Thermal stress reduction

Thermal stress reduction means limiting the thermal and thermomechanical stressors that make cell interconnection failure progress, and it is paired with replacing modules whose interconnect failures are electrically active. Repeated temperature swings fatigue the cell interconnect ribbons, which is a known degradation mechanism for interconnects. Hotspots caused by partial shading can add thermomechanical stress and speed up fatigue of the cell interconnections, so they are one stressor worth addressing. Cells or strings that shift during lamination add stress to the interconnections, raising the chance of interconnection failure under cyclic thermal stress. Laminated modules also hold residual thermal stress because their components expand and contract at different rates with temperature. Thermal-cycling failures are still seen in the field in hot climates, and the sources describe this action only as general guidance without listing specific measures or how effective they are.

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• sentence 2: support check: partial - The passage lists 'fatigue of ribbon due to thermal cycling' as a failure mode, but it doesn't say 'repeated temperature swings' in those words and says nothing about interconnects generally.
• sentence 6: support check: partial - The passage says this failure type is still observed in hot climates, but it doesn't say the sources give only general guidance without specific measures or effectiveness data. -->