How is this for the ultimate miniaturization of energy storage: A new tiny nanopore includes all the components of a battery though it is just is a tiny hole in a ceramic sheet that holds an electrolyte to carry the electrical charge between nanotube electrodes at either end - and 1,000,000,000 can fit in the size of a postage stamp. 

The existing device is a test but the nano-sized battery performs well - and it can be fully charged in 12 minutes, thousands of times.  

One of the reasons the researchers think this unit is so successful is because each nanopore is shaped just like the others, which allows them to pack the tiny thin batteries together efficiently. The space inside the holes is so small that the space they take up, all added together, would be no more than a grain of sand.

Each end of the tiny pore is treated to add nanotubes that collect the electrical charge conducted by the liquid electrolyte filling the pore. Credit: NEES

Now that the scientists have the battery working and have demonstrated the concept, they have also identified improvements that could make the next version 10 times more powerful.

The next step to commercialization: the inventors have conceived strategies for manufacturing the battery in large batches.

A billion nanopores could fit on a postage stamp. Credit: NEES, a DOE Energy Frontier Research Center