High Efficiency Multi-busbar Solar Cells and Modules

In this paper, a detailed overview of multi-busbar solar cells and modules with selective emitter, a fine line screen printed front side metallization, and full aluminum rear side are presented. The designs of three-busbar and multi-busbar solar cells and modules are compared and assessed by solar cell, module performance, and Ag metal consumption. Assembled multi-busbar solar cells and four-cell modules are compared with industrial type three-busbar solar cells and modules that demonstrate average fill factor gains of 0.6% abs on the module level. A reduction in Ag paste consumption of about 50% abs for the front grid is achieved using the multi-busbar front electrode design with a fine line screen printing process. An advanced front side metallization technique using an Ag seed and Ag LIP approach demonstrates the potential to further reduce Ag consumption to values as low as 32 mg/cell.