Functionally graded piezoelectric composites for strain energy harvesting in car tyres

High-strain environment of automotive tyres provide deformation energy that can be harvested using piezoelectric materials for powering electronics such as Tyre Pressure Monitoring Systems (TPMS). This would reduce the reliance of the wireless sensor network on batteries. The resulting elimination of battery replacement will simplify maintenance and provide a higher level of ease of use and safety.

None of the present piezo-ceramic devices can easily operate under high strain conditions present in a car tyre, often leading to complex and costly solutions. The polymer based devices on the other hand fail to easily satisfy the operating thermal requirements for use in such an environment. However novel piezoelectric ceramic-polymer composite materials can be designed to fulfil the operating requirements by the right choice of the constituent phases as well as the microstructure. Furthermore, these materials are suitable for low-cost mass production and easy integration in the tyre itself.

This project aims to develop highly sensitive innovative composite materials to convert mechanical deformation into electrical energy via piezoelectric effect. The project will involve design of conformable composites based on piezoceramic-porous polymer systems with enhanced energy harvesting performance. The superior performance is due to a careful design of the microstructure, via including porosity as well as piezoceramic particle architectures. The choice of the constituent phases is another design parameter to be optimised in this project.

The Department of Mechanical Engineering of the University of Bath is looking for a highly motivated candidate to:

• Design and fabricate piezoelectric composite materials
• Characterise electro-thermo-mechanical properties using dielectric spectroscopy, impedance spectroscopy as well as direct piezoelectric measurement of charge and voltage output. Thermo-mechanical properties will be tested using TGA, DSC, DMTA. Microstructure of the composites will be analysed using SEM.
• Map the effect of porosity, and develop a model to predict the effective electromechanical properties of the porous composites
• Optimise the energy harvesting FOM based on properties of the constituent materials
• Characterize different electrode materials
• Mount the manufactured foil-type flexible piezo energy harvesters inside a car-tyre and evaluate the signal.
• Develop a self-powered system based on the existing TPMS devices


Candidates should send their application electronically containing an application letter, CV, diploma/degree/ transcripts, and reference letters to [Email Address Removed]. Essential Background: First class honours MSc degree (or overseas equivalent) in materials//chemical/mechanical/electrical engineering, physics or similar disciplines. Knowledge of MATLAB, LabVIEW and Signal Processing would be advantageous.