17.2% efficiency CuIn1−xGaxSe2 thin-film based mini-module thanks to alternative architecture yielding 81% fill factor

An alternative to conventional Cu(In,Ga)Se2 module structure is proposed and experimentally investigated. This alternative module structure, which consists in applying metallic buses to connect monolithically adjacent cells in series, is likely to offer the opportunity of minimizing both optical and electrical losses observed in conventional module structure compared to small area cells. The fabrication process of such alternative modules is presented. The performances achieved are discussed in comparison with a standard small-area-cell elaborated simultaneously. Despite slightly lower output voltage per cell, the alternative module structure demonstrates an efficiency of 17.2% (with 81% fill factor), against 16.4% (with 75% fill factor) for the standard cell. This promising result opens new routes to decrease the gap observed between small-area-cells and industrial modules.