Perovskite/c-Si tandem solar cells with realistic inverted architecture: Achieving high efficiency by optical optimization

Many theoretical analyses for perovskite/c-Si monolithic tandem solar cells (TSCs) have shown optical optimization and high efficiency limits, but they use many idealized assumptions and draw some unpractical conclusions for experiments. In this work, we have introduced a composite method combining the finite difference time domain and light path analysis for the first time. By using this method, we have systematically calculated perovskite/c-Si monolithic TSCs with inverted architecture based on realistic solar cell parameters. Theoretical results have demonstrated very good match of the experimental external quantum efficiencies of both subcells. More importantly, from optical and electrical point of view, we have analyzed current losses of such TSCs and proposed detailed optimization for achieving high efficiency. Finally, we have presented improved configuration of perovskite/c-Si monolithic TSCs with addition of pyramids structure in front surface, which can effectively increase the tandem cell efficiency to 29.05%. This work can be served as a practical guidance for the realization of high-efficient perovskite/c-Si monolithic TSCs.