SCIENTISTS DEVELOP ULTRA-THIN BATTERY FOR SMART CONTACT LENSES THAT COULD BE CHARGED BY TEARS

Summary from the TLDR newsletter

Researchers have created an ultra-thin battery about 0.2 millimeters thick. Powered by a biocompatible saline solution, the battery is thin enough to fit inside a 0.5-millimeter contact lens. The battery can use the glucose in tears to power up. Its capacity and voltage are currently very low and insufficient for powering data storage or an internet connection.