Temperature-dependent performance of ultra-thin silicon heterojunction solar cells for space applications

Recently, ultra-thin silicon (Si) heterojunction (SHJ) solar cells with a base thickness of 40-60 μm and an efficiency above 20% have been successfully developed. These cells are a promising candidate to power small, light, and cost-effective satellites in the coming years. Therefore, insights into their performance under pertinent temperature and illumination operating conditions in space, i.e. a wide range of temperatures under the air mass zero (AM0) spectrum, are of significant interest. In this study, we investigate the temperature-dependent performance of ultra-thin SHJ solar cells under such conditions. Their temperature-dependent behaviour above 0 °C (under AM0) is then compared to that of thicker SHJ cells performing under the air mass 1.5 global (AM1.5G) spectrum. Below 0 °C, the cell electrical parameters remarkably decrease with temperature. This interesting behaviour of the open-circuit voltage and the fill factor might be attributed to the Schottky barrier height in this cell structure. Furthermore, we examine the temperature dependence of the specific power of the studied cells. At 25 °C, the obtained specific power is superior to those of most of the multi-junction cell structures, highlighting the advantage of using SHJ solar cells for space applications.