Electronic devices typically need to be manufactured with existing rectangular or cylindrical batteries in mind, but what products could be designed if it did not necessarily need to be in this shape?
Scientists recently created a proof of concept of soon to be 3D printed batteries, which can pave the way for practical batteries that could be made in any shape. Working alongside colleagues from Texas State University, a team led by Duke University's Benjamin Wiley and Christopher Reyes made the lithium-ion batteries out of poly (lactic acid) (PLA), using an inexpensive 3D printer.
Ordinarily, PLA would not work for such a purpose, as it is not an ionic conductor. However, to solve this problem, the scientists boosted the polymer's conductivity by infusing it with an electrolyte solution consisting of ethyl methyl carbonate, propylene carbonate and lithium perchlorate. Additionally – in order to further increase conductivity – they utilised graphene in the battery's anode, and carbon nanotubes in its cathode, as opposed to more traditional materials such as graphite.
The team successfully 3D-printed a functioning coin cell battery, along with an integrated battery within a LED-equipped bracelet, the latter of which was able to keep the LED illuminated for about 60 seconds. Although this form of 3D printing still has a far to go, the scientists could include the use of purpose-made 3D-printable pastes, instead of the enhanced PLA.
A paper on the research was recently published in the journal ACS Applied Energy Materials.