Analysis of the effect of diffusion length distributions on global solar cell parameters by simplified 2D modelling

A simple analytical tool is introduced that allows to include the information given in spatially resolved measurements of one cell parameter (e.g. lifetime, shunt resistance, surface recombination velocity, ...) in 1D solar cell modelling. The model is applied to spatially resolved diffusion lengths: Different weighing functions for the quasi 1D model are discussed and compared, resulting in weighing functions which give excellent results of cell parameters for different cell technologies and diffusion length frequency distributions. Conventional 1D analysis, the new quasi 1D analysis method and 2D models, which fully account for diffusion length distributions are compared. The quasi 1D analysis is found to be in excellent agreement with the full model in all cell parameters, whereas the conventional 1D analysis deviates considerably for wide lifetime frequency distributions. Finally the range of applicability of this model is investigated by comparison with circuit simulations and full 2D modelling with DESSIS. The model is applicable if the length scale of structures in the diffusion length distribution or the spatial resolution of measurements is larger than the minimum of cell thickness and upper diffusion length bound