Nanopore battery

A nanopore battery is a rechargeable power source made up of billions of tiny battery units embedded in the pores of a supporting material. The holes are extremely small; the combined volume of billions of these pores is about the size of a single grain of sand, and each pore has a diameter roughly one eighty-thousandth the width of a human hair.

In a 2014 demonstration, the device was built from a ceramic sheet of anodic aluminum. It contained two electrodes made of vanadium pentoxide nanotubes, separated by an electrolyte that conducted the electrical charge between them. The current collector was made of ruthenium.

All the individual nanobatteries were connected in parallel. One end of the device was prelithiated to form the anode, while the other end used pure material to form the cathode. The battery operated asymmetrically, cycling between 0.2 V and 1.8 V.

The full cell retained 95% of its capacity at a 5 C discharge rate and 46% at 150 C, relative to its 1 C capacity, and lasted for 1,000 charge-discharge cycles. The demonstration unit could be fully charged in 12 minutes and was recharged thousands of times.

This system operates in an electrochemical regime where ion insertion and surface charge storage mechanisms become indistinguishable. It can also be used to study the limits of ion transport in dense, nanostructured electrode arrays.