Batteries Are Now Unbelievably Tiny

Add this to the growing list of awesome stuff 3D printers make: a group from Harvard and the University of Illinois at Champaign-Urbana figured out how to print tiny batteries, no bigger than a grain of sand.

From Discovery News:

“To create the microbatteries, researchers used a custom-built 3-D printer to stack electrodes — each one less than the width of a human hair — along the teeth of two tiny gold combs. The electrodes were contained within a special ink, extruded from the printer’s narrow nozzles and applied to the combs like toothpaste being squeezed onto a toothbrush. The electrode inks, one serving as a cathode, the other as an anode, hardened immediately into narrow layers, one atop the other. Once the electrodes were stacked, researchers packaged them inside tiny containers and added an electrolyte solution to complete the battery pack. This novel process created a battery that could one day help power tiny medical implants as well as more novel electronics, like flying, insect-like robots. Such devices have been in development for some time, patiently awaiting an appropriately sized power source.”

Pretty great stuff, although if those insect-like robots are modeled after mosquitoes, we are happy to keep waiting patiently for their arrival, thank you very much. (Their real-life counterparts are irritating enough.)

These microbatteries join a long line of recent power-storage revolutions that have happened in just the past few years. None of these have made it to commercial-scale use yet, but it’s likely just a matter of time.

• In 2011 researchers at Stanford announced they had developed a transparent and flexible battery, which they hoped would give rise to transparent and flexible electronics like phones.
• Last summer, researchers at Rice University announced that they’d developed a spray-paint battery, able to be applied to household items, turning everyday objects into the next wave of power-carrying devices.
• This year, that same Rice lab published a paper about using graphene nanoribbons (a single atom thick) to improve battery life.
• Also last summer, engineers at the University of South Carolina figured out how to turn an ordinary t-shirt into a battery, hoping that one day it would be able to recharge electronics like phones and tablets.
• Scientists at Oak Ridge are using water as a greener alternative to the solvents traditionally used in lithium ion batteries.
• And the University of Maryland is also going green, using wood and tin to create batteries.

More from Smithsonian.com:

This Stretchable Battery Could Power the Next Generation of Wearable Gadgets

Mary Beth Griggs | | READ MORE

Mary Beth Griggs is a freelance science journalist based in New York City.