Here soon you will be able to choose which color you want your rechargeable batteries to come in. Red? Blue? Wired has the latest on a new innovation in batteries: spray on rechargeables!
Lithium-ion batteries are made by tightly rolling up the various battery components in layers before encasing them in rectangular or cylindrical packaging. The engineers, from Rice University in Texas, devised their own unique version of a multilayer battery by painting these individual battery components (two current collectors, a cathode, an anode and a polymer separator) on to select surfaces in layers. These layers included paints made from lithium cobalt oxide (a positive electrode), lithium titanium oxide (a negative electrode) and conductive single-walled nanotubes (a current collector). The special polymer paint blend helped achieve superior conductivity by forming the micro-porous layer required in a lithium battery.
The final paints were layered on to glass, stainless steel, glazed ceramic tiles and flexible polymer sheets — the resulting “batteries” worked just as well as the regular version. The team even picked out a choice ceramic mug, spray-painted the word “rice” in capital letters using a stencil, and demonstrated its efficiency as a battery.
Photo by Daniel Naish