One of the downside with current smart wearables is that most need to be recharged quite often, every day, week or month, and we’re still a long way of 10 year battery life offered by typical watches. I’m hopefully that eventually many devices won’t need to be recharged at all as we’ll have made improvements both in terms of power efficiency and energy harvesting using solar, body heat, vibrations and other techniques.
The prototype is using a modified baby diaper with a 320x5mm activated carbon piece, and a 1.8mm aluminum electrode placed between the absorbent and a waterproof sheet. The amount of electricity generated increases with the amount of urine, with the current peaking at the time of “release” as shown in the chart below.
All that electricity is stored in a capacitor, and when the amount of urine reaches a threshold level (80 cm3), the system transmits an ID signal over a wireless connection up to 5 meters. The system may be commercialized later for example to care of patients suffering from incontinence. The research paper about urine energy harvesting and self-powered diaper can be found on IEEE website.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.