Piezoelectric energy harvesting from ambient vibrations is well studied, but harvesting from quasi-static responses is not yet fully explored. The lack of attention is because quasi-static actions are much slower than the resonance frequency of piezoelectric oscillators to achieve optimal outputs; however, they can be a common mechanical energy resource: from large civil structure deformations to biomechanical motions. The recent advances in bio-micro-electro-mechanical systems and wireless sensor technologies are motivating the study of piezoelectric energy harvesting from quasi-static conditions for low-power budget devices. This article presents a new approach of using quasi-static deformations to generate electrical power through an axially compressed bilaterally constrained strip with an attached piezoelectric layer. A theoretical model was developed to predict the strain distribution of the strip’s buckled configuration for calculating the electrical energy generation. Results from an experimental investigation and finite element simulations are in good agreement with the theoretical study. Test results from a prototyped device showed that a peak output power of 1.33 μW/cm2was generated, which can adequately provide power supply for low-power budget devices. And a parametric study was also conducted to provide design guidance on selecting the dimensions of a device based on the external embedding structure.
Converting mechanical energy from either the ambient environment or the human body motions to the useful electrical energy will revolutionize power solutions for flexible electronics. Here, a hybrid energy harvesting strategy is reported, which combines porous polymeric piezoelectric film with an electrostatic layer as an integration for converting the mechanical energy into electrical energy. The piezoelectric materials through engineered microstructures are developed to enhance energy generation due to the higher compressibility and larger surface contact area. The electrostatic effect from the charged layer further contributes to the generation of electrical charges. By directly coating the stretchable carbon nanotubes onto the elastomers, more intimate integration of the hybrid energy harvesters enables the designs for complex electronics. Such flexible hybrid piezoelectric‐electrostatic device exhibits superior energy harvesting performance with a voltage output of 1.95 V, which improves 30% and 100% compared to the electrostatic and piezoelectric alone device, respectively. Experiments are also performed to demonstrate the implementation of the hybrid device's energy conversion to power small electronics and recognition of different body motions. Such hybrid strategy provides a new solution toward future energy revolution for flexible electronics.
more » « less- Award ID(s):
- 2106459
- PAR ID:
- 10394778
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 10
- Issue:
- 8
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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