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Cell dark current–voltage from non-calibrated module electroluminescence image analysis

Colvin, Dylan J.·Schneller, Eric J.·Davis, Kristopher O.
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Abstract

Here, we present a fast, accurate, and reliable method of obtaining cell dark current–voltage (I–V) curves from module electroluminescence (EL) images without requiring calibration or correction. For a pristine module, EL-derived dark I–V are compared to directly probed data for a variety of changing imaging parameters: camera sensor, lens, filter, aperture width, exposure time (level of sensor saturation), number of images used, and various combinations of these. Pristine modules and those experiencing different modes and degrees of degradation are examined. A recent study of modules using five different cell technologies demonstrates the practicality of our “EL sweep” technique for performance and degradation studies.

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14 SOLAR ENERGYCharacterizationDark I–VElectroluminescence imagingImage analysisMetrologyNon-calibratedReliability

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Colvin, Dylan J., Schneller, Eric J., Davis, Kristopher O.. 2022-09-06. Cell dark current–voltage from non-calibrated module electroluminescence image analysis. https://doi.org/10.1016/j.solener.2022.08.043

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