High radiant flux photovoltaic cells for solar proximity missions
Solar cells are widely used in all near-Earth space missions, with solar panels increasingly getting bigger to supply the growing power requirements of sophisticated spacecrafts. Most solar cells begin to lose their efficiency significantly when their bulk temperature rises above about 60 °C. This work describes gallium arsenide solar cells coated with infrared-reflecting pigments, contained in a silica film. Measurements indicate that such coated cells retain more of their efficiency at higher temperatures than similar uncoated cells with the former producing around 7.6% more power than the latter. The structure, fabrication and photovoltaic characteristics of pigment-coated single-junction gallium arsenide solar cells are described. The basic idea could be extended to triple-junction cells which are widely used for space missions.