Study of broad bandwidth vibrational energy harvesting system with optimum thickness of PET substrate

► A flexible PET-based vibrational energy harvesting system with broad bandwidth. ► The optimum thickness of substrate was determined by using an analytical formula. ► To analyze adhesion of multi-layer composite, nano-scratching test was used. ► The selectively deposited UV-curable resin lump structures as an additional mass. ► The relationship between the model solution and electric power was realized.