Reduction of ECA Amount for the Ribbon Interconnection of Heterojunction Solar Cells

Electrically conductive adhesives (ECAs) offer a low temperature alternative for the ribbon inter - connection of temperature sensitive silicon heterojunction (SHJ) solar cells. The main drawbacks of ECAs are their high costs. To overcome this problem the used ECA amount is reduced by changing the application pattern. Four different patterns are investigated in terms of ECA reduction and long-term stability in TC200. Two different ECAs are analyzed in terms of DSC, TGA, electrical properties and rheology and 1-cell-strings with the four patterns for each ECA are produced for peel test analysis. One of the ECAs is used for the production of 3-cell-modules in glassbacksheet configuration with each of the application patterns to analyze module performance via I-V-measurements and EL imaging. In addition, the modules are aged via TC200. For lower ECA amounts a slightly higher degradation is observed but relative losses in FF are below 5 %.