Measurement and characterization of voltage- and current-induced degradation of thin-film photovoltaic modules

✍ Scribed by R.G. Ross Jr.; G.R. Mon; L.C. Wen; R.S. Sugimura

• Publisher: Elsevier Science
• Year: 1989
• Weight: 597 KB
• Volume: 27
• Category: Article
• ISSN: 0379-6787
• DOI: 10.1016/0379-6787(89)90037-9

✦ Synopsis

A number of important degradation mechanisms that determine the life of thin-film photovoltaic (PV) modules are driven by voltages and currents, either internal to the module, or between the module and its external mounting environment. Two important mechanisms are electromigration and electrochemical corrosion. Electromigration is current-induced diffusion of electrical conductors, such as the cell back metaUization, at high current densities approaching 10 6 A cm -2 of conductor cross-section. Electrochemical corrosion is the transport of ionic elements in the presence of applied electric fields, and in the case of PV modules is generally associated with corrosion of internal cell materials as a result of leakage currents from the cell string to the module exterior. This paper reviews the status of JPL's research into these mechanisms as they affect thin-film modules of amorphous silicon (a-Si) and CdTe.