Conventional lithium-ion batteries are pretty useful, but they have their limitations. For one thing, because of the way their components are housed in metal canisters, they can only be manufactured as cylinders or rectangles. Pulickel Ajayan, Neelam Singh and their Rice University Colleagues have solved this problem by developing paintable batteries.
(a)Simplified view of a conventional Li-ion battery, a multilayer device assembled by tightly wound ‘jellyroll’ sandwich of anode-separator-cathode layers.
(b) Direct fabrication of Li-ion battery on the surface of interest by sequentially spraying component paints stencil masks tailored to desired geometry and surface.
Each component is spray-painted onto a surface in layers, as shown above. The researchers were able to use this technique to apply batteries to a number of materials, including glass, stainless steel and flexible polymer sheets. They even fabricated a battery directly onto the curved surface of a ceramic mug.