Revolutionary Battery Powered by Tears Could Fuel Smart Contact Lenses
A team of researchers in Singapore has made a groundbreaking discovery: a micrometer-thin battery that can store energy from human tears to power smart contact lenses.
Smart contact lenses have the potential to revolutionize the way we interact with technology. With the ability to provide turn-based directions, display notifications, and present other easily accessible data, these lenses eliminate the need for bulky smart glasses or external devices.
However, finding a suitable power source for these tiny contact lenses has been a major challenge. While display technology has significantly shrunk in size, batteries have not kept pace, often requiring impractical wires connected to external power sources.
Lead author Lee Seok Woo, an associate professor at Nanyang Technological University (NTU) in Singapore, explained the team’s inspiration for the research: “This research began with a simple question: could contact lens batteries be recharged with our tears?” In their new paper published in Nano Energy, the researchers detailed their findings.
A Safe and Sustainable Solution
The newly developed battery relies on glucose and water to generate electricity, making it safe for human use 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 produce electricity and power a circuit.
In a simulated eye experiment, the battery generated a current of 45 microamperes at a maximum output of 201 microwatts, which is sufficient to power a smart contact lens.
This innovative solution eliminates the need for bulky wireless charging. Coauthor Li Zongkang, a PhD student at NTU, 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 charge and discharge only 200 times, the research team is already collaborating with contact lens companies to bring this revolutionary technology to market.
Read more about smart contact lenses: Startup Shows Off Working AR Contact Lens You Can Actually Wear