Supercapacitor from an Old T-Shirt
An old T-shirt was dissolved in alkali to produce a gel, and it became the heart of an energy storage device. The second component was made from chitosan, a substance derived from shrimp shells. No metals: just recycled cotton and seafood.
The gel was soaked in ammonium salt, and its conductivity nearly doubled: from 17.1 to 37.8 millisiemens per centimeter.