Modules, in which pre-cut crystalline silicon solar cells-or shingles-are assembled into solar modules by placing the pre-cut cells in a shingle-like way on top of each other, have gained a lot of market attention in the last years. Such cell lay-up in the module has as main advantage an increased module output, due to more efficient packing without inactive space between cells. An additional benefit is that no important modifications to the cell production process are needed. The first commercial market-available modules use electrically conductive adhesives (ECAs) to connect the precut cells into strings. This paper will demonstrate that using ECAs with optimized properties will result in reliable solar modules. Adhesive properties such as adhesion strength, Young's modulus, volume resistivity and contact resistance are shown in combination with the thermocycle reliability data of ECA-assembled modules. Application techniques suitable for high-volume manufacturing are demonstrated. PURPOSE Most solar modules currently on the market are built up from ribbon-attached crystalline H-pattern cells in which the cells are side by side to each other and ribbons are interconnecting to these cells via soldering. The advantage of this approach is the low-cost interconnection and the robustness of the technology. However, there are some disadvantages to this module design such as high resistive losses and the incompatibility with very thin wafers. One of the new, promising advances for module assembly is a shingled cell technique whereby pre-cut crystalline cells are placed like roof tiles on top of each other (Fig. 1). Interconnection of the different pre-cut crystalline cells is achieved via electrically conductive adhesives (ECAs), which have an advantage over soldering in that they can absorb stresses due to CTE mismatches in the module. FIGURE 1. Assembly scheme of pre-cut cells with electrically conductive adhesives
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.