Investigation Of Quasi-omnidirectional Ultrathin Silicon Solar Cells

Ultrathin crystalline silicon(c-Si)solar cells provide advantages in reducing the use of c-Si material and being flexible,but there are several challenges need to be conquered,such as limited optical absorption,high sensitivity to surface recombination and complicated fabrication issues.Here,all-solution-processed Si nanopyramids(SiNPs)are proposed as the surface texture for ultrathin c-Si solar cells to solve the light absorption issue,whose preparation process is simple,low-cost and industrially compatible.Combining the SiNPs texture with good passivation technique of heterojunction solar cell structure,an efficiency of 15.1% with an open circuit voltage approaching 700 mV is realized on a 37-?m-thick c-Si solar cell.Moreover,both experimental and simulation investigation reveal that the SiNPs-textured ultrathin solar cells have quasi-omnidirectional light absorption characteristic,showing a potential to produce higher all-day output power compared with the Si micropyramids textured counterpart.To further reduce the cost of ultrathin c-Si solar cells,a direct copper metallization is also investigated in replacement of silver metallization,which can result in a comparable efficiency.The present work demonstrates the conventional industrial processes for achieving low-cost ultrathin c-Si solar cells.