A paper battery powered with blood?

Research first published in 2007 by the Rensselaer Polytechnic Institute claim they make batteries that can be powered by blood, sweat, tears or even urine! That’s not all: this tiny battery is essentially made of PAPER!! The paper is made with tiny nanotubes imprinted into it as part of the process. The end result is nanocomposite paper which can be powered on directly from your body, allowing pacemakers or possibly even artificial hearts to be powered indefinitely—well, as long as you eat!
The scientists claim that nanocomposite paper the size of a newspaper could power a car, though they haven’t been able to make that much at a time yet. The applications are almost endless, because the battery would literally be as light and thin as paper, leaving more room and less weight in vehicles or planes. It would also be extremely flexible, allowing it to be molded in different shapes or to move with the body. 
Researchers are hoping in the future to be able to print big sheets which can then be cut to whatever size or shape is needed. The battery would even function normally with holes punched in it. 
Also, because it is essentially made of paper, the battery is extremely environmentally friendly when compared to most batteries we use today.
The catch? Well, while the materials themselves are cheap, it is way too expensive to produce in the sheets described above, and until they find a way to lower the cost of production, it just isn’t viable. They are continuing to research ways to boost the efficiency of the batteries and investigating different manufacturing techniques.

We also talked about the possibility of a bio-battery back in February here: http://ecomerge.blogspot.com/2013/02/the-bio-battery-its-alive.html