Crack Reduction in Tabbing and Stringing Processes for Solar Cells

Abstract:

Wafer cracking is considered to be an important loss in solar cell manufacturing as it crucially affects the production yield as well as the efficiency of solar cells fabricated. There is a certain chance of cracking in wafer when the substrate undergoes some thermal and/or mechanical loads during its fabrication. This research therefore aims to decrease the solar cells cracking in tabbing and stringing processes as the two processes are responsible for a great number of cracks in the substrate. A set of experiments was performed in this study, where soldering temperature and time were tested and the amount of cracks in solar cells was quantified. The findings showed that the use of 185°C soldering temperature with the soldering time of 1,200 ms can reduce the number of cracks in the tabbing and stringing of silicon solar cells. With this setup, the adhesion force between tabbing ribbons and substrate surface can also be promoted, thus preventing the delamination problem in the cell panels.

• Periodical: Key Engineering Materials (Volume 777)
• Pages: 126-131
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.777.126
• Online since: August 2018
• Authors: Atcharapha Kongwiriyaphaisan*, Viboon Saetang
• Keywords: Crack, Silicon, Solar Cells, Soldering, Tabbing

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