Optimizing front grid electrodes of flexible CIGS thin film solar cells with different shapes

Abstract

While using metal grid electrodes improves the performance of solar cells, it inevitably leads to frontal shading losses, series resistance losses, and losses due to lateral currents in the top layer. In this study, we analyze the influence of the front electrode grid line size parameters on the efficiency loss of copper indium gallium selenide (CIGS) thin-film solar cells and then use numerical analysis to obtain the optimal parameters for the design of the grid line size, and at the same time, explore the optimal design strategy for the grid line for non-conventional shaped solar cells. The experiments show that the photoelectric conversion efficiencies of the optimized rectangular solar cell samples are increased by 2.19% and 5.44%, respectively, over the two pre-optimized samples. The optimized design parameters can be used to improve the conversion efficiency of solar cell modules in commercial production, and the optimization method, which only modifies the relevant parameters of the grids, does not require the introduction of complex manufacturing methods in production, which can save costs and is easy to be extended to the production of different types of CIGS thin film solar cell modules in order to achieve the goal of improving efficiency.