Abstract
Abstract: Mini-module aging tests with differently interconnected heterojunction solar cells having industrially viable copper metallization are presented. The plating process comprises 3 steps: firstly, screen printing of a seed-grid layout using a copper-based paste, followed by deposition of a dielectric layer over the entire wafer surface, and finally, selective copper electrodeposition on grid positions. Modules with Smartwire interconnection, fabricated with M6 half-cells, are stable in extended TC and PID tests. DH degradation is at 5% after 2700 h (glass-glass modules without edge sealing). Shingle modules, realized in collaboration with CEA INES and AMAT, exhibit notably higher fill factor compared to reference modules with screen-printed silver paste. This improvement is attributed to the superior line conductivity achieved with plated copper. TC stability of shingle modules is very good, whereas after 2000 h damp-heat aging more than 2% loss in fill factor is observed. Using pattern-transfer-printing technology narrow, high aspect-ratio lines have been obtained: with a seed-grid of pure copper paste, reinforced with electrodeposited copper. Line dimensions and line resistance as well as first cell results are presented.
Funder
HORIZON EUROPE European Innovation Council
Horizon 2020 Framework Programme
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