Optimization of a PDMS structure for energy harvesting under compressive forces

J Shi,S P Beeby,Z Cao,D Zhu

doi:10.1088/1742-6596/660/1/012041

J Shi, S P Beeby + Show 2 more

Open Access

https://doi.org/10.1088/1742-6596/660/1/012041

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Abstract

This paper reports the optimisation of a PDMS structure for energy harvesting applications. The PDMS structure was optimised using ANSYS simulation. The fabrication processes were also optimised for maximum PDMS ferroelectret energy harvesting performance. The optimised PDMS structure was fabricated using a 3D-printed plastic mould. The ANSYS simulation and experiment results demonstrated the variation in energy harvesting performance of the PDMS ferroelectret depending upon the different void geometry. The optimised operating frequency is determined by the geometry of the voids inside ferroelectrets and the Young's modulus of the PDMS. The peak voltage and energy generated per strike under a compressive load was obtained experimentally as a function of force applied and frequency. The experimental maximum peak output power of an optimised PDMS structure with an area of 2×2 cm2 was 0.46 μW across an optimum load resistance of 21 MΩ under a square wave force of 800 N and 17 Hz.

Highlights

Ferroelectrets are thin films of polymer foams which can store electric charges in its internal voids, presenting strong piezoelectric-like properties after electric charging [1]
The ANSYS simulation and experiment results demonstrated the variation in energy harvesting performance of the PDMS ferroelectret depending upon the different void geometry
In this work, the simulation, fabrication and testing of PDMS ferroelectrets with a variety of dimensions has been investigated

Summary

Introduction

Ferroelectrets are thin films of polymer foams which can store electric charges in its internal voids, presenting strong piezoelectric-like properties after electric charging [1]. Kinetic energy harvesting technology that gathers energy from human motion, such as running and walking or ambient vibration, such as machinery vibration, has received growing attention over the last decade. This technology enables wearable devices to be operated using the power that is harvested from human activities. Published under licence by IOP Publishing Ltd relatively high d33 that is comparable to PZT These properties make it possible for using ferroelectrets as the active material to harvest energy from human motion and power wearable electronic devices. We have develop a model that predicts the variation in performance of PDMS ferroelectret with different void geometries [7].This paper presents the optimization, fabrication and testing of an optimized PDMS ferroelectret material for energy harvesting applications

Operating principle

Fabrication process for PDMS ferreoelectret

Results and Discussion

21 MΩ load resistance

Conclusion