Aging Characterization of Photovoltaic Backsheets in Extreme Climates Based on Multiscale Physical, Chemical, and Electrical Perspectives

Photovoltaic (PV) backsheets are an important component of PV systems that provide electrical insulation and mechanical support capability for PV modules. PV backsheets usually struggle to reach their designed lifetimes under extreme climates such as high temperature, strong ultraviolet (UV) radiation, sandstorms, and salt spray exposure. Therefore, investigating the aging mechanisms and reliable methods of aging characterization for PV backsheets under extreme climate is crucial for the long-term stable operation of PV systems. In this article, the effects of accelerated aging under multiple extreme environments on backsheet degradation were discussed. The methods for evaluating aging of backsheet life in terms of micro- and macroaspects were summarized. A planar scanning method for characterizing the migration rate of surface charge was proposed to fill the research gap in the field of aging characterization of the backsheet after salt spray corrosion. The method is easy to operate and can characterize salt spray corrosion aging of the backsheet. This provides a comprehensive summary and supplement of the aging phenomena of the PV backsheet in extreme climates as well as methods of aging characterization.