Analysis of batteries or supercapacitor as energy storage device for a sound energy harvester system

This study focuses on the concept analysis of the suitability of batteries or a supercapacitor as an alternative storage device in low‐power electronic devices. Sound waves were utilized as a source of energy for charging the supercapacitor, and a piezoelectric Q220‐A4‐503YB device was used as the energy transducer. A respectable performance of the piezoelectric in terms of the output force and voltage was found at the operating frequency of 68 Hz with an input source of 96 dB sound intensity level. Based on our experiments, it was found that the supercapacitor is more efficient as a storage device for a low‐power source when compared to batteries because of the charging current. The charging time of the 0.22‐F supercapacitor used in either the Villard or Dickson mode is higher when compared to the others. The charging time of the supercapacitor with the voltage regulator of 0.5 and 1.0 W by the Villard multiplier was longer compared to the Dickson multiplier, which produced an output voltage of 9.817 and 9.647 V, respectively. From this study, it is proven that the delivery of the voltage stored in a supercapacitor with a higher capacitance would take a longer time in terms of process charging and discharging as compared to one with a lower capacitance. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.