Experimental study on fatigue degradation of piezoelectric energy harvesters under equivalent traffic load conditions

摘要

The fatigue life of piezoelectric energy harvesters (PEHs) under traffic load remains unclarified despite increasing research. Lead zirconate titanate (PZT) piezoelectric ceramics are widely used in PEHs, owing to their excellent piezoelectric properties. In this study, we fabricated a PZT-5H piezoelectric transducer, showing excellent performance, loaded it 10 million times under equivalent traffic loads, and investigated its ultimate fatigue life under intermittent and persistent loading. The micromechanism of fatigue depolarization and effects of different excitation loads and frequencies on the fatigue life of PZT-5H were studied. The degradation rate was 32.37% after 10 million intermittent loads (equivalent to 3 years of road traffic load), but reached 96.6% after 81 h of persistent loading. The fatigue degradation rate increased with increasing excitation loads and frequencies. Thus, PZT-5H piezoelectric transducers can replace disposable batteries for longer service life, if watt level output power is obtained.