Development of an LED-based External Quantum Efficiency measurement setup and validation tests on practical photovoltaic devices

Cell and module characterization represents a central aspect of photovoltaic research and development. In particular, the external quantum efficiency (EQE) provides detailed insight into the spectral response of a photovoltaic device, enabling the derivation of key performance-related parameters and the identification of optical and electrical losses. This thesis builds upon an existing experimental setup based on an LED solar simulator to enable EQE measurements on mini-modules fabricated at the prototyping laboratory of the Eurac Institute for Renewable Energy.

The primary objective was to develop a fully automated measurement procedure. To this end, a Python-based control routine was implemented, allowing the sequential activation of individual LEDs of the simulator, automated current acquisition, and subsequent data processing and visualization. A comprehensive data acquisition framework was established, enabling reproducible and automated measurements.

Furthermore, several improvements were introduced to enhance data quality, including refined current measurement procedures and an optimized calibration approach. The performance of the system was evaluated on photovoltaic cells and mini-modules with varying optical properties. The developed setup demonstrated good suitability for comparative analyses of modules exhibiting different optical behaviors. Although certain limitations remain, the system proved capable of reliably capturing spectral trends and key characteristics, including ultraviolet cut-off behavior and losses associated with coloring techniques, thereby providing a practical and pivotal tool for mini-module characterization.