Monitoring of Si-solar cell degradation with electroluminescence

• A monitoring method for solar cell degradation under operation conditions proposed.
• The method is fully applicable to the cells with complicated structure (e.g. PERC, etc.).
• Degradation related changes in VOC can be estimated from electroluminescence intensity.
• Degradation kinetics is accessible from the time-dependence of EL-intensity changes.
• The method indicates on faster and more severe degradation in PERC cells.

Monitoring of the intensity of band-to-band electroluminescence (EL) from B-doped Cz-Si solar cells allowed reliable detection of their degradation under forward bias. Degradation related changes in the open circuit voltage for a cell can be well estimated from the related changes in the EL-intensity value under fixed forward current flow. Kinetics of the degradation could be accessed from the time-dependence of EL-intensity changes. The method of monitoring of the degradation process is fully applicable to the cells with complicated structure, e.g. cells with passivated emitter rear contact (PERC). Comparison of degradation process in standard and PERC solar cells indicated on faster and more severe degradation in PERC cells.