One of the biggest challenges for health-tracking devices is battery life. Even if a product delivers fantastic health and sleep insights, the inevitable charge 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 health tech moves from post-detection to prediction models, the need for complete tracking data becomes more crucial than ever.
A new idea just might solve any problems related to data gaps in health trackers: charging through body heat. Texas A&M University researchers found a way to power a small electronic fever detector with body heat without requiring a massive amount of heat, a backup battery, or a large chassis to house the sensor.
While the project from Texas A&M University’s Department of Mechanical Engineering aims to improve public health by rapidly scanning large crowds for fevers, the potential applications of the technology go well beyond a simple fever detector, as it could even function as an energy harvesting device. Additionally, the battery technology could lower costs compared to existing health monitoring sensors.
The concept isn’t new—there was the Matrix PowerWatch charged by 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 a massive amount of power, and that would require much more heat than the human body can easily put off in order to run, and thus PowerWatch had to make significant compromises to usability in order to be charged by body heat, resulting in a dim display and lack of touch functionality.
Texas A&M University’s project leverages steel electrodes to harness the thermal energy a user dissipates. Given the typical corrosion rate of carbon steel, such a battery could last for more than a decade.
Granted, a decade isn’t “unkillable.” And the project is still focused on a very small, single-purpose tracker, not on multiuse 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, an unkillable health tracker could certainly be more useful than our current, limited-life models.
