SEMI PV75 - Test Method on Cell Level for Potential-Induced Degradation Susceptibility of Solar Cells and Module Encapsulation Materials
This Standard was technically approved by the Photovoltaic – Materials Global Technical Committee. This edition was approved for publication by the global Audits and Reviews Subcommittee on August 31, 2016. Available at www.semiviews.org and www.semi.org in October 2016.
The purpose of this Test Method is the standardization of experimental setup and procedures for PID tests on solar cell level based on non-encapsulated silicon solar cells instead of complete modules.
This Test Method defines procedures to test and evaluate the PID susceptibility of wafer-based silicon solar cells and module construction components.
The only type of PID that is considered within this Test Method is the shunting of silicon solar cells due to high voltage stress induced leakage currents. This type of PID is called PID-s.
The Test Method is designed for silicon solar cells, having a front side emitter, a front side dielectric antireflective layer and front side contacts on top. For the sake of practicability and in order to minimize any border effects, solar cells tested with this Test Method must have edge lengths larger than 6 cm.
This Test Method is based on the fact that considered solar module designs comprise following layer stack (from top/sunny side to bottom): glass (or transparent polymer) cover sheet, polymeric encapsulation material and solar cells. The materials of the solar module back-side and their stacking order do not impact the measurement results.
Depending on which component is altered/exchanged for sampling, solar cells, polymeric encapsulation foils and glass sheets can be tested for their PID-s sensitivity. Following distinction is used in this Test Method:
- PID test of solar cells
- PID test of encapsulation polymer sheets
- PID test of module (glass) cover materials
With this Test Method, two or more different PID test specimens (hereafter: test specimens) can be compared quantitatively with respect to their PID-s sensitivity.
Referenced SEMI Standards