Solar Cell Efficiency Improvement by New Metallization Techniques - the Day4 Electrode Concept

The standard module cell interconnection technique requires printed Ag front side busbars and rear side Ag/Al pads. From the standpoint of cell performance these contacts reduce cell efficiency strongly as a result of large cell shading and reduced surface passivations. Cells without busbars and pads would show a cell current and voltage increase and simplify the printing procedure. In this paper we introduce a new cell metallization technique which could be directly applied to standard industrial cells eliminating the need for rear pads and front busbars. Experiments were carried out to study the current and voltage gain of modified cells with the proviso that the cell fill factor will maintain at high level. Optimization experiments showed up to 0.8% higher cell efficiency for modified cells if compared to reference cells. Technique was furthermore successfully applied to 8 inch cells which showed fill factors of 77.9%