Theoretical Study of Morphologically Modified EVA Film to Minimize Metal Grid Reflection Loss

Abstract

Solar cell modules mainly consist of EVA film and a metal grid. The EVA film is used as waterproof and UV-resistant, which makes it an ideal adhesive film for solar modules installed outdoors. As well, standard crystalline solar cells are generally fabricated with the front grid pattern of silver paste contact. Metal grid cannot help accompanying with shading losses caused by the presence of metal on the top surface of the solar cell, which prevent light from entering the solar cell. The shading losses are determined by the transparency of the top surface, which, for a planar top surface, is defined as the fraction of the top surface covered by metal. In order to fabricate highly efficient solar cell devices, the shading losses should be minimized. In this article, a theoretical estimation has been made to construct a morphologically modified configuration of EVA film so as to minimize the shading losses. According to our numerical calculations and optical simulations, by adopting only slightly modifying the EVA film, the transparency of solar cell modules can be significantly increased by as much as 4%.