Bio-nanobattery

Nobody has yet worked out how to make a good nanobattery, so nanoscale devices are typically driven by power sources many times their own size.A key problem is how to assemble a battery on such a tiny scale and a number of research groups have been working on exploiting the way biological molecules self-assemble for this task.NASA says one promising avenue is exploiting the ability of the protein ferritin to carry either a positive or negative charge. Ferritin also self assembles relatively easily into a uniform nanolayer. So, the agency says, it is straightforward to create a layer of ferritin and then cover it with another layer of the opposite charge. The result is a capacitor just a few nanometres thick that can store charge between its layers - in other words a battery. Adding more layers of alternately charged ferritin increases the capacitance of this bio-nanobattery. NASA reckons its battery is not only stable and robust but can be produced easily and quickly too.