Impact of the Thicknesses of the p and p+ Regions on the Electrical Parameters of a Bifacial PV Cell

Abstract

The present paper is about a contribution to the bifacial PV cell performances improvement. The PV cell efficiency is weak compared to the strong energy demand. In this study, the base thickness impacts and the p+ zone size influence are evaluated on the rear face of the polycrystalline back surface field bifacial silicon PV cell. The photocurrent density and photovoltage behaviors versus thickness of these regions are studied. From a three-dimensional grain of the polycrystalline bifacial PV cell, the magneto-transport and continuity equations of excess minority carriers are solved to find the expression of the density of excess minority carriers and the related electrical parameters, such as the photocurrent density, the photovoltage and the electric power for simultaneous illumination on both sides. The photocurrent density, the photovoltage and electric power versus junction dynamic velocity decrease for different thicknesses of base and the p+ region increases for simultaneous illumination on both sides. It is found that the thickness of the p+ region at 0.1 μm and the base size at 100 μm allow reaching the best bifacial PV cell performances. Consequently, it is imperative to consider the reduction in the thickness of the bifacial PV cell for exhibition of better performance. This reduced the costs and increase production speed while increasing conversion efficiency.