4. 1 PV Module Design, Manufacture, Performance and Reliability
Summary / Abstract:
Electrically conductive adhesives (ECAs) can replace soldering for the interconnection of cells within photovoltaic modules such as those based on IBC-based technology or the shingling interconnection approach. They can also be used for applications in which soldering is no longer appropriate or lacks long-term reliability, such as temperature-sensitive SHJ-based technology or vehicle-integrated photovoltaics. The aim of this work is to show further improvements in the development of a method to characterize the contact resistivity of joints based on these adhesives. The developed method, which is based in the Transmission Line Method, is shortly explained while the treatment of the raw data and the obtained results are clarified in detail. Samples were manufactured using nine different commercially available adhesives that contained different polymer matrices (acryl and epoxy) and conductive filler (silver and copper with silver coating). It is concluded that the introduction of the adhesive significantly increases the complexity of the system under study and increases the number of calculations required to remove non-important resistive components so that the contact resistivity of the joint can be extrapolated. It is also shown that although measurements per sample are statistically significant, a larger number of probes should be manufactured so as to extrapolate a non-misleading value. This means that many measurements per sample with several samples per ECA composition are required.