Solar cell improvement by using a multi busbar design as front electrode

Abstract

The demand for low-priced solar cells with higher efficiencies becomes more necessary to reach grid parity. An optimized solar cell design which uses the same equipment as state of the art solar cells could be easily implemented into solar industry. In this paper an approach for a front side design is discussed, using more busbars than the widely used three busbar design for the solar cell front electrode. A simulation program based on the two-diode model was used summing up the series resistances of each contributor in a module optimizing the number and geometry of wires needed. The simulations reveal that the advantages of the multi busbar design originate from a reduction of effective finger length, opening up new possibilities for the cell design. It is demonstrated that the multi busbar solar cell design can increase the module efficiency by 0.5%abs and a reduction in the consumption of silver of over 89% can be achieved by using seed and plate techniques. A significant surplus in short circuit current can be realized by using round wires.