Prof. Keon Jae Lee and co-workers had made a progressive breakthrough for enhancing the operating efficiency of self-powered flexible piezoelectric energy harvester. The flexible and lightweight energy harvester, called nanogenerators, can scavenge external force from the extremely tiny impulsion triggered by wind flow, water flow, heartbeats, diaphragm activities, and respiration movements so as to convert it into electrical signals, which not only constructed self-powered flexible electronic systems, but also was exploited as permanent power sources for implantable biomedical devices such as cardiac-tachometers, pacemakers, and deep brain stimulators. Until now, poor efficiency and complicated fabrication process are regarded as biggest barrier against mass commercialization. Transferring high-quality piezoelectric thin film from sapphire to plastic substrate via laser lift off (LLO) technique made the PZT thin film nanogenerator show high-output performance of ~250V which is enough for turning on 100 LEDs. This is almost 40 times higher than previously reported similar concepts.