A new super-tiny battery made of wood, discovered by a team of scientists at the University of Maryland, seems to fulfill all the prerequisites of a cleaner, greener energy source that's long lasting and easy to handle.

Its teeny-tiny size, which is several thousand times thinner than a sheet of paper, makes it a clear example of how amazingly nanotechnology can work. What's more, this battery can store huge amounts of energy all at once, and is totally environment-friendly.

Rechargeable batteries, such as those in cellphones, use lithium to store energy. Sodium, on the other hand, which is used to store energy in this battery, doesn't store energy that efficiently; so your cellphone batteries won't be changing anytime soon. Instead, these batteries will be supposedly used for commercial purposes and where huge amounts of energy are required to be stored at once, such as in a solar energy power plant.

Coming to it composition, this battery is basically a tiny, thin sliver of wood, that is coated by a thin layer of tin. The wood fibers help keep this fragile battery in shape.

"The inspiration behind the idea comes from the trees," assistant professor of materials science, Liangbing Hu explained. "Wood fibers that make up a tree once held mineral-rich water, and so are ideal for storing liquid electrolytes, making them not only the base but an active part of the battery."

Also, this battery seems to be resistant and tough, and may survive several cycles of getting charged and re-charged. Computer models demonstrating the wrinkles formed on the wood battery, after several charging and discharging sessions, showed that these wrinkles relax the stress in the battery, making it fit for the long run, lead author Hongli Zhu, and her team members found.

"Pushing sodium ions through tin anodes often weaken the tin's connection to its base material," Li, an associate professor of mechanical engineering, explained. "But the wood fibers are soft enough to serve as a mechanical buffer, and thus can accommodate tin's changes. This is the key to our long-lasting sodium-ion batteries."

This research was supported by the University of Maryland and the US National Science Foundation.