Analysis and Optimization of Sb2Te3 and Bi2Te3 Materials for Enhancing the Performance of Thermoelectric Energy Harvester for WSN Applications

Background: Thermoelectric (TE) materials are used to fabricate the thermoelectric generator (TEG). Thermoelectric Generator (TEG) is used to convert thermal energy into electrical energy and vice-versa. Bismuth-Telluride and Antimony Telluride (Bi/Sb)2Te3 alloys are popular in the research community due to its capability of electrical energy generation in the range of room temperature. The Phase Change Material (PCM) is a good source of thermal energy storage in thermal energy harvesting. We have reviewed patents having the information of thermal energy storage and tried to provide a better cost-effective solution in thermal energy harvesting using Phase Change Material (PCM) and material used in thermoelectric generator. Finding the most appropriate TE alloy for a particular application is a challenge in the research community. Objective: The objective of this paper is to conduct a study and analysis of performance parameter of (Bi/Sb)-Te based TE alloy along with the effect of Phase Change Material (PCM) on energy generation. Methods: An investigation over a wide range of temperature is performed. A Bi2Te3 based Commercial- of-the-shelf (COTS) Thermoelectric Generator (TEG) has been experimentally tested in a controlled temperature environment for the analysis of its efficiency. Result: This is found that maximum efficiency of 2.12% is achieved at a temperature difference of 60°C. Conclusion: This investigation will be useful for the selection of material for thermal energy harvesting techniques and helps to provide an optimized framework for the research community to decide the (Bi1-xSbx)2Te3 mixed crystal alloy for their applications.