The hole story for miniature batteries

The technology behind a new generation of compact rechargeable batteries could be based on holes, according to researchers from the University of Maryland

A team led by Chanyuan Liu of the Maryland NanoCentre has developed a system which includes all the components of a battery in the form of a nanopore, a minute hole in a ceramic sheet filled with a liquid electrolyte and with a nanotube electrode at either end.

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The main material for the battery is aluminium oxide in a ceramic form, with the electrodes formed from an outer tube of ruthenium and an inner one of vanadium pentoxide; at one end, the vanadium pentoxide is treated with lithium to form an anode, while at the other end it is untreated and forms the cathode. Because the individual cells are so small and all the same shape, many millions can be packed together into a small space, the researchers explain in a paper in Nature Nanotechnology; Liu says that the system can be fully charged in 12 minutes and recharged thousands of times.

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The current version of the battery array is a proof of concept, the team says; it is now researching manufacturing methods and trying to improve the system to increase the amount of energy density tenfold.