Researchers at Rice University in Texas have developed a battery which can be painted onto almost any surface. The team began by converting all the components of a lithium-ion battery into paints. It then layered the paints on top of each other, emulating the structure of a conventional cell. Once correctly layered, the paint was able to store and discharge energy like any battery. The team sprayed nine ceramic tiles with the paints and connected them in parallel. The resulting battery proved capable of delivering a steady 2.4 volt current over six hours and retained around 98 percent of its capacity after sixty charge cycles. At present each two-inch tile provides about 30 mAh (around 120 mAh per gram of lithium titanium oxide).
If it can be refined and perfected, the technique developed by the researchers could result in freedom from the traditional constraints of rectangular and cylindrical Li-ion batteries, allowing for more diversity in design. Lead researcher Neelam Singh says the process could also be combined with solar panels, or even solar paint, to create stand-alone energy capture and storage devices. Singh envisions both industrial-scale production and do-it-yourself spray cans being used in the future, but notes that the materials found in Li-ion batteries are both highly toxic and sensitive to moisture and oxygen, so another compound would have to be used to facilitate spraying your own batteries at home.