HYDERABAD: Next time you are outside and running out of battery in your smartwatch, earbuds, or other devices, your sweat can come to your rescue as the researchers from Birla Institute of Technology & Science (BITS) Pilani, Hyderabad Campus designed wearable devices to generate energy from human sweat. Through these devices, lactate present in sweat is used to harvest energy in a fuel cell format.
The researchers — Jayapiriya US, a research Scholar and Sanket Goel, professor, department of Electrical and Electronics Engineering, designed two types of electronic devices — one using a modified band-aid with pencil electrodes generating power of 115 mW/m2 and another using nanomaterial coated carbon cloth electrode generating power of 1.3 W/m2.
“Two different biofuel cells have been fabricated with a patch type configuration to harvest power from lactate present in human sweat. In the first method, pencil strokes were made on a simple band-aid to create a biofuel cell. While lactate acts as an electrode, graphene acts as both anode and cathode,” Goel told TOI. He said that different types of enzymes are added to graphene so that they act as cathode or anode.
In the second method, researchers used carbon cloth-based electrodes to convert lactate in sweat into energy.
Goel said that the energy generated can either be directly used when it is generated or can be saved and used later by using a capacitor.
The ultimate aim of these prototypes is to power wearable electronic applications such as fitness trackers, headphones, smart glass, and sensors among others, the researchers said. “The minimum voltage required to startup a fitness watch is around 1.8 V for which an array of our patch-type fuel cell can be used to supply the required voltage,” Goel added. “Using glucose to harvest energy can be useful to power battery of the peacemaker, a battery-operated device that sends el impulses to the heart muscle to maintain a suitable heart rate andrhythm,” he added.
