Broad bandwidth vibration energy harvester based on thermally stable wavy fluorinated ethylene propylene electret films with negative charges. (4th April 2018)

• Record Type: Journal Article
• Authors: Zhang, Xiaoqing; Sessler, Gerhard M; Ma, Xingchen; Xue, Yuan; Wu, Liming
• Is Part Of: Journal of micromechanics and microengineering. Volume 28:Number 6(2018:Jun.)
• Publication Date: 2018-04-04
• Subjects: vibration energy harvester -- electret -- wavy FEP -- broad bandwidth; Microelectromechanical systems -- Periodicals; Micromechanics -- Periodicals; 621.38105
• DOI: 10.1088/1361-6439/aab57d
• Languages: English
• ISSNs: 0960-1317

Abstract

Abstract: Wavy fluorinated ethylene propylene (FEP) electret films with negative charges were prepared by a patterning method followed by a corona charging process. The thermal stability of these films was characterized by the surface potential decay with annealing time at elevated temperatures. The results show that thermally stable electret films can be made by corona charging followed by pre-aging treatment. Vibration energy harvesters having a very simple sandwich structure, consisting of a central wavy FEP electret film and two outside metal plates, were designed and their performance, including the resonance frequency, output power, half power bandwidth, and device stability, was investigated. These harvesters show a broad bandwidth as well as high output power. Their performance can be further improved by using a wavy-shaped counter electrode. For an energy harvester with an area of 4 cm 2 and a seismic mass of 80 g, the output power referred to 1 g ( g is the gravity of the earth), the resonance frequency, and the 3 dB bandwidth are 1.85 mW, 90 Hz, and 24 Hz, respectively. The output power is sufficient to power some electronic devices. Such devices may be embedded in shoe soles, carpets or seat cushions where the flexibility is required and large force is available.