Geometrical optimization for high efficiency carbon perovskite modules

The carbon based perovskite solar cell (C-PSC) has a strong commercial potential due its low manufacturing cost and its improved stability. A C-PSC consists of three mesoporous layers sandwiched between a Fluorine-doped tin oxide (FTO) substrate as bottom electrode and carbon as top electrode. However, the low conductivity of the two electrodes represents a real challenge when scaling from individual cells to modules. Here, 2D direct current simulation is used to investigate the influence of width of the active area on the performance of a single C-PSC. The same method is used to study the effect of the sub-cell’s width, the interconnection’s width and the contact resistance at the interconnection on the performance of a 10 sub-cells module connected in series. The intrinsic properties of the carbon cell are taken in account using experimental JSC and VOC as an input to the modelling. The carbon conductivity is found to be critical in defining the optimum geometry. For a 10 Ω/sq carbon sheet resistance, the optimum interconnection width is 500 μm and the sub cell width is 4.9 mm, leading to an optimum fill factor of 64%.