An 18-year-old recently won $50,000 in scholarship funds for inventing a supercapacitor that could one day be used to fully charge a mobile device like a smartphone in just a few seconds, TechSpot reports. Eesha Khare and two other teens were among the top winners at the annual Intel International Science and Engineering Fair. Her design, a tiny device that fits inside cell phone batteries, would allow them to fully charge within 20-30 seconds. The supercapacitor can last for up to 10,000 cycles which outpaces traditional batteries by a factor of 10…