Woven multi-ribbon interconnection for back-contact cells: Extending the functionality of the encapsulant

Abstract

Back-contact solar cells have shown their potential in the past, with record efficiencies approaching the theoretical maximum value. In parallel, industry-relevant fabrication methods of efficient cells are being developed. Next to this increased power yield, the absence of frontside metallization on the cells greatly improves their aesthetics. The main challenge to manufacture modules using back-contact cells is finding a cost-effective method to electrically interconnect them. In this work, we introduce a novel way of doing so. The interconnection concept is based on a fabric with interwoven metal interconnection ribbons and polymer encapsulant ribbons. It has the advantage of optimized material consumption, low manufacturing cost and low manufacturing temperatures, which lowers the induced thermo-mechanical stress. First proof-of-concept single cell modules have been fabricated and have shown to pass 200 thermal cycles (-40 degrees C to 85 degrees C) with no decrease in performance. These reliability tests prove the potential of the concept.