Study On Performance Of Perovskite Solar Cells Under Low Irradiation Conditions

With the increased demand for energy,the fossil energy has been unable to meet human needs,and the search for and the use of renewable energy is becoming a global concern and research focus.Among all renewable energy sources,solar power is most likely to provide energy in the future.In recent years,perovskite solar cells have become a research hot spot because of their low cost,rich storage of raw materials,low energy consumption in production process,simple technology and high conversion efficiency.In this paper,with the support of device physics of perovskite solar cells,the core parameters are extracted by building circuit model and establishing parameter extraction algorithms.Based on this,the performance analysis of perovskite solar cells under low irradiation is discussed.(1)Based on the equivalent circuit model of perovskite solar cells,two parameter extraction algorithms are presented.In performance analysis,the core parameters of cells should be extracted first.The first algorithm considers J?V curves of open-circuit and short-circuit under different light intensities,chooses several measured values under different light intensities,and extracts corresponding parameters by linear fitting.Although the accuracy is high,the algorithm has requirements on the amount of data.In order to analyze the performance,a simpler and more accurate algorithm based on single J?V curve is proposed,that is,the maximum power point is introduced.The extraction parameters of #2 perovskite solar cells are validated.The results show that the algorithm is feasible and correct.(2)The performance variations of perovskite solar cells at low light intensity are investigated.At present,the demand for indoor optical devices is rising,and indoor irradiation is far below the standard conditions,so it is particularly important to study the performance under low irradiation.The solar irradiation dependent models main parameters including the short circuit current density,the open circuit voltage,the fill factor,and efficiency are confirmed.Then the variations of the main parameters with the intensity 0.01-1 kW/m~2 are discussed.It is shown that with the decrease of the solar intensity,the open circuit voltage shows an exponential decline.In the range of 0.37-1kW/m~2,the increase of the fill factor is mainly determined by the increase of the parallel resistance,while in the range of 0-0.14kW/m~2,the rise of the series resistance leads to the rapid decline of the fill factor.With the rise of the light intensity,the ideal factor goes up,and due to the obvious increase of the recombination effect inside the cells,the reverse saturated current density shows a grow trend.The trend of conversion efficiency is decided by both the fill factor and the open circuit voltage,and with the decline of solar light,it keeps almost unchanged firstly and then declines rapidly.In conclusion,the perovskite solar cell performs cell at the light intensity of 0.37kW/m~2 above.