Researchers 3D print custom-sized lithium-ion batteries

It has interesting implications for the future of small devices.

One of the challenges in creating smaller and smaller devices these days, such as wearables and phones, is that the batteries can take up a lot of room. Cases are often designed around standard battery sizes, and it often creates wasted space. Now, new research published in ACS Applied Energy Materials shows that it's possible to 3D-print lithium-ion batteries into whatever shape you need.

The problem that has stood in the way of 3D-printed lithium-ion batteries (at least, until now) is that the polymers traditionally used in this kind of printing aren't ionic conductors. The goal was to find a way to print custom-sized lithium-ion batteries in a cost-effective way using a regular, widely available 3D printer.

In order to make the batteries conductive, the team led by Christopher Reyes and Benjamin Wiley infused the polylactic acid (PLA) usually used in 3D printing with an electrolyte solution. The researchers also incorporated graphene and carbon nanotubes into the design of the case to help increase conductivity. After these design modifications, the team was able to 3D print an LED bracelet, complete with a custom-sized lithium-ion battery.