Supercapacitor could shrink size of mobile electronics

The power supply measures less than half a centimetre across and is made from a flexible material, opening up the possibility for wearable electronics. The research is published in the Royal Society of Chemistry journal Energy & Environmental Science.

Reducing the size of portable electronic devices requires power supplies to be shrunk along with an increase in the flexibility of power supplies in electronic circuits. Supercapacitors are attractive power supplies because they can store almost as much energy as a battery, with the advantage of high-speed energy discharge. Supercapacitor electrodes are normally made from carbon or conducting polymers, but these can be relatively costly.

A team led by Prof Oliver G Schmidt at the Leibniz Institute for Solid State and Materials Research in Dresden (IFW-Dresden) examined the use of manganese dioxide as an alternative electrode material, which is less expensive than the standard materials.

Manganese dioxide is not very electrically conductive, nor is it naturally flexible or strong. However, the scientists overcame this by vaporising the manganese dioxide using an electron beam and then allowing the gaseous atoms to precipitate into thin, bendy films. They incorporated very thin layers of gold into the films to improve the electrical conductivity of the material.