What Holds Nanoscale Batteries Back?
There are a number of potential uses for nanotechnologies, especially microelectromechanical systems, or MEMS. These are microscopic devises that use electrical energy to power mechanical changes, such as moving an arm or opening a container in the MEMS. That electrical energy has to come from somewhere though, and nanoscale batteries have been having some issues, but researchers at NIST, the University of Maryland, College Park, and Sandia National Laboratories have identified part of the problem.
At very small sizes, the potential for quantum mechanical effects increase. In a battery designed to be nanometers long, electrons do not always have to behave as they do in macroscale batteries. Using a transmission electron microscope, the researchers watched current move through multiple batteries built into nanowires and saw electrons were jumping across the electrolyte in some designs. If the electrolyte layer was less than 200 nm thick, the electrons could just tunnel through it, causing a short circuit, which drains the battery very quickly.
The tested batteries all used the same electrolyte, a lithium ion material, so it should be possible to achieve better results with a different electrolyte. Now that material just has to be found for MEMS to really take off.