Rapid testing on the effect of cracks on solar cells output power performance and thermal operation

This work investigates the impact of cracks and fractural defects in solar cells and their cause for output power losses and the development of hotspots. First, an electroluminescence (EL) imaging setup was utilized to test ten solar cells samples with differing crack sizes, varying from 1 to 58%. Our results confirm that minor cracks have no considerable effect upon solar cell output, and they develop no hotspots. However, larger cracks can lead to drastic decreases in the output power, close to - 60%. Furthermore, as the crack area increased, there was a further increase in the cell's temperature under standard test conditions. On the contrary, no hotspots were found for the solar cells affected by significant creak areas (crack percentage > 46%) because there were insufficient areas to develop a hotspot. Last, a comparative analysis with solar cells affected by potential induced degradation (PID) was made. We found a strong relationship in the output power losses, and the PID test critically impacted the cells by developing localized hotspots at a temperature level close to 50 °C.