Mercury: Industrial IBC cell with front floating emitter for 20.9% and higher efficiency

Abstract

In this paper break-through results on our 6" industrial Mercury cells are presented. We gained more than 1% absolute in efficiency by optimizing the processes and design of the cells, resulting in 20.9% cell efficiency. We used standard industrial equipment and the number of process steps similar to our commercial n-Pasha technology. The screen-printed IBC cells can be interconnected by our proven industrial foil-based interconnection scheme. Together with this result, we present a method to characterize and quantify the pn-junction recombination contribution to V oc and pseudo-FF losses in the cell. Finally, our roadmap to 23% Mercury cells is presented.

Quantification of pn-Junction Recombination in Interdigitated Back-Contact Crystalline Silicon Solar Cells

“…ECN's IBC concept Mercury, based on a FFE, has so far reached conversion efficiencies up to 21.1%. [4], [5] Although the problems of electrical shading thus can be minimized, in this work it will be shown that another mechanism can induce a significant loss in performance for diffused-junction IBC solar cells. Specifically, it will be shown that a distinctive charge-carrier recombination current can be associated with the presence of the pn-junctions which border the at the rear surface of the solar cell.…”