One of the biggest challenges for health tracking devices is battery life. Even if a product offers fantastic health and sleep information, the inevitable loading time will always leave users with a gap in their data, which can skew data trends, lead to inaccurate diagnoses, or fail to predict emergencies. As smart healthcare technology moves from post-detection to predictive models, the need for comprehensive monitoring data becomes more crucial than ever.
A new idea could solve any problems related to missing data in health trackers: charging via body heat. Researchers at Texas A&M University found a way to power a small electronic fever detector with body heat without requiring a large amount of heat, a backup battery, or a large chassis to house the sensor.
While the Texas A&M University Department of Mechanical Engineering project aims to improve public health by rapidly scanning large crowds for fever, the possible applications of the technology go far beyond a simple fever detector, as it could even function as an energy harvesting device. Additionally, battery technology could reduce costs compared to existing health monitoring sensors.
The concept is not new: there were the Matrix PowerWatch charged with body heat back in 2017—But this new project offers significantly longer battery life with a much smaller footprint than traditional health tracking solutions. Standard smartwatch displays and touchscreens require an enormous amount of power, and that would require much more heat than the human body can easily withstand to operate, and so the PowerWatch had to make significant compromises in usability in order to be charged by body heat, resulting in a dark screen and lack of touch functionality.
The Texas A&M University project takes advantage of steel electrodes to harness the thermal energy dissipated by a user. Given the typical corrosion rate of carbon steel, such a battery could last more than a decade.
Of course, a decade is not “indestructible.” And the project is still focused on a very small, single-purpose tracker, not multi-use or consumer-facing devices like smart rings and fitness bands. But it’s still a step in the right direction and an indication of where wearable technology can go in the future. After all, a health tracker that can’t be deleted could certainly be more useful than our current life-limited models.
