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The existence of cracks in silicon solar cells can drastically reduce the electrical performance of an individual cell and even of an entire photovoltaic module. An in-depth understanding of the influence of cracks on solar cells enables therefore calculations of the crack impact and other following effects on module level. This paper shows a detailed analysis of the electrical influence of cracks with two different spatially resolved methods including global and local current-voltage characteristics. The main influence of cracks is an increased recombination current density in the depletion region, which is clearly shown by spatially resolved dark lock-in thermography measurements with local current-voltage investigation. This increased recombination current density affects further cell parameters such as the efficiency, which is confirmed also by the global current-voltage characteristics. The additionally used ratio image technique based on electroluminescence measurements is in comparison with the local current-voltage method, the more reliable and faster method for the crack detection itself, and allows on cell-level and module-level a continuous inspection of cracks.

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