Advanced loss analysis method for silicon wafer solar cells

Abstract

An advanced loss analysis method for silicon (Si) wafer solar cells is introduced. The capabilities of the method are exemplified for an 18.1% efficient p-type Czochralski-grown monocrystalline Si wafer solar cell. The method is based on a set of high-precision measurements, including light and dark current-voltage, hemispherical reflectance, quantum efficiency, and photo- and electroluminescence intensity images. The analysis provides a detailed quantification (in W/cm2) of the seven main power loss mechanisms in a silicon wafer solar cell: Front metal shading, front surface reflectance in the active cell area, front surface escape of light, series resistance, shunt resistance, non-perfect active-area internal quantum efficiency, and the forward-bias current at the one-sun maximum power point. The presented loss analysis method is entirely based on measured parameters and does not involve any curve fitting or computer modelling of the solar cell. The only assumptions behind the quantification of the various loss mechanisms are that the cell can be described with a one-diode equivalent circuit model and that it obeys the superposition principle. © 2011 Published by Elsevier Ltd.