I–V curve characteristics of solar cells on composite substrate under mechanical loading

This research is aimed to conduct a characterization of I–V (current-voltage) curve changes in order to interpret the effects of physical defects such as microcracks of solar cells installed over structures to which mechanical load is applied on the power generation performance of solar cells, as well as to conduct fractography to interpret causes for reducing the power generation performance of the cells. To accomplish this, tensile specimens to which a mechanical load would be applied were produced using composite materials, which are representative light materials and solar cells that were attached to the specimens using the adhesive property of EVA film. In the experiment, mono-crystalline silicon solar cells were used, which are breakable and whose efficiency is approximately 24.2% (lab.). Also, in order to evaluate the power generation performance of solar cells under mechanical loading in real-time, a measuring device was designed to compare and evaluate the time point and property of fracture under mechanical loading. Moreover, fractography was conducted to analyze and consider causes for reducing the efficiency of solar cells. As a result of the experiment, it was found that the mechanical load applied to solar cells caused cracks to the surface and interior of the cells, which in turn reduced the I sc value and the V oc value of the I–V curve. The present study provides an initial set of valuation parameters in the maintenance and management of installed solar cells when applying solar cell technology to dynamic structures.