Low Intensity Low Temperature / dark measurement campaign for the JUICE Photovoltaic Assembly - from solar cell to full-scale qualification model

The JUICE (JUpiter ICy moon Explorer) mission is characterized by a severe environmental condition, as the spacecraft will mainly operate in the Jovian region of the solar system. Low intensity, low temperatures and high radiation doses are the challenging factors for the solar array and especially for the photovoltaic assembly. Following a technology research program [1], the $3\mathrm{G}28$ bare solar cell by Azur Space has been selected; moreover, dedicated acceptance criteria were defined to screen the devices for highest and predictable performance under the harsh Jovian condition. Leonardo has then started a pre-qualification at solar cell and protection diode assembly level (cell and diode with coverglass and interconnectors). This pre-qualification identified the technology to be finally tested in accordance to the relevant ECSS standard, specifically including also a test in low intensity low temperature (LILT) condition also for the full-scale photovoltaic assembly qualification model.