Evaluation of CIGS cell interconnection methods

To achieve desired voltage output, conventional solar panels have been fabricated using tab ribbons and soldering techniques to form the serial cell interconnection. This method is also adapted in CIGS and other thin film solar cells. Limitations of this interconnect technology has challenges relating to yield, reliability, and costs related to manufacturing processes and power loss due to grid shading along with cell packing density. Alternative cell interconnection methods have been under development. Several of these CIGS cell interconnection methods are evaluated including the use of silver loaded electrically conductive adhesive to attach the ribbon, shingle overlap and wire overlay type approaches. It is shown that the replacement of the traditional tab and string interconnect used by the silicon wafer module production by a higher packing density module design with low grid coverage can result in an increase in module performance by over 20%.