Researchers Develop Micrometer-Thin Battery Powered by Tears for Smart Contact Lenses
A team of researchers in Singapore has made a breakthrough in the development of smart contact lenses by creating a micrometer-thin battery that can store energy from human tears. This battery could potentially power smart contact lenses, allowing users to receive turn-based directions, notifications, and other easily presentable data without the need for bulkier smart glasses or external devices.
The challenge of powering these tiny contact lenses has been a major obstacle. While display technology has become incredibly small, batteries have not kept pace, resulting in the need for impractical wires connecting to external power sources.
Lead author Lee Seok Woo, an associate professor at Nanyang Technological University (NTU) in Singapore, explained, “This research began with a simple question: could contact lens batteries be recharged with our tears?” In a new paper published in the journal Nano Energy, Woo and his team detail their findings and the potential of this innovative battery.
An Environmentally Friendly Solution
The micrometer-thin battery relies on glucose and water to generate electricity, making it safe for humans and less harmful to the environment when disposed of compared to conventional batteries. Constructed using biocompatible materials and featuring a glucose-based coating, the battery can react with sodium and chloride ions found in tears to generate electricity and power a circuit.
In an experiment using a simulated eye, the battery produced a current of 45 microamperes at a maximum output of 201 microwatts, which is sufficient to power a smart contact lens. This elegant solution could eliminate the need for bulky wireless charging.
Li Zongkang, a PhD student at NTU and coauthor of the study, explained, “By combining the battery and biofuel cell into a single component, the battery can charge itself without the need for additional space for wired or wireless components.”
While the technology is still in its early stages and has limitations, such as being able to be charged and discharged only 200 times, the research team is already collaborating with contact lens companies to bring this technology to market. The potential for smart contact lenses powered by tears could revolutionize wearable technology and provide users with a seamless and convenient experience.