InGaP//GaAs//c-Si 3-junction solar cells employing spectrum-splitting system

In this work, we practically demonstrated spectrum‐splitting approach for advances in efficiency of photovoltaic cells. Firstly, a‐Si:H//c‐Si 2‐junction configuration was designed, which exhibited 24.4% efficiency with the spectrum splitting at 620 nm. Then, we improved the top cell property by employing InGaP cells instead of the a‐Si:H, resulting in an achievement of efficiency about 28.8%. In addition, we constructed 3‐junction spectrum‐splitting system with two optical splitters, and GaAs solar cells as middle cell. This InGaP//GaAs//c‐Si architecture was found to deliver 30.9% conversion efficiency. Our splitting system includes convex lenses for light concentration about 10 suns, which provided concentrated efficiency exceeding 33.0%. These results suggest that our demonstration of 3‐junction spectrum‐splitting approach can be a promising candidate for highly efficient photovoltaic technologies. Copyright © 2016 John Wiley & Sons, Ltd. We experimentally designed 4‐terminal a‐Si:H//c‐Si 2‐junction configuration that delivered 24.4% conversion efficiency with a spectrum splitter of 620 nm. Then, we boosted top cell performance by employing InGaP cells, resulting in an achievement of efficiency about 28.8%. InGaP//GaAs//c‐Si solar cells was demonstrated with a newly developed spectrum‐splitting system employing two optical splitters (645 nm, 875 nm). This new 3‐junction architecture offered an intrinsic efficiency of 30.9% under 1 sun, and more than 33.0% with 10× concentration.