IIT Mandi researchers propose technique to enhance power output of piezoelectric materials

Indian Institute of Technology, Mandi researchers have proposed a technique to enhance the power output of piezoelectric materials which can be used in floor tiles to generate electrical energy from human walking or on roads, according to officials.

Piezoelectric materials produce an electric current when they are placed under mechanical stress.

According to the researchers' team, they numerically studied piezoelectric materials that interconvert mechanical energy and electrical energy and have proposed a new arrangement to enhance the electrical output of these materials when subjected to stress.

The results of the team work have been published in the journal Engineering Reports.

"Piezoelectric materials can generate electrical energy when a force is applied on them, and are thus extremely useful. Such materials can, for example, be used in floor tiles to generate electrical energy from human walking, or on roads, where the weight from the vehicles can power road lights and signals.

However, currently, the electrical energy produced by these materials is very low, which limits their applications in real life situations," said Rajeev Kumar, Associate Professor, IIT Mandi.

Rahul Vaish, also an associate professor at the institute said, "We have developed a technique known as 'graded poling' to enhance the power output of piezoelectric materials by over 100 times. The researchers have used numerical techniques to utilise multiple mechanical stresses - bending, compressive and tensile stresses at the top and bottom of the piezoelectric cantilever beams and shear stresses in the mid-section - in order to significantly improve the electrical output. The researchers have recommended possible steps to achieve these designs in practice, such as partially connecting the right face of the sample to ground and top faces being applied with an electric potential."

The promise of generation of higher amounts of electrical energy from mechanical movement can potentially enable applications in which smart devices can be powered simply by human motion, he added.

Other applications could include generating power from the soles of footwear equipped with these materials.

"Piezoelectric materials can do the reverse as well - generate mechanical motion in response to electrical energy. Thus improving the mechanical-electrical energy interconversion efficiency can enable engineering applications such as reduction of vibration and noise and advanced technological applications like positioning and steering of satellite antennas in space," Kumar said.

He said the researchers are extending their work further for more accurate prediction of the effects of the proposed poling technique on the mechanical properties of the material, which will offer better insights into harnessing the advantages of this technique in real life applications.

Other members of the team included research scholars Raj Kiran and Sourav Sharma, besides Anuruddh Kumar, IIT Mandi alumnus.