Using flexible materials could generate power from the motion of the human body, extending battery life (for applications like pacemakers) or eliminating the battery altogether.

Princeton University researchers have developed a way to flex a usually inflexible piezoelectric (voltage-generating) crystal material, lead-zirconate-titanate (PZT), by making it into strips that could be attached to conducting silicone rubber to produce a flexible sheet that converts motion to electricity.

University of California at Berkeley researchers have created fibers from a piezoelectric polymer called PVDF with similar properties.