Thin film power supply carries superior energy density and could usher in next age of miniature electronics.
Scientists have created a powerful micro-supercapacitor that could help electronics companies develop mobile phones and cameras that are smaller, lighter and thinner. Less than half a centimetre across and only nanometres thick, the tiny power supply, the researchers say, can store more energy and provide more power per unit volume than state-of-the-art supercapacitors.
According to research published in the Royal Society of Chemistry journal Energy & Environmental Science, the micro-supercapacitor has a maximum energy density of 1.75 mW h cm−3 and a maximum power density of 3.44 W cm−3, both of which are higher than shown by solid-state supercapacitors..
To make the thin film, the team — led by Professor Oliver Schmidt at the Leibniz Institute for Solid State and Materials Research in Dresden — vaporised manganese dioxide using an electron beam and then allowed the gaseous atoms to precipitate into thin, bendy films. They then added thin layers of gold to improve the electrical conductivity.
“The major challenge we had to overcome in developing this technology was to obtain really high energy density on the micro-scale, at a low cost,” Dr Chenglin Yan, leader of the research group at IFW-Dresden. “The inclusion of gold in our micro-supercapacitor makes it more expensive, so we are now looking at replacing gold with cheaper metals, such as manganese, to make the device more practical for the market.”