A hyper-stretchable and deformable elastic-composite generator is developed using a piezoelectric nanocomposite composed of (1-x){Pb(Mg1/3Nb2/3)O-3}-(x){PbTiO3} microparticles, carbon nanotubes, a silicone rubber matrix, and very long silver (Ag) nanowire percolation network electrodes. To date, this nanogenerator sets world records for output performance, strain capacity, mechanical stability, and commercial feasibility in the research field for stretchable and deformable piezoelectric energy harvesters.