
According to a recent Interesting Engineering article, researchers at Nanyang Technological University (NTU) in Singapore have developed a revolutionary micrometer-thin battery designed for smart contact lenses. Unlike existing methods that use wires and toxic metals for power, this innovative battery can be charged using human tears. The NTU research team created the battery from biocompatible materials with a glucose-based coating. The coating reacts with sodium and chloride ions in the water inside the battery, generating electricity and effectively charging the battery as the wearer uses the lenses. The battery’s capacity is sufficient to power the device for most of the day. Even better, immersing the battery in a simulated tear solution or concentrated saline solution enhances its lifespan, extending its usage time.