The emerging technology of 3D printing has been investigated as a way to improve on all sorts of technologies from toothbrushes to rocket engines. Now a Harvard researcher is working on a way to utilize 3D printing to improve one of the most vital components in consumer technology — batteries. Materials scientist Jennifer Lewis has developed new “inks” that can be used to 3D print batteries and other electronic components with current technology.
3D printing is already at work in the field of consumer electronics with casings and some smaller components being made on industrial 3D printers. However, the need for traditionally produced circuit boards and batteries limits the usefulness of 3D printing. If the work being done by Lewis proves fruitful, it could make fabrication of a finished product considerably faster and easier.
The Harvard team is calling the material “ink,” but is actually a suspension of nanoparticles in a dense liquid medium like ethylene glycol. In the case of the battery printing ink, the team starts with a vial of deionized water and ethylene glycol and adds nanoparticles of lithium titanium oxide. The mixture is homogenized then centrifuged to separate out any larger particles, which results in the ink used to print batteries.
Battery Printing
This process is possible because of the unique properties of the nanoparticle suspension. It is mostly solid as it sits in the printer ready to be applied, then begins to flow like liquid when pressure on it is increased. Once it has left the custom syringe applicator, it returns to a solid state. Lewis’ team has been able to lay down multiple layers of this ink with extreme precision at 100-nanometer accuracy. The tiny batteries being printed are about 1mm square, and could pack even higher energy density than conventional cells thanks to the intricate constructions.
This approach is much more realistic than other metal printing technologies because it doesn’t rely on the high temperatures. This all happens at room temperature and works with existing industrial 3D printers that were built to work with plastics. The team hopes that future work will make this type of nanoparticle extrusion possible on consumer-level 3D printers like the MakerBot.
Batteries
Batteries made from lithium inks are only one of the possible applications. The Harvard team has also experimented with silver nanoparticles to lay out wires and connections on a circuit board. It may be possible to construct entire devices — battery, electronics, and casing — with 3D printing technology that don’t have to be assembled by man or machine. You just input a design, and the finished product comes out ready to use.
http://www.extremetech.com/extreme/1...rint-batteries