Design And Optimization Of Solar Thermoelectric Battery System

With the continuous development of social economy,people have shown more and more demand for electric energy.For the sustainable development of the earth’s energy,green power generation methods such as solar energy,wind energy,and geothermal energy have become the choice of more industries.In 2020,the total amount of solar power generation surpassed wind power generation for the first time,becoming the first choice for green power generation.However,due to the existence of the ShockleyQueisser limit,most of the solar energy cannot be converted by solar cells,but becomes excess heat energy,and the working temperature of solar cells rises.In this situation,solar cells will have many problems,such as the drop in open circuit voltage,power generation,conversion efficiency,and shortened life.In response to this situation,this paper studies a power generation system that combines thermoelectric cells and solar cells.The excess heat generated by the solar cells is transferred to the thermoelectric cell through the system structure for thermoelectric power generation.Aiming at the problem of low power generation efficiency of thermoelectric batteries,this paper studies how to combine BN aerogel with thermoelectric batteries to improve its performance.Based on the above situation,this article mainly conducts three aspects of research:1)Optimized the design on the basis of the ordinary thermoelectric battery,using BN aerogel to increase the temperature difference between the hot and cold ends of the thermoelectric battery,and simulated the open circuit voltage of the three BN aerogel filling methods,and then based on the simulation The best model obtained was made in kind of thermoelectric battery;2)The solar cell and thermoelectric cell are combined to make a solar thermoelectric cell system.The solar cell test platform is designed and the system performance test is carried out.The results show that under the condition of an optical power density of100 m W/cm2,the comparison of solar cells in the system is The operating temperature of a single solar cell is reduced from 63.4°C to 32°C,and the photoelectric conversion efficiency is increased from 29.55% to 34.3%;3)Optimized the design of the unit power generation particles used in the thermoelectric battery module,compounded Bi2Te3 and BN aerogel,used ball milling technology to fully mix the two powders,and used hot pressing technology to make them into particles,and according to the quality Several sets of comparative experiments were carried out for different doping ratios.Finally,after a series of thermoelectric tests,the ZT value of the optimal set of composite thermoelectric materials reached 0.429.4)A simple PN junction thermoelectric cell was fabricated using composite thermoelectric materials and its performance was tested.The results showed that the open circuit voltage and power generation of thermoelectric cells made of composite materials increased by about 18.6% and 56.88%,respectively.