Researchers have created "microbatteries" with 3D printing.
A research team from the Wyss Institute at Harvard University and the University of Illinois at Urbana-Champaign have successfully printed lithium-ion microbatteries the size of a grain of sand. To make the microbatteries, researchers printed precisely interlaced stacks of tiny battery electrodes, each smaller than the width of a human hair.
Researchers used a custom-built 3D printer which extruded special inks through a minuscule nozzle. Red ink created the battery's anode, cathodes were purple, and a green case encapsulated the parts before an electrolyte solution was added to create a working microbattery.
In the past, engineers have used thin materials to build electrodes, but solid-state microbatteries do not pack sufficient energy to power today's miniaturized devices. Instead, the Harvard team designed the layers to be as narrow -- but contain nanoparticles of lithium metal oxide compounds based on the theory that parallel plane electrodes will exude more energy.
"The electrochemical performance is comparable to commercial batteries in terms of charge and discharge rate, cycle life and energy densities. We're just able to achieve this on a much smaller scale," commented Shen Dillon, co-author of the study alongside Jennifer Lewis.
The Harvard team says that the new batteries could be used in applications including medical implants and compact electronics. Beyond the medical field, the technology could be used to power insect-like robotics, tiny cameras and microphones.
The results are available in the journal Advanced Materials.
Image credit: Harvard