achievable solution.},
        keywords = {energy harvesting, triboelectric nanogenerator (TENG), thermoelectric generator (TEG), flexible solar cells, wireless charging, wearable wristband, self-powered device, sustainable energy, emergency charging, hybrid harvesting},
        month = {January},
        }