LONG-TERM RELIABILITY OF AMORPHOUS-SILICON SOLAR-CELLS

The long-term reliability of amorphous silicon solar cells of 1988 pro ducts over more than ten years is estimated by a simulation method usi ng the Weibull function with the experimental data of 1988 products ex posed outdoors for five years and those of 1983 products exposed outdo ors for ten years. The mathematical model is developed based on the ac celerated tests and recovery tests in a laboratory for a short period of time. The simulation method is discussed. The decrease of the conve rsion efficiency of 1988 products after ten years of exposure is estim ated to be 25% and 35% at best and worst, respectively. The newest pro ducts having initial conversion efficiency of over 13% in a small cell are expected to maintain an efficiency of about 10% at best over a de cade.