Cellular phone giant Nokia has filed for a patent for a self-regenerating phone battery, or in their own words, a "piezoelectric kinetic energy harvester". The patent essentially involves a battery that’s “contained within a first frame that is coupled to a second frame by one or more piezoelectric elements.”
Similar to the concept of kinetic powered watches, which use motion to charge their batteries, Nokia's technology proposes generating energy by kinetic movement. Nokia plans to use this energy “to at least partially recharge the device battery”.
Nokia envisions a phone in which its heavier components, say, the battery and radio transmitter circuits, travel along a pair of rails perpendicular to one another, and finally coming into contact with the capacitor, which charges the battery.