Electrical Characterization

LID measured with flasher
© Fraunhofer CSP
The comparison of diffusion lengths of local charge carriers before and after light-induced degradation permits the classification of the particularly susceptible parts of a solar cell.

High efficiency and a long service life are two of the central demands placed on innovative photovoltaics products. Individual module components as well as complete modules must satisfy the highest standards. To obtain a quantitative evaluation, the Fraunhofer CSP applies innovative laboratory measurement methods applicable to solar cells and modules in combination with statistical data evaluation, model building and numeric simulation. In addition, a macroscopic assessment by means of spatially and spectrally resolved measurements is an essential element in our multiscale approach to identify the causes of defects, in which both macroscopic and microscopic fault patterns are associated with production-related performance parameters.


  • Power evaluation and loss analysis of solar cells and modules
  • Spatially resolved and spectral measurement methods for defect localization
  • Development of new measurement methods and instruments for photovoltaics


LID test
© Fraunhofer CSP
The LID test reveals how degradation mechanisms impair the performance of solar cells and module components.

Spatially Resolved Loss Analysis of Cells and Mini Modules

A detailed loss analysis of solar cells and modules is of importance for quality control and process optimization purposes. Losses in the material, at the passivated layers or contact points, can be localized separately with a precision of several micrometers by applying methods of imaging and spectral resolution. This information can then be connected with the performance parameters, allowing for a rapid root-cause analysis and a significant acceleration of development processes.

LID test
© Fraunhofer CSP
The LID test shows how degradation mechanisms affect the performance of solar cells and module components.

Cell Degradation

The quality of a solar cell is not only determined by its output capacity after manufacturing, but also by its long-term stability. When exposed to light, degradation mechanisms are capable of decreasing the performance of solar cells and module components. Quantification of the long-term stability under operational conditions is therefore indispensable for product qualification. The identification of the degradation mechanisms and the development of new methods for their avoidance might represent a significant cost advantage in the development of new technologies and products.

Article in PV International magazine

Press Release: LID-Test for PERC Cells

Electrical characterization single-cell mini module
© Fraunhofer CSP
Electrical characterization of a single-cell mini module.

Rapid Component Testing of PV Modules

Both capacity and reliability of a PV module are based on the well-tuned interaction of the single module components. We are able to quantify the influence of these single components on module performance by applying adapted test procedures and test carriers, and thus contribute to accelerating the development of new PV products and lowering the development costs.

© Fraunhofer CSP
Uniformitätstester für Lichtfelder.

Development of Measuring Systems and Prototypes for Innovative Measurement Methods

New measurement and test setups have to be continuously developed alongside the development of new PV technologies. This shortens the time needed for development and optimizes the control of quality in the manufacturing processes.