Carbon Nanotubes Turn Office Paper into Batteries

Plain white office paper could be the basis for efficient batteries. Scientists have converted sheets of them into efficient electrical storage devices using ink loaded with carbon nanotubes. This new spin on an ancient invention is the latest in a line of research striving to incorporate paper into batteries to reduce their weight, one of battery technology's major shortcomings.

To trim weight, researchers have tried several approaches, including the use of thin films of materials laid down as inks. The appeal of paper for centuries—its porous microscopic structure, which makes it ideal for holding onto inks—now intrigues researchers for modern applications, not to mention that paper is also a flexible, lightweight, affordable, well-established technology that is used everywhere and could be made from renewable sources.

To devise the novel paper batteries, materials scientist Yi Cui of Stanford University and his colleagues coated plain copy paper with black ink made with single-walled carbon nanotubes, which are electrically conductive pipes only billionths of a meter wide. Positive and negative electrodes—cathodes and anodes—were then applied as slurries dried on the nanotube-impregnated paper. (The cathodes were made from lithium manganese oxide nanorods, and the anodes made either from nanopowders of lithium titanium oxide or nanowires with cores of carbon covered with shells of silicon.) Click Here to Read the Full Article