Optical And Thermal Performance Of Solar Cells Based On Structured PDMS Films

Solar energy is a kind of inexhaustible clean energy.Photovoltaic technology is an important means to solve energy crisis and alleviate environmental problems.Silicon-based solar cell had occupied more than 90%market share due to their stable efficiency,mature process and low cost,but the large optical loss of their surface and the high operating temperature limits the further improvement of photoelectric conversion efficiency.Therefore,it is of great significance to develop antireflection technology and cooling technology to reduce cost and increase efficiency of silicon-based solar cells.In this paper,micro-nano structured polydimethylsiloxane(PDMS)film prepared by template method was applied to the upper surface of crystalline silicon solar cells.The film can not only reduce the light reflection of the cell,but also discrease the operating temperature of the cell through passive radiation cooling,so as to improve the photoelectric conversion efficiency of solar cells.Firstly,the effects of pyramid structured PDMS films on the optical properties of planar silicon and pyramid textured silicon solar cells were studied by UV-Vis spectrum test and solar cell I-V curve test.The results showed that the photovoltaic conversion efficiency of planar silicon solar cells increased from 4.71%to 9.11%,and that of crystalline silicon solar cell with pyramid texture increased from 14.32%to 15.72%.Secondly,the passive radiation cooling effects of pyramid structured PDMS films on crystalline silicon solar cells was studied by outdoor cooling experiment and Fourier infrared spectrometer test.Compared with the planar PDMS film,pyramid structured PDMS film has higher thermal infrared emissivity and better cooling effect on crystalline silicon solar cells.The experimental results showed that the pyramid structured PDMS film can reduce the average temperature of the planar silicon solar cell by 7.41°C and that of the crystalline silicon solar cell with pyramid texture by 6.08°C.Finally,COMSOL Multiphysics software was used to simulate the effects of PDMS film with pyramid array micro-nano structure on the optical,radiation cooling power and electrical properties of planar silicon solar cells and silicon solar cells with pyramid texture surface.The simulation results showed that pyramid micro-nano array PDMS film can increase the photovoltaic conversion efficiency of planar crystalline silicon solar cell by8.87%and that of pyramid texturized silicon solar cell by 3.84%,respectively.And the radiant cooling power of planar crystalline silicon solar cell can be improved by 197.87W/m~2 and that of pyramid texturized silicon solar cell can be improved by 242.05 W/m~2 by pyramid micro-nano array PDMS film,respectively.