Researchers at Singapore’s Nanyang Technological University (NTU Singapore) have developed a thin and flexible paper battery that has significant potential as a component in wearable health technology. The device consists of cellulose paper reinforced with a hydrogel and external screen printing electrodes. It can provide strength when bending and even when cutting apart. After all, unlike most batteries, the technology is environmentally friendly and collapses completely within four weeks if buried in the ground.
The effective and sustainable power supply of portable health sensors is a hurdle for the medical technology industry. Batteries are usually not environmentally friendly and traditionally rigid and bulky – not ideal properties for a flexible, skin-tight wearable. Wearables are often designed as single-use items, and the resulting need to dispose of thousands of batteries when using and disposing of such devices adds to a huge environmental footprint.
“Traditional batteries come in a variety of models and sizes, and choosing the right type for your device can be a tedious process,” said Fan Hongjin, one of the developers of the new battery technology. “Through our study, we have shown a simpler, more cost-effective way to make batteries by developing a single large piece of battery that can be cut to the shapes and sizes desired without sacrificing efficiency. These properties make our paper batteries ideal for integration into the kind of flexible electronics that are gradually being developed. ”
The battery is made of cellulose paper that the researchers soaked with a hydrogel to strengthen it. They then screen-print the electrodes on both sides of the cellulose paper, with the anode ink consisting of zinc and a type of conductive carbon and the cathode containing either manganese or nickel. Finally, the researchers coat the electrodes with gold foil to increase their conductivity.
“We believe that the paper battery we developed could potentially solve the e-waste problem because our printed paper battery is non-toxic and doesn’t require an aluminum or plastic case to encapsulate the battery components,” said Lee Seok Woo, another researcher on the study. “The fact that there are no layers of packaging also enables our battery to store a higher amount of energy and thus more power in a smaller system.”
Check out a video about the battery below.
Studies in Advanced Science: Batteries made from printed zinc paper
Flashback: Washable and flexible batteries for portable medical devices
Over: NTU Singapore
