A research team in Singapore has developed a teardrop-chargeable battery that can power smart contact lenses.
How Does The Battery Work?
The battery is made of biocompatible materials and has a glucose-based coating.
This coating can act as a circuit to generate electricity by reacting with the sodium and chloride ions present in the water inside the battery.
Since sodium and chloride ions are also present in tears, the lenses can practically charge while the wearer wears them.
Experiments revealed that the battery is capable of producing 45 microamperes of current and 201 microwatts of maximum power. This amount of power will be enough to run the device for most of the day. Tear charging also helps at this point.
When kept in simulated tear solution, battery life can be extended by an additional hour for every 12 hours of use. When not in use, the battery can be kept in a concentrated saline solution containing high amounts of glucose, potassium and sodium ions for charging.
The Team Found That The Battery Could Go Through 200 Charge-Discharge Cycles.
Li Zongkang, PhD student at NTU who took part in the study, said, “While wireless power transfer and supercapacitors provide high power, their integration poses a significant challenge due to the limited space in the lenses. By combining the battery and biofuel cell in one component, wired or wireless components “The battery can recharge itself without the need for additional space. Also, the electrodes placed on the outside of the contact lens ensure that the vision of the eye is not obstructed.” used the phrases.
The research was published in the journal Nano Energy.