A Measurement System for the Study of the Relaxation of the Light Soaking Effect in Perovskite Solar Cells.

The light soaking effect in perovskite solar cells improves their efficiency after a certain amount of time in the light and the relaxation of the effect in the dark causes their efficiency to drop again. The effect depends on the cells' chemistry and structure, irradiance, temperature, and their age. A lot of research has been focused on the light soaking effect itself, but much less on its relaxation, mainly because the cells are not electrically active in the dark, making it impossible to measure the same parameters as when they are illuminated. To overcome this limitation, a new measurement setup is presented which allows the perovskite solar cells to be light-soaked and relaxed in the dark under controlled conditions, including temperature, irradiance level, and electrical operating point (short circuit, open circuit or maximum power point). During the relaxation period in the dark, the measurement system periodically generates short pulses of light, during which the state of the perovskite solar cells is probed without excessively disturbing the relaxation process. The system can also perform other associated measurements, e.g. the cells' current and voltage, or perform I-V scans. [ABSTRACT FROM AUTHOR]