Researchers at the Nanyang Technological University (NTU) in Singapore have developed a groundbreaking battery that can power smart contact lenses and be charged with tears, according to a university press release. Contact lenses have traditionally been used for vision correction, but with advancements in technology, companies have been working on creating smarter versions that can connect to devices like smartphones and display information directly to the wearer’s eyes. However, these applications require the lenses to have an internal battery. In the past, companies have used thin batteries with induction coils and metal wires, which pose risks to the user’s eyes. However, a research team led by Assistant Professor Lee Seok Woo from NTU’s School of Electrical and Electronic Engineering has now created a battery that doesn’t use any metals. This innovative micrometer-thin battery can be charged using tears, making it a safer and more convenient option for smart contact lenses.