Series resistance modeling of complex metallization geometries of solar cells using conductive line decomposition

Abstract

All-back-contact (ABC), metal wrap through (MWT) and generally solar cell designs with complex metallization geometries are not amenable to simple series resistance (Rs) analysis based on small unit cells. In order to accurately determine the effects of Rs in these solar cells, SERIS developed a MATLAB program that captures the cell metallization geometry from rastered images, and breaks down the metalized areas into line segments of appropriate conductance. Its chief advantages over the conventional finite element method (FEM) solvers are: many-fold reduction in the number of mesh points used to define the metalized area and that the connections between elements are clearly defined, thus enabling approximations in the current flow pattern to speed up computation if desired. Its chief advantage over network/SPICE solvers is better adaptivity to complex metal geometries. The program solves for the terminal current-voltage characteristics, as well as the local current density, voltage and series resistance distributions, making it a versatile tool to aid the design of metal patterns. © 2012 IEEE.