Optimize silicon solar cell micro-structure for lowering PV module power loss by thermal cycling induced

Photovoltaic module reliability is an important research subject. Solar modules have to suffer accelerated aging test in order to quickly certify the module quality. In general, solar modules must be able to undergo field exposure over 20 years and their power loss could not be over 10%. Thermal cycling test is a critical index for solar modules. After thermal cycling test, some micro cracks easily appeared in the solar module using thicker copper ribbon as the internal connective wire. The mismatch of the layer´s coefficients of thermal expansion is a primary source of solar module failure. This study focuses on the metal layer´s microstructure variation. Through changing the metal layer´s microstructure to reduce solar modules power loss induced by thermal cycling.