Abstract
With the maturation of silicon-based technologies, silicon solar cells have achieved a high conversion efficiency that approaches the theoretical limit. Currently, great efforts are being made to enhance the reliability of silicon solar cells. When the silicon solar cells are made into modules, potential-induced-degradation (PID) occurs during operation because of the high voltage applied between the frame and the cells, which reduces the efficiency and output power. The diffusion of Na+ ions from the front glass and the increased leakage current along the migration path are the major causes of PID. In this work, atomic layer deposition (ALD)-grown amorphous thin Al2O3 layers are introduced underneath the front glass to prevent the diffusion of Na+ ions and the resulting PID. Accelerated PID tests showed that an ALD-grown Al2O3 layer of 30 nm could effectively suppress PID seriously affecting the conversion efficiency or light transmittance. The introduction of an ion-diffusion barrier underneath the front glass is expected to contribute to securing the long-term reliability of silicon-based electricity generation, together with the introduction of barrier layers inside the solar cells.
Highlights
The introduction of an ion-diffusion barrier underneath the front glass is expected to contribute to securing the long-term reliability of silicon-based electricity generation, together with the introduction of barrier layers inside the solar cells
According to the Best Research-Cell Efficiency chart reported by the National Renewable Energy Laboratory, the highest cell efficiency for a single-crystalline silicon solar cell is 26.1%, achieved by the Institute for Solar Energy Research, Germany [7]
This is referred to as potential-induced-degradation (PID), which deteriorates the photovoltaic performance of crystalline silicon solar cell modules over a long period of time [8–12]
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. 600–1000 V, the same high voltage is applied between the grounded module frame and the solar cell, which causes a large leakage current and loss of power output during the production of electricity This is referred to as potential-induced-degradation (PID), which deteriorates the photovoltaic performance of crystalline silicon solar cell modules over a long period of time [8–12]. The diffused Na+ ions accumulate at the interface between the anti-reflection coatings and the cells or at the stacking faults inside the silicon, which forms a conduction path, leading to a large leakage current [13–17], which gradually degrades the conversion efficiency and maximum power output of the modules. This layer can be located between the front glass and the front encapsulant or between the anti-reflection coating and the cell These blocking layers are known to effectively suppress the diffusion of Na+ ions inside the glass and the shunting path and reduce PID. As the thickness of Al2 O3 increased, the PID was remarkably reduced, and a 30 nm layer of Al2 O3 could suppress PID effectively
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
